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12,108,792 | https://en.wikipedia.org/wiki/Positive%20adult%20development | Positive adult development is a subfield of developmental psychology that studies positive development during adulthood. It is one of four major forms of adult developmental study that can be identified, according to Michael Commons; the other three forms are directionless change, stasis, and decline. Commons also further divided the concept of positive adult development into six distinct areas of study: hierarchical complexity (i.e., orders or stages), knowledge, experience, expertise, wisdom, and spirituality.
The development of people has focused on children and adolescence with several theories as proposed by Freud, Piaget, and Binet. Research in positive adult development supports the theory that development occurs during adulthood. Recent studies indicate that such development is useful in predicting things such as an individual's health, life satisfaction, and degree of contribution to society. Current research supports the idea that personal adjustment and personal growth are two main themes in positive adult development research. Personal adjustment refers to how well an individual can master and adapt to their environment, while personal growth refers to having the ability to have deep insight into oneself, others, and the world around them. One other benefit is allowing for changes in social policies to create effective, efficient interventions to help optimize the aging process to as many of our aging generation as possible. In these studies, adults that were older rated higher than these categories then those that were younger, thus supporting that there is indeed a positive development that occurs in adulthood.
Development of the field
Origins of the field
This field stems from several work threads within psychology. Erik Erikson proposed several adult periods. Daniel Levinson also described many "seasons of life." Abraham Maslow proposed an adult hierarchy of needs and Jean Piaget came to agree there was adult postformal stages beyond the stage of formal operations. His earlier theory had located an endpoint to the development of cognitive structures, wherein concluded the Adolescence or adolescent's acquisition of formal operations. John L. Horn found that crystallized intelligence, represented by vocabulary size, increased in adulthood. Robert Kegan combined a Piagetian and an existential-phenomenological approach to creating what he called constructive-developmental psychology. Lawrence Kohlberg found that in early adulthood, some people come to think of moral, ethical, and societal issues in multivariate terms (Systematic stage 11, the first postformal stage). They use multiple relations. During middle adulthood some become principled reasoners about moral issues; for instance, by using abstract principles to relate systems of rights to systems of duties (Meta systematic stage 12, the second postformal stage). Likewise, Cheryl Armon found that by middle adulthood, some people could reason about interpersonal relationships at an order of complexity similar to that described by Lawrence Kohlberg.
Research on positive adult development has grown and expanded upon these early threads and theories in a number of directions. Summaries of some of the initial positive adult development research can be found in the works of Commons, Richards, and Armon, as well as in Alexander and Langer. Four postformal adult stages of development beyond the formal stage have been discovered in a wide variety of domains. The total number of stages across the lifespan now stands at 15. Periods and Seasons have been described.
Many edited books were written on the topic of positive adult development in the 1990s and more recently. In the past decade, researchers have turned to investigating methods to foster positive development in educational as well as organizational settings, rather than by just describing it and/or measuring it. These methods are used in organizational and educational settings. Some use developmentally designed, structured public discourse to address complex public issues. Some of these methods include developing relationships, participating in skill-building opportunities, having educational and career support, participating in civic and social activities, and providing for individual needs. Developmental relationships provide opportunities to support and encourage people in surrounding areas. Participating in skill-building opportunities can promote skill growth and autonomy while providing competence and belonging. Having educational and career support helps individuals form meaningful connections. Participating in civic and social activities encourages involvement in community roles which fosters personal growth. Providing for individual needs provides support for life changes. Methods used to foster positive adult development should focus on letting individuals reach milestones in supportive environments.
Directions of change in positive adult development
To determine whether a particular development in adulthood is positive or not, a value judgment must be made about what kind of change in adult life is optimal or beneficial, and correspondingly what changes in adulthood are harmful. There are several competing standards for what constitutes positive development in adulthood, which can be broadly grouped into five directions; orthogenetic(becoming more hierarchically complex), selective/adaptive (becoming more likely to pass on your genes and for offspring to survive and thrive in an environment that is not ideal), veridical (becoming less biased in your view of the world), eudemonic (becoming happier and healthier), and virtuous (becoming a better person from a particular moral or ethical standpoint).
Studies have been conducted on various components of adult development. One such focus is on the relationship between life experiences and optimism. The relationship between the two is multifaceted. Significant life events can trigger changes in optimism even if there is moderate stability over time. People show resilience by keeping this optimism even through changes and challenges. Although, both positive and negative life events do lead to optimistic fluctuations. The study (Abraham, 2007) supports many personality development theories that similarly show that optimism fluctuates throughout many of life's situations.
Another study (Helson, 2001), presented three positive "paths" a third followed the effects of attitudes of caring for others, which starts in adolescence and then continues into adulthood. Each of the adult individuals follows a path through adult development. These three paths were created using Environmental Mastery (EM) and Personal Growth (PG) scales developed by Carol D. Ryff. The three paths, identified as "Achievers", "Conservers", and "Seekers", were formulated from the patterns that resulted when Ryff's EM and PG tests were administered in the study. The Achievers scored high on both scales. The Conservers scored high on EM and low on PG. The Seekers scored low on EM and high on PG. All three paths were unique but all equally positive. This distinction was concluded to be the result of individual skill and motivation, with each individual's personal action creating personal strengths and personality features. The attributes of emotionality (both positive and negative), processes of identity, and the alterations in self-control across the adulthood years predicted the path classifications. Additionally, each path consisted of a strength profile on the "four criteria of maturity", being competence, generativity, ego development, and wisdom.
Measurements in positive adult development
Assessment of positive adult development can measure quantitative (something that can be counted or measured) or qualitative (things described and cannot be measured in a numerical fashion) change. Measurements of quantitative change assess change on a defined continuous variable, these variables would include such measures as IQ, reaction time, or indicators of personal maturity, authenticity or self-actualization. Quantitative change can be discontinuous if a sudden step-change is in value, or continuous when changes occur gradually and incrementally.
Qualitative change is evidenced by a change in kind, rather than a change in amount, as exemplified by the switch from caterpillar to butterfly. Assessments of qualitative change in adulthood involve assigning written or numerical data to a stage within a defined stage model, according to defined assessment criteria. Researchers have developed a number of such instruments and methods to measure adult development stages, such as themoral judgment interview of Kohlberg, the Berlin Wisdom Interview, the Washington University Sentence Completion Test, the Subject-Object Interview, and the model of hierarchical complexity.
Positive adult development can be measured in multiple domains, including physical health through diet reports, BMI, exercise logs, noticeable and avoidance of risk-taking behaviors. Psychological and emotional well-being can be measured through Satisfaction With Life Scale [SWLS], Life Orientation Test-Revised [LOT-R], reports of positive emotion, and resilience measures. Further development of life skills can be measured through increased self-efficacy, and interpersonal skills, improved decision-making and problem-solving. Other areas of measurement include: ethical behavior- matters such as personal morals, behavioral checklists, and ethical reasoning; healthy relationships- aspects like relationship quality, satisfaction analyses, supportive interactions, and conflict resolution skills; educational attainment- details such as academic records, graduation rates, and levels of certification; occupational engagement-segments regarding career advancement and tracking, employment history, and skill-building; and lastly, civic engagement-channels of volunteering, civic behavior rankings, and community involvement.These can be measured by behavioral observations, developmental milestones, and self-reporting. It is also important to take into consideration the context and culture in which these measurements are taken to ensure accuracy and relevance.
See also
Adult development
Notes
References
Developmental psychology | Positive adult development | [
"Biology"
] | 1,843 | [
"Behavioural sciences",
"Behavior",
"Developmental psychology"
] |
12,108,868 | https://en.wikipedia.org/wiki/Lapachol | Lapachol is a natural phenolic compound isolated from the bark of the lapacho tree. This tree is known botanically as Handroanthus impetiginosus, but was formerly known by various other botanical names such as Tabebuia avellanedae. Lapachol is also found in other species of Handroanthus.
Lapachol is usually encountered as a yellow, skin-irritating powder from wood. Chemically, it is a derivative of vitamin K.
Once studied as a possible treatment for some types of cancer, it is now considered too toxic for use.
See also
§Hooker-Oxidation§
References
1,4-Naphthoquinones
Hydroxynaphthoquinones
Plant toxins
Terpeno-phenolic compounds | Lapachol | [
"Chemistry"
] | 160 | [
"Chemical ecology",
"Plant toxins"
] |
12,109,800 | https://en.wikipedia.org/wiki/CoWord | CoWord is a software add-on to Microsoft Word to enable multiple users to edit the same document over the Internet with MS Word. It is a part of the CoOffice suite of collaboration tools for Microsoft Office.
CoWord can be considered as a collaborative real-time editor, with the editor being MS Word (which is not distributed with CoWord). To use CoWord, users need to supply their own copies of MS Word.
As of August 2010, CoWord has become CodoxWord, released by CodoxWare.
Technology
One of the main challenges in building collaborative real-time editors is in concurrency control. The concurrency control technology used by CoWord is Operational transformation. Operational transformation (OT) can incorporate concurrent changes made to replicas of the same document. This means systems built with OT allow multiple users to make concurrent changes to the document, and all changes will be incorporated. Other known systems based on Operational transformation are: ACE, Gobby, and Subethaedit.
In CoWord, OT is implemented in a module called Generic Collaborative Engine (GCE). GCE is also provided as a library package, allowing other developers to create real-time collaborative editing systems without having to implement OT.
External links
CodoxWord Home page
Adaption technology used build CoWord
The operational transformation algorithm used by CoWord
OTFAQ: Operational Transformation Frequently Asked Questions and Answers
Presentation of CoWord technology to Microsoft Research (Video)
CodoxWord and CodoxWare
References
Microsoft Office
Collaborative real-time editors | CoWord | [
"Technology"
] | 307 | [
"Collaborative real-time editors"
] |
12,110,212 | https://en.wikipedia.org/wiki/DNA%20database | A DNA database or DNA databank is a database of DNA profiles which can be used in the analysis of genetic diseases, genetic fingerprinting for criminology, or genetic genealogy. DNA databases may be public or private, the largest ones being national DNA databases.
DNA databases are often employed in forensic investigations. When a match is made from a national DNA database to link a crime scene to a person whose DNA profile is stored on a database, that link is often referred to as a cold hit. A cold hit is of particular value in linking a specific person to a crime scene, but is of less evidential value than a DNA match made without the use of a DNA database. Research shows that DNA databases of criminal offenders reduce crime rates.
Types
Forensic
A forensic database is a centralized DNA database for storing DNA profiles of individuals that enables searching and comparing of DNA samples collected from a crime scene against stored profiles. The most important function of the forensic database is to produce matches between the suspected individual and crime scene bio-markers, and then provides evidence to support criminal investigations, and also leads to identify potential suspects in the criminal investigation. Majority of the National DNA databases are used for forensic purposes.
The Interpol DNA database is used in criminal investigations. Interpol maintains an automated DNA database called DNA Gateway that contains DNA profiles submitted by member countries collected from crime scenes, missing persons, and unidentified bodies. The DNA Gateway was established in 2002, and at the end of 2013, it had more than 140,000 DNA profiles from 69 member countries. Unlike other DNA databases, DNA Gateway is only used for information sharing and comparison, it does not link a DNA profile to any individual, and the physical or psychological conditions of an individual are not included in the database.
Genealogical
A national or forensic DNA database is not available for non-police purposes. DNA profiles can also be used for genealogical purposes, so that a separate genetic genealogy database needs to be created that stores DNA profiles of genealogical DNA test results. GenBank is a public genetic genealogy database that stores genome sequences submitted by many genetic genealogists. Until now, GenBank has contained large number of DNA sequences gained from more than 140,000 registered organizations, and is updated every day to ensure a uniform and comprehensive collection of sequence information. These databases are mainly obtained from individual laboratories or large-scale sequencing projects. The files stored in GenBank are divided into different groups, such as BCT (bacterial), VRL (viruses), PRI (primates)...etc. People can access GenBank from NCBI's retrieval system, and then use “BLAST” function to identify a certain sequence within the GenBank or to find the similarities between two sequences.
Medical
A medical DNA database is a DNA database of medically relevant genetic variations. It collects an individual's DNA which can reflect their medical records and lifestyle details. Through recording DNA profiles, scientists may find out the interactions between the genetic environment and occurrence of certain diseases (such as cardiovascular disease or cancer), and thus finding some new drugs or effective treatments in controlling these diseases. It is often collaborated with the National Health Service.
National
A national DNA database is a DNA database maintained by the government for storing DNA profiles of its population. Each DNA profile based on PCR uses STR (Short Tandem Repeats) analysis. They are generally used for forensic purposes, including searching and matching DNA profiles of potential criminal suspects.
In 2009 Interpol reported 54 police national DNA databases in the world and 26 more countries planned to start one. In Europe Interpol reported there were 31 national DNA databases and six more planned. The European Network of Forensic Science Institutes (ENFSI) DNA working group made 33 recommendations in 2014 for DNA database management and guidelines for auditing DNA databases. Other countries have adopted privately developed DNA databases, such as Qatar, which has adopted Bode dbSEARCH.
Typically, a tiny subset of the individual's genome is sampled from 13 or 16 regions that have high individuation.
United Kingdom
The first national DNA database in the United Kingdom was established in April 1995, called National DNA Database (NDNAD). By 2006, it contained 2.7 million DNA profiles (about 5.2% of the UK population), as well as other information from individuals and crime scenes. in 2020 it had 6.6 million profiles (5.6 million individuals excluding duplicates). The information is stored in the form of a digital code, which is based on the nomenclature of each STR. In 1995 the database originally had 6 STR markers for each profile, from 1999 10 markers, and from 2014, 16 core markers and a gender identifier. Scotland has used 21 STR loci, two Y-DNA markers and a gender identifier since 2014. In the UK, police have wide-ranging powers to take DNA samples and retain them if the subject is convicted of a recordable offence. As the large amount of DNA profiles which have been stored in NDNAD, "cold hits" may happen during the DNA matching, which means finding an unexpected match between an individual's DNA profile and an unsolved crime-scene DNA profile. This can introduce a new suspect into the investigation, thus helping to solve the old cases.
In England and Wales, anyone arrested on suspicion of a recordable offence must submit a DNA sample, the profile of which is then stored on the DNA database. Those not charged or not found guilty have their DNA data deleted within a specified period of time. In Scotland, the law similarly requires the DNA profiles of most people who are acquitted be removed from the database.
New Zealand
New Zealand was the second country to set up a DNA database. In 2019 The New Zealand DNA Profile Databank held 40,000 DNA profiles and 200,000 samples.
United States
The United States national DNA database is called Combined DNA Index System (CODIS). It is maintained at three levels: national, state and local. Each level implemented its own DNA index system. The national DNA index system (NDIS) allows DNA profiles to be exchanged and compared between participated laboratories nationally. Each state DNA index system (SDIS) allows DNA profiles to be exchanged and compared between the laboratories of various states and the local DNA index system (LDIS) allows DNA profiles collected at local sites and uploaded to SDIS and NDIS.
CODIS software integrates and connects all the DNA index systems at the three levels. CODIS is installed on each participating laboratory site and uses a standalone network known as Criminal Justice Information Systems Wide Area Network (CJIS WAN) to connect to other laboratories. In order to decrease the number of irrelevant matches at NDIS, the Convicted Offender Index requires all 13 CODIS STRs to be present for a profile upload. Forensic profiles only require 10 of the STRs to be present for an upload.
As of 2011, over 9 million records were held within CODIS. As of March 2011, 361,176 forensic profiles and 9,404,747 offender profiles have been accumulated, making it the largest DNA database in the world. As of the same date, CODIS has produced over 138,700 matches to requests, assisting in more than 133,400 investigations.
The growing public approval of DNA databases has seen the creation and expansion of many states' own DNA databases. Political measures such as California Proposition 69 (2004), which increased the scope of the DNA database, have already met with a significant increase in numbers of investigations aided. Forty-nine states in the USA, all apart from Idaho, store DNA profiles of violent offenders, and many also store profiles of suspects. A 2017 study showed that DNA databases in U.S. states "deter crime by profiled offenders, reduce crime rates, and are more cost-effective than traditional law enforcement tools".
CODIS is also used to help find missing persons and identify human remains. It is connected to the National Missing Persons DNA Database; samples provided by family members are sequenced by the University of North Texas Center for Human Identification, which also runs the National Missing and Unidentified Persons System. UNTCHI can sequence both nuclear and mitochondrial DNA.
The Department of Defense maintains a DNA database to identify the remains of service members. The Department of Defense Serum Repository maintains more than 50,000,000 records, primarily to assist in the identification of human remains. Submission of DNA samples is mandatory for US servicemen, but the database also includes information on military dependents. The National Defense Authorization Act of 2003 provided a means for federal courts or military judges to order the use of the DNA information collected to be made available for the purpose of investigation or prosecution of a felony, or any sexual offense, for which no other source of DNA information is reasonably available.
Australia
The Australian national DNA database is called the National Criminal Investigation DNA Database (NCIDD). By July 2018, it contained 837,000+ DNA profiles. The database used nine STR loci and a sex gene for analysis, and this was increased to 18 core markers in 2013. NCIDD combines all forensic data, including DNA profiles, advanced bio-metrics or cold cases.
Canada
The Canadian national DNA database is called the National DNA Data Bank (NDDB) which was established in 1998 but first used in 2000. The legislation that Parliament enacted to govern the use of this technology within the criminal justice system has been found by Canadian courts to be respectful of the constitutional and privacy rights of suspects, and of persons found guilty of designated offences.
On December 11, 1999, The Canadian Government agreed upon the DNA Identification Act. This would allow a Canadian DNA data bank to be created and amended for the criminal code. This provides a mechanism for judges to request the offender to provide blood, buccal swabs, or hair samples from DNA profiles. This legislation became official on June 29, 2000. Canadian police has been using forensic DNA evidence for over a decade. It has become one of the most powerful tools available to law enforcement agencies for the administration of justice.
NDDB consists of two indexes: the Convicted Offender Index (COI) and National Crime Scene Index (CSI-nat). There is also the Local Crime Scene Index (CSI-loc) which is maintained by local laboratories but not NDDB as local DNA profiles do not meet NDDB collection criteria. Another National Crime Scene Index (CSI-nat) is a collection of three labs operated by Royal Canadian Mounted Police (RCMP), Laboratory Sciences Judiciary Medicine Legal (LSJML) and Center of Forensic Sciences (CFS).
Dubai
In 2017 Dubai announced an initiative called Dubai 10X which was planned to create 'disruptive innovation' into the country. One of the projects in this initiative was a DNA database that would collect the genomes of all 3 million citizens of the country over a 10-year period. It was intended to use the data base for finding genetic causes of diseases and creating personalised medical treatments.
Germany
Germany set up its DNA database for the German Federal Police (BKA) in 1998.
In late 2010, the database contained DNA profiles of over 700,000 individuals and in September 2016 it contained 1,162,304 entries. On 23 May 2011 in the "Stop the DNA Collection Frenzy!" campaign various civil rights and data protection organizations handed an open letter to the German minister of justice Sabine Leutheusser-Schnarrenberger asking her to take action in order to stop the "preventive expansion of DNA data-collection" and the "preemptive use of mere suspicions and of the state apparatus against individuals" and to cancel projects of international exchange of DNA data at the European and transatlantic level.
Israel
The Israeli national DNA database is called the Israel Police DNA Index System (IPDIS) which was established in 2007, and has a collection of more than 135,000 DNA profiles. The collection includes DNA profiles from suspected and accused persons and convicted offenders. The Israeli database also include an “elimination bank” of profiles from laboratory staff and other police personnel who may have contact with the forensic evidence in the course of their work.
In order to handle the high throughput processing and analysis of DNA samples from FTA cards, the Israeli Police DNA database has established a semi-automated program LIMS, which enables a small number of police to finish processing a large number of samples in a relatively small period of time, and it is also responsible for the future tracking of samples.
Kuwait
The Kuwaiti government passed a law in July 2015 requiring all citizens and permanent residents (4.2 million people) to have their DNA taken for a national database. The reason for this law was security concerns after the ISIS suicide bombing of the Imam Sadiq mosque. They planned to finish collecting the DNA by September 2016 which outside observers thought was optimistic. In October 2017 the Kuwait constitutional court struck down the law saying it was an invasion of personal privacy and the project was cancelled.
Brazil
In 1998, the Forensic DNA Research Institute of Federal District Civil Police created DNA databases of sexual assault evidence. In 2012, Brazil approved a national law establishing DNA databases at state and national levels regarding DNA typing of individuals convicted of violent crimes. Following the decree of the Presidency of the Republic of Brazil in 2013, which regulates the 2012 law, Brazil began using CODIS in addition to the DNA databases of sexual assault evidence to solve sexual assault crimes in Brazil.
France
France set up the DNA database called FNAEG in 1998. By December 2009, there were 1.27 million profiles on FNAEG.
Russia
In Russia, scientific DNA testing is being actively carried out in order to study the genetic diversity of the peoples of Russia in the framework of the state task - to learn from DNA to determine the probable territory of human origin based on data on the majority of the peoples of the country. On June 16, 2017, the Council of Ministers of the Union State of Belarus and Russia adopted Resolution No. 26, in which it approved the scientific and technical program of the Union State "Development of innovative genogeographic and genomic technologies for identification of personality and individual characteristics of a person based on the study of gene pools of the regions of the Union State" (DNA - identification).
Within the framework of this program, it is also planned to include the peoples of neighboring countries, which are the main source of migration, into the genogeographic study on the basis of existing collections.
In accordance with the Federal Law of December 3, 2008 No. 242-FZ "On state genomic registration in the Russian Federation", voluntary state genomic registration of citizens of the Russian Federation, as well as foreign citizens and stateless persons living or temporarily staying in the territory of the Russian Federation on the basis of a written application and on a paid basis. Genomic information obtained as a result of state genomic registration is used, among other things, for the purpose of establishing family relationships of wanted (identified) persons. The form of keeping records of data on genomic registration of citizens is the Federal Genomic Information Database (FBDGI).
Articles 10 and 11 of the Federal Law of July 27, 2006 No. 152-FZ "On Personal Data" provide that the processing of special categories of personal data relating to race, nationality, political views, religious or philosophical beliefs, health status, intimate life is allowed if it is necessary in connection with the implementation of international agreements of the Russian Federation on readmission and is carried out in accordance with the legislation of the Russian Federation on citizenship of the Russian Federation. Information characterizing the physiological and biological characteristics of a person, on the basis of which it is possible to establish his identity (biometric personal data), can be processed without the consent of the subject of personal data in connection with the implementation of international agreements of the Russian Federation on readmission, administration of justice and execution of judicial acts, compulsory state fingerprinting registration, as well as in cases stipulated by the legislation of the Russian Federation on defense, security, anti-terrorism, transport security, anti-corruption, operational investigative activities, public service, as well as in cases stipulated by the criminal-executive legislation of Russia, the legislation of Russia on the procedure for leaving the Russian Federation and entering the Russian Federation, citizenship of the Russian Federation and notaries.
Other European countries
In comparison with the other European countries, The Netherlands is the largest collector of DNA profiles of its citizens. At this moment the DNA databank at the Netherlands Forensic Institute contains the DNA profiles of over 316,000 Dutch citizens.
Contrary to the situation in most other European countries, the Dutch police have wide-ranging powers to take and retain DNA samples if a subject is convicted of a recordable offence, except when the conviction only involves paying a fine. If a subject refuses, for example because of privacy concerns, the Dutch police will use force.
In Sweden, only the DNA profiles of criminals who have spent more than two years in prison are stored. In Norway and Germany, court orders are required, and are only available, respectively, for serious offenders and for those convicted of certain offences and who are likely to reoffend. Austria started a criminal DNA database in 1997 and Italy also set one up in 2016 Switzerland started a temporary criminal DNA database in 2000 and confirmed it in law in 2005.
In 2005 the incoming Portuguese government proposed to introduce a DNA database of the entire population of Portugal. However, after informed debate including opinion from the Portuguese Ethics Council the database introduced was of just the criminal population.
Genuity Science (formerly Genomics Medicine Ireland) is an Irish life sciences company that was founded in 2015 to create a scientific platform to perform genomic studies and generate new disease prevention strategies and treatments. The company was founded by a group of life science entrepreneurs, investors and researchers and its scientific platform is based on work by Amgen’s Icelandic subsidiary, deCODE genetics, which has pioneered genomic population health studies. The company is building a genomic database which will include data from about 10 per cent of the Irish population, including patients with various diseases and healthy people. The idea of a private company owning public DNA data has raised concerns, with an Irish Times editorial stating: "To date, Ireland seems to have adopted an entirely commercial approach to genomic medicine. This approach places at risk the free availability of genomic data for scientific research that could benefit patients." The paper's editorial pointed out that this is in stark contrast to the approach the U.K. has taken, which is the publicly and charitably funded 100,000 Genomes Project being carried out by Genomics England.
China
By 2020, Chinese police had collected 80 million DNA profiles. There have been concerns that China may be using DNA data not just for crime solving, but for tracking activists, including Uyghurs.
Chinese have begun a $9 billion program for genetic science studying, Fire-Eye has DNA labs in over 20 countries.
India
India announced it will launch its genomic database by fall 2019. In the first phase of "Genome India" the genomic data of 10,000 Indians will be catalogued. The Department of Biotechnology (DBT) has initiated the project. The first private DNA bank in India is in Lucknow - the capital of Indian State Uttar Pradesh. Unlike a research center, this is available for Public to store their DNA by paying a minimum amount and four drops of blood.
Corporate
Ancestry was reported to have collected 14 million DNA samples as of November 2018.
23andme's DNA database contained genetic information of over nine million people worldwide by 2019. The company explores selling the "anonymous aggregated genetic data" to other researchers and pharmaceutical companies for research purposes if patients give their consent. Ahmad Hariri, professor of psychology and neuroscience at Duke University who has been using 23andMe in his research since 2009 states that the most important aspect of the company's new service is that it makes genetic research accessible and relatively cheap for scientists. A study that identified 15 genome sites linked to depression in 23andMe's database lead to a surge in demands to access the repository with 23andMe fielding nearly 20 requests to access the depression data in the two weeks after publication of the paper.
My Heritage said their database had 2.5 million profiles in 2019.
Family Tree DNA was reported they had about two million people in their database in 2019.
Fire-Eye
Compression
DNA databases occupy more storage when compared to other non DNA databases due to the enormous size of each DNA sequence. Every year DNA databases grow exponentially. This poses a major challenge to the storage, data transfer, retrieval and search of these databases. To address these challenges DNA databases are compressed to save storage space and bandwidth during the data transfers. They are decompressed during search and retrieval. Various compression algorithms are used to compress and decompress. The efficiency of any compression algorithm depends how well and fast it compresses and decompresses, which is generally measured in compression ratio. The greater the compression ratio, the better the efficiency of an algorithm. At the same time, the speed of compression and decompression are also considered for evaluation.
DNA sequences contain palindromic repetitions of A, C, T, G. Compression of these sequences involve locating and encoding these repetitions and decoding them during decompression.
Some approaches used to encode and decode are:
Huffman Encoding
Adaptive Huffman Encoding
Arithmetic coding
Arithmetic coding
Context tree weighting (CTW) method
The compression algorithms listed below may use one of the above encoding approaches to compress and decompress DNA database
Compression using Redundancy of DNA sets (COMRAD)
Relative Lempel-Ziv (RLZ)
GenCompress
BioCompress
DNACompress
CTW+LZ
In 2012, a team of scientists from Johns Hopkins University published the first genetic compression algorithm that does not rely on external genetic databases for compression. HAPZIPPER was tailored for HapMap data and achieves over 20-fold compression (95% reduction in file size), providing 2- to 4-fold better compression much faster than leading general-purpose compression utilities.
Genomic sequence compression algorithms, also known as DNA sequence compressors, explore the fact that DNA sequences have characteristic properties, such as inverted repeats. The most successful compressors are XM and GeCo. For eukaryotes XM is slightly better in compression ratio, though for sequences larger than 100 MB its computational requirements are impractical.
Medicine
Many countries collect newborn blood samples to screen for diseases mainly with a genetic basis. Mainly these are destroyed soon after testing. In some countries the dried blood (and the DNA) is retained for later testing.
In Denmark the Danish Newborn Screening Biobank at Statens Serum Institut keeps a blood sample from people born after 1981. The purpose is to test for phenylketonuria and other diseases. However, it is also used for DNA profiling to identify deceased and suspected criminals. Parents can request that the blood sample of their newborn be destroyed after the result of the test is known.
Privacy issues
Critics of DNA databases warn that the various uses of the technology can pose a threat to individual civil liberties. Personal information included in genetic material, such as markers that identify various genetic diseases, physical and behavioral traits, could be used for discriminatory profiling and its collection may constitute an invasion of privacy. Also, DNA can be used to establish paternity and whether or not a child is adopted. Nowadays, the privacy and security issues of DNA database has caused huge attention. Some people are afraid that their personal DNA information will be let out easily, others may define their DNA profiles recording in the Databases as a sense of "criminal", and being falsely accused in a crime can lead to having a "criminal" record for the rest of their lives.
UK laws in 2001 and 2003 allowed DNA profiles to be taken immediately after a person was arrested and kept in a Database even if the suspect was later acquitted. In response to public unease at these provisions, the UK later changed this by passing the Protection of Freedoms Act 2012 which required that those suspects not charged or found not guilty would have their DNA data deleted from the Database.
In European countries which have established a DNA database, there are some measures which are being used to protect the privacy of individuals, more specifically, some criteria to help removing the DNA profiles from the databases. Among the 22 European countries which have been analyzed, most of the countries will record the DNA profiles of suspects or those who have committed serious crimes. For some countries (like Belgium and France) may remove the criminal's profile after 30–40 years, because these “criminal investigation” database are no longer needed. Most of the countries will delete the suspect's profile after they are acquitted...etc. All the countries have a completed legislation to largely avoid the privacy issues which may occur during the use of DNA database. Public discussion around the introduction of advanced forensic techniques (such as genetic genealogy using public genealogy databases and DNA phenotyping approaches) has been limited, disjointed, and unfocused, and raises issues of privacy and consent that may warrant additional legal protections to be established.
Privacy issues surrounding DNA databases not only means privacy is threatened in collecting and analyzing DNA samples, it also exists in protecting and storing this important personal information. As the DNA profiles can be stored indefinitely in DNA database, it has raised concerns that these DNA samples can be used for new and unidentified purposes. With the increase of the users who access the DNA database, people are worried about their information being let out or shared inappropriately, for example, their DNA profile may be shared with others such as law enforcement agencies or countries without individual consent.
The application of DNA databases have been expanded into two controversial areas: arrestees and familial searching. An arrestee is a person arrested for a crime and who has not yet been convicted for that offense. Currently, 21 states in the United States have passed legislation that allows law enforcement to take DNA from an arrestee and enter it into the state's CODIS DNA database to see if that person has a criminal record or can be linked to any unsolved crimes. In familial searching, the DNA database is used to look for partial matches that would be expected between close family members. This technology can be used to link crimes to the family members of suspects and thereby help identify a suspect when the perpetrator has no DNA sample in the database.
Furthermore, DNA databases could fall into the wrong hands due to data breaches or data sharing.
DNA collection and human rights
In a judgement in December 2008, the European Court of Human Rights ruled that two British men should not have had their DNA and fingerprints retained by police saying that retention "could not be regarded as necessary in a democratic society".
The DNA fingerprinting pioneer Professor Sir Alec Jeffreys condemned UK government plans to keep the genetic details of hundreds of thousands of innocent people in England and Wales for up to 12 years. Jeffreys said he was "disappointed" with the proposals, which came after a European court ruled that the current policy breaches people's right to privacy. Jefferys said "It seems to be as about as minimal a response to the European court of human rights judgment as one could conceive. There is a presumption not of innocence but of future guilt here … which I find very disturbing indeed".
Effects on crime
A 2021 study found that registration of Danish criminal offenders in a DNA database substantially reduced the probability of re-offending, as well as increased the likelihood that re-offenders were identified if they committed future crimes.
A 2017 study in the American Economic Journal: Applied Economics showed that databases of criminal offenders' DNA profiles in US states "deter crime by profiled offenders, reduce crime rates, and are more cost-effective than traditional law enforcement tools."
Monozygotic twins
Monozygotic twins share around 99.99% of their DNA, while other siblings share around 50%. Some next generation sequencing tools are capable of detecting rare de novo mutations in only one of the twins (detectable in rare single nucleotide polymorphisms). Most DNA testing tools would not detect these rare SNPs in most twins.
Each person's DNA is unique to them to the slight exception of identical (monozygotic and monospermotic) twins, who start out from the identical genetic line of DNA but during the twinning event have incredibly small mutations which can be detected now (for all intents and purposes, compared to all other humans and even to theoretical "clones, [who would not share the same uterus nor experience the same mutations pre-twinning event]" identical twins have more identical DNA than is probably possible to achieve between any other two humans). Tiny differences between identical twins can now (2014) be detected by next generation sequencing. For current fiscally available testing, "identical" twins cannot be easily differentiated by the most common DNA testing, but it has been shown to be possible. While other siblings (including fraternal twins) share about 50% of their DNA, monozygotic twins share virtually 99.99%. Beyond these more recently discovered twinning-event mutation disparities, since 2008 it has been known that people who are identical twins also each have their own set of copy number variants, which can be thought of as the number of copies they each personally exhibit for certain sections of DNA.
See also
Combined DNA Index System (CODIS)
DNA profiling
Forensic Science Service
Government databases
LGC Forensics
UK National DNA Database
References
Biological databases
Government databases
Privacy
Forensic databases
Forensic genetics | DNA database | [
"Biology"
] | 6,003 | [
"Bioinformatics",
"Biological databases"
] |
12,110,323 | https://en.wikipedia.org/wiki/Flood%20control%20channel | Flood control channels are large and empty basins where surface water can flow through but is not retained (except during flooding), or dry channels that run below the street levels of some larger cities, so that if a flash flood occurs the excess water can drain out along these channels into a river or other bodies of water. Flood channels are sometimes built on the former courses of natural waterways as a way to reduce flooding.
Channelization of this sort was commonly done in the 1960s, but is now often being undone, with "rechannelization" through meandering, vegetated, porous paths. This is because channellizing the flow in a concrete chute often made flooding worse.
Water levels during a flood tend to rise, then fall, exponentially. The peak flood level occurs as a very steep, short spike; a quick spurt of water. Anything that slows the surface runoff (marshes, meanders, vegetation, porous materials, turbulent flow, the river spreading over a floodplain) will slow some of the flow more than other parts, spreading the flow over time and blunting the spike. Even slightly blunting the spike significantly decreases the peak flood level. Generally, the higher the peak flood level, the more flood damage is done. Straight, clear, smooth concrete-walled channels speed up flow, and are therefore likely to make flooding downstream worse. Modern flood control seeks to "slow the flow", and deliberately flood some low-lying areas, ideally vegetated, to act as sponges, letting them drain again as the floodwaters go down.
Levees
Flood control channels are not to be confused with watercourses which are simply confined between levees. These structures may be made entirely of concrete, with concrete sides and an exposed bottom, with riprap sides and an exposed bottom, or completely unlined. They often contain grade control sills or weirs to prevent erosion and maintain a level streambed.
Distribution
By definition, flood control channels range from the size of a street gutter to a few hundred or even a few thousand feet wide in some rare cases. Flood control channels are found in most heavily developed areas in the world. One city with many of these channels is Los Angeles, as they became mandatory with the passage of the Flood Control Act of 1941 passed in the wake of the Los Angeles Flood of 1938.
See also
Nullah
Drop structure
Urban runoff
Weir
Levee
References
External links
LA River Flood Control Channel
Guadalupe River Flood Control Channel
Flood control
Rivers | Flood control channel | [
"Chemistry",
"Engineering"
] | 509 | [
"Flood control",
"Environmental engineering"
] |
12,110,590 | https://en.wikipedia.org/wiki/HDR%2C%20Inc. | HDR, Inc. is an American design and engineering company based in Omaha, Nebraska.
History
In 1917, the Henningson Engineering Company started as a civil engineering firm in Omaha, where HDR's headquarters remain today. Willard Richardson and Charles W. "Chuck" Durham joined the firm in 1939 as interns. Circa 1950, Richardson and Durham had purchased shares in the firm, and it became known as Henningson, Durham and Richardson, Inc.
The company's first project was designing a power station for the city of Ogallala, Nebraska. Similar projects followed as the firm built water, sewer, electric, and road systems for cities and towns throughout the Midwestern United States, emerging from frontier status.
In 1983, Bouygues SA, France's largest construction company, purchased HDR for $60 million. An employee group bought back HDR in 1996 for $55 million. The company has since grown from 1,100 employees to over 12,000.
