title: Infidelity

text: Differences in sexual infidelity as a function of gender have been commonly reported. It is more common for men compared to women to engage in extradyadic relationships. The National Health and Social Life Survey found that 4% of married men, 16% of cohabiting men, and 37% of dating men engaged in acts of sexual infidelity in the previous year compared to 1% of married women, 8% of cohabiting women, and 17% of women in dating relationships. These differences have been generally thought due to evolutionary pressures that motivate men towards sexual opportunity and women towards commitment to one partner (for reasons such as reproductive success, stability, and social expectations). In addition, recent research finds that differences in gender may possibly be explained by other mechanisms including power and sensations seeking. For example, one study found that some women in more financially independent and higher positions of power, were also more likely to be more unfaithful to their partners. In another study, when the tendency to sensation seek (i.e., engage in risky behaviours) was controlled for, there were no gender differences in the likelihood to being unfaithful. These findings suggest there may be various factors that might influence the likelihood of some individuals to engage in extradyadic relationships, and that such factors may account for observed gender differences beyond actual gender and evolutionary pressures associated with each.


title: Infidelity

text: There is currently debate in the field of evolutionary psychology whether an innate, evolved sex difference exists between men and women in response to an act of infidelity; this is often called a "sex difference". A study published in 2002 suggested there may be sex differences in jealousy. Those that posit a sex difference exists state that men are 60% more likely to be disturbed by an act of sexual infidelity (having one's partner engage in sexual relations with another), whereas women are 83% more likely to be disturbed by an act of emotional infidelity (having one's partner fall in love with another). Those against this model argue that there is no difference between men and women in their response to an act of infidelity. From an evolutionary perspective, men are theorized to maximize their fitness by investing as little as possible in their offspring and producing as many offspring as possible, due to the risk of males investing in children that are not theirs. Women, who do not face the risk of cuckoldry, are theorized to maximize their fitness by investing as much as possible in their offspring because they invest at least nine months of resources towards their offspring in pregnancy. Maximizing female fitness is theorized to require males in the relationship to invest all their resources in the offspring. These conflicting strategies are theorized to have resulted in selection of different jealousy mechanisms that are designed to enhance the fitness of the respective gender.


title: Infidelity

text: A common way to test whether an innate jealousy response exists between sexes is to use a forced-choice questionnaire. This style of questionnaire asks participants "yes or no" and "response A or response B" style questions about certain scenarios. For example, a question might ask, "If you found your partner cheating on you would you be more upset by (A) the sexual involvement or (B) the emotional involvement". Many studies using forced choice questionnaires have found statistically significant results supporting an innate sex difference between men and women. Furthermore, studies have shown that this observation holds across many cultures, although the magnitudes of the sex difference vary within sexes across cultures.


title: Infidelity

text: Although forced-choice questionnaires show a statistically significant sex-difference, critics of the theory of evolved sex differences in jealousy question these findings. In consideration of the entire body of work on sex differences, C. F. Harris asserted that when methods other than forced-choice questionnaires are used to identify an innate sex difference, inconsistencies between studies begin to arise. For example, researchers found that women sometimes report feeling more intense jealousy in response to both sexual and emotional infidelity. The results of these studies also depended on the context in which the participants were made to describe what type of jealousy they felt, as well as the intensity of their jealousy.


title: Infidelity

text: In her meta-analysis, Harris raises the question of whether forced choice questionnaires actually measure what they purport: jealousy itself and evidence that differences in jealousy arise from innate mechanisms. Her meta-analysis reveals that sex-differences are almost exclusively found in forced-choice studies. According to Harris, a meta-analysis of multiple types of studies should indicate a convergence of evidence and multiple operationalizations. This is not the case, which raises the question as to the validity of forced-choice studies. DeSteno and Bartlett (2002) further support this argument by providing evidence which indicates that significant results of forced-choice studies may actually be an artifact of measurement; this finding would invalidate many of the claims made by those "in favor" of an "innate" sex difference. Even those "in favor" of sex-differences admit that certain lines of research, such as homicide studies, suggest against the possibility of sex-differences.


title: Infidelity

text: These inconsistent results have led researchers to propose novel theories that attempt to explain the sex differences observed in certain studies. One theory that has been hypothesized to explain why men and women both report more distress to emotional infidelity than sexual infidelity is borrowed from childhood attachment theories. Studies have found that attachment styles of adults are consistent with their self-reported relationship histories. For example, more men are reported to have an insecure, dismissing avoidant attachment style; where these "individuals often attempt to minimize or constrict emotional experience, deny needs for intimacy, are highly invested in autonomy, and are more sexually promiscuous than individuals who have other attachment styles". Levy and Kelly (2010) tested this theory and found that adult attachment styles strongly correlate to which type of infidelity elicited more jealousy. Individuals who have secure attachment styles often report that emotional infidelity is more upsetting whereas dismissing attachment styles were more likely to find sexual infidelity more upsetting. Their study did report that men in general were more likely than women to report sexual infidelity as more distressing, however this could be related to more men having a dismissing attachment style.The authors propose that a social mechanism may be responsible for the observed results. In other words, replicable sex differences in emotion and sexual jealousy could be a function of a social function. Similar studies focusing on the masculinization and feminization by society also argue for a social explanation, while discounting an evolutionary explanation.


title: Infidelity

text: A 2015 study found a correlation between AVPR1A expression and predisposition to extrapair mating in women but not in men.


title: Infidelity

text: Evolutionary researchers have suggested that men and women have innate mechanisms that contribute to why they become sexually jealous, this is especially true for certain types of infidelity. It has been hypothesized that heterosexual men have developed an innate psychological mechanism that responds to the threat of sexual infidelity more than emotional infidelity, and vice versa for heterosexual women because potential cuckoldry is more detrimental to the male, who could potentially invest in offspring of another male, while for females emotional infidelity is more worrisome because they could lose the parental investment to another woman's offspring, therefore affecting their chances of survival. However, more recent studies suggest that increasingly both men and women would find emotional infidelity psychologically worse.


title: Infidelity

text: Symons (1979) determined that sexual jealousy is the major reason that many homosexual men are unsuccessful in maintaining monogamous relationships and suggests that all men are innately disposed to want sexual variation, with the difference between heterosexual and homosexual men being that homosexual men can find willing partners more often for casual sex, and thus satisfy this innate desire for sexual variety. However, according to this view, all men can be "hard wired" to be sexually jealous, and therefore gay men could be more upset by sexual infidelity than by emotional infidelity, and that lesbians could be more upset by emotional infidelity than sexual. Recent studies suggest that it may not be an innate mechanism, rather depends on the importance placed on sexual exclusivity. Peplau and Cochran (1983) found that sexual exclusivity was much more important to heterosexual men and women compared to homosexual men and women. This theory suggests that it is not sexuality that may lead to differences but that people are prone to jealousy in domains that are especially important to them. Barah and Lipton argue that heterosexual couples may cheat just as much as homosexual relationships.


title: Infidelity

text: Harris (2002) tested these hypotheses among 210 individuals: 48 homosexual women, 50 homosexual men, 40 heterosexual women, and 49 heterosexual men. Results found that more heterosexual than homosexual individuals picked sexual infidelity as worse than emotional infidelity, with heterosexual men being the highest, and that when forced to choose, gay men overwhelmingly predicted emotional infidelity would be more troubling than sexual infidelity. These findings contradict Symons (1979) suggestion that there would be no gender difference in predicted responses to infidelity by sexual orientation. Blow and Bartlett (2005) suggest that even though sex outside of a homosexual relationship might be seen as more acceptable in some relationships, the consequences of infidelity do not occur without pain or jealousy.


title: Infidelity

text: Heterosexuals rated emotional and sexual infidelity as more emotionally distressing than did lesbian and gay individuals. Sex and sexual orientation differences emerged regarding the degree to which specific emotions were reported in response to sexual and emotional infidelity. Few researchers have explored the influence of sexual orientation on which type of infidelity is viewed as more distressing.


title: Infidelity

text: Summarizing the findings from these studies, heterosexual men seem to be more distressed by sexual infidelity than heterosexual women, lesbian women, and gay men. These latter three groups seem more responsible for this difference by reporting similarly higher levels of distress toward emotional infidelity than heterosexual men. However, within-sex analyses reveal that heterosexual men tend to rate emotional infidelity as more distressing than sexual infidelity.


title: Infidelity

text: Some studies suggest that only a small percentage of couples that experience infidelity actually improve their relationship, whereas others report couples having surprisingly positive relationship outcomes. In terms of negative responses to infidelity, Charney and Parnass (1995) report that after hearing of a partner's infidelity, reactions have included rage and increased aggressiveness, loss of trust, decreased personal and sexual confidence, sadness, depression, damaged self-esteem, fear of abandonment, and a surge of justification to leave their partner. Another study reported that nearly 60% of the partners that were cheated on had emotional problems and depression following disclosure of the affair. Other negative consequences have included damage to relationships with children, parents, and friends, as well as legal consequences. A report in 1983 detailed that of a sample of 205 divorced individuals, about one half said their marital problems were caused by their spouse's infidelity.


title: Infidelity

text: The negative impact of infidelity on a relationship depends on how involved partners are in their infidelity relationship, and researchers maintain that infidelity itself does not cause divorce but the overall level of relationship satisfaction, motives for infidelity, level of conflict, and attitudes held about infidelity do. In fact, Schneider, et al. (1999) reported that even though 60% of their participants initially threatened to leave their primary relationship, a threat to leave due to infidelity did not actually predict the eventual outcome. Atkins, Eldridge, Baucom, and Christiansen found that couples who went through therapy as well as openly dealt with the infidelity were able to change at a faster rate than distressed couples who were just in therapy. Some unintended positive outcomes that have been reported for couples experiencing infidelity include closer marital relationships, increased assertiveness, taking better care of oneself, placing higher value on family, and realizing the importance of marital communication.


title: Infidelity

text: If divorce results from infidelity, research suggest that the "faithful" spouse may experience feelings of low life satisfaction and self-esteem; they may also engage in future relationships fearful of the same incidence occurring. Sweeney and Horwitz (2001) found that individuals who initiated a divorce after hearing about their partner's infidelity experienced less depression; however, the opposite was true when the offending spouse initiated divorce.


