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Hatter's Castle

Hatter's Castle (1931) is the first novel of author A. J. Cronin. The story is set in 1879, in the fictional town of Levenford, on the Firth of Clyde. The plot revolves around many characters and has many subplots, all of which relate to the life of the hatter, James Brodie, whose narcissism and cruelty gradually destroy his family and life. The book was made into a successful film in 1942 starring Robert Newton, Deborah Kerr, and James Mason.

Characters
The main characters are James Brodie (the hatter and tyrannical patriarch of the Brodie family), Mary Brodie (James's elder daughter, also one of the central characters, appearing throughout the first and last section of the novel), Matthew Brodie (James's only son and oldest child in the family who also plays a significant role in the novel), Nessie Brodie (James's younger daughter and favourite, who remains one of the background characters until the end of the story), Mrs. Brodie (James's fragile wife who is never treated as anything more than a servant by her husband), Grandma Brodie (James's mother who lives with the Brodie family), Dennis Foyle (A young Irishman who has a relationship with Mary), Nancy (James's mistress) and Dr. Renwick (a character who becomes more involved in the Brodies' family life towards the end of the novel).

Plot summary
The book is in three sections.

Part 1
The novel begins with some insight into the life of the Brodie household, where James Brodie seems to have everyone under his thumb. The main event that triggers the events in the novel is Mary Brodie's relationship with her first love, Dennis. Early in the story, Mary, who has occasionally met Dennis at the library, is invited by him to go to the fair in the town. She sneaks out without her family's knowledge and not only goes to the fair, but later on that night kisses and eventually makes love to Dennis, which we later learn, results in pregnancy.

This event of her unwanted pregnancy is the main plot in the first third of the novel, titled "Section One". We realise that Mary is pregnant, and when she is six months pregnant she makes a plan with Dennis to elope. Even though Mary was only seventeen, there would have been no legal problem with her marriage since the English law which, until 1970, generally required people under twenty-one to have parental consent to marry, did not apply in Scotland. But three days before Dennis is due to whisk Mary away, there is a massive storm, and she begins to go into labour. Mrs. Brodie stumbles into Mary's room and begins to scream at the fact that her daughter is with child, and calls James himself to sort it out. After being kicked in the stomach repeatedly by her father and thrown out on her face into the pouring rain (whilst in labour), she tries to reach safety. Mary nearly drowns in a river before finding a barn where she gives birth to her premature child, which dies. Dennis, who was, travelling on a train to rescue Mary, is killed when the train derails and plunges into the River Tay below, a retelling of the actual Tay Bridge disaster of 1879.

Part 2
In the second part of the book, James Brodie's business as a hatter is destroyed. A rival company moves next door and attracts all his customers. Part of this is due to Brodie's pride, as the customers are driven away by his delusions of superiority. As his profits decrease, so does the weekly salary, so Mamma is left to deal with making the most of what little they have left for the family. Her illness, cancer of the womb, and the chronic stress of living with James Brodie hasten her death. After her death, Brodie's mistress, Nancy, moves in. Later she goes off abroad with Brodie's son Matt, and Brodie is left with only his younger daughter, Nessie, and his aged mother, Grandma Brodie.

Part 3
In the third part of the book, Brodie forces Nessie to study hard so as to win the "Latta", a valuable bursarship. He wants this not so much to provide a good future for his daughter, as to show that she is better than his rival's son, who is also entered for it. Under his threats and the dreadful fear of failure, she labours on with it, making herself mentally and physically ill. Nessie secretly writes to Mary asking her to come back, so she will have her company and comfort. Under pretext of coming to help with housework, Mary writes to her father, who initially refuses her return. After discovering that Nancy has deserted him, he writes again permitting Mary to come back, so she does.

Nessie obtains notice of the Latta result before her father sees it. Finding that her rival has won it and fearing her father, she sends Mary out to the chemist on the pretext of getting some medicine, then dresses up and hangs herself.

The story concludes with Dr. Renwick, who has been seeing Mary, taking her away with him to marry her.

The novel in other countries

 * In Russian "Hatter's Castle" was first published in 1955 under the name "Brodie's Castle", which has not changed since then.

title: Hatter's Castle


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Parrotbill

The parrotbills are a family, Paradoxornithidae, of passerine birds that are primarily native to East, Southeast and South Asia, with a single species in western North America, though feral populations exist elsewhere. They are generally small birds that inhabit reedbeds, forests and similar habitats. The traditional parrotbills feed mainly on seeds, e.g. of grasses, to which their robust bill, as the name implies, is well-adapted. Members of the family are usually non-migratory.

The bearded reedling or "bearded tit", a Eurasian species formerly placed here, is more insectivorous by comparison, especially in summer. It also strikingly differs in morphology, such as its finer bill, and has again been moved to the monotypic family Panuridae. Conversely, a number of other mostly insectivorous species that traditionally were placed in Timaliidae (Old World babblers), for example the fulvettas and fire-tailed myzornis, along with the wrentit (a species with a conflicting taxonomic history), have been moved into Paradoxornithidae. DNA sequence data supports this.

Their general habitus and acrobatic habits resemble birds like the long-tailed tits. Together with these and others they were at some time placed in the titmouse family Paridae. Later studies found no justification to presume a close relationship between all these birds, and consequently the parrotbills and bearded reedling were removed from the tits and chickadees and placed into a distinct family. As names like Paradoxornis paradoxus – "puzzling, paradox bird" – suggest, their true relationships were very unclear, although by the latter 20th century they were generally seen as close to Timaliidae (Old World babblers) and Sylviidae (Old World warblers).

Taxonomy
Since 1990 (Sibley & Ahlquist 1990), molecular data has been added to aid the efforts of discovering the parrotbills' true relationships. As Paradoxornis species are generally elusive and in many cases little-known birds, usually specimens of the bearded reedling which are far more easy to procure were used for the analyses. Often, the entire group was entirely left out of analyses, being small and seemingly insignificant in the large pattern of bird evolution (e.g. Barker et al. 2002, 2004). The bearded reedling tended to appear close to larks in phylogenies based on e.g. DNA-DNA hybridization (Sibley & Ahlquist 1990), or on mtDNA cytochrome b and nDNA c-myc exon 3, RAG-1 and myoglobin intron 2 sequence data (Ericson & Johansson 2003). Placement in a superfamily Sylvioidea which contained birds such as Sylviidae, Timaliidae and long-tailed tits – but not Paridae – was confirmed.

Cibois (2003a) analyzed mtDNA cytochrome b and 12S/16S rRNA sequences of some Sylvioidea, among them several species of Paradoxornis but not the bearded reedling. These formed a robust clade closer to the Sylvia typical warblers and some presumed "Old World babblers" such as Chrysomma sinense than to other birds. The puzzle was finally resolved by Alström et al. (2006), who studied mtDNA cytochrome b and nDNA myoglobin intron 2 sequences of a wider range of Sylvioidea: The bearded reedling was not a parrotbill at all, but forms a distinct lineage on its own, the relationships of which are not entirely resolved at present. The parrotbills' presence in the clade containing Sylvia, on the other hand, necessitates that the Paradoxornithidae are placed in synonymy of the Sylviidae. Cibois (2003b) even suggested that these themselves were to be merged with the remaining Timaliidae and the latter name to be adopted. This has hitherto not been followed and researchers remain equivocal as many taxa in Sylviidae and Timaliidae remain to be tested for their relationships. In any case, it is most likely that the typical warbler-parrotbill group is monophyletic and therefore agrees with the modern requirements for a taxon. Hence, whether to keep or to synonymize it is entirely a matter of philosophy, as the scientific facts would agree with either approach.

The interesting conclusion from an evolutionary point of view is that the morphologically both internally homogenous and compared to each other highly dissimilar typical warblers and parrotbills form the two extremes in the divergent evolution of the Sylviidae. This is underscored by looking at the closest living relatives of the parrotbills in the rearranged Sylviidae: The genus Chrysomma are non-specialized species altogether intermediate in habitus, habitat and habits between the typical warblers and the parrotbills. Presumably, the ancestral sylviids looked much like these birds. How dramatic the evolutionary changes wrought upon the parrotbills in their adaptation to feeding on grass caryopses and similar seeds were can be seen by comparing them with the typical fulvettas, which were formerly considered Timaliidae and united with the alcippes (Pasquet 2006). These look somewhat like drab fairy-wrens and have none of the parrotbills' adaptations to food and habitat. Yet it appears that the typical fulvettas' and parrotbills' common ancestor evolved into at least two parrotbill lineages independently (Cibois 2003a) & (Yeung et al. 2006). Only the wrentit, the only American sylviid, resembles the parrotbills much in habitus, though not in color pattern, and of course, as an insectivore, neither in bill shape.

The phylogenetic relationships between the Paradoxornithidae and other families was determined in a molecular phylogenetic study by Tianlong Cai and collaborators that was published in 2019. It is shown in the cladogram below:.

The cladogram below shows the relationships between the genera in the family Paradoxornithidae. It is based on the results of the molecular phylogenetic study by Tianlong Cai and collaborators and the generic divisions adopted by Frank Gill, Pamela Rasmussen and David Donsker in the list of birds maintained on behalf of the International Ornithological Committee.

Species
There are 38 species of parrotbills and allies distributed among 9 genera. This list is presented according to the IOC taxonomic sequence and can also be sorted alphabetically by common name and binomial.

Egg recognition
Parrotbill egg recognition is the ability of the parrotbill to distinguish its own eggs against the eggs of a brood parasite. Without their own eggs in the nest, parrotbills are not able to identify whether their nest has been intruded by the eggs of a brood parasite. Because the colour and number of eggs may vary, there are varying outcomes to whether parrotbills will reject or accept the eggs whether it be their own or if they are acting host for another species. Cognitive mechanisms including recognition by discordance and template-based recognition are hypothesized to be the manner in which a host's eggs are identified. The common cuckoo lays its eggs in the nests of parrotbills and the two have co-evolved together over time to promote the reproductive success of both species. The common cuckoo is an example of an avian brood parasite that reduces the energy cost of caring for its eggs by placing them in the parrotbill's nest.