Acquisitions
Since the employee buyout in 1996 from the French conglomerate Bouygues, HDR has acquired over 60 firms around the world. In February 2011, HDR acquired Cooper Medical, an Oklahoma City, Oklahoma, based firm providing integrated design and construction services for healthcare facilities throughout the U.S. The new alliance, HDR Cooper Medical, will provide a service design and construction delivery model to healthcare clients. In February 2011, HDR acquired Schiff Associates, a recognized leader in corrosion engineering headquartered in Claremont, California, with offices in Houston, Las Vegas, and San Diego.
In January 2011, HDR acquired HydroQual, Inc., which specializes in water resource management. Based in Mahwah, N.J., HydroQual had nine offices in New Jersey, New York, Massachusetts, Florida, Utah and Dubai. HydroQual is now conducting business as HDR. Also in January 2011, HDR acquired Amnis Engineering Ltd., based in Vancouver, British Columbia. The firm provides engineering and consulting services in British Columbia and a number of international locations for hydropower and water resources infrastructure.
In March 2013, HDR acquired TMK Architekten • Ingenieure, a German healthcare architecture firm. The merged company was the hub for HDR's healthcare and science design programs in Europe. In 2023, HDR sold its subsidiary HDR GmbH to a small group of employees in the country. The new operating company is Telluride Architektur GmbH.
In April 2013, HDR acquired Salva Resources, a global provider of technical and commercial services for mining exploration and investment in Brisbane, Australia.
In July 2013, HDR acquired the business and assets of Sharon Greene + Associates, a firm specializing in transportation economics and financial analysis.
In November 2013, HDR acquired Rice Daubney Architects, a firm in Sydney, Australia. The merged company is the hub for HDR's healthcare, defence, retail, and commercial work in Australia and HDR's retail and commercial work throughout the globe.
In January 2015, HDR acquired the assets of MEI, LLC, a liquid natural gas engineering and consulting firm based in Pooler, Georgia.
In July, 2015, HDR acquired CEI Architecture of Vancouver, British Columbia, an architectural, planning and interior design consultant.
In September, 2017, HDR acquired long-time partner, Maintenance Design Group, a firm specializing in the planning and design of vehicle and fleet operations and maintenance facilities. HDR sought to add MDG's strengths in facility planning and design to complement its asset life-cycle approach to infrastructure development.
In 2018, HDR expanded its water resources services by acquiring the assets of David Ford Consulting Engineers, a firm based in Sacramento, California. The firm specializes in water hydraulics, flood risk analysis, reservoir systems and operations, water resource planning and hydro-economics.
Hurley Palmer Flatt
In July 2019, HDR expanded its footprint in Europe and Asia by acquiring the British firm Hurley Palmer Flatt, as well as its subsidiaries; Hurley Palmer Flatt rebranded to HDR in early 2022.
Hurley Palmer Flatt was a multi-disciplinary engineering consultancy based in London. It provided mechanical and electrical engineering consultancy and associated services. It was established in 1968 in the UK by John Hurley as a building services consultancy. It expanded into a global company operating in Dubai, India, Australia, Singapore and the US, engaging in both public and private sector development across various fields.
In 2009 Hurley Palmer Flatt acquired ATCO Consulting, expanding its reach in Scotland.
In 2014 it acquired London-based mechanical and engineering firm Andrew Reid and Partners (AR&P) and took a majority controlling share of the business. AR&P had been established in 1970 by Andrew Reid. Its core services included diagnostic assessments of under-performing buildings and the management or independent validation of building engineering services commissioning. Its work in commissioning began at the Barbican Arts Centre, through all 14 phases of London's Broadgate development to the present day including the 750,000ft2 headquarters for UBS at 5 Broadgate in London. From the late 1990s, AR&P successfully commissioned data centres for several of the world most successful brands. Its design engineers were involved in work at The National Gallery from the mid-1980s when the company designed the building services for the new Sainsbury Wing, and have been involved in other museums and galleries including Dulwich Picture Gallery, the National Maritime Museum and the Imperial War Museum.
In 2016, Hurley Palmer Flatt acquired a majority share in the civil and structural engineering business, Bradbrook Consulting, which had UK offices in London, Kingston, Watford, and Manchester, and a Dubai office.
In 2016, the company moved its central London office to 240 Blackfriars at the South Bank Tower on a 10-year lease as part of its expansion plan.
Notable Hurley Palmer Flatt projects
Sea Containers House, UK
Taymouth Castle, UK
195-197 Kings Road, UK, for Martins Properties
Weston Library, Oxford University, UK, shortlisted for the 2016 Stirling Prize.
Renovated Archive & Book Storage Facility, Bodleian Library, Oxford University, UK
Aberdeen Exhibition And Conference Centre Energy Centre, UK, for Henry Boot Developments
Singapore Changi Airport, Singapore
New Data Centre Australian Securities Exchange, Australia
1 Knightsbridge, for JP Morgan, UK
Croydon Data Centre, for Morgan Stanley, UK
Dundee railway station, UK
10 Upper Bank Street & The Zig Zag Building, Victoria, for Deutsche Bank, UK
131 Sloane Street, for Marshall Wace, UK
Notable Andrew Reid and Partners projects
The National Gallery
The Imperial War Museum
National Maritime Museum
Broadgate development, London
Deutsche Bank
Mary Rose Trust
Ashmolean Museum
University of Greenwich
Guildhall School of Music
Hurley Palmer Flatt awards and recognition
Number 34 in Top 150 Consultants 2016 by Building
View58 (58 Victoria Embankment) was Highly Commended the 2016 Property Awards in the Sustainability category
Nominated for the Training Initiative of the Year at the Consultancy and Engineering Awards 2016
Weston Library won AJ100 Building of the Year
Weston Library also won the RIBA National Award 2016, RIBA South Award 2016 and the RIBA South Building of the Year 2016
Winner in the Affordable Housing category at the Scottish Design Awards 2008 for Fyne Homes & CP Architects Gigha project in West Scotland
Nominated for the CIBSE Employer of the Year 2017 Award
Number 24 in Top 150 Consultants 2019 by Building
In June 2021, HDR acquired WKE, a multimodal transportation engineering firm based in Santa Ana, California. Their practice complements HDR's collaborative, full life cycle approach to infrastructure development and delivery of critical transportation programs in the Southwest region of the United States.
In September 2021, HDR acquired WRECO, a leader in innovative engineering solutions for communities throughout California based in Walnut Creek. The addition expands transportation and water resources services in the region.
In February 2022, HDR acquired SPF Water Engineering, a water, wastewater and hydrogeologic consulting firm based in Boise, Idaho. As part of the asset acquisition, SPF includes MDS Drafting, which provides value-added services in BIM.
Controversies
Prison design
HDR Architecture's jail and prison design projects have faced criticism from advocates in communities where the projects are proposed. In 2019, advocates in Travis County, TX opposed the construction of a new women's jail, arguing the resources would be better spent on programs to address concerns like addiction and mental health. Following community pressure, Travis County commissioners indefinitely paused HDR's $4.6 million contract to design the women's jail in June 2021. HDR also faced criticism from advocates in Massachusetts after being selected in 2021 to design a new women's prison for the Massachusetts Department of Correction. Advocates opposed all new prison construction and particularly argued against HDR's proposed “trauma-informed” design, saying it was not possible in a prison environment.
Monitoring of activists
In August 2021, a Motherboard story detailed HDR's monitoring services provided to government agencies conducting controversial projects. The report highlighted HDR's "corporate counterinsurgency" work, especially social media monitoring, to anticipate and disrupt public opposition to projects, including highways built through sacred Indigenous sites and prison and jail construction.
Awards
In 2018, the American Council of Engineering Companies awarded the Grand Conceptor Award to HDR and joint venture partner WSP USA for the design and construction of a new roadway within the steel-arch Bayonne Bridge—64 feet above an existing highway it was to replace. The Grand Conceptor Award signifies the year's most outstanding engineering achievement. The recognition marked HDR's fourth Grand Conceptor in the company's 100-year history, and the second time that HDR received the award two years in a row. In 2017, the State Route 520 floating bridge earned the American Council of Engineering Companies' Grand Conceptor Award.
HDR also won back-to-back Grand Conceptor Awards in 2010 and 2011. The 2011 award winner was the Hoover Dam Bypass. HDR was the project manager for this project. The Hoover Dam Bypass won several other industry awards. The 2010 winner was the Gills Onions Advanced Energy Recovery System in Oxnard, California, which uses onion waste to produce renewable energy.
Miscellaneous
HDR has worked on projects in all 50 U.S. states and in 60 countries, including notable projects such as the Hoover Dam Bypass, Alexander T. Augusta Military Medical Center, and Roslin Institute building. The firm employs over 12,000 professionals and represents hundreds of disciplines in various markets. HDR is the 5th largest employee-owned company in the United States with revenues of $2.8 billion in 2022. Engineering News-Record ranked HDR as the 6th largest design firm in the United States in 2023.
References
Design companies established in 1917
Architecture firms based in Nebraska
Construction and civil engineering companies of the United States
Engineering consulting firms of the United States
International engineering consulting firms
Companies based in Omaha, Nebraska
1917 establishments in Nebraska
Construction and civil engineering companies established in 1917
Business services companies established in 1917 | HDR, Inc. | [
"Engineering"
] | 2,233 | [
"Engineering consulting firms",
"International engineering consulting firms"
] |
12,111,508 | https://en.wikipedia.org/wiki/Type%20V%20collagen | Type V collagen is a form of fibrillar collagen associated with classical Ehlers-Danlos syndrome. It is found within the dermal/epidermal junction, placental tissues, as well as in association with tissues containing type I collagen.
Type V collagen is a part of the family of collagen proteins consisting of Collagen I- Collagen XXVIII. Collagen proteins are often associated with the strengthening and support of many tissues including skin, bones, muscles, and ligaments. There are some studies that suggest that Type V collagen is responsible for the formation of other collagen fibrils in different tissues within the body. According to studies, Collagen V regulates the heterotypic fiber diameter. Type V Collagen is considered a regulatory fibril forming collagen. Collagen V is associated with the COL5A1 gene which is the gene which provides instructions to produce Collagen V. Type V Collagen, like other collagens, is made up of procollagen molecules.
Collagen V molecular isoforms are α1(V)α2(V)α3(V), α1(V)3, and α1(V)2 α2(V). These procollagen molecules are made up of three different α -polypeptide chains. These α -polypeptide chains are α1(V), α2(V), and α3(V). Different combinations of these chains form the Type V collagen Isoforms. Procollagen molecules then form mature collagen with the help of enzymes. After the chains are formed, they arrange into thin fibrils. These collagen fibrils then assort with type I collagen fibrils.
Type V collagen is a part of the Extracellular Matrix (ECM). Collagen V is gene expression modulated by TGF-β. Type V collagen has shown that it is resistant to digestion by interstitial collagenases. Denatured collagen V on the other hand, can be degraded by gelatinases as well as metalloproteinases.
Alternative names
Type V collagen has a few alternative names alpha 1 These include: type V collagen preproprotein, CO5A1_HUMAN, and collagen type V alpha. Type V collagen can also be abbreviated to COLV or collagen V.
Diseases associated with type V collagen
Some studies show that a mutation in the gene that codes for Type V collagen is linked as the cause of a form of Ehlers Danlos Syndrome. Ehlers Danlos Syndrome Classical Type is the result of mutations of the COL5A1 or COL5A2 gene which both code for Type V Collagen. This form of the Ehlers Danlos- Syndrome (classical type) is associated with hypermobility, scarring and elasticity of the skin and other tissues. Researchers discovered the cause of this form of Ehlers Danlos is due to the mutation that produces less chains from the three chains that make up Type V Collagen. Over 100 mutations to the gene COL5A1 have been identified. These mutations result in the underproduction of pro-α1(V) chains. With these mutations, Type V Collagen fibrils are not fully developed and disorganized. This results in the different symptoms of Ehlers Danlos Syndrome.
Health
Type V Collagen studies show that Collagen V plays some other roles in different parts of the body. These roles can be both beneficial and harmful.
Beneficial roles that Type V collagen plays in the body are:
Neoepitopes of Type V collagen have shown to be a useful noninvasive serum biomarker for assessing fibrotic progression and resolution in experimental hepatic fibrosis.
Type V Collagens isoform which contains the α3(V) chain is involved in mediating pancreatic islet cell functions.
Type V Collagens will arrange with Type I Collagen and form heterotypic fibrils in the skin dermis and cornea. Together, Collagen V and Collagen I acts as a dominant regulator of collagen fibrillogenesis.
Type V Collagens interacts with matrix collagens and structural proteins. This interaction improves structural integrity to tissue scaffolds.
Harmful roles that Type V collagen can play in the body.
Having a Type V Collagen deficiency has been associated with loss of corneal transparency and classic Ehlers-Danlos syndrome.
Studies have shown that an overexpression of Type V Collagen can lead to harmful responses in the body. Collagen V overexpression has been found in cancer, granulation tissue, inflammation and atherosclerosis. It is also linked to fibrosis of the lungs, skin, kidneys, adipose tissue, and liver.
Increases in Type V Collagen are associated with both early and advanced hepatic fibrosis.
Studies show that increased synthesis of abnormal Type V Collagen is linked to the pathogenesis of Systemic Sclerosis
Autoimmunity against type V collagen is associated with lung transplant failure.
Genes
COL5A1, COL5A2, COL5A3
References
External links
Collagens | Type V collagen | [
"Chemistry"
] | 1,131 | [
"Biochemistry stubs",
"Protein stubs"
] |
12,112,279 | https://en.wikipedia.org/wiki/The%20Critical%20Eye | The Critical Eye is a Discovery Science Channel documentary series examining pseudoscientific and paranormal phenomena. The eight-part documentary series aired from October 2002 through February 2003 and was hosted by actor and scientific skeptic William B. Davis.
Series description
The Critical Eye, alternately labeled as just Critical Eye, was produced by the Discovery Science Channel, and was produced in association with Skeptical Inquirer Magazine. The show was described by cosmolearning.org as "William B. Davis hosts this programme bringing to the viewers the science behind the paranormal and the unexplained."
Historical event references
The series discusses several notable events:
The 1990 civil trial brought against Judas Priest alleging subliminal messaging in their music
The Stargate Project
The Phoenix Lights
The Roswell UFO incident
Project Blue Book
The Heaven's Gate mass suicide
Episodes
Each episode of the series consists of four or five segments focused specifically on one pseudoscientific or paranormal phenomenon. Each segment begins by explaining the phenomenon in question, discusses it with both scientists/skeptics and proponents/believers, and concludes with street interviews regarding the legitimacy of the phenomenon in question.
References
American documentary television series
Documentary television series about science
American English-language television shows
Scientific skepticism mass media
2000s American documentary television series
Pseudoscience
Reiki
Acupuncture
Alternative medicine
Energy (esotericism)
Telepathy
Homeopathy
Parapsychology
Vampirism
Hypnosis
Modern witchcraft
Exorcism
Bigfoot
Loch Ness Monster
Atlantis
Noah's Ark
Extraterrestrial life
Near-death experiences
Ghosts
Reincarnation
Mediumship
Nostradamus
Stonehenge
Pyramids | The Critical Eye | [
"Astronomy",
"Biology"
] | 329 | [
"Biological hypotheses",
"Extraterrestrial life",
"Astronomical controversies",
"Hypothetical life forms"
] |
12,112,654 | https://en.wikipedia.org/wiki/Pull%20technology | Pull coding or client pull is a style of network communication, where the initial request for data originates from the client, and then is responded to by the server. The reverse is known as push technology, where the server pushes data to clients.
Pull requests form the foundation of network computing, where many clients request data from centralized servers. Pull is used extensively on the Internet for HTTP page requests from websites.
A push can also be simulated using multiple pulls within a short amount of time. For example, when pulling POP3 email messages from a server, a client can make regular pull requests, every few minutes. To the user, the email then appears to be pushed, as emails appear to arrive close to real-time. A trade-off of this system is that it places a heavier load on both the server and network to function correctly.
Many web feeds, such as RSS are technically pulled by the client. With RSS, the user's RSS reader polls the server periodically for new content; the server does not send information to the client unrequested. This continual polling is inefficient and has contributed to the shutdown or reduction of several popular RSS feeds that could not handle the bandwidth. For solving this problem, the WebSub protocol, as another example of a push code, was devised.
Podcasting is specifically a pull technology. When a new podcast episode is published to an RSS feed, it sits on the server until it is requested by a feed reader, mobile podcasting app, or directory. Directories such as Apple Podcasts (iTunes), The Blubrry Directory, and many apps' directories request the RSS feed periodically to update the Podcast's listing on those platforms. Subscribers to those RSS feeds via app or reader will get the episodes when they request the RSS feed next time, independent of when the directory listing updates.
See also
Push technology
Client–server model
References
Internet terminology
Web development | Pull technology | [
"Technology",
"Engineering"
] | 399 | [
"Computing terminology",
"World Wide Web stubs",
"Internet terminology",
"Web development",
"Software engineering",
"Computing stubs"
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12,112,898 | https://en.wikipedia.org/wiki/Richard%20Muther%20%28industrial%20engineer%29 | Richard Muther (November 20, 1913 – October 15, 2014) was an American consulting engineer, faculty member at MIT, and author. He developed fundamental techniques used in plant layout, material handling, and other aspects of industrial engineering. He was also known as "Mister Systematic".
Biography
Muther was born 1913 in Newton, Massachusetts to Lorenz Francis Muther and Josephine (Ashleman) Muther. After attending the University of Wisconsin, he obtained his B.S. and M.S. from the Massachusetts Institute of Technology.
In his early career Muther worked for the Methods Engineering Council in Pittsburgh, the consulting firm of Harold Bright Maynard. In 1956 he founded his own consulting firm, Richard Muther and Associates, and worked as consulting engineer for organizations, such as Vendo in Kansas City, General Dynamics, Philips in the Netherlands, John Deere, and in the People's Republic of China for its Department of Energy.
In World War II Muther served in the US Navy as expediter and facilities planning officer. In 1944 he published his first book, entitled Production Line Technique, on mass production methods, based on studies at over 75 industrial plants.
Over the years Muther had taught at Massachusetts Institute of Technology, at the Naval Postgraduate School, and at Robert College in Turkey. He was visiting professor and instructor at the University of Missouri–Kansas City, and in Europe at the ETH Zurich in Switzerland, and at the Royal Institute of Technology in Sweden.
Muther received an honorary doctorate ScD(hc) from Lund University in Sweden. He also was awarded the Gilbreth Medal (outstanding contributions to Industrial Engineering) in 1962; the Materials Handling Award (SAM); the Engineering Citation Award (SME); the Honor Award (IMMS); the Reed-Apple Award (MHIA); and the Donald Francis Award (for outstanding contributions to international material handling.)
Contributions to engineering
Muther was the original developer of relationship chart (REL-CHART) and its companion space-relationship diagram. This tool is the basis for many other techniques which are used to optimize the proximity of related functions and minimize unnecessary transportation in industrial facilities.
Muther also created the Mag Count method of measuring the difficulty of handling (transporting) any solid material prior to knowing how it will be moved. He developed the industry-standard color code used to classify industrial space and the related type-of-work symbols. Corresponding black-and-white hatch patterns based on the heraldic tincture code are also part of his methodology. He is considered the "Father of Systematic Planning".
Selected publications
Production Line Technique. New York: McGraw-Hill, 1944.
Practical Plant Layout. New York: McGraw-Hill, 1955.
Systematic Layout Planning (SLP). 1st edition. 1961; 2nd edition. Boston: Cahners Books, 1974, ; Re-printed by Management & Industrial Research Publications, 1987, .
Systematic Handling Analysis (SHA) (Kansas City, Missouri: Management and Industrial research Publications, 1969).
Systematic Planning of Industrial Facilities (SPIF), 1979; 1980; 1999.
Planning By Design,'' 2010
References
External links
Richard Muther & Associates
RICHARD MUTHER '38, SM '41: Early Break Sparks Career in Production Management
1913 births
2014 deaths
Industrial engineering
American industrial engineers
University of Wisconsin–Madison alumni
Massachusetts Institute of Technology alumni
MIT School of Engineering faculty
People from Newton, Massachusetts
American men centenarians | Richard Muther (industrial engineer) | [
"Engineering"
] | 698 | [
"Industrial engineering"
] |
12,114,439 | https://en.wikipedia.org/wiki/Quick%20time%20event | In video games, a quick time event (QTE) is a method of context-sensitive gameplay in which the player performs actions on the control device shortly after the appearance of an on-screen instruction/prompt. It allows for limited control of the game character during cut scenes or cinematic sequences in the game. Performing the wrong prompt, mistiming the action, or not performing any action at all results in the character's failure at their task, resulting in a death/failure animation and often an immediate game over or the loss of a life, with some games providing a lesser but significant penalty of sorts instead.
The term "quick time event" is attributed to Yu Suzuki, director of the game Shenmue which used the QTE feature (then called "quick timer events") to a great degree. They allow for the game designer to create sequences of actions that cannot be expressed through the game's standard control scheme, or to constrain the player into taking only one specific action at a critical moment.
While some uses of QTE have been considered as favorable additions to gameplay, the general use of QTE has been panned by journalists and players alike, as these events can break the flow of the game and force the player to repeat sections until they master the event, adding false difficulty to the game.
Mechanics
QTEs generally involve the player following onscreen prompts to press buttons or manipulate joysticks within a limited amount of time. Games played on systems controlled with motion controllers, such as Nintendo's seventh-generation Wii and Nintendo DS, may also implement QTEs with appropriate gestures (for example, the Wii version of Tomb Raider Anniversary requires players to thrust both the Wii Remote and Nunchuk, held in each hand, forward simultaneously to evade a dangerous situation in a cutscene). The prompts are often displayed as a graphical image of the physical controller button; for example, games on PlayStation systems may show any of the four shape-marked face buttons (cross, square, circle or triangle) on the DualShock controller as input for the event. Such actions are either atypical of the normal controls during the game or in a different context from their assigned functions. Whilst most prompts simply require the player to push the appropriate button in time, some may require different types of actions, such as repeatedly pressing a button a certain number of times within the time limit or hitting the button with precise timing.
History
Although the origin of QTE are often attributed to interactive movie laserdisc video games that showed video clips stored on a laserdisc like Dragon's Lair (Cinematronics, June 1983), Cliff Hanger (Stern, December 1983) and Road Blaster (Data East, 1985), these left little room for more advanced gameplay elements. These games had graphics on par with animated cartoons at a time when video games were composed of simple, pixelated characters. Their gameplay consisted of watching an animated video and pressing the correct button every few seconds to avoid seeing a (circumstance-specific) loss scene and losing a life. Compared to modern titles, games like Dragon's Lair would require the player to memorize the proper sequence and timing of their input, effectively making the entire game one continuous QTE. Such uses were also seen as giving the player only the illusion of control, as outside of responding to QTE, there were no other commands the player could enter; effectively, these games were considered the equivalent of watching a movie and responding every few minutes to allow it to continue. An improvement to the QTE mechanic was flashing the buttons that need to be pressed on the screen, which appeared in the laserdisc games Super Don Quix-ote (Universal, 1984), Ninja Hayate (Taito, 1984), Time Gal (Taito, 1985) and Road Blaster.
Die Hard Arcade (Sega, 1996), Sword of the Berserk: Guts' Rage and most notably Shenmue (Sega, 1999) for the Dreamcast introduced QTEs in the modern form of cutscene interludes in an otherwise more interactive game. Shenmues director Yu Suzuki is credited with coining the phrase "Quick Time Event", which were included in the game as to provide "a fusion of gameplay and movie" and create cinematic experience to the player. The game's manual called them "quick timer events", but the phrase became popularized as "quick time events" since its release. Since this period, several other games on modern console and game systems have included QTEs or similar mechanics, and are not limited to the action or adventure genre. For instance, in the Wii version of the sports games 2010 FIFA World Cup South Africa, QTEs are used to save penalty shots and free kicks aimed towards the goal, or win possession of the ball after it is punted or corner-kicked. Failure to execute the quick time event in time would result in the opposing team scoring a goal or claiming possession of the ball.
To improve game accessibility, action games increasingly contain options to individually disable quick time events and other design elements that contribute to a game's difficulty.
Use and critical reaction
QTEs have received mixed reactions from players and journalists. They can be used effectively to enhance cutscenes and other actions. The use of QTEs within Shenmue is often praised, as "they seamlessly flow from cinema to the QTE sequence without any loading pauses at all", and sections which utilized the QTE were considered "some of the most thrilling in the whole game". At the same time, they also are considered to be a weak addition to gameplay, and often force the player to repeat such sections until they complete the QTE perfectly to move on. They are often considered a "bane of action games", as their presence breaks the standard flow of the game and reduce the control of the game for the player to a few buttons, distracting, and turning interactivity into a job. Also, QTEs may frustrate the player due to the fact that they might not have any sign that they are about to happen.
QTEs are often used during dramatic cutscenes. Resident Evil 4 uses QTEs (described by cinematics lead Yoshiaki Hirabayashi as an "action button system") to "facilitate a seamless transition between gameplay and the in-game movies" and prevent players from losing interest during cutscenes. One example in Resident Evil 4 is a knife fight. The fight occurs during a late-game cutscene where the protagonist meets a major villain, who explains missing links in the game's story while periodically slashing at the protagonist and requiring the player to quickly press a button to parry him. As the action takes place during the major revelation of the game, the QTE serves to prevent the player from skipping over the cutscene. While this example is considered to use QTEs effectively, punctuating the heated discussion between the characters with rapid player reactions, it also demonstrates a common failing with the mechanism, in that if the player should miss a QTE, the protagonist will be killed, and the player must restart the cutscene and the fight from the start. Because of the likelihood of player death, the phrase "Press X to not die" has become synonymous with the use of QTEs in game. Furthermore, when a QTE is used during such a scene, the player's attention is drawn away from the animation and instead to the area of the screen where the button control indicator would appear, rendering the effort put into animating the scene meaningless.
Another problem with the use of QTE during cutscenes is that it can dilute the emotion and importance of the scene to a single button press, trivializing the nature of the scene. This issue was raised from Call of Duty: Advanced Warfare, in which during an early scene where the player character attends the funeral of a fallen fellow soldier, the player is given the option to press a button to mourn for the soldier. Forcing this type of interaction has been considered a poor form of storytelling, as some have argued the scene could have been played out without requiring player action to make the same form of emotional connection to the protagonist, or with the player given more control of the character.
QTEs may be used to provide a limited control scheme for a scene within the game that would be otherwise difficult or impossible to perform with the game's standard controls. A second example from Shenmue II requires the player to navigate several narrow planks across a void in a disused building, every so often responding to a QTE to regain the character's balance, with each successive plank requiring more and quicker responses to QTEs. Failing to respond to the QTE leads to the character's death and requiring the player to restart the sequence. This sequence has been strongly criticized, as when the plank sequence is finished, the player is rejoined by another character who had used the elevator to bypass the floors, an option not given to the player.
More recent games have used QTEs that occur more directly in gameplay and, when failed, do not end the game for the player. The God of War series uses QTEs as finishing moves: by completing the maneuver successfully, the player can defeat larger beasts or bosses, but failure to complete only leads to being tossed away, upon which the player can move back into battle to continue to fight. Often these are progressive QTE systems where the player is only partially penalized for missing the necessary commands; these often take place in boss battles. An example of this usage is from the game Ninja Blade; during a special attack by the boss, the player can attempt a series of QTEs to minimize the distance that the protagonist is pushed back down a long hallway from the boss, reducing the amount of time and damage that the character would then take in rushing the boss at the conclusion of the attack. Other positive means of incorporating the QTE is for manipulating the environment to gain a tactical edge; Gears of War 2, for example, includes one area where the player character and his non-player character squad are on a circular elevator, fending off hordes of monsters engaging them on all sides. By temporarily abandoning the battle, the player can engage the elevator through a QTE at its control panel to gain the high ground, though this gain can be nullified if the monsters engage a second control panel.
More recent use of QTEs have been within cutscenes themselves where failing to perform the QTE may alter or provide more details about the game's story and affect the character later in the game, though the changes are generally minimal, essentially boiling down to a "what if?" scenario. In Mass Effect 2 and Mass Effect 3, certain cutscenes contain dramatic moments where a QTE will appear for a short moment, indicating an action that will drive the character towards either extreme of a morality scale. In one case, the player is given the opportunity to stop ruffians from firing upon a weaker character, with the QTE provided helping to boost the player towards higher moral standing. Telltale Games' The Walking Dead includes QTEs intermittently, creating tension throughout the game. Furthermore, during conversation trees with non-player characters, failure to select the next choice of topic in a limited time may affect later events in the game. This "quick time conversation" mechanic is used in other Telltale games as well.
More recently, the games Fahrenheit (Indigo Prophecy in North America), Heavy Rain, and Detroit: Become Human from Quantic Dream are primarily presented as sequences of QTEs, integrating the mechanic as part of the core gameplay, and present controller actions that correlate directly with the character actions on the screen; this was emphasized further in Heavy Rain by a game patch to support the use of the PlayStation Move motion controls where the player could actually physically perform the moves that corresponded with character actions. In both games, players may miss certain QTEs, or may be given a choice of multiple QTEs they could perform; opting of which QTEs to perform would alter the story, with the possibility of character death at some later point. In Heavy Rain, for example, the player controls the fates of the game's four playable characters, leading to numerous different endings if the characters remained alive and if they had discovered critical information. Even prior to Heavy Rains release, the game's director David Cage had to defend his vision of the game from critics that were skeptical of the reliance on QTEs within Heavy Rain and created an early stigma on the game's reception. Despite the integration, Heavy Rain was often criticized for use of QTEs in otherwise non-dramatic situations. In an early sequence in the game, the player has to control the lead character to find his son Jason in the mall, with the only available action of pressing the "X" button to shout "Jason" having no apparent effect.
With the onset of newer technology to improve graphics, controls, in-game physics, and artificial intelligence, gameplay elements previously simulated through QTEs can potentially be re-implemented as core game mechanics. Road Blaster used QTEs to steer the car and ram other vehicles off the road in pre-rendered animated scenes, while a modern game like Burnout Paradise gives the player full control of the vehicle and uses its game engine to create real-time crashes with other vehicles. Similarly, Dragon's Lair 3D: Return to the Lair recreates the experience of the pre-animated scenes from Dragon's Lair as a platform game, allowing the player to react freely to the environmental traps and monsters.
References
Video game terminology | Quick time event | [
"Technology"
] | 2,762 | [
"Computing terminology",
"Video game terminology"
] |
12,114,535 | https://en.wikipedia.org/wiki/DiI | DiI, pronounced like Dye Aye, also known as DiIC18(3), is a fluorescent lipophilic cationic indocarbocyanine dye and indolium compound, which is usually made as a perchlorate salt. It is used for scientific staining purposes such as single molecule imaging, fate mapping, electrode marking and neuronal tracing (as DiI is retained in the lipid bilayers).
DiI is manufactured by Invitrogen, which has a series of long-chain lipophilic carbocyanine dyes, of which DiI is one of the most well researched members. Some prominent members of the series includes: DiI, also called DiIC18(3); DiO, also called DiOC18(3); DiD, also called DiIC18(5); and DiR, also called DiIC18(7), which exhibit distinct orange, green, red and infrared fluorescence, respectively, and all have the following useful properties, according to the manufacturer:
Diffuse laterally to stain the entire cell
Fluoresce weakly in water but highly fluorescent and quite photostable when incorporated into membranes
Possess very bright signals with high extinction coefficients
Are well retained in cell membranes
Demonstrate very little transfer to other cells
Name and chemical structure
The "Di" possibly stands for the di-alkyl nature and the "I" of DiI possibly stands for the "indocarbocyanine" group (which it shares with D383, D384, D3886, D3899, D3911, D7756, D7776, D7777, D12730, N22880). The full chemical name of this major member of the group is 1,1'-dioctadecyl-3,3,3'3'-tetramethylindocarbocyanine perchlorate, the chemical formula is C59H97ClN2O4
It has 18-carbon-long straight alkyl hydrocarbon tails on each on the nitrogen (Position 1) of the two indoline rings, a conjugated 3-carbon bridge connecting the 2nd positions (Carbon) on the rings symmetrically, and two methyl groups each on each of the 3rd positions (carbon) of the two rings. The longer names e.g. DiIC18(3) mention the length of the alkyl chain (e.g. 18) and the length of the conjugated bridge between the aromatic rings e.g. 3.
Derivatives and analogs
DiI has several derivatives and analogs in use:
CM-DiI (C-7000, C-7001) is a fixable analogue of DiI. It has a thiol-reactive chloromethyl (CM) group that makes it more soluble in aqueous solution i.e. culture media and aldehyde-fixable. It has together with SP-DiIC18(3) been demonstrated to be compatible with the tissue clearing method CLARITY, that relies on an extensive lipid removal by detergent (SDS).
FAST DiI (D-3899 oil, D-7756 solid crystals) has diunsaturated linoleyl (C18:2; Δ9,12) tails in place of the saturated octadecyl tails (C18:0). It reportedly migrates ~50% faster than DiI within membranes.
Monounsaturated DiI analog (D-3886, oil) with oleate (C18:1, Δ9) tails is also available. It might also migrate faster than DiI within the membrane.
5,5′-Ph2-DiIC18(3) (D-7779) has phenyl substituents attached to the indoline rings of DiI, making it more lipophilic and significantly more fluorescent. It has higher quantum yield and longer-wavelength spectra (red-shifted by ~20 nm).
Anionic DiI analogs with potentially enhanced solubility in culture media:
Sulfonate analogs e.g.: D-7776 or DiIC18(3)-DS
Sulfophenyl (SP) analogs e.g.: D-7777 or SP-DiIC18(3)
Shorter chain DiI analogs:
D-383 or DiIC12(3)
D-384 or DiIC16(3)
DiI and DiO analogs with tails much shorter than 12C, usually less than 7C are used as membrane-potential sensors for mitochondria, based on their vertical sinking into or floating up with respect to a lipid bilayer driven by electric field which changes their fluorescence due to the change in the ambient hydrophobic and charge environment around the fluorescent aromatic rings (they are sensors based on physical movement of whole molecule thus slower compared to membrane potential sensors that work by electron redistribution). Analogs with both intermediate and short tails may be used as organelle stains e.g. of the endoplasmic reticulum.
Longer wavelength excitable analogs (longer bridges)
"DiD" or DiIC18(5) (D-307,D-7757) has a 5 carbon bridge, and long-wavelength visible light–excitable analog with red emission
"DiR" or DiIC18(7) (D-12731) has a 7 carbon bridge, with excitation and emission both in the infrared range thus may not be visible without a CCD or other sensing device that can capture optical signal of infrared nature. But they cause comparative less photodamage to tissue. Thus they can be conveniently used for in vivo imaging.
Physical properties
The dye (DiIC18(3)) is a violet crystal that is soluble in ethanol, methanol, dimethylformamide, and dimethylsulfoxide.
The crystal form of the dye has melting point of 68 °C (at which it decomposes).
The dye had an absorption maximum at 549 nm and an emission maximum 565 nm similar to tetramethyl rhodamine. It is mildly fluorescent in aqueous suspension, but becomes bright when bound to cell membrane. Once bound to a membrane, it diffuses laterally in 2 dimensions; if there is no diffusion barrier, DiI generally stains the whole leaflet (one surface) of a biological membrane rapidly, but does not readily flip across to the other leaflet.
See also
DiOC6
References
Staining dyes
Cyanine dyes
Perchlorates | DiI | [
"Chemistry"
] | 1,376 | [
"Perchlorates",
"Salts"
] |
12,114,623 | https://en.wikipedia.org/wiki/Petrol%20interceptor | A petrol interceptor is a trap used to filter out hydrocarbon pollutants from rainwater runoff. It is typically used in road construction and on Petrol Station forecourts to prevent fuel contamination of streams carrying away the runoff.
Petrol interceptors work on the premise that some hydrocarbons such as petroleum and diesel float on the top of water. The contaminated water enters the interceptor typically after flowing off roads or forecourts and entering a channel drain before being deposited into the first tank inside the interceptor. The first tank builds up a layer of the hydrocarbon as well as other scum. Typically petrol interceptors have 3 separate tanks each connected with a dip pipe. As more liquid enters the interceptor the water enters into the second tank leaving the majority of the hydrocarbon behind as it cannot enter the dip pipe, whose opening into the second tank is below the surface of the water. However some of the contaminants may by chance enter the second tank. This second tank will not build up as much of the hydrocarbon on its surface. As before, the water is pushed into the third tank, by fluid dynamics, as more water enters the second. The third tank should be practically clear of any hydrocarbon floating on its surface. As a precaution, the outlet pipe is also a dip pipe. When the water leaves the third tank via the outlet pipe it should be contaminant free.