title: Infidelity

text: According to attachment theory, intimates evaluate the availability of close others and respond to them accordingly. While those with a secure attachment style believe others are available to them, those with insecure attachment believe others are less available to them. People who develop high levels of attachment have more anxiety and uncertainty. They cope by seeking reassurance and clinging themselves to another person. In attachment theory, people seek sex to help meet their needs. Those whose partners are unfaithful may experience anxiety, stress and depression. They are more likely to engage in activities that are risky to their health. Women who experienced negative appraisals, like self-blame and causal attribution, led to emotional distress and increased health-compromising behavior.


title: Infidelity

text: Gender self-esteem greatly affects infidelity. Different factors for the two genders are known to influence jealousy. Heterosexual men seem to be more distressed by sexual infidelity than heterosexual women, lesbian women, and gay men. The latter three groups seem more responsible for the difference by reporting similarly higher levels of distress toward emotional infidelity than heterosexual men.


title: Infidelity

text: Studies have found that men are more likely to engage in extramarital sex if they are unsatisfied sexually, while women are more likely to engage in extramarital sex if they are unsatisfied emotionally. Kimmel and Van Der Veen found that sexual satisfaction may be more important to husbands and that wives are more concerned with compatibility with their partners. Studies suggest that individuals who can separate concepts of sex and love are more likely to accept situations where infidelity occurs. One study done by Roscoe, Cavanaugh, and Kennedy found that women indicated relationship dissatisfaction as the number one reason for infidelity, whereas men reported a lack of communication, understanding, and sexual incompatibility. Glass and Wright also found that men and women who are involved in both sexual and emotional infidelities reported being the most dissatisfied in their relationships than those who engaged in either sexual or emotional infidelity alone. In general, marital dissatisfaction overall is the number one reason often reported for infidelity for both sexes.


title: Infidelity

text: It is important to note that there are many other factors that increase the likelihood of anyone engaging in infidelity. Individuals exhibiting sexually permissive attitudes and those who have had a high number of past sexual relationships are also more likely to engage in infidelity. Other factors such as being well educated, living in an urban centre, being less religious, having a liberal ideology and values, having more opportunities to meet potential partners, and being older affected the likelihood of one being involved in an extramarital affair.


title: Infidelity

text: Anthropologists tend to believe humans are neither completely monogamous nor completely polygamous. Anthropologist Bobbi Low says we are "slightly polygamous", while Deborah Blum believes we are "ambiguously monogamous", and slowly moving away from the polygamous habits of our evolutionary ancestors.


title: Infidelity

text: According to anthropologist Helen Fisher, there are numerous psychological reasons for adultery. Some people may want to supplement a marriage, solve a sex problem, gather more attention, seek revenge, or have more excitement in the marriage. But based on Fisher's research, there also is a biological side to adultery. "We have two brain systems: one of them is linked to attachment and romantic love, and then there is the other brain system, which is purely sex drive." Sometimes these two brain systems are not well-connected, which enables people to become adulterers and satisfy their libido without any regards to their attachment side.


title: Infidelity

text: Often, gender differences in both jealousy and infidelity are attributable to cultural factors. This variation stems from the fact that societies differ in how they view extramarital affairs and jealousy. An examination of jealousy across seven nations revealed that each partner in a relationship serves as each other's primary and exclusive source of satisfaction and attention in all cultures. Therefore, when an individual feels jealousy towards another, it is usually because they are now sharing their primary source of attention and satisfaction. However, variation can be seen when identifying the behaviors and actions that betray the role of primary attention (satisfaction) giver. For instance, in certain cultures if an individual goes out with another of the opposite gender, emotions of intense jealousy can result; however, in other cultures, this behavior is perfectly acceptable and is not given much thought.


title: Infidelity

text: It is important to understand where these cultural variations come from and how they root themselves into differing perceptions of infidelity. While many cultures report infidelity as wrong and admonish it, some are more tolerant of such behaviour. These views are generally linked to the overall liberal nature of the society. For instance, Danish society is viewed as more liberal than many other cultures, and as such, have correlating liberal views on infidelity and extramarital affairs. According to Christine Harris and Nicholas Christenfeld, societies that are legally more liberal against extramarital affairs judge less harshly upon sexual infidelity because it is distinct from emotional infidelity. In Danish society, having sex does not necessarily imply a deep emotional attachment. As a result, infidelity does not carry such a severe negative connotation. A comparison between modern-day Chinese and American societies showed that there was greater distress with sexual infidelity in the U.S. than in China. The cultural difference is most likely due to the more restrictive nature of Chinese society, thus, making infidelity a more salient concern. Sexual promiscuity is more prominent in the United States, thus it follows that American society is more preoccupied with infidelity than Chinese society. Often, a single predominant religion can influence the culture of an entire nation. Even within Christianity in the United States, there are discrepancies as to how extramarital affairs are viewed. For instance, Protestants and Catholics do not view infidelity with equal severity. The conception of marriage is also markedly different; while in Roman Catholicism marriage is seen as an indissoluble sacramental bond and does not permit divorce even in cases of infidelity, most Protestant denominations allow for divorce and remarriage for infidelity or other reasons. Ultimately, it was seen that adults that associated with a religion (any denomination) were found to view infidelity as much more distressing than those who were not affiliated with a religion. Those that participated more heavily in their religions were even more conservative in their views on infidelity.


title: Infidelity

text: Some research has also suggested that being African American has a positive correlation to infidelity, even when education attainment is controlled for. Other research suggests that lifetime incidence of infidelity does not differ between African Americans and whites, only the likelihood of when they engage in it. Race and gender have been found to be positively correlated with infidelity, however this is the case more often for African American men engaging in extramarital infidelity. Human mating strategies differ from culture to culture. For example, Schmitt discusses how tribal cultures with higher pathogen stress are more likely to have polygynous marriage systems; whereas monogamous mating systems usually have relatively lower high-pathogen environments. In addition researchers have also proposed the idea that high mortality rates in local cultures should be correlated with more permissive mating strategies. On the other hand, Schmitt discusses how demanding reproductive environments should increase the desire and pursuit of biparental, monogamous relationships.


title: Infidelity

text: Strategic pluralism is a theory that focuses on how environmental factors influence mating strategies. According to this theory, when people live within environments that are demanding and stressful, the need for bi-parental care is greater for increasing the survival of offspring. Correspondingly, monogamy and commitment are more commonplace. On the other hand, when people live within environments that encompass little stress and threats to the viability of offspring, the need for serious and committed relations is lowered, and therefore promiscuity and infidelity are more common.


title: Infidelity

text: Sex ratio theory is a theory that explains the relationship and sexual dynamics within different areas of the world based on the ratio of the number of marriage-aged men to marriage-aged women. According to this theory, an area has a high sex ratio when there is a higher number of marriage-aged women to marriage-aged men and an area has a low sex ratio when there are more marriage-aged men. In terms of infidelity, the theory states that when sex ratios are high, men are more likely to be promiscuous and engage in sex outside of a committed relationship because the demand for men is higher and this type of behavior, desired by men, is more accepted. On the other hand, when sex ratios are low, promiscuity is less common because women are in demand and since they desire monogamy and commitment, in order for men to remain competitive in the pool of mates, they must respond to these desires. Support for this theory comes from evidence showing higher divorce rates in countries with higher sex ratios and higher monogamy rates in countries with lower sex ratios.


title: Infidelity

text: While infidelity is by no means exclusive to certain groups of people, its perception can be influenced by other factors. Furthermore, within a "homogeneous culture", like that in the United States, factors like community size can be strong predictors of how infidelity is perceived. Larger communities tend to care less about infidelity whereas small towns are much more concerned with such issues. These patterns are observed in other cultures as well. For example, a cantina in a small, rural Mexican community is often viewed as a place where "decent" or "married" women do not go because of its semi-private nature. Conversely, public spaces like the market or plaza are acceptable areas for heterosexual interaction. A smaller population size presents the threat of being publicly recognized for infidelity. However, within a larger community of the same Mexican society, entering a bar or watering hole would garner a different view. It would be deemed perfectly acceptable for both married and unmarried individuals to drink at a bar in a large city. These observations can be paralleled to rural and urban societies in the United States as well. Ultimately, these variables and societal differences dictate attitudes towards sexual infidelity which can vary across cultures as well as within cultures.


title: Infidelity

text: "Mate poaching" is the phenomenon of a single person luring a person who is in an intimate relationship to leave their partner for the single person. According to a survey of 16,964 individuals in 53 countries by David Schmitt (2001), mate poaching happens significantly more frequently in Middle Eastern countries such as Turkey and Lebanon, and less frequently in East Asian countries such as China and Japan.


title: Infidelity

text: The parental investment theory is used to explain evolutionary pressures that can account for sex differences in infidelity. This theory states that the sex that invests less in the offspring has more to gain from indiscriminate sexual behaviour. This means that women, who typically invest more time and energy into raising their offspring (9 months of carrying offspring, breast feeding etc.), should be more choosy when it comes to mate selection and should therefore desire long-term, monogamous relationships that would ensure the viability of their offspring. Men on the other hand, have less parental investment and so they are driven towards indiscriminate sexual activity with multiple partners as such activity increases the likelihood of their reproduction. This theory says that it is these evolutionary pressures that act on men and women differentially and what ultimately drives more men to seek sexual activity outside of their own relationships. It can however, still account for the occurrence of extradyadic sexual relationships among women. For example, a woman whose husband has fertilization difficulties can benefit from engaging in sexual activity outside of her relationship. She can gain access to high-quality genes and still derive the benefit of parental investment from her husband or partner who is unknowingly investing in their illegitimate child. Evidence for the development of such a short-term mating strategy in women comes from findings that women who engage in affairs typically do so with men who are of higher status, dominance, physical attractiveness (which is indicative of genetic quality).