Depending on the parrotbill species, the eggs will either be maculate with spots or marks or immaculate, meaning without spots or marks. The cuckoo is also able to lay eggs that replicate the ones of its hosts in a means to have its eggs accepted by the host. Whether the parasitic eggs are accepted by the host is based on two hypothetical cognitive mechanisms. True or template-based recognition predicts that by learning or by instinct, the parrotbill would be able to reject the brood parasite eggs. If learned, the parrotbill would imprint on its own eggs and would be able to use it as a template to compare to foreign eggs. Recognition by discordancy is the least favoured hypothesis among scientists of the two mechanisms, but describes the action of rejecting the eggs which appear to be the minority whether it is their own eggs or the parasite's eggs; it does not require learning or instinctive behaviour. Some studies have predicted discordancy is favoured as certain species demonstrate the behaviour at all life stages; if the behaviour is demonstrated at a young age, it may not be an example of learning as the time for learning could be too short.

One parrotbill species that has been studied is the ashy-throated parrotbill (Paradoxornis alphonsianus) and demonstrated the use of both mechanisms relaying there may not be one "universal method". The eggs of the ashy-throated parrotbill are immaculate and polymorphic in which multiple phenotypic colours in that species is produced; its eggs are placed in competition with the eggs of the common cuckoo (Cuculus canorus). Typically, the female cuckoo lays its eggs in the nest of the parrotbill after taking out one of the host's eggs. The immaculate colours in this species are blue, pale blue and white, but only one colour is present at a time and the female produces only one colour over its lifetime.

If parrotbills do not have their own eggs within the nest, it has been observed they accept the eggs of the avian brood parasite, as the "cue" of the presence of their own eggs has not been established. Time is also important for both male and female parrotbills as it can be the factor in whether the parrotbill will recognize parasitic eggs. For females, it is crucial they learn the egg phenotype as the eggs are being laid, but if this learning is not immediate, parasitic eggs can be accepted and imprinted. Males learn their respective egg phenotype once the clutch has reached completion.

In some species, male parrotbills also incubate eggs, and they are predicted to follow discordancy recognition for this behaviour as the males may encounter multiple egg types with different mates over time. This could lead to rejection of their own eggs based on previous knowledge of egg colour. A possible exception to this idea is if the host parrotbill produces eggs that are monomorphic. If male parrotbills do not imprint on their own eggs, they increase the probability of production of varied phenotypes of egg colour and patterns within the population.

If a host species is new to an area, it is suspected cuckoo parasitism will be favoured as recognition of parasitic eggs has not yet occurred. Over time, the two species co-evolve with the parrotbill first utilizing one of the hypothesized cognitive mechanisms in order to recognize parasitic eggs. In order to compensate for this new behaviour in parrotbills, the parasite produces eggs that are similar to those of the host and leads to the evolution of polymorphisms over time for both species.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Parrotbill


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Sear

Sear may refer to:

People

 * Cliff Sear (1936–2000), a Welsh footballer
 * Helen Sear (born 1955), a Welsh photographic artist
 * Morey Leonard Sear (1929–2004), a United States federal judge
 * Tammy Sear (born 1977), a British former competitive figure skater
 * Walter Sear (1930–2010), an American recording engineer and musician

Places

 * Sahar Elevated Access Road, an elevated express access road in Mumbai, India

Other uses

 * Sear (firearm), part of the trigger mechanism on a firearm
 * Sear, to cook by searing, a cooking technique which quickly cooks the exterior of a food item
 * Sear, a client for the WorldForge MMORPG framework
 * Seir (demon), a Prince of Hell; also spelled Sear
 * SEAr, the Hughes–Ingold symbol for the electrophilic aromatic substitution reaction
 * antiquated, turn of the century Scandinavian men's first name. Pronounced "Say-er"

title: Sear


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Hatter (disambiguation)

A hatter is a person engaged in hatmaking.

Hatter(s) may also refer to:

People

 * Clyde Hatter (1908–1937), American baseball player
 * Hamilton Hatter (1856–1942), African American professor
 * Maddelynn Hatter, American drag queen
 * Steve Hatter (born 1958), English footballer
 * Terry J. Hatter Jr. (born 1933), American judge
 * Tony Hatter, British automobile designer
 * Hatter, a demonym of residents of Medicine Hat, Canada

Sports

 * Danbury Hatters, an American baseball team (1887–1914)
 * Madison Hatters, an American baseball team
 * Stetson Hatters, Stetson University's athletics teams
 * Luton Town F.C. or the Hatters, an English football team
 * Stockport County F.C. or the Hatters, an English football team

Other uses

 * Hatter (Alice's Adventures in Wonderland), a character in Lewis Carroll's stories
 * Hatter Fox, a character in Marilyn Harris's stories
 * Háttér Society, an LGBTQI NGO in Hungary

title: Hatter (disambiguation)


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Tidal

Tidal is the adjectival form of tide.

Tidal may also refer to:
 * Tidal (album), a 1996 album by Fiona Apple
 * Tidal (king), a king involved in the Battle of the Vale of Siddim
 * TidalCycles, a live coding environment for music
 * Tidal (service), a music streaming service
 * Tidal: Occupy Theory, Occupy Strategy, a magazine associated with the Occupy Wall Street movement

title: Tidal


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New York City Police Department

The New York City Police Department (NYPD), officially the City of New York Police Department, is the primary law enforcement agency within New York City. Established on May 23, 1845, the NYPD is the largest, and one of the oldest, municipal police departments in the United States.

The NYPD is headquartered at 1 Police Plaza, located on Park Row in Lower Manhattan near City Hall. The NYPD's regulations are compiled in title 38 of the New York City Rules. The NYC Transit Police and NYC Housing Authority Police Department were fully integrated into the NYPD in 1995. Dedicated units of the NYPD include the Emergency Service Unit, K-9, harbor patrol, highway patrol, air support, bomb squad, counterterrorism, criminal intelligence, anti-organized crime, narcotics, mounted patrol, public transportation, and public housing units.

The NYPD employs over 40,000 people, including more than 30,000 uniformed officers as of September 2023. According to the official CompStat database, the NYPD responded to nearly 500,000 reports of crime and made over 200,000 arrests during 2019. In 2020, it had a budget of US$6 billion. However, the NYPD's actual spending often exceeds its budget.

The NYPD has a history of police brutality, corruption, and misconduct, which critics argue persists into the present day.

Due to its high-profile location in New York City, the largest city and media center in the U.S., fictionalized versions of the NYPD and its officers have frequently been portrayed in novels, radio, television, motion pictures, and video games.

History
The Municipal Police were established in 1845, replacing an old night watch system. Mayor William Havemeyer shepherded the NYPD together.

The NYPD appointed its first Black officer in 1911 and the first female officer in 1918.

During Richard Enright's tenure as commissioner, the country's first Shomrim Society, a fraternal organization of Jewish police officers, was founded in the NYPD in 1924. At the time, NYPD had 700 Jewish officers on the force.

In 1961, highly decorated NYPD officer Mario Biaggi, later a US Congressman, became the first police officer in New York State to be made a member of the National Police Officers Hall of Fame.

In the mid-1980s, the NYPD began to police street-level drug markets much more intensively, leading to a sharp increase in incarceration.

In 1992, Mayor David Dinkins created an independent Civilian Complaint Review Board for the NYPD. In response to this, some NYPD officers violently protested and rioted. They blocked traffic on the Brooklyn Bridge, demonstrated at City Hall and shouted racial epithets. The protests were sponsored by the NYPD union.

In 1994 the NYPD developed the CompStat computer system for tracking crime geographically, which is now in use by other police departments in the United States and Canada. Research is mixed on whether CompStat had an impact on crime rates.

The New York City Transit Police and the New York City Housing Authority Police Department were merged into the NYPD in 1995.

In 2021, the NYPD ceased enforcement of marijuana crimes other than driving under the influence.

Organization and structure
The department is administered and governed by the police commissioner, who is appointed by the mayor. Technically, the Commissioner serves a five-year term; as a practical matter, they serve at the mayor's pleasure. The commissioner in turn appoints the first deputy commissioner, numerous deputy commissioners, and the Chief of Department (The most senior uniformed officer). By default, the commissioner and their subordinate deputies are civilians under an oath of office and are not sworn officers. However, a commissioner who comes up from the sworn ranks retains the status and statutory powers of a police officer while serving as commissioner. This affects their police pensions, and their ability to carry a firearm without a pistol permit. Some police commissioners carry a personal firearm, but they also have a full-time security detail.

Commissioners and deputy commissioners are administrators who specialize in areas of great importance to the Department, such as counterterrorism, support services, public information, legal matters, intelligence, and information technology. However, as civilian administrators, deputy commissioners are prohibited from taking operational control of a police situation (the commissioner and the first deputy commissioner may take control of these situations, however). Within the rank structure, there are also designations, known as "grades", that connote differences in duties, experience, and pay. However, supervisory functions are generally reserved for the rank of sergeant and above.

Office of the Chief of Department
The Chief of Department serves as the senior sworn member of the NYPD. Jeffrey Maddrey, a longtime NYPD veteran, is the 43rd individual to hold the post. which before 1987 was known as the chief of operations and before that as chief inspector.

Bureaus
The department is divided into 20 bureaus, which are typically commanded by a uniformed bureau chief (such as the chief of patrol and the chief of housing) or a civilian deputy commissioner (such as the Deputy Commissioner of Information Technology). The bureaus fit under four umbrellas: Patrol, Transit & Housing, Investigative, and Administrative. Bureaus are often subdivided into smaller divisions and units. All deputy commissioners report directly to the Commissioner and bureau chiefs report to the Commissioner through the Chief of Department.

Rank structure
Officers graduate from the Police Academy after five and a half to six months (or sometimes more) of training in various academic, physical, and tactical fields. For the first 18 months of their careers, they are designated as "Probationary Police Officers", or more informally, "rookies".

There are three career "tracks" in the NYPD: supervisory, investigative, and specialist. The supervisory track consists of nine ranks; promotion to the ranks of sergeant, lieutenant, and captain are made via competitive civil service examinations. After reaching the rank of captain, promotion to the ranks of deputy inspector, inspector, deputy chief, assistant chief, (bureau) chief, and chief of department is at the discretion of the police commissioner. Promotion from the rank of police officer to detective is discretionary by the police commissioner or required by law when the officer has performed eighteen months or more of investigative duty.

Badges
Badges in the New York City Police Department are referred to as "shields" (the traditional term), though not all badge designs are strictly shield-shaped. Some officers have used "Pottsy" badges, "dupes", or duplicate badges, as officers are punished for losing their shield by also losing up to ten days' pay.