References
Water filters | Petrol interceptor | [
"Chemistry",
"Engineering"
] | 288 | [
"Water filters",
"Water treatment",
"Filters",
"Civil engineering",
"Civil engineering stubs"
] |
12,114,730 | https://en.wikipedia.org/wiki/List%20of%20bird%20genera | List of bird genera concerns the chordata class of aves or birds, characterised by feathers, a beak with no teeth, the laying of hard-shelled eggs, and a high metabolic rate.
Accipitriformes
Eagles, Old World vultures, secretary-birds, hawks, harriers, etc.
Family Accipitridae - buzzards, eagles, harriers, hawks, kites, Old World vultures
Genus Accipiter
Genus Aegypius
Genus Aquila
Genus Aviceda
Genus Busarellus
Genus Butastur
Genus Buteo (probably paraphyletic, might include Leucopternis in part and Parabuteo)
Genus Buteogallus (probably paraphyletic, might include Leucopternis in part)
Genus Chelictinia
Genus Chondrohierax
Genus Circaetus
Genus Circus
Genus Clanga
Genus Cryptoleucopteryx – plumbeous hawk
Genus Elanoides - swallow-tailed kite
Genus Elanus
Genus Erythrotriorchis
Genus Eutriorchis - Madagascan serpent eagle
Genus Gampsonyx - pearl kite
Genus Geranoaetus
Genus Geranospiza - crane hawk
Genus Gypaetus - bearded vulture
Genus Gypohierax - palm-nut vulture
Genus Gyps
Genus Haliaeetus - sea eagles
Genus Haliastur
Genus Hamirostra - black-breasted buzzard
Genus Harpagus
Genus Harpia - harpy eagle
Genus Harpyhaliaetus
Genus Harpyopsis - Papuan eagle
Genus Helicolestes – slender-billed kite, formerly included in Rostrhamus
Genus Henicopernis
Genus Hieraaetus
Genus Icthyophaga
Genus Ictinaetus - black eagle
Genus Ictinia
Genus Kaupifalco - lizard buzzard
Genus Leptodon
Genus Leucopternis (probably polyphyletic)
Genus Lophaetus - long-crested eagle (possibly junior synonym of Ictinaetus)
Genus Lophoictinia - square-tailed kite
Genus Lophotriorchis - rufous-bellied eagle
Genus Macheiramphus - bat hawk (was doubtfully placed, moved from Perninae)
Genus Megatriorchis - Doria's goshawk
Genus Melierax
Genus Micronisus - Gabar goshawk
Genus Milvus
Genus Morphnarchus – barred hawk
Genus Morphnus - crested eagle
Genus Necrosyrtes - hooded vulture
Genus Neophron - Egyptian vulture
Genus Nisaetus
Genus Parabuteo
Genus Pernis
Genus Pithecophaga
Genus Polemaetus
Genus Polyboroides
Genus Pseudastur
Genus Rostrhamus - snail kite
Genus Rupornis – roadside hawk
Genus Sarcogyps - red-headed vulture
Genus Spilornis
Genus Spizaetus
Genus Stephanoaetus
Genus Terathopius - bateleur
Genus Torgos - lappet-faced vulture
Genus Trigonoceps - white-headed vulture
Genus Urotriorchis - long-tailed hawk
Family Cathartidae - New World vultures
Genus Cathartes
Genus Coragyps - black vulture
Genus Gymnogyps
Genus Sarcoramphus - king vulture
Genus Vultur - Andean condor
Family Pandionidae - osprey
Genus Pandion
Family Sagittariidae - secretarybird
Genus Sagittarius
Anseriformes
Waterfowl
Family Anhimidae - screamers
Genus Anhima - horned screamer
Genus Chauna
Family Anatidae
Genus Aix - Mandarin duck and wood duck – dabbling ducks or Tadorninae?
Genus Alopochen - Egyptian goose and Mascarene shelducks
Genus Amazonetta - Brazilian teal
Genus Anas - pintails, mallards, etc.
Genus Anser - grey geese and white geese
Genus Aythya - pochards, scaups, etc.
Genus Biziura - musk ducks
Genus Branta - black geese
Genus Bucephala - goldeneyes
Genus Cairina - Muscovy duck and white-winged duck (traditionally dabbling ducks, but may be paraphyletic)
Genus Callonetta - ringed teal (dabbling ducks or Tadorninae?)
Genus Cereopsis - Cape Barren goose (Anserinae, Tadorninae, or own subfamily?)
Genus Chenonetta - maned duck (dabbling ducks or Tadorninae? Includes Euryanas.)
Genus Chloephaga - sheldgoose
Genus Clangula - long-tailed duck
Genus Coscoroba - coscoroba swan (Anserinae or same subfamily as Cereopsis?)
Genus Cyanochen - blue-winged goose (Tadorninae or more distant clade?)
Genus Cygnus - true swans
Genus Dendrocygna - whistling ducks
Genus Heteronetta - black-headed duck
Genus Histrionicus - harlequin duck (includes Ocyplonessa)
Genus Hymenolaimus - blue duck
Genus Lophodytes - hooded merganser
Genus Lophonetta - crested duck
Genus Malacorhynchus - pink-eared ducks (Tadorninae, Oxyurinae or Dendrocheninae?)
Genus Mareca - wigeons and gadwalls
Genus Marmaronetta - marbled duck
Genus Melanitta - scoters
Genus Merganetta - torrent duck
Genus Mergellus - smew
Genus Mergus - mergansers
Genus Neochen
Genus Netta - red-crested pochard and allies
Genus Nettapus - pygmy geese
Genus Nomonyx - masked duck
Genus Oxyura - stiff-tailed ducks
Genus Plectropterus - spur-winged goose
Genus Polysticta - Steller's eider
Genus Pteronetta - Hartlaub's duck
Genus Radjah - Radjah shelduck
Genus Salvadorina - Salvadori's teal
Genus Sarkidiornis - comb duck (Tadorninae or closer to dabbling ducks?)
Genus Sibirionetta - Baikal teal
Genus Somateria - eiders
Genus Spatula - shovelers
Genus Speculanas - bronze-winged duck
Genus Stictonetta - freckled duck
Genus Tachyeres - steamer ducks (Tadorninae or closer to dabbling ducks?)
Genus Tadorna - shelducks (possibly paraphyletic)
Genus Thalassornis - white-backed duck
Family Anseranatidae
Genus Anseranas
Apodiformes
Swifts, treeswifts and hummingbirds
Family Apodidae - swifts
Genus Aerodramus sometimes included in Collocalia
Genus Aeronautes
Genus Apus
Genus Chaetura
Genus Collocalia
Genus Cypseloides
Genus Cypsiurus
Genus Hirundapus
Genus Hydrochous - giant swiftlet
Genus Mearnsia
Genus Neafrapus
Genus Panyptila
Genus Rhaphidura
Genus Schoutedenapus - African swiftlets
Genus Streptoprocne
Genus Tachornis
Genus Tachymarptis
Genus Telacanthura
Genus Zoonavena
Family Hemiprocnidae - treeswifts
Genus Hemiprocne
Family Trochilidae - hummingbirds
Genus Abeillia – emerald-chinned hummingbird
Genus Adelomyia – speckled hummingbird
Genus Aglaeactis – sunbeams
Genus Aglaiocercus – sylphs
Genus Amazilia (includes Agyrtria)
Genus Androdon – tooth-billed hummingbird
Genus Anopetia – broad-tipped hermit
Genus Anthocephala – blossomcrowns
Genus Anthracothorax – mangos
Genus Aphantochroa – sombre hummingbird
Genus Archilochus
Genus Atthis
Genus Augastes – visorbearers
Genus Avocettula – fiery-tailed awlbill
Genus Basilinna (recently split from Hylocharis)
Genus Boissonneaua – coronets
Genus Calliphlox – Calliphlox woodstars
Genus Calothorax – Calothorax sheartails
Genus Calypte
Genus Campylopterus – sabrewings
Genus Chaetocercus – Chaetocercus woodstars
Genus Chalcostigma – Chalcostigma thornbills
Genus Chalybura – plumeleteers
Genus Chlorestes – blue-chinned sapphire
Genus Chlorostilbon – typical emeralds
Genus Chrysolampis – ruby-topaz hummingbird
Genus Chrysuronia – golden-tailed sapphire
Genus Clytolaema – Brazilian ruby
Genus Coeligena – Incas and starfrontlets
Genus Colibri – violet-ears
Genus Cyanophaia - blue-headed hummingbird
Genus Cynanthus
Genus Damophila – violet-bellied hummingbird
Genus Discosura – thorntails
Genus Doricha – typical sheartails
Genus Doryfera – lancebills
Genus Elvira – elvira emeralds
Genus Ensifera – sword-billed hummingbird
Genus Eriocnemis – typical pufflegs
Genus Eugenes
Genus Eulampis – caribs
Genus Eulidia – Chilean woodstar
Genus Eupetomena – swallow-tailed hummingbird
Genus Eupherusa
Genus Eutoxeres – sicklebills
Genus Florisuga – jacobins
Genus Glaucis
Genus Goethalsia – pirre hummingbird
Genus Goldmania – violet-capped hummingbird
Genus Haplophaedia – Haplophaedia pufflegs
Genus Heliactin – horned sungem
Genus Heliangelus – sunangels
Genus Heliodoxa – brilliants
Genus Heliomaster – starthroats
Genus Heliothryx – fairies
Genus Hylocharis – typical sapphires
Genus Hylonympha – scissor-tailed hummingbird
Genus Klais – violet-headed hummingbird
Genus Lafresnaya – mountain velvetbreast
Genus Lampornis – typical mountaingems
Genus Lamprolaima – garnet-throated hummingbird
Genus Lepidopyga
Genus Lesbia – trainbearers
Genus Leucippus
Genus Leucochloris – white-throated hummingbird
Genus Loddigesia – marvelous spatuletail
Genus Lophornis – coquettes
Genus Mellisuga
Genus Metallura – metaltails
Genus Microchera – snowcap
Genus Microstilbon – slender-tailed woodstar
Genus Myrmia – short-tailed woodstar
Genus Myrtis – purple-collared woodstar
Genus Ocreatus – booted racket-tails
Genus Opisthoprora – mountain avocetbill
Genus Oreonympha – bearded mountaineer
Genus Oreotrochilus – hillstars
Genus Orthorhyncus – Antillean crested hummingbird
Genus Oxypogon – bearded helmetcrests
Genus Panterpe – fiery-throated hummingbird
Genus Patagona – giant hummingbird
Genus Phaeochroa – scaly-breasted hummingbird
Genus Phaethornis – typical hermits
Genus Phlogophilus – piedtails
Genus Polyonymus – bronze-tailed comet
Genus Polytmus – goldenthroats
Genus Pterophanes – great sapphirewing
Genus Ramphodon – saw-billed hermit
Genus Ramphomicron – typical thornbills
Genus Rhodopis – oasis hummingbird
Genus Sappho – red-tailed comet
Genus Schistes - wedgebills (sometimes included in Augastes)
Genus Selasphorus
Genus Sephanoides – firecrowns
Genus Stephanoxis – plovercrests
Genus Sternoclyta – violet-chested hummingbird
Genus Taphrolesbia – grey-bellied comet
Genus Taphrospilus - many-spotted hummingbird
Genus Thalurania – woodnymphs
Genus Thaumastura – Peruvian sheartail
Genus Threnetes – barbthroats
Genus Tilmatura – sparkling-tailed woodstar
Genus Topaza – topazes
Genus Trochilus – streamertails
Genus Urochroa – white-tailed hillstar
Genus Urosticte – whitetips
Apterygiformes
Family Apterygidae
Genus Apteryx - kiwi
Bucerotiformes
Hornbills, hoopoes, and wood-hoopoes
Family Bucerotidae
Genus Aceros - rufous-necked hornbill
Genus Anorrhinus - brown hornbill
Genus Anthracoceros - pied hornbill
Genus Berenicornis - white-crowned hornbill (sometimes included in Aceros)
Genus Buceros
Genus Bycanistes
Genus Ceratogymna - casqued hornbill
Genus Lophoceros
Genus Ocyceros - grey hornbill
Genus Penelopides
Genus Rhinoplax - helmeted hornbill (sometimes included in Buceros)
Genus Rhyticeros (sometimes included in Aceros)
Genus Tockus
Genus Tropicranus - white-crested hornbill (sometimes included in Tockus)
Family Bucorvidae
Genus Bucorvus - ground hornbills
Family Phoeniculidae
Genus Phoeniculus - wood hoopoes
Genus Rhinopomastus - scimitarbills
Family Upupidae
Genus Upupa - hoopoes
Caprimulgiformes
Nightjars, nighthawks, potoos, oilbirds, frogmouths and owlet-nightjars
Family Aegothelidae - owlet-nightjars
Genus Aegotheles
Family Caprimulgidae - nightjars
Genus Antrostomus
Genus Caprimulgus
Genus Chordeiles
Genus Eleothreptus
Genus Eurostopodus
Genus Gactornis – collared nightjar
Genus Hydropsalis
Genus Lurocalis
Genus Lyncornis
Genus Macropsalis – long-trained nightjar
Genus Nyctidromus
Genus Nyctiphrynus
Genus Nyctipolus
Genus Nyctiprogne
Genus Phalaenoptilus – common poorwill
Genus Setopagis
Genus Siphonorhis
Genus Systellura
Genus Uropsalis
Family Nyctibiidae - potoos
Genus Nyctibius
Family Podargidae - frogmouths
Genus Batrachostomus
Genus Podargus
Genus Rigidipenna - Solomons frogmouth
Family Steatornithidae - oilbird
Genus Steatornis
Cariamiformes
Family Cariamidae - seriemas
Genus Cariama
Genus Chunga
Casuariiformes
Cassowaries and emus
Family Casuariidae
Genus Casuarius - cassowary
Genus Dromaius - emu
Cathartiformes
New World vultures
Family Cathartidae
Genus Cathartes
Genus Coragyps - black vulture
Genus Gymnogyps
Genus Sarcoramphus - king vulture
Genus Vultur - Andean condor
Charadriiformes
Plovers, crab plovers, lapwings, seagulls, puffins, auks, sandpipers, buttonquails, stilts, avocets, ibisbills, woodcocks, skuas, etc.
Family Alcidae - puffins, guillemots, murres, and allies
Genus Aethia - auklets
Genus Alca - razorbill
Genus Alle - little auk
Genus Brachyramphus - murrelets
Genus Cepphus - guillemots
Genus Cerorhinca - rhinoceros auklet
Genus Fratercula - puffins
Genus Ptychoramphus - Cassin's auklet
Genus Synthliboramphus - murrelets
Genus Uria - murres
Family Burhinidae - thick-knees
Genus Burhinus
Genus Esacus
Family Charadriidae - plovers and lapwings
Genus Anarhynchus - wrybill
Genus Charadrius
Genus Elseyornis - black-fronted dotterel
Genus Erythrogonys - red-kneed dotterel
Genus Oreopholus - tawny-throated dotterel
Genus Peltohyas - inland dotterel
Genus Phegornis - diademed sandpiper-plover
Genus Pluvialis
Genus Thinornis
Genus Vanellus
Family Chionididae - sheathbills
Genus Chionis
Family Dromadidae - crab plover
Genus Dromas
Family Glareolidae - pratincoles and coursers
Genus Cursorius
Genus Glareola
Genus Rhinoptilus
Genus Stiltia - Australian pratincole
Family Haematopodidae - oystercatchers
Genus Haematopus
Family Ibidorhynchidae - ibisbill
Genus Ibidorhyncha
Family Jacanidae - jacanas
Genus Actophilornis
Genus Hydrophasianus - pheasant-tailed jacana
Genus Irediparra - comb-crested jacana
Genus Jacana
Genus Metopidius - bronze-winged jacana
Genus Microparra - lesser jacana
Family Laridae - gulls, terns, and skimmers
Genus Anous
Genus Chlidonias - marsh tern
Genus Chroicocephalus
Genus Creagrus - swallow-tailed gull
Genus Gelochelidon - gull-billed tern
Genus Gygis - white tern
Genus Hydrocoloeus - little gull
Genus Hydroprogne - Caspian tern
Genus Ichthyaetus
Genus Larosterna - Inca tern
Genus Larus
Genus Leucophaeus
Genus Onychoprion
Genus Pagophila - ivory gull
Genus Phaetusa - large-billed tern
Genus Rhodostethia - Ross's gull
Genus Rissa - kittiwakes
Genus Rynchops - skimmers
Genus Sterna
Genus Sternula
Genus Thalasseus
Genus Xema - Sabine's gull
Family Pedionomidae - plains wanderer
Genus Pedionomus
Family Pluvianellidae - Magellanic plover
Genus Pluvianellus
Family Pluvianidae - Egyptian plover
Genus Pluvianus
Family Recurvirostridae - avocets and stilts
Genus Cladorhynchus - banded stilt
Genus Himantopus - stilts
Genus Recurvirostra - avocets
Family Rostratulidae - painted snipes
Genus Nycticryphes
Genus Rostratula
Family Scolopacidae - snipe, sandpipers, phalaropes, and allies
Genus Actitis
Genus Arenaria - turnstones
Genus Bartramia - upland sandpiper
Genus Calidris - sandpipers
Genus Coenocorypha - Austral snipes
Genus Gallinago
Genus Limnodromus - dowitchers
Genus Limosa - godwits
Genus Lymnocryptes - jack snipe
Genus Numenius - curlews
Genus Phalaropus - phalaropes
Genus Prosobonia - Polynesian sandpiper
Genus Scolopax
Genus Tringa
Genus Xenus - Terek sandpiper
Family Stercorariidae - skuas
Genus Stercorarius
Family Thinocoridae - seedsnipes
Genus Attagis
Genus Thinocorus
Family Turnicidae - buttonquails
Genus Ortyxelos
Genus Turnix
Ciconiiformes
Storks, openbills, and jabiru
Family Ciconiidae
Genus Anastomus - openbills
Genus Ciconia
Genus Ephippiorhynchus
Genus Jabiru
Genus Leptoptilos
Genus Mycteria
Coliiformes
Mousebirds
Family Coliidae
Genus Colius
Genus Urocolius
Columbiformes
Pigeons and doves
Family Columbidae
Genus Alectroenas - blue pigeons
Genus Alopecoenas
Genus Caloenas - Nicobar pigeon
Genus Chalcophaps - emerald doves
Genus Claravis
Genus Columba includes Aplopelia, Old World pigeons
Genus Columbina
Genus Cryptophaps - sombre pigeon
Genus Didunculus - tooth-billed pigeon
Genus Drepanoptila - possibly better merged with Ptilinopus
Genus Ducula - imperial pigeons
Genus Dysmoropelia - Saint Helena dove
Genus Gallicolumba
Genus Geopelia
Genus Geophaps
Genus Geotrygon - quail-doves
Genus Goura
Genus Gymnophaps - mountain pigeons
Genus Hemiphaga
Genus Henicophaps
Genus Leptotila
Genus Leptotrygon - olive-backed quail-dove
Genus Leucosarcia - wonga pigeon
Genus Lopholaimus - topknot pigeon
Genus Macropygia
Genus Metriopelia
Genus Nesoenas
Genus Ocyphaps - crested pigeon
Genus Oena - Namaqua dove, tentatively placed here
Genus Otidiphaps - pheasant pigeon
Genus Patagioenas - American pigeons
Genus Petrophassa - rock pigeons
Genus Phapitreron - brown dove
Genus Phaps
Genus Ptilinopus
Genus Reinwardtoena
Genus Starnoenas - blue-headed quail-dove
Genus Spilopelia
Genus Streptopelia - turtledoves
Genus Treron - green pigeons
Genus Trugon - thick-billed ground pigeon
Genus Turacoena
Genus Turtur - African wood doves, tentatively placed here
Genus Uropelia - long-tailed ground dove
Genus Zenaida - Zenaida doves
Genus Zentrygon
Coraciiformes
Rollers, bee eaters, todies, kingfishers, etc.
Family Alcedinidae - kingfishers
Genus Actenoides
Genus Alcedo
Genus Caridonax - glittering kingfisher
Genus Ceryle - pied kingfisher
Genus Ceyx
Genus Chloroceryle - American green kingfisher
Genus Cittura - lilac kingfisher
Genus Clytoceyx
Genus Corythornis
Genus Dacelo
Genus Halcyon
Genus Ispidina
Genus Lacedo
Genus Megaceryle
Genus Melidora - hook-billed kingfisher
Genus Pelargopsis
Genus Syma
Genus Tanysiptera - paradise kingfisher
Genus Todirhamphus
Family Brachypteraciidae - ground rollers
Genus Atelornis
Genus Brachypteracias - short-legged ground roller
Genus Geobiastes - scaly ground roller
Genus Uratelornis - long-tailed ground roller
Family Coraciidae - rollers
Genus Coracias
Genus Eurystomus
Family Meropidae - bee-eaters
Genus Meropogon - purple-bearded bee-eater
Genus Merops
Genus Nyctyornis
Family Momotidae - motmots
Genus Aspatha - blue-throated motmot
Genus Baryphthengus
Genus Electron
Genus Eumomota - turquoise-browed motmot
Genus Hylomanes - tody motmot
Genus Momotus
Family Todidae - todies
Genus Todus
Cuculiformes
Cuckoos, anis, etc.
Family Cuculidae
Genus Cacomantis
Genus Carpococcyx – Asian ground-cuckoos
Genus Centropus - coucals
Genus Cercococcyx – long-tailed cuckoos
Genus Ceuthmochares – yellowbills
Genus Chrysococcyx – bronze cuckoos
Genus Clamator
Genus Coccycua – formerly in Coccyzus and Piaya, includes Micrococcyx
Genus Coccyzus – includes Saurothera and Hyetornis
Genus Coua – coua
Genus Crotophaga – anis
Genus Cuculus – typical cuckoos
Genus Dromococcyx
Genus Eudynamys – typical koels
Genus Geococcyx – roadrunners
Genus Guira – guira cuckoo
Genus Hierococcyx – hawk-cuckoos
Genus Microdynamis – dwarf koel
Genus Morococcyx – lesser ground cuckoo
Genus Neomorphus – Neotropical ground-cuckoos
Genus Pachycoccyx – thick-billed cuckoo
Genus Phaenicophaeus – typical malkohas
Genus Piaya
Genus Rhinortha – Raffles's malkoha (sometimes in Phaenicophaeus; tentatively placed here)
Genus Scythrops – channel-billed cuckoo
Genus Surniculus – drongo-cuckoos
Genus Tapera – striped cuckoo
Genus Urodynamis – Pacific long-tailed cuckoo
Eurypygiformes
Sunbitterns and kagu
Family Eurypygidae - sunbittern
Genus Eurypyga
Family Rhynochetidae - kagu
Genus Rhynochetos
Falconiformes
Falcons and caracara
Family Falconidae
Genus Caracara – crested caracaras
Genus Daptrius – black caracara
Genus Falco – true falcons, hobbies and kestrels
Genus Herpetotheres – laughing falcon
Genus Ibycter – red-throated caracara (sometimes included in Daptrius)
Genus Micrastur – forest falcons
Genus Microhierax – typical falconets
Genus Milvago – brown caracaras
Genus Phalcoboenus – Andean and southern South American caracaras
Genus Polihierax – pygmy falcons
Genus Spiziapteryx – spot-winged falconet
Galliformes
Gamebirds
Family Cracidae
Genus Aburria
Genus Chamaepetes
Genus Crax - curassows
Genus Mitu - curassows
Genus Nothocrax - nocturnal curassow
Genus Oreophasis - horned guan
Genus Ortalis - chachalacas
Genus Papile - Piping guan
Genus Pauxi - helmeted curassows
Genus Penelope
Genus Penelopina
Family Megapodiidae
Genus Aepypodius
Genus Alectura - Australian brushturkey
Genus Eulipoa - Moluccan megapode
Genus Leipoa
Genus Macrocephalon - maleo
Genus Megapodius - scrubfowl
Genus Talegalla
Family Numididae
Genus Acryllium
Genus Agelastes
Genus Guttera
Genus Numida - helmeted guineafowl
Family Odontophoridae
Genus Callipepla
Genus Colinus
Genus Cyrtonyx
Genus Dactylortyx - singing quail
Genus Dendrortyx
Genus Odontophorus - wood quails
Genus Oreortyx - mountain quails
Genus Philortyx - banded quail
Genus Ptilopachus
Genus Rhynchortyx - tawny-faced quail
Family Phasianidae
Genus Afropavo - Congo peafowl
Genus Alectoris - rock partridges
Genus Ammoperdix - see-see and sand partridge
Genus Anurophasis - Snow Mountain quail
Genus Arborophila - hill partridge
Genus Argusianus - great argus
Genus Bambusicola - bamboo partridge
Genus Bonasa - ruffed grouse
Genus Caloperdix - ferruginous partridge
Genus Catreus - cheer pheasant
Genus Centrocercus - sage grouse
Genus Chrysolophus - ruffed pheasant
Genus Coturnix - mouse pheasant
Genus Crossoptilon - eared pheasant
Genus Dendragapus
Genus Excalfactoria
Genus Falcipennis
Genus Francolinus - true francolins
Genus Galloperdix - Indian spurfowl
Genus Gallus - junglefowl
Genus Haematortyx - crimson-headed partridge
Genus Ithaginis - blood pheasant
Genus Lagopus - ptarmigans
Genus Lerwa - snow partridge
Genus Lophophorus - monal
Genus Lophura - gallopheasants
Genus Margaroperdix - Madagascan partridge
Genus Melanoperdix - black partridge
Genus Meleagris - turkeys
Genus Ophrysia - Himalayan quail
Genus Pavo - peafowl
Genus Peliperdix
Genus Perdicula - bush quail
Genus Perdix - true partridges
Genus Phasianus - typical pheasants
Genus Polyplectron - peacock-pheasant
Genus Pternistis - African spurfowls
Genus Pucrasia - Koklass pheasant
Genus Rheinardia - crested argus
Genus Rhizothera
Genus Rollulus - crested partridge
Genus Scleroptila
Genus Synoicus - see Coturnix
Genus Syrmaticus - long-tailed pheasants
Genus Tetrao - capercaillies and black grouse
Genus Tetraogallus - snowcocks
Genus Tetraophasis - monal-partridge
Genus Tetrastes
Genus Tragopan - horned pheasant
Genus Tympanuchus - prairie chickens
Genus Xenoperdix - forest partridges
GaviiformesFamily Gaviidae Genus Gavia - loons
Gruiformes
Cranes, crakes, rails, wood-rails, fluftais, gallinules, limpkin, trumpeters, and finfoots Family Aramidae - limpkin
Genus Aramus Family Gruidae - cranes
Genus Antigone
Genus Balearica
Genus Grus - cranes
Genus Leucogeranus - Siberian crane Family Heliornithidae - finfoots
Genus Heliopais - masked finfoot
Genus Heliornis - sungrebe
Genus Podica - African finfoot Family Psophiidae Genus Psophia - trumpeters Family Rallidae - crakes, moorhens, gallinules, and rails
Genus Aenigmatolimnas - striped crake
Genus Amaurolimnas - uniform crake
Genus Amaurornis - bush-hens
Genus Anurolimnas
Genus Aramides
Genus Aramidopsis – snoring rail
Genus Atlantisia - Inaccessible Island rail
?Genus Biensis - Madagascan rails (synonym of Rallus?)
Genus Cabalus - Chatham rail
Genus Coturnicops - barred-backed crake
?Genus Creciscus - blackish crake
Genus Crecopsis – African crake
Genus Crex - corn crake
Genus Cyanolimnas – Zapata rail
Genus Diaphorapteryx - Hawkins's rail
Genus Dryolimnas
Genus Eulabeornis – chestnut rail
Genus Fulica - coots
Genus Gallicrex - watercock
Genus Gallinula - moorhens
Genus Gallirallus
Genus Gymnocrex - bare-faced rails
Genus Habroptila – invisible rail
Genus Hapalocrex - yellow-breasted crake
Genus Himantornis - Nkulengu rail
Genus Laterallus - ruddy crake
Genus Lewinia
?Genus Limnocrex (synonym of Laterallus?)