title: Infidelity

text: One defense mechanism that some researchers believe is effective at preventing infidelity is jealousy. Jealousy is an emotion that can elicit strong responses. Cases have been commonly documented where sexual jealousy was a direct cause of murders and morbid jealousy. Buss (2005) states that jealousy has three main functions to help prevent infidelity. These suggestions are:


title: Infidelity

text: Looking at jealousy's physiological mechanism offers support for this idea. Jealousy is a form of stress response which has been shown to activate the sympathetic nervous system by increasing heart rate, blood pressure, and respiration. This will activate the "fight or flight" response to ensure action against the attempt at sexual infidelity in their partner. Buss and his colleagues were the first to pioneer a theory that jealousy is an evolved human emotion that has become an innate module, hard-wired to prevent infidelity from occurring. This idea is commonly referred to as Jealousy as a Specific Innate Module and has become widely debated. The basis behind this argument is that jealousy was beneficial in our ancestor's time when cuckoldry was more common. They suggested that those who were equipped with this emotional response could more effectively stop infidelity and those without the emotional response had a harder time doing so. Because infidelity imposed such a fitness cost, those who had the jealous emotional response, improved their fitness, and could pass down the jealousy module to the next generation.


title: Infidelity

text: Another defense mechanism for preventing infidelity is by social monitoring and acting on any violation of expectations. Researchers in favor of this defense mechanism speculate that in our ancestor's times, the act of sex or emotional infidelity is what triggered jealousy and therefore the signal detection would have happened only after infidelity had occurred, making jealousy an emotional by-product with no selective function. In line with this reasoning, these researchers hypothesize that as a person monitors their partner's actions with a potential rival through primary and secondary appraisals; if their expectations are violated at either level of observation, they will become distressed and enact an appropriate action to stop the chance of infidelity. Social monitoring therefore enables them to act accordingly before infidelity occurs, thereby having the capability to raise their fitness. Research testing this theory has found more favor for the sexual jealousy hypothesis.


title: Infidelity

text: A more recently suggested defense mechanism of infidelity attracting more attention is that a particular social group will punish cheaters by damaging their reputation. The basis for this suggestion stems from the fact that humans have an unmatched ability to monitor social relationships and inflict punishment on cheaters, regardless of the context. This punishment comes in many forms, one of which is gossip. This damage will impair the future benefits that individual can confer from the group and its individuals. A damaged reputation is especially debilitating when related to sexual and emotional infidelity, because it can limit future reproductive mate choices within the group and will cause a net fitness cost that outweighs the fitness benefit gained from the infidelity. Such limitations and costs deter an individual from cheating in the first place. Support for this defense mechanism comes from fieldwork by Hirsch and his colleagues (2007) that found that gossip about extramarital affairs in a small community in Mexico was particularly prevalent and devastating for reputation in this region. Specifically, adultery was found to cause an individual to be disowned by their family, decrease the marriage value of his/her family, cause an individual to lose money or a job, and diminish future reproductive potential. In this community, men having extramarital affairs did so in private areas with lower prevalence of women connected to the community, such as bars and brothels, both areas of which had a high risk of contracting sexually transmitted infections.


title: Infidelity

text: The proliferation of sex chat rooms and dating apps has increased the opportunity for people in committed relationships to engage in acts of infidelity on and off the Internet. A cyber affair is defined as "a romantic or sexual relationship initiated by online contact and maintained primarily via online communication". Sexual acts online include behaviors such as cybersex, where two or more individuals engage in discussions about sexual fantasies over the Internet and is usually accompanied by masturbation; hotchatting, where discussions between two or more people move away from light-hearted flirting; and emotional acts where people disclose intimate information to a significant other. A new type of sexual activity online is when two people's avatars engage in sexual activity in virtual reality worlds such as "Second Life". The majority of Americans believe that if a partner engaged in cybersex this constitutes as an act of infidelity.


title: Infidelity

text: A 2005 survey of 1828 participants reported one third of them reported engaging in cybersex and of that one third, 46% said they were in a committed relationship with someone else.


title: Infidelity

text: In an attempt to differentiate offline and online infidelity, Cooper, Morahan-Martin, Mathy, and Maheu constructed a "Triple-A Engine", which identifies the three aspects of Internet infidelity that distinguish it, to some degree, from traditional infidelity:


title: Infidelity

text: In a study of 335 Dutch undergraduate students involved in serious intimate relationships, participants were presented with four dilemmas concerning a partner's emotional and sexual infidelity over the Internet. They found a significant sex difference as to whether participants chose sexual and emotional infidelity as more upsetting. More men than women indicated that a partner's sexual involvement would upset them more than a partner's emotional bonding with someone else. Similarly, in the dilemma involving infidelity over the Internet, more men indicated their partner's sexual involvement would upset them more than a partner's emotional bonding with someone else. Women, on the other hand, expressed more problems with emotional infidelity over the Internet than did men.


title: Infidelity

text: Online infidelity can be just as damaging to a relationship as offline physical unfaithfulness. A possible explanation is that our brain registers virtual and physical acts the same way and responds similarly. Several studies have concluded that online infidelity, whether sexual or emotional in nature, often leads to off-line infidelity.


title: Infidelity

text: A study by Beatriz Lia Avila Mileham in 2004 examined the phenomenon of online infidelity in chat rooms. The following factors were investigated: what elements and dynamics online infidelity involves and how it happens; what leads individuals specifically to the computer to search for a relationship "on the side"; whether individuals consider online contacts as infidelity and why or why not; and what dynamics chat room users experience in their marriages. The results led to three constructs that symbolize chat room dynamics and serve as a foundation for Internet infidelity:


title: Infidelity

text: All countries in Europe, as well as most countries in Latin America have decriminalized adultery; however, in many countries in Africa and Asia (particularly the Middle East) this type of infidelity is criminalized. Even where infidelity is not a criminal offense, it may have legal implications in divorce cases; for example it may be a factor in property settlement, the custody of children, the denial of alimony, etc. In civil claims, not only the spouse, but also the "other man/other woman" may be held accountable: for example, seven US states (Hawaii, Illinois, North Carolina, Mississippi, New Mexico, South Dakota, and Utah) allow the possibility of the tort action of alienation of affections (brought by a deserted spouse against a third party alleged to be responsible for the failure of the marriage). In a highly publicized case in 2010, a woman in North Carolina won a $9 million suit against her husband's mistress. In the United States, criminal laws relating to infidelity vary, and those states that criminalize adultery rarely prosecute the offense. Penalties for adultery range from life imprisonment in Michigan, to a $10 fine in Maryland or class 1 felony in Wisconsin. The constitutionality of US criminal laws on adultery is unclear due to Supreme Court decisions in 1965 giving privacy of sexual intimacy to consenting adults, as well as broader implications of "Lawrence v. Texas" (2003). Adultery is declared to be illegal in 21 states.


title: Infidelity

text: In many jurisdictions, adultery may have indirect legal implications, particularly in cases of infliction of violence, such as domestic assaults and killings, in particular by mitigating murder to manslaughter, or otherwise providing for partial or complete defenses in case of violence, especially in cultures where there is a traditional toleration of crimes of passion and honor killings. Such provisions have been condemned by the Council of Europe and the United Nations in recent years. The Council of Europe Recommendation Rec(2002)5 of the Committee of Ministers to member states on the protection of women against violence states that member states should: "(...) 57. preclude adultery as an excuse for violence within the family." UN Women has also stated in regard to the defense of provocation and other similar defenses: "Laws should clearly state that these defenses do not include or apply to crimes of 'honour', adultery, or domestic assault or murder."


title: Infidelity

text: As the number of women in the workforce increases to match that of men, researchers expect the likelihood of infidelity will also increase with workplace interactions. Wiggins and Lederer (1984) found that opportunities to engage in infidelity were related to the workplace where nearly one half of their samples who engaged in infidelity were involved with coworkers. A study done by McKinnish (2007) found that those who work with a larger fraction of workers of the opposite sex are more likely to be divorced due to infidelity. Kuroki found married women were less likely to have a workplace affair, whereas self-employed individuals are more likely. In 2000, Treas and Giesen found similar results where sexual opportunities in the workplace increased the likelihood of infidelity during the last 12 months.


title: Infidelity

text: Adulterous office romances are widely considered to be unhelpful to business and work relationships, and superior-subordinate relationships are banned in 90% of companies with written policies regarding office romance. Companies cannot ban adultery, as, in all but a handful of states, such regulations would run afoul of laws prohibiting discrimination on the basis of marital status. Firings nonetheless often occur on the basis of charges of inappropriate office conduct.


title: Infidelity

text: Academics and therapists say cheating is probably more prevalent on the road than close to home. The protection of the road offers a secret life of romance, far from spouses or partners. Affairs range from one-night stands to relationships that last for years. They are usually with a co-worker, a business associate or someone they repeatedly encounter.


title: Infidelity

text: Another reason for the development of office romances is the amount of time co-workers spend together. Spouses today often spend more time with co-workers in the office than with each other. A "Newsweek" article notes, "Nearly 60 percent of American women work outside the home, up from about 40 percent in 1964. Quite simply, women intersect with more people during the day than they used to. They go to more meetings, take more business trips and, presumably, participate more in flirtatious water-cooler chatter."


title: Infidelity

text: According to Debra Laino in an article for "Shave", some of the reasons women cheat at the workplace are because "women are disproportionately exposed to men in the workplace, and, as a direct consequence, many have more options and chances to cheat."


title: Infidelity

text: Swinging is a form of extradyadic sex where married couples exchange partners with each other. Swinging was originally called "wife-swapping", but due to the sexist connotations and the fact that many wives were willing to swap partners, "mate swapping" and or "swinging" was substituted. The Supreme Court in Canada has ruled swinging is legal as long as it takes place in a private place and is consensual. Swinging can be closed or open, where couples meet and each pair goes off to a separate room or they have sex in the same room. The majority of swingers fall into the middle and upper classes, with an above average education and income, and majority of these swingers are white (90%). A study done by Jenks in 1986 found that swingers are not significantly different from non-swingers on measures such as philosophy, authoritarianism, self-respect, happiness, freedom, equality etc. Swingers tend to emphasize personal values over more social ones. According to Henshel (1973), the initiation into the world of swinging usually is done by the husband.


title: Infidelity

text: Reasons for getting involved in swinging are the variety of sexual partners and experiences, pleasure or excitement, meeting new people, and voyeurism. In order for swinging to work, both partners need to have a liberal sexual predisposition, and a low degree of jealousy. Gilmartin (1975) found that 85% of his sample of swingers felt that these sexual encounters posed no real threat to their marriage and felt it had improved. Jenks (1998) found no reason to believe that swinging was detrimental to marriage, with over 91% of males and 82% of females indicating they were happy with swinging.