Every rank has a different badge design (except "police officer" and "probationary police officer") and, upon change in rank, officers receive a new badge. Lower-ranked police officers are identified by their shield numbers, and tax registry numbers. Lieutenants and above do not have shield numbers and are identified by tax registry numbers. All sworn members of the NYPD have their ID card photos taken against a red background. Civilian employees of the NYPD have their ID card photos taken against a blue background, signifying that they are not commissioned to carry a firearm. All ID cards have an expiration date. Although the First Deputy Commissioner and Chief of Department share the same insignia (four stars), the First Deputy Commissioner outranks the Chief of Department. The Deputy Commissioners Bureau Chiefs/Bureau Chief Chaplains and Chief Surgeon have three stars.

Department composition
As of October 2023, the NYPD's current authorized uniformed strength is 33,536. There are also 19,454 civilian employees, including approximately 4,500 auxiliary police officers, 5,500 school safety agents, and 3,500 traffic enforcement agents currently employed by the department. The Police Benevolent Association of the City of New York (NYC PBA), the largest municipal police union in the United States, represents over 50,000 active and retired NYC police officers.

Of the entire 33,536-member police force in 2023: 47% are white and 53% are members of minority groups.

Of 21,603 officers on patrol: Of 5,164 detectives: Of 4,376 sergeants: Of 1,635 lieutenants: Of 360 captains: Of 101 police chiefs:
 * 43% are non-Hispanic white
 * 57% are black, Latino (of any race), or Asian or Asian-American.
 * 52% are non-Hispanic white
 * 48% are black, Latino (of any race), or Asian or Asian-American.
 * 52% are non-Hispanic white
 * 48% are black, Latino (of any race), or Asian or Asian-American.
 * 59% are non-Hispanic white
 * 41% are black, Latino (of any race), or Asian or Asian-American.
 * 62% are non-Hispanic white
 * 38% are black, Latino (of any race), or Asian or Asian-American.
 * 57% are non-Hispanic white and
 * 43% are non-white.

Women in the NYPD
On January 1, 2022, Keechant Sewell became the first woman to serve as Commissioner of the NYPD. Juanita N. Holmes, appointed Chief of the Patrol Bureau in 2020, was the first black woman to hold this command and at the time of her appointment, was the highest-ranked uniformed woman in the NYPD. On June 12, 2023, Sewell announced that she was stepping down as commissioner. No reason was given for her departure.

Place of residence
As a rule, NYPD officers can reside in New York City as well as Westchester, Rockland, Orange, Putnam, Suffolk and Nassau counties and approximately half of them live outside the city (51% in 2020, up from 42% in 2016). Legislation has been introduced to require newly hired officers to reside in New York City.

Fallen officers
The NYPD has lost 932 officers in the line of duty since 1849. This figure includes officers from agencies that were later absorbed by or became a part of the modern NYPD, in addition to the NYPD itself. This number also includes 28 officers killed on and off duty by gunfire of other officers on duty. 286 officers have been shot and killed by a criminal. The NYPD lost 23 officers in the September 11, 2001 attacks, not including another 247 who later died of 9/11-related illnesses. The NYPD has more line-of-duty deaths than any other American law enforcement agency.

Services
The NYPD has a broad array of specialized services, including the Emergency Service Unit, K9, harbor patrol, air support, bomb squad, counter-terrorism, criminal intelligence, anti-gang, anti-organized crime, narcotics, public transportation, and public housing units. The NYPD Intelligence Division & Counter-Terrorism Bureau has officers stationed in eleven cities internationally.

In 2019 the NYPD responded to 482,337 reports of crime and made 214,617 arrests. There were 95,606 major felonies reported in 2019, compared to over half a million per year when crime in New York City peaked during the crack epidemic of the 1980s and 1990s.

Public opinion
The Quinnipiac University Polling Institute has been regularly measuring public opinion of the NYPD since 1997 when just under 50% of the public approved of the job the NYPD was doing. Approval peaked at 78% in 2002 following the World Trade Center terrorist attacks in September 2001, and has ranged between 52 and 72% since.

Approval varies by race/ethnicity, with black and Hispanic respondents consistently less likely to say they approve of the job the NYPD is doing than whites.

In 2017, the Quinnipiac poll found that New York City voters approve of the way NYPD, in general, does its job by a margin of 67–25%. Approval was 79–15 percent among white voters, 52–37 percent among black voters, and 73–24 percent among Hispanic voters. 86% of voters said crime is a serious problem, 71% said police brutality is a serious problem and 61% said police corruption is a serious problem.

A 2020 poll commissioned by Manhattan Institute for Policy Research reported that the public approved of the NYPD 53% to 40% against, again with strong racial differences: 59% of whites and Asians approved, as did 51% of Hispanics, whereas 51% of black residents disapproved.

Corruption and misconduct
The NYPD has a history of police brutality, misconduct, and corruption, as well as discrimination on the basis of race, religion and sexuality. Critics, including from within the NYPD, have accused the NYPD of manipulating crime statistics. In 2009, NYPD officer Adrian Schoolcraft was arrested, abducted by his fellow officers and involuntarily admitted to a psychiatric hospital after he provided evidence of manipulation of crime statistics (intentional under reporting of crimes) and intentional wrongful arrests (to meet arrest quotas). He filed a federal suit against the department, which the city settled before trial in 2015, also giving him back pay for the period when he was suspended.

The Knapp Commission found in 1970 that the NYPD had systematic corruption problems.

The Civilian Complaint Review Board is an all-civilian, 13-member panel tasked with investigating misconduct or lesser abuse accusations against NYPD officers, including use of excessive force, abuse of authority, discourtesy, and offensive language. Complaints against officers may be filed online, by mail, by phone, or in person at any NYPD station. On June 8, 2020, both houses of the New York state assembly passed the Eric Garner Anti-Chokehold Act, which provides that any police officer in the state of New York who injures or kills somebody through the use of "a chokehold or similar restraint" can be charged with a class C felony, punishable by up to 15 years in prison. New York Governor Andrew Cuomo signed the police reforms into law on June 12, 2020, which he described as "long overdue".

In 2020 during the early part of the COVID-19 pandemic, many NYPD officers refused to wear face masks while policing protests related to racial injustice, contrary to the recommendations of health experts and authorities. During the George Floyd protests, The New York Times reported that more than 60 videos showed NYPD police attacking protesters, many of whom were attacked without cause. Included in these attacks were the 'kettling' of protesters, an officer removing the mask of a protester and pepper spraying him, and an incident where police vehicles were driven into a crowd. An investigation by New York City's Department of Investigation concluded that the NYPD had exercised excessive force during the George Floyd protests.

The NYPD has been persistently criticized by safe streets advocates for endangering cyclists by parking their vehicles in bike lanes,  and for misapplying the law when ticketing cyclists riding outside blocked bike lanes.

According to a 2021 FiveThirtyEight analysis, New York City spent at least an average of US$170 million annually in settlements related to police misconduct over ten years.

Technology
In the 1990s the department developed a CompStat system of management which has also since been established in other cities. The NYPD has extensive crime scene investigation and laboratory resources, as well as units that assist with computer crime investigations. In 2005, the NYPD established a "Real Time Crime Center" to assist in investigations; This is essentially a searchable database that pulls information from departmental records, including traffic tickets, court summonses, and previous complaints to reports, as well as arrest reports. The database contains files to identify individuals based on tattoos, body marks, teeth, and skin conditions, based on police records.

NYPD also maintains the Domain Awareness System, a network that provides information and analytics to police, drawn from a variety of sources, including a network of 9,000 publicly and privately owned surveillance cameras, license plate readers, ShotSpotter data, NYPD databases and radiation and chemical sensors. The Domain Awareness System of surveillance was developed as part of Lower Manhattan Security Initiative in a partnership between the NYPD and Microsoft. It allows the NYPD to track surveillance targets and gain detailed information about them. It also has access to data from at least 2 billion license plate readings, 100 million summonses, 54 million 911 calls, 15 million complaints, 12 million detective reports, 11 million arrests, and 2 million warrants. The data from the 9,000 CCTV cameras is kept for 30 days. Text records are searchable. The system is connected to 9,000 video cameras around New York City.

In 2020, the NYPD deployed a robotic dog, known as Digidog, manufactured by Boston Dynamics. The robotic dog has cameras which send back real-time footage along with lights and two-way communication, and it is able to navigate on its own using artificial intelligence. Reaction by locals to Digidog was mixed. Deployment of Digidog led to condemnation from the Surveillance Technology Oversight Project and the American Civil Liberties Union due to privacy concerns. In response to its deployment, a city council member has proposed a law banning armed robots; this would not apply to Digidog as Digidog is not armed and Boston Dynamics prohibits arming its robots. On April 24, 2021, U.S. Representative Ritchie Torres proposed new federal legislation requiring police departments receiving federal funds to report use of surveillance technology to the Department of Homeland Security and Congress. The NYPD states that the robot is meant for hostage, terrorism, bomb threat, and hazardous material situations, and that it was properly disclosed to the public under current law. Following continued pushback against Digidog, including opposition to the system's $94,000 price tag, the NYPD announced on April 28, 2021, that its lease would be terminated. In April 2023, Mayor Eric Adams announced the revival of the Digidog program in a reversal of his predecessor Bill de Blasio, saying "Digidog is out of the pound." Two robots were purchased at that time for a total of $750,000 using funds from asset forfeiture.

On duty
New NYPD officers are allowed to choose from one of two 9mm service pistols: the Glock 17 Gen4 and Glock 19 Gen4. All duty handguns were previously modified to a 12-pound (53 N) NY-2 trigger pull, though recruits were being issued handguns with a lighter trigger pull as of 2021.

The Smith & Wesson 5946 semi-automatic 9mm with a double action only (DAO) trigger, was issued to recruits in the past; however, the pistol has been discontinued. While it is no longer an option for new hires, officers who were issued the weapon may continue to use it.

Shotgun-certified officers were authorized to carry Ithaca 37 shotguns, which are being phased out in favor of the newer Mossberg 590. Officers and detectives belonging to the NYPD's Emergency Service Unit, Counter-terrorism Bureau and Strategic Response Group are armed with a range of select-fire weapons and long guns, such as the Colt M4A1 carbine and similar-pattern Colt AR-15 rifles, Heckler & Koch MP5 submachine gun, and the Remington Model 700 bolt-action rifle. NYPD ESU Officers also use the Ruger Mini 14 556 rifle.