Genus Megacrex - New Guinea flightless rail
Genus Micropygia - ocellated crake
Genus Mundia - Ascension crake
Genus Mustelirallus
Genus Nesoclopeus
Genus Paragallinula - lesser moorhen
Genus Pardirallus
Genus Poliolimnas - see Amaurornis
Genus Porphyrio - swamphens
Genus Porphyriops – spot-flanked gallinule
Genus Porzana
Genus Rallicula - forest rails
Genus Rallina - chestnut rails
Genus Rallus
Genus Rougetius - Rouget's rail
Genus Rufirallus - russet-crowned crake
Genus Tribonyx - native-hens
Genus Zapornia - see Porzana Family Sarothruridae
Genus Canirallus - grey-throated rail and wood rails
Genus Sarothrura - flufftails
LeptosomiformesFamily LeptosomidaeGenus Leptosomus - cuckoo roller
MesitornithiformesFamily Mesitornithidae - mesites
Genus Mesitornis
Genus Monias - Subdesert mesite
Musophagiformes
Turacos and go-away-birdsFamily Musophagidae Genus Corythaeola - great blue turaco
Genus Corythaixoides - go-away-birds
Genus Crinifer - plantain-eaters
Genus Musophaga
Genus Ruwenzorornis - Rwenzori turaco
Genus Tauraco
OpisthocomiformesFamily Opisthocomidae Genus Opisthocomus - hoatzin
Otidiformes
Bustards, floricans, etc. Family Otididae Genus Afrotis
Genus Ardeotis
Genus Chlamydotis
Genus Eupodotis
Genus Houbaropsis - Bengal florican
Genus Lissotis
Genus Lophotis
Genus Neotis
Genus Otis - great bustard
Genus Sypheotides
Genus Tetrax - little bustard
Passeriformes
Passerines, the "song birds". This is the largest order of birds and contains more than half of all birds. Family Acanthisittidae Genus Acanthisitta - rifleman
Genus Xenicus - New Zealand wrens Family Acanthizidae - scrubwrens, thornbills, and gerygones
Genus Acanthiza – thornbill
Genus Acanthornis – scrubtit
Genus Aethomyias – scrubwrens
Genus Aphelocephala – whiteface
Genus Calamanthus – fieldwren
Genus Crateroscelis
Genus Gerygone
Genus Hylacola – heathwren
Genus Neosericornis – yellow-throated scrubwren
Genus Oreoscopus – fernwren
Genus Origma
Genus Pachycare – goldenface
Genus Pycnoptilus – pilotbird
Genus Pyrrholaemus - speckled warbler
Genus Sericornis – scrubwrens
Genus Smicrornis – weebill Family Acrocephalidae - marsh- and tree-warblers, recently split from the Sylviidae
Genus Acrocephalus
Genus Calamonastides - papyrus yellow warbler
Genus Chloropeta
Genus Hippolais
Genus Iduna
Genus Nesillas Family Aegithalidae - long-tailed tits or bushtits
Genus Aegithalos
Genus Leptopoecile
Genus Psaltriparus - American bushtit Family Aegithinidae Genus Aegithina - iora Family Alaudidae - larks
Genus Alaemon – hoopoe-lark
Genus Alauda – skylark
Genus Alaudala
Genus Ammomanes
Genus Ammomanopsis – Gray's lark
Genus Calandrella – short-toed lark
Genus Calendulauda
Genus Certhilauda – short-clawed lark and long-billed lark
Genus Chersomanes – spike-heeled lark
Genus Chersophilus – Dupont's lark
Genus Eremalauda – Dunn's lark
Genus Eremophila – horned lark
Genus Eremopterix – sparrow-larks
Genus Galerida – Large-billed lark and crested lark
Genus Heteromirafra – Rudd's lark and Archer's lark
Genus Lullula – woodlark
Genus Melanocorypha
Genus Mirafra – larks and bushlarks
Genus Pinarocorys – dusky lark and rufous-rumped lark
Genus Ramphocoris – thick-billed lark
Genus Spizocorys Family Artamidae - woodswallows, butcherbirds, currawongs, and Australian magpie
Genus Artamus - woodswallows
Genus Cracticus
Genus Gymnorhina - Australian magpie
Genus Melloria - black butcherbird
Genus Peltops
Genus Strepera - currawongs Family Atrichornithidae Genus Atrichornis - scrub-birds Family Bernieridae - Malagasy warblers, a newly assembled family
Genus Bernieria – Madagascan warbler
Genus Crossleyia – Madagascan yellowbrow
Genus Cryptosylvicola – cryptic warbler
Genus Hartertula – wedge-tailed jery
Genus Oxylabes – white-throated oxylabes
Genus Randia – Rand's warbler
Genus Thamnornis – Thamnornis
Genus Xanthomixis Family Bombycillidae Genus Bombycilla - waxwings Family Buphagidae Genus Buphagus - oxpeckers. Formerly usually included in Sturnidae. Family Calcariidae - longspurs and snow buntings
Genus Calcarius - longspurs
Genus Plectrophenax - snow and McKay's buntings
Genus Rhynchophanes - thick-billed longspur Family Callaeidae - New Zealand wattlebirds
Genus Callaeas - kokako
Genus Heteralocha - huia
Genus Philesturnus - saddleback Family Calyptophilidae Genus Calyptophilus - chat-tanagers Family Campephagidae - cuckooshrikes and trillers
Genus Campephaga
Genus Campochaera - golden cuckooshrike
Genus Ceblepyris
Genus Celebesica - pygmy cuckooshrike
Genus Coracina
Genus Cyanograucalus - blue cuckooshrike
Genus Edolisoma
Genus Lalage
Genus Lobotos
Genus Malindangia - McGregor's cuckooshrike
Genus Pericrocotus - minivet Family Cardinalidae - cardinals and allies
Genus Amaurospiza
Genus Cardinalis
Genus Caryothraustes
Genus Chlorothraupis
Genus Cyanocompsa
Genus Cyanoloxia - Glaucous-blue grosbeak
Genus Granatellus
Genus Habia
Genus Passerina
Genus Periporphyrus - red-and-black grosbeak
Genus Pheucticus
Genus Piranga
Genus Rhodothraupis - crimson-collared grosbeak
Genus Spiza - dickcissel Family Certhiidae - treecreepers
Genus Certhia
Genus Salpornis Family Cettiidae - ground-warblers and allies, recently split from the Sylviidae
Genus Abroscopus – abroscopus warbler
Genus Cettia – typical bush warblers
Genus Horornis
Genus Hylia – green hylia (tentatively placed here)
Genus Pholidornis – tit hylia (formerly in Remizidae; tentatively placed here)
Genus Phyllergates
Genus Tesia
Genus Tickellia – broad-billed warbler
Genus Urosphena – stubtails Family Chaetopidae Genus Chaetops - rockjumpers, recently split from the Turdidae Family Chloropseidae Genus Chloropsis - leafbirds Family Cinclidae Genus Cinclus - dippers Family Cisticolidae - cisticolas and allies
Genus Apalis
Genus Artisornis
Genus Bathmocercus - rufous warblers
Genus Calamonastes
Genus Camaroptera
Genus Cisticola
Genus Drymocichla - red-winged grey warbler
Genus Eminia - grey-capped warbler
Genus Eremomela
Genus Euryptila - cinnamon-breasted warbler
Genus Heliolais – red-winged warbler (Sometimes placed in Prinia)
Genus Hypergerus - oriole warbler
Genus Incana - Socotra warbler
Genus Malcorus - rufous-eared warbler
Genus Micromacronus
Genus Neomixis - Jerys (genus is basal to all other Cisticolidae)
Genus Oreolais (moved here from Apalis)
Genus Oreophilais - Roberts's warbler
Genus Orthotomus - tailorbirds
Genus Phragmacia - Namaqua warbler
Genus Phyllolais - buff-bellied warbler
Genus Poliolais - white-tailed warbler
Genus Prinia
Genus Scepomycter (sometimes merged into Bathmocercus)
Genus Schistolais
Genus Spiloptila - cricket warbler
Genus Urolais - green longtail
Genus Urorhipis– sometimes placed in Prinia Family Climacteridae - Australian treecreeper
Genus Cormobates
Genus Climacteris Family Cnemophilidae - satinbirds
Genus Cnemophilus
Genus Loboparadisea - yellow-breasted satinbird Family Conopophagidae - gnateaters and gnatpittas
Genus Conopophaga
Genus Pittasoma Family Corcoracidae - Australian mudnester
Genus Corcorax - white-winged chough
Genus Struthidea - apostlebird Family Corvidae - crows, ravens, and jays
Genus Aphelocoma – scrub jays
Genus Calocitta – Magpie-jay
Genus Cissa - magpies
Genus Corvus - crows and ravens
Genus Crypsirina - treepies
Genus Cyanocitta - jays
Genus Cyanocorax - jays
Genus Cyanolyca
Genus Cyanopica - magpies
Genus Dendrocitta - treepies
Genus Garrulus - jays
Genus Gymnorhinus - pinyon jay
Genus Nucifraga - nutcrackers
Genus Perisoreus - jays
Genus Pica - magpies
Genus Platylophu - Crested jay
Genus Platysmurus - black magpie
Genus Podoces – ground jays
Genus Psilorhinus - brown jay
Genus Ptilostomus - piapiac
Genus Pyrrhocorax - chough
Genus Temnurus - ratchet-tailed treepie
Genus Urocissa - blue magpies
Genus Zavattariornis - Stresemann's bushcrow Family Cotingidae - cotingas and allies
Genus Ampelioides - scaled fruiteater
Genus Ampelion
Genus Carpodectes
Genus Carpornis - berryeaters
Genus Cephalopterus - umbrellabirds
Genus Conioptilon - black-faced cotinga
Genus Cotinga
Genus Doliornis
Genus Gymnoderus - bare-necked fruitcrow
Genus Haematoderus - crimson fruitcrow
Genus Lipaugus
Genus Perissocephalus - capuchinbird
Genus Phibalura - swallow-tailed cotinga
Genus Phoenicircus
Genus Phytotoma - plantcutters
Genus Pipreola
Genus Porphyrolaema - purple-throated cotinga
Genus Procnias - Neotropical bellbird
Genus Pyroderus - red-ruffed fruitcrow
Genus Querula - purple-throated fruitcrow
Genus Rupicola
Genus Snowornis
Genus Tijuca
Genus Xipholena
Genus Zaratornis - white-cheeked cotinga Family Dasyornithidae Genus Dasyornis - bristlebirds (formerly in Acanthizidae) Family Dicaeidae - flowerpeckers (sunbirds and flowerpeckers, might be included in Passeroidea)
Genus Dicaeum
Genus Prionochilus Family Dicruridae Genus Dicrurus - drongos Family Donacobiidae Genus Donacobius - black-capped donacobius (previously classed as a wren, but probably closest to the Locustellidae or Bernieridae) Family Dulidae (tentatively placed here)
Genus Dulus- palmchat Family Elachuridae Genus Elachura - spotted elachura Family Emberizidae Genus Diglossopis
Genus Emberiza - Old World buntings Family Erythrocercidae Genus Erythrocercus Family Estrildidae - estrildid finches (waxbills, munias, and allies)
Genus Amadina - cut-throats
Genus Amandava - avadavats
Genus Clytospiza - brown twinspot
Genus Coccopygia
Genus Cryptospiza - crimsonwings
Genus Emblema - painted finch
Genus Erythrura - parrotfinches (includes Chloebia)
Genus Estrilda - waxbills
Genus Euodice - silverbill
Genus Euschistospiza
Genus Heteromunia - pictorella mannikin
Genus Hypargos
Genus Lagonosticta - firefinches
Genus Lonchura - Munias, mannikins, and silverbills
Genus Mandingoa - green-backed twinspot
Genus Neochmia
Genus Nesocharis - oliveback
Genus Nigrita
Genus Odontospiza - grey-headed silverbill
Genus Oreostruthus - mountain firetail
Genus Ortygospiza - quailfinches
Genus Padda
Genus Paludipasser - locust finch
Genus Parmoptila - antpeckers
Genus Poephila
Genus Pyrenestes - seedcrackers
Genus Pytilia
Genus Spermophaga - bluebill
Genus Stagonopleura - firetail
Genus Taeniopygia
Genus Uraeginthus Family Eulacestomidae Genus Eulacestoma - wattled ploughbill Family Eupetidae Genus Eupetes - Malaysian rail-babbler (recently split from the Cinclosomatidae) Family Eurylaimidae - broadbills
Genus Calyptomena
Genus Corydon - dusky broadbill
Genus Cymbirhynchus - black-and-red broadbill
Genus Eurylaimus
Genus Neodrepanis
Genus Philepitta
Genus Psarisomus - long-tailed broadbill
Genus Pseudocalyptomena - Grauer's broadbill
Genus Sarcophanops
Genus Serilophus - silver-breasted broadbill
Genus Smithornis Family Formicariidae - Antthrushe
Genus Chamaeza
Genus Formicarius Family Fringillidae - true finches and Hawaiian honeycreepers. (Possibly polyphyletic)
Genus Acanthis – redpolls
Genus Agraphospiza – Blanford's rosefinch
Genus Bucanetes – trumpeter finch and Mongolian finch
Genus Callacanthis – spectacled finch
Genus Carduelis
Genus Carpodacus – rosefinches
Genus Chloridops
Genus Chloris – greenfinches
Genus Chlorodrepanis - 'amakihis
Genus Chlorophonia
Genus Chrysocorythus – mountain serin
Genus Coccothraustes
Genus Crithagra
Genus Drepanis
Genus Eophona – Chinese grosbeak and Japanese grosbeak
Genus Euphonia
Genus Fringilla
Genus Haemorhous – American rosefinches
Genus Hemignathus
Genus Himatione
Genus Leucosticte – mountain and rosy finches
Genus Linaria
Genus Linurgus – oriole finch
Genus Loxia – crossbills
Genus Loxioides – palila
Genus Loxops
Genus Magumma – ʻanianiau
Genus Melamprosops – poʻouli
Genus Mycerobas – Palearctic grosbeaks
Genus Oreomystis – ʻakikiki
Genus Palmeria – ʻakohekohe
Genus Paroreomyza
Genus Pinicola – pine grosbeak
Genus Procarduelis – dark-breasted rosefinch
Genus Pseudonestor – Maui parrotbill
Genus Psittirostra – ʻŌʻū
Genus Pyrrhoplectes – golden-naped finch
Genus Pyrrhula – bullfinches
Genus Rhodopechys
Genus Rhodospiza – desert finch
Genus Rhynchostruthus – golden-winged grosbeak
Genus Serinus
Genus Spinus
Genus Telespiza Family Furnariidae - ovenbirds and woodcreepers
Genus Acrobatornis – pink-legged graveteiro
Genus Anabacerthia – foliage-gleaners
Genus Anabazenops – foliage-gleaners
Genus Ancistrops – chestnut-winged hookbill
Genus Anumbius – firewood-gatherer
Genus Aphrastura – rayaditos
Genus Asthenes – canasteros
Genus Automolus – foliage-gleaners
Genus Berlepschia – point-tailed palmcreeper
Genus Campylorhamphus – scythebills
Genus Certhiasomus – spot-throated woodcreeper (also described as Deconychura stictolaema)
Genus Certhiaxis – spinetails
Genus Cichlocolaptes
Genus Cinclodes
Genus Clibanornis
Genus Coryphistera – lark-like brushrunner
Genus Cranioleuca – typical spinetails
Genus Deconychura – long-tailed woodcreeper
Genus Dendrexetastes – cinnamon-throated woodcreeper
Genus Dendrocincla – woodcreepers
Genus Dendrocolaptes – woodcreepers
Genus Dendroplex – straight-billed woodcreeper (formerly in Xiphorhynchus)
Genus Drymornis – scimitar-billed woodcreeper
Genus Drymotoxeres – greater scythebill
Genus Furnarius – horneros
Genus Geocerthia – striated earthcreeper (also described as Upucerthia serrana)
Genus Geositta – miners
Genus Glyphorynchus – wedge-billed woodcreeper
Genus Heliobletus – sharp-billed treehunter
Genus Hellmayrea – white-browed spinetail
Genus Hylexetastes – woodcreepers
Genus Lepidocolaptes – narrow-billed woodcreeper
Genus Leptasthenura – tit-spinetails
Genus Limnoctites – straight-billed reedhaunter (sometimes included in Limnornis, but closer to, and possibly better merged with Cranioleuca)
Genus Limnornis – curve-billed reedhaunter
Genus Lochmias – sharp-tailed streamcreeper
Genus Margarornis – treerunners
Genus Mazaria – white-bellied spinetail
Genus Megaxenops – great xenops
Genus Metopothrix – orange-fronted plushcrown
Genus Microxenops – rufous-tailed xenops
Genus Nasica – long-billed woodcreeper
Genus Ochetorhynchus – earthcreepers (formerly included in Upucerthia) (includes Chilia)
Genus Phacellodomus – Thornbird
Genus Philydor – foliage-gleaners
Genus Phleocryptes – wren-like rushbird
Genus Premnoplex – typical barbtails
Genus Premnornis – rusty-winged barbtail
Genus Pseudasthenes – "false" canasteros
Genus Pseudocolaptes – tuftedcheeks
Genus Pseudoseisura
Genus Pygarrhichas – white-throated treerunner
Genus Roraimia -
Genus Schoeniophylax – Chotoy spinetail
Genus Sclerurus – leaftossers
Genus Siptornis – spectacled prickletail
Genus Sittasomus – olivaceous woodcreeper
Genus Spartonoica – bay-capped wren-spinetail
Genus Sylviorthorhynchus – Des Murs's wiretail
Genus Synallaxis – spinetails
Genus Syndactyla – foliage-gleaners
Genus Tarphonomus (new genus for 2 species formerly included in Upucerthia)
Genus Thripadectes – treehunters
Genus Thripophaga – softtails
Genus Upucerthia – earthcreepers
Genus Xenerpestes – greytails
Genus Xenops
Genus Xiphocolaptes – woodcreepers
Genus Xiphorhynchus – woodcreepers (possibly polyphyletic) Family Grallariidae - antpittas
Genus Grallaria
Genus Grallaricula
Genus Hylopezus
Genus Myrmothera Family Hirundinidae - swallows and martins
Genus Alopochelidon - tawny-headed swallow
Genus Atticora
Genus Cecropis
Genus Cheramoeca - white-backed swallow
Genus Delichon
Genus Haplochelidon - Andean swallow
Genus Hirundo
Genus Neochelidon - white-thighed swallow
Genus Notiochelidon
Genus Petrochelidon
Genus Phedina
Genus Progne
Genus Psalidoprocne - saw-wings
Genus Pseudhirundo - grey-rumped swallow
Genus Pseudochelidon - river martin
Genus Ptyonoprogne - crag martins
Genus Riparia
Genus Stelgidopteryx
Genus Tachycineta Family Hyliidae - newly proposed for genera currently in other families Family Hyliotidae Genus Hyliota - hyliotas (recently split from the Sylviidae) Family Hypocoliidae Genus Hypocolius - grey hypocolius (tentatively placed here) Family Icteridae - grackles, New World blackbirds, and New World orioles
Genus Agelaioides - baywings
Genus Agelaius – typical American blackbirds
Genus Agelasticus
Genus Amblycercus – yellow-billed cacique
Genus Amblyramphus – scarlet-headed blackbird
Genus Anumara - Forbes's blackbird
Genus Cacicus – true caciques
Genus Chrysomus
Genus Curaeus - Austral blackbird
Genus Dives
Genus Dolichonyx – bobolink
Genus Euphagus
Genus Gnorimopsar – chopi blackbird
Genus Gymnomystax – oriole blackbird
Genus Hypopyrrhus – red-bellied grackle
Genus Icterus – New World orioles
Genus Lampropsar – velvet-fronted grackle
Genus Leistes – South American meadowlarks
Genus Macroagelaius
Genus Molothrus – cowbirds
Genus Nesopsar – Jamaican blackbird
Genus Oreopsar – Bolivian blackbird
Genus Psarocolius – oropendolas
Genus Pseudoleistes – marshbirds
Genus Quiscalus – grackles
Genus Sturnella – North American meadowlarks
Genus Xanthocephalus – yellow-headed blackbird
Genus Xanthopsar - saffron-cowled blackbird Family Ifritidae Genus Ifrita - blue-capped ifrit Family Irenidae Genus Irena - fairy-bluebirds Family Laniidae - shrikes
Genus Corvinella - yellow-billed shrike
Genus Eurocephalus
Genus Lanius
Genus Urolestes - magpie shrike Family Leiothrichidae - laughingthrushes and allies
Genus Actinodura – barwings
Genus Argya (species previous placed in Turdoides)
Genus Cutia
Genus Garrulax – laughingthrushes
Genus Grammatoptila - striated laughingthrush
Genus Heterophasia - sibia
Genus Ianthocincla – laughingthrushes (species previous placed in Garrulax)
Genus Laniellus – crocias
Genus Leioptila - rufous-backed sibia
Genus Leiothrix
Genus Liocichla
Genus Minla - red-tailed minla
Genus Montecincla – laughingthrushes
Genus Pterorhinus (species previous placed in Garrulax)
Genus Trochalopteron – laughingthrushes
Genus Turdoides – babblers Family Locustellidae - grass-warbler and allies, recently split from the Sylviidae
Genus Bradypterus – megalurid bush warblers
Genus Catriscus – fan-tailed grassbird
Genus Cincloramphus - buff-banded thicketbird
Genus Elaphrornis – Sri Lanka bush warbler
Genus Helopsaltes – grasshopper warbler
Genus Locustella – grass warblers
Genus Malia
Genus Megalurus – striated grassbird
Genus Poodytes
Genus Robsonius – ground warblers
Genus Schoenicola Family Machaerirhynchidae Genus Machaerirhynchus - boatbills Family Macrosphenidae - African warblers such as longbills and crombecs, a recently proposed family whose composition is still uncertain
Genus Achaetops - rockrunner
Genus Cryptillas – Victorin's warbler (formerly Bradypterus)
Genus Macrosphenus – longbills
Genus Melocichla - moustached grass warbler
Genus Sphenoeacus - Cape grassbird
Genus Sylvietta – crombecs Family Malaconotidae - puffbacks, bushshrikes, tchagras, boubous, and allies
Genus Chlorophoneus
Genus Dryoscopus
Genus Laniarius
Genus Malaconotus
Genus Nilaus - brubru
Genus Rhodophoneus - rosy-patched bushshrike
Genus Tchagra
Genus Telophorus Family Maluridae - fairywrens, emu-wren, and grasswrens
Genus Amytornis – grasswrens
Genus Chenorhamphus
Genus Clytomyias – orange-crowned fairywren
Genus Malurus
Genus Sipodotus – Wallace's fairywren
Genus Stipiturus – emu-wren Family Melampittidae Genus Megalampitta - greater melampitta
Genus Melampitta Family Melanocharitidae - berrypeckers and longbills
Genus Melanocharis
Genus Oedistoma
Genus Rhamphocharis - spotted berrypecker
Genus Toxorhamphus Family Melanopareiidae Genus Melanopareia - crescentchests Family Meliphagidae - honeyeaters
Genus Acanthagenys - spiny-cheeked honeyeater
Genus Acanthorhynchus - spinebill
Genus Anthochaera
Genus Anthornis - New Zealand bellbird
Genus Ashbyia - gibberbird
Genus Bolemoreus
Genus Caligavis
Genus Certhionyx - pied honeyeater
Genus Cissomela - banded honeyeater
Genus Conopophila
Genus Entomyzon - blue-faced honeyeater
Genus Epthianura
Genus Foulehaio - wattled honeyeater
Genus Gavicalis
Genus Gliciphila - tawny-crowned honeyeater
Genus Glycichaera - green-backed honeyeater
Genus Glycifohia
Genus Grantiella
Genus Guadalcanaria - Guadalcanal honeyeater
Genus Gymnomyza
Genus Lichenostomus
Genus Lichmera
Genus Macgregoria - MacGregor's honeyeater
Genus Manorina
Genus Meliarchus - makira honeyeater
Genus Melidectes
Genus Melilestes - long-billed honeyeater
Genus Meliphaga
Genus Melipotes
Genus Melithreptus
Genus Melitograis - white-streaked friarbird
Genus Myza
Genus Myzomela
Genus Nesoptilotis
Genus Oreornis - orange-cheeked honeyeater
Genus Philemon - friarbird
Genus Phylidonyris
Genus Plectorhyncha - striped honeyeater
Genus Prosthemadera - tui
Genus Ptiloprora
Genus Ptilotula
Genus Purnella - white-fronted honeyeater
Genus Pycnopygius
Genus Ramsayornis
Genus Stomiopera
Genus Stresemannia - Bougainville honeyeater
Genus Sugomel - black honeyeater
Genus Timeliopsis
Genus Trichodere - white-streaked honeyeater
Genus Xanthotis Family Menuridae Genus Menura - lyrebirds Family Mimidae - mockingbirds and thrashers
Genus Allenia - scaly-breasted thrasher
Genus Cinclocerthia - tremblers
Genus Dumetella - grey catbird
Genus Margarops - pearly-eyed thrasher
Genus Melanoptila - black catbird
Genus Melanotis
Genus Mimus (includes Nesomimus)
Genus Oreoscoptes - sage thrasher
Genus Ramphocinclus - white-breasted thrasher
Genus Toxostoma Family Mitrospingidae Genus Lamprospiza - Red-billed pied tanager
Genus Mitrospingus
Genus Orthogonys - Olive-green tanager Family Modulatricidae - dapple-throat and allies (sometimes Arcanatoridae)
Genus Arcanator - dapple-throat
Genus Kakamega
Genus Modulatrix - spot-throat Family Mohouidae Genus Mohoua Family Monarchidae - monarch flycatchers
Genus Arses
Genus Carterornis
Genus Chasiempis - ‘elepaio
Genus Clytorhynchus – shrikebill
Genus Eutrichomyias – cerulean paradise flycatcher
Genus Grallina – magpie-larks
Genus Hypothymis
Genus Mayrornis
Genus Metabolus – Chuuk monarch
Genus Monarcha
Genus Myiagra – broad-billed flycatcher
Genus Neolalage – buff-bellied monarch
Genus Pomarea
Genus Symposiachrus
Genus Terpsiphone – paradise flycatcher
Genus Trochocercus Family Motacillidae Genus Anthus - pipits
Genus Dendronanthus - forest wagtail
Genus Hemimacronyx (proposed)
Genus Macronyx - longclaws
Genus Motacilla - wagtails
Genus Tmetothylacus - golden pipit Family Muscicapidae - Old World flycatchers and chats. (Monophyly needs confirmation)
Genus Alethe
Genus Anthipes
Genus Brachypteryx – shortwings
Genus Calliope
Genus Campicoloides – buff-streaked chat
Genus Cercotrichas – scrub robins
Genus Chamaetylas
Genus Cichladusa – palm thrush
Genus Cinclidium – blue-fronted robin
Genus Copsychus – magpie-robins and shamas
Genus Cossypha – robin-chats
Genus Cossyphicula – white-bellied robin-chat
Genus Cyanoptila
Genus Cyornis
Genus Emarginata
Genus Empidornis – silverbirds
Genus Enicurus – forktails
Genus Erithacus – European robin
Genus Eumyias
Genus Ficedula – flycatchers
Genus Fraseria – forest flycatchers
Genus Heinrichia – great shortwing
Genus Heteroxenicus – Gould's shortwing
Genus Humblotia – Humblot's flycatcher
Genus Irania – white-throated robin
Genus Larvivora
Genus Leonardina – Bagobo babbler
Genus Luscinia
Genus Melaenornis
Genus Monticola – rock thrushes
Genus Muscicapa
Genus Muscicapella – pygmy flycatcher
Genus Myiomela
Genus Myioparus – tit-flycatchers
Genus Myophonus – whistling thrush
Genus Myrmecocichla
Genus Namibornis – Herero chat
Genus Niltava
Genus Oenanthe – wheatears
Genus Phoenicurus – redstarts
Genus Pinarochroa – moorland chat
Genus Pinarornis – boulder chat
Genus Pogonocichla – white-starred robin
Genus Saxicola
Genus Sheppardia – akalats
Genus Sholicola
Genus Stiphrornis – forest robins
Genus Swynnertonia – Swynnerton's robin
Genus Tarsiger
Genus Thamnolaea – cliff chats
Genus Vauriella Family Nectariniidae - sunbirds and spiderhunters
Genus Aethopyga
Genus Anabathmis (sometimes included in Nectarinia)
Genus Anthobaphes - orange-breasted sunbird (sometimes included in Nectarinia)
Genus Anthreptes
Genus Arachnothera - spiderhunters
Genus Chalcomitra (sometimes included in Nectarinia)
Genus Chalcoparia - Ruby-cheeked sunbird (sometimes included in Anthreptes)
Genus Cinnyris (sometimes included in Nectarinia)
Genus Cyanomitra (sometimes included in Nectarinia)
Genus Deleornis (sometimes included in Anthreptes)
Genus Drepanorhynchus - golden-winged sunbird (sometimes included in Nectarinia)
Genus Dreptes - giant sunbird (sometimes included in Nectarinia)
Genus Hedydipna (sometimes included in Anthreptes)
Genus Hypogramma - purple-naped sunbird
Genus Leptocoma (sometimes included in Nectarinia)
Genus Nectarinia Family Neosittidae Genus Daphoenositta - sittellas Family Nesospingidae Genus Nesospingus - Puerto Rican tanager Family Nicatoridae
Genus Nicator- nicators Family Notiomystidae Genus Notiomystis - stitchbirds Family Oreoicidae - Australo-Papuan bellbirds
Genus Aleadryas - rufous-naped bellbird
Genus Oreoica - crested bellbird
Genus Ornorectes - piping bellbird Family Oriolidae''' - Old World orioles
Genus Oriolus – orioles
Genus Pitohui Genus Sphecotheres – figbirds Family Orthonychidae Genus Orthonyx - logrunners Family Pachycephalidae Genus Colluricincla - shrikethrushes
Genus Coracornis
Genus Falcunculus – crested shriketit
Genus Melanorectes – black pitohui
Genus Pachycephala – whistlers
Genus Pseudorectes Family Panuridae Genus Panurus - bearded reedling (formerly classed as a parrotbill) Family Paradisaeidae - birds-of-paradise
Genus Astrapia
Genus Cicinnurus - king bird-of-paradise
Genus Diphyllodes
Genus Drepanornis
Genus Epimachus
Genus Lophorina
Genus Lycocorax - paradise-crow
Genus Manucodia - manucodes
Genus Paradigalla
Genus Paradisaea
Genus Parotia
Genus Phonygammus - trumpet manucode
Genus Pteridophora - King of Saxony bird-of-paradise
Genus Ptiloris
Genus Seleucidis - twelve-wired bird-of-paradise
Genus Semioptera - standardwings Family Paramythiidae - painted berrypeckers
Genus Oreocharis - tit berrypecker
Genus Paramythia - crested berrypecker Family Pardalotidae Genus Pardalotus - pardalotes Family Paridae - Tits, chickadees, and titmice
Genus Baeolophus
Genus Cephalopyrus - fire-capped tit
Genus Cyanistes
Genus Lophophanes
Genus Machlolophus
Genus Melaniparus
Genus Melanochlora - sultan tit
Genus Pardaliparus
Genus Parus
Genus Periparus
Genus Poecile
Genus Pseudopodoces - ground tit
Genus Sittiparus
Genus Sylviparus - yellow-browed tit Family Parulidae - New World warblers
Genus Basileuterus
Genus Cardellina
Genus Catharopeza - whistling warbler
Genus Ergaticus
Genus Geothlypis - yellowthroats
Genus Helmitheros - worm-eating warbler
Genus Leucopeza - Semper's warbler
Genus Limnothlypis - Swainson's warbler
Genus Mniotilta - black-and-white warbler
Genus Myioborus - whitestarts
Genus Myiothlypis
Genus Oporornis - Connecticut warbler
Genus Oreothlypis
Genus Parkesia - waterthrushes
Genus Parula
Genus Protonotaria - prothonotary warbler
Genus Seiurus - ovenbird
Genus Setophaga
Genus Vermivora Family Passerellidae - New World sparrows
Genus Aimophila
Genus Ammodramus
Genus Amphispiza
Genus Arremon
Genus Arremonops
Genus Artemisiospiza
Genus Atlapetes
Genus Calamospiza - lark bunting
Genus Chlorospingus (traditionally placed in the tanager family Thraupidae)
Genus Chondestes - lark sparrow
Genus Junco
Genus Melospiza
Genus Melozone
Genus Oreothraupis - tanager finch
Genus Oriturus - striped sparrow
Genus Passerculus
Genus Passerella - fox sparrow
Genus Peucaea
Genus Pezopetes - large-footed finch
Genus Pipilo - Towhee
Genus Pooecetes - vesper sparrow
Genus Pselliophorus
Genus Spizella
Genus Spizelloides - American tree sparrow
Genus Torreornis - Zapata sparrow
Genus Xenospiza - Sierra Madre sparrow
Genus Zonotrichia Family Passeridae - Old World sparrows
Genus Carpospiza - pale rockfinch
Genus Gymnoris
Genus Hypocryptadius - cinnamon ibon
Genus Montifringilla
Genus Onychostruthus - white-rumped snowfinch
Genus Passer
Genus Petronia - rock sparrows
Genus Pyrgilauda Family Pellorneidae - jungle babblers
Genus Alcippe
Genus Gampsorhynchus
Genus Graminicola
Genus Illadopsis
Genus Jabouilleia
Genus Kenopia - striped wren-babbler
Genus Laticilla
Genus Malacocincla
Genus Malacopteron
Genus Napothera
Genus Pellorneum
Genus Ptilocichla
Genus Ptyrticus - spotted thrush-babbler
Genus Rimator
Genus Trichastoma Family Petroicidae - Australasian robins
Genus Amalocichla
Genus Drymodes
Genus Eopsaltria
Genus Eugerygone - garnet robin
Genus Heteromyias
Genus Melanodryas
Genus Microeca
Genus Monachella - torrent flyrobin
Genus Pachycephalopsis
Genus Peneoenanthe - mangrove robin
Genus Peneothello
Genus Petroica
Genus Poecilodryas
Genus Tregellasia Family Peucedramidae Genus Peucedramus - olive warbler Family Phaenicophilidae Genus Microligea - Green-tailed warbler
Genus Phaenicophilus
Genus Xenoligea - White-winged warbler Family Philepittidae - asities
Genus Neodrepanis
Genus Philepitta Family Phylloscopidae - leaf-warblers and allies (recently split from the Sylviidae)
Genus Phylloscopus - leaf warblers
Genus Seicercus Family Picathartidae Genus Picathartes - rockfowl Family Pipridae - manakins
Genus Antilophia
Genus Ceratopipra
Genus Chiroxiphia
Genus Chloropipo
Genus Corapipo
Genus Cryptopipo - green manakin
Genus Heterocercus
Genus Ilicura - pin-tailed manakin
Genus Lepidothrix
Genus Machaeropterus
Genus Manacus
Genus Masius - golden-winged manakin
Genus Neopelma
Genus Pipra
Genus Pseudopipra - white-crowned manakin
Genus Tyranneutes
Genus Xenopipo Family Pittidae - pittas
Genus Erythropitta
Genus Hydrornis
Genus Pitta Family Pityriaseidae Genus Pityriasis - Bornean bristlehead (tentatively placed here) Family Platysteiridae - wattle-eyes and relatives (formerly in Passerida, probably paraphyletic)
Genus Batis
Genus Lanioturdus - white-tailed shrike
Genus Platysteira Family Ploceidae - weavers
Genus Amblyospiza – thick-billed weaver
Genus Anaplectes – red-headed weaver
Genus Brachycope – bob-tailed weaver
Genus Bubalornis
Genus Dinemellia – white-headed buffalo weaver
Genus Euplectes – bishops and widowbirds
Genus Foudia – fody
Genus Histurgops – rufous-tailed weaver
Genus Malimbus
Genus Philetairus – sociable weaver
Genus Plocepasser – sparrow-weavers
Genus Ploceus
Genus Pseudonigrita
Genus Quelea
Genus Sporopipes Family Pnoepygidae Genus Pnoepyga - pygmy wren-babbler Family Polioptilidae - gnatcatchers
Genus Microbates
Genus Ramphocaenus
Genus Polioptila Family Pomatostomidae - Australo-Papuan babblers
Genus Pomatostomus Family Prionopidae - see Vangidae Family Promeropidae Genus Promerops - sugarbirds Family Prunellidae Genus Prunella - accentors Family Psophodidae Genus Androphobus - Papuan whipbird
Genus Cinclosoma – quail-thrushes
Genus Psophodes
Genus Ptilorrhoa – jewel-babblers Family Ptiliogonatidae - silky flycatchers (tentatively placed here)
Genus Phainopepla
Genus Phainoptila - black-and-yellow phainoptila
Genus Ptilogonys Family Ptilonorhynchidae - bowerbirds
Genus Ailuroedus
Genus Amblyornis
Genus Archboldia
Genus Chlamydera
Genus Prionodura - golden bowerbird
Genus Ptilonorhynchus - satin bowerbird
Genus Scenopooetes - tooth-billed bowerbird
Genus Sericulus Family Pycnonotidae - bulbuls
Genus Acritillas – yellow-browed bulbul
Genus Alophoixus
Genus Andropadus – sombre greenbul
Genus Arizelocichla
Genus Atimastillas – yellow-throated leaflove
Genus Baeopogon
Genus Bleda – bristlebills
Genus Calyptocichla – golden greenbul
Genus Cerasophila – white-headed bulbul
Genus Chlorocichla
Genus Criniger
Genus Eurillas
Genus Hemixos
Genus Hypsipetes
Genus Iole
Genus Ixonotus – spotted greenbul
Genus Ixos
Genus Neolestes – black-collared bulbul
Genus Nok – bare-faced bulbul
Genus Phyllastrephus
Genus Pycnonotus
Genus Setornis – hook-billed bulbul
Genus Spizixos – finchbills
Genus Stelgidillas – slender-billed greenbul
Genus Thapsinillas - golden bulbul
Genus Thescelocichla – swamp palm bulbul
Genus Tricholestes – hairy-backed bulbul Family Regulidae Genus Regulus - kinglets Family Remizidae - penduline tits (sometimes included in the Paridae)
Genus Anthoscopus
Genus Auriparus - verdin
Genus Remiz Family Rhagologidae Genus Rhagologus - mottled berryhunter Family Rhinocryptidae - tapaculos
Genus Acropternis - ocellated tapaculo
Genus Eleoscytalopus
Genus Eugralla - ochre-flanked tapaculo
Genus Liosceles - rusty-belted tapaculo
Genus Merulaxis
Genus Myornis - ash-colored tapaculo
Genus Psilorhamphus - spotted bamboowren
Genus Pteroptochos
Genus Rhinocrypta - crested gallito
Genus Scelorchilus
Genus Scytalopus
Genus Teledromas - sandy gallito Family Rhipiduridae - fantails
Genus Chaetorhynchus – drongo fantail
Genus Lamprolia – silktail
Genus Rhipidura – fantails Family Rhodinocichlidae Genus Rhodinocichla - Rosy thrush-tanager Family Salpornithidae Genus Salpornis - spotted creepers (Tentatively placed here; often considered a subfamily of the Certhidae) Family Sapayoidae Genus Sapayoa - broad-billed sapayoa Family Scotocercidae Genus Scotocerca - streaked scrub warbler Family Sittidae Family Spindalidae Genus Spindalis
Genus Sitta - nuthatches Family Stenostiridae Genus Chelidorhynx - yellow-bellied fantail - (formerly in Rhipidura)
Genus Culicicapa - canary-flycatcher
Genus Elminia
Genus Stenostira – fairy flycatcher Family Sturnidae - starlings
Genus Acridotheres
Genus Agropsar (sometimes included in Sturnus or Sturnia)
Genus Ampeliceps — golden-crested myna
Genus Aplonis— Pacific starlings
Genus Basilornis
Genus Cinnyricinclus — violet-backed starling
Genus Creatophora — wattled starling
Genus Enodes — fiery-browed starling
Genus Gracula — hill myna
Genus Gracupica
Genus Grafisia — white-collared starling
Genus Hartlaubius - Madagascan starling
Genus Hylopsar
Genus Lamprotornis (monophyly requires confirmation)
Genus Leucopsar — Bali myna
Genus Mino
Genus Neocichla — babbling starling
Genus Notopholia - black-bellied starling
Genus Onychognathus
Genus Poeoptera (formerly Pholia, sometimes included in Cinnyricinclus)
Genus Rhabdornis — Philippine creeper (placement here requires confirmation)
Genus Pastor — rosy starling
Genus Sarcops — Coleto
Genus Saroglossa - spot-winged starling
Genus Scissirostrum — grosbeak starling
Genus Speculipastor — magpie starling
Genus Spodiopsar
Genus Spreo
Genus Streptocitta
Genus Sturnia (sometimes included in Sturnus)
Genus Sturnornis — white-faced starling
Genus Sturnus Family Sylviidae - sylviid warblers and allies
Genus Chamaea – wrentit
Genus Chleuasicus – pale-billed parrotbill (Formerly in Paradoxornithidae)
Genus Cholornis (Formerly in Paradoxornithidae)
Genus Chrysomma (Formerly in Timaliidae)
Genus Conostoma – great parrotbill (Formerly in Paradoxornithidae; tentatively placed here)
Genus Fulvetta (Formerly in Alcippe )
Genus Graueria - Grauer's warbler
Genus Horizorhinus – Dohrn's thrush-babbler (Formerly in Timaliidae)
Genus Lioparus – golden-breasted fulvetta (Formerly in Alcippe)
Genus Lioptilus – bush blackcap (Formerly in Timaliidae)
Genus Moupinia - rufous-tailed babbler (Formerly in Chrysomma)
Genus Myzornis - fire-tailed myzornis
Genus Neosuthora – short-tailed parrotbill (Formerly in Paradoxornithidae)
Genus Paradoxornis (Formerly in Paradoxornithidae)
Genus Parophasma - Abyssinian catbird
Genus Pseudoalcippe (Formerly in Illadopsis)
Genus Psittiparus (Formerly in Paradoxornithidae)
Genus Rhopophilus (Formerly in Cisticolidae)
Genus Sinosuthora (Formerly in Paradoxornithidae)
Genus Suthora (Formerly in Paradoxornithidae)
Genus Sylvia – typical warblers Family Teretistridae Genus Teretistris - Cuban warbler Family Thamnophilidae - antbirds
Genus Akletos
Genus Ammonastes - grey-bellied antbird
Genus Ampelornis - grey-headed antbird
Genus Aprositornis - Yapacana antbird
Genus Batara - giant antshrike
Genus Biatas - white-bearded antshrike (Placement here is provisional)
Genus Cercomacra
Genus Cercomacroides
Genus Clytoctantes - bushbirds (Placement here is provisional)
Genus Cymbilaimus - fasciated and bamboo antshrikes
Genus Dichrozona - banded antbird
Genus Drymophila
Genus Dysithamnus - antvireos
Genus Epinecrophylla
Genus Euchrepomis
Genus Formicivora
Genus Frederickena - antshrikes
Genus Gymnocichla - bare-crowned antbird
Genus Gymnopithys
Genus Hafferia
Genus Herpsilochmus
Genus Hylophylax
Genus Hypocnemis - warbling antbirds
Genus Hypocnemoides
Genus Hypoedaleus - spot-backed antshrike
Genus Isleria - antwrens
Genus Mackenziaena - antshrikes
Genus Megastictus - pearly antshrike
Genus Microrhopias - dot-winged antwren
Genus Myrmeciza - white-bellied antbird
Genus Myrmelastes