title: Infidelity

text: Another form of extradyadic sex is polyamory, a "non-possessive, honest, responsible and ethical philosophy and practice of loving multiple people simultaneously". There are various types of relationships in polyamory such as intentional family, group relationship, and group marriage. One type of group relationship can be a triad involving a married couple and an additional person who all share sexual intimacy, however, it is usually an addition of a female. Unlike polygyny or polyandry, both men and women may have multiple partners within the confines of polyamory. Polyamorous relationships are distinguished from extramarital affairs by the full disclosure and consent of all involved. Polyamorous relationships may specify unique boundaries outside monogamous expectations of fidelity, that if violated are still considered cheating. Because both men and women can have multiple partners, these individuals do not consider themselves to be either uncommitted or unfaithful.


title: A Dog's Purpose (film)

text: A Dog's Purpose is a 2017 American psychological comedy-drama adventure film directed by Lasse Hallström and written by W. Bruce Cameron, Cathryn Michon, Audrey Wells, Maya Forbes, and Wally Wolodarsky, based on the 2010 novel of the same name by W. Bruce Cameron. The film stars Britt Robertson, KJ Apa, Juliet Rylance, John Ortiz, Kirby Howell-Baptiste, Peggy Lipton, Dennis Quaid, and Josh Gad. The first film from the novel covers themes of loyalty, grief, dysfunctional family, and reincarnation from one to another lifetime.


title: A Dog's Purpose (film)

text: The film is a co-production between Amblin Entertainment, Reliance Entertainment, Walden Media, and Pariah Entertainment Group. It was released by Universal Pictures on January 27, 2017, and grossed $205 million worldwide. It was Peggy Lipton's final film role before her death in 2019.


title: A Dog's Purpose (film)

text: In the 1950s, a feral puppy wonders about life's true purpose. Weeks later, he is caught by dog catchers, whisked away to the pound, and euthanized.


title: A Dog's Purpose (film)

text: The dog is reborn as a Red Retriever in 1961. Leaving his cage at a puppy mill, he is taken by two garbage men who plan to sell him. Left locked inside their pick-up truck, he begins to die of heatstroke, but is rescued by a kindhearted mother and her eight-year-old son Ethan Montgomery. They break the truck's window and bring him home, naming him Bailey. Bailey and Ethan bond quickly, especially over the summer at Ethan's grandparents' farm, and Bailey decides Ethan alone is his purpose. Ethan gives him the nickname “Boss Dog”. Years pass, and after several attempts at advancing in his job fail, Ethan's father has become an alcoholic. In 1969, Ethan meets a girl named Hannah at a fair with Bailey, and they soon begin dating. They spend their summer together, happily though senior year. They plan to go to the same college, Ethan getting a football scholarship and Hannah with an academic one. At home one night, Ethan's drunken father becomes abusive towards his mother and him. Ethan orders him to leave and never return. Later in 1971 at a football game watched by scouts, Ethan is offered a full scholarship to Michigan State. That night, his vindictive classmate Todd throws a lit firecracker into Ethan's house, causing a house fire. Bailey alerts Ethan, who saves his mother out through an upstairs window. Ethan lowers her, then Bailey. However, he loses his rope and must jump, fracturing his leg and ending his athletic scholarship. Bailey attacks Todd, who is arrested by the police when firecrackers fall out of his pocket. Now, Ethan must go to an agricultural school, where he will learn to take over the farm. Depressed, Ethan breaks up with Hannah before leaving for college, while Bailey stays with Ethan's grandparents. Bailey ages and Ethan comes to say goodbye.


title: A Dog's Purpose (film)

text: Bailey is reborn as a female German Shepherd puppy, growing into a police dog named Ellie, in the late 1970s/early 1980s, while fully retaining memories of her past lives. Ellie is partnered with lonely officer Carlos Ruiz who has recently split up with his partner, of the Chicago Police Department and works hard at "seeking" and "finding", now seeing the job as life's purpose. They form a close bond, ending after Ellie saves a girl, kidnapped by her mother's ex-boyfriend, from drowning and is then fatally shot by the kidnapper while protecting Carlos.


title: A Dog's Purpose (film)

text: Reborn in the mid-1980s as a male Corgi, Bailey is adopted by Atlanta college student Maya, who names him Tino. Lonely, he tries to find her happiness. She meets Al, a classmate, after Tino falls for Al's dog, a female Landseer named Roxy. They marry, having three children. Tino is heartbroken when one day Roxy does not return from the vet. As a now elderly Tino dies, he thanks Maya for giving him one of his best lives.


title: A Dog's Purpose (film)

text: Bailey reincarnates again, this time as a St. Bernard/Australian Shepherd mix puppy in 2014. At first adopted by a woman named Wendi, he is named Waffles. Unfortunately, Wendi's husband neglects him, refuses to let her keep him inside, and after several years, abandons him. Waffles searches for a new life, gradually making his way back where he spent summers as Bailey. He joyfully reunites with his old master Ethan, now in his 60s, lonely on his grandparents' old farm, now his. Not recognizing him, Ethan takes him to the local animal shelter, but later reclaims him, naming him Buddy. Finally sensing that he has finally found his true purpose, he reunites Ethan with a widowed Hannah, and they get married. Buddy shows Ethan that he is his “Boss Dog”, by performing tricks and responding to phrases that were known only to the two of them many years back. Ethan finds Bailey's collar, now old and rusty, and places it back on Bailey's neck, and they resume playing exactly the way they did so long ago. Bailey narrates that life is about having fun, saving others, finding someone to be with, not getting upset over the past or the future, and living for today.


title: A Dog's Purpose (film)

text: In 2015, DreamWorks acquired the film rights for Cameron's novel. On May 8, 2015, it was announced Lasse Hallström would direct the film. On August 5, 2015, Britt Robertson and Dennis Quaid joined the cast. On September 18, 2015, Pooch Hall was cast in the film. On October 15, 2015, Bradley Cooper joined the cast to play Bailey's inner voice, but the role was eventually performed by Josh Gad. Principal photography began on August 17, 2015. During production, controversy ensued over treatment of a dog during filming.


title: A Dog's Purpose (film)

text: In December 2015, the film switched from a DreamWorks Pictures release to under the Amblin Entertainment banner as per Amblin Partners' newly enacted branded strategy. The film was released by Universal Pictures on January 27, 2017. Universal also distributed it overseas, except for countries where Mister Smith Entertainment handled international sales.


title: A Dog's Purpose (film)

text: "A Dog's Purpose" has grossed $64.5 million in the United States and Canada and $140.5 million in other territories for a worldwide gross of $205 million, against a production budget of $22 million.


title: A Dog's Purpose (film)

text: In North America, it was released alongside "" and "Gold", and was projected to gross $18–22 million from 3,050 theaters in its opening weekend, slightly lower than initial $27 million tracking had the film debuting to before boycotts against the film were called for. It made $466,000 from Thursday-night previews and $5.3 million on its first day. It ended up debuting to $18.2 million, finishing second at the box office behind the second weekend of Universal's own "Split". The film dropped 40.6% in its second weekend, grossing $10.8 million and finishing third at the box office.


title: A Dog's Purpose (film)

text: On Rotten Tomatoes, the film has an approval rating of 35% based on reviews from 142 critics, with an average rating of 4.8/10. The site's critics consensus reads, ""A Dog's Purpose" offers an awkward blend of sugary sentiment and canine suffering that tugs at animal-loving audiences' heartstrings with shameless abandon." On Metacritic, the film has a weighted average score of 43 out of 100 based on 32 critics, indicating "mixed or average reviews". Audiences polled by CinemaScore gave the film an average grade of "A" on an A+ to F scale.


title: A Dog's Purpose (film)

text: Andrew Barker of "Variety" wrote: "Viewed in a vacuum, it’s hard to fault the movie’s earnestness; Hallström’s canine cinema pedigree (which includes the superior "") shows through; and Rachel Portman's score is understandably sentimental without going completely saccharine."


title: A Dog's Purpose (film)

text: Frank Scheck of "The Hollywood Reporter" wrote: "While the human performers are more than adequate, there’s no doubt that the canine stars carry the day. Their utter irresistibility helps a long way in terms of getting past the corny plot machinations of "A Dog’s Purpose"."


title: A Dog's Purpose (film)

text: "A Dog's Purpose" was released on digital HD on April 18, 2017, and was followed by a release on Blu-ray and DVD on May 2, 2017, from Universal Pictures Home Entertainment. The film topped the home-video sales chart for the week ending on May 7, 2017.


title: A Dog's Purpose (film)

text: On January 18, 2017, a video surfaced on TMZ showing footage taken from the set of the film, which shows a male German Shepherd named Hercules being dragged and dipped into rushing water while visibly resisting. After a cut in the video, the next clip shows the dog being submerged in the water at the other end of the tank while a voice on set can be heard shouting "CUT IT!", and various people are then seen rushing towards the dog. The American Humane Association, which ensures that animals are not harmed in entertainment productions, announced that its representative on set had been suspended over the incident, and that the incident was under further investigation. PETA called for a boycott of the film. Actor Josh Gad, who voices the dog in the movie and was not on set during the making of the film, said he was "shaken and sad to see any animal put in a situation against its will." Director Lasse Hallström said via Twitter that he "did not witness" the actions in the video, and was "very disturbed" by the footage. Due to the release of the video, Universal Pictures cancelled the film's scheduled January 19 Los Angeles premiere.


title: A Dog's Purpose (film)

text: Amblin Entertainment released a statement in regards to the incident, saying, "on the day of the shoot, Hercules did not want to perform the stunt portrayed on the tape, so the Amblin production team did not proceed with filming that shot," and "Hercules is happy and healthy." On February 4, 2017, the American Humane Association reported that an independent third-party animal-cruelty expert had concluded that safety measures on the set of the film were in place and the video had been deliberately edited to mislead the public.


