What was the impact of the invention of the sewing machine?

The major impacts of the invention of the sewing machine were to 1) create the clothing industry and 2) to help allow people to have more clothing.

Before the invention of the sewing machine, all sewing had to be done by hand.  Cloth could be made by machines, but the actual sewing of garments and other things could only be done by hand.  People would either make clothes at home by hand or would buy them from tailors.  This made clothing very expensive (if you bought it) or time-consuming (if you made it yourself).  The invention of the sewing machine changed this.

Once Elias Howe invented the sewing machine, clothes could be made on a much more industrial scale, much as cloth was.  People could set up factories with large numbers of sewing machines.  Workers using sewing machines could produce garments much more quickly than was previously possible.  When workers can make things more quickly, that also means that the products can be sold more cheaply because the workers do not have to be paid as much.  When clothes become cheaper, people are able to buy more clothing.  In addition, the invention of the sewing machine even helped people who sewed at home.  Sewing clothing at home with a machine was much quicker than hand-sewing and so a woman (almost always a woman) could make more clothes for herself and her family.

In these ways, the invention of the sewing machine had important impacts.  It helped to build the clothing industry and it improved people’s quality of life by allowing them to own more clothes.

How would I calculate the relative mass of an element?

All the atoms of an element may or may not have the same atomic mass. The atoms that have the same atomic number but different atomic mass are known as the isotopes. All the isotopes of an element may not have the same abundance. Once we know the relative abundance of each isotope of an element, we can calculate its relative mass.

The relative mass or relative atomic mass of an element is the average mass of its isotopes weighted according to their relative abundance. So, if we have an element with 3 isotopes that have atomic masses m1, m2 and m3 and relative abundance levels of a1 %, a2 % and a3 % (remember, a1 + a2 + a3 = 100%); its relative mass can be calculated as:

M = (m1a1 + m2a2 + m3a3)/(a1 + a2 + a3)

Oxygen has 3 isotopes, O-16, O-17 and O-18, with relative abundance levels of 99.762%, 0.038% and 0.200%. Thus, its relative mass is

= (99.762 x 16 + 0.038 x 17 + 0.200 x 18) / (100) = 16.008.

(Note that actual relative mass may be slightly less than these calculations, due to conversion of a small amount of mass into nuclear binding energy.)

Hope this helps.

Correct the following sentences and explain where the sentences are grammatically incorrect:1. The downslide country of the economy is a on2....

1. The downslide country of the economy is a on

In this sentence, the words are simply in the wrong order. If our job was to rearrange the exact words from the original sentence into a clear sentence, we could write it this way:

"The economy of the country is on a downslide."

2. If i had known, i will not have told him 

This should say:

"If I had known, I would not have told him."

(Use a contraction if you prefer: "If I had known, I wouldn't have told him.")

The error is in the verb "will not have," which is incorrectly written in a future tense in the original sentence. We'll correct it to "would not have," a past tense, so that the whole sentence refers to the past.

The concept here is sometimes called "verb tense consistency." Rather than jumping around randomly in verb tenses, you should try to stick to one verb tense.

3. The price of cars have escalated

This should say:

"The price of cars has escalated."

The error is that the verb, "have," doesn't agree with the subject, "price." "Price" is singular, so it needs a singular verb. You would say, for example, "The price is too high" or "The price changes all the time." (But you wouldn't say "The price are too high" or "The price change all the time.")

"Wait!" you might say. "But the word 'cars' is right next to the verb. So shouldn't I say 'cars have escalated'?"

Actually, no. The difficult task with sentences like this is to recognize that subjects aren't always written right next to their verbs, and in this case, "cars" is not the subject of the verb "have escalated."

Ask yourself, what escalated? Not the cars! The price escalated. So, match the verb to the real subject, "price."

One way to help avoid mistakes in subject-verb agreement is to ignore or cross out any prepositional phrases that get in the way of the subject and verb. Here, in the original sentence, you could cross out "of cars." That would help you see the sentence should really be saying "The price...has escalated."

What is the most important thing to Margot from "All Summer in a Day"?

Sun is the most important thing to Margot.

For Margot, there is nothing more important than the sun.  She is from Earth, so she remembers the sun.  Not only does she remember it, but she cares more about the sun than anything else.

The other kids in Margot’s class have never really seen the sun in their lifetime.  It last came out seven years before.  Margot, on the other hand, remembers the sun.  That memory dominates her existence, and makes her different from the other kids.  They are jealous of the fact that she came from Earth, but coming from Earth makes the constant rain even harder on her.

There was talk that her father and mother were taking her back to Earth next year; it seemed vital to her that they do so, though it would mean the loss of thousands of dollars to her family.

Margot keeps herself apart from the other kids.  She doesn’t really understand the other kids, and they do not really understand her.  She is obsessed with the sun.  It is all that matters to them.

When the class sang songs about happiness and life and games her lips barely moved. Only when they sang about the sun and the summer did her lips move as she watched the drenched windows.

She does not ever get involved in the games the other kids are playing.  She won’t play with them and she barely talks to them.  When she does interact with the other kids, they are rude to her and bully her.

Unfortunately, the other kids in the class do act very cruelly to Margot.  They lock her in a closet so that she misses the sun.  This is something that will utterly destroy her, because she needed the sun even more than the other kids.

What does Hannah Arendt say about freedom?

Though not grounded in a careful reading of any particular text or set of texts, Arendt convincingly argues in "What Is Freedom?" that political liberty has become—in modern philosophical and theological discourse—“a potential freedom from politics” (149) defined in terms of a “guaranty of security” (ibid.). Though not specifically channeling Hobbes, Arendt points to the Hobbesian security state as the example par excellence of this negative freedom: “security, in turn, made freedom possible, and the word ‘freedom’ designated a quintessence of activities which occurred outside the political realm” (ibid.). Freedom, here, appears not so much the goal of politics or its founding principle, but rather as a kind of byproduct of the security state. Political subjects are only minimally free to preserve their own lives in the realm of biological necessity; as Arendt puts it, “the total domain of the political, was now considered to be the appointed protector not so much of freedom as of the life process” (150), the biopolitical aspirations of the security state effectively quashing freedom through the political.

Against what she terms the modern age’s insistence on the “separ[ation] [of] freedom and politics” (ibid.), Arendt wishes to found a conception of freedom that is thoroughly imbricated within the political itself. Put briefly at the end of the essay’s first section, Arendt states “that the raison d’etre of politics is freedom and that this freedom is primarily experienced in action” (151). This freedom—against the negative freedom of the security state—is a positive one, grounded in the political subject’s right to act in the public (political) realm beyond the mere necessities of biological life, a freedom to politics rather than a freedom from it. In fact, she goes so far as to claim: “Freedom as a demonstrable fact and politics coincide and are related to each other like two sides of the same matter” (149), effectively conflating freedom-in-action and the political as such. 

Arendt is able to argue that freedom constitutes the essence of politics rather than its marginalized byproduct by emphasizing the importance of action, community, and (implicitly) natality to her conception of freedom. Action, here, by being free from both the intellect and the will (152), becomes the means through which humans actualize what (through Montesquieu) she calls principles (e.g. “honor or glory, love of equality … but also fear or distrust or hatred” (ibid.), which, due to their abstract character, can enter the political only through action. As she puts it: “Men are free—as distinguished from their possessing the gift for freedom—as long as they act, neither before nor after; for the be free and to act are the same” (153). Moreover, this actualization of principles through action depends entirely on a common, public space in which multiple political subjects act simultaneously, what Arendt calls at one point “a kind of theater where freedom could appear” (154). Extending the metaphor further, she likens the political actor to a performance artist who “depend[s] upon others for the performance itself” (ibid.). What Arendt finds so valuable about this positive freedom to politics—in contradistinction to the negative freedom lying at the heart of the security state—is its capacity “to call something into being which did not exist before” (151) or, to use the term we have been teasing out of The Human Condition, its ability to bring about the event of natality. Freedom—characterized by action, community, and natality—becomes in Arendt’s hands the very stuff of politics, an intersubjective acting together in the public realm to initiate the new and open up the possibility of new futures for the polis.

Despite the seemingly wholly secular character of Arendt’s new definition of freedom which constitutes the first two parts of the essay, grounded in Kant, everyday experience, and scientific views of causality, Arent devotes the second half of the essay almost exclusively to issues of political theology. On the one hand, she levels a critique against a certain strain of Pauline and Augustinian theology. On the other, however, she subsequently reads into them at the very least a kernel of her freedom to politics.

Beginning in Section III, Arendt takes up the issue of “the Christian and modern notion of free will” (157) to analyze (what she sees as) its negative effects on ideas of political freedom. The importance of this Christian tradition for Arendt almost cannot be understated. As she writes: “For the history of the problem of freedom, Christian tradition has indeed become the decisive factor” (157). Locating in Christian theology a fundamental split between what she calls the “I can” and the “I will,” a split unknown and incomprehensible to the ancient philosophers, Arendt contends that freedom becomes interiorized, thought in terms of the individual subject rather than the collective of the polis. As a result, “will, will-power, and will-to-power are for us almost identical notions; the seat of power is to us the faculty of the will as known and experienced by man in his intercourse with himself” (160). This resignation of freedom to the realm of the individual subject and his will, Arendt argues, has “fatal consequences for political theory” (162). More specifically, freedom “became sovereignty, the ideal of a free will, independent from others and eventually prevailing against them” (163). The interiorized freedom of Christian theology thus becomes the grossest suppression of freedom in the forms of, for example, the Hobbesian state and the rise of totalitarianism. Succinctly put: “If men wish to be free, it is precisely sovereignty they must renounce” (165).