Discontinued from service
From 1926 until 1986 the standard weapons of the department were the Smith & Wesson Model 10 and the Colt Official Police .38 Special revolvers with four-inch barrels. Female officers had the option to choose to carry a three-inch barrel revolver instead of the normal four-inch model due to its lighter weight. Before 1994, the standard weapon of the NYPD was the Smith & Wesson Model 64 DAO, a .38 Special revolver with a three- or four-inch barrel, and the Ruger Police Service-Six with a four-inch barrel. This type of revolver was called the Model NY-1 by the department. After the switch in 1994 to semi-automatic pistols, officers who privately purchased revolvers before January 1, 1994, were allowed to use them for duty use until August 31, 2018. They were grandfathered in as approved off-duty guns.

Before the issuing of the 9mm semi-automatic pistol NYPD detectives and plainclothes officers often carried the Colt Detective Special and/or the Smith & Wesson Model 36 "Chief's Special" .38 Special caliber snub-nosed (two-inch) barrel revolvers for their ease of concealment while dressed in civilian clothes.

The Kahr K9 9mm pistol was an approved off-duty/backup weapon from 1998 to 2011. It was pulled from service because it could not be modified to a 12-pound trigger pull.

Affiliations
The NYPD is affiliated with the New York City Police Foundation and the New York City Police Museum. It also runs a Youth Police academy to provide a positive interaction with police officers and to educate young people about the challenges and responsibilities of police work. The NYPD additionally sponsors a Law Enforcement Explorer Program through the Scouting Program (formerly the Boy Scouts of America). The department also operates the Citizens Police Academy, which educates the public on basic law and policing procedures.

title: New York City Police Department


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New World barbet

The New World barbets are a family, Capitonidae, of 15 birds in the order Piciformes, which inhabit humid forests in Central and South America. They are closely related to the toucans.

The New World barbets are plump birds, with short necks and large heads. They get their name from the bristles that fringe their heavy bills. Most species are brightly coloured and live in tropical forest.

These barbets are mostly arboreal birds, which nest in tree holes dug by breeding pairs, laying two to four eggs. They eat fruit and insects. These birds do not migrate.

Taxonomy
Fossil New World barbets have been found dating from the Miocene in Florida. The closest relatives of the barbets are the toucans, and these two families are also closely related to the honeyguides and woodpeckers (with which they form the order Piciformes).

Formerly, the barbets have been treated as one family. This has turned out to be paraphyletic, though, with regard to toucans; thus, only the New World true barbets are retained in the Capitonidae. The African barbets (Lybiidae) and the Asian barbets (Megalaimidae), as well as the two toucan-barbets from the Americas (Semnornithidae) are currently split from this family. Alternatively, the toucans, which evolved from a common ancestor shared with the American barbets, might be included in the traditional all-encompassing barbet family. As they have evolved characteristics that are unique to themselves, they are usually treated separately, thus the barbets are split up according to the four lineages.

The phylogenetic relationship between the New World barbets and the eight other families in the order Piciformes is shown in the cladogram below. The number of species in each family is taken from the list maintained by Frank Gill, Pamela C. Rasmussen and David Donsker on behalf of the International Ornithological Committee (IOC).

Fossils

 * 'Genus Capitonides'' (Early – Middle Miocene of Europe) (fossil)
 * †Capitonides europeus

Ecology
While most New World barbet species inhabit lowland forest, some range into montane and temperate forests, as well. Most are restricted to habitats containing trees with dead wood, which are used for nesting.

The diet of barbets is mixed, with fruit being the dominant part. Small prey items are also taken, especially when nesting. Barbets are capable of shifting their diet quickly in the face of changing food availability. Numerous species of fruiting trees and bushes are visited; an individual barbet may feed on as many as 60 different species in its range. They also visit plantations and take cultivated fruit and vegetables. Fruit is eaten whole, and indigestible material such as seed pits is regurgitated later (often before singing). Regurgitation does not usually happen in the nest (as happens with toucans). Like their relatives, New World barbets are thought to be important agents in seed dispersal in tropical forests.

As well as taking fruit, they also take arthropod prey, gleaned from the branches and trunks of trees. A wide range of insects is taken, including ants, beetles, and moths. Scorpions and centipedes are also taken, and a few species take small vertebrates such as frogs.

Relationship with humans
New World barbets have little direct impact on humans. The loss of forest can have a deleterious effect on barbet species dependent on old growth, to the benefit of species that favor more disturbed or open habitat.

Three species of New World barbets are listed as threatened by the IUCN: The white-mantled barbet of Colombia is listed as endangered and the five-coloured barbet as vulnerable, the two having a relatively small range threatened by deforestation for the timber industry and to create space for agriculture (including coca and marijuana) and livestock, and mining. The quite recently discovered scarlet-banded barbet of Peru is considered vulnerable due to its small population size (estimated at under 1000 birds), although its remote habitat is not immediately threatened.

title: New World barbet


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User:Erichsu

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title: User:Erichsu


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Talk:Pipes and filters

That's a really contrived example. I'm putting in one that is more useful. Karada

Duplication
There is much duplication between this page, pipeline (unix), and filter (Unix). Perhaps this page and pipeline (unix) should be merged into pipeline (software)? Jorge Stolfi 01:45, 3 Dec 2004 (UTC)

title: Talk:Pipes and filters


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Commuting

Commuting is periodically recurring travel between a place of residence and place of work or study, where the traveler, referred to as a commuter, leaves the boundary of their home community. By extension, it can sometimes be any regular or often repeated travel between locations, even when not work-related. The modes of travel, time taken and distance traveled in commuting varies widely across the globe. Most people in least-developed countries continue to walk to work. The cheapest method of commuting after walking is usually by bicycle, so this is common in low-income countries but is also increasingly practised by people in wealthier countries for environmental and health reasons. In middle-income countries, motorcycle commuting is very common.

The next technology adopted as countries develop is more dependent on location: in more populous, older cities, especially in Eurasia mass transit (rail, bus, etc.) predominates, while in smaller, younger cities, and large parts of North America and Australasia, commuting by personal automobile is more common. A small number of very wealthy people, and those working in remote locations around the world, also commute by air travel, often for a week or more at a time rather than the more typical daily commute. Transportation links that enable commuting also impact the physical layout of cities and regions, allowing a distinction to arise between mostly-residential suburbs and the more economically focused urban core of a city (process known as suburban sprawl), but the specifics of how that distinction is realized remain drastically different between societies, with Eurasian "suburbs" often being more densely populated than North American "urban cores".

History
The first separation between workplace and place of residence occurred as a result of the invention of the steam railway. The word commuter derives from the early days of rail travel in US cities, such as New York, Philadelphia, Boston and Chicago, where, in the 1840s, the railways engendered suburbs from which travelers paid a reduced or 'commuted' fare into the city. Later, the back formations "commute" and "commuter" were coined therefrom. Commuted tickets would usually allow the traveler to repeat the same journey as often as they liked during the period of validity: normally, the longer the period the cheaper the cost per day.

Before the 19th century, most workers lived less than an hour's walk from their work. The Industrial Revolution brought specialization of work and workplaces, and relocated most paid work from households and rural areas to factories in urban areas. Today, many people travel daily to work a long way from their own towns, cities, and villages, especially in industrialised societies. Depending on factors such as the high cost of housing in city centres, lack of public transit, and traffic congestion, modes of travel may include automobiles, motorcycles, trains, aircraft, buses, and bicycles. Where Los Angeles is infamous for its automobile gridlock, commuting in New York is closely associated with the subway; in London and Tokyo and several European cities, "commuter" is automatically associated with rail passengers. In the near future there may be another move away from the traditional "commute" with the introduction of flexible working. Some have suggested that many employees would be far more productive and live healthier, stress-free lives if the daily commute is removed completely.

Suburbs
Commuting has had a large impact on modern life. It has allowed cities to grow to sizes that were previously not practical, and it has led to the proliferation of suburbs. Many large cities or conurbations are surrounded by commuter belts, also known as metropolitan areas, commuter towns, dormitory towns, or bedroom communities. The prototypical commuter lives in one of these areas and travels daily to work or to school in the core city.

As urban sprawl pushes farther and farther away from central business districts, new businesses can appear in outlying cities, leading to the existence of the reverse commuter who lives in a core city but works in the suburbs, and to a type of secondary commuter who lives in a more distant exurb and works in the outlying city or industrial suburb.

Gender differences
A UK study, published in 2009, found that on average women suffer four times as much psychological stress from their work commute as men do. An Indian study conducted in Mangalore led by Edmond Fernandes stated that creating a gender sensitive commuter-centric road safety policy requires to be developed to protect women while commuting as they felt stressed and scared to travel alone, particularly at night.

Education
Institutions that have few dormitories or low or no student housing populations are called commuter schools in the United States, like community colleges.

Traffic
Most commuters travel at the same time of day, resulting in the morning and evening rush hours, with congestion on roads and public transport systems not designed or maintained well enough to cope with the peak demands. As an example, Interstate 405 located in Southern California is one of the busiest freeways in the United States. Commuters may sit up to two hours in traffic during rush hour. Construction work or collisions on the freeway distract and slow down commuters, contributing to even longer delays.

Pollution
Cars carrying only one occupant use fuel and roads less efficiently than shared cars or public transport, and increase traffic congestion. Commuting by car is a major factor contributing to air pollution. Carpool lanes can help commuters reach their destinations more quickly, encourage people to socialize, and spend time together, while reducing air pollution. Some governments and employers have introduced employee travel reduction programs that encourage such alternatives as carpooling and remote work. Some are also carpooling using Internet sites to save money. Alternatives like personal rapid transit have also been proposed to reap the energy-efficiency benefits of a mass transit system while maintaining the speed and convenience of individual transport.

Traffic emissions, such as from cars and trucks, also contribute. Airborne by-products from vehicle exhaust systems cause air pollution and are a major ingredient in the creation of smog in some large cities. The major culprits from transportation sources are carbon monoxide (CO), nitrogen oxides (NO and NOx), volatile organic compounds, sulfur dioxide, and hydrocarbons. Hydrocarbons are the main components of petroleum fuels such as gasoline and diesel fuel. These molecules react with sunlight, heat, ammonia, moisture, and other compounds to form the noxious vapours, ground level ozone, and particles that comprise smog.