title: A Dog's Purpose (film)

text: On June 21, 2017, CEO of Amblin Entertainment Michael Wright announced that a sequel was in development. On August 26, 2018, Universal began production on the sequel, which is directed by Gail Mancuso, and was released on May 17, 2019. In addition to Quaid and Gad reprising their roles, the cast also includes Marg Helgenberger (replacing Peggy Lipton, who had become seriously ill), Betty Gilpin, Kathryn Prescott, and Henry Lau. The trailer for the sequel, titled" A Dog's Journey", was released in January 2019.


title: Meredith Hagner

text: Meredith Kathleen Hagner (born May 31, 1987) is an American actress. She began her career portraying Liberty Ciccone on the CBS soap opera "As the World Turns" (2008–2010), which earned her a Daytime Emmy Award nomination for Outstanding Younger Actress in a Drama Series in 2009. Following her departure from "As the World Turns", she appeared as a series regular on the FX drama "Lights Out" (2011) and the TBS sitcom "Men at Work" (2012–2014).


title: Meredith Hagner

text: Hagner gained further prominence for her role as Portia Davenport in the TBS / HBO Max dark comedy series "Search Party" (2016–2022), receiving critical praise for her performance. She also appeared as a series regular on the Facebook Watch comedy-drama "Strangers" (2017–2018) and the Quibi comedy "Dummy" (2020). Hagner's film roles include "Hits" (2014), "Folk Hero & Funny Guy" (2016), "The Oath" (2018), "Brightburn" (2019), and "Palm Springs" (2020).


title: Meredith Hagner

text: Hagner was born in New York City and grew up in Houston, Texas, and Chapel Hill, North Carolina. She attended Chapel Hill High School, graduating in 2005. She attended the Boston Conservatory for a year, but moved to New York after being offered acting opportunities. While in New York, she was cast in television and radio advertisements for 3M, Acuvue, JCPenney, Levi's, Radio Shack, Subway, and Truth.


title: Meredith Hagner

text: Hagner made her screen debut in the CBS daytime soap opera "As the World Turns" in 2008, as Liberty Ciccone, the illegitimate daughter of Brad Snyder and Janet Ciccone. She was nominated for a Daytime Emmy Award for Outstanding Younger Actress in a Drama Series in 2009. Hagner ended her two-year run as the character in March 2010, for a career on primetime television and feature film.


title: Meredith Hagner

text: Hagner starred in the FX short-lived 2011 drama series "Lights Out". She later was cast as lead on The CW pilot "Awakening", but it not was picked up to series. Hagner also appeared in a recurring role in the medical comedy "Royal Pains" on USA Network as Libby, a teenager with an extreme case of cyberchondria from 2009 to 2011, and guest-starred on "In Plain Sight", "", and "The Following". In 2012, Hagner began starring as Amy Jordan in the TBS comedy series "Men at Work". The series was canceled after three seasons in 2014.


title: Meredith Hagner

text: In 2016, Hagner returned to network television in TBS dark comedy "Search Party". Hagner stars in all five seasons as the accidentally investigative sidekick, Portia Davenport. Her portrayal of the shallow hipster actress was named by Rolling Stone magazine as one of the "20 Best TV Characters In 2016".


title: Meredith Hagner

text: Hagner began a relationship with actor Wyatt Russell after meeting on the set of the film "Folk Hero & Funny Guy" in 2015. They became engaged in December 2018 and married in 2019. In November 2020, the couple announced they were expecting their first child. Their son Buddy Prine Russell was born in March 2021.


title: BMW M52

text: The BMW M52 is a straight-6 DOHC petrol engine which was produced from 1994 to 2000. It was released in the E36 320i, to replace the M50. The BMW S52 engine is a high performance variant of the M52 which powered the American and Canadian market E36 M3 from 1996 to 1999.


title: BMW M52

text: In 1998, the "technical update" (M52TU) upgrades included adding variable valve timing to the exhaust camshaft.


title: BMW M52

text: The M52 was replaced by the M54 in the year 2000. The M52 and S52 engines were on the Ward's 10 Best Engines list from 1997 to 2000.


title: BMW M52

text: In most markets, the M52 switched from the M50's cast iron engine block to a lightweight aluminium engine block. However, most M52 engines produced for the United States and Canadian markets (except for those used by the BMW Z3 roadster) retained the M50's cast iron engine block, while other cars used the new aluminum M52 block with iron sleeves.


title: BMW M52

text: The largest version of the M52 is 2.8 litres, compared with 2.5 litres for the M50. As per the later versions of the M50, the M52 uses variable valve timing on the intake camshaft (called "single-VANOS"). The redline remained at 6,500 rpm.


title: BMW M52

text: In 1998, the "M52TU" ("Technical Update") was released, adding variable valve timing to the exhaust camshaft (called "double VANOS"). Other upgrades included a new design throttle body with the ASC (traction control) motor built in and throttle cable override, revised coolant passages with an additional drain back passage and a new cooling system with push fit hoses and a separate expansion tank plus a dual length intake manifold (called "DISA") and steel cylinder liners carried over from the previous M52, these replacing Nikasil in March 1998.


title: BMW M52

text: The version of the M52 debuted in 1995. It has a bore of , a stroke of and produces . The compression ratio is 10.2:1.


title: BMW M52

text: The aluminum M52 engine received criticism in some markets with high levels of sulfur in the petrol during the late 1990s. Sulfur has a corrosive effect on Nikasil and led to many early M52 and M60 engines having premature bore-liner wear. Countries with high sulfur fuel (such as the United States) received an iron block version of the M52 (except for the M52B28 in the Z3 which was an aluminium block), so the Nikasil problem does not apply to most M52 engines in these countries.


title: BMW M52

text: Once the Nikasil coating was determined to be the cause of the problem, steel cylinder liners were used instead of the Nikasil coating. Therefore, the M52TU engine was not affected by the Nikasil problem.


title: BMW M52

text: The S52 is a higher performance version of the M52, which replaced the S50B30US in the post-facelift (1996-1999) North American E36 M3.


title: BMW M52

text: Compared to the European-spec S50, the S52 is less powerful. The S52 also shares more in common with the regular M52 engine than the S50 did with the M50, for example sharing the engine block (cast iron, as per North American M52 engines) and cylinder head. Unique to the S52 is a bore of and stroke of for a total displacement of 3,152 cc. Compression ratio is 10.5:1. Other upgrades over the M52 include lighter camshafts (with increased lift and duration), valve springs and the exhaust system.


title: BMW M52

text: The S52 produces at 6,000 rpm and of torque at 3,800 rpm. The S52 has a redline of 7,000 rpm while the M52 has a 6,500 rpm redline.


title: DDR4 SDRAM

text: Double Data Rate 4 Synchronous Dynamic Random-Access Memory (DDR4 SDRAM) is a type of synchronous dynamic random-access memory with a high bandwidth ("double data rate") interface.


title: DDR4 SDRAM

text: Released to the market in 2014, it is a variant of dynamic random-access memory (DRAM), of which some have been in use since the early 1970s, and a higher-speed successor to the DDR2 and DDR3 technologies.


title: DDR4 SDRAM

text: DDR4 is not compatible with any earlier type of random-access memory (RAM) due to different signaling voltage and physical interface, besides other factors.


title: DDR4 SDRAM

text: DDR4 SDRAM was released to the public market in Q2 2014, focusing on ECC memory, while the non-ECC DDR4 modules became available in Q3 2014, accompanying the launch of Haswell-E processors that require DDR4 memory.


title: DDR4 SDRAM

text: The primary advantages of DDR4 over its predecessor, DDR3, include higher module density and lower voltage requirements, coupled with higher data rate transfer speeds. The DDR4 standard allows for DIMMs of up to 64 GB in capacity, compared to DDR3's maximum of 16 GB per DIMM.


title: DDR4 SDRAM

text: Unlike previous generations of DDR memory, prefetch has "not" been increased above the 8n used in DDR3; the basic burst size is eight 64-bit words, and higher bandwidths are achieved by sending more read/write commands per second. To allow this, the standard divides the DRAM banks into two or four selectable bank groups, where transfers to different bank groups may be done more rapidly.


title: DDR4 SDRAM

text: Because power consumption increases with speed, the reduced voltage allows higher speed operation without unreasonable power and cooling requirements.


title: DDR4 SDRAM

text: DDR4 operates at a voltage of 1.2 V with a frequency between 800 and 1600 MHz (DDR4-1600 through DDR4-3200), compared to frequencies between 400 and 1067 MHz (DDR3-800 through DDR3-2133) and voltage requirements of 1.5 V of DDR3. Due to the nature of DDR, speeds are typically advertised as doubles of these numbers (DDR3-1600 and DDR4-2400 are common, with DDR4-3200, DDR4-4800 and DDR4-5000 available at high cost). Unlike DDR3's 1.35 V low voltage standard DDR3L, there is no DDR4L low voltage version of DDR4.


title: DDR4 SDRAM

text: In April 2013, a news writer at International Data Group (IDG)an American technology research business originally part of IDCproduced an analysis of their perceptions related to DDR4 SDRAM. The conclusions were that the increasing popularity of mobile computing and other devices using slower but low-powered memory, the slowing of growth in the traditional desktop computing sector, and the consolidation of the memory manufacturing marketplace, meant that margins on RAM were tight.


title: DDR4 SDRAM

text: As a result, the desired premium pricing for the new technology was harder to achieve, and capacity had shifted to other sectors. SDRAM manufacturers and chipset creators were, to an extent, "stuck between a rock and a hard place" where "nobody wants to pay a premium for DDR4 products, and manufacturers don't want to make the memory if they are not going to get a premium", according to Mike Howard from iSuppli. A switch in consumer sentiment toward desktop computing and release of processors having DDR4 support by Intel and AMD could therefore potentially lead to "aggressive" growth.


title: DDR4 SDRAM

text: Intel's 2014 Haswell roadmap, revealed the company's first use of DDR4 SDRAM in Haswell-EP processors.


title: DDR4 SDRAM

text: DDR4 chips use a 1.2 V supply with a 2.5 V auxiliary supply for wordline boost called V, as compared with the standard 1.5 V of DDR3 chips, with lower voltage variants at 1.35 V appearing in 2013. DDR4 is expected to be introduced at transfer rates of 2133 MT/s, estimated to rise to a potential 4266 MT/s by 2013. The minimum transfer rate of 2133 MT/s was said to be due to progress made in DDR3 speeds which, being likely to reach 2133 MT/s, left little commercial benefit to specifying DDR4 below this speed. Techgage interpreted Samsung's January 2011 engineering sample as having CAS latency of 13 clock cycles, described as being comparable to the move from DDR2 to DDR3.