While this rejection of both the notion of sovereignty and the individual subject of Christian theology might appear to be an outright rejection of political theology on Arendt’s part, she also finds in the very same tradition an underground current (to channel Althusser) of “a freedom which is not an attribute of the will but an accessory of doing and acting” (165). She finds in Augustine’s only political writing, The City of God, “an entirely differently conceived notion” (167) of freedom than that which he champions in his strictly theological writings. In City of God, Arendt argues, freedom is both “a character of human existence in the world” and the “faculty of beginning” reaffirmed in “the birth of each man” (ibid.), a definition approximating Arendt’s own by emphasizing both being-in-the-world and natality. She goes on to locate a similar tendency in the New Testament which, to her reading, exhibits “an extraordinary understanding of freedom” (168). This extraordinary freedom manifests itself in the decidedly theological concept of the miracle which serves as an “interruption of some natural series of events, of some automatic process, in whose context they constitute the wholly unexpected” (ibid.). The miracle, then, becomes yet another example of natality and, when secularized at the hands of Arendt, an example of political freedom itself.

What are developmental methodologies?

Introduction

Developmental methodologies have as their purpose the
investigation of questions about age-related changes throughout the life span, and they
include both a variety of research methods and the designs within which these methods
are applied. The overarching framework for developmental methodologies is the
scientific
process. This process embodies systematic rules for testing hypotheses
or ideas about human development under conditions in which the hypotheses may be
supported or refuted. This process also requires that research be done in such a way
that it can be observed, evaluated, and replicated by others.

Data collected through developmental methodologies can be characterized as descriptive, correlational, or experimental. Descriptive data simply describe a variable—for example, the average age of the adolescent growth spurt. Correlational data provide information on relationships between variables, such as the association between newborn size and the amount of smoking a mother did during pregnancy. Experimental data result from the careful manipulation of one variable to discover its effect on another, and only in experimental studies can cause-and-effect relationships among variables be inferred. For example, experimental studies demonstrate that training techniques can cause an improvement in the memory performance of persons in late adulthood.

Research Categories

Developmental research methods are commonly separated into three general
categories. One of these categories is observational methods, in which researchers observe
people as they go about their lives. The settings for such research can be homes,
schools, playgrounds, nursing homes, and so on. Observational research may be quite
subjective, as in diary studies in which the researcher writes down observations and
impressions in a free-flowing manner. The extensive cognitive developmental model of Jean
Piaget had its beginnings in hypotheses that emerged from diary
studies of his children. On the other hand, observational research may be very rigorous
and systematic; researchers carefully define what and how they will observe and record
and then train data collectors before any formal observations are made. Videotaping of
children’s language samples, which are then carefully segmented and analyzed, is an
example of this systematic approach.

The second category, self-report methods, is generally more intrusive than observational research. It involves
asking questions of participants and may take the form of interviews, questionnaires, or
standardized tests. Interviews may be free-flowing or highly structured, with
predetermined questions and sequence. The famous studies of sexual behavior by
Alfred
Kinsey, for example, used carefully planned interview techniques.
Questionnaires and standardized tests are usually structured with both questions and
response categories provided. Questionnaires are often used to gather descriptive
information such as size of family or educational level, as well as opinions on a
variety of social issues. Standardized tests are used to assess a great variety of
information, including measured intelligence, vocational interests, and self-concept.

The third category of developmental methods involves experimentation. Experimentation can occur in natural settings where individuals may not be aware that they are participating in research, such as in situational studies of children’s moral behavior. It can also occur in laboratories where individuals may be unaware of their participation or fully aware of the artificiality of the setting and even the study’s intent. Research using a complex apparatus to study newborn perception is one example of the former, while research using nonsense syllables in memory tasks to assess age differences in free recall is an example of the latter.

Research Methods and Designs

Research methods can be compared according to their generalizability and their ability to control participants’ selection, experiences, and responses. Generalizability refers to the extent to which research results are applicable to people beyond those who participated in the study. Generally, methods that are more intrusive and contrived provide the greatest opportunity for control—the extent to which a researcher can regulate who participates in a study, what the participants experience, and how the participants respond. Thus, laboratory experimentation often is associated with high levels of control. For the same reasons, however, questions are raised regarding the applicability to the real world of data collected in the artificiality of a laboratory. Thus, observation in natural settings is often associated with high levels of generalizability. Both control and generalizability are desirable and are sought in developmental research regardless of method.

To assess whether age-related changes exist, developmental research methods are
applied within larger frameworks of research designs that require that data be collected
at two or more points in developmental time. These designs permit inquiry into whether
behavior is the result of maturational changes associated with age changes, such as the
emergence of language in infancy; the effect of the immediate social context, such as a
nation at war; or the effect of historical events which affected everyone born at about
the same time (a group known as a cohort, a term which means an identifiable group of
people that has a common association), such as growing up during the Great Depression.
Two of the most common designs are cross-sectional and longitudinal designs. In cross-sectional
designs, data are collected on
different cohorts at the same time. These designs permit an examination of age
differences in behavior; however, they cannot separate out the effects of different life
experiences between cohorts. In longitudinal designs, data are collected on the same cohort a number
of times. These designs permit an examination of developmental trends for individuals;
however, they cannot separate out the effects of social change, since no comparison can
be made to a group not experiencing the social context. An alternative to
cross-sectional and longitudinal designs is sequential designs, in which data are collected
on a number of cohorts a number of times. These designs are able to reveal the effects
of age, cohort, and social context. Because of the difficulties of administering these
complex designs and their expense, sequential designs are least often applied, even
though they provide the most useful developmental information.

Regardless of the research methods or designs utilized, developmental methodologies must account for the complexity of human development. They must control for multiple variables, such as age, cohort, social context, socioeconomic class, gender, educational level, and family structure. They must take into account the culture of the participants, and they must protect against bias in formulating the research hypothesis, applying the methods, and interpreting the data collected.

Developmental methodologies are applicable to literally any developmental question, from conception to death. Resultant data permit description of current status, comparison between groups, prediction of developmental patterns, and explanation of the causes of developmental outcomes. Description, comparison, prediction, and explanation all contribute to a better understanding of development, which in turn permits the fostering of social settings that promote healthy development, as well as intervention to prevent potential developmental problems or to counter developmental problems already in existence.

Newborn Research

Research on the competencies of newborns provides one demonstration of the relationship between understanding and therapeutic intervention. Observational research of newborns and young infants indicates a cyclical relationship in infant attention when the infant is interfacing with a caregiver. This cycle is one of activation, discharge, and then recovery when the infant withdraws its attention. Caregivers who adjust their behavior to their infants’ rhythms by entering into interaction when their infants are responsive and slackening off when their infants withdraw attention experience a greater amount of time in which the infant looks at them than do caregivers who either attempt to force their own rhythms on their infants or continuously bombard their infants with stimulation.

Psychologists are applying this understanding as part of an overall intervention program with premature infants who enter the world at risk for physical, social, and intellectual impairments. Premature newborns require greater stimulation than full-term newborns before they respond; however, they also are overwhelmed by a level of stimulation to which full-term newborns respond very positively. This narrow range of tolerance can disrupt the relationship between a parent and the premature infant. In experimental research, parents of premature newborns have been trained to imitate everything their infants do, and by so doing follow their infants’ rhythms. This training helps parents remain within the narrow tolerance of their infants and increases the amount of positive interaction both experience. This, in turn, contributes positively to healthy social development of this high-risk group of infants.

Television Studies

Research on the developmental effects of television provides a
demonstration of the relationship between understanding and influences on social policy.
Beginning in the mid-1950s with a series of inquiries and hearings sponsored by a Senate
subcommittee on juvenile delinquency, followed by a Surgeon General’s report and
associated Senate hearings in the early 1970s and a major National Institute of Mental
Health report in the early 1980s, questions about the effect of violent programming on
children have been raised in the public domain. Consequently, public efforts have
emerged to control the amount and timing of violence on television and to regulate the
number and content of television commercials targeted at children. Central to the
national debate and social policies surrounding television content has been the
application of developmental methodologies.

Significant research in this area emerged in the early 1960s with the
now-classic
Bobo doll studies of Stanford University psychologist Albert Bandura. In a
series of experimental laboratory studies, nursery school children observed a variety of
televised models behaving aggressively against an inflatable punching-bag clown. Later,
when their play behavior was observed in a controlled setting, children clearly
demonstrated imitation of specific aggressive behaviors they had viewed. Additional
experimental laboratory studies have been conducted; however, they have been
consistently criticized for their artificiality. Consequently, field experiments have
emerged in which the experimental variables have been actual television programs, and
the effects have been assessed on spontaneous behavior in natural settings, such as
playgrounds.

Since experimental studies require systematic manipulating of variables for their effects to be observed, and since the manipulations of levels and types of aggression and other relevant variables such as home violence are either unethical or impractical, numerous correlational studies have also been conducted. Most of these have assessed the relationship between the amount of violence viewed and subsequent violent behavior, violent attitudes, or perceptions of violence in the real world. Many of these studies have applied longitudinal or sequential designs covering many years, including one longitudinal study that covered a span of twenty-two years from childhood into adulthood. These studies have controlled multiple variables including age, educational level, and initial level of aggressive behavior. Although not all studies have supported a causal link between television violence and aggressive behavior and attitudes, the large majority of laboratory experimental, field experimental, and correlational studies indicate that children do learn antisocial and aggressive behavior from televised violence and that some of them may directly imitate such behaviors. The effects depend on the characteristics of the viewers and the settings.

Not only have developmental methodologies been used after the fact to discover the effects of television programming, they also have been applied proactively to develop prosocial children’s programming, and then to evaluate the effects of those prosocial programs on children’s development. The program Sesame Street, for example, has as its foundation research into child development, attention, and learning. In fact, one of its objectives has been to act as an experimental variable, intervening into homes in which children are economically and educationally disadvantaged. Although researchers have had limited access to those high-risk homes, both experimental research and correlational longitudinal research support the effectiveness of Sesame Street in developing early academic skills, school readiness, positive attitudes toward school, and positive attitudes toward people of other races.