Commuting trends in the United States
In the United States, the Census Bureau's American Community Survey (ACS) collects data on commuting times, allowing an analysis of average commute time by industry, location, and vehicle. According to the 2014 ACS, the average commute time for adults in the United States was 26.8 minutes. The occupations with the longest commutes were Construction and Mining (33.4 minutes), Computer Science and Math (31.8), and Business Operations Specialists (30.2), while those in the military had the shortest commute (21). In general, urban and suburban workers in the US have similar commute times (about 30 minutes), while rural workers have significantly shorter commutes (22.6 minutes). In the US, over 90% of workers commute by car, while about 5% commute by public transportation. Statistical models indicate that in addition to demographics and work duration, commute time is one of the most important determinants of discretionary time allocation by individuals.

Commuting College Students
The number of students who commute to college continues to increase significantly as the years go by. From 1996 to 2006 alone, the percentage of undergraduate students who commuted to campus began to increase at a rate of 30% to 50%.

In a study involving 10 universities in Canada, 61% of students reported that their commute was a challenge to campus participation, while 30% perceived it as a barrier to academic success. Factors influencing satisfaction included commute mode, duration, travel attitudes, and campus type. Notably, 72% of students had one-way commutes of one hour or less, 22% had commutes lasting between 60 and 90 minutes, and 9% faced commutes exceeding 90 minutes.

Commuting and the scarcity of local employment
Commuting is often made necessary due to local employment market factors which may stem from the decline of manufacturing (i.e., in cities where large manufacturing employers have either closed or laid off workers, with no other employers to absorb that loss) and, in general, the sheer lack of local employment. More specifically, that wages from local employers are seldom the same as what a worker household may require to sustain the household. As a result, the needs of worker households must be sustained and this leads to a wider field of job search beyond a local area to the next nearest city or metropolitan area, resulting in the requirement for commuting. Hence, in areas where little or no transit options exist that can facilitate a journey to work to meet the requirements of a worker schedule, the use of a car is therefore made necessary. This clearly is a personal choice that is borne of financial need but also acknowledges that the issue of how local economies sustain themselves is the overarching problem which needs to be addressed.

Social and health implications of commuting
Since commuting largely stems from a need to travel outside a home community to sustain a household income while facing a bleak local employment market, this comes with additional social and health implications. First, there is the increased risk of injury and accident while driving as distance and time in the vehicle increases, which is generally observed when operating a vehicle. Fatigue and hazardous road conditions add to this risk. Second, while income from employment is greater in other cities, stress from commuting factors become a factor for personal health. Ironically, stress from having to locate employment or being placed in a low-income situation might lead to a similar outcome. However, this is dichotomous with the satisfaction of a sustainable income and good employment, which is clearly the goal of an individual who is faced with commuting.

title: Commuting


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Honeyguide

Honeyguides (family Indicatoridae) are a family birds in the order Piciformes. They are also known as indicator birds, or honey birds, although the latter term is also used more narrowly to refer to species of the genus Prodotiscus. They have an Old World tropical distribution, with the greatest number of species in Africa and two in Asia. These birds are best known for their interaction with humans. Honeyguides are noted and named for one or two species that will deliberately lead humans (but, contrary to popular claims, most likely not honey badgers ) directly to bee colonies, so that they can feast on the grubs and beeswax that are left behind.

Taxonomy
The Indicatoridae were noted for their barbet-like structure and brood-parasitic behavior and morphologically considered unique among the non-passerines in having nine primaries. The phylogenetic relationship between the honeyguides and the eight other families that make up the order Piciformes is shown in the cladogram below. The number of species in each family is taken from the list maintained by Frank Gill, Pamela C. Rasmussen and David Donsker on behalf of the International Ornithological Committee (IOC).

Description

Most honeyguides are dull-colored, though some have bright yellow coloring in the plumage. All have light outer tail feathers, which are white in all the African species. The smallest species by body mass appears to be the green-backed honeyguide, at an average of 10.2 g, and by length appears to be the Cassin's honeyguide, at an average of 10 cm, while the largest species by weight is the lyre-tailed honeyguide, at 54.2 g, and by length, is the greater honeyguide, at 19.5 cm.

They are among the few birds that feed regularly on wax—beeswax in most species, and presumably the waxy secretions of scale insects in the genus Prodotiscus and to a lesser extent in Melignomon and the smaller species of Indicator. They also feed on waxworms which are the larvae of the waxmoth Galleria mellonella, on bee colonies, and on flying and crawling insects, spiders, and occasional fruits. Many species join mixed-species feeding flocks.

Guiding
Honeyguides are named for a remarkable habit seen in one or two species: guiding humans to bee colonies. Once the hive is open and the honey is taken, the bird feeds on larvae and wax. This behavior has been studied in the greater honeyguide; some authorities (following Friedmann, 1955) state that it also occurs in the scaly-throated honeyguide, while others disagree. Wild honeyguides understand various types of human calls that attract them to engage in the foraging mutualism. In northern Tanzania, honeyguides partner with Hadza hunter-gatherers, and the bird assistance has been shown to increase honey-hunters' rates of finding bee colonies by 560%, and led men to significantly higher yielding nests than those found without honeyguides. Contrary to most depictions of the human-honeyguide relationship, the Hadza did not actively repay honeyguides, but instead, hid, buried, and burned honeycomb, with the intent of keeping the bird hungry and thus more likely to guide again. Some experts believe that honeyguide co-evolution with humans goes back to the stone-tool making human ancestor Homo erectus, about 1.9million years ago. Despite popular belief, no evidence indicates that honeyguides guide the honey badger; though videos about this exist, there have been accusations that they were staged.

Although most members of the family are not known to recruit "followers" in their quest for wax, they are also referred to as "honeyguides" by linguistic extrapolation.

Breeding
The breeding behavior of eight species in Indicator and Prodotiscus is known. They are all brood parasites that lay one egg in a nest of another species, laying eggs in series of about five during a period of 5–7 days. Most favor hole-nesting species, often the related barbets and woodpeckers, but Prodotiscus parasitizes cup-nesters such as white-eyes and warblers. Honeyguide nestlings have been known to physically eject their hosts' chicks from the nests and they have needle-sharp hooks on their beaks with which they puncture the hosts' eggs or kill the nestlings.

African honeyguide birds are known to lay their eggs in underground nests of other bee-eating bird species. The honeyguide chicks kill the hatchlings of the host using their needle-sharp beaks just after hatching, much as cuckoo hatchlings do. The honeyguide mother ensures her chick hatches first by internally incubating the egg for an extra day before laying it, so that it has a head start in development compared to the hosts' offspring.

title: Honeyguide


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Defenders of the Faith

Defenders of the Faith is the ninth studio album by English heavy metal band Judas Priest, released on 13 January 1984 in the US and on 20 January 1984 in the UK. The album was certified platinum by the RIAA, and spawned the singles "Freewheel Burning", "Some Heads Are Gonna Roll", and "Love Bites".

Recording and release
Defenders of the Faith was recorded at Ibiza Sound Studios, Ibiza, Spain, and mixed at DB Recording Studios and Bayshore Recording Studios in Coconut Grove, Miami, Florida. The LP and cassette tape were released on 13 January 1984, and the album appeared on CD in July. A remastered CD was released in May 2001. Simultaneously with the album's release, the band kicked off their tour in Europe, with the bulk of concerts taking place in North America during the spring and summer.

Stylistically, Defenders of the Faith did not greatly depart from its predecessor and featured a similar formula of short, up-tempo metal anthems with stadium shout-along choruses, although progressive elements returned on some tracks such as "The Sentinel". The track "Rock Hard Ride Free" is actually a re-working of a track entitled "Fight for Your Life", recorded during the 1982 Screaming For Vengeance sessions but not included on that album.

The album was an immediate success, only going one spot below Screaming for Vengeance on the US Billboard 100 Albums Chart. Some critics nonetheless objected to the lack of a standout single comparable to "Breaking the Law" or "You've Got Another Thing Comin', and the album's general similarity to Screaming for Vengeance.

The 30th-anniversary release of the album (released in March 2015) came with a double CD of a live show recorded on 5 May 1984 at the Long Beach Arena in Long Beach, California on their Defenders of the Faith Tour and was originally recorded for a radio broadcast.

Packaging
The cover art by Doug Johnson (who also designed the Hellion in Screaming for Vengeance) depicts the Metallian, a horned, tiger-like land assault creature with Gatling guns and tank tracks conceptualized by the band. The back cover contains a message:

"Rising from darkness where Hell hath no mercy and the screams for vengeance echo on forever. Only those who keep the faith shall escape the wrath of the Metallian ... Master of all metal."

Controversy
"Eat Me Alive" was listed at number 3 on the Parents Music Resource Center's "Filthy Fifteen", a list of 15 songs the organization found most objectionable. PMRC co-founder Tipper Gore stated the song was about oral sex at gunpoint. In response to the allegations, Priest recorded the song "Parental Guidance" on the follow-up album Turbo.

"In a uniquely British way, Rob's S&M lyrics were intended to be tongue in cheek—and certainly not 'corrupting', as Tipper Gore and the Parents Music Resource Center (PMRC) took them to be. They certainly didn't warrant being included on the PMRC's 'Filthy 15' list a few months after the album was released. For us, the song was a bit of fun—but I won’t deny that we included it with full knowledge that it would get media attention. Little did we know at that time that its inclusion on the 'Filthy 15' would be the precursor to a far more disturbing predicament for us."

Promotion
In December 1983, the band did a short tour playing dates in the UK and Germany introducing new single "Freewheel Burning" in the set. In January 1984, the band embarked on the Metal Conqueror Tour across Europe, North America and Japan. On this tour, the band played every song from the album live, with the exception of "Eat Me Alive". During the band's 2008 tour in support of Nostradamus, they played many songs which had never been played live before, one of them being "Eat Me Alive". To date, this made Defenders of the Faith the second Judas Priest album from which every song had been played live (the first being Rocka Rolla), followed by British Steel during the 2009, British Steel 30th anniversary tour. By the end of 1984, Defenders of the Faith sold more than 800,000 copies worldwide.

Legacy

 * "Jawbreaker" was covered by Rage for the single "Higher than the Sky" and also appeared on the tribute album A Tribute to Judas Priest: Legends of Metal and All G.U.N. Bonustracks CD. In 2010, "Jawbreaker" was covered by Swedish power metal band Sabaton on the Re-Armed Edition of their album Metalizer. In 2017, "Jawbreaker" was covered by Swiss band Burning Witches on their debut self-titled album.
 * "The Sentinel" was covered by Machine Head for the special edition version of their 2011 album Unto the Locust as well as Heavens Gate for the Japan version of their 1996 album Planet E.
 * "Night Comes Down" was covered by Katatonia for the Japanese edition of their 2016 album The Fall of Hearts.