Genus Myrmoborus
Genus Myrmochanes - black-and-white antbird
Genus Myrmoderus
Genus Myrmophylax - black-throated antbird
Genus Myrmorchilus - stripe-backed antbird
Genus Myrmornis - wing-banded antbird
Genus Myrmotherula - antwrens
Genus Neoctantes - black bushbird
Genus Oneillornis
Genus Percnostola
Genus Phaenostictus - ocellated antbird
Genus Phlegopsis - bare-eyes
Genus Pithys
Genus Poliocrania - chestnut-backed antbird
Genus Pygiptila - spot-winged antshrike
Genus Pyriglena - fire-eyes
Genus Rhegmatorhina
Genus Rhopias - star-throated antwren
Genus Rhopornis - slender antbird (Placement here is provisional)
Genus Sakesphorus - antshrikes
Genus Sciaphylax
Genus Sclateria - silvered antbird
Genus Sipia
Genus Stymphalornis - marsh antwren
Genus Taraba - great antshrike
Genus Terenura
Genus Thamnistes
Genus Thamnomanes
Genus Thamnophilus
Genus Willisornis
Genus Xenornis - speckled antshrike (Placement here is provisional) Family Thraupidae - tanagers and allies
Genus Acanthidops – peg-billed finch
Genus Anisognathus
Genus Bangsia
Genus Buthraupis
Genus Calochaetes – vermilion tanager
Genus Camarhynchus – tree finches
Genus Catamblyrhynchus – plushcap
Genus Catamenia
Genus Certhidea – warbler-finches
Genus Charitospiza – coal-crested finch
Genus Chlorochrysa
Genus Chlorophanes – green honeycreeper
Genus Chlorornis – grass-green tanager
Genus Chrysothlypis
Genus Cissopis – magpie tanager
Genus Cnemathraupis
Genus Cnemoscopus – grey-hooded bush tanager
Genus Coereba – bananaquit (formerly placed in its own family Coerebidae)
Genus Compsospiza – mountain finches
Genus Compsothraupis – scarlet-throated tanager
Genus Conirostrum
Genus Conothraupis
Genus Coryphaspiza – black-masked finch
Genus Coryphospingus
Genus Creurgops
Genus Cyanerpes - honeycreepers
Genus Cyanicterus – blue-backed tanager
Genus Cypsnagra – white-rumped tanager
Genus Dacnis
Genus Diglossa – flowerpiercers
Genus Diuca
Genus Dolospingus – white-naped seedeater
Genus Donacospiza – long-tailed reed finch (may be related to Poospiza)
Genus Dubusia
Genus Emberizoides
Genus Embernagra
Genus Eucometis – grey-headed tanager
Genus Euneornis – orangequit
Genus Geospiza – ground finches
Genus Gubernatrix – yellow cardinal
Genus Haplospiza (paraphyletic with two species of sierra-finch Phrygilus)
Genus Hemispingus
Genus Hemithraupis
Genus Heterospingus
Genus Idiopsar – short-tailed finch
Genus Incaspiza - Inca finches
Genus Iridophanes – golden-collared honeycreeper
Genus Iridosornis
Genus Lanio
Genus Lophospingus
Genus Loxigilla (polyphyletic)
Genus Loxipasser – yellow-shouldered grassquit
Genus Melanodera
Genus Melanospiza – Saint Lucia black finch
Genus Melopyrrha
Genus Nemosia
Genus Neothraupis – shrike-like tanager
Genus Nephelornis – pardusco
Genus Nesospiza
Genus Orchesticus – brown tanager
Genus Oreomanes – giant conebill
Genus Oryzoborus
Genus Parkerthraustes – yellow-shouldered grosbeak (traditionally in Cardinalidae)
Genus Paroaria
Genus Phrygilus – sierra finches
Genus Piezorina – cinereous finch
Genus Pinaroloxias – Cocos finch
Genus Pipraeidea - fawn-breasted tanager
Genus Platyspiza - vegetarian finch
Genus Poospiza – warbling finches
Genus Porphyrospiza - blue finch
Genus Pseudosaltator - rufous-bellied mountain tanager
Genus Pyrrhocoma – chestnut-headed tanager
Genus Ramphocelus
Genus Rhodospingus – crimson-breasted finch
Genus Rowettia – Gough finch
Genus Saltator
Genus Saltatricula – many-colored Chaco finch
Genus Schistochlamys
Genus Sericossypha – white-capped tanager
Genus Sicalis – yellow finches (paraphyletic with Phrygilus)
Genus Sporophila – seedeaters
Genus Stephanophorus – diademed tanager
Genus Tachyphonus
Genus Tangara
Genus Tersina – swallow tanager
Genus Thlypopsis
Genus Thraupis
Genus Tiaris – grassquits (polyphyletic)
Genus Trichothraupis – black-goggled tanager
Genus Urothraupis – black-backed bush tanager
Genus Volatinia – blue-black grassquit
Genus Wetmorethraupis – orange-throated tanager
Genus Xenodacnis – tit-like dacnis
Genus Xenospingus – slender-billed finch Family Tichodromadidae Genus Tichodroma - wallcreeper Family Timaliidae - Old World babblers
Genus Dumetia - tawny-bellied babbler
Genus Macronus – tit-babblers
Genus Pomatorhinus – scimitar babblers
Genus Rhopocichla - dark-fronted babbler
Genus Spelaeornis – wren-babblers
Genus Sphenocichla – wedge-billed babblers
Genus Stachyridopsis
Genus Stachyris
Genus Timalia - chestnut-capped babbler Family Tityridae - tityras and allies
Genus Iodopleura - purpletuft
Genus Laniisoma
Genus Laniocera
Genus Myiobius
Genus Onychorhynchus - royal flycatchers
Genus Oxyruncus - sharpbill
Genus Pachyramphus - becards
Genus Schiffornis
Genus Terenotriccus - ruddy-tailed flycatcher
Genus Tityra
Genus Xenopsaris - white-naped xenopsaris Family Troglodytidae - wrens
Genus Campylorhynchus
Genus Cantorchilus (formerly included in Thryothorus)
Genus Catherpes - canyon wren
Genus Cinnycerthia
Genus Cistothorus
Genus Cyphorhinus
Genus Ferminia - Zapata wren
Genus Henicorhina - wood wrens
Genus Hylorchilus
Genus Microcerculus
Genus Odontorchilus
Genus Pheugopedius (formerly included in Thryothorus)
Genus Salpinctes - rock wren
Genus Thryomanes - Bewick's wren
Genus Thryophilus (formerly included in Thryothorus)
Genus Thryorchilus - timberline wren
Genus Thryothorus - Carolina wren
Genus Troglodytes
Genus Uropsila - white-bellied wren Family Turdidae - thrushes and allies (Monophyly needs confirmation)
Genus Cataponera - Sulawesi thrush
Genus Catharus
Genus Chlamydochaera - fruithunter
Genus Cichlopsis - rufous-brown solitaire
Genus Cochoa
Genus Entomodestes - solitaires
Genus Geokichla
Genus Grandala
Genus Hylocichla - wood thrush
Genus Ixoreus - varied thrush
Genus Myadestes (includes formerly recognized genus Phaeornis)
Genus Neocossyphus - ant thrushes
Genus Platycichla
Genus Psophocichla - groundscraper thrush
Genus Ridgwayia - Aztec thrush
Genus Sialia - bluebirds
Genus Stizorhina - rufous thrush
Genus Turdus - true thrushes
Genus Zoothera - Asian thrush Family Tyrannidae - tyrant flycatchers
Genus Agriornis – shrike-tyrants
Genus Alectrurus
Genus Anairetes
Genus Aphanotriccus
Genus Arundinicola – white-headed marsh tyrant
Genus Atalotriccus – pale-eyed pygmy tyrant
Genus Attila
Genus Calyptura – kinglet calyptura
Genus Camptostoma
Genus Capsiempis – yellow tyrannulet
Genus Casiornis
Genus Cnemarchus – red-rumped bush tyrant
Genus Cnemotriccus – fuscous flycatcher
Genus Cnipodectes - twistwings
Genus Colonia – long-tailed tyrant
Genus Colorhamphus – Patagonian tyrant
Genus Conopias
Genus Contopus – pewees
Genus Corythopis – antpipits
Genus Culicivora – sharp-tailed grass tyrant
Genus Deltarhynchus – flammulated flycatcher
Genus Elaenia
Genus Empidonax
Genus Empidonomus – variegated flycatcher
Genus Euscarthmus
Genus Fluvicola
Genus Griseotyrannus – crowned slaty flycatcher (formerly in Empidonomus)
Genus Gubernetes – streamer-tailed tyrant
Genus Hemitriccus – typical tody-tyrants
Genus Heteroxolmis – black-and-white monjita
Genus Hirundinea – cliff flycatcher
Genus Hymenops – spectacled tyrant
Genus Inezia
Genus Knipolegus – black tyrants
Genus Lathrotriccus
Genus Legatus – piratic flycatcher
Genus Leptopogon
Genus Lessonia - negritos
Genus Lophotriccus
Genus Machetornis – cattle tyrant
Genus Mecocerculus
Genus Megarynchus – boat-billed flycatcher
Genus Mionectes
Genus Mitrephanes
Genus Muscigralla – short-tailed field tyrant
Genus Muscipipra – shear-tailed grey tyrant
Genus Muscisaxicola – ground tyrants
Genus Myiarchus
Genus Myiodynastes
Genus Myiopagis
Genus Myiophobus
Genus Myiornis
Genus Myiotheretes
Genus Myiotriccus – ornate flycatcher
Genus Myiozetetes
Genus Neopipo – cinnamon neopipo
Genus Neoxolmis – chocolate-vented tyrant
Genus Nephelomyias
Genus Nesotriccus – Cocos flycatcher
Genus Ochthoeca
Genus Ochthornis – drab water tyrant
Genus Oncostoma - bentbills
Genus Ornithion
Genus Phaeomyias – mouse-colored tyrannulet
Genus Phelpsia – white-bearded flycatcher
Genus Philohydor – lesser kiskadee
Genus Phyllomyias
Genus Phylloscartes
Genus Piprites
Genus Pitangus – great kiskadee
Genus Platyrinchus – spadebills
Genus Poecilotriccus
Genus Pogonotriccus
Genus Polioxolmis – rufous-webbed bush tyrant
Genus Polystictus
Genus Pseudelaenia – grey-and-white tyrannulet
Genus Pseudocolopteryx
Genus Pseudotriccus
Genus Pyrocephalus
Genus Pyrrhomyias – cinnamon flycatcher
Genus Ramphotrigon
Genus Rhynchocyclus
Genus Rhytipterna
Genus Satrapa – yellow-browed tyrant
Genus Sayornis – phoebes
Genus Serpophaga
Genus Silvicultrix
Genus Sirystes
Genus Stigmatura - wagtail-tyrants
Genus Sublegatus
Genus Suiriri
Genus Tachuris – many-colored rush tyrant
Genus Taeniotriccus – black-chested tyrant
Genus Todirostrum – typical tody-flycatchers
Genus Tolmomyias
Genus Tumbezia – Tumbes tyrant
Genus Tyrannopsis – sulphury flycatcher
Genus Tyrannulus – yellow-crowned tyrannulet
Genus Tyrannus – kingbirds
Genus Uromyias
Genus Xenotriccus
Genus Xolmis
Genus Zimmerius Family Urocynchramidae Genus Urocynchramus - Przewalski's finch Family Vangidae - vangas, helmetshrikes, and allies
Genus Artamella - white-headed vanga
Genus Bias - black-and-white shrike-flycatcher
Genus Calicalicus
Genus Cyanolanius - blue vanga
Genus Euryceros - helmet vanga
Genus Falculea - sickle-billed vanga
Genus Hemipus - flycatcher-shrikes
Genus Hypositta - nuthatch vanga
Genus Leptopterus - chabert vanga
Genus Megabyas - African shrike-flycatcher
Genus Mystacornis - Crossley's vanga
Genus Newtonia
Genus Oriolia - Bernier's vanga
Genus Philentoma
Genus Prionops - helmetshrikes
Genus Pseudobias - Ward's flycatcher
Genus Schetba - rufous vanga
Genus Tephrodornis
Genus Tylas - tylas vanga
Genus Vanga - hook-billed vanga
Genus Xenopirostris Family Viduidae Genus Anomalospiza - cuckoo-finch
Genus Vidua Family Vireonidae - vireos and allies
Genus Cyclarhis - peppershrikes
Genus Erpornis - white-bellied erpornis
Genus Hylophilus
Genus Pteruthius - shrike-babblers
Genus Vireo - vireos
Genus Vireolanius Family Zeledoniidae Genus Zeledonia Family Zosteropidae - white-eyes
Genus Apalopteron – Bonin white-eye
Genus Cleptornis – golden white-eye
Genus Dasycrotapha
Genus Heleia
Genus Lophozosterops
Genus Megazosterops – giant white-eye
Genus Oculocincta – pygmy white-eye
Genus Rukia
Genus Sterrhoptilus
Genus Tephrozosterops – rufescent darkeye
Genus Woodfordia
Genus Yuhina
Genus Zosterops - Mountain blackeye
Genus Zosterornis Family Uncertain (This has traditionally been considered a member of the family Pachycephalidae, but recent genetic evidence suggests it should be placed in a monotypic subfamily of the family Bombycillidae, or even its own family, Hylocitreidae)
Genus Hylocitrea
Pelecaniformes
Pelicans, ibises, shoebills, egrets, herons, etc. Family Ardeidae - herons, egrets, and bitterns
Genus Agamia – agami heron
Genus Ardea
Genus Ardeola – pond herons
Genus Botaurus
Genus Bubulcus – cattle egret (sometimes included in Ardea)
Genus Butorides – green-backed herons (sometimes included in Ardea)
Genus Cochlearius – boat-billed heron
Genus Egretta
Genus Gorsachius
Genus Ixobrychus
Genus Nyctanassa – American night herons
Genus Nycticorax (sometimes includes Nyctanassa)
Genus Pilherodius – capped heron
Genus Syrigma – whistling heron
Genus Tigriornis – white-crested tiger heron
Genus Tigrisoma
Genus Zebrilus – zigzag heron
Genus Zonerodius – forest bittern Family Balaenicipitidae Genus Balaeniceps - shoebill Family Pelecanidae Genus Pelecanus - pelicans Family Scopidae Genus Scopus - hamerkop (sometimes included in Balaenicipitidae) Family Threskiornithidae - ibises and spoonbills
Genus Bostrychia
Genus Cercibis - sharp-tailed ibis
Genus Eudocimus
Genus Geronticus
Genus Lophotibis - Madagascan ibis
Genus Mesembrinibis - green ibis
Genus Nipponia - crested ibis
Genus Phimosus - bare-faced ibis
Genus Platalea - spoonbills
Genus Plegadis
Genus Pseudibis
Genus Thaumatibis - giant ibis
Genus Theristicus
Genus Threskiornis
Phaethontiformes
Family Phaethontidae Genus Phaethon - tropicbirds
Phoenicopteriformes Family Phoenicopteridae - flamingos
Genus Phoeniconaias - lesser flamingo
Genus Phoenicoparrus
Genus Phoenicopterus
Piciformes
Woodpickers, flickers, toucans, aracaris, motmots, etc. Family Bucconidae – puffbirds, nunbirds, and nunlets
Genus Bucco
Genus Chelidoptera - swallow-winged puffbird
Genus Hapaloptila - white-faced nunbird
Genus Hypnelus
Genus Malacoptila
Genus Micromonacha - lanceolated monklet
Genus Monasa
Genus Nonnula
Genus Notharchus
Genus Nystalus Family Capitonidae – American barbets
Genus Capito
Genus Eubucco Family Galbulidae – jacamars
Genus Brachygalba
Genus Galbalcyrhynchus
Genus Galbula
Genus Jacamaralcyon - three-toed jacamar
Genus Jacamerops - great jacamar Family Indicatoridae – honeyguides
Genus Indicator
Genus Melichneutes - lyre-tailed honeyguide
Genus Melignomon
Genus Prodotiscus - honeybirds Family Lybiidae – African barbets (recently split from Capitonidae)
Genus Buccanodon - yellow-spotted barbet
Genus Gymnobucco
Genus Lybius
Genus Pogoniulus - tinkerbirds
Genus Stactolaema
Genus Trachyphonus
Genus Tricholaema Family Megalaimidae – Asian barbets (recently split from Capitonidae)
Genus Caloramphus
Genus Psilopogon Family Picidae – woodpeckers, piculets, and wrynecks
Genus Blythipicus
Genus Campephilus
Genus Campethera
Genus Celeus
Genus Chloropicus
Genus Chrysocolaptes – flamebacks
Genus Chrysophlegma
Genus Colaptes – flickers
Genus Dendrocopos
Genus Dendrocoptes
Genus Dendropicos
Genus Dinopium – flamebacks
Genus Dryobates
Genus Dryocopus
Genus Gecinulus (placement in Megapicini tentative)
Genus Geocolaptes – ground woodpeckers
Genus Hemicircus
Genus Jynx - wrynecks
Genus Leiopicus – yellow-crowned woodpecker
Genus Leuconotopicus
Genus Meiglyptes
Genus Melanerpes
Genus Micropternus – rufous woodpecker (formerly in Celeus)
Genus Mulleripicus
Genus Nesoctites – Antillean piculet
Genus Picoides
Genus Piculus
Genus Picumnus – American piculets
Genus Picus
Genus Reinwardtipicus - Orange-backed woodpecker
Genus Sasia – Asian piculets
Genus Sphyrapicus – sapsuckers
Genus Veniliornis
Genus Xiphidiopicus – Cuban green woodpecker (Placement in Dendropicini tentative)
Genus Yungipicus Family Ramphastidae – toucans
Genus Andigena - mountain toucans
Genus Aulacorhynchus - green toucanet
Genus Pteroglossus - aracaris
Genus Ramphastos
Genus Selenidera Family Semnornithidae – toucan-barbets (recently split from Capitonidae)
Genus Semnornis
Podicipediformes Family Podicipedidae - grebes
Genus Aechmophorus
Genus Podicephorus - great grebe
Genus Podiceps
Genus Podilymbus
Genus Poliocephalus
Genus Rollandia
Genus Tachybaptus
Procellariiformes
Petrels, storm petrels, albatrosses, and diving petrels Family Diomedeidae - albatrosses
Genus Diomedea - great albatrosses
Genus Phoebastria - North Pacific albatrosses
Genus Phoebetria
Genus Thalassarche - "mollymawks" Family Hydrobatidae - northern storm petrels
Genus Hydrobates - European storm petrel
Genus Oceanodroma Family Oceanitidae - southern storm petrels
Genus Fregetta
Genus Garrodia - grey-backed storm petrel
Genus Nesofregetta - Polynesian storm petrel
Genus Oceanites
Genus Pelagodroma - white-faced storm petrel Family Procellariidae Genus Aphrodroma - Kerguelen petrel
Genus Ardenna
Genus Bulweria
Genus Calonectris
Genus Daption - Cape petrel
Genus Fulmarus - fulmars
Genus Halobaena - blue petrel
Genus Macronectes - giant petrels
Genus Pachyptila
Genus Pagodroma - snow petrel
Genus Pelecanoides - diving petrels
Genus Procellaria
Genus Pseudobulweria
Genus Pterodroma - gadfly petrels
Genus Puffinus
Genus Thalassoica - Antarctic petrel
Psittaciformes
Parrots, parakeets, macaws, and cockatoos Family Cacatuidae - cockatoos
Genus Cacatua
Genus Callocephalon - gang-gang cockatoo
Genus Calyptorhynchus
Genus Eolophus - galah
Genus Lophochroa - Major Mitchell's cockatoo
Genus Nymphicus - cockatiel
Genus Probosciger - palm cockatoo Family Nestoridae - New Zealand parrots
Genus Nestor Family Psittacidae - New World and African parrots
Genus Alipiopsitta - yellow-faced parrot
Genus Amazona - "Amazons"
Genus Anodorhynchus
Genus Ara
Genus Aratinga
Genus Bolborhynchus
Genus Brotogeris
Genus Conuropsis - Carolina parakeet
Genus Coracopsis - Vasa parrot
Genus Cyanoliseus - burrowing parrot
Genus Cyanopsitta - Spix's macaw
Genus Deroptyus – red-fan parrot
Genus Diopsittaca - red-shouldered macaw
Genus Enicognathus
Genus Eupsittula
Genus Forpus
Genus Graydidascalus - short-tailed parrot
Genus Guaruba - golden parakeet
Genus Hapalopsittaca
Genus Leptosittaca - golden-plumed parakeet
Genus Myiopsitta
Genus Nannopsittaca
Genus Ognorhynchus - yellow-eared parrot
Genus Orthopsittaca - red-bellied macaw
Genus Pionites – caiques
Genus Pionopsitta - pileated parrot
Genus Pionus
Genus Poicephalus
Genus Primolius
Genus Psilopsiagon
Genus Psittacara
Genus Psittacus – grey parrot and Timneh parrot
Genus Pyrilia
Genus Pyrrhura
Genus Rhynchopsitta
Genus Thectocercus - blue-crowned parakeet
Genus Touit
Genus Triclaria - blue-bellied parrot Family Psittaculidae - Old World parrots
Genus Agapornis - lovebirds
Genus Alisterus
Genus Aprosmictus
Genus Barnardius - Australian ringneck (sometimes included in Platycercus)
Genus Bolbopsittacus - guaiabero
Genus Chalcopsitta
Genus Charmosyna
Genus Cyanoramphus
Genus Cyclopsitta
Genus Eclectus
Genus Eos
Genus Eunymphicus
Genus Geoffroyus
Genus Glossopsitta - musk lorikeet
Genus Lathamus - swift parrot
Genus Loriculus - hanging parrot
Genus Lorius
Genus Melopsittacus - budgerigar
Genus Micropsitta - pygmy parrot
Genus Neophema
Genus Neopsephotus - Bourke's parrot (sometimes included in Neophema)
Genus Neopsittacus
Genus Northiella - bluebonnet (often included in Psephotus)
Genus Oreopsittacus - plum-faced lorikeet
Genus Parvipsitta
Genus Pezoporus
Genus Phigys - collared lory
Genus Platycercus - rosellas
Genus Polytelis
Genus Prioniturus - racket-tails
Genus Prosopeia - shining parrot
Genus Psephotellus
Genus Psephotus - red-rumped parrot
Genus Pseudeos
Genus Psittacella - tiger parrot
Genus Psittacula
Genus Psittaculirostris
Genus Psitteuteles (sometimes classified in the Trichoglossus)
Genus Psittinus
Genus Purpureicephalus - red-capped parrot
Genus Tanygnathus
Genus Trichoglossus
Genus Vini Family Psittrichasiidae Genus Coracopsis - Vasa parrot
Genus Psittrichas - Pesquet's parrot Family Strigopidae Genus Strigops - kākāpō
Pterocliformes Family Pteroclidae - sandgrouse
Genus Calopterocles
Genus Nyctiperdix
Genus Pterocles
Genus Syrrhaptes
Rheiformes Family Rheidae Genus Rhea
Sphenisciformes Family Spheniscidae - penguins
Genus Aptenodytes
Genus Eudyptes - crested penguins
Genus Eudyptula
Genus Megadyptes
Genus Pygoscelis
Genus Spheniscus - banded penguins
Strigiformes
Owls Family Strigidae - true owls
Genus Aegolius – saw-whet owls
Genus Asio – eared owls
Genus Athene
Genus Bubo – horned owls (paraphyletic with Nyctea, Ketupa, and Scotopelia)
Genus Ciccaba
Genus Glaucidium – pygmy owls
Genus Jubula – maned owl
Genus Lophostrix – crested owl
Genus Margarobyas – bare-legged owl
Genus Megascops – screech owls
Genus Micrathene – elf owl
Genus Nesasio – fearful owl
Genus Ninox – Asian and Australasian hawk-owls and boobooks
Genus Otus – scops owls (probably paraphyletic)
Genus Pseudoscops – Jamaican owl
Genus Psiloscops – flammulated owl
Genus Ptilopsis – white-faced owl
Genus Pulsatrix – spectacled owl
Genus Pyrroglaux – Palau owl
Genus Scotopelia - fishing owls
Genus Strix – earless owls
Genus Surnia – northern hawk-owl
Genus Uroglaux – Papuan hawk-owl
Genus Xenoglaux – long-whiskered owlet Family Tytonidae - barn owls
Genus Phodilus - bay owls
Genus Tyto
StruthioniformesFamily Struthionidae - ostriches
Genus Struthio
Suliformes
Boobies, gannets, frigatebirds, cormorants, shags, and darters Family Anhingidae Genus Anhinga - darters and anhinga Family Fregatidae Genus Fregata - frigatebirds Family Phalacrocoracidae Genus Phalacrocorax - cormorants and shags Family Sulidae Genus Morus - gannets
Genus Papasula - Abbott's booby
Genus Sula - boobies
Tinamiformes Family Tinamidae - tinamous
Genus Crypturellus
Genus Eudromia
Genus Nothocercus
Genus Nothoprocta
Genus Nothura
Genus Rhynchotus
Genus Taoniscus - dwarf tinamou
Genus Tinamotis
Genus Tinamus
Trogoniformes
Trogons and quetzals Family Trogonidae'
Genus Apalharpactes Genus Apaloderma Genus Euptilotis - eared quetzal
Genus Harpactes Genus Pharomachrus Genus Priotelus Genus Trogon''
Birds
Birds
Bird Genera | List of bird genera | [
"Biology"
] | 22,217 | [
"Lists of biota",
"Lists of animals",
"Animals"
] |
12,115,017 | https://en.wikipedia.org/wiki/Silicon%20tetrachloride%20%28data%20page%29 | This page provides supplementary chemical data on silicon tetrachloride.
Material Safety Data Sheet
The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source, it this case, noting that one should "avoid all contact! In all cases consult a doctor! ... inhalation causes sore throat and Burning sensation".
Structure and properties
Thermodynamic properties
Spectral data
References
NIST Standard Reference Database
David R. Lide, ed. Handbook of Chemistry and Physics, 85th Edition, Internet Version 2005. CRC Press, 2005.
Chemical data pages
Chemical data pages cleanup | Silicon tetrachloride (data page) | [
"Chemistry"
] | 143 | [
"Chemical data pages",
"nan"
] |
12,115,249 | https://en.wikipedia.org/wiki/Avco-Lycoming%20AGT1500 | The Avco-Lycoming AGT1500 is a gas turbine engine. It is the main powerplant of the M1 Abrams series of tanks. The engine was originally designed and produced by the Lycoming Turbine Engine Division in the Stratford Army Engine Plant. In 1995, production was moved to the Anniston Army Depot in Anniston, Alabama, after the Stratford Army Engine Plant was shut down.
Specifications
Engine output peaks at , with of torque at that peak, which occurs at 3,000 rpm. The turbine can provide torque in excess of at significantly lower RPMs. The engine weighs approximately and occupies a volume of , measuring .
The engine can use a variety of fuels, including jet fuel, gasoline, diesel and marine diesel.
The engine is a three-shaft machine composed of five sub-modules:
Recuperator – a fixed cylindrical regenerative heat exchanger that extracts waste heat from the exhaust gases and uses it to preheat the compressed air
Rotating Gas Producer – the five-stage, dual-spool compressor which achieves a 14.5:1 compression ratio at full power, driven by the compressor turbine, which operates with a maximum turbine inlet temperature of
Accessory Gearbox – bevel gears that extract from the high-pressure spool to operate the fuel control unit, starter, oil pump, and vehicle hydraulic pump
Power Turbines – the first stage of the two-stage power turbine is driven by a variable-geometry nozzle to improve efficiency
Reduction Gearbox – reduces power turboshaft speed
History
Development had started by 1964 with a contract given to Chrysler in 1976, originally as an engine for the later cancelled MBT-70.
In the early 1970s, the AGT1500 was developed into the PLT27, a flight-weight turboshaft for use in helicopters. This engine lost to the General Electric GE12 (T700) in three separate competitions to power the UH-60, AH-64, and SH-60. Serial production of the AGT1500 began in 1980; by 1992, more than 11,000 engines had been delivered. In 1986, with the Cold War about to wind down, Textron Lycoming began developing a commercial marine derivative, which they called the TF15.
See also
Anselm Franz, lead designer of AGT1500 at the early stage
References
External links
AGT1500 Gas Turbine Engine
AGT1500 Turbine Technology pdf on Honeywell.com
Gas turbines
Tank engines
Honeywell Aerospace aircraft engines | Avco-Lycoming AGT1500 | [
"Technology"
] | 503 | [
"Engines",
"Gas turbines"
] |
12,115,370 | https://en.wikipedia.org/wiki/Comparison%20of%20e-book%20formats | The following is a comparison of e-book formats used to create and publish e-books.
The EPUB format is the most widely supported e-book format, supported by most e-book readers except Amazon Kindle devices. Most e-book readers also support the PDF and plain text formats. E-book software can be used to convert e-books from one format to another, as well as to create, edit and publish e-books.
Format descriptions
Formats available include, but are not limited to:
Broadband eBooks (BBeB)
The digital book format originally used by Sony Corporation. It is a proprietary format, but some reader software for general-purpose computers, particularly under Linux (for example, Calibre's internal viewer), have the capability to read it. The LRX file extension represents a DRM-encrypted e-book. More recently, Sony has converted its books from BBeB to EPUB and is now issuing new titles in EPUB.
Comic Book Archive file
Compiled HTML
CHM format is a proprietary format based on HTML. Multiple pages and embedded graphics are distributed along with metadata as a single compressed file. The indexing is both for keywords and for full text search.
DAISY – ANSI/NISO Z39.86
The Digital Accessible Information SYstem (DAISY) is an XML-based open standard published by the National Information Standards Organization (NISO) and maintained by the DAISY Consortium for people with print disabilities. DAISY has wide international support with features for multimedia, navigation and synchronization. A subset of the DAISY format has been adopted by law in the United States as the National Instructional Material Accessibility Standard (NIMAS), and K-12 textbooks and instructional materials are now required to be provided to students with disabilities.
DAISY is already aligned with the EPUB technical standard, and is expected to fully converge with its forthcoming EPUB3 revision.
Djvu
DjVu is a format specialized for storing scanned documents. It includes advanced compressors optimized for low-color images, such as text documents. Individual files may contain one or more pages. DjVu files cannot be re-flowed.
The contained page images are divided in separate layers (such as multi-color, low-resolution, background layer using lossy compression, and few-colors, high-resolution, tightly compressed foreground layer), each compressed in the best available method. The format is designed to decompress very quickly, even faster than vector-based formats.
The advantage of DjVu is that it is possible to take a high-resolution scan (300–400 DPI), good enough for both on-screen reading and printing, and store it very efficiently. Provided the images are reasonably clean and the most aggressive compression settings are used, a couple hundred 600-DPI black-and-white text scans can be stored in less than a megabyte.
DOC
DOC is a document file format that is directly supported by few e-book readers. Its advantages as an e-book format is that it can be easily converted to other e-book formats and it can be reflowed. It can be easily edited using Microsoft software, and any of several other programs. Note that the format has changed several times since its original release, and there are numerous incompatibility difficulties between various releases and the assorted programs which attempt to read / write the format.
DOCX
DOCX is a document file format that is directly supported by few e-book readers. Its advantages as an e-book format are that it can be easily converted to other e-book formats and it can be reflowed. It can be easily edited.
EPUB
The EPUB (formerly OEBPS) format is a technical standard for e-books created by the International Digital Publishing Forum (IDPF).
The format has gained some popularity as a vendor-independent XML-based e-book format. The format can be read by the Kobo eReader, BlackBerry devices, Apple's Apple Books app running on Macintosh computers and iOS devices, Google Play Books app running on Android and iOS devices, Barnes & Noble Nook, Amazon Kindle Fire, Sony Reader, BeBook, Bookeen Cybook Gen3 (with firmware v2 and up), Adobe Digital Editions, Lexcycle Stanza, FBReader, PocketBook eReader, Aldiko, the Mozilla Firefox add-on EPUBReader, Lucifox, Okular and other reading apps.
Adobe Digital Editions uses .epub format for its e-books, with digital rights management (DRM) protection provided through their proprietary ADEPT mechanism. The ADEPT framework and scripts have been reverse-engineered to circumvent this DRM system.
eReader
eReader is a freeware program for viewing Palm Digital Media electronic books which use the pdb format used by many Palm applications. Versions are available for Android, BlackBerry, iOS, Palm OS (not webOS), Symbian, Windows Mobile Pocket PC/Smartphone, and macOS. The reader shows text one page at a time, as paper books do. eReader supports embedded hyperlinks and images. Additionally, the Stanza application for the iPhone and iPod Touch can read both encrypted and unencrypted eReader files.
The program supports features like bookmarks and footnotes, enabling the user to mark any page with a bookmark and any part of the text with a footnote-like commentary. Footnotes can later be exported as a Memo document.
On July 20, 2009, Barnes & Noble made an announcement implying that eReader would be the company's preferred format to deliver e-books. Exactly three months later, in a press release by Adobe, it was revealed Barnes & Noble would be joining forces with the software company to standardize the EPUB and PDF e-book formats. Barnes & Noble e-books are now sold mostly in EPUB format.
FictionBook (fb2)
FictionBook is an XML-based e-book format, supported by free readers such as PocketBook eReader, FBReader, Okular, CoolReader, BeBook and STDU Viewer.
The FictionBook format does not specify the appearance of a document; instead, it describes its structure and semantics. All e-book metadata, such as the author name, title, and publisher, is also present in the file. Hence the format is convenient for automatic processing, indexing, and e-book collection management. This is also convenient for book storage for later automatic conversion into other formats.
Founder Electronics
APABI is a format devised by Founder Electronics. It is a popular format for Chinese e-books. It can be read using the Apabi Reader software, and produced using Apabi Publisher. Both .xeb and .ceb files are encoded binary files. The ILiad e-book device includes an Apabi viewer.
Hypertext Markup Language
HTML is the markup language used for most web pages. E-books using HTML can be read using a Web browser. The specifications for the format are available without charge from the W3C.
HTML adds specially marked meta-elements to otherwise plain text encoded using character sets like ASCII or UTF-8. As such, suitably formatted files can be, and sometimes are, generated by hand using a plain text editor or programmer's editor. Many HTML generator applications exist to ease this process and often require less intricate knowledge of the format details involved.
HTML on its own is not a particularly efficient format to store information in, requiring more storage space for a given work than many other formats. However, several e-Book formats including the Amazon Kindle, Open eBook, Compiled HTML, Mobipocket and EPUB store each book chapter in HTML format, then use ZIP compression to compress the HTML data, images, metadata and style sheets into a single, significantly smaller, file.
HTML files encompass a wide range of standards and displaying HTML files correctly can be complicated. Additionally many of the features supported, such as forms, are not relevant to e-books.
iBook (Apple)
The .ibooks format is created with the free iBooks Author e-book layout software from Apple Inc. This proprietary format is based on the EPUB standard, with some differences in the CSS tags used in an ibooks format file, this making it incompatible with the EPUB specification. The End-User Licensing Agreement (EULA) included with iBooks Author states that "If you want to charge a fee for a work that includes files in the .ibooks format generated using iBooks Author, you may only sell or distribute such work through Apple". The "through Apple" will typically be in the Apple Apple Books store. The EULA further states that "This restriction does not apply to the content of such works when distributed in a form that does not include files in the .ibooks format." Therefore, Apple has not included distribution restrictions in the iBooks Author EULA for ibooks format e-books created in iBooks Author that are made available for free, and it does not prevent authors from re-purposing the content in other e-book formats to be sold outside the iBookstore. This software currently supports import and export functionally for three formats. ibook, Plain text and PDF. Versions 2.3 and later of iBooks Author support importing EPUB and exporting EPUB 3.0.
IEC 62448
IEC 62448 is an international standard created by International Electrotechnical Commission (IEC), Technical Committee 100, Technical Area 10 (Multimedia e-publishing and e-book).
The current version of IEC 62448 is an umbrella standard that contains as appendices two concrete formats, XMDF of Sharp and BBeB of Sony. However, BBeB has been discontinued by Sony and the version of XMDF that is in the specification is out of date. The IEC TA10 group is discussing the next steps, and has invited the IDPF organization which has standardized EPUB to be a liaison. It is possible that the current version of EPUB or the EPUB3 revision may be added to IEC 62448. Meanwhile, a number of Japanese companies have proposed that IEC standardize a proposed new Japanese-centric file format that is expected to unify DotBook of Voyager Japan and XMDF of Sharp. This new format has not been publicly disclosed as of November 2010 but it is supposed to cover basic representations for the Japanese language. Technically speaking, the revision is supposed to provide a Japanese minimum set, a Japanese extension set, and a stylesheet language. These issues were discussed in the TC100 meeting held in October 2010 but no decisions were taken besides offering the liaison status to IDPF.
INF (IBM)
IBM created this e-book format and used it extensively for OS/2 and other of its operating systems. The INF files were often digital versions of printed books that came with some bundles of OS/2 and other products. There were many other newsletters and monthly publications (e.g.: EDM/2) available in the INF format too.
The advantage of INF is that it is very compact and very fast. It also supports images, reflowed text, tables and various list formats. INF files get generated by compiling the markup text files — in the Information Presentation Facility (IPF) format — into binary files.
Originally only IBM created an INF viewer and compiler, but later open source viewers like NewView, DocView and others appeared. There is also an open source IPF compiler named WIPFC, created by the Open Watcom project.
Kindle (Amazon)
With the release of the Kindle Fire reader in late 2011, Amazon.com also released Kindle Format 8, also known as .AZW3. The .azw3 file format supports a subset of HTML5 and CSS3 features, with some additional nonstandard features; the new data is stored within a container which can also be used to store a Mobi content document, allowing limited backwards compatibility.
Older Kindle e-readers use the proprietary format, AZW. It is based on the Mobipocket standard, with a slightly different serial number scheme (it uses an asterisk instead of a dollar sign) and its own DRM formatting. It also lacks some Mobipocket features such as JavaScript. .prc publications can be read directly on the Kindle.
Because e-books bought on the Kindle are delivered over its wireless system called Whispernet, the user does not see the AZW files during the download process. The Kindle format is available on a variety of platforms, such as through the Kindle app for the various mobile device platforms.
Microsoft LIT
DRM-protected LIT files are only readable in the proprietary Microsoft Reader program, as the .LIT format, otherwise similar to Microsoft's CHM format, includes DRM features. Other third-party readers, such as Lexcycle Stanza, can read unprotected LIT files.