Evolution of Research

Today’s developmental methodologies have their origins in the nineteenth
century, with its advances in science and medicine, the emergence of the fields of
psychology and psychoanalysis, and developments in measurement and statistics.
Developmental psychological research and methodologies often emerged to deal with
concrete social problems. With compulsory education bringing approximately
three-quarters of all American children into classrooms at the beginning of the
twentieth century, social concerns were focused primarily on child health, education,
and social welfare. Consequently, the first major research into child intellectual,
social, and emotional development also occurred during this period, and developmental
psychology began to consolidate as a distinct discipline of
psychology.

The universal draft of World War I required assessment of multitudes of older adolescent and young adult men with vast differences in education, health status, and social and emotional stability. Standardized testing became the tool to evaluate these men, and it has remained a major tool in developmental methodologies, as well as in other disciplines of psychology. Following the war, efforts to understand these individual differences led to the first major longitudinal studies, which were focused on descriptions of normative growth and predictions of developmental patterns; some of these studies have followed their participants and next generations for more than fifty years.

In the two decades following World War II, the baby boom and national anxiety
over falling behind the Soviet Union in science and technology rekindled efforts
dampened during the war years in the disciplines of developmental and educational
psychology. Of particular interest were methodologies in applied settings such as
school classrooms, focused on learning and academic achievement. Also during this
period, greater accessibility to computers permitted increases in the complexity of
developmental research methods and designs, and of resultant data analyses. Complex
sequential designs, intricate correlational techniques, and multiple-variable techniques
became much more frequently used in research.

Heightened awareness of economic and social inequalities in the United States
following the Civil Rights movement led to many carefully designed educational, health,
social, and economic interventions into communities that were economically at risk. The
interventions were part of developmental methodologies in which experimental,
correlational, and descriptive data were collected longitudinally to assess their
outcomes. Head Start educational programs are one prominent example.

In more recent decades, with changes in family structure, developmental
methodologies have been applied to questions about single parenting, day care, and
“latch-key” children. With substance abuse, developmental methodologies have been
applied to questions about prenatal development in wombs of addicted mothers, postnatal
development of infants born drug-addicted, and developmental intervention for
drug-related disabilities in many of these infants. With more adults living longer and
healthier lives, developmental methodologies have been applied to questions about
learning and memory, self-esteem, and life satisfaction among persons in late adulthood.
Clearly, developmental methodologies will continue to be relevant as long as people are
motivated to understand and nurture healthy life-span development and to intervene into
social problems.

Bibliography

Laursen, Brett, and Todd D. Little.
Handbook of Developmental Research Methods. New York: Guilford,
2012. Print.

Miller, Scott A.
Developmental Research Methods. 3d ed. Thousand Oaks: Sage, 2007.
Print.

Mukherji, Penny, and Deborah Albon.
Research Methods in Early Childhood: An Introductory Guide. Los
Angeles: SAGE, 2010. Print.

Mussen, Paul Henry, ed.
Handbook of Research Methods in Child Development. New York: Wiley,
1960. Print.

Nielsen, Joyce McCarl, ed.
Feminist Research Methods: Exemplary Readings in the Social
Sciences. Boulder: Westview, 1990. Print.

Sears, Robert R. “Your
Ancients Revisited: A History of Child Development.” Feminist Research
Methods: Exemplary Readings in the Social Sciences. Vol. 5. Ed. E. M.
Hetherington. Chicago: U of Chicago P, 1975. Print.

Sommer, Barbara B., and
Robert Sommer. A Practical Guide to Behavioral Research: Tools and
Techniques. 5th ed. New York: Oxford UP, 2001. Print.

Thompson, Ross A. "Methods and Measures in
Developmental Emotions Research: Some Assembly Required." Jour. of
Experimental Child Psychology 110.2 (2011): 275–85. Print.

Triandis, H. C., and A.
Heron, eds. Basic Methods. Vol. 4. Handbook of
Cross-Cultural Psychology: Developmental Psychology. Boston: Allyn, 1981.
Print.

Wolman, Benjamin B., ed.
Handbook of Developmental Psychology. Englewood Cliffs: Prentice,
1982. Print.

Iodine-125 (125I) is used to treat, among other things, brain tumors and prostate cancer. It decays by gamma decay with a half-life of 54.90 days....

Half life is the amount of time after which only 50% of the original quantity remains. For example, the half life of Iodine-125 is 54.9 days. This means that after 54.9 days, half of the original implant value would have decayed. Similarly, after 2 half lives or 109.8 days (= 2 x 54.9 days), only 25% of the original content would be left. 

The initial decay rate or activity (A0) = 532 `mu`Ci, time period = 389 days.

Decay constant, `lambda`  = 0.693/T, where T = half life = 54.9 days

Using `A = A_0 e^(-lambdat)`

Solving for a time duration, t = 389 days, we get A = 3.92 `mu`Ci

For 16.5% of the initial value, A = 16.5% of A0 = 0.165 A0

Substituting this into the equation, we get

`A/A_0 = e^(-lambdat) = 0.165`

substituting the value of decay constant, we get, t = 142.74 days.

Assuming there are 30 days in a month, it will take about 4.76 months for the activity to be 16.5% of the initial value.

Hope this helps.

In the story, why did the man and his wife build fences and who were they afraid of?

In the story, the man and his wife have electronically-controlled gates installed and bars attached to the doors and windows of their home in order to prevent intruders from breaking in. After hearing about the many stories of mayhem on the streets, they are afraid of the violence unscrupulous rioters could unleash on them if they do not take the necessary precautions.

As the story progresses, we get the impression that everyone is afraid. Reports of burglaries and killings are so commonplace that everyone fears for their safety. To ensure the safety of the family, the man's mother-in-law sends extra bricks as a Christmas present; the bricks are to go towards building a higher wall around the house. When the family takes walks around the neighborhood, they notice that many other homes have installed the same walls. However, some have taken the extra precaution of embedding broken glass atop cemented walls or attaching sharp spikes to iron grills.

After seeing this, the man and his wife decide that they will also reinforce their own walls. Soon, they have razor-sharp coils attached to the whole length of the walls surrounding their property. The man and his wife are grateful for this added protection, but their happiness is short-lived when their own little son becomes entangled in the coils and suffers an excruciating death. Ironically, in trying to protect themselves, they become victims of their own precautions.

Why did Elizabeth I of England become a "virgin" queen, and why was it important to her? Thanks!

Elizabeth I of England (1533-1603) was called a "virgin" queen because she never married, despite her advisors urging her to do so to forge international alliances. However, there is evidence that she had many romantic relationships, including with Sir Walter Raleigh and Lord Dudley (later known as Earl of Leicester). Elizabeth's advisors also wanted her to marry to produce an heir, but she might have been eager to remain single because she had watched her father, Henry VIII, murder many of his wives. He had ordered Elizabeth's mother, Anne Boleyn, killed when Elizabeth was just two and a half. In addition, a married queen might have had to share power with her husband, and perhaps she was loathe to do so. Marriage also presented the possibility of anger among the nobles. For example, the nobility was opposed to her marriage to Lord Dudley, and she feared the loss of political power if she were to marry someone the nobles did not like. 

Is Jay Gatsby truly great?

I think it depends who you ask. If you ask Tom Buchanan, then no. Tom sees Gatsby only as a criminal who tries to break up his marriage. He also sees Gatsby as the man who cruelly hits his girlfriend, Myrtle Wilson, with his car without bothering to stop. Gatsby is a bad man and a bad person to Tom, not great at all.

By the end of the novel, I don't think Daisy Buchanan would say Gatsby is great either. Although she may truly have loved him once, it seems as though it's been a long time since Daisy learned to rank her wealth and status above anything having to do with her heart. When she learns Gatsby achieved his fortune illegally and is actually a criminal who can never replicate for her the elegant life she currently enjoys, she dumps him. 

To Nick Carraway, Gatsby is great. Nick sees Gatsby hold onto hope until the end; Gatsby always seems to believe that he might, one day, be able to have everything he's ever wanted—"It was an extraordinary gift for hope, a romantic readiness such as [Nick had] never found in any other person and which it is not likely [he] shall ever find again."  Gatsby has a kind of faith in his dreams that few adults have, and this makes him great to Nick.

In "A Retrieved Reformation" by O. Henry, what is Jimmy's attitude toward the warden?

Jimmy's attitude towards the warden is dismissive. He playfully mocks the warden by displaying nonchalance and faux innocence when the warden gives him some unsolicited advice.

According to the story, Jimmy has only served 'ten months of a four year sentence.' Because Jimmy has influential friends, his stints in prison always appear to be short. In Jimmy's eyes, he can afford to disregard the warden's impassioned advice. For his part, the warden thinks that Jimmy is a good man who just needs to buckle down and to 'live straight.'

In the conversation with the warden, Jimmy never takes the bait. He refuses to engage the warden in a discussion of his future. Each time the warden questions him about his motives or his part in a previous heist, Jimmy resorts to humor to distract the warden. In the end, the warden can only dismiss Jimmy with a blunt 'Better think over my advice, Valentine.' When Jimmy is released the next day, the warden shakes Jimmy's hand and hands him a cigar. With Jimmy's confident stance, we know that we haven't heard the last of this enigmatic character.

At some point in Harper Lee's To Kill a Mockingbird, the narrative's mood begins to shift. When and how does the mood change?

The narrative mood of Harper Lee's To Kill a Mockingbird certainly does shift noticeably at a certain point. For my part, I believe that the narrative's mood shifts at the beginning of Part Two, and I believe it changes by focusing less on the light-hearted coming-of-age aspects of the story and more on the complex and disturbing issues of race.