title: DDR4 SDRAM

text: Increased memory density is anticipated, possibly using TSV ("through-silicon via") or other 3D stacking processes. The DDR4 specification will include standardized 3D stacking "from the start" according to JEDEC, with provision for up to dies. X-bit Labs predicted that "as a result DDR4 memory chips with very high density will become relatively inexpensive".


title: DDR4 SDRAM

text: In 2008 concerns were raised in the book "Wafer Level 3-D ICs Process Technology" that non-scaling analog elements such as charge pumps and voltage regulators, and additional circuitry "have allowed significant increases in bandwidth but they consume much more die area". Examples include CRC error-detection, on-die termination, burst hardware, programmable pipelines, low impedance, and increasing need for sense amps (attributed to a decline in bits per bitline due to low voltage). The authors noted that, as a result, the amount of die used for the memory array itself has declined over time from 70–78% for SDRAM and DDR1, to 47% for DDR2, to 38% for DDR3 and to potentially less than 30% for DDR4.


title: DDR4 SDRAM

text: The specification defined standards for ×4, ×8 and ×16 memory devices with capacities of 2, 4, 8 and 16 Gbit.


title: DDR4 SDRAM

text: Although it still operates in fundamentally the same way, DDR4 makes one major change to the command formats used by previous SDRAM generations. A new command signal, , is low to indicate the activate (open row) command.


title: DDR4 SDRAM

text: The activate command requires more address bits than any other (18 row address bits in a 16 Gbit part), so the standard , , and active low signals are shared with high-order address bits that are not used when is high. The combination of =L and ==H that previously encoded an activate command is unused.


title: DDR4 SDRAM

text: As in previous SDRAM encodings, A10 is used to select command variants: auto-precharge on read and write commands, and one bank vs. all banks for the precharge command. It also selects two variants of the ZQ calibration command.


title: DDR4 SDRAM

text: As in DDR3, A12 is used to request "burst chop": truncation of an 8-transfer burst after four transfers. Although the bank is still busy and unavailable for other commands until eight transfer times have elapsed, a different bank can be accessed.


title: DDR4 SDRAM

text: Also, the number of bank addresses has been increased greatly. There are four bank select bits to select up to 16 banks within each DRAM: two bank address bits (BA0, BA1), and two bank group bits (BG0, BG1). There are additional timing restrictions when accessing banks within the same bank group; it is faster to access a bank in a different bank group.


title: DDR4 SDRAM

text: In addition, there are three chip select signals (C0, C1, C2), allowing up to eight stacked chips to be placed inside a single DRAM package. These effectively act as three more bank select bits, bringing the total to seven (128 possible banks).


title: DDR4 SDRAM

text: Standard transfer rates are 1600, 1866, 2133, 2400, 2666, 2933, and 3200 MT/s (, , , , , , and  GHz clock frequencies, double data rate), with speeds up to DDR4-4800 (2400 MHz clock) commercially available.


title: DDR4 SDRAM

text: Rowhammer mitigation techniques include larger storage capacitors, modifying the address lines to use address space layout randomization and dual-voltage I/O lines that further isolate potential boundary conditions that might result in instability at high write/read speeds.


title: DDR4 SDRAM

text: DDR4 memory is supplied in 288-pin dual in-line memory modules (DIMMs), similar in size to 240-pin DDR3 DIMMs. The pins are spaced more closely (0.85 mm instead of 1.0) to fit the increased number within the same 5¼ inch () standard DIMM length, but the height is increased slightly ( instead of ) to make signal routing easier, and the thickness is also increased (to 1.2 mm from 1.0) to accommodate more signal layers. DDR4 DIMM modules have a slightly curved edge connector so not all of the pins are engaged at the same time during module insertion, lowering the insertion force.


title: DDR4 SDRAM

text: DDR4 SO-DIMMs have 260 pins instead of the 204 pins of DDR3 SO-DIMMs, spaced at 0.5 rather than 0.6 mm, and are 2.0 mm wider (69.6 versus 67.6 mm), but remain the same 30 mm in height.


title: DDR4 SDRAM

text: For its Skylake microarchitecture, Intel designed a SO-DIMM package named UniDIMM, which can be populated with either DDR3 or DDR4 chips. At the same time, the integrated memory controller (IMC) of Skylake CPUs is announced to be capable of working with either type of memory. The purpose of UniDIMMs is to help in the market transition from DDR3 to DDR4, where pricing and availability may make it undesirable to switch the RAM type. UniDIMMs have the same dimensions and number of pins as regular DDR4 SO-DIMMs, but the edge connector's notch is placed differently to avoid accidental use in incompatible DDR4 SO-DIMM sockets.


title: DDR4 SDRAM

text: DDR4-xxxx denotes per-bit data transfer rate, and is normally used to describe DDR chips. PC4-xxxxx denotes overall transfer rate, in megabytes per second, and applies only to modules (assembled DIMMs). Because DDR4 memory modules transfer data on a bus that is 8 bytes (64 data bits) wide, module peak transfer rate is calculated by taking transfers per second and multiplying by eight.


title: DDR4 SDRAM

text: At the 2016 Intel Developer Forum, the future of DDR5 SDRAM was discussed. The specifications were finalized at the end of 2016 but no modules will be available before 2020. Other memory technologies namely HBM in version 3 and 4 aiming to replace DDR4 have also been proposed.


title: DDR4 SDRAM

text: In 2011, JEDEC published the Wide I/O 2 standard; it stacks multiple memory dies, but does that directly on top of the CPU and in the same package. This memory layout provides higher bandwidth and better power performance than DDR4 SDRAM, and allows a wide interface with short signal lengths. It primarily aims to replace various mobile DDR"X" SDRAM standards used in high-performance embedded and mobile devices, such as smartphones. Hynix proposed similar High Bandwidth Memory (HBM), which was published as JEDEC JESD235. Both Wide I/O 2 and HBM use a very wide parallel memory interface, up to 512 bits wide for Wide I/O 2 (compared to 64 bits for DDR4), running at a lower frequency than DDR4. Wide I/O 2 is targeted at high-performance compact devices such as smartphones, where it will be integrated into the processor or system on a chip (SoC) packages. HBM is targeted at graphics memory and general computing, while HMC targets high-end servers and enterprise applications.


title: DDR4 SDRAM

text: Micron Technology's Hybrid Memory Cube (HMC) stacked memory uses a serial interface. Many other computer buses have migrated towards replacing parallel buses with serial buses, for example by the evolution of Serial ATA replacing Parallel ATA, PCI Express replacing PCI, and serial ports replacing parallel ports. In general, serial buses are easier to scale up and have fewer wires/traces, making circuit boards using them easier to design.


title: DDR4 SDRAM

text: In the longer term, experts speculate that non-volatile RAM types like PCM (phase-change memory), RRAM (resistive random-access memory), or MRAM (magnetoresistive random-access memory) could replace DDR4 SDRAM and its successors.


title: DDR4 SDRAM

text: GDDR5 SGRAM is a graphics type of DDR3 synchronous graphics RAM, which was introduced before DDR4, and is not a successor to DDR4.


title: Monument Valley

text: Monument Valley (, , meaning "valley of the rocks") is a region of the Colorado Plateau characterized by a cluster of sandstone buttes, the largest reaching above the valley floor. It is located on the Utah-Arizona state line, near the Four Corners area. The valley is a sacred area that lies within the territory of the Navajo Nation Reservation, the Native American people of the area.


title: Monument Valley

text: Monument Valley has been featured in many forms of media since the 1930s. Director John Ford used the location for a number of his Westerns; critic Keith Phipps wrote that "its have defined what decades of moviegoers think of when they imagine the American West."


title: Monument Valley

text: The area is part of the Colorado Plateau. The elevation of the valley floor ranges from above sea level. The floor is largely siltstone of the Cutler Group, or sand derived from it, deposited by the meandering rivers that carved the valley. The valley's vivid red color comes from iron oxide exposed in the weathered siltstone. The darker, blue-gray rocks in the valley get their color from manganese oxide.


title: Monument Valley

text: The buttes are clearly stratified, with three principal layers. The lowest layer is the Organ Rock Shale, the middle is de Chelly Sandstone, and the top layer is the Moenkopi Formation capped by Shinarump Conglomerate. The valley includes large stone structures, including the "Eye of the Sun".


title: Monument Valley

text: Between 1945 and 1967, the southern extent of the Monument Upwarp was mined for uranium, which occurs in scattered areas of the Shinarump Conglomerate; vanadium and copper are associated with uranium in some deposits.


title: Monument Valley

text: Monument Valley includes much of the area surrounding Monument Valley Navajo Tribal Park, a Navajo Nation equivalent to a national park. Oljato, for example, is also within the area designated as Monument Valley.


title: Monument Valley

text: Visitors may pay an access fee and drive through the park on a dirt road. Parts of Monument Valley, such as Mystery Valley and Hunts Mesa, are accessible only by guided tour.


title: Monument Valley

text: Monument Valley experiences a desert climate with cold winters and hot summers. While the summers may be hot, the heat is tempered by the region's high altitude. Although the valley experiences an average of 54 days above annually, summer highs rarely exceed . Summer nights are comfortably cool, and temperatures drop quickly after sunset. Winters are cold, but daytime highs are usually above freezing. Even in the winter, temperatures below are uncommon, though possible. Monument Valley receives an occasional light snowfall in the winter; however, it usually melts within a day or two.


title: Monument Valley

text: Monument Valley has been featured in numerous computer games, in print, and in motion pictures, including multiple Westerns directed by John Ford that influenced audiences' view of the American West, such as: "Stagecoach" (1939), "My Darling Clementine" (1946), "Fort Apache" (1948), "She Wore a Yellow Ribbon" (1949) and "The Searchers" (1956).