The Microsoft Reader uses patented ClearType display technology. In Reader navigation works with a keyboard, mouse, stylus, or through electronic bookmarks. The Catalog Library records reader books in a personalized home page, and books are displayed with ClearType to improve readability. A user can add annotations and notes to any page, create large-print e-books with a single command, or create free-form drawings on the reader pages. A built-in dictionary allows the user to look up words.
In August 2011, Microsoft announced they were discontinuing both Microsoft Reader and the use of the .lit format for e-books at the end of August 2012, and ending sales of the format on November 8, 2011.
Mobipocket
The Mobipocket e-book format is based on the Open eBook standard using XHTML and can include JavaScript and frames. It also supports native SQL queries to be used with embedded databases. There is a corresponding e-book reader.
The Mobipocket Reader has a home page library. Readers can add blank pages in any part of a book and add free-hand drawings. Annotations – highlights, bookmarks, corrections, notes, and drawings – can be applied, organized, and recalled from a single location. Images are converted to GIF format and have a maximum size of 64K, sufficient for mobile phones with small screens, but rather restrictive for newer gadgets. Mobipocket Reader has electronic bookmarks, and a built-in dictionary.
The reader has a full screen mode for reading and support for many PDAs, communicators, and smartphones. Mobipocket products support most Windows, Symbian, BlackBerry and Palm operating systems, but not the Android platform. Using WINE, the reader works under Linux or Mac OS X. Third-party applications like Okular, Calibre, and FBReader can also be used under Linux or Mac OS X, but they work only with unencrypted files.
The Amazon Kindle can read unprotected .mobi files, as can Amazon's Kindle application for Windows and MacOS. Amazon has also developed an .epub to .mobi converter called KindleGen, and it supports IDPF 1.0 and IDPF 2.0 EPUB format.
Multimedia e-books
A multimedia e-book is media and book content that utilizes a combination of different book content formats. The term can be used as a noun (a medium with multiple content formats) or as an adjective describing a medium as having multiple content formats.
The term multimedia e-book is used in contrast to media which only utilize traditional forms of printed or text books. Multimedia e-books include a combination of text, audio, images, video, or interactive content formats. Much like how a traditional book can contain images to help the text tell a story, a multimedia e-book can contain other elements not formerly possible to help tell the story.
With the advent of more widespread tablet-like computers, such as the smartphone, some publishing houses are planning to make multimedia ebooks, such as Penguin.
Newton Digital Book
Commonly known as a Newton Book, but officially referred to as a Newton Digital Book; a single Newton package file can contain multiple books (for example, the three books of a trilogy might be packaged together). Newton Books are created using Newton Press, or, for more advanced content, Newton Book Maker and Newton Toolkit.
All systems running the Newton operating system (the most common include the Newton MessagePads, eMates, Siemens Secretary Stations, Motorola Marcos, Digital Ocean Seahorses and Tarpons) have built-in support for viewing Newton books, through a system service known as Newton Book Reader. The Newton package format was released to the public by Newton, Inc. prior to that company's absorption into Apple Computer. The format is thus arguably open and various people have written readers for it (writing a Newton book converter has even been assigned as a university-level class project).
Newton books have no support for DRM or encryption. They do support internal links, potentially multiple tables of contents and indexes, embedded gray scale images, and even some scripting capability using NewtonScript (for example, it's possible to make a book in which the reader can influence the outcome). Newton books utilize Unicode and are thus available in numerous languages. An individual Newton Book may actually contain multiple views representing the same content in different ways (such as for different screen resolutions).
Open Packaging Format
OPF is an XML-based e-book format created by E-Book Systems; it has been superseded by the EPUB electronic publication standard.
Portable Document Format
Invented by Adobe Systems, and first released in 1993, PDF became ISO 32000 in 2008. The format was developed to provide a platform-independent means of exchanging fixed-layout documents. Derived from PostScript, but without language features like loops, PDF adds support for features such as compression, passwords, semantic structures and DRM. Because PDF documents can easily be viewed and printed by users on a variety of computer platforms, they are very common on the Internet and in document management systems worldwide. The current PDF specification, ISO 32000-1:2008, is available from ISO's website, and under special arrangement, without charge from Adobe.
Because the format is designed to reproduce fixed-layout pages, re-flowing text to fit mobile device and e-book reader screens has traditionally been problematic. This limitation was addressed in 2001 with the release of PDF Reference 1.5 and Tagged PDF, but third-party support for this feature was limited until the release of PDF/UA in 2012.
Many products support creating and reading PDF files, such as Adobe Acrobat, PDFCreator and LibreOffice, and several programming libraries such as iText and FOP. Third-party viewers such as xpdf and Nitro PDF are also available. Mac OS X has built-in PDF support, both for creation as part of the printing system and for display using the built-in Preview application.
Older PDF files are supported by almost all modern e-book readers, tablets and smartphones. Newer PDF files may not display properly on older e-readers, may not open, or may crash them. However, PDF reflow based on Tagged PDF, as opposed to re-flow based on the actual sequence of objects in the content-stream, is not yet commonly supported on mobile devices. Such Re-flow options as may exist are usually found under "view" options, and may be called "word-wrap".
Plain text
The first e-books were in plain text (.txt) format, supplied for free by the Project Gutenberg community, but the format itself existed before e-books. The plain text format doesn't support DRM or formatting options (such as different fonts, graphics or colors). It has excellent portability as it is the simplest e-book encoding possible; a plain text file contains only ASCII or Unicode text (text files with UTF-8 or UTF-16 encoding are also popular for languages other than English). Almost all operating systems can read ASCII text files (e.g. Unix, Macintosh, Microsoft Windows, DOS and other systems) and newer operating systems support Unicode text files as well. The only potential for portability problems of ASCII text files is that operating systems differ in their preferred line-ending convention and their interpretation of values outside the ASCII range (their character encoding). Conversion of files from one to another line-ending convention is easy with free software. DOS and Windows use CRLF, Unix and Apple's OS X use LF, and Mac OS up to and including OS 9 uses CR. By convention, lines are often broken to fit into 80 characters, a legacy of older terminals and consoles. Alternately, each paragraph may be a single line.
When Unicode is not in use, the size in bytes of a text file is simply the number of characters, including spaces, and with a new line counting for 1 or 2. For example, the Bible, which is approximately 800,000 words, is about 4 MB.
Plucker
Plucker is a free and open-source mobile and desktop e-book reader application with its own associated file format and software to automatically generate Plucker files from text, PDF, HTML, or other document format files, web sites or RSS feeds. The format is public and well-documented. Free readers are available for all kinds of desktop computers and many PDAs.
PostScript
PostScript is a page description language used in the electronic and desktop publishing areas for defining the contents and layout of a printed page, which can be used by a rendering program to assemble and create the actual output bitmap. Many office printers directly support interpreting PostScript and printing the result. As a result, the format also sees wide use in the Unix world.
RTF
Rich Text Format is a document file format that is supported by many e-book readers. Its advantages as an e-book format are that it is widely supported, and it can be reflowed. It can be easily edited. It can be easily converted to other e-book formats, increasing its support.
SSReader
The digital book format used by the digital library company Chaoxing Digital Library () in China. It is a proprietary raster image compression and binding format, with reading time OCR plug-in modules. The company scanned a large number of Chinese books from the National Library of China, which became the major stock of their service. The detailed format is not published. There are also other commercial e-book formats used in Chinese digital libraries.
Text Encoding Initiative
TEI Lite is the most popular of the TEI-based (and thus XML-based or SGML-based) electronic text formats.
TomeRaider
The TomeRaider e-book format is a proprietary format. There are versions of the format for Windows, Windows Mobile (aka Pocket PC), Palm, Symbian and iPhone. Capabilities of the TomeRaider3 e-book reader vary considerably per platform: the Windows and Windows Mobile editions support full HTML and CSS. The Palm edition supports limited HTML (e.g., no tables or fonts), and CSS support is missing. For Symbian there is only the older TomeRaider2 format, which does not render images or offer category search facilities. Despite these differences any TomeRaider e-book can be browsed on all supported platforms. The TomeRaider website claims to have over 4000 e-books available, including free versions of the Internet Movie Database and Wikipedia.
Open XML Paper Specification
Open XML Paper Specification (also referred to as OpenXPS) is an open specification for a page description language and a fixed-document format. Microsoft developed it as the XML Paper Specification (XPS). In June 2009, Ecma International adopted it as international standard ECMA-388.
The format is intentionally restricted to sequences of glyphs (fixed runs of text), paths (geometry that can be filled, or stroked, by a brush), and brushes (descriptions of shaped brushes used to render paths).
This reduces the possibility of inadvertent introduction of malicious content and simplifies the implementation of compatible renderers.
Comparison
Features
Supporting platforms
See also
Comparison of e-readers
Comparison of Android e-reader software – includes software e-book readers for Android devices
Comparison of iOS e-reader software – includes software e-book readers for iOS devices
Notes and references
Notes
References
Further reading
Cope, B., & Mason, D. (2002). Markets for electronic book products. C-2-C series, bk. 3.2. Altona, Vic: Common Ground Pub.
Hanttula, D. (2001). Pocket PC Handbook.
External links
Ebook reader articles at Mobile Read Wiki
Daisy 3: A Standard for Accessible Multimedia Books (archive link)
An E-Book Buyer's Guide to Privacy
e-book formats
Electronic documents
Electronic publishing | Comparison of e-book formats | [
"Technology"
] | 5,173 | [
"Computing comparisons"
] |
12,115,584 | https://en.wikipedia.org/wiki/Dip%20soldering | Dip soldering is a small-scale soldering process by which electronic components are soldered to a printed circuit board (PCB) to form an electronic assembly. The solder wets to the exposed metallic areas of the board (those not protected with solder mask), creating a mechanical and electrical connection.
Dip soldering is used for both through-hole printed circuit assemblies, and surface mount. It is one of the cheapest methods to solder and is extensively used in the small scale industries of developing countries .
Dip soldering is a manual equivalent of automated wave soldering. The apparatus required is just a small tank containing molten solder. A PCB with mounted components is dipped manually into the tank so that the molten solder sticks to the exposed metallic areas of the board.
Dip solder process
Dip soldering is accomplished by submerging parts to be joined into a molten solder bath. Thus, all components surfaces are coated with filler metal. Solders have low surface tension and high wetting capability. There are many types of solders, each used for different applications:
Lead–silver is used for strength at higher-than-room temperature.
Tin–lead is used as a general-purpose solder
Tin–zinc is used for aluminium
Cadmium–silver is used for strength at high temperatures
Zinc–aluminium is used for aluminium and corrosion resistance
Tin–silver and tin–bismuth are used for electronics.
The molten bath can be any suitable filler metal, but the selection is usually confined to the lower melting point elements. The most common dip soldering operations use zinc-aluminum and tin-lead solders.
Solder pot metal: cast iron or steel, electrically heated.
Bath temperature: (for binary tin-lead alloys) or (for lead-free alloys)
Solder composition: 60% , 40% or eutectic alloy.
Process schematic
The workpieces to be joined are treated with cleaning flux. Then the workpiece is mounted in the workholding device and immersed in the molten solder for 2 to 12 seconds. The workpiece is often agitated to aid the flow of the solder. The workpiece holder must allow an inclination of so that the solder may run off to ensure a smooth finish.
Workpiece geometry
This process is generally limited to all-metal work pieces, although other materials, such as circuit boards can also tolerate momentary contact with the hot molten solder without damage.
Setup and equipment
There is not much equipment or setup needed for dip soldering. All that is needed is the solder pot with its temperature control panel, a bath of molten solder, and the work-holding device. Usually the work-holding device is custom made for each respective workpiece for either manual or automated dipping.
Solderability
Some materials are easier to solder than others. Copper, silver, and gold are easy to solder. Iron and nickel are a little more difficult. Titanium, magnesium, cast irons, steels, ceramics, and graphites are hard to solder. However, if they are first plated they are more easily soldered. An example of this is tin-plating, in which a steel is sheet coated with tin so that it can be soldered more easily.
Applications
Dip soldering is used extensively in the electronics industry. However, they have a limited service use at elevated temperatures because of the low melting point of the filler metals. Soldered materials do not have much strength and are therefore not used for load-bearing.
References
Further reading
Kalpakjian, Serope, and Steven R. Schmid. Manufacturing Engineering and Technology: Fifth Edition. Upper Saddle River, NJ: Pearson Education, 2006
Electronics manufacturing
Soldering | Dip soldering | [
"Engineering"
] | 757 | [
"Electronic engineering",
"Electronics manufacturing"
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12,115,708 | https://en.wikipedia.org/wiki/Quality%20%28physics%29 | In response theory, the quality of an excited system is related to the number of excitation frequencies to which it can respond. In the case of a homogeneous, isotropic system, the quality is proportional to the FWHM.
This sense of the phrase is the precursor of the usage of the word in music theory. In music theory, quality is the number of harmonics of a fundamental frequency of an instrument (the higher the quality, the richer the sound).
See also
Q factor
Physical quantities | Quality (physics) | [
"Physics",
"Mathematics"
] | 104 | [
"Physical phenomena",
"Quantity",
"Physical quantities",
"Physical properties"
] |
12,116,884 | https://en.wikipedia.org/wiki/Rigid%20needle%20adapter | A rigid needle adapter enables electrical contact of finest structures on printed circuit boards, typically for high-volume testing.
The spring probes are arranged in a compact grid in the raster head so that up to 280 spring probes per square centimeter can be integrated. The rigid needles are moved to the desired contact point by the spring probes in the rigid needle adapter. Contacting pitch down to 150 μm can be tested by the movement of the rigid needles.
References
Printed circuit board manufacturing | Rigid needle adapter | [
"Engineering"
] | 102 | [
"Electrical engineering",
"Electronic engineering",
"Printed circuit board manufacturing"
] |
12,116,946 | https://en.wikipedia.org/wiki/Lawn%20dart%20effect | In aviation, the lawn dart effect occurs when fighter aircraft pilots accelerate horizontally at more than 1 standard gravity. The effect occurs when such extreme stimulation to the vestibular system leads to the perception that the aircraft is climbing, prompting the pilot to lower the aircraft's pitch attitude, or drop the nose.
See also
Sensory illusions in aviation
Lawn darts
G-force
References
Perception
Airspeed | Lawn dart effect | [
"Physics"
] | 78 | [
"Wikipedia categories named after physical quantities",
"Airspeed",
"Physical quantities"
] |
12,117,226 | https://en.wikipedia.org/wiki/Frontier%20Wire%20%28Libya%29 | The Frontier Wire was a obstacle in Italian Libya, along the length of the border of British-held Egypt, running from El Ramleh, in the Gulf of Sollum (between Bardia and Sollum) south to Jaghbub parallel to the 25th meridian east, the Libya–Egypt and Libya–Sudan borders. The frontier wire and its line of covering forts was built by the Italians during the Second Italo-Senussi War (1923–1931), as a defensive system to contain the Senussi population, who crossed from Egypt during their resistance against Italian colonisers.
From the Italian declaration of war on 10 June 1940 until the conquest of Libya by the British in 1942, it was the scene of military engagements between Italian, British and German forces as the fighting ebbed and flowed across the frontier. While the installation was reasonably effective against the poorly equipped Senussi, it was ineffective against the well-equipped conventional army fielded by the British.
Background
In 1922, Benito Mussolini continued the of Libya, in the Second Italo-Sanussi War The frontier wire was built by the Italian army under General Rodolfo Graziani in the early 1930s, to repress Senussi resistance against the Italian colonisation, by hindering the movement of Senussi fighters and materials from Egypt. The wire comprised four lines of high stakes in concrete bases, laced with barbed wire long, just inside the border from El Ramleh on the Gulf of Sollum, past Fort Capuzzo to Sidi Omar, then south, slightly to the west of the 25th meridian east, the border with Egypt and Sudan. Three large forts at Amseat (Fort Capuzzo), Scegga (Fort Maddalena) and Giarabub and six smaller ones at El Ramleh on the Gulf of Sollum, Sidi Omar, Sceferzen, Vescechet, Garn ul Grein, and El Aamara were built along the wire. The wire was patrolled using aircraft and armoured cars from the forts, by the Italian army and border guards, who attacked anyone seen in the frontier zone.
Prelude
Frontier skirmishes
British patrols closed up to the frontier wire on 11 June 1940 and began to dominate the area, harass the garrisons of the frontier forts and set ambushes along the (renamed later in 1940) and inland tracks. Some Italian troops were unaware that war had been declared and seventy were captured during the day, on the track to Sidi Omar. British patrols ranged north to the , on the coast between Bardia and Tobruk, west to Bir el Gubi and south to Giarabub. Italian reinforcements then arrived at the frontier, began to reconnoitre, improved the frontier defences and recaptured Fort Capuzzo. On 13 August, the British raids were stopped to conserve the serviceability of vehicles and the Support Group of the 7th Armoured Division took over, to observe the wire for from Sollum south to Fort Maddalena, ready to fight delaying actions against an Italian advance.
Fort Capuzzo
Fort Capuzzo () was one of the forts built near the border with Egypt and the frontier wire, part of a system of frontier control built in the early 1930s. The ran south from Bardia to Fort Capuzzo, west of the port of Sollum in Egypt, then east across the frontier, down the escarpment to the coast. The fort was built with four crenellated stone walls around a yard with living quarters on the edges. A track ran south from the fort, just west of the frontier wire and the border, to Sidi Omar, Fort Maddalena and Giarabub. On 14 June, after the Italian declaration of war on Britain four days earlier, the 7th Hussars and elements of the 1st Royal Tank Regiment, supported by Gloster Gladiator fighters of 33 Squadron Royal Air Force (RAF) and Bristol Blenheim bombers of 211 Squadron captured Fort Capuzzo as the 11th Hussars took Fort Maddalena, about further south.
The fort was not occupied long, for lack of troops and equipment, but demolition parties visited each night to destroy Italian ammunition and vehicles. The Italians reoccupied Fort Capuzzo and held it with part of the 2nd Blackshirt Division (28 October) ( Francesco Argentino). On 29 June, the Maletti Group repulsed British tanks with its artillery and then defeated a night attack. During the frontier skirmishes from the British claimed to have inflicted for a loss of On 16 December, during Operation Compass the 4th Armoured Brigade of the Western Desert Force captured Sidi Omar and the Italians withdrew from Sollum, Fort Capuzzo and the other frontier forts. Number Supply Depot was established at the fort for the 7th Armoured Division.
Sidi Omar
The fortified camp at Sidi Omar was ringed with barbed wire, trenches and minefields. On 11 June 1940, the 11th Hussars in Rolls-Royce and Morris CS9 armoured cars closed up to the frontier wire, crossed during the night and exchanged fire with the garrison at Sidi Omar. Sidi Omar was captured on 16 December, during Operation Compass by the 7th Hussars, 2nd Royal Tank Regiment (2nd RTR) and the 4th Royal Horse Artillery (4th RHA). The British bombarded the fort, then tanks charged the fort and one broke through the wall. After a second tank drove through the hole in the wall, the garrison began to surrender. The Italians had concentrated their firepower on the east wall facing Egypt and had been surprised by an attack from the west. The fall of the fort left the way clear for the British to send reinforcements and supplies to the forces further north on the coast, free from the possibility of attack from the inland flank.
Nezuet Ghirba
On 16 June 1940, two days after the loss of Fort Capuzzo and Fort Maddalena and six days after the Italian declaration of war, the 10th Army formed (Colonel Lorenzo D’Avanzo) with orders to end British penetrations of the frontier wire near Fort Capuzzo. The comprised a Libyan motorised battalion from the 1st Libyan Division, the 3rd Company of the IX Light Tank Battalion with and the motorised Libyan 17th Battery, IV Group with four 77/28 guns. was sent from Gabr Saleh towards the area from Sidi Omar−Fort Capuzzo, to clear the area of British raiding parties. As advanced toward Fort Capuzzo in two columns, British forces in the vicinity were ordered to withdraw across the border.
Two 11th Hussar armoured cars attacked the Italian column at Nezuet Ghirba, about west of Sidi Omar, on a plain devoid of cover, along the route of the smaller Italian column. D’Avanzo, formed a defensive square, with the four guns at the corners, the infantry along the sides and the twelve L3 light tanks patrolling outside. The British reinforced the 11th Hussars with the 7th Hussars armoured cars and a mixed force of light tanks, a cruiser squadron of Cruiser Mk I tanks and an artillery battery. The Italian tanks charged forward ahead of the artillery and infantry and were knocked out. The British then circled the Italian square, firing at the lorries and infantry; after the second circuit, the Italian artillery opened fire. The Italian gunners had only high explosive ammunition and the British concentrated on the guns at each corner. Lacking cover the Italian gunners were soon shot down and then the infantry broke. The British destroyed twelve light tanks, the four guns and killed or captured the infantry.
Fort Maddalena
A Squadron of the 11th Hussars made three gaps in the wire on the night of 11 June, cut telephone poles on the Italian side and skirmished around the fort. On 13 June, an armoured car troop attacked the fort and was repulsed by the garrison, then attacked by Italian aircraft as they retreated. The 11th Hussars reconnoitred again on 14 June, with part of the 4th Armoured Brigade ready to attack but the garrison surrendered, the British taking and destroying equipment, then moving on to set an ambush on the .
Siege of Giarabub
The Siege of Giarabub (now Jaghbub) in Libya, took place between the WDF and the Italian garrison. In the aftermath of , the Italian invasion of Egypt by the 10th Army (10ª ) from 9 to 16 September 1940, Operation Compass (9–16 December) by the WDF, the Battle of Sidi Barrani and the pursuit of the 10th Army into Cyrenaica the fortified Italian position at the Al Jaghbub Oasis was besieged by part of the 6th Australian Division from December 1940 to 21 March 1941.
The 6th Australian Divisional Cavalry Regiment (6th ADCR) began the siege in December 1940 and isolated the oasis, leaving the garrison dependent on the (Italian Royal Air Force) for supplies. Air transport proved insufficient and hunger prompted many of the locally recruited troops to desert. After being reinforced by the 2/9th Australian Battalion and a battery of the 4th RHA, the Australians attacked and captured Giarabub from The Australians left behind a salvage party and withdrew from the oasis the next day, just before the Italo-German counter-offensive, Operation Sonnenblume, which recaptured Cyrenaica.
Post war
After the Allied conquest in 1943, Tripolitania and Cyrenaica were ruled under the British Military Administration of Libya until independence in 1951, as a kingdom under Muhammad Idris bin Muhammad al-Mahdi as-Senussi (King Idris of Libya) and the frontier wire disappeared into obscurity.
Orders of battle
Frontier wire fort garrisons, June 1940
Details taken from Christie (1999) unless specified.
Commander in Chief (Italian North Africa) (Marshal) Italo Balbo
Giarabub
Infantry company
Auto-MG company
3rd Libyan Fortress Machine Gun Battalion
Four companies fixed MGs
Reinforced AT Platoon (6 × 47/32 M35 anti-tank guns
Reinforced AA Platoon (6 × 20 mm Breda Model 35 AA guns)
Infantry Gun Platoon (2 × 65/17 modello 13 guns)
Bir Scegga (Fort Maddalena)
Infantry company
MG Company
AT Platoon (4 × 47/32 AT guns)
AA Platoon (4 × AA guns)
El Garn ul Grein
Infantry company
MG platoon
AT Platoon (4 × 47/32 M35 AT guns)
AA Platoon (4 × AA guns)
Gialo (Oasis Garrison)
MG Battalion
Libyan Replacement Battalion
AT Company (12 × 47/32 AT guns)
AA Platoon (4 × AA guns)
Saharan Company
Western Desert Force, June 1940
Commander-in-Chief Middle East, General Sir Archibald Wavell
Western Desert Force (commander, Lieutenant General R. N. O’Connor)
7th Armoured Division (commander, Major-General M. O’Moore)
4th Armoured Brigade, Mersa Matruh
1st Royal Tank Regiment
6th Royal Tank Regiment
7th Armoured Brigade, Sidi Sulieman
7th Hussars
8th Hussars
Support Group. (Motorized Infantry Brigade) Sidi Barrani
1st King's Royal Rifle Corps Battalion
2nd Motor Battalion The Rifle Brigade
3rd Battalion Coldstream Guards
1st Royal Northumberland Fusiliers
3rd Regiment Royal Horse Artillery
F Battery, 4th Royal Horse Artillery
11th Hussars (attached to Support Group from 7th Armoured Brigade) Forward at Sidi Barrani with operations on the Libyan-Egyptian Border
Cairo Infantry Brigade Garrison for Mersa Matruh
Other Commonwealth Forces in Egypt
4th Indian Division (less one infantry brigade) Nile Delta
5th Indian Infantry Brigade
11th Indian Infantry Brigade
Divisional Troops
6th Australian Division (forming, Nile delta)
2nd New Zealand Division (forming, Nile delta)
See also
Fort Capuzzo
Italian Libya
History of Libya as Italian Colony
Notes
Footnotes
References
Books
Theses
Websites
Further reading
External links
British Official History: The Mediterranean and Middle East Vol I, Ch 6: Italy Declares War
"Peace in Libya". Time. 8 February 1932.
The wire at Fort Maddalena
Photomontage of the frontier wire at Jaghbub, 2009
Colonial Soldiers in Italian Counter-Insurgency Operations in Libya, 1922–32
Italian Libya
Fortifications in Libya
World War II defensive lines
Historic defensive lines
Italian fascist architecture
Fortification (obstacles)
World War II sites in Libya
World War II sites of Fascist Italy
Italy–Libya relations | Frontier Wire (Libya) | [
"Engineering"
] | 2,506 | [
"World War II defensive lines",
"Fortification lines",
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12,117,291 | https://en.wikipedia.org/wiki/Maintenance%20engineering | Maintenance Engineering is the discipline and profession of applying engineering concepts for the optimization of equipment, procedures, and departmental budgets to achieve better maintainability, reliability, and availability of equipment.
Maintenance, and hence maintenance engineering, is increasing in importance due to rising amounts of equipment, systems, machineries and infrastructure. Since the Industrial Revolution, devices, equipment, machinery and structures have grown increasingly complex, requiring a host of personnel, vocations and related systems needed to maintain them. Prior to 2006, the United States spent approximately US$300 billion annually on plant maintenance and operations alone. Maintenance is to ensure a unit is fit for purpose, with maximum availability at minimum costs. A person practicing maintenance engineering is known as a maintenance engineer.
Maintenance engineer's description
A maintenance engineer should possess significant knowledge of statistics, probability, and logistics, and in the fundamentals of the operation of the equipment and machinery he or she is responsible for. A maintenance engineer should also possess high interpersonal, communication, and management skills, as well as the ability to make decisions quickly.
Typical responsibilities include:
Assure optimization of the maintenance organization structure
Analysis of repetitive equipment failures
Estimation of maintenance costs and evaluation of alternatives
Forecasting of spare parts
Assessing the needs for equipment replacements and establish replacement programs when due
Application of scheduling and project management principles to replacement programs
Assessing required maintenance tools and skills required for efficient maintenance of equipment
Assessing required skills for maintenance personnel
Reviewing personnel transfers to and from maintenance organizations
Assessing and reporting safety hazards associated with maintenance of equipment
Maintenance engineering education
Institutions across the world have recognised the need for maintenance engineering. Maintenance engineers usually hold a degree in mechanical engineering, industrial engineering, or other engineering disciplines. In recent years specialised bachelor and master courses have developed. The bachelor degree program in maintenance engineering at the German-Jordanian University in Amman is addressing the need, as well as the master's program in maintenance engineering at Luleå University of Technology. With an increased demand for Chartered Engineers, The University of Central Lancashire in United Kingdom has developed a MSc in maintenance engineering currently under accreditation with the Institution of Engineering and Technology and a top-up Bachelor of Engineering with honour degree for technicians holding a Higher National Diploma and seeking a progression in their professional career.
See also
Aircraft maintenance engineering
Asset management
Auto mechanic
Civil engineer
Computerized maintenance management system
Computer repair technician
Electrician
Electrical Technologist
Industrial Engineering
Marine fuel management
Mechanic
Millwright (machinery maintenance)
Maintenance, repair and operations (MRO)
Reliability centered maintenance (RCM)
Reliability engineering
Preventive maintenance
Product lifecycle management
Stationary engineer
Total productive maintenance (TPM)
Six Sigma for maintenance
Associations
INFORMS
Institute of Industrial Engineers
References
School of Applied Technical Sciences - Maintenance Engineering
Industrial engineering
Industrial occupations
Maintenance
Engineering disciplines
Engineering occupations
Reliability engineering
Product lifecycle management
Mechanical engineering | Maintenance engineering | [
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12,118,054 | https://en.wikipedia.org/wiki/Laplace%20expansion%20%28potential%29 | In physics, the Laplace expansion of potentials that are directly proportional to the inverse of the distance (), such as Newton's gravitational potential or Coulomb's electrostatic potential, expresses them in terms of the spherical Legendre polynomials. In quantum mechanical calculations on atoms the expansion is used in the evaluation of integrals of the inter-electronic repulsion.
Formulation
The Laplace expansion is in fact the expansion of the inverse distance between two points. Let the points have position vectors and , then the Laplace expansion is
Here has the spherical polar coordinates and has with homogeneous polynomials of degree . Further r< is min(r, r′) and r> is max(r, r′). The function is a normalized spherical harmonic function. The expansion takes a simpler form when written in terms of solid harmonics,
Derivation
The derivation of this expansion is simple. By the law of cosines,
We find here the generating function of the Legendre polynomials :
Use of the spherical harmonic addition theorem
gives the desired result.
Neumann expansion
A similar equation has been derived by Carl Gottfried Neumann that allows expression of in prolate spheroidal coordinates as a series:
where and are associated Legendre functions of the first and second kind, respectively, defined such that they are real for . In analogy to the spherical coordinate case above, the relative sizes of the radial coordinates are important, as and .
References
Potential theory
Atomic physics
Rotational symmetry | Laplace expansion (potential) | [
"Physics",
"Chemistry",
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"Atomic",
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13,678,080 | https://en.wikipedia.org/wiki/History%20of%20the%20iPhone | The history of the iPhone by Apple Inc. spans from the early 2000s to about 2010. The first iPhone was unveiled at Macworld 2007 and released later that year. By the end of 2009, iPhone models had been released in all major markets.
Genesis of the iPhone
The idea of an Apple phone came from Jean-Marie Hullot, a software engineer who worked at NeXT, and later, Apple. Initially, making an Apple phone was not favored by CEO Steve Jobs, but eventually Hullot was able to convince him. The first team was created in Paris; however, it was not until a few years later that he took the project more seriously: the French engineers were asked to work back in the US, but Hullot declined and resigned from Apple with his team. Another engineer, Henri Lamiraux, became the new head of the project with Scott Forstall, to develop the iPhone software.
Initial development
Initially, the iPhone started from a conflict between Steve Jobs and his brother-in-law working at Microsoft, then convinced by a French high-level engineer, Jean-Marie Hullot, working for Apple France to do so. The project within Apple Inc. for developing the iPhone began with a request in 2004 from CEO Steve Jobs to the company's hardware engineer Tony Fadell, software engineer Scott Forstall and design engineer Sir Jonathan Ive to work on the highly confidential "Project Purple".
While pitting two teams of engineers led by Fadell and Forstall, Jobs decided to investigate the use of touchscreen devices and tablet computers (which later came to fruition with the iPad). Jobs ended up pushing for a touch-screen device that many have noted has similarities to Apple's previous touch-screen portable device, the Newton MessagePad. Like the MessagePad, the iPhone is nearly all screen. Its form factor is credited to Apple's Chief Design Officer, Jonathan Ive.
Jobs expressed his belief that tablet PCs and traditional PDAs were not good choices as high-demand markets for Apple to enter, despite receiving many requests for Apple to create another PDA. In 2002, after the iPod launched, Jobs realized that the overlap of mobile phones and music players would force Apple to get into the mobile phone business. After seeing millions of Americans carrying separate BlackBerrys, phones, and Apple's iPod MP3 players; he felt eventually consumers would prefer just one device.
Jobs also saw that as cell phones and mobile devices would keep amassing more features, they will be challenging the iPod's dominance as a music player. To protect the iPod new product line, which by the start of 2007 was responsible for 48% of all of Apple's revenue, Jobs decided he would need to venture into the wireless world. So at that time, instead of focusing on a follow-up to their Newton PDA, Jobs had Apple focus on the iPod. Jobs also had Apple develop the iTunes software, which can be used to synchronize content with iPod devices. iTunes had been released in January 2001.
Several enabling technologies made the iPhone possible. These included lithium-ion batteries that were small and powerful enough to power a mobile computer for a reasonable amount of time; multi-touch screens; energy-efficient but powerful CPUs, such as those using the ARM architecture; mobile phone networks; and web browsers. Apple approached glass manufacturer Corning in 2005 to investigate the possibility of a thin, flexible, and transparent material that could avoid the problem of metal keys scratching up phone screens. Corning reactivated some old research material that had not yet found an application to produce Gorilla Glass.
Beta to production and announcement
In an effort to bypass the carriers, Jobs approached Motorola. On September 7, 2005, Apple and Motorola collaborated to develop the Motorola ROKR E1, the first mobile phone to use iTunes. Steve Jobs was unhappy with the ROKR, among other deficiencies, the ROKR E1's firmware limited storage to only 100 iTunes songs to avoid competing with Apple's iPod nano. iTunes Music Store purchases could also not be downloaded wirelessly directly into the ROKR E1 and had to be done through a PC sync. Apple therefore decided to develop its own phone, which would incorporate the iPod's musical functions into a smartphone.
Feeling that having to compromise with a non-Apple designer (Motorola) prevented Apple from designing the phone they wanted to make, Apple discontinued support for the ROKR in September 2006, and, after creating a deal with AT&T (at the time still called Cingular), released a version of iTunes that included references to an as-yet unknown mobile phone that could display pictures and video. This turned out to be the first iPhone (iPhone 2G).
On January 9, 2007, Steve Jobs announced the first iPhone at the Macworld convention, receiving substantial media attention. On June 11, 2007, Apple announced at the Apple's Worldwide Developers Conference that the iPhone would support third party applications using the Safari engine. Third parties would be able to create Web 2.0 applications, which users could access via the Internet. Such applications appeared even before the release of the iPhone; the first of these, called OneTrip, was a program meant to keep track of users' shopping lists.
On June 29, 2007, the first iPhone was released. The iPod Touch, which came with an iPhone-style touchscreen to the iPod range, was also released later in 2007. The iPad followed in 2010.
Connection to AT&T
When Apple announced the iPhone on January 9, 2007, it was sold only with AT&T (formerly Cingular) contracts in the United States. After 18 months of negotiations, Steve Jobs reached an agreement with the wireless division of AT&T to be the iPhone's exclusive carrier. Consumers were unable to use any other carrier without unlocking their device.
Apple retained control of the design, manufacturing and marketing of the iPhone. Since some customers were jailbreaking their iPhones to leave their network, AT&T began charging them a $175 early-termination fee for leaving before the end of their contract.
Court cases
Questions arose about the legality of Apple's arrangement after the iPhone was released. Two class-action lawsuits were filed against the company in October 2007: one in Federal court and the other in state court. According to the suits, Apple's exclusive agreement with AT&T violated antitrust law.
The state-court suit, filed by the law office of Damian R. Fernandez on behalf of California resident Timothy P. Smith, sought an injunction barring Apple from selling iPhones with a software lock and $200 million in damages. In Smith v. Apple Inc., the plaintiffs said that Apple failed to disclose to purchasers its five-year agreement with AT&T when they bought iPhones with a two-year contract and cited the Sherman Act's prohibition of monopolies.
The second case was filed in the United States District Court for the Northern District of California. The plaintiff, Paul Holman, filed a complaint against Apple and AT&T Mobility that he could not switch carriers or change SIM cards without losing iPhone improvements to which he was entitled. Holman also cited a Sherman Act violation by the defendants. On July 8, 2010, the case was affirmed for class certification. On December 9 the court ordered a stay on the case, awaiting the Supreme Court's decision in AT&T v. Concepcion (disputed whether the state's basic standards of fairness were met by a clause in AT&T's contract limiting complaint resolution to arbitration). On April 27, 2011, the Supreme Court ruled that AT&T met the state's fairness standards.
In 2017, Apple was sued after they admitted to slowing down older phone models. The plaintiffs, Stefan Bogdanovich and Dakota Speas, filed the lawsuit when their iPhone 6S was slower after an update. The plaintiffs were entitled to compensation due to the interferences and the economic damages they suffered.
United States release
On June 28, 2007, during an address to Apple employees, Steve Jobs announced that all full-time Apple employees and those part-time employees who had been with the company for at least one year would receive a free iPhone. Employees received their phones in July after the initial demand for the iPhone subsided.