While the first part of the novel isn't always cheery, it does tend to be lighter than the second half of the novel. Most of the narrative focuses on Scout, Dill, and Jem's childhood games and the nostalgic world in which they occur. While they certainly run across issues of gender, race, class, and more, most of these worries are overshadowed by the exciting and imaginative world of carefree youth. With the beginning of the second part, however, the mood changes. We begin to learn more about Tom Robinson, and Scout and Jem begin to face more alienation from townsfolk angered at Atticus' role in the affair. As such, the mood of the second part gradually becomes darker and more convoluted, as Lee begins to focus more on issues of race and racism. As the novel goes on, the many social problems of Maycomb cannot be as easily swatted away by children's games. While the second part is still a coming-of-age tale, it focuses less on describing the cheery world of children and more on the troubled world of adults.

Why wasn't Holden at the big football game?

Holden gives two reasons for not attending the football game. The first is that he and the rest of the fencing team had gone to New York for a fencing competition. They were meant to be gone until the evening, but Holden forgot the fencing equipment on the subway and they had to return without getting to compete. Holden seems to think this is "pretty funny," but the rest of the team sure doesn't and "ostracizes" him the whole way back. 

Since the team was back in time for the game after all, Holden could have gone to it, but he goes instead to say goodbye to his history teacher, Mr. Spencer. Since Holden is being kicked out of Pencey, Spencer wanted to say goodbye and give him a lecture/pep talk about what he's doing with his life, which Holden hates. 

What are endorphins in the brain's reinforcement system?

Introduction

The term “endorphin” means “endogenous, morphine-like substance.” These naturally produced chemicals were discovered after researchers in the 1970s found that the opiate drugs morphine and heroin could physically bind to brain tissue. This binding occurred at neurochemical receptor sites on certain brain cells. Researchers began looking for the chemical that normally used these receptor sites, and soon discovered endorphins and their sister chemicals, the enkephalins. Collectively, these chemicals are referred to as endogenous opioids (opioid means opium-like). All are peptides, which consist of at least two amino acids linked together, and are often called opiate peptides. (Note that proteins, the body’s building blocks, consist of multiple peptides.) Some endogenous opioids function as neurotransmitters for communication between brain cells. Others function less for the communication of a specific message and more as modulators of a neuron’s response to yet other neurotransmitters.

The endorphins and other opioids are important because of their role in controlling pain, which has long been of interest to the medical profession.
Morphine, which chemically resembles the endorphins, was one of the first painkillers known to humankind. It is the active component of opium, and its effects have been recognized for centuries. Morphine is still widely used clinically for treating pain. Unfortunately, morphine is addictive and produces unpleasant withdrawal symptoms. Also, the body develops a tolerance to morphine so that ever-increasing doses are needed to control pain. Many other effective pain relievers have similar problems. The discovery of endorphins and enkephalins has provided hope that scientists will one day be able to control pain without fear of addiction or withdrawal symptoms after the treatment with the painkiller ends.

Beta Endorphins, Enkephalins, and Dynorphins

Endogenous opioids include alpha, beta, gamma, and delta endorphins; leucine and methionine enkephalin; dynorphins; and endomorphins. Most of these interact with three major subtypes of opioid receptors: mu, delta, and kappa. Of the endogenous opioids themselves, the beta-endorphins, the enkephalins, and the dynorphins have been most widely studied. The endorphins are the largest molecules in the endogenous opioid family, at about thirty amino acids long, while the enkephalins are shortest at about five amino acids long. Beta-endorphin and the dynorphins are more potent than the enkephalins and last longer in the body. Enkephalins are typically neurotransmitters, substances released by neurons that cause another nerve, muscle, or gland to respond to a given stimulus, of the brain and spinal cord. Though, weaker than endorphins, enkephalins are still considerably stronger and longer lasting than morphine.

The three primary types of endogenous opioids are distributed somewhat differently in the brain and spinal cord. The enkephalins and dynorphins are found primarily in the dorsal horn of the spinal cord, which receives incoming information, such as pain, from the body, and in the periaqueductal gray matter, which is part of the midbrain. Activation of the periaqueductal gray matter is clearly associated with analgesia for pain without affecting the person’s response to other touch-related sensations such as pressure and temperature. This area receives input from the frontal lobe, amygdala, and hypothalamus, structures involved in emotional expression, and projects to circuits in the brainstem that are involved with pain regulation. The periaqueductal gray matter also plays a role in species-specific behaviors such as predation and self-defense. Beta-endorphin is found most commonly in the hypothalamus, which projects to many other areas of the brain, including areas where enkephalins and dynorphins are found. Beta-endorphins in the brain are released in response to unpleasant stimuli entering the brain. In the spinal cord, they are released in response to impulses relayed from the brain to peripheral muscles.

The most widely studied effect of endogenous opioids such as the endorphins is their ability to block painful stimuli (the analgesic effect). However, they have been associated with many other physiological activities, including thermoregulation, appetite, emotion, memory, lipolysis, regulation of bowel movements, reproduction, and pleasurable experiences. They produce their effects by binding to target cells at receptor sites, which are protein structures of a particular size, shape, and chemical charge that can be activated only by specific chemicals. The receptor sites for the opioid peptides are the same ones that bind morphine, which allows the drug to produce effects similar to those produced by endogenous opioids.

Mechanism and Effects

The endorphins and other endogenous opioids appear to be inhibitory in nature. Activation of the opioid system increases inhibition in brain areas such as the periaqueductal gray matter, which in turn decreases the input the brain receives from the peripheral nervous system and the spinal cord. Thus, painful stimuli are blocked from reaching the upper brain. Morphine works the same way.

Although their effects are powerful, the endorphins and other endogenous opioids are typically found only in very low concentrations in nervous tissue. Because of this, most opioid research has been conducted in animals, in which cellular effects and injections into specific cells can be achieved. Animals, however, are unable to describe any feelings that might be produced. In humans, endorphins have generally been studied through plasma levels or cerebrospinal fluid levels.

Endorphins and other endogenous opioids are released in humans under conditions of physical or psychological stress. The physical stress most closely associated with an increase in plasma endorphin levels is aerobic exercise, especially running, although levels typically return to normal within thirty minutes to an hour after cessation of exercise. The endorphins are generally credited with decreased sensitivity to pain in athletes who suffer physical injury. They may also explain why some runners experience a feeling of well-being after prolonged, strenuous exercise.

Addiction and the Placebo Effect

The explanation for morphine addiction may also lie with opioids like the endorphins. Because morphine and the endorphins bind to the same receptors on cell membranes, the theory suggests that morphine, when available, occupies some of the receptor sites while the endorphins occupy the rest. This shuts down pain sensitivity. However, morphine and the other opiate drugs are exogenous (from outside) substances and are not as readily available to the individual as the endogenous opioids.

Furthermore, in patients to whom morphine is supplied, the natural circulating levels of the opioid enkephalins appear to decrease. Once enkephalin levels fall, the receptor sites to which they had been bound are no longer occupied, and pain stimuli can reach the brain. The increase in pain signals individuals to seek relief, and because they cannot increase their own endogenous opioids, they may take drugs such as morphine instead. This decrease in the circulation of natural opioids after morphine treatment may explain the phenomenon of drug craving and may partially explain morphine’s withdrawal effects.

Endogenous opioids are even involved in addictions to other substances, most notably alcohol. Alcohol appears to trigger the release of endogenous opioids, which produces some of the reinforcing effects of alcohol. Plus, abstinence from alcohol increases the numbers of certain opioid receptors in a brain structure called the nucleus accumbens, which is involved in reinforcement. The increase in opioid receptors caused by alcohol abstinence is associated with an increased craving for alcohol.

Endorphins also appear to be involved in the placebo effect. Patients who receive sugar in place of typical analgesics and are told they will feel better soon, often do experience an improvement in their condition. Research shows that the improvement brought about by a placebo can sometimes be blocked by injections of naloxone, which inhibits endogenous opioids. The belief that an analgesic will work apparently triggers the release of endogenous opioids and actually produces some pain relief, at least in some individuals.

Role of Stress and Exercise

Studies show that both animals and humans become less sensitive to painful stimuli while under stress. In humans, many instances have been described in which individuals experienced the severe stress of an injury without even being aware of the injury, or, if aware, without feeling the pain. For example, wounded soldiers sometimes claim to experience no pain from serious injuries, and sometimes even feel a sense of detachment or curiosity when viewing their wounds. Similarly, people show decreased pain sensitivity when engaged in the pleasant, but physically stressful, act of sexual intercourse. Much of this analgesic effect appears to be mediated by endogenous opioid release in the brain in response to pain. Drugs that block opioid receptors in the brain generally eliminate the decrease in pain sensitivity brought on by stressful events. Psychologically, this makes good sense. Pain is a warning to stay away from dangerous stimuli, but in individuals already fighting for their lives, pain is more of a distraction than an aid. For sexual intercourse, some experience of pain often occurs with the pleasure, but a species would not survive if the pain overcomes the reproductive drive.

Mood also can apparently be influenced by levels of endogenous opioids in the brain. Some badly injured people describe their mood as serene and accepting of the situation. More common experiences can alter mood in similar ways. One example is the athlete doing aerobic exercise. Strenuous exercise leads to physiological changes very similar to a stress reaction. Intense exercise, like that seen in long-distance running, can induce increases in naturally occurring opioids. Runners tested after a long run typically show elevated endorphin levels. Not only do they experience less pain, which is almost certainly an endorphin effect, but they sometimes experience a feeling of elation called the runner’s high.