Track listing
30th Anniversary Edition – Bonus Live CDs

Personnel

 * Judas Priest
 * Rob Halford – vocals
 * K. K. Downing – guitars
 * Glenn Tipton – guitars
 * Ian Hill – bass
 * Dave Holland – drums

 * Production
 * Produced by Tom Allom
 * Engineered by Mark Dodson, assisted by Christian Eser, Bruce Hensal, David Roeder, Ben King, and Buddy Thornton
 * Cover design by Doug Johnson, based on a concept by Judas Priest

title: Defenders of the Faith


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Masters and Johnson

The Masters and Johnson research team, composed of William H. Masters and Virginia E. Johnson, pioneered research into the nature of human sexual response and the diagnosis and treatment of sexual disorders and dysfunctions from 1957 until the 1990s.

The work of Masters and Johnson began in the Department of Obstetrics and Gynecology at Washington University in St. Louis and was continued at the independent not-for-profit research institution they founded in St. Louis in 1964, originally called the Reproductive Biology Research Foundation and renamed the Masters and Johnson Institute in 1978.

In the initial phase of Masters and Johnson's studies, from 1957 until 1965, they recorded some of the first laboratory data on the anatomy and physiology of human sexual response based on direct observation of 382 women and 312 men in what they conservatively estimated to be "10,000 complete cycles of sexual response". Their findings, particularly on the nature of female sexual arousal (for example, describing the mechanisms of vaginal lubrication and debunking the earlier widely held notion that vaginal lubrication originated from the cervix) and orgasm (showing that the physiology of orgasmic response was identical whether stimulation was clitoral or vaginal, and, separately, proving that some women were capable of being multiorgasmic), dispelled many long-standing misconceptions.

They jointly wrote two classic texts in the field, Human Sexual Response and Human Sexual Inadequacy, published in 1966 and 1970 respectively. Both of these books were best-sellers and were translated into more than thirty languages. The team has been inducted into the St. Louis Walk of Fame. Additionally, they are the focus of a television series called Masters of Sex for Showtime based on the 2009 biography by author Thomas Maier.

Research work
Masters and Johnson met in 1957 when William Masters hired Virginia Johnson as a research assistant to undertake a comprehensive study of human sexuality. According to author Thomas Maier, as part of their clinical research Masters and Johnson observed paid volunteers engaging in sexual activity while hooked to wires in their lab. At Masters's request, Masters and Johnson engaged in intercourse as subjects of their own study and eventually became lovers. Maier stated that Masters spent more time in the lab with Johnson than he did with his wife Libby and their children, and also spent summer vacations together with Johnson. By the time Masters divorced his first wife in 1971, associates believed that he and Johnson essentially lived together and worked and traveled together seven days a week. Masters and Johnson married in 1971 but then later divorced on March 18, 1993, in the Circuit Court of St. Louis County; they nonetheless continued to work together professionally.

Previously, the study of human sexuality (sexology) had been a largely neglected field of study due to the restrictive social conventions of the time, with prostitution as a notable exception.

Alfred Kinsey and colleagues at Indiana University had previously published two volumes on sexual behavior in the human male and female (known as the Kinsey Reports), in 1948 and 1953 respectively, both of which had been revolutionary and controversial in their time. Kinsey's work, however, had mainly investigated the frequency with which certain behaviors occurred in the population and was based on personal interviews, not on laboratory observation. In contrast, Masters and Johnson set about to study the structure, psychology, and physiology of sexual behavior through observing and measuring masturbation and sexual intercourse in the laboratory.

Initially, participants used in their experiments were prostitutes. Masters and Johnson explained that they were a socially isolated group of people, they were knowledgeable about sex, and that they were willing to cooperate with the study. Of the 145 prostitutes who participated, only a select few were further evaluated for their genital anatomy and their physiological responses. In later studies, however, Masters and Johnson recruited 382 women and 312 men from the community. The vast majority of participants were white, had higher education levels, and most participants were married couples.

As well as recording some of the first physiological data from the human body and sex organs during sexual excitation, they also framed their findings and conclusions in language that espoused sex as a healthy and natural activity that could be enjoyed as a source of pleasure and intimacy.

The era in which their research was conducted permitted the use of methods that had not been attempted before, and that have not been attempted since: "[M]en and women were designated as 'assigned partners' and arbitrarily paired with each other to create 'assigned couples'."

Four-stage model of the sexual response
One of the most enduring and important aspects of their work has been the four stage model of sexual response, which they described as the human sexual response cycle and defined as:
 * Excitement phase (initial arousal)
 * Plateau phase (at full arousal, but not yet at orgasm)
 * Orgasm
 * Resolution phase (after orgasm)

Their model shows no difference between Sigmund Freud's purported categories of "vaginal orgasm" and "clitoral orgasm": the physiological response was identical, even if the stimulation was in a different place.

Masters and Johnson's findings also revealed that men undergo a refractory period following orgasm during which they are not able to ejaculate again, whereas there is no refractory period in women: this makes women capable of multiple orgasm. They also were the first to describe the phenomenon of the rhythmic contractions of orgasm in both sexes occurring initially in 0.8 second intervals and then gradually slowing in both speed and intensity.

Sexual response in the aging person
Masters and Johnson were the first to conduct research on the sexual responsiveness of older adults, finding that given a state of reasonably good health and the availability of an interested and interesting partner, there was no absolute age at which sexual abilities disappeared. While they noted that there were specific changes to the patterns of male and female sexual responses with aging – for example, it takes older men longer to become aroused and they typically require more direct genital stimulation, and the speed and amount of vaginal lubrication tends to diminish with age as well – they noted that many older men and women are perfectly capable of excitement and orgasm well into their seventies and beyond, a finding that has been confirmed in population-based epidemiological research on sexual function in the elderly.

Laboratory comparison of homosexual male versus homosexual female sex
Masters and Johnson randomly assigned two men into couples and two women into couples and then observed them having sex in the laboratory, at the Masters and Johnson Institute. They provided their observations in Homosexuality in Perspective:

"Assigned male homosexual study subjects A, B, and C..., interacting in the laboratory with previously unknown male partners, did discuss procedural matters with these partners, but quite briefly. Usually, the discussion consisted of just a question or a suggestion, but often it was limited to nonverbal communicative expressions such as eye contact or hand movement, any of which usually proved sufficient to establish the protocol of partner interaction. No coaching or suggestions were made by the research team."

According to Masters and Johnson, this pattern differed in the female homosexual couples:

"While initial stimulative activity tended to be on a mutual basis, in short order control of the specific sexual experience usually was assumed by one partner. The assumption of control was established without verbal communication and frequently with no obvious nonverbal direction, although on one occasion discussion as to procedural strategy continued even as the couple was interacting physically."

Sexual dysfunction
Their research into the anatomy and physiology of sexual response was a springboard to developing a clinical approach to the treatment of sexual problems in a revolutionary manner. Prior to 1970, when they described their treatment program to the world for the first time, sexual dysfunctions such as premature ejaculation, impotence, vaginismus, and female frigidity had been generally treated by long-term (multi-year) psychotherapy or psychoanalysis with very low rates of success. Masters and Johnson revolutionized things by devising a form of rapid treatment (2 week) psychotherapy always involving a couple, rather than just an individual, working with a male-female therapist team that resulted in a success rate of more than 80%. This was strictly a talking therapy – couples in their sex therapy program were never observed in sexual activity.

Treatment of homosexual behavior
From 1968 to 1977, the Masters and Johnson Institute ran a program to convert homosexuals to heterosexuality. This program reported a 71.6% success rate over a six-year treatment period. At the time of their earlier work, homosexuality was classified as a psychological disorder by the American Psychiatric Association, a classification which was repealed in 1973.

Thomas Maier stated "that Virginia Johnson had serious reservations about Masters' conversion theory, and she suspected that, at worst, the results of the study may have been fabricated by William Masters". Psychiatrist Robert C. Kolodny, a clinical associate of the Masters', also expressed reservations about the veracity of the findings in Masters' book on the topic and alleged that Masters had not kept files of the case studies cited in the book. Shortly before the book was published, he wrote Masters a two-page letter expressing Johnson's and Kolodny's reservations on the alleged successful reconversion findings and urging him to reconsider publication of the book, to no avail. As homosexuality was on the verge of being dropped from the Diagnostic and Statistical Manual of Mental Disorders (DSM), Masters's insistence on publishing the book proved to be tone-deaf and was shunned by book critics.

Criticisms
Some sex researchers, Shere Hite in particular, have focused on understanding how individuals regard sexual experience and the meaning it holds for them. Hite has criticized Masters and Johnson's work for uncritically incorporating cultural attitudes on sexual behavior into their research; for example, her work concluded that the 70% of women who do not have orgasms through intercourse are able to achieve orgasm easily by masturbation. She, as well as Elisabeth Lloyd, have criticized Masters and Johnson's argument that enough clitoral stimulation to achieve orgasm should be provided by thrusting during intercourse, and the inference that the failure of this is a sign of female "sexual dysfunction". While not denying that both Kinsey and Masters and Johnson have made major contributions to sex research, she believes that people must understand the cultural and personal construction of sexual experience to make the research relevant to sexual behavior outside the laboratory. Hite's work, however, has been challenged for methodological defects.

Moreover, Masters and Johnson's research methodology has been criticized. First, Paul Robinson argues that because many of their participants were sex workers, it is highly likely that these individuals have had more sexual experience and are more comfortable with sex and sexuality in general. He says that one must approach these results with caution, because the participants do not represent the general population.

Other researchers have argued that Masters and Johnson eliminated same-sex attracted participants when studying the human sexual response cycle, which also limits the generalizability of their results.

Furthermore, Masters and Johnson have been criticized for studying sexual behaviors in the laboratory. While they attempted to make participants as comfortable as possible in the lab by giving them a "practice session" before their behavior was recorded, critics have argued that two people engaging in sexual activity in a lab is a different experience compared to being in the privacy and comfort of one's home.

Another persistent critique was that despite her extensive years of clinical work, Virginia Johnson never earned a university degree and often did not correct those who referred to her in the press or in person as "Dr. Johnson."

Television
Masters and Johnson appeared together on the NBC daily news program America Alive! in the second half of 1978, as authorities on the subject of sex.