Initially priced at $499 () and $599 () for the 4 GB models and 8 GB models respectively, the iPhone went on sale on June 29, 2007. Apple closed its stores at 2:00pm local time to prepare for the 6:00pm iPhone launch, while hundreds of customers lined up at stores nationwide.
In the US and some other countries, iPhones could be acquired only with a credit card, preventing completely anonymous purchases of iPhones. At the time, there was no way to opt out of the bundled AT&T data plan. At first, iPhones could not be added to an AT&T Business account, and any existing business account discounts could not be applied to an iPhone AT&T account. AT&T changed these restrictions in late January 2008.
The Associated Press also reported in 2007 that some users were unable to activate their phones because, according to AT&T, "[a] high volume of activation requests [was] taxing the company's computer servers."
Early estimates by technology analysts estimated sales of between 250,000 and 700,000 iPhones in the first weekend alone, with strong sales continuing after the initial weekend. As part of their quarterly earnings announcement, AT&T reported that 146,000 iPhones were activated in the first weekend. Though this figure does not include units that were purchased for resale on eBay or otherwise not activated until after the opening weekend, it is still less than most initial estimates. It is also estimated that 95% of the units sold were the 8 GB model.
Oversized bills
Stories of unexpected billing issues began to circulate in blogs and the technical press a little more than a month after iPhone's heavily advertised and anticipated release. The 300-page iPhone bill in a box received by iJustine on Saturday, August 11, 2007 became the subject of a viral video, posted by the following Monday, which quickly became an Internet meme. This video clip brought the voluminous bills to the attention of the mass media. Ten days later, after the video had been viewed more than 3 million times on the Internet, and had received international news coverage, AT&T sent iPhone users a text message outlining changes in its billing practices.
Price drop outcry
On September 5, 2007, the 4 GB model was discontinued, and the 8 GB model price was cut by a third, from $599 USD to $399 USD. Those who had purchased an iPhone in the 14-day period before the September 5, 2007, announcement were eligible for a $200 "price protection" rebate from Apple or AT&T. However, it was widely reported that some who bought between the June 29, 2007, launch and the August 22, 2007, price protection kick-in date complained that this was a larger-than-normal price drop for such a relatively short period and accused Apple of unfair pricing.
In response to customer complaints, on September 6, 2007, Apple CEO Steve Jobs wrote in an open letter to iPhone customers that everyone who purchased an iPhone at the higher price "and who is not receiving a rebate or other consideration", would receive a $100 credit to be redeemed towards the purchase of any product sold in Apple's retail or online stores.
iPhone 3G pricing model changes
With the July 11, 2008, release of the iPhone 3G, Apple and AT&T changed the US pricing model from the previous generation. Following the de facto model for mobile phone service in the United States, AT&T would subsidize a sizable portion of the upfront cost for the iPhone 3G, followed by charging moderately higher monthly fees over a minimum two-year contract.
iPhone 4 CDMA release
There had been ongoing speculation in the United States that Apple might offer a CDMA-compatible iPhone for Verizon Wireless. This speculation increased on October 6, 2010, when The Wall Street Journal reported that Apple would begin producing a CDMA-compatible iPhone, with such a model going on sale in early 2011.
On January 11, 2011, Verizon announced during a media event that it had reached an agreement with Apple and would begin selling a CDMA iPhone 4. The Verizon iPhone went on sale on February 10, 2011. The CDMA version was a bespoke model, lacking a SIM slot and with a revised metal chassis, the design of which would be reused on the iPhone 4S.
During Apple's official unveiling of iPhone 4S on October 4, 2011, it was announced that Sprint would begin carrying the reconfigured CDMA iPhone 4 and iPhone 4S in the US on October 14. Cricket Wireless announced on May 31, 2012, that it would become the first prepaid carrier in the US to offer iPhone 4 and iPhone 4S, beginning June 22, 2012. A week later, Virgin Mobile USA became the second American prepaid carrier to offer iPhone 4 and 4S, announcing plans to release the phones on June 29, 2012. T-Mobile USA's inability to provide iPhone to customers raised its subscription churn rate, decreased the percentage of lucrative postpaid customers, and contributed to parent Deutsche Telekom's decision to sell it to AT&T in March 2011, although AT&T canceled the deal in December 2011 because of antitrust concerns. T-Mobile began offering iPhone on April 12, 2013.
iPhone 5 and the Lightning connector
With the release of the iPhone 5 on September 21, 2012, Apple introduced a thinner and stronger design for the iPhone. This design included the availability of the colors: black, white, grey, and gold; gold being used for the first time with this iteration of the iPhone. Sapphire materials were used for home button and the camera to help resist scratches and fingerprints, while anodized aluminum and ceramic glass were used for the phone's body. Support for 4G-LTE internet was also added.
Apple abandoned the 30Pin Dock in favor of the Lightning Dock. This change was a surprise to business owners and consumers alike as this swap was unexpected. This was later changed with the release of iPhone 15, which switched to USB-C ports.
International release timeline
The international release of iPhone was staggered over several months. Today, the iPhone is available in most countries.
† iPhone offered by multiple carriers under contract from Apple (country not carrier-exclusive)
‡ iPhone offered without contract and without carrier lock
§ MVNO with O2
Activation and SIM lock bypassing
Intellectual property
Apple has filed more than 200 patent applications related to the technology behind the iPhone.
LG Electronics claimed the design of the iPhone was copied from the LG Prada. Woo-Young Kwak, head of LG Mobile Handset R&D Center, said at a press conference: "we consider that Apple copied Prada phone after the design was unveiled when it was presented in the iF Design Award and won the prize in September 2006." Conversely, the iPhone has also inspired its own share of high-tech clones.
On September 3, 1993, Infogear filed for the U.S. trademark "I PHONE" and on March 20, 1996, applied for the trademark "IPhone". "I Phone" was registered in March 1998, and "IPhone" was registered in 1999. Since then, the I PHONE mark had been abandoned. Infogear trademarks cover "communications terminals comprising computer hardware and software providing integrated telephone, data communications and personal computer functions" (1993 filing), and "computer hardware and software for providing integrated telephone communication with computerized global information networks" (1996 filing).
In 2000, Infogear filed an infringement claim against the owners of the iPhones.com domain name. The owners of the iPhones.com domain name challenged the infringement claim in the Northern District Court of California. In June 2000, Cisco Systems acquired Infogear, including the iPhone trademark. In September 2000, Cisco Systems settled with the owners of iPhones.com and allowed the owners to keep the iPhones.com domain name along with intellectual property rights to use any designation of the iPhones.com domain name for the sale of cellular phones, cellular phones with Internet access (WAP PHONES), handheld PDAs, storage devices, computer equipment (hardware/software), and digital cameras (hardware/software). The intellectual property rights were granted to the owners of the iPhones.com domain name by Cisco Systems in September 2000.
In October 2002, Apple applied for the "iPhone" trademark in the United Kingdom, Australia, Singapore, and the European Union. A Canadian application followed in October 2004, and a New Zealand application in September 2006. As of October 2006, only the Singapore and Australian applications had been granted.
In September 2006, a company called Ocean Telecom Services applied for an "iPhone" trademark in the United States, United Kingdom, and Hong Kong, following a filing in Trinidad and Tobago. As the Ocean Telecom trademark applications use exactly the same wording as the New Zealand application of Apple, it is assumed that Ocean Telecom is applying on behalf of Apple. The Canadian application was opposed in August 2005, by a Canadian company called Comwave who themselves applied for the trademark three months later. Comwave has been selling VoIP devices called iPhone since 2004.
Shortly after Steve Jobs' January 9, 2007, announcement that Apple would be selling a product called iPhone in June 2007, Cisco issued a statement that it had been negotiating trademark licensing with Apple and expected Apple to agree to the final documents that had been submitted the night before. On January 10, 2007, Cisco announced it had filed a lawsuit against Apple over the infringement of the trademark iPhone, seeking an injunction in federal court to prohibit Apple from using the name. In February 2007, Cisco claimed that the trademark lawsuit was a "minor skirmish" that was not about money, but about interoperability.
On February 2, 2007, Apple and Cisco announced that they had agreed to temporarily suspend litigation while they held settlement talks, and subsequently announced on February 20, 2007, that they had reached an agreement. Both companies will be allowed to use the "iPhone" name in exchange for "exploring interoperability" between their security, consumer, and business communications products.
On October 22, 2009, Nokia filed a lawsuit against Apple for infringement of its GSM, UMTS and WLAN patents. Nokia alleges that Apple has been violating ten Nokia patents since the iPhone initial release. This and further lawsuits by Nokia were eventually settled.
In December 2010, Reuters reported that some iPhone and iPad users were suing Apple Inc. because some applications were passing user information to third-party advertisers without permission. Some makers of the applications such as Textplus4, Paper Toss, The Weather Channel, Dictionary.com, Talking Tom Cat and Pumpkin Maker have also been named as co-defendants in the lawsuit.
In August 2012, Apple won a smartphone patent lawsuit in the U.S. against Samsung, the world's largest maker of smartphones; however, on December 6, 2016, SCOTUS reversed the decision that awarded nearly $400 million to Apple and returned the case to Federal Circuit court to define the appropriate legal standard to define "article of manufacture" because it is not the smartphone itself but could be just the case and screen to which the design patents relate.
Legal battles over brand name
In Mexico, the trademark iFone was registered in 2003 by a communications systems and services company, iFone. Apple tried to gain control over its brand name, but a Mexican court denied the request. The case began in 2009, when the Mexican firm sued Apple. The Supreme Court of Mexico upheld that iFone is the rightful owner and held that Apple iPhone is a trademark violation.
In Brazil, the brand IPHONE was registered in 2000 by the company then called Gradiente Eletrônica S.A., now IGB Eletrônica S.A. According to the filing, Gradiente foresaw the revolution in the convergence of voice and data over the Internet at the time. The final battle over the brand name concluded in 2008. On December 18, 2012, IGB launched its own line of Android smartphones under the tradename to which it has exclusive rights in the local market. In February 2013, the Brazilian Patent and Trademark Office (known as "Instituto Nacional da Propriedade Industrial") issued a ruling that Gradiente Eletrônica, not Apple, owned the "iPhone" mark in Brazil. The "iPhone" term was registered by Gradiente in 2000, seven years before Apple's release of its first iPhone. This decision came three months after Gradiente Eletrônica launched a lower-cost smartphone using the iPhone brand. In June 2014, Apple won, for the second time, the right to use the brand name in Brazil. The court ruling determined that the Gradiente's registration does not own exclusive rights on the brand. Although Gradiente intended to appeal, with the decision Apple can use freely the brand without paying royalties to the Brazilian company.
In the Philippines, Solid Group launched the MyPhone brand in 2007. Stylized as "my|phone", Solid Broadband filed a trademark application of that brand. Apple later filed a trademark case at the Intellectual Property Office of the Philippines (IPOPHL) against Solid Broadband's MyPhone for "confusingly similar" to the iPhone and that it may likely "deceive" or "cause confusion" among consumers. Apple lost the trademark battle to Solid Group in a 2015 decision made by IPO director Nathaniel Arevalo, who also reportedly said that it was unlikely that consumers would be confused between the "iPhone" and the "MyPhone". "This is a case of a giant trying to claim more territory than what it is entitled to, to the great prejudice of a local 'Pinoy Phone' merchant who has managed to obtain a significant foothold in the mobile phone market through the marketing and sale of innovative products under a very distinctive trademark", Arevalo later added.
See also
History of Apple Inc.
History of mobile phones
Timeline of Apple Inc. products
Timeline of iPhone models
Timeline of iOS devices
References
Further reading
IPhone
iPhone
iPhone | History of the iPhone | [
"Technology"
] | 4,552 | [
"Science and technology studies",
"History of science and technology",
"History of technology"
] |
13,678,647 | https://en.wikipedia.org/wiki/Node%20%28autonomous%20system%29 | The behaviour of a linear autonomous system around a critical point is a node if the following conditions are satisfied:
Each path converges to the or away from the critical point (dependent of the underlying equation) as (or as ). Furthermore, each path approaches the point asymptotically through a line.
References
Ordinary differential equations | Node (autonomous system) | [
"Mathematics"
] | 68 | [
"Mathematical analysis",
"Mathematical analysis stubs"
] |
13,679,173 | https://en.wikipedia.org/wiki/Electrochemical%20Society | The Electrochemical Society is a learned society (professional association) based in the United States that supports scientific inquiry in the field of electrochemistry solid-state science and related technology. The Society membership comprises more than 8,000 scientists and engineers in over 85 countries at all degree levels and in all fields of electrochemistry, solid-state science and related technologies. Additional support is provided by institutional members including corporations and laboratories.
ECS is a 501(c)(3) non-profit organization.
The Society publishes numerous journals including the Journal of The Electrochemical Society (the oldest peer-reviewed journal in its field), the Journal of Solid State Science and Technology, ECS Meeting Abstracts, ECS Transactions, and ECS Interface. The Society sponsors the ECS Monographs Series. These distinguished monographs, published by John Wiley & Sons, are the leading textbooks in their fields.
The ECS Digital Library on IOPscience encompasses over 160,000 journal and magazine articles and meeting abstracts. The Society supports open access through the Society’s initiative to make research freely available to world readers and free for authors to publish.
The Society has thirteen topic interest area divisions as well as regional sections in Asia, Europe, Latin America, the Middle East, North America, and Southern Asia; over 100 ECS student chapters are located in major universities in all of these regions as well as Eastern Europe and South Africa. Student members benefit from exposure to experts in their fields, sharing research, volunteer activities, and career development.
ECS administers numerous international awards and supports STEM educational and outreach efforts.
History
The Electrochemical Society was founded in 1902 in Philadelphia, PA. At the beginning, ECS was called the American Electrochemical Society.
The 19th century saw many applications of electricity to chemical processes and chemical understanding. Bridging the gap between electrical engineering and chemistry led people in industrial and academic circles to search for a new forum to discuss developments in the burgeoning field of electrochemistry.
The original constitution of the Society called for holding meetings and publishing papers presented there and the ensuing discussions. In 1902 the Society ushered in a new publication, Transactions of the American Electrochemical Society. In 1907 the first “local” section was formed at the University of Wisconsin. That same year, the American Electrochemical Society Bulletin was launched; it became the Journal of The Electrochemical Society in 1948.
In the 1920s, topical interest area divisions began to be founded, including the High Temperature Materials Division and the Electrodeposition Division. In 1930, the international nature of the Society was officially recognized by dropping “American” from the name. A new category of membership was started in 1941 to permit industrial companies to support the Society’s mission. ECS began fulfilling the need for critical textbooks with the publication of its second monograph, the Corrosion Handbook, by H. H. Uhlig in 1948.
Throughout the latter half of the 20th century, the Society continued to grow in size and importance, expanding the number of its publications, and the significance of the technical research unveiled at its meetings.
Over time, the Society’s members and publications’ authors have included many distinguished scientists and engineers. The Society’s original charter members included:
E. G. Acheson, who commercialized carborundum, an artificial graphite;
H. H. Dow, the founder of Dow Chemical Company;
C. M. Hall, the inventor of the Hall process for the manufacture of aluminum;
Edward Weston, the founder of Weston Instruments.
Thomas A. Edison joined the Society in 1903 and enjoyed membership for 28 years. In 1965, Gordon Moore's seminal prediction, Moore's Law, developed its roots within the Society. ECS has included numerous Nobel laureates among its members, most recently the three co-winners of the 2019 Nobel Prize in Chemistry. John B. Goodenough, M. Stanley Whittingham, and Akira Yoshino shared the prize “for the development of lithium-ion batteries.”
Meetings
The Society has hosted scientific technical meetings since 1902 including its biannual meetings in the spring and fall of each year.
Publications
ECS publishes peer-reviewed technical journals, proceedings, monographs, conference abstracts, and a quarterly news magazine.
Journals
Since 1902, the Society has published journals now available through ECS’s publishing partner.
Journal History
Several ECS journals which have ceased publication are now preserved as an archive. These archived publications are available through the Digital Library.
ECS Books & Monographs
Electrochemical Society Monograph Series
ECS Monographs provide accounts on specific topics in electrochemistry and solid-state science and technology. Since the 1940s, ECS and publishers have cooperated to publish titles in these fields.
Journal of The Electrochemical Society
JES is the flagship journal of The Electrochemical Society. Published continuously from 1902 to the present, JES is one of the most highly-cited journals in electrochemistry and solid-state science and technology.
ECS Journal of Solid State Science and Technology
JSS is a peer-reviewed journal covering fundamental and applied areas of solid-state science and technology, including experimental and theoretical aspects of the chemistry and physics of materials and devices.
ECS Interface
The Electrochemical Society Interface is a publication for those in the field of solid-state and electrochemical science and technology. Published quarterly, this four-color magazine contains technical articles about the latest developments in the field and presents news and information about and for Society members.
ECS Meetings Abstracts
ECS Meeting Abstracts contain extended abstracts of the technical papers presented at the ECS biannual meetings and ECS-sponsored meetings. This publication offers a first look into current research in the field. ECS Meeting Abstracts are freely available to all visitors to the ECS Digital Library.
ECS Transactions
ECST is the official conference proceedings publication of The Electrochemical Society. This publication features full-text content of proceedings from ECS meetings and ECS-sponsored meetings. ECST is a high-quality venue for authors and an excellent resource for researchers. The papers appearing in ECST are reviewed to ensure that submissions meet generally accepted scientific standards.
ECS Meeting Abstracts
ECS Meeting Abstracts contain extended abstracts of the technical papers presented at the ECS biannual meetings and ECS-sponsored meetings. This publication offers a first look into current research in the field. ECS Meeting Abstracts are freely available to all visitors to the ECS Digital Library.
Educational activities and programs
Awards
The society recognizes members for outstanding technical achievement in electrochemical and solid-state science and technology at various career levels, and recognizes exceptional service to the Society, through the ECS Honors & Awards Program—the international awards, medals, and prizes administered by the Society.
Starting in 1919, Honorary Membership was bestowed for outstanding contributions to the Society. ECS's most prestigious award, the Edward Goodrich Acheson Award, established in 1928, is presented in even-numbered years for "conspicuous contribution to the advancement of the objectives, purposes, and activities of the society".
Supporting students and early career scientists has been a long-held goal of The Electrochemical Society. The Norman Hackerman Young Author Award —established in 1928—is one of the first awards created by the Society. It is given for the best paper published in the Journal of The Electrochemical Society that year by a young author or co-authors. Recipients must be under 31 years of age. Among the significant talents recognized at an early age by this award is Nobel laureate, M. Stanley Whittingham, who received it in 1970.
The Olin Palladium Award (formerly the Palladium Medal Award), established in 1950, is presented in odd-numbered years to recognize "distinguished contributions to the field of electrochemical or corrosion science."
ECS honors members with the designation, Fellow of The Electrochemical Society for having made significant accomplishments to the fields of electrochemistry and solid state science and technology, and to the Society.
The Vittorio de Nora Award was established in 1971 to recognize distinguished contributions to the field of electrochemical engineering and technology.
Fellowships and grants
Through competitive fellowship stipends, ECS supports students and young professionals as they pursue new ideas and forge connections with professionals both within and outside the field.
Notable members
Notable members of The Electrochemical Society include numerous Nobel Prize laureates including the three co-winners of the 2019 Nobel Prize for Chemistry.
Thomas Edison: Edison became a member on April 4, 1903. Early members recall attending a meeting at Edison's home in the Society’s early days. Edison is often credited for inventing the phonograph, the motion picture camera, and the electric light bulb.
John B. Goodenough, M. Stanley Whittingham, and Akira Yoshino, all long-time ECS members, shared the 2019 Nobel Prize in Chemistry “for the development of lithium-ion batteries”.
Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura shared the 2014 Nobel Prize in Physics for “the invention of efficient blue light-emitting diodes, which has enabled bright and energy-saving white light sources”.
Jack Kilby’s invention of the integrated circuit earned him half of the 2000 Nobel Prize in Physics "for basic work on information and communication technology".
Steven Chu and William D. Phillips were co-recipients of the 1997 Nobel Prize in Physics “for the development of methods to cool and trap atoms with laser light”.
Richard Smalley shared the 1996 Nobel Prize in Chemistry “for the discovery of fullerenes”.
Rudolph A. Marcus won the 1992 Nobel Prize in Chemistry “for his contributions to the theory of electron transfer reactions in chemical systems".
Jean-Marie Lehn, an early innovator in the field of supramolecular chemistry, shared the 1987 Nobel Prize in Chemistry “for the development and use of molecules with structure-specific interactions of high selectivity”.
Gerd Binnig shared the 1986 Nobel Prize in Physics “for the design of the scanning tunneling microscope”.
Charles W. Tobias: A pioneer in the field of electrochemical engineering, Tobias made a long-lasting and far-reaching impact on the field of electrochemical science by forming the Chemical Engineering Department at UC Berkeley in 1947. He served as ECS president from 1970-1971.
Gordon E. Moore: The co-founder of Intel was known for his 1965 principle which made possible the delivery of more powerful and lower-costing semiconductor chips. This was later known as Moore's law.
Norman Hackerman: The internationally known expert in metal corrosion served as ECS president from 1957-1958. Hackerman is most recognized for developing the electrochemistry of oxidation.
Carl Wagner: Often referred to as the father of solid-state chemistry, Wagner's work on oxidation rate theory, counter diffusion of ions, and defect chemistry considerably advanced knowledge of how reactions proceed at the atomic level in the solid state. Wagner was the first recipient of the ECS Palladium Award in 1951.
Irving Langmuir: received the 1932 Nobel Prize in Chemistry “for his discoveries and investigations in surface chemistry”.
Edward Goodrich Acheson: The inventor of the Acheson process was a manufacturer of carborundum and graphite. The ECS Acheson Award was named in his honor in 1931.
Theodore William Richards: Richards, whose research helped confirm the existence of isotopes, received the 1914 Nobel Prize in Chemistry, “in recognition of his accurate determinations of the atomic weight of a large number of chemical elements”.
Willis R. Whitney: ECS president from 1911-1912, Whitney is most recognized among his many achievements for founding the research laboratory of the General Electric Company.
Leo Baekeland: Baekland, who served as ECS president in 1909, is most famous for inventing Bakelite in 1907. His entrepreneurial genius and inventive nature made Baekeland one of the most important players in chemical technology.
Herbert H. Dow: Among his most significant achievements, Dow founded the Dow Chemical Company in 1897. Dow Chemical funded the creation of the ECS Industrial Electrochemistry and Electrochemical Engineering Division H. H. Dow Memorial Student Achievement Award in his honor in 1990.
Edward Weston: Noted for his achievements in electroplating, Weston developed the electrochemical cell – named the Weston cell, for the voltage standard.
Charles Martin Hall: Hall, is best known for inventing an inexpensive process to produce aluminum, was one of the founders of Alcoa.
Lawrence Addicks (1878-1964) served as president of The Electrochemical Society from 1915 to 1916.
References
Electrochemistry
Chemistry societies
Scientific organizations established in 1902
1902 establishments in Pennsylvania
Scientific societies based in the United States | Electrochemical Society | [
"Chemistry"
] | 2,568 | [
"Chemistry societies",
"Electrochemistry",
"nan"
] |
13,679,557 | https://en.wikipedia.org/wiki/Asterisk%20Gateway%20Interface | Asterisk Gateway Interface (AGI) is a software interface and communications protocol for application level control of selected features of the Asterisk PBX.
AGI allows an external, user-written program, launched from the Asterisk dial plan via pipes to control telephony operations on its associated control and voice channels. It is similar to the CGI feature of web servers in allowing any language to be used for writing the external program which communicates with Asterisk via stdin and stdout.
While the initial feature set of AGI included only a procedural control of Asterisk operations via commands and response handshake, Enhanced AGI (EAGI) also provided out-of-band access to the incoming audio stream.
FastAGI is an extension to AGI which allows the external program to run at a separate network host to avoid the overhead of creating a new process for every call on the Asterisk server. It uses a TCP socket for communication to the external host which provides the function of an AGI service, in a manner of the client–server model. The default TCP port for FastAGI is 4573. Similar to HTTP uniform resource identifiers (URIs), FastAGI employs a URI format of .
The AGI feature set of Asterisk is implemented as an Asterisk loadable module (res_agi). The features may be access by a variety of application programming interfaces in various languages, such as phpagi, Perl AGI Library, CAGI, NanoAGI, and PyST
References
VoIP software | Asterisk Gateway Interface | [
"Engineering"
] | 326 | [
"Software engineering",
"Software engineering stubs"
] |
13,680,010 | https://en.wikipedia.org/wiki/Electric%20sonic%20amplitude | Electric sonic amplitude or electroacoustic sonic amplitude is an electroacoustic phenomenon that is the reverse to colloid vibration current. It occurs in colloids, emulsions and other heterogeneous fluids under the influence of an oscillating electric field. This field moves particles relative to the liquid, which generates ultrasound.
Electric sonic amplitude was experimentally discovered by Oja and co-authors in the early 1980s. It is also widely used for characterizing zeta potential in dispersions and emulsions. There is review of the theory of this effect, its experimental verification, and multiple applications published by Hunter.
See also
Interface and colloid science
Zeta potential
References
Chemical mixtures
Colloidal chemistry | Electric sonic amplitude | [
"Chemistry"
] | 147 | [
"Colloidal chemistry",
"Colloids",
"Surface science",
"Chemical mixtures",
"nan"
] |
13,680,140 | https://en.wikipedia.org/wiki/Diphenylphosphoryl%20azide | Diphenylphosphoryl azide (DPPA) is an organic compound. It is widely used as a reagent in the synthesis of other organic compounds.
Uses
DPPA undergoes pseudohalogen replacement of the azido group by treatment with nucleophilic reagents, such as ammonia and various amines.
This compound is used as a reagent for the synthesis of peptides by virtue of its reactions with carboxylic acids leading to either the urethane or the amide. The formation of the urethane is particularly valuable since it works with carboxylic acids which fail to undergo the Schmidt reaction, and is believed to involve transfer of the azido group to the carboxylic acid.
It is now suggested that this reaction proceeds through the intermediate mixed anhydride, resulting from attack by the nucleophilic carboxylate anion on the phosphorus atom, with expulsion of the azide ion. The latter then attacks the carbonyl carbon atom, to give the acyl azide and loss of the diphenylphosphate anion, known to be a good leaving group. Finally, the acyl azide reacts in the normal manner to give the urethane.
Studies show that DPPA reacts with amines giving the corresponding phosphoramidates; it therefore appears that formation of the amide similarly involves the intermediate anhydride, followed by nucleophilic substitution by the amine.
In the synthesis of NSAIDs, DPPA is able to rearrange a propanoyl group into an isopropanoic acid.
DPPA is also used to prepare an acyl azide for use in the Curtius reaction.
Safety
DPPA is very toxic and a potential explosive like most other azide compounds.
See also
Tosyl azide
Trifluoromethanesulfonyl azide
References
Organophosphoropseudohalidates
Azido compounds
Reagents for organic chemistry
Phenol esters
Phenyl compounds
Phosphorus-nitrogen compounds | Diphenylphosphoryl azide | [
"Chemistry"
] | 425 | [
"Reagents for organic chemistry"
] |
13,680,174 | https://en.wikipedia.org/wiki/Lake%20of%20fire | The lake of fire is a concept that appears in both the ancient Egyptian and Christian religions. In ancient Egypt, it appears as an obstacle on the journey through the underworld which can destroy or refresh the deceased. In Christianity, it is as a place of after-death punishment of the wicked. The phrase is used in five verses of the Book of Revelation. In the biblical context, the concept seems analogous to the Jewish Gehenna, or the more common concept of Hell. The image of the lake of fire was taken up by the early Christian Hippolytus of Rome in about the year 230 and has continued to be used by modern Christians.
Ancient Egyptian religion
Fiery rivers and lakes in the underworld are mentioned in works such as the Coffin Texts and the Egyptian Book of the Dead. Around their edges sit flaming braziers or baboons. Ra would pass through this lake on his journey through the Duat, renewing his boat. Chapter 126 of the Egyptian Book of the Dead is associated with this vignette and the text is addressed to the "four baboons who sit in the prow of the Barque of Re." The lake was one of the dangers encountered on the journey through the Duat and had a dual nature. The baboons who guarded the pool were a force that could refresh and protect the deceased if they knew the correct recitation or destroy them if they did not. In the 21st Dynasty, human figures are depicted within the lakes. These represent enemies of the king or gods and their inclusion within the pools ensures their permanent destruction. In this way, the deceased could avoid meeting a similar fate, and be victorious over the forces of chaos like Ra. Am-heh, whose name means "devourer of millions" or "eater of eternity", is a hunting dog headed god from the underworld who lived in a lake of fire.
Christianity
Mark 9:43 has Jesus himself use the image of a punishing unquenchable fire:
Book of Revelation
The Book of Revelation has five verses that mention a "lake of fire" ():
A commonly accepted and traditional interpretation is that the "lake of fire" and the "second death" are symbolic of eternal pain, pain of loss and perhaps pain of the senses, as punishment for wickedness. The Greek words translated "torment" or "tormented" in English come from the root with the original meaning of "the testing of gold and silver as a medium of exchange by the proving stone" and a later connotation of a person, especially a slave, "severely tested by torture" to reveal truth. It can also have a connotation of torment or extreme suffering.
Denominational views
Anabaptism
Anabaptist Christians distinguish between the intermediate state that one enters after death, and the final state after the Last Judgment:
Restorationism
Jehovah's Witnesses interpret the "lake of fire" and "second death" of the Book of Revelation as referring to a complete and definitive annihilation of those cast into it.
Seventh-day Adventists believe in annihilation as well. They too believe that the lake of fire passage is referring to extinction, not to an eternal place of torment as understood in the mainstream Protestant interpretation.
Members of the Church of Jesus Christ of Latter-day Saints and other churches within the Latter Day Saint Movement read of a concept of the "lake of fire" in the Book of Mormon, in several passages. The most descriptive instance of a "lake of fire" in the Book of Mormon occurs in Jacob 6:10, which reads, "Ye must go away into that lake of fire and brimstone, whose flames are unquenchable, and whose smoke ascendeth up forever and ever, which lake of fire and brimstone is endless torment." The Book of Mormon also refers to the lake of fire as a state of second death or spiritual death, where there is no hope for redemption or salvation until after the resurrection or, for sons of perdition, never.
Third century
Hippolytus of Rome ( 235) pictured Hades, the abode of the dead, as containing "a lake of unquenchable fire" at the edge of which the unrighteous "shudder in horror at the expectation of the future judgment, (as if they were) already feeling the power of their punishment". The lake of fire is described by Hippolytus unambiguously as the place of eternal torment for the sinners after the resurrection.
20th-century views
The Catholic Portuguese visionary Lúcia Santos reported that the Virgin Mary (Our Lady of Fatima) had given her a vision of Hell as a sea of fire:
Universalist eschatology
Early Christian Universalists, most notably Origen of Alexandria (), and Gregory of Nyssa (), understood the lake of fire as a symbolic purifying fire used to eliminate the dross from the gold, or a "refiner's crucible". Origen refers to the "lead of wickedness" that must be refined out of the gold. Origen obtained his Universalist views, known then as apocatastasis, from his mentor Clement of Alexandria (), who was a student of Pantaenus. Origen explained the refining metaphor in response to a philosopher named Celsus who accused Christians of representing God as a merciless tormentor armed with fire.
In the view of Origen:
19th-century scholar Charles Bigg summarized Origen's view as, "Slowly yet certainly the blessed change must come, the purifying fire must eat up the dross and leave the pure gold. One by one we shall enter into rest, never to stray again. Then when death, the last enemy, is destroyed, when the tale of his children is complete, Christ will 'drink wine in the kingdom of his Father.' This is the end, when 'all shall be one, as Christ and the Father are one,' when 'God shall be all in all.'"
In the view of Gregory of Nyssa, "when death approaches to life, and darkness to light, and the corruptible to the incorruptible, the inferior is done away with and reduced to non-existence, and the thing purged is benefited, just as the dross is purged from gold by fire."
Further evidence corroborating their interpretation of the lake of fire as a "refiner's crucible" is that the Greek word commonly translated as "lake" also refers to something small, like a pond or a "pool", as translated in the Wycliffe and New American Bible (NABRE).
See also
Ammit
Hell
Eternal life (Christianity)
Inferno (disambiguation)
Lake of Fire (song)
Lake of Fire (film)
Purgatory
Notes
References
External links
Geoffrey W. Bromiley (ed.), The International Standard Bible Encyclopedia:K–P (Wm. B. Eerdmans Publishing 1995 ), p. 61, s.v. "Lake of fire"
Geoffrey W. Bromiley (ed.), The International Standard Bible Encyclopedia:Q–Z (Wm. B. Eerdmans Publishing 1995 ), p. 947, s.v. "Unquenchable fire"
Afterlife in Christianity
Biblical phrases
Book of Revelation
Christian terminology
Fire in religion
Hell (Christianity)
The Beast (Revelation)
Lakes
Locations in Egyptian mythology
Punishments in religion | Lake of fire | [
"Environmental_science"
] | 1,522 | [
"Lakes",
"Hydrology"
] |
13,680,395 | https://en.wikipedia.org/wiki/Named%20entity | In information extraction, a named entity is a real-world object, such as a person, location, organization, product, etc., that can be denoted with a proper name. It can be abstract or have a physical existence. Examples of named entities include Barack Obama, New York City, Volkswagen Golf, or anything else that can be named. Named entities can simply be viewed as entity instances (e.g., New York City is an instance of a city).
From a historical perspective, the term Named Entity was coined during the MUC-6 evaluation campaign and contained ENAMEX (entity name expressions e.g. persons, locations and organizations) and NUMEX (numerical expression).
A more formal definition can be derived from the rigid designator by Saul Kripke. In the expression "Named Entity", the word "Named" aims to restrict the possible set of entities to only those for which one or many rigid designators stands for the referent. A designator is rigid when it designates the same thing in every possible world. On the contrary, flaccid designators may designate different things in different possible worlds.
As an example, consider the sentence, "Biden is the president of the United States". Both "Biden" and the "United States" are named entities since they refer to specific objects (Joe Biden and United States). However, "president" is not a named entity since it can be used to refer to many different objects in different worlds (in different presidential periods referring to different persons, or even in different countries or organizations referring to different people). Rigid designators usually include proper names as well as certain natural terms like biological species and substances.
There is also a general agreement in the Named Entity Recognition community to consider temporal and numerical expressions as named entities, such as amounts of money and other types of units, which may violate the rigid designator perspective.
The task of recognizing named entities in text is Named Entity Recognition while the task of determining the identity of the named entities mentioned in text is called Named Entity Disambiguation. Both tasks require dedicated algorithms and resources to be addressed.
See also
Named-entity recognition (also referred to as entity identification, entity chunking and entity extraction)
Entity linking (also referred to as named entity linking (NEL), named entity disambiguation (NED), named entity recognition and disambiguation (NERD) or named entity normalization)
Information extraction
Knowledge extraction
Text mining (also referred to as text data mining)
Truecasing
Apache OpenNLP
spaCy
General Architecture for Text Engineering
Natural Language Toolkit
References
zh-yue:有名實體
Natural language processing
Computational linguistics | Named entity | [
"Technology"
] | 555 | [
"Natural language processing",
"Natural language and computing",
"Computational linguistics"
] |
13,680,406 | https://en.wikipedia.org/wiki/Ion%20vibration%20current | The ion vibration current (IVI) and the associated ion vibration potential is an electric signal that arises when an acoustic wave propagates through a homogeneous fluid.
Historically, the IVI was the first known electroacoustic phenomenon. It was predicted by Peter Debye in 1933.
When a longitudinal sound wave travels through a solvent, the associated pressure gradients push the fluid particles back and forth, and it is easy in practice to create such accelerations that measure thousands or millions of g's. If a solute molecule is more dense or less dense than the surrounding liquid, then in this accelerating environment, the molecule will move relative to the surrounding liquid. This relative motion is essentially the same phenomenon that occurs in a centrifuge, or more simply, it is essentially the same phenomenon that occurs when low-density objects float to the top of a glass of water, and high-density particles sink to the bottom (see the equivalence principle, which states that gravity is just like any other acceleration). The amount of relative motion depends on the balance between the molecule's effective mass (which includes both the mass of the molecule itself and any solvent molecules that are so tightly bound to the molecule that they follow along with the molecule's motion), its effective volume (related to buoyant force), and the viscous drag (friction) between the molecule and the surrounding fluid.
IVI concerns the case where the particles in question are anions and cations. In general, they will have different amounts of motion relative to the fluid during the sound wave oscillations, and that discrepancy creates an alternating electric potential between various points in a sound wave.
This effect was extensively used in the 1950s and 1960s for characterizing ion solvation. These works are mostly associated with the names of Zana and Yaeger, who published a review of their studies in 1982.
This effect can be studied with modern devices that employ electroacoustics for studying zeta potential, as described in the book.