Some scientists attribute the runner’s high to elevated endorphin levels. However, although endorphin levels remain elevated for only thirty minutes after a long run, the runner’s mood typically remains positive for far longer, indicating that factors other than endorphins, such as other brain chemicals and the psychological sense of accomplishment, probably play a role. Still, dedicated runners and others who regularly do aerobic exercise often describe a sense of loss when unable to run or exercise. Some researchers have suggested that this need to exercise resembles a form of exercise addiction and that the sense of loss can be seen as withdrawal from the person’s own endorphins. Exercise has even proven successful as a treatment for mildly depressed individuals, although whether this effect involves the endogenous opioids is unclear.

Animal Research

The best known effects of the endogenous opioids are their ability to induce analgesia and to reinforce behavior. However, other effects have also been observed. Many of these have been seen primarily in animals, and have not been clearly identified in humans. For example, rats injected with endogenous opioids during memory tasks generally show impaired performance. Rats show increased physical activity with low doses of endorphins but generally show decreased activity with higher doses. Rats also experience increased grooming tendencies and increased sexual arousal after treatment with opiate peptides, and the suckling behavior of rat pups is associated with elevated opioid levels.

Other animals also experience changes in behavior after administration of endogenous opioids. Young chicks isolated from their mother or from other young chicks normally give loud distress cries. This behavior decreases after endorphin administration, and similar effects have been seen in guinea pigs and dogs. Goldfish show increased schooling behavior when treated with endorphins, and wild, white-crowned sparrows increase feeding behavior when given endorphin injections, which may reflect a decrease in their stress response to being captured. Undoubtedly, other behavioral effects of endogenous opioids will be identified in animals in the future, and it is likely that correlates will be found for many of these behaviors in humans.

History of Opiate Studies

During the early 1970s, the US government declared a war on drugs. Federal money was made available to study the effects of drugs and the basis of drug addiction. The opiates, particularly heroin, were included in the targeted drug groups. It was theorized at the time that if the opiates had an effect on the brain, they must be operating on receptors. Some of these opiate-like receptors were isolated in 1973 at the Johns Hopkins University School of Medicine by Solomon H. Snyder and Candace Pert. The presence of natural opioid receptors in humans suggested the existence of endogenously occurring opiate-like substances, and the first such endogenous opioids were isolated and identified in 1973. It soon became clear that the existence of endogenous opioids such as the endorphins and enkephalins would revolutionize theories about the role of natural brain chemistry in drug addiction. It was not understood until much later how many other behaviors would also involve natural brain opioids.

The endogenous opioids remain a major area of study in neuroscience. A complete understanding of such phenomena as pain, stress, eating, addiction, reinforcement, sexual pleasure, and many other behaviors will require a more complete knowledge of the endorphins, enkephalins, dynorphins, and other endogenous opiate-like substances. The promise is great for developing better pain relievers and better treatments for stress and drug addiction. It remains to be seen whether the ability of these substances to alter mood will be a danger or a boon.

Bibliography

Carlson, Neil R. Physiology of Behavior. 11th ed. Boston: Allyn, 2012. Print.

Freye, Enno. Opioids in Medicine. New York: Springer, 2008. Print.

Gellman, Marc D., and J. Rick Turner. Encyclopedia of Behavioral Medicine. New York: Springer, 2013. Print.

Goldberg, Jeff. Anatomy of a Scientific Discovery. 25th anniversary ed. New York: Skyhorse, 2013. Print.

Lopez, Shane J. The Encyclopedia of Positive Psychology. Malden: Wiley, 2009. Print.

Meyer, Jerrold S., and Linda F. Quenzer. Psychopharmacology: Drugs, the Brain, and Behavior. Sunderland: Sinauer, 2005. Print.

Pasternak, Gavril W. The Opiate Receptors. New York: Humana, 2010. eBook Collection (EBSCOhost). Web. 20 May 2014.

Stannard, Cathy, Michael Coupe, and Tony Pickering. Opioids in Non-Cancer Pain. New York: Oxford UP, 2007. Print.

What are gallbladder diseases?

Causes and Symptoms

Gallbladder diseases affect a large number of people and are among the most common causes of abdominal pain. Most gallbladder problems stem from the presence of gallstones, which may be present in as many as one of every ten adults. In the past, anyone with gallstones was advised to have the gallbladder taken out, but this is no longer the case. It is now known that many people with gallstones never experience difficulty because of them.

A common gallbladder disease is biliary colic. This is usually manifested by severe right-sided, upper abdominal pain that is fairly repetitive. The pain may literally take the patient’s breath away, but an episode usually lasts less than thirty minutes. The patient may also complain of right-sided shoulder or back pain, often caused by irritation of the diaphragmatic nerves, which are located just above the liver on the right side. Many people may confuse the pain of biliary colic with indigestion, because in some patients it may be experienced in the middle of the upper abdomen. This pain is almost always brought on by eating, since the gallbladder contracts in response to food in the intestinal tract. The meal triggering such an episode often is described as rich and fatty, and many patients soon learn what types of food to avoid. Biliary colic does not occur unless gallstones are present, because they tend to obstruct the outflow of bile from the gallbladder. The initial treatment for biliary colic usually consists of dietary manipulation, that is, the avoidance of fatty foods or
other foods known to trigger the pain, but eventual recurrence and complications are likely, and elective removal of the gallbladder (cholecystectomy) is usually recommended.

When a diagnosis of gallstones is suspected, the physician will take down the patient’s medical history and perform a physical examination. In most cases, however, such actions will yield no physical findings that are indicative of gallstone disease. Thus the diagnosis is usually confirmed by an imaging study of the gallbladder, in which the gallstones are either directly or indirectly visualized. The most commonly used imaging modality is the ultrasound test, which can be easily and rapidly performed with very reliable results. While the gallstones cannot actually be seen, they have a density that reflects, rather than transmits, sound waves. As a result, they create specific echoes and shadows that can be interpreted by the radiologists as gallstones. No patient should be treated for gallstone disease without such imaging to confirm the presence of gallstones.

A potentially serious type of gallbladder disease caused by gallstones is acute
cholecystitis. In this condition, the outflow of bile is obstructed, usually by a gallstone that is stuck in the outflow tract, and severe inflammation and infection may develop. A patient with acute cholecystitis often complains of pain that does not go away promptly, may have chills or fever, and is usually found to have a very tender abdomen on the upper right side. The treatment of this condition is not controversial, and most physicians would probably recommend removing the gallbladder surgically. The only question remaining is whether the gallbladder should be removed immediately or electively, at a later date, if the patient recovers from acute cholecystitis with conservative management, including the use of antibiotics and the avoidance of eating until the inflammation subsides.

Inflammation and infection can also occur, although rarely, in gallbladders that do not produce gallstones. This happens in very select circumstances and is called acute acalculous cholecystitis. It usually afflicts very ill patients who have been in an intensive care unit for a long time, patients who have needed a heart-lung machine as a result of open heart surgery, or patients who are unable to eat for an extended period of time because of other problems. These patients are often fed only intravenously, which can lead to severe gallbladder problems. The exact mechanisms are not entirely known, but alterations in blood flow and an impaired ability to fight infection may play a role. Whatever the cause, the treatment often remains the same: removal of the gallbladder that does not respond to conservative therapy.

Gallstones can also move out of the gallbladder and cause serious problems. The main outflow tract of bile from the gallbladder and liver is the common bile duct, and this is a place gallstones frequently lodge. The end of this duct is surrounded by a small muscle called the sphincter of Oddi, which may not allow the passage of gallstones. If they become stuck there, they can completely obstruct the biliary system, and the patient will appear jaundiced. Removal of the gallstones will cure the problem. The presence of gallstones in the common bile duct is also associated with the development of pancreatitis, an inflammation of the pancreas that can be severe and life-threatening. Removal of the gallbladder at an appropriate time will prevent future bouts of pancreatitis.

The gallbladder can also be a source of cancer. Although cancer of the gallbladder is not common, it is estimated that one of every one hundred gallbladders removed will contain cancer. Therefore, all specimens removed must be examined by a qualified pathologist and all reports must be reviewed in their entirety by the surgeon. If the disease is limited to a minor thickness of the gallbladder, no further therapy is needed, but if the tumor is larger, further surgery—including removal of part of the liver—may be necessary. Gallbladder cancer grows silently in many patients, and it is often not detected until late in its course.

Treatment and Therapy

Because there is no simple way to prevent gallbladder problems, surgery plays a large role in their management. Removing the gallbladder, a relatively routine operation, results in a complete cure, with acceptably low complication rates and few long-term problems. While several exciting new ways of treating gallbladder and gallstone problems have been developed, the classic and standard method of therapy for gallbladder disease has been open cholecystectomy. This procedure entails making an incision across the upper right side of the abdomen a few inches below and parallel to the bottom of the rib cage. The muscles of the abdominal wall are cut, and the abdominal cavity is opened. The gallbladder, which is usually located right under this incision, is then removed and the incision closed in layers. This method of gallbladder removal has acceptable complication rates and is relatively safe and extremely effective. It allows the surgeon to inspect the entire abdomen and rule out other problems. One must consider, however, that this procedure constitutes major surgery. Most patients need to be in the hospital for a minimum of three to five days, and there is a considerable amount of
pain with this incision. These problems have prompted surgeons to find a less invasive way of removing the gallbladder, thereby achieving better pain control and reducing the length of the hospital stay and the time lost from work and other activities.

A laparoscope is an optical instrument, composed of a tube connected to a telescopic eyepiece, that allows the surgeon to perform a procedure inside the patient’s body. It has been employed in surgeries for many years, mainly in gynecological procedures, and has been widely adapted for removal of the gallbladder and for other types of surgeries. Laparoscopic cholecystectomy has become a procedure that all surgeons must know to stay current with the profession. The laparoscope and other surgical instruments are inserted directly into the abdomen through several small incisions, and the gallbladder is removed without a large incision having been made. The patients are often discharged the same day of the surgery, and they return to work much faster than with the open technique.