In popular culture
The American cable network Showtime debuted Masters of Sex, a dramatic television series based on the 2009 biography of the same name, on September 29, 2013. The series stars Michael Sheen as Masters and Lizzy Caplan as Johnson. (The same actors briefly portrayed "Masters and Johnson", as similar characters but in the present day, in The Simpsons episode "Kamp Krustier".)

Masters and Johnson were referenced in a 1974 Italian comedy directed by Bruno Corbucci, Il trafficone.

Masters and Johnson are the subject of a trivia question in season 1 episode 21 (1983) of Family Ties.

Masters and Johnson are referenced in season 6 episode 2 (1990) of The Golden Girls.

One character in the film Mallrats (1995) is nicknamed Masters & Johnson for her bizarre school project of studying sex.

Publications

 * 1981 edition ISBN 978-0553204292.

title: Masters and Johnson


text:
Talk:Gyonshee

These appear to be from some gaming system, at first sight... Try Googling... Karada

 * There are only 19 Google pages, the rest are completely repetitions. I've redirected it to Hopping corpse, on which the name "Gyonshee" is based. --Menchi 02:10 8 Jul 2003 (UTC)

title: Talk:Gyonshee


text:
Thermodynamic potential

A thermodynamic potential (or more accurately, a thermodynamic potential energy) is a scalar quantity used to represent the thermodynamic state of a system. Just as in mechanics, where potential energy is defined as capacity to do work, similarly different potentials have different meanings. The concept of thermodynamic potentials was introduced by Pierre Duhem in 1886. Josiah Willard Gibbs in his papers used the term fundamental functions. While thermodynamic potentials cannot be measured directly, they can be predicted using computational chemistry.

One main thermodynamic potential that has a physical interpretation is the internal energy $U$. It is the energy of configuration of a given system of conservative forces (that is why it is called potential) and only has meaning with respect to a defined set of references (or data). Expressions for all other thermodynamic energy potentials are derivable via Legendre transforms from an expression for $U$. In other words, each thermodynamic potential is equivalent to other thermodynamic potentials; each potential is a different expression of the others.

In thermodynamics, external forces, such as gravity, are counted as contributing to total energy rather than to thermodynamic potentials. For example, the working fluid in a steam engine sitting on top of Mount Everest has higher total energy due to gravity than it has at the bottom of the Mariana Trench, but the same thermodynamic potentials. This is because the gravitational potential energy belongs to the total energy rather than to thermodynamic potentials such as internal energy.

Description and interpretation
Five common thermodynamic potentials are:

where $T$ = temperature, $S$ = entropy, $p$ = pressure, $V$ = volume. $N_{i}$ is the number of particles of type $i$ in the system and $μ_{i}$ is the chemical potential for an $i$-type particle. The set of all $N_{i}$ are also included as natural variables but may be ignored when no chemical reactions are occurring which cause them to change. The Helmholtz free energy is in ISO/IEC standard called Helmholtz energy or Helmholtz function. It is often denoted by the symbol $F$, but the use of $A$ is preferred by IUPAC, ISO and IEC.

These five common potentials are all potential energies, but there are also entropy potentials. The thermodynamic square can be used as a tool to recall and derive some of the potentials.

Just as in mechanics, where potential energy is defined as capacity to do work, similarly different potentials have different meanings like the below: From these meanings (which actually apply in specific conditions, e.g. constant pressure, temperature, etc.), for positive changes (e.g., $ΔU > 0$), we can say that $ΔU$ is the energy added to the system, $ΔF$ is the total work done on it, $ΔG$ is the non-mechanical work done on it, and $ΔH$ is the sum of non-mechanical work done on the system and the heat given to it.
 * Internal energy ($U$) is the capacity to do work plus the capacity to release heat.
 * Gibbs energy ($G$) is the capacity to do non-mechanical work.
 * Enthalpy ($H$) is the capacity to do non-mechanical work plus the capacity to release heat.
 * Helmholtz energy ($F$) is the capacity to do mechanical work plus non-mechanical work.

Note that the sum of internal energy is conserved, but the sum of Gibbs energy, or Helmholtz energy, are not conserved, despite being named "energy". They can be better interpreted as the potential to perform "useful work", and the potential can be wasted.

Thermodynamic potentials are very useful when calculating the equilibrium results of a chemical reaction, or when measuring the properties of materials in a chemical reaction. The chemical reactions usually take place under some constraints such as constant pressure and temperature, or constant entropy and volume, and when this is true, there is a corresponding thermodynamic potential that comes into play. Just as in mechanics, the system will tend towards a lower value of a potential and at equilibrium, under these constraints, the potential will take the unchanging minimum value. The thermodynamic potentials can also be used to estimate the total amount of energy available from a thermodynamic system under the appropriate constraint.

In particular: (see principle of minimum energy for a derivation)

 * When the entropy $S$ and "external parameters" (e.g. volume) of a closed system are held constant, the internal energy $U$ decreases and reaches a minimum value at equilibrium. This follows from the first and second laws of thermodynamics and is called the principle of minimum energy. The following three statements are directly derivable from this principle.
 * When the temperature $T$ and external parameters of a closed system are held constant, the Helmholtz free energy $F$ decreases and reaches a minimum value at equilibrium.
 * When the pressure $p$ and external parameters of a closed system are held constant, the enthalpy $H$ decreases and reaches a minimum value at equilibrium.
 * When the temperature $T$, pressure $p$ and external parameters of a closed system are held constant, the Gibbs free energy $G$ decreases and reaches a minimum value at equilibrium.

Natural variables
For each thermodynamic potential, there are thermodynamic variables that need to be held constant to specify the potential value at a thermodynamical equilibrium state, such as independent variables for a mathematical function. These variables are termed the natural variables of that potential. The natural variables are important not only to specify the potential value at the equilibrium, but also because if a thermodynamic potential can be determined as a function of its natural variables, all of the thermodynamic properties of the system can be found by taking partial derivatives of that potential with respect to its natural variables and this is true for no other combination of variables. If a thermodynamic potential is not given as a function of its natural variables, it will not, in general, yield all of the thermodynamic properties of the system.

The set of natural variables for each of the above four thermodynamic potentials is formed from a combination of the $T$, $S$, $p$, $V$ variables, excluding any pairs of conjugate variables; there is no natural variable set for a potential including the $T$-$S$ or $p$-$V$ variables together as conjugate variables for energy. An exception for this rule is the $N_{i}$ − $μ_{i}$ conjugate pairs as there is no reason to ignore these in the thermodynamic potentials, and in fact we may additionally define the four potentials for each species. Using IUPAC notation in which the brackets contain the natural variables (other than the main four), we have:

If there is only one species, then we are done. But, if there are, say, two species, then there will be additional potentials such as $$U[\mu_1,\mu_2] = U-\mu_1 N_1-\mu_2 N_2$$ and so on. If there are $D$ dimensions to the thermodynamic space, then there are $2^{D}$ unique thermodynamic potentials. For the most simple case, a single phase ideal gas, there will be three dimensions, yielding eight thermodynamic potentials.

The fundamental equations
The definitions of the thermodynamic potentials may be differentiated and, along with the first and second laws of thermodynamics, a set of differential equations known as the fundamental equations follow. (Actually they are all expressions of the same fundamental thermodynamic relation, but are expressed in different variables.) By the first law of thermodynamics, any differential change in the internal energy $U$ of a system can be written as the sum of heat flowing into the system subtracted by the work done by the system on the environment, along with any change due to the addition of new particles to the system:

 * $$\mathrm{d}U = \delta Q - \delta W+\sum_i \mu_i\,\mathrm{d}N_i$$

where $δQ$ is the infinitesimal heat flow into the system, and $δW$ is the infinitesimal work done by the system, $μ_{i}$ is the chemical potential of particle type $i$ and $N_{i}$ is the number of the type $i$ particles. (Neither $δQ$ nor $δW$ are exact differentials, i.e., they are thermodynamic process path-dependent. Small changes in these variables are, therefore, represented with $δ$ rather than $d$.)

By the second law of thermodynamics, we can express the internal energy change in terms of state functions and their differentials. In case of reversible changes we have:

 * $$\delta Q = T\,\mathrm{d}S$$

 * $$\delta W = p\,\mathrm{d}V$$

where
 * $T$ is temperature,
 * $S$ is entropy,
 * $p$ is pressure,

and $V$ is volume, and the equality holds for reversible processes.

This leads to the standard differential form of the internal energy in case of a quasistatic reversible change:

 * $$\mathrm{d}U = T\mathrm{d}S - p\mathrm{d}V+\sum_i \mu_i\,\mathrm{d}N_i$$

Since $U$, $S$ and $V$ are thermodynamic functions of state (also called state functions), the above relation also holds for arbitrary non-reversible changes. If the system has more external variables than just the volume that can change, the fundamental thermodynamic relation generalizes to:

 * $$dU = T\,\mathrm{d}S - p\,\mathrm{d}V + \sum_j \mu_j\,\mathrm{d}N_j + \sum_i X_i \, \mathrm{d}x_{i} $$

Here the $X_{i}$ are the generalized forces corresponding to the external variables $x_{i}$.

Applying Legendre transforms repeatedly, the following differential relations hold for the four potentials (fundamental thermodynamic equations or fundamental thermodynamic relation):

The infinitesimals on the right-hand side of each of the above equations are of the natural variables of the potential on the left-hand side. Similar equations can be developed for all of the other thermodynamic potentials of the system. There will be one fundamental equation for each thermodynamic potential, resulting in a total of $2^{D}$ fundamental equations.