See also
Interface and colloid science
References
Chemical mixtures
Colloidal chemistry
Soft matter | Ion vibration current | [
"Physics",
"Chemistry",
"Materials_science"
] | 428 | [
"Colloidal chemistry",
"Soft matter",
"Colloids",
"Surface science",
"Chemical mixtures",
"Condensed matter physics",
"nan"
] |
13,680,444 | https://en.wikipedia.org/wiki/Streaming%20vibration%20current | The streaming vibration current (SVI) and the associated streaming vibration potential is an electric signal that arises when an acoustic wave propagates through a porous body in which the pores are filled with fluid.
Streaming vibration current was experimentally observed in 1948 by M. Williams. A theoretical model was developed some 30 years later by Dukhin and coworkers. This effect opens another possibility for characterizing the electric properties of the surfaces in porous bodies.
See also
Interface and colloid science
References
Chemical mixtures
Colloidal chemistry
Soft matter | Streaming vibration current | [
"Physics",
"Chemistry",
"Materials_science"
] | 112 | [
"Colloidal chemistry",
"Soft matter",
"Colloids",
"Surface science",
"Chemical mixtures",
"Condensed matter physics",
"nan"
] |
13,680,698 | https://en.wikipedia.org/wiki/Mass%20attenuation%20coefficient | The mass attenuation coefficient, or mass narrow beam attenuation coefficient of a material is the attenuation coefficient normalized by the density of the material; that is, the attenuation per unit mass (rather than per unit of distance). Thus, it characterizes how easily a mass of material can be penetrated by a beam of light, sound, particles, or other energy or matter. In addition to visible light, mass attenuation coefficients can be defined for other electromagnetic radiation (such as X-rays), sound, or any other beam that can be attenuated. The SI unit of mass attenuation coefficient is the square metre per kilogram (). Other common units include cm2/g (the most common unit for X-ray mass attenuation coefficients) and L⋅g−1⋅cm−1 (sometimes used in solution chemistry). Mass extinction coefficient is an old term for this quantity.
The mass attenuation coefficient can be thought of as a variant of absorption cross section where the effective area is defined per unit mass instead of per particle.
Mathematical definitions
Mass attenuation coefficient is defined as
where
μ is the attenuation coefficient (linear attenuation coefficient);
ρm is the mass density.
When using the mass attenuation coefficient, the Beer–Lambert law is written in alternative form as
where
is the area density known also as mass thickness, and is the length, over which the attenuation takes place.
Mass absorption and scattering coefficients
When a narrow (collimated) beam passes through a volume, the beam will lose intensity to two processes: absorption and scattering.
Mass absorption coefficient, and mass scattering coefficient are defined as
where
μa is the absorption coefficient;
μs is the scattering coefficient.
In solutions
In chemistry, mass attenuation coefficients are often used for a chemical species dissolved in a solution. In that case, the mass attenuation coefficient is defined by the same equation, except that the "density" is the density of only that one chemical species, and the "attenuation" is the attenuation due to only that one chemical species. The actual attenuation coefficient is computed by
where each term in the sum is the mass attenuation coefficient and density of a different component of the solution (the solvent must also be included). This is a convenient concept because the mass attenuation coefficient of a species is approximately independent of its concentration (as long as certain assumptions are fulfilled).
A closely related concept is molar absorptivity. They are quantitatively related by
(mass attenuation coefficient) × (molar mass) = (molar absorptivity).
X-rays
Tables of photon mass attenuation coefficients are essential in radiological physics, radiography (for medical and security purposes), dosimetry, diffraction, interferometry, crystallography, and other branches of physics. The photons can be in form of X-rays, gamma rays, and bremsstrahlung.
The values of mass attenuation coefficients, based on proper values of photon cross section, are dependent upon the absorption and scattering of the incident radiation caused by several different mechanisms such as
Rayleigh scattering (coherent scattering);
Compton scattering (incoherent scattering);
photoelectric absorption;
pair production, electron-positron production in the fields of the nucleus and atomic electrons.
The actual values have been thoroughly examined and are available to the general public through three databases run by National Institute of Standards and Technology (NIST):
XAAMDI database;
XCOM database;
FFAST database.
Calculating the composition of a solution
If several known chemicals are dissolved in a single solution, the concentrations of each can be calculated using a light absorption analysis. First, the mass attenuation coefficients of each individual solute or solvent, ideally across a broad spectrum of wavelengths, must be measured or looked up. Second, the attenuation coefficient of the actual solution must be measured. Finally, using the formula
the spectrum can be fitted using ρ1, ρ2, … as adjustable parameters, since μ and each are functions of wavelength. If there are N solutes or solvents, this procedure requires at least N measured wavelengths to create a solvable system of simultaneous equations, although using more wavelengths gives more reliable data.
See also
Absorption coefficient
Absorption cross section
Attenuation length
Attenuation
Beer–Lambert law
Cargo scanning
Compton edge
Compton scattering
Cross section
High-energy X-rays
Mean free path
Molar attenuation coefficient
Propagation constant
Radiation length
Scattering theory
Transmittance
References
Physical quantities
Radiometry
Mass-specific quantities | Mass attenuation coefficient | [
"Physics",
"Mathematics",
"Engineering"
] | 945 | [
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"Telecommunications engineering",
"Physical quantities",
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"Mass",
"Intensive quantities",
"Mass-specific quantities",
"Physical properties",
"Matter",
"Radiometry"
] |
13,681,867 | https://en.wikipedia.org/wiki/Indoxacarb | Indoxacarb is an oxadiazine pesticide developed by DuPont that acts against lepidopteran larvae. It is marketed under the names Indoxacarb Technical Insecticide, Steward Insecticide and Avaunt Insecticide. It is also used as the active ingredient in the Syngenta line of commercial pesticides: Advion and Arilon.
Its main mode of action is via blocking of neuronal sodium channels, belonging to IRAC group 22A. It is fairly lipophilic with a Kow of 4.65. This pesticide should be used with caution since some insects such as the oriental tobacco budworm (Helicoverpa assulta) become resistant when exposed.
In 2021, the European Union chose not to renew Indoxacarb for use as a plant-protection insecticide. The United Kingdom still allows use of the compound until 2025.
Development
Indoxacarb was developed by the McCann et al. team at E. I. du Pont de Nemours.
Household products
Indoxacarb is the active ingredient in a number of household insecticides, including cockroach and ant baits, and can remain active after digestion.
In 2012 DuPont's Professional Products including the line of Advion and Arilon products was purchased by Syngenta.
Indoxacarb is the active ingredient in the pet product, Activyl, from Merck Animal Health. It is marketed to kill fleas on dogs and cats.
Toxicity to humans
While toxicity to humans has not been formally studied, there is a reported case of a person consuming indoxacarb in a suicide attempt. The patient developed methemoglobinemia following ingestion. Methemoglobinemia (also known as blue baby syndrome) is a condition which ultimately decreases the effectiveness of red blood cells to exchange oxygen with organs. Methemoglobinemia can be fatal if left untreated, however when the cause is exposure to a chemical agent (not genetic) a variety of treatments are available and effective.
References
Further reading
Moncada, Adriana. Environmental Fate of Indoxacarb. Environmental Monitoring Branch, Department of Pesticide Regulation, State of California. March 6, 2003
External links
DuPont Steward insecticide - FAQs. Updated 20 January 2007. Retrieved 2012-11-11
Pesticides
Ureas
Methyl esters
Trifluoromethyl ethers
Carboxylate esters
Carbamates
Nitrogen heterocycles
Oxygen heterocycles
Sodium channel blockers | Indoxacarb | [
"Chemistry",
"Biology",
"Environmental_science"
] | 515 | [
"Pesticides",
"Toxicology",
"Organic compounds",
"Biocides",
"Ureas"
] |
13,682,267 | https://en.wikipedia.org/wiki/Mobile-to-mobile%20convergence | The term mobile to mobile calling is used in many mobile phone plans to refer to making calls to other mobile phones using the same provider's network--which is often cheaper than other calls.
Mobile to mobile convergence (MMC) is a term to describe a technology used in modern computing and telephony. The term is an offshoot of fixed mobile convergence (FMC) and uses dual mode (cellular network and WiFi) phones with a special software client and an application server to connect voice calls and business applications via a VoWLAN or through cellular service.
Mobile-to-mobile convergence differs from conventional FMC in that the technology uses the WLAN to route calls via the internet as a primary function, and uses the wireless carrier network if the WLAN is not present as a secondary function. It is significant since it is viewed as a means to compete with carrier companies since the calls are routed around the cellular network. This is viewed as a more efficient use of networking technology than standard FMC solutions that are available as well, since most of the latter use the carrier network as the primary means of communication and do not leverage the lower cost and controls of IP networks that are generally installed at most modern businesses. In theory, it also provides the capability of providing a greater voice coverage area than either carrier or WLAN technology alone since some areas do not have cellular service coverage and others do not have WiFi.
The first offering known in the market successfully deploying MMC is beCherry, which is delivered by Belgian company Mondial Telecom. They offer an MMC solution on Symbian, iOS and Android. Other smartphone OSs are also considered.
See also
Fixed-mobile convergence
Convergence (telecommunications)
Computer network
Mobile technology | Mobile-to-mobile convergence | [
"Technology"
] | 351 | [
"nan"
] |
13,683,591 | https://en.wikipedia.org/wiki/Phytochelatin | Phytochelatins are oligomers of glutathione, produced by the enzyme phytochelatin synthase. They are found in plants, fungi, nematodes and all groups of algae including cyanobacteria. Phytochelatins act as chelators, and are important for heavy metal detoxification. They are abbreviated PC2 through PC11.
A mutant Arabidopsis thaliana lacking phytochelatin synthase is very sensitive to cadmium, but it grows just as well as the wild-type plant at normal concentrations of zinc and copper, two essential metal ions, indicating that phytochelatin is only involved in resistance to metal poisoning.
Because phytochelatin synthase uses glutathione with a blocked thiol group in the synthesis of phytochelatin, the presence of heavy metal ions that bind to glutathione causes the enzyme to work faster. Therefore, the amount of phytochelatin increases when the cell needs more phytochelatin to survive in an environment with high concentrations of metal ions.
Phytochelatin binds to Pb ions leading to sequestration of Pb ions in plants and thus serves as an important component of the detoxification mechanism in plants. Phytochelatin seems to be transported into the vacuole of plants, so that the metal ions it carries are stored safely away from the proteins of the cytosol.
Related peptides
There are groups of other peptides with a similar structure to phytochelatin, but where the last amino acid is not glycine:
History
Phytochelatin was first discovered in 1981 in fission yeast, and was named cadystin. It was then found in higher plants in 1985 and was named phytochelatin. In 1989 the biosynthetic enzyme, phytochelatin synthase, was discovered.
See also
pp. 228–230
Dunaliella
References
External links
Strong induction of phytochelatin synthesis by zinc in marine green alga, Dunaliella tertiolecta.
Peptides
Chelating agents | Phytochelatin | [
"Chemistry"
] | 441 | [
"Biomolecules by chemical classification",
"Molecular biology",
"Chelating agents",
"Peptides",
"Process chemicals"
] |
13,683,619 | https://en.wikipedia.org/wiki/Conference%20on%20Human%20Factors%20in%20Computing%20Systems | The ACM Conference on Human Factors in Computing Systems (CHI) series of academic conferences is generally considered the most prestigious in the field of human–computer interaction and is one of the top-ranked conferences in computer science. It is hosted by ACM SIGCHI, the Special Interest Group on computer–human interaction. CHI has been held annually since 1982 and attracts thousands of international attendees.
History
The CHI conference series started with the Human Factors in Computer Systems conference in Gaithersburg, Maryland, US in 1982, organized by Bill Curtis and Ben Shneiderman. During this meeting the formation of the ACM Special Interest Group on Computer–Human Interaction (SIGCHI) was first publicly announced. ACM SIGCHI became the sponsor of the Conference on Human Factors in Computing Systems. The first CHI conference was held in Boston, Massachusetts, US, in 1983. The second conference took place in San Francisco, in 1985. Since then, CHI conferences have been held annually in spring each year. Until 1992 the conference was held in Canada or the US. In 1993 CHI moved to Europe for the first time and was held in Amsterdam, the Netherlands.
Over the years, CHI has grown in popularity. The 1982 meeting drew 907 attendees. CHI 90 attracted 2,314. Attendance has been fairly stable since then. After the early years CHI became highly selective. Since 1993 the acceptance rate for full papers was consistently below 30 percent. After 1992 the average acceptance rate was around 20 percent. The number of accepted full papers is slowly increasing and reached 157 accepted papers with an acceptance rate of 22 percent in 2008. CHI reached over 3,300 attendees in 2013 and 3,855 in 2019.
CHI 2020, which was originally planned to take place on April, was cancelled due to COVID-19, and CHI 2021 was held online as a virtual conference chaired by Yoshifumi Kitamura and Aaron Quigley. CHI 2021 “making waves, combining strengths” was originally scheduled to take place in Yokohama.
Tracks
The CHI conference consists of multiple tracks, including:
Academic papers and notes (short papers) on a variety of topics, such as (ubiquitous computing, visualization, usability and user experience design)
Posters and demonstrations
Workshops and courses hosted by domain experts
Invited panels on relevant topics
Case studies from industry practitioners
Past and upcoming CHI conferences
Past and future CHI conferences include:
Notes
References
External links
ACM SIGCHI website
Computer science conferences
Human–computer interaction
Association for Computing Machinery conferences | Conference on Human Factors in Computing Systems | [
"Technology",
"Engineering"
] | 502 | [
"Computer science conferences",
"Computer conference stubs",
"Computer science",
"Human–machine interaction",
"Computing stubs",
"Human–computer interaction"
] |
13,683,785 | https://en.wikipedia.org/wiki/Top-down%20proteomics | Top-down proteomics is a method of protein identification that either uses an ion trapping mass spectrometer to store an isolated protein ion for mass measurement and tandem mass spectrometry (MS/MS) analysis or other protein purification methods such as two-dimensional gel electrophoresis in conjunction with MS/MS. Top-down proteomics is capable of identifying and quantitating unique proteoforms through the analysis of intact proteins. The name is derived from the similar approach to DNA sequencing. During mass spectrometry intact proteins are typically ionized by electrospray ionization and trapped in a Fourier transform ion cyclotron resonance (Penning trap), quadrupole ion trap (Paul trap) or Orbitrap mass spectrometer. Fragmentation for tandem mass spectrometry is accomplished by electron-capture dissociation or electron-transfer dissociation. Effective fractionation is critical for sample handling before mass-spectrometry-based proteomics. Proteome analysis routinely involves digesting intact proteins followed by inferred protein identification using mass spectrometry (MS). Top-down MS (non-gel) proteomics interrogates protein structure through measurement of an intact mass followed by direct ion dissociation in the gas phase.
Advantages
The main advantages of the top-down approach include the ability to detect degradation products, protein isoforms, sequence variants, combinations of post-translational modifications as well as simplified processes for data normalization and quantitation.
Top-down proteomics, when accompanied with polyacrylamide gel electrophoresis, can help to complement the bottom-up proteomic approach. Top-down proteomic methods can assist in exposing large deviations from predictions and has been very successfully pursued by combining Gel Elution Liquid-based Fractionation Entrapment Electrophoresis fractionation, protein precipitation, and reverse phase HPLC with electrospray ionization and MS/MS.
Characterization of small proteins represents a significant challenge for bottom up proteomics due to the inability to generate sufficient tryptic peptides for analysis. Top-down proteomics allows for low mass protein detection, thus increasing the repertoire of proteins known. While Bottom-up proteomics integrates cleaved products from all proteoforms produced by a gene into a single peptide map of the full-length gene product to tabulate and quantify expressed proteins, a major strength of Top-down proteomics is that it enables researchers to quantitatively track one or more proteoforms from multiple samples and to excise these proteoforms for chemical analysis.
Disadvantages
In the recent past, the top down approach was relegated to analysis of individual proteins or simple mixtures, while complex mixtures and proteins were analyzed by more established methods such as Bottom-up proteomics. Additionally protein identification and proteoform characterization in the TDP (Top-down proteomics) approach can suffer from a dynamic range challenge where the same highly abundant species are repeatedly fragmented.
Although Top-down proteomics can be operated in relatively high output in order to successfully map proteome coverage at a large level, the rate of identifying new proteins after initial rounds reduces quite sharply.
Top-down proteomics interrogation can overcome problems for identifying individual proteins, but has not been achieved on a large scale due to a lack of intact protein fractionation methods that are integrated with tandem mass spectrometry.
Research and uses
Study One: Quantitation and Identification of Thousands of Human Proteoforms below 30 kDa
Researchers performed a study of human proteoforms below 30kDa, used primary IMR90 human fibroblasts containing a Ras function construct that were grown in medium.
Chose to use Top-Down Proteomics to characterize these proteoforms because it is currently the best method for intact proteins, as I discussed Bottom Up digests the protein and does not do a good job of providing a clear image of distinct intact proteoforms.
Top Down Proteomics is capable of identifying and quantitating unique proteoforms through the analysis of intact proteins. The Top-down quantitation yielded changes in abundance of 1038 cytoplasmic proteoforms.
Study Two: Combining high-throughput MALDI-TOF mass spectrometry and isoelectric focusing gel electrophoresis for virtual 2D gel-based proteomics
Researchers used top-down proteomics because could identify the exact proteoforms of intact proteins, rather than the bottom-up approach which gives fragment ions of peptides.
This study used Virtual 2D gel along with Mass Spectrometry in order to separate protein mixtures. MALDI is a computer software that generates the intact masses of the proteins at each isoelectric point. It started with an image of an IPG-IEF (isoelectric focusing) gel selection that was then analyzed by MALDI.
Top-down proteomics MALDI-TOF/TOF-MS is more tolerant to impurities; does not require biomarker extraction, purification, and separation; and can be directly applied to intact microorganisms.
See also
Protein mass spectrometry
Bottom-up proteomics
Shotgun proteomics
Tandem mass spectrometry (MS/MS)
References
Bibliography
Mass spectrometry
Proteomics | Top-down proteomics | [
"Physics",
"Chemistry"
] | 1,121 | [
"Spectrum (physical sciences)",
"Instrumental analysis",
"Mass",
"Mass spectrometry",
"Matter"
] |
13,683,986 | https://en.wikipedia.org/wiki/Alberta%20Royalty%20Review | The 2007 Alberta Royalty Review was an independent panel, chaired by William M. Hunter, established by the government of Alberta to review the level of resource royalties collected by the provincial government from petroleum and natural gas companies.
In their final report entitled "Our Fair Share" released on September 18, 2007, the panel concluded that Albertans, who own their natural resources, were not receiving their "fair share" from energy development. Royalty rates and formulas had "not kept pace with changes in the resource base and world energy markets." As a result of the review new regulations came into effect under the Alberta Mines and Minerals Act including the Petroleum Royalty Regulation, 2009, and the Natural Gas Royalty Regulation, 2009. The government of Alberta expected to collect approximately $2 billion annually with new royalty formulas implemented in 2009. Instead of an increase in royalties on oil and gas, Alberta collected $13.5 billion less from 2009 to 2014 with the new formula. There was a flaw in the 2009 New Well Royalty Rate formula which was in effect by May 1, 2011, regarding the royalties on gas which had provided almost 67% of total royalties collected by Alberta prior to 2009. Under the 2009 formula applied to Natural Gas and By-products represented a decrease from the previous fixed rates. With this formula gas royalties declined by approximately $5 billion per year and provided only 17% of total royalties. In 2008 the global price of oil plummeted from an all-time high of $145 a barrel on July 8, 2008, to $32 a barrel later in 2008 resulting in "the cancellation of many energy projects" in Alberta. By 2015 several of these oil projects had not resumed. In spite of this, Alberta collected $2 billion in oil sands royalties in the post-2009 period with the new rate of 20% compared to $1.5 billion from 2004 to 2009 with the old rate of 15%.
Average royalty rates
Background
In areas surveyed and homesteaded early in Alberta's history all sub-soil resource rights belong to the land owner, but in the areas surveyed later or in the massive crown land areas of the northern half of the province where the current productive oil fields are located, the Crown, represented by the provincial government, owns all sub-soil resources.
Unlike many other oil-producing jurisdictions such as Saudi Arabia or Norway, Alberta does not have a National Oil Company that owns and exploits all petroleum resources. Instead privately owned oil companies of various sizes, from inside and outside Canada are encouraged to drill for oil and gas or mine oil sands on Crown land, and in exchange pay a royalty.
In 1930, the Natural Resources Transfer Act, shifted control of natural resources in Alberta from the federal government to the provincial government.
Royalty rates
In 1931 the Alberta government set the royalty rate at five per cent on oil and gas, creating a rift with the oil industry.
In 1971, soon after winning a majority government for the Progressive Conservatives in 1971, then-premier Peter Lougheed moved to increase Alberta's share of royalties creating hostilities with the oil industry. At that time the price of oil was rising globally as the influence of the newly formed Organization of Petroleum Exporting Countries increased.
In 1986 when the price of oil bottomed at US$10 a barrel, Don Getty, who was premier from 1985 to 1992, responded by providing the oil industry with $250 million in incentives and royalty cuts. By the end of 1986 Alberta had granted another nine-month cut from 12% to 1% in royalties at the Suncor oilsands.
Ralph Klein lowered royalties during the early 1990s to spur investment in the oil sands that faced an uncertain future with the low price of oil at that time. In 1997 the Alberta government set a "generic royalty formula for oil sands projects" using the "1% and 25% formula." In 2001 the oil and gas industry represented 23 percent of Alberta's GDP.
In 2006, a year before becoming Premier of Alberta, Ed Stelmach announced his commitment to reviewing royalty rates for the oil sands as well as for conventional oil and natural gas. As Premier in 2007 he tasked then-Minister of Finance Lyle Oberg to lead the Alberta Royalty Review process. By 2007 The oil and gas industry represented 19 percent of the province's GDP.
In 2006-7 the oil sands royalty revenue was $2.411 billion. In 2007/08 it rose to $2.913 billion and it continued to rise in 2008/09 to $2.973 billion. Following the revised Alberta Royalty Regime it fell in 2009/10 to $1.008 billion. In that year Alberta's total resource revenue "fell below $7 billion...when the world economy was in the grip of recession."
In February 2012 the Province of Alberta "expected $13.4 billion in revenue from non-renewable resources in 2013–14. By January 2013 the province was anticipating only $7.4 billion. "30 per cent of Alberta's approximately $40-billion budget is funded through oil and gas revenues. Bitumen royalties represent about half of that total." In 2009/10 royalties from the oil sands amounted to $1.008 billion (Budget 2009 cited in Energy Alberta 2009.
In order to accelerate development of the oil sands, the federal and provincial governments more closely aligned taxation of the oil sands with other surface mining resulting in "charging one per cent of a project's gross revenues until the project's investment costs are paid in full at which point rates increased to 25 per cent of net revenue. These policy changes and higher oil prices after 2003 had the desired effect of accelerating the development of the oil sands industry. "A revised Alberta Royalty Regime was implemented on January 1, 2009 through which each oil sands project pays a gross revenue royalty rate of 1%.
The Oil and Gas Fiscal Regimes described how royalty payments were calculated:
When the price of oil per barrel is less than or equal to $55/bbl indexed against West Texas Intermediate (WTI) (Oil and Gas Fiscal Regimes 2011:30) (Indexed to the Canadian dollar price of WTI) to a maximum of 9%). When the price of oil per barrel is less than or equal to $120/ bbl indexed against WTI "payout."
Payout refers "the first time when the developer has recovered all the allowed costs of the project, including a return allowance on those costs equal to the Government of Canada long-term bond rate ["LTBR"].
In order to encourage growth and prosperity and due to the extremely high cost of exploration, research and development, oil sands and mining operations pay no corporate, federal, provincial taxes or government royalties other than personal income taxes as companies often remain in a loss position for tax and royalty purposes for many years. Defining a loss position becomes increasingly complex when vertically-integrated multi-national energy companies are involved. Suncor claims their realized losses were legitimate and that Canada Revenue Agency (CRA) is unfairly claiming "$1.2-billion" in taxes which is jeopardizing their operations.
"Bitumen Valuation Methodology (BVM) is a method to determine for royalty purposes a value for bitumen produced in oil sands projects and either upgraded on-site or sold or transferred to affiliates. The BVM ensures that Alberta receives market value for its bitumen production, taken in cash or bitumen royalty-in-kind, through the royalty formula. Western Canadian Select (WCS), a grade or blend of Alberta bitumens, diluents (a product such as naphtha or condensate which is added to increase the ability of the oil to flow through a pipeline) and conventional heavy oils, developed by Alberta producers and stored and valued at Hardisty, AB was determined to be the best reference crude price in the development of a BVM."
By the end of 2001 the price of oil was as low as $20 a barrel. By July 8, 2008 the price of oil steadily increased until it reached an all-time high of $145 a barrel. Later in 2008 the price of oil plummeted to $32 a barrel resulting in "the cancellation of many energy projects" in Alberta. By 2015 several of these oil projects had not resumed.
In 2009/2010 the Alberta government collected $6.1 billion in royalties representing a drop of $3 billion.
According to a 2015 University of Alberta's Parkland Institute report by Jim Roy, who was a senior advisor for Royalty Policy for Alberta Energy from 1985 to 1993, from 2010 to 2015 Alberta collected $13.5 billion less in royalty than in the previous five years. Instead of getting the expected $2 billion per year increase, Alberta saw a $3 billion per year decrease. The decrease was composed of a $5 billion per year decrease in gas royalty partially offset by increases in oil royalty and oil sands royalty. The total value of hydrocarbon production was about the same during each five-year period.
From October 2009 to 2013/14 bitumen and crude oil royalties "averaged $6.2 billion and contributed just under 16 per cent to government revenues on an annual basis." The Alberta government predicted in its 2014/15 fiscal-year budget that there would be "an annual average of $8.0 billion in bitumen and crude oil royalties over the next three fiscal years (2014/15 to 2016/17) and an increase in the annual share of bitumen and crude oil royalties to over 17 per cent of government revenues."
In 2012–2013 $3.56 billion in royalties were collected from the oil sands.
Global price of oil
Royalty rates on oil in Alberta are based on the price of West Texas Intermediate, the benchmark in oil pricing in North America and the underlying commodity of New York Mercantile Exchange's oil futures contracts. Western Canadian Select is the benchmark crude for Albertan oil.
Findings
In a letter addressed to the Alberta Finance Minister in September 2007, the Chairman of the 2007 Alberta Royalty Review Bill Hunter, claimed "Albertans do not receive their fair share from energy development and they have not, in fact, been receiving their fair share for some time."
The panel's report not only recommended increased royal rates for all three major resources (conventional oil, natural gas, and oilsands) but also insisted that the government had failed to collect royalties already owed.
The recommended rate increase amounted to a 20% increase or an extra $2 billion per year.
Response
Some supporters of the oil industry responded to the 2007 Review with concerns that Calgary would become the "Caracas on the Bow" in the province of "Albertastan."
In 2007 the political response was highly polarized, with the parties of the left, the Alberta Liberals and Alberta New Democrats, criticizing the government for failing to get Alberta's "fair share" and, in effect, subsidizing oil companies at the expense of the public purse. They failed to make any gains against the Conservatives during the Alberta provincial general election of 2008, however, despite a record low turnout caused primarily by traditional Tory supporters staying home.
The highly respected global energy consultancy Wood Mackenzie released a study in September 2007, in which they ranked Alberta's 2007 fiscal regime for oil sands as 11th most favourable out of 100 jurisdictions globally. If all of the recommendations of the report [were] implemented, the report indicated "that the oil sand terms would still rank 44 out of 100 countries in terms of attractiveness." In 2007 the proposed 64% government take remained well below the average government take of 74% calculated by Wood Mackenzie for the other countries in the study (this take included government equity participations in many countries). The Wood Mackenzie study confirms the findings of the Panel in this regard."
In September 2007, TD Bank Financial Group Chief economist, Don Drummond and Derek Burelton claimed Alberta's economy would continue to thrive. The TD report expected Alberta's response to the ARR to be "the next major event," TD economists suggested that many of the review Panel's recommendations made economic sense. TD Economics had designated the Calgary-Edmonton Corridor as Canada's western economic tiger in 2003. From 1993 to 2003, Calgary-Edmonton Corridor "registered explosive real economic growth and population increases, surpassing rates chalked up in the majority of North American urban centres." By 2003 oil and gas royalty revenues were surging and the Corridor was "the only urban region in Canada to rival U.S. metropolitan areas in terms of both productivity and standard of living."
Repercussions
The Conservatives partially implemented the panel's recommendations. This coincided with a fall in oil prices during the financial crisis of 2007–2008. Oil and gas companies, especially smaller companies, complained that this hurt their bottom line, and threatened to move out of the province or shut down. In 2008 the global price of oil plummeted from $145 /barrel to $32/barrel and many energy projects left the province or were shut down in Alberta. Some never resumed. Alberta collected $2 billion in oil sands royalties in the post-2009 period with the new rate of 20%.
The Alberta government announced on March 11, 2010, that royalty rates effective in January 2011, would be rolled back cutting the maximum rate for conventional oil from 50% to 40% of revenues and cutting the maximum rate for natural gas from 50% to 36%. The large decrease in royalty starting in 2009 was mostly due to the way the gas formula automatically adjusted to the falling price for natural gas. The government introduced a "new well" incentive that capped royalty to a maximum of 5% during the first year of production. However, this incentive had no actual effect on gas royalty because the price-sensitive formula has set a negative royalty rate each month since being introduced. For almost all wells, the royalty formula defaults to the minimum royalty rate of 5%. Those on the right criticized the government for raising royalties and damaging profits in Alberta's most important industry, which they likened the "killing The Goose That Laid the Golden Eggs". Junior oil companies were instrumental in funding the upstart Wildrose Party which emerged in the Alberta provincial general election of 2012 as the major challenger to the governing Tories, and became the Official Opposition.
The repercussion for royalties was that in 2009/2010, the Alberta government collected $6.1 billion in royalties for the oil and gas sector. This was a drop of $3 billion. Over the next five years, Alberta collected $13.5 billion less in royalty than in the previous five years. Instead of getting the expected $2 billion per year increase, Alberta saw a $3 billion per year decrease. The decrease was composed of a $5 billion per year decrease in gas royalty partially offset by increases in oil royalty and oil sands royalty. The total value of hydrocarbon production was about the same during each five-year period.
References
External links
Official website
CBC News Report
Politics of Alberta
Alberta, Royalty_Review
Royalty Review
Royalty Review
Energy in Alberta
Energy policy
Petroleum politics
Economy of Alberta
2007 in Canadian politics
2007 in Alberta | Alberta Royalty Review | [
"Chemistry",
"Environmental_science"
] | 3,048 | [
"Petroleum",
"Environmental social science",
"Petroleum politics",
"Energy policy"
] |
13,684,522 | https://en.wikipedia.org/wiki/Port%20Revel | The Port Revel Shiphandling Training Centre is a French maritime pilotage school that trains pilots, masters, and officers on large ships like supertankers, container ships, LNG carriers and cruise ships . The facility uses manned models at a 1:25 scale on a man-made lake designed to simulate natural conditions including harbours, canals, and open seas. It was the first such facility in the world. The Centre was created in 1967 near Grenoble, France, by Laboratoire Dauphinois d'Hydraulique (now Artelia).
The courses are given by former maritime pilots. Since 1967, the Centre has trained over 6 500 maritime pilots, captains and officers from all over the world. French, European, Australian, Brazilian and North American pilots make up 90% of the Centre's students.
The manned model training regime is now recommended by the International Maritime Organization under Resolution A 960 (23) of December 2005.
The facility was written about by John McPhee in an October, 1998 article for The Atlantic Monthly, later republished as Chapter Two in his book Uncommon Carriers (2006).
History
The centre's origin goes back to the fifties, when Port Revel's mother company, Sogreah, was studying bank erosion on the Suez Canal using model ships sailing on a scale model with a movable bed (i.e. granular material subjected to erosion by turbulent water movement).
At the end of the sixties this experience with free sailing model ships was used by Esso to anticipate the manoeuvring behaviour of the new, much larger, oil tankers.
After three years spent with Esso captains between 1967 and 1970, the Centre was taken over by Sogreah in 1970.
During the 1970s, most students were captains, while the first maritime pilots came to discover the centre.
In the 1990s, the first refresher courses were organised for pilots, who returned every 5 years. These courses are less directive and leave more room for customisation, which is a way of optimising port operations to increase port accessibility.
Manned model shiphandling training has improved over the years because:
the instructors have become more proficient in delivering the courses and in their ability to structure courses as required,
lake facilities have undergone changes, such as the creation of extensive shallow water areas with currents, and can mimic specific port scenarios,
all kinds of large ships are available and model electronics have become more sophisticated in order to reproduce real ship manoeuvring behaviour,
tugs have become a part of the courses since 2000, providing realistic capability for berthing/unberthing operations and escort work,
pod propulsion is available since 2006,
introducing quality assurance has increased the reliability of ships and equipment,
the lake area was extended from four to five hectares during the winter 2008-2009,
a large container ship (8 500 TEU) was added to the fleet in 2009,
a large LNG carrier of 266 000 m3, the Q-Max, was added in 2010,
a Controllable-pitch propeller (CPP) was introduced in 2013,
a cruise ship (5000 people) with 2 pods and powerful bow thrusters was added in 2014.
Manned models
Manned models are small scale models that can carry and be handled by at least one person on an open expanse of water. They must behave like real ships, giving the shiphandler the same sensations. Wind, currents, waves, water depths, channels and berths must be reproduced realistically.
Manned models are used for research (e.g. ship behaviour), engineering (e.g. port layout) and for training in shiphandling (e.g. maritime pilots, masters and officers). They are usually at 1:25 scale.
The aim of training on manned models is to enable seamen to acquire or to develop manoeuvring skills through a better understanding of a ship's behaviour as it sails in restricted water conditions at manoeuvring speed. Manned models are considered by ships' captains and maritime pilots as the next best thing to a full-scale prototype for understanding a ship's behaviour. Training on the scale models provides experience that could never be gained on real ships for the simple reason that neither ship-owners nor local authorities would allow such risks to be taken. Scale models allow the shiphandler to make mistakes. Scale models allow experimentation on ship behaviour to explore unknown fields beyond the limits of safety.
Periodic training on scale models will maintain shiphandling skills at their highest level and periodic evaluations will show it.
Those who have trained on both claim that scale models are complementary to computer simulators. While manoeuvres with currents, waves, tugs, anchors, bank effects, etc. are reproduced more accurately on scale models, numerical simulators are more realistic when it comes to the bridge environment.
In an ideal world, shiphandling training would consist of three things:
1. Training on board real ships: the environment is obviously realistic, but the time spent and the acceptable risks are limited.
2. Training on manned models: manoeuvres can be pushed beyond the safety limits and ships sail on real water, but there is limited reproduction of the captain's vision and of wind conditions.
3. Training on numerical simulators: the water and ships are simply equations, but the bridge and 360° vision are realistic enough to simulate Bridge Team Management and crisis management.
Lake
The 5 hectare lake is located in the lower Alps near Grenoble where the wind regime is very mild. Moreover, it is sheltered by a forest. Hence uncontrolled wind effects on ships are minimised.
At 1:25 scale, the lake area represents a navigable zone of about 5 by 2 nautical miles, allowing several models to sail at the same time at normal manoeuvring speeds and to berth at one of the 50 berths and piers. Shallow and very shallow water areas (less than 10% under keel-clearance for certain ships) are to be found on about 50% of the lake area.
The lake is fitted with wave, current and wind generators and complex port approach configurations. Around 40% of the lake is subjected to currents.
Fleet
The model ships are all at 1:25 scale. There are 11 ships and 4 tugs. All ships are equipped with indicators giving rudder angle, engine speed, ship speed, wind speed, etc. Most of the ships are equipped with bow and stern thrusters and anchors. Five ships are equipped with a DGPS tracking system. Training with special features like Becker rudder, Schilling rudder, CPP is available.
See similitude of ship models for details of the scaling factors involved.
References
IMPA, 2014 - IMPA on Pilotage - pp161–169
John Mc Phee, 2006 - Uncommon Carriers - pp43–65
Michel R. Denis, 2006 - Récits Insolites - p49 & p113
The Nautical Institute, 1997 - On Pilotage and Shiphandling - p37, p181, p260, p280, p305
External links
Port Revel website
AFCAN website
Marine-Marchande.net website
Education in France
Maritime colleges in France
Model boats
Scale modeling
Buildings and structures in Isère
Education in Auvergne-Rhône-Alpes | Port Revel | [
"Physics"
] | 1,481 | [
"Scale modeling"
] |
13,685,099 | https://en.wikipedia.org/wiki/Similitude%20