Despite its advantages, there are some pitfalls with laparoscopic cholecystectomy, and it cannot be used for all patients. There is an increased incidence of certain injuries to other organs and bile ducts at the time of the operation because less of the area can be seen than with an open operation. In addition, patients who have had previous upper abdominal surgery are not candidates for this procedure, and for those with acute cholecystitis, severe inflammation may make this technique unsafe. For most patients, however, laparoscopic cholecystectomy can be performed easily and safely with minimal complications and excellent results. It is becoming the standard of care and will continue to change the way gallbladder surgery is performed. The laparoscope is also being used to perform appendectomies, ulcer surgeries, cancer surveillance, and all types of intra-abdominal surgery.

Radiologists and internists may play an important role in the management of gallbladder disease. In certain circumstances, the techniques performed by these specialists may be indicated for extremely ill patients who might not be able to tolerate an operation, or for whom the anesthesia might be too hazardous. Invasive radiologists can actually place a tube into the gallbladder with help from their imaging equipment and remove infection or troublesome gallstones from the gallbladder. This procedure can alleviate symptoms in some patients, who may not even require any additional intervention. These practices are not common, however, and they are usually reserved for the very ill patient who might not survive an open operation or is at extremely high risk to develop a certain complication.

Gallstones can migrate out of the gallbladder and cause problems if they lodge in and obstruct the common bile duct. This places the patient at high risk for developing jaundice and infection in the biliary system. The standard method for dealing with this problem continues to be open surgery. In this procedure, the gallbladder is removed through an incision and the common bile duct is also opened. The gallstones are removed through a variety of techniques, and the duct is then closed. A tube is placed in the duct to keep it open, because otherwise it could scar and become narrowed. Many of these patients must be hospitalized for a number of days, making this surgery an expensive one.

Internists who specialize in the diseases of the abdomen have become proficient at performing endoscopic techniques. These techniques came about after the development of fiber
optics, which allow one to see through a tube, even if it is bent at a variety of angles. An endoscope, composed of surgical instruments, a light source, and fiber-optic cables, can be used to examine the lining of the stomach and intestines, allowing the diagnosis of many conditions.

Endoscopy is performed by inserting the endoscope through the mouth and into the patient’s stomach and the first part of the intestines. From this location, the area where the common bile duct opens into the intestines can be seen, and this is often where gallstones become lodged. The gallstones can be removed with instruments attached to the scope, thus solving the patient’s problem. Unfortunately, this technique does not remove the gallbladder, the source of the gallstones, and the patient is at some risk for a recurrence. This risk can be minimized by enlarging the opening where the duct enters the intestinal tract. This technique, too, is advantageous for patients who are elderly or ill and cannot withstand the trauma of surgery and anesthesia.

There are other options besides surgery or dietary changes for the treatment of patients with gallstones. Medicines are available that can dissolve the gallstones by changing the chemical nature and solubility of bile. Such drugs, however, are not ideal: They work only for certain types of gallstones, are expensive, and may produce side effects. In addition, there may be a recurrence of the gallstones when a patient stops taking these medicines. Such a result indicates that the bile-concentrating action of the gallbladder combines with a given patient’s bile composition to create a gallstone-forming environment. Thus, gallstones will continue to form unless the gallbladder is removed or the bile is again altered when the taking of such medicines is resumed. Patients can also have the gallstones broken up into very small pieces, as is often done with kidney stones, by high-frequency sound waves aimed at the gallstones. This procedure, however, known as
lithotripsy, has drawbacks: It works in only a small percentage of patients (those with a limited number of small gallstones), and the results have not been uniformly consistent or satisfactory.

Perspective and Prospects

Diseases of the gallbladder and biliary system are common in modern industrialized societies. The exact etiologies are not entirely clear, but they may involve dietary mechanisms or other customs of the Western lifestyle. There is also evidence that genetic factors are important, as gallbladder disease often runs in families. Traditionally, the treatment of non-life-threatening gallbladder disease has been conservative, with dietary discretion being the most important factor. When that failed, or if the condition was more serious, the gallbladder was removed.

Open cholecystectomy was long considered the best method for dealing with these problems. This operation has been recently challenged by endoscopic and laparoscopic techniques, which have become widely available and enjoyed great success. These new treatment options will become more important as increasing medical costs promote the refinement of less invasive and better techniques. Nevertheless, open cholecystectomy is sometimes the only option for a patient, and less invasive techniques can have limitations as well as complications.

Basic scientific research is also important in this field. Investigations into the mechanisms of gallstone formation are critical to the understanding of gallbladder diseases, as gallstones are the cause of many of these problems. As with many other diseases, prevention might be the key to eliminating many gallbladder diseases, making biliary colic, cholecystitis, and common bile duct diseases rare.

Bibliography:

Blumgart, L. H., and Y. Fong, eds. Surgery of the Liver and Biliary Tract. 3d ed. 2 vols. New York: W. B. Saunders, 2000.

Cameron, John L., and Andrew M. Cameron, eds. Current Surgical Therapy. 10th ed. Philadelphia: Mosby/Elsevier, 2011.

Choi, Young, and William B. Silverman. "Biliary Tract Disorders, Gallbladder Disorders, and Gallstone Pancreatitis." American College of Gastroenterology, Nov. 2008.

"Gallbladder Diseases." MedlinePlus, Apr. 8, 2013.

Krames Communications. The Gallbladder Surgery Book. San Bruno, Calif.: Author, 1991.

Krames Communications. Laparoscopic Gallbladder Surgery. San Bruno, Calif.: Author, 1991.

Porter, Robert S., et al., eds. The Merck Manual Home Health Handbook. 3d ed. Whitehouse Station, N.J.: Merck Research Laboratories, 2011.

Savitsky, Diane, and Marcin Chwistek. "Gallstones." Health Library, Sept. 30, 2012.

Zinner, Michael J., et al., eds. Maingot’s Abdominal Operations. 12th ed. New York: McGraw-Hill, 2013.

Describe 4 similarities between the onion cell root cell and whitefish blastula in mitosis.

There are many similarities between mitosis in plant cells, such as onion cells, and animal cells, such as whitefish blastula. The four steps of mitosis are prophase, metaphase, anaphase and telophase, and each of them occurs the same in plant and animal cells.

During prophase the chromosomes condense. During metaphase the chromosomes move to the middle of the cell and line up along the cell's equator. The chromosomes separate during anaphase, and in telophase two new nuclei begin to form. These processes are all the same in plant and animal cells.

One difference is that most plant cells don't have centrioles while animal cells do. Centrioles help organize the microtubules that make up the spindle fibers used to separate the duplicated chromosomes during anaphase. However, even though plant cells do not have centrioles they still use spindle fibers in the same way that animal cells do during mitosis. Cytokinesis, which occurs after mitosis, is also different in plant and animals cells. Because animal cells have a flexible cell membrane, the membrane pinches in to separate into two cell during cytokinesis. Plant cells have rigid cell walls, so a cell plate forms and builds into a cell wall that separates the cell into two cells during cytokinesis. 

What would be considered a cash cow for St. Jude's Children's Hospital?

To preface this complex question, the unique operating structure of St. Jude’s Children’s Hospital must first be addressed.  Unlike other hospitals and medical centers, St. Jude’s receives the majority of its financial support through public donations.  Indeed, an estimated 75% of contributions stem from private parties, with an estimated 12% coming from insurance companies, and another 10% coming from federal and association research grants.  With a budgeted daily operating cost of $2.2 million dollars, St. Jude relies heavily upon external contributions, as patients of St. Jude’s never receive a bill for treatments, travel, housing or food.  This means that St. Jude’s does not have the steady revenue stream of most research hospitals with charge-back policies.   

By definition, a “cash cow” is an entity that generates reliable revenue for a business or institution that exceeds the total amount of funds required to maintain daily operations.  The key word in the definition is reliable.  Public donations are often intermittent, varying in amounts and times, making it difficult for St. Jude’s to rely on fixed quarterly amounts.  Thus, two potential “cash cow” solutions are listed below.

1. 
   National Institutes of Health (NIH) Pediatric Research Grants.  Although St. Jude’s only receives 10% of funding from grants, if this percentage were to increase, St. Jude’s would have a more reliable budget for daily operations.  The NIH is the nation’s medical research agency that is part of the U.S. Department of Health and Human Services.  Therefore, it is federally backed, making its financial contributions more steady.  Further, the NIH helps connect research initiatives across the country, which in turn accelerates the progress of research and treatment solutions.  This solution would not only increase financial revenue, but would enhance the research programs at St. Jude’s.

1. 
   Development of Market Brands Specifically for St. Jude’s.  This “cash cow” solution hinges on the ability of St. Jude’s to gain support from mega-consumer corporations, such as McDonalds, Walmart, Macy’s, and C.V.S.  In this campaign, each corporation would have a high-in-demand product that is consistently bought by consumers and would designate a portion of the profit generated by that product to go to St. Jude’s.  For example, if McDonalds gave $0.05 of every fry sold or if Walmart gave $0.10 of every Walmart-brand Great Value paper towels sold to St. Jude’s, St. Jude’s would in turn have a steady stream of revenue.  Indeed, this idea does require the corporations to accept St. Jude’s as their philanthropic agency, but, if there is a program such as this in place, the corporations could focus on one amazing philanthropic opportunity while providing considerable financial support.  Also, this would work both ways.  A consumer is more likely to purchase a brand that gives back to those in need, thereby increasing the corporation’s sales.

Do the terms "shiny" and "flexible" describe physical or chemical properties of metals?