title: Monument Valley

text: Many more recent movies, with other directors, were also filmed in Monument Valley, including Sergio Leone's "Once Upon a Time in the West" (in 1967), the first Spaghetti Western to be filmed outside Europe, and Gore Verbinski's "The Lone Ranger".


title: Monument Valley

text: In Airwolf: The Movie and the subsequent series, a hollow mesa in Monument Valley was the hiding place for the fictional helicopter. It was referred to as 'Valley of the Gods'.


title: Jimmy Somerville

text: James William Somerville (born 22 June 1961) is a Scottish pop singer and songwriter. He sang in the 1980s with the pop groups Bronski Beat and The Communards, and has also had a solo career. He is known in particular for his powerful and soulful countertenor/falsetto singing voice. Many of his songs, such as "Smalltown Boy", contain political commentary on gay-related issues.


title: Jimmy Somerville

text: Born on 22 June, 1961, James William Somerville grew up in Ruchill, a neighbourhood of northern Glasgow. In 1980 he moved to London, where he lived in squats. He immersed himself in gay culture, and attended the London Gay Teenage Group.


title: Jimmy Somerville

text: In 1983, Somerville co-founded the synthpop group Bronski Beat, which had several hits in the British charts. Their biggest hit was "Smalltown Boy", which reached No. 3 in the UK charts. In the music video Somerville plays the song's titular character, who leaves his hostile hometown for the friendlier city, reflecting Somerville's own experiences when he moved to London.


title: Jimmy Somerville

text: Somerville left Bronski Beat in 1985 and formed The Communards with classically-trained pianist Richard Coles, who became a Church of England vicar (retired, April 2022) and broadcaster. They had several hits, including a cover version of Harold Melvin & the Blue Notes' "Don't Leave Me This Way", which spent four weeks at No. 1 in the UK charts and became the biggest-selling single of 1986 in the UK. He also sang backing vocals on Fine Young Cannibals' version of "Suspicious Minds", which was a UK Top 10 hit.


title: Jimmy Somerville

text: The Communards split in 1988; Somerville began a solo career the following year. He released his debut solo album "Read My Lips" in November 1989, which contained three UK Top 30 hits, including a hit cover of Sylvester's disco classic "You Make Me Feel (Mighty Real)" and a cover of "Comment te dire adieu?", a duet with June Miles-Kingston, which reached number 14 in the UK Singles chart. He also sang on the second Band Aid project at the end of 1989.


title: Jimmy Somerville

text: In November 1990, Somerville's greatest-hits album "The Singles Collection 1984/1990" (which featured his hits with Bronski Beat and The Communards in addition to his own material) was released; it reached number 4 on the UK Album Chart. It included a reggae cover of the Bee Gees' hit song "To Love Somebody", which also reached the UK Top 10. Also in 1990, Somerville contributed the song "From This Moment On" to the Cole Porter tribute album "Red Hot + Blue" produced by the Red Hot Organization, the proceeds from which benefited AIDS research.


title: Jimmy Somerville

text: In 1991, Somerville provided backing vocals to a track called "Why Aren't You in Love With Me?" from the album "Ripe" by Communards offshoot band Banderas. The Banderas duo, Caroline Buckley and Sally Herbert, had previously been part of Somerville's backing band. After this, he disappeared from the limelight for several years. He returned in 1995 with the album "Dare to Love", which included "Heartbeat" (a UK Top 30 hit and a No. 1 hit on the US dance chart), "Hurt So Good" and "By Your Side", though commercial success was now beginning to elude him and his contract with London Records to which he had been signed for over a decade came to an end.


title: Jimmy Somerville

text: A new single, "Dark Sky", was released in 1997 and peaked at No. 66 in the UK. In the same year he provided vocals on "The Number One Song in Heaven" for the Sparks album "Plagiarism" with production by Tony Visconti. His third album, entitled "Manage The Damage", was released in 1999 via Gut Records, but failed to chart. A companion remix album, "Root Beer", came out in 2000. His dance-orientated fourth solo album, "Home Again", was released in 2004, again not charting.


title: Jimmy Somerville

text: May 2009 saw the release of Somerville's "Suddenly Last Summer" album, which contained acoustic interpretations of other people's songs. The album was initially only available as a digital download but in May 2010 was made available in a limited edition (3,000 copies) CD/DVD in the UK. In late 2010, Somerville released a dance EP called "Bright Thing".


title: Jimmy Somerville

text: 2010's EP "Bright Thing" was the first of a series of three, with Somerville releasing "Momentum" in 2011 and "Solent" in 2012, with long-term collaborator John Winfield.


title: Jimmy Somerville

text: Somerville released a disco-inspired album called "Homage" in 2014. Singles were "Back to Me" followed by "Travesty". The emphasis in recording the album was on achieving the musical authenticity of original disco which Somerville grew up listening to. He stated: "I've finally made the disco album I always wanted to and never thought I could."


title: Jimmy Somerville

text: He has also had an acting career, appearing in Sally Potter's 1992 film of Virginia Woolf's "Orlando", in Isaac Julien's 1989 "Looking for Langston", and in an episode of the cult science fiction television series "Lexx" ("Girltown").


title: Jimmy Somerville

text: In February 2021, Somerville teamed up with producer Sally Herbert (formerly of 1990s duo Banderas and also part of The Communards' backing band) to record a cover of "Everything Must Change" by Benard Ighner as a charity record for End Youth Homelessness, a network of projects which includes Centrepoint in London and a number of other homeless charity organisations around the UK.


title: Hepatitis B

text: Hepatitis B is an infectious disease caused by the "Hepatitis B virus" (HBV) that affects the liver; it is a type of viral hepatitis. It can cause both acute and chronic infection.


title: Hepatitis B

text: Many people have no symptoms during an initial infection. For others, symptoms may appear 30 to 180 days after becoming infected and can include a rapid onset of sickness with nausea, vomiting, yellowish skin, fatigue, dark urine, and abdominal pain. Symptoms during acute infection typically last for a few weeks, though some people may feel sick for up to six months. Deaths resulting from acute stage HBV infections are rare. An HBV infection lasting longer than six months is usually considered chronic. The likelihood of developing chronic hepatitis B is higher for those who are infected with HBV at a younger age. About 90% of those infected during or shortly after birth develop chronic hepatitis B, while less than 10% of those infected after the age of five develop chronic cases. Most of those with chronic disease have no symptoms; however, cirrhosis and liver cancer eventually develop in about 25% of those with chronic HBV.


title: Hepatitis B

text: The virus is transmitted by exposure to infectious blood or body fluids. In areas where the disease is common, infection around the time of birth or from contact with other people's blood during childhood are the most frequent methods by which hepatitis B is acquired. In areas where the disease is rare, intravenous drug use and sexual intercourse are the most frequent routes of infection. Other risk factors include working in healthcare, blood transfusions, dialysis, living with an infected person, travel in countries with high infection rates, and living in an institution. Tattooing and acupuncture led to a significant number of cases in the 1980s; however, this has become less common with improved sterilization. The viruses cannot be spread by holding hands, sharing eating utensils, kissing, hugging, coughing, sneezing, or breastfeeding. The infection can be diagnosed 30 to 60 days after exposure. The diagnosis is usually confirmed by testing the blood for parts of the virus and for antibodies against the virus. It is one of five main hepatitis viruses: A, B, C, D, and E. During an initial infection, care is based on a person's symptoms. In those who develop chronic disease, antiviral medication such as tenofovir or interferon may be useful; however, these drugs are expensive. Liver transplantation is sometimes recommended for cases of cirrhosis or hepatocellular carcinoma.


title: Hepatitis B

text: Hepatitis B infection has been preventable by vaccination since 1982. As of 2022, the hepatitis B vaccine is between 98% and 100% effective in preventing infection. The vaccine is administered in several doses; after an initial dose, two or three more vaccine doses are required at a later time for full effect. The World Health Organization (WHO) recommends infants receive the vaccine within 24 hours after birth when possible. National programs have made the hepatitis B vaccine available for infants in 190 countries as of the end of 2021. To further prevent infection, the WHO recommends testing all donated blood for hepatitis B before using it for transfusion. Using antiviral prophylaxis to prevent mother-to-child transmission is also recommended, as is following safe sex practices, including the use of condoms In 2016, the WHO set a goal of eliminating viral hepatitis as a threat to global public health by 2030. Achieving this goal would require the development of therapeutic treatments to cure chronic hepatitis B, as well as preventing its transmission and using vaccines to prevent new infections.


title: Hepatitis B

text: An estimated 296 million people, or 3.8% of the global population, had chronic hepatitis B infections as of 2019. Another 1.5 million developed acute infections that year, and 820,000 deaths occurred as a result of HBV. Cirrhosis and liver cancer are responsible for most HBV-related deaths. The disease is most prevalent in Africa (affecting 7.5% of the continent’s population) and in the Western Pacific region (5.9%). Infection rates are 1.5% in Europe and 0.5% in the Americas. According to some estimates, about a third of the world's population has been infected with hepatitis B at one point in their lives. Hepatitis B was originally known as "serum hepatitis".


title: Hepatitis B

text: Acute infection with virus is associated with acute viral hepatitis, an illness that begins with general ill-health, loss of appetite, nausea, vomiting, body aches, mild fever, and dark urine, and then progresses to development of jaundice. The illness lasts for a few weeks and then gradually improves in most affected people. A few people may have a more severe form of liver disease known as fulminant hepatic failure and may die as a result. The infection may be entirely asymptomatic and may go unrecognized.


title: Hepatitis B

text: Chronic infection with virus may be asymptomatic or may be associated with chronic inflammation of the liver (chronic hepatitis), leading to cirrhosis over a period of several years. This type of infection dramatically increases the incidence of hepatocellular carcinoma (HCC; liver cancer). Across Europe, hepatitis B and C cause approximately 50% of hepatocellular carcinomas. Chronic carriers are encouraged to avoid consuming alcohol as it increases their risk for cirrhosis and liver cancer. virus has been linked to the development of membranous glomerulonephritis (MGN).