The differences between the four thermodynamic potentials can be summarized as follows:

 * $$\mathrm{d}(pV) = \mathrm{d}H - \mathrm{d}U = \mathrm{d}G - \mathrm{d}F $$
 * $$\mathrm{d}(TS) = \mathrm{d}U - \mathrm{d}F = \mathrm{d}H - \mathrm{d}G $$

The equations of state
We can use the above equations to derive some differential definitions of some thermodynamic parameters. If we define $Φ$ to stand for any of the thermodynamic potentials, then the above equations are of the form:

 * $$\mathrm{d}\Phi=\sum_i x_i\,\mathrm{d}y_i$$

where $x_{i}$ and $y_{i}$ are conjugate pairs, and the $y_{i}$ are the natural variables of the potential $Φ$. From the chain rule it follows that:

 * $$x_j=\left(\frac{\partial \Phi}{\partial y_j}\right)_{\{y_{i\ne j}\}}$$

where ${y_{i ≠ j} }$ is the set of all natural variables of $Φ$ except $y_{j}$ that are held as constants. This yields expressions for various thermodynamic parameters in terms of the derivatives of the potentials with respect to their natural variables. These equations are known as equations of state since they specify parameters of the thermodynamic state. If we restrict ourselves to the potentials $U$ (Internal energy), $F$ (Helmholtz energy), $H$ (Enthalpy) and $G$ (Gibbs energy), then we have the following equations of state (subscripts showing natural variables that are held as constants):

+T=\left(\frac{\partial U}{\partial S}\right)_{V,\{N_i\}} =\left(\frac{\partial H}{\partial S}\right)_{p,\{N_i\}} $$

-p=\left(\frac{\partial U}{\partial V}\right)_{S,\{N_i\}} =\left(\frac{\partial F}{\partial V}\right)_{T,\{N_i\}} $$

+V=\left(\frac{\partial H}{\partial p}\right)_{S,\{N_i\}} =\left(\frac{\partial G}{\partial p}\right)_{T,\{N_i\}} $$

-S=\left(\frac{\partial G}{\partial T}\right)_{p,\{N_i\}} =\left(\frac{\partial F}{\partial T}\right)_{V,\{N_i\}} $$

~\mu_j= \left(\frac{\partial \phi}{\partial N_j}\right)_{X,Y,\{N_{i\ne j}\}} $$

where, in the last equation, $ϕ$ is any of the thermodynamic potentials ($U$, $F$, $H$, or $G$), and $${X,Y,\{N_{i\ne j}\}}$$ are the set of natural variables for that potential, excluding $N_{i}$. If we use all thermodynamic potentials, then we will have more equations of state such as

-N_j=\left(\frac{\partial U[\mu_j]}{\partial \mu_j}\right)_{S,V,\{N_{i\ne j}\}} $$

and so on. In all, if the thermodynamic space is $D$ dimensions, then there will be $D$ equations for each potential, resulting in a total of $D 2^{D}$ equations of state because $2^{D}$ thermodynamic potentials exist. If the $D$ equations of state for a particular potential are known, then the fundamental equation for that potential (i.e., the exact differential of the thermodynamic potential) can be determined. This means that all thermodynamic information about the system will be known because the fundamental equations for any other potential can be found via the Legendre transforms and the corresponding equations of state for each potential as partial derivatives of the potential can also be found.

Measurement of thermodynamic potentials
The above equations of state suggest methods to experimentally measure changes in the thermodynamic potentials using physically measurable parameters. For example the free energy expressions

+V=\left(\frac{\partial G}{\partial p}\right)_{T,\{N_i\}} $$

and

-p=\left(\frac{\partial F}{\partial V}\right)_{T,\{N_i\}} $$

can be integrated at constant temperature and quantities to obtain:

\Delta G = \int_{P1}^{P2}V\,\mathrm{d}p\,\,\,\, $$(at constant T, {Nj} )

\Delta F = -\int_{V1}^{V2}p\,\mathrm{d}V\,\,\,\, $$(at constant T, {Nj} )

which can be measured by monitoring the measurable variables of pressure, temperature and volume. Changes in the enthalpy and internal energy can be measured by calorimetry (which measures the amount of heat ΔQ released or absorbed by a system). The expressions

+T=\left(\frac{\partial U}{\partial S}\right)_{V,\{N_i\}} =\left(\frac{\partial H}{\partial S}\right)_{p,\{N_i\}} $$

can be integrated:

\Delta H = \int_{S1}^{S2}T\,\mathrm{d}S = \Delta Q\,\,\,\, $$(at constant P, {Nj} )

\Delta U = \int_{S1}^{S2}T\,\mathrm{d}S = \Delta Q\,\,\,\, $$(at constant V, {Nj} )

Note that these measurements are made at constant {Nj } and are therefore not applicable to situations in which chemical reactions take place.

The Maxwell relations
Again, define $x_{i}$ and $y_{i}$ to be conjugate pairs, and the $y_{i}$ to be the natural variables of some potential $Φ$. We may take the "cross differentials" of the state equations, which obey the following relationship:

\left(\frac{\partial}{\partial y_j} \left(\frac{\partial \Phi}{\partial y_k} \right)_{\{y_{i\ne k}\}} \right)_{\{y_{i\ne j}\}} = \left(\frac{\partial}{\partial y_k} \left(\frac{\partial \Phi}{\partial y_j} \right)_{\{y_{i\ne j}\}} \right)_{\{y_{i\ne k}\}} $$

From these we get the Maxwell relations. There will be $(D − 1)⁄2$ of them for each potential giving a total of $D(D − 1)⁄2$ equations in all. If we restrict ourselves the $U$, $F$, $H$, $G$

\left(\frac{\partial T}{\partial V}\right)_{S,\{N_i\}} = -\left(\frac{\partial p}{\partial S}\right)_{V,\{N_i\}} $$

\left(\frac{\partial T}{\partial p}\right)_{S,\{N_i\}} = +\left(\frac{\partial V}{\partial S}\right)_{p,\{N_i\}} $$

\left(\frac{\partial S}{\partial V}\right)_{T,\{N_i\}} = +\left(\frac{\partial p}{\partial T}\right)_{V,\{N_i\}} $$

\left(\frac{\partial S}{\partial p}\right)_{T,\{N_i\}} = -\left(\frac{\partial V}{\partial T}\right)_{p,\{N_i\}} $$

Using the equations of state involving the chemical potential we get equations such as:

\left(\frac{\partial T}{\partial N_j}\right)_{V,S,\{N_{i\ne j}\}} = \left(\frac{\partial \mu_j}{\partial S}\right)_{V,\{N_i\}} $$

and using the other potentials we can get equations such as:

\left(\frac{\partial N_j}{\partial V}\right)_{S,\mu_j,\{N_{i\ne j}\}} = -\left(\frac{\partial p}{\partial \mu_j}\right)_{S,V\{N_{i\ne j}\}} $$

\left(\frac{\partial N_j}{\partial N_k}\right)_{S,V,\mu_j,\{N_{i\ne j,k}\}} = -\left(\frac{\partial \mu_k}{\partial \mu_j}\right)_{S,V\{N_{i\ne j}\}} $$

Euler relations
Again, define $x_{i}$ and $y_{i}$ to be conjugate pairs, and the $y_{i}$ to be the natural variables of the internal energy. Since all of the natural variables of the internal energy $U$ are extensive quantities

 * $$U(\{\alpha y_i\})=\alpha U(\{y_i\})$$

it follows from Euler's homogeneous function theorem that the internal energy can be written as:

 * $$U(\{y_i\})=\sum_j y_j\left(\frac{\partial U}{\partial y_j}\right)_{\{y_{i\ne j}\}}$$

From the equations of state, we then have:

 * $$U=TS-pV+\sum_i \mu_i N_i$$

This formula is known as an Euler relation, because Euler's theorem on homogeneous functions leads to it. (It was not discovered by Euler in an investigation of thermodynamics, which did not exist in his day.).

Substituting into the expressions for the other main potentials we have:

 * $$F= -pV+\sum_i \mu_i N_i$$

 * $$H=TS  +\sum_i \mu_i N_i$$

 * $$G=     \sum_i \mu_i N_i$$

As in the above sections, this process can be carried out on all of the other thermodynamic potentials. Thus, there is another Euler relation, based on the expression of entropy as a function of internal energy and other extensive variables. Yet other Euler relations hold for other fundamental equations for energy or entropy, as respective functions of other state variables including some intensive state variables.

The Gibbs–Duhem relation
Deriving the Gibbs–Duhem equation from basic thermodynamic state equations is straightforward. Equating any thermodynamic potential definition with its Euler relation expression yields:

 * $$U=TS-PV+\sum_i \mu_i N_i$$

Differentiating, and using the second law:

 * $$\mathrm{d}U=T\mathrm{d}S-P\mathrm{d}V+\sum_i\mu_i\,\mathrm{d}N_i$$

yields:

 * $$0=S\mathrm{d}T-V\mathrm{d}P+\sum_i N_i \mathrm{d}\mu_i$$

Which is the Gibbs–Duhem relation. The Gibbs–Duhem is a relationship among the intensive parameters of the system. It follows that for a simple system with $I$ components, there will be $I + 1$ independent parameters, or degrees of freedom. For example, a simple system with a single component will have two degrees of freedom, and may be specified by only two parameters, such as pressure and volume for example. The law is named after Josiah Willard Gibbs and Pierre Duhem.

Stability Conditions
As the internal energy is a convex function of entropy and volume, the stability condition requires that the second derivative of internal energy with entropy or volume to be positive. It is commonly expressed as $$d^2U>0$$. Since the maximum principle of entropy is equivalent to minimum principle of internal energy, the combined criteria for stability or thermodynamic equilibrium is expressed as $$d^2U>0$$ and $$dU=0$$ for parameters, entropy and volume. This is analogous to $$d^2S<0$$ and $$dS=0$$ condition for entropy at equilibrium. The same concept can be applied to the various thermodynamic potentials by identifying if they are convex or concave of respective their variables.

$$\biggl({\partial^2F\over\partial T^2}\biggr)_{V,N}\leq0$$ and $$\biggl({\partial^2F\over\partial V^2}\biggr)_{T,N}\geq0$$

Where Helmholtz energy is a concave function of temperature and convex function of volume.

$$\biggl({\partial^2H\over\partial P^2}\biggr)_{S,N}\leq0$$ and $$\biggl({\partial^2H\over\partial S^2}\biggr)_{P,N}\geq0$$

Where enthalpy is a concave function of pressure and convex function of entropy.

$$\biggl({\partial^2G\over\partial T^2}\biggr)_{P,N}\leq0$$ and $$\biggl({\partial^2G\over\partial P^2}\biggr)_{T,N}\leq0$$

Where Gibbs potential is a concave function of both pressure and temperature.

In general the thermodynamic potentials (the internal energy and its Legendre transforms), are convex functions of their extrinsic variables and concave functions of intrinsic variables. The stability conditions impose that isothermal compressibility is positive and that for non-negative temperature, $$C_P>C_V$$.

Chemical reactions
Changes in these quantities are useful for assessing the degree to which a chemical reaction will proceed. The relevant quantity depends on the reaction conditions, as shown in the following table. $Δ$ denotes the change in the potential and at equilibrium the change will be zero.

Most commonly one considers reactions at constant $V$ and $p$, so the Gibbs free energy is the most useful potential in studies of chemical reactions.

title: Thermodynamic potential