The terms "shiny" and "flexible" describe physical properties of metal. Physical properties are those which we might observe as general qualities of the metal when we look at it or manipulate it. We can look at a piece of metal and observe a reflective or lustrous quality which might make it look shiny. We might also try to bend or manipulate a piece of metal with our hands to gauge its malleability. Most metals are at least a little bit flexible, and if you'd like to observe this in your own home, you could try bending a piece of silverware or wire. Other physical properties of metal are its ability to conduct heat and electricity, and a solid-at-room-temperature form.

Chemical properties, on the other hand, have much more to do with the chemical or molecular composition of a metallic substance. For example, metals lose their valence electrons very easily. We cannot readily observe this with the naked eye, but it does happen and may eventually have some impact on the physical properties of the metal.

When does Miss Maudie show empathy in the novel To Kill a Mockingbird?

Miss Maudie exhibits empathy for Boo Radley in Chapter 5; she also exhibits this feeling for both Aunt Alexandra and Atticus in Chapter 24. 

Although the "foot-washing Baptists" rebuke Miss Maudie for her sins, she is truly a very charitable and warm-hearted woman who is much like a grandmother to Jem and Scout. Certainly, the children feel comfortable asking her just about anything because she replies honestly and with consideration for them. 
In Chapter 5 Scout inquires about Boo Radley and is first told that the man's name is Arthur. To her question about the possibility of Arthur's death, Miss Maudie replies that he is yet alive. She adds,

"Arthur Radley just stays in the house, that's all....Wouldn't you stay in the house if you didn't want to come out?"

She explains further that Mr. Radley is a hard man and that Arthur lives in "a sad house." She recalls that as a boy Arthur would always speak to her: "Spoke as nicely as he knew how." When Scout asks if Arthur may be crazy, Miss Maudie replies with genuine feeling and empathy for Arthur:

"If he's not, he should be by now....What happens in houses behind closed doors, what secrets--"

• Chapter 24

At the Missionary Tea, Mrs. Merriweather reveals her sanctimonious hypocrisy as she speaks of the great missionary work that Reverend J. Grimes Everett performs in Africa while she none-too-subtly reproves Atticus for seriously defending Tom Robinson:

"I tell you there are some good but misguided people in this town. Good, but misguided....some of 'em in this town thought they were doing the right thing a while back, but all they did was stir 'em up."

Because Mrs. Merriweather has made such insulting innuendos against Atticus in his own house and before his sister Alexandra, Miss Maudie fires back at her with a cynical remark, asking if Mr. Merriweather has his food sticking as he tries to swallow it ("His food doesn't stick going down, does it?"), implying that it must be difficult for him to eat food cooked by their black maid.

After this, Aunt Alexandra gives Miss Maudie "a look of pure gratitude" for her empathy. Later in the afternoon, Atticus comes home and announces to Alexandra and Miss Maudie that Tom Robinson has been shot trying to escape at the prison. He soon leaves, and Alexandra is very shaken by this terrible news. She tells Maudie that although she does not approve of all that Atticus has done, he is her brother and she worries about the stress that he is under: "It tears him to pieces....what else do they want from him, Maudie?"
With empathy, Miss Maudie replies, 

"Whether Maycomb knows it or not, we're paying the highest tribute we can pay a man. We trust him to do right." 

Alexandra asks, "Who?" and Miss Maudie replies, 

"The handful of people in this town who say that fair play is not marked White Only; the handful of people who say a fair trial is for everybody, not just us;....The handful of people in this town with background, that's who they are."

Having given Scout's aunt true moral support, Miss Maudie then suggests that they return to the ladies in the other room. Bolstered by Miss Maudie's support and empathy, Aunt Alexandra straightens her dress and re-assumes her role as hostess with renewed confidence.

Miss Maudie's wise and generous heart provides emotional support for members of the Finch family. This warm heart also extends its empathy to them and to others who need it, such as Boo Radley. 

In The Outsiders by S. E. Hinton, what are four conflicts that concern the Socs?

The Socs are continually fighting with the Greasers throughout the novel. The majority of their interactions result in violence, and both gangs hate one another. There are several scenes that depict the severity of the brawls involving the two gangs. Johnny is almost beaten to death, Bob Sheldon dies after attempting to drown Ponyboy, and Ponyboy suffers a concussion in the final rumble. The violent conflicts between the two gangs are significant to the plot of the novel.

One of the major conflicts concerning the Socs happens when one of their most respected gang members dies. Bob Sheldon was viewed as a leader in the gang and lost his life after Johnny stabbed him in self-defense. This tragic event only increases the tension between the two opposing gangs, which results in further violence. Losing one of their close friends affects each Soc differently and the traumatic event takes an emotional toll on the gang.

Another conflict involving the Socs concerns the loyalty of their members. Both Cherry Valance and Randy Adderson are jaded about their Soc lifestyle and choose to help the Greasers. Cherry Valance agrees to help spy on the Socs before the big rumble while Randy simply refuses to fight alongside his gang because he feels that fighting is useless.

There is also conflict regarding the Socs' personal relationships with their friends and families. Cherry tells Ponyboy that the Socs are aloof and superficial. She laments about how everyone lies to each other simply to keep up with appearances. Cherry understands that there is no real connection between her group of friends and describes it as one big rat race. Randy also tells Ponyboy that Bob Sheldon's parents kept giving him material things instead of teaching him that his actions had consequences. Randy explains that Soc parents are detached from their children and not aware of their extensive issues.

What is the psychology of affiliation and friendship?

Introduction

Affiliation is the desire or tendency to be with others of one’s own kind. Many animal species affiliate, collecting in groups to migrate or search for food. Human affiliation is not controlled simply by instinct but is affected by specific motives. One motivation for affiliation is fear: people seek the company of others when they are anxious or frightened. The presence of others may have a calming or reassuring influence. In 1959, research by social psychologist Stanley Schachter indicated that fear inducement leads to a preference for the company of others. Further work confirmed that frightened individuals prefer the company of others who are similarly frightened to the companionship of strangers. This preference for similar others suggests that affiliation is a source of information as well as reassurance.

Social Comparison Theory

The value of obtaining information through affiliating with others is suggested by social comparison theory. Social comparison is the process of comparing oneself with others in determining how to behave. According to Leon Festinger, who developed social comparison theory in 1954, all people have beliefs and place importance on the validity of their beliefs. Some beliefs can be verified objectively by consulting a reference such as a dictionary or a standard such as a yardstick. Others are subjective beliefs and cannot be verified objectively. In such cases, people look for consensual validation—the verification of subjective beliefs by obtaining a consensus among other people—to verify their beliefs. The less sure people are of the correctness of a belief, the more they rely on social comparison as a source of verification. The greater number of people there are who agree with one’s opinion about something, the more correct one feels in holding that opinion.

Influences on Affiliation

Beyond easing fear and satisfying the need for information or social comparison, mere affiliation with others is not usually a satisfactory form of interaction. Most people form specific attractions to other individuals rather than experiencing mere satisfaction with belonging to a group. These attractions usually develop into friendship, love, and other forms of intimacy. Interpersonal attraction—the experience of preferring to interact with specific others—is influenced by several factors. An important situational or circumstantial factor in attraction is propinquity, which refers to the proximity or nearness of other persons. Research by Festinger and his colleagues confirmed that people are more likely to form friendships with those who live nearby, especially if they have frequent accidental contact with them.

Further research by social psychologist Robert Zajonc indicated that propinquity increases attraction because it increases familiarity. Zajonc found that research subjects expressed greater liking for a variety of stimuli merely because they had been exposed to those stimuli more frequently than to others. The more familiar a person is, the more predictable that person seems to be. People are reassured by predictability and feel more strongly attracted to those who are familiar and reliable in this regard.

Another important factor in affiliation is physical attractiveness. A common stereotype about people who are considered physically attractive is that they are good and valuable in other ways. For example, physically attractive people are often assumed to be intelligent, competent, and socially successful. Attraction to physically attractive persons is somewhat modified by the fear of rejection. Consequently, most people use a matching principle in choosing friends and partners: They select others who match their own levels of physical attractiveness and other qualities.

Matching implies the importance of similarity. Similarity of attitudes, values, and background is a powerful influence on interpersonal attraction. People are more likely to become friends if they have common interests, goals, and pastimes. Similar values and commitments are helpful in establishing trust between two people. Over time, they choose to spend more time together, and this strengthens their relationship.

Another factor in interpersonal attraction is complementarity, defined as the possession of qualities that complete or fulfill another’s needs and abilities. Research has failed to confirm that “opposites attract,” since attraction appears to grow stronger with similarities, not differences, between two people. There is some evidence, however, that people with complementary traits and needs will form stronger relationships. For example, a person who enjoys talking will have a compatible relationship with a friend or partner who enjoys listening. Their needs are different but not opposite—they complement each other.

Friendship

Friendship begins as a relationship of social exchange. Exchange relationships involve giving and returning favors and other resources, with a short-term emphasis on maintaining fairness or equity. For example, early in a relationship, if one person does a favor for a friend, the friend returns it in kind. Over time, close friendships involve shifting away from an exchange basis to a communal basis. In a communal relationship, partners see their friendship as a common investment and contribute to it for their mutual benefit. For example, if one person gives a gift to a good friend, he or she does not expect repayment in kind. The gift represents an investment in their long-term friendship, rather than a short-term exchange.

Friendship also depends on intimate communication. Friends engage in self-disclosure and reveal personal information to one another. In the early stages of friendship, this is reciprocated immediately: one person’s revelation or confidence is exchanged for the other’s. As friendship develops, immediate reciprocity is not necessary; long-term relationships involve expectations of future responses. According to psychologist Robert Sternberg, friendship is characterized by two experiences: intimacy and commitment. Friends confide in one another, trust one another, and maintain their friendship through investment and effort.