title: Hepatitis B

text: Symptoms outside of the liver are present in 1–10% of HBV-infected people and include serum-sickness–like syndrome, acute necrotizing vasculitis (polyarteritis nodosa), membranous glomerulonephritis, and papular acrodermatitis of childhood (Gianotti–Crosti syndrome). The serum-sickness–like syndrome occurs in the setting of acute , often preceding the onset of jaundice. The clinical features are fever, skin rash, and polyarteritis. The symptoms often subside shortly after the onset of jaundice but can persist throughout the duration of acute . About 30–50% of people with acute necrotizing vasculitis (polyarteritis nodosa) are HBV carriers. HBV-associated nephropathy has been described in adults but is more common in children. Membranous glomerulonephritis is the most common form. Other immune-mediated hematological disorders, such as essential mixed cryoglobulinemia and aplastic anemia have been described as part of the extrahepatic manifestations of HBV infection, but their association is not as well-defined; therefore, they probably should not be considered etiologically linked to HBV.


title: Hepatitis B

text: Transmission of virus results from exposure to infectious blood or body fluids containing blood. HBV is 50 to 100 times more infectious than human immunodeficiency virus (HIV). HBV can be transmitted through several routes of infection. In vertical transmission, HBV is passed from mother to child (MTCT) during childbirth. Without intervention, a mother who is positive for HBsAg has a 20% risk of passing the infection to her offspring at the time of birth. This risk is as high as 90% if the mother is also positive for HBeAg.


title: Hepatitis B

text: Early life horizontal transmission can occur through bites, lesions, certain sanitary habits, or other contact with secretions or saliva containing HBV. Adult horizontal transmission is known to occur through sexual contact, blood transfusions and transfusion with other human blood products, re-use of contaminated needles and syringes. Breastfeeding after proper immunoprophylaxis does not appear to contribute to mother-to-child-transmission (MTCT) of HBV.


title: Hepatitis B

text: virus (HBV) is a member of the hepadnavirus family. The virus particle (virion) consists of an outer lipid envelope and an icosahedral nucleocapsid core composed of core protein. These virions are 30–42 nm in diameter. The nucleocapsid encloses the viral DNA and a DNA polymerase that has reverse transcriptase activity. The outer envelope contains embedded proteins that are involved in viral binding of, and entry into, susceptible cells. The virus is one of the smallest enveloped animal viruses. The 42 nm virions, which are capable of infecting liver cells known as hepatocytes, are referred to as "Dane particles". In addition to the Dane particles, filamentous and spherical bodies lacking a core can be found in the serum of infected individuals. These particles are not infectious and are composed of the lipid and protein that forms part of the surface of the virion, which is called the surface antigens (HBsAg), and is produced in excess during the life cycle of the virus.


title: Hepatitis B

text: The genome of HBV is made of circular DNA, but it is unusual because the DNA is not fully double-stranded. One end of the full length strand is linked to the viral DNA polymerase. The genome is 3020–3320 nucleotides long (for the full-length strand) and 1700–2800 nucleotides long (for the short length-strand). The negative-sense (non-coding) is complementary to the viral mRNA. The viral DNA is found in the nucleus soon after infection of the cell. The partially double-stranded DNA is rendered fully double-stranded by completion of the (+) sense strand and removal of a protein molecule from the (−) sense strand and a short sequence of RNA from the (+) sense strand. Non-coding bases are removed from the ends of the (−) sense strand and the ends are rejoined. There are four known genes encoded by the genome, called C, X, P, and S. The core protein is coded for by gene C (HBcAg), and its start codon is preceded by an upstream in-frame AUG start codon from which the pre-core protein is produced. HBeAg is produced by proteolytic processing of the pre-core protein. In some rare strains of the virus known as Hepatitis B virus precore mutants, no HBeAg is present.


title: Hepatitis B

text: The DNA polymerase is encoded by gene P. Gene S is the gene that codes for the surface antigen (HBsAg). The HBsAg gene is one long open reading frame but contains three in frame "start" (ATG) codons that divide the gene into three sections, pre-S1, pre-S2, and S. Because of the multiple start codons, polypeptides of three different sizes called large (the order from surface to the inside: pre-S1, pre-S2, and S ), middle (pre-S2, S), and small (S) are produced. There is a myristyl group, which plays an important role in infection, on the amino-terminal end of the preS1 part of the large (L) protein. In addition to that, N terminus of the L protein have virus attachment and capsid binding sites. Because of that, the N termini of half of the L protein molecules are positioned outside the membrane and the other half positioned inside the membrane.


title: Hepatitis B

text: The function of the protein coded for by gene X is not fully understood but it is associated with the development of liver cancer. It stimulates genes that promote cell growth and inactivates growth regulating molecules.


title: Hepatitis B

text: The life cycle of virus is complex. is one of a few known pararetroviruses: non-retroviruses that still use reverse transcription in their replication process. The virus gains entry into the cell by binding to NTCP on the surface and being endocytosed. Because the virus multiplies via RNA made by a host enzyme, the viral genomic DNA has to be transferred to the cell nucleus by host proteins called chaperones. The partially double-stranded viral DNA is then made fully double stranded by a viral polymerase and transformed into covalently closed circular DNA (cccDNA). This cccDNA serves as a template for transcription of four viral mRNAs by host RNA polymerase. The largest mRNA, (which is longer than the viral genome), is used to make the new copies of the genome and to make the capsid core protein and the viral DNA polymerase. These four viral transcripts undergo additional processing and go on to form progeny virions that are released from the cell or returned to the nucleus and re-cycled to produce even more copies. The long mRNA is then transported back to the cytoplasm where the virion P protein (the DNA polymerase) synthesizes DNA via its reverse transcriptase activity.


title: Hepatitis B

text: The virus is divided into four major serotypes (adr, adw, ayr, ayw) based on antigenic epitopes presented on its envelope proteins, and into eight major genotypes (A–H). The genotypes have a distinct geographical distribution and are used in tracing the evolution and transmission of the virus. Differences between genotypes affect the disease severity, course and likelihood of complications, and response to treatment and possibly vaccination. There are two other genotypes I and J but they are not universally accepted as of 2015. The diversity of genotypes is not shown equally in the world. For example, A, D, and E genotypes have been seen in Africa prevalently while B and C genotypes are observed in Asia as widespread.


title: Hepatitis B

text: Genotypes differ by at least 8% of their sequence and were first reported in 1988 when six were initially described (A–F). Two further types have since been described (G and H). Most genotypes are now divided into subgenotypes with distinct properties.


title: Hepatitis B

text: virus primarily interferes with the functions of the liver by replicating in hepatocytes. A functional receptor is NTCP. There is evidence that the receptor in the closely related duck hepatitis B virus is carboxypeptidase D. The virions bind to the host cell via the preS domain of the viral surface antigen and are subsequently internalized by endocytosis. HBV-preS-specific receptors are expressed primarily on hepatocytes; however, viral DNA and proteins have also been detected in extrahepatic sites, suggesting that cellular receptors for HBV may also exist on extrahepatic cells.


title: Hepatitis B

text: During HBV infection, the host immune response causes both hepatocellular damage and viral clearance. Although the innate immune response does not play a significant role in these processes, the adaptive immune response, in particular virus-specific cytotoxic T lymphocytes(CTLs), contributes to most of the liver injury associated with HBV infection. CTLs eliminate HBV infection by killing infected cells and producing antiviral cytokines, which are then used to purge HBV from viable hepatocytes. Although liver damage is initiated and mediated by the CTLs, antigen-nonspecific inflammatory cells can worsen CTL-induced immunopathology, and platelets activated at the site of infection may facilitate the accumulation of CTLs in the liver.


title: Hepatitis B

text: The tests, called assays, for detection of virus infection involve serum or blood tests that detect either viral antigens (proteins produced by the virus) or antibodies produced by the host. Interpretation of these assays is complex.


title: Hepatitis B

text: The surface antigen (HBsAg) is most frequently used to screen for the presence of this infection. It is the first detectable viral antigen to appear during infection. However, early in an infection, this antigen may not be present and it may be undetectable later in the infection as it is being cleared by the host. The infectious virion contains an inner "core particle" enclosing viral genome. The icosahedral core particle is made of 180 or 240 copies of the core protein, alternatively known as core antigen, or HBcAg. During this 'window' in which the host remains infected but is successfully clearing the virus, IgM antibodies specific to the core antigen ("anti-HBc IgM") may be the only serological evidence of disease. Therefore, most diagnostic panels contain HBsAg and total anti-HBc (both IgM and IgG).


title: Hepatitis B

text: Shortly after the appearance of the HBsAg, another antigen called e antigen (HBeAg) will appear. Traditionally, the presence of HBeAg in a host's serum is associated with much higher rates of viral replication and enhanced infectivity; however, variants of the virus do not produce the 'e' antigen, so this rule does not always hold true. During the natural course of an infection, the HBeAg may be cleared, and antibodies to the 'e' antigen ("anti-HBe") will arise immediately afterwards. This conversion is usually associated with a dramatic decline in viral replication.


title: Hepatitis B

text: If the host is able to clear the infection, eventually the HBsAg will become undetectable and will be followed by IgG antibodies to the surface antigen and core antigen ("anti-HBs" and "anti HBc IgG"). The time between the removal of the HBsAg and the appearance of anti-HBs is called the window period. A person negative for HBsAg but positive for anti-HBs either has cleared an infection or has been vaccinated previously.


title: Hepatitis B

text: Individuals who remain HBsAg positive for at least six months are considered to be carriers. Carriers of the virus may have chronic hepatitis B, which would be reflected by elevated serum alanine aminotransferase (ALT) levels and inflammation of the liver, if they are in the immune clearance phase of chronic infection. Carriers who have seroconverted to HBeAg negative status, in particular those who acquired the infection as adults, have very little viral multiplication and hence may be at little risk of long-term complications or of transmitting infection to others. However, it is possible for individuals to enter an "immune escape" with HBeAg-negative hepatitis.


title: Hepatitis B

text: PCR tests have been developed to detect and measure the amount of HBV DNA, called the viral load, in clinical specimens. These tests are used to assess a person's infection status and to monitor treatment. Individuals with high viral loads, characteristically have ground glass hepatocytes on biopsy.


title: Hepatitis B

text: Vaccines for the prevention of hepatitis B have been routinely recommended for babies since 1991 in the United States. The first dose is generally recommended within a day of birth. The hepatitis B vaccine was the first vaccine capable of preventing cancer, specifically liver cancer.