Comfort in a Group

Theories of affiliation explain why the presence of others can be a source of comfort. In Schachter’s classic 1959 research on fear and affiliation, university women volunteered to participate in a psychological experiment. After they were assembled, an experimenter in medical attire deceived them by explaining that their participation would involve the administration of electrical shock. Half the subjects were told to expect extremely painful shocks, while the others were assured that the shocks would produce a painless, ticklish sensation. In both conditions, the subjects were asked to indicate where they preferred to wait while the electrical equipment was set up. Each could indicate whether she preferred to wait alone in a private room, preferred to wait in a large room with other subjects, or had no preference.

The cover story about electrical shock was a deception; no shocks were administered. The fear of painful shock, however, influenced the subjects’ preferences: Those who expected painful shocks preferred to wait with other subjects, while those who expected painless shocks expressed no preference. Schachter concluded that, as the saying goes, “misery loves company.” In a later study, subjects were given the choice of waiting with other people who were not research subjects. In this study, subjects who feared shock expressed specific preference for others who also feared shock: misery loves miserable company.

The social comparison theory of affiliation explains the appeal of group membership. People join groups such as clubs, organizations, and churches to support one another in common beliefs or activities and to provide one another with information. Groups can also be a source of pressure to
conform. One reason individuals feel pressured to conform with group behavior is that they assume the group has better information than they have. This is termed informational influence. Cohesive groups—those with strong member loyalty and commitment to membership—can also influence members to agree in the absence of information. When a member conforms with the group because he or she does not want to violate the group’s standards or norms, he or she has been subjected to normative influence.

Factors in Friendship

Studies of interpersonal attraction and friendship have documented the power of circumstances such as propinquity. In their 1950 book Social Pressures in Informal Groups, Festinger, Schachter, and Kurt Back reported the friendship preferences of married students living in university housing. Festinger and his colleagues found that the students and their families were most likely to form friendships with others who lived nearby and with whom they had regular contact. Propinquity was a more powerful determinant of friendship than common background or academic major. Propinquity appears to act as an initial filter in social relationships: nearness and contact determine the people an individual meets, after which other factors may affect interpersonal attraction.

The findings of Festinger and his colleagues can be applied by judiciously choosing living quarters and location. People who wish to be popular should choose to live where they will have the greatest amount of contact with others: on the ground floor of a high-rise building, near an exit or stairwell, or near common facilities such as a laundry room. Zajonc’s research on the power of exposure confirms that merely having frequent contact with others is sufficient to predispose them to liking.

Mere exposure does not appear to sustain relationships over time. Once people have interacted, their likelihood of having future interactions depends on factors such as physical attractiveness and similarity to one another. Further, the quality of their communication must improve over time as they engage in greater self-disclosure. As friends move from a tit-for-tat exchange to a communal relationship in which they both invest time and resources, their friendship will develop more strongly and satisfactorily.

Love

Research on love
has identified a distinction between passionate love and companionate love. Passionate love involves intense, short-lived emotions and sexual attraction. In contrast, companionate love is calmer, more stable, and based on trust. Companionate love is strong friendship. Researchers argue that if passionate love lasts, it will eventually transform into companionate love.

Researcher Zick Rubin developed a scale to measure love and liking. He found that statements of love involved attachment, intimacy, and caring. Statements of liking involved positive regard, judgments of similarity, trust, respect, and affection. Liking or friendship is not simply a weaker form of love but a distinctive combination of feelings, beliefs, and behaviors. Rubin found that most dating couples had strong feelings of both love and liking for each other; however, follow-up research confirmed that the best predictor of whether partners were still together later was how much they had liked—not loved—each other. Liking and friendship form a solid basis for love and other relationships that is not easily altered or forgotten.

Research

Much early research on affiliation and friendship developed from an interest in social groups. After World War II, social scientists were interested in identifying the attitudes and processes that unify people and motivate their allegiances. Social comparison theory helps to explain a broad range of behavior, including friendship choices, group membership, and proselytizing. Festinger suggested that group membership is helpful when one’s beliefs have been challenged or disproved. Like-minded fellow members will be equally motivated to rationalize the challenge. In their 1956 book When Prophecy Fails, Festinger, Henry Riecken, and Schachter document the experience of two groups of contemporary persons who had attested to a belief that the world would end in a disastrous flood. One group was able to gather and meet to await the end, while the other individuals, mostly college students, were scattered and could not assemble. When the world did not end as predicted, only those in the group context were able to rationalize their predicament, and they proceeded to proselytize, spreading the word to “converts.” Meanwhile, the scattered members, unable to rationalize their surprise, lost faith in the prophecy and left the larger group.

Friendship and love are challenging topics to study since they cannot be re-created in a laboratory setting. Studies of personal relationships are difficult to conduct in natural settings; if people know that others are observing while they talk or date, they behave differently or leave the scene. Natural or field studies are also less conclusive than laboratory research, since the factors that have produced the feelings or actions that can be observed are not always clear.

Friendship has not been as popular a topic in relationships research as romantic love, marriage, and sexual relationships. Some research has identified gender differences in friendship: Women communicate their feelings and experiences with other women, while men’s friendships involve common or shared activities. Developmental psychologists have also identified some age differences: Children are less discriminating about friendship, identifying someone as a friend who is merely a playmate; adults have more complex ideas about friendship forms and standards.

As research on close relationships has gained acceptance, work in communication studies has contributed to the findings of social psychologists. Consequently, more has been learned about the development and maintenance of friendship as well as the initial attractions and bonds that encourage people’s ties to others and reasons, such as neglect, for friendships ending. Studies consider friendships at various life stages, including middle and old age. Cultural changes affect relationship patterns, particularly by shaping people’s attitudes and motivations regarding affiliations. Modern examples of how culture affects affiliation include reality television programs that test alliances formed specifically for those competitions and the fact that some adolescents and young adults have “friends with benefits,” with whom they are intimate but not romantic.

Twenty-first-century psychology researchers studied childhood and adolescent friendships to gain new insights into the dynamics of those relationships. Psychologists focused on specific factors, motivating adolescents to develop and maintain friendships which had not been scientifically evaluated. Carnegie Mellon University researcher Vicki S. Helgeson and colleagues investigated how chronic health concerns affected friends. They studied relationships formed by healthy teenagers with diabetic girls and boys. The teenagers rated their friendships with individuals with similar or contrasting health status and from the same or opposite gender based on such issues as emotional support and conflict, specifying what they found appealing or not about those relationships. The researchers determined that health concerns did not significantly alter friendship patterns, although diabetic girls might desire more emotional support and appreciate more similar friends than their healthy peers would.

At the University of Missouri–Columbia, Amanda J. Rose evaluated survey responses by eight hundred female and male middle school students. The survey questioned students regarding their friendships, whether they divulged information about their problems, and if they had been anxious or depressed. The researchers determined that girls who shared their worries with friends benefited from strengthening those relationships but suffered emotional stress and depression if they fixated on problems too long, overanalyzing them and internalizing blame. Girls often became overwhelmed, concentrating emotions and energy on their problems instead of pursuing healthier endeavors. Rose referred to this dwelling behavior as corumination. Divulging their problems also enhanced friendships between boys. However, most boys did not experience similar psychological distress, perhaps because they did not blame themselves but accused others and external factors for causing conflicts in their lives.

Digitized Affiliation

By the early twenty-first century, digital technology altered how many people met and chose to pursue friendships and relationships or seek affiliation with groups. Although traditional psychological factors continued to shape social patterns, new technologies offered ways other than propinquity for people to encounter and contact others who shared interests or appealed to them. The Internet expanded people’s awareness of, and immediate access to, other cultures despite physical distances. Communication technology—especially cell phones, Blackberries, and iPhones—provided people the ability to contact friends, either vocally or by texting and e-mail, regardless of location or time. These communication forms often affected social relationships: people sometimes focused on texting and responding to electronic messages rather than interacting with people around them. Researchers have considered the psychological impact of the interference of digital communication with school, work, or sleep.

People formed affiliations by participating in virtual chat boards, support groups, or other Internet forums. Many people joined Internet dating sites to meet potential romantic partners in their communities or elsewhere. Some people designed avatars to represent them when gaming online or responding to blogs to communicate with virtual friends. The anonymity of the Internet enabled people to portray themselves, often deceptively, in ways they might be unable to in non-Internet affiliations. Abrupt familiarity often quickened the formation of friendships and sometimes presented emotional and, occasionally, physical dangers.

Social networking sites, including MySpace and Facebook, transformed how people perceived friendships. Created in 2004, Facebook initially formed communities of university students before eventually allowing other users to join. Most users of social networks chose to share their profile and information, including their romantic status, publicly instead of activating privacy settings. Each member acquired links to friends; in this case the concept of a friend was anybody the member approved who had requested to be a friend. Although most members had friends who were acquaintances, relatives, or friends of friends, other members acquired friends with whom they had no previous affiliation.

Researchers recognize the value of digital data available on social networking websites as useful for psychological analysis of affiliation and friendship connections. Protocol for studying humans participating in online social networks is vague; institutions sponsoring research have established various demands for psychology researchers, including requiring some researchers to acquire site or member permission. Researchers could study Facebook members’ public information to evaluate existing theories concerning popularity, self-esteem, identity, and relationships. For example, researchers at Harvard University and the University of California, Los Angeles used Facebook data to test a theory by Georg Simmel about triadic closure. Simmel hypothesized about friendships forming among an individual’s friends but was unable to acquire data to analyze his premise.

S. Shyam Sundar, of the Pennsylvania State University Media Effects Research Laboratory, studied how Facebook members’ friend quantities shape people’s opinions of those members’ possible psychological strengths or flaws. Eliot R. Smith, an Indiana University psychological and brain sciences specialist, secured a National Science Foundation grant to use Facebook data to interpret the processes involved in romances developing between strangers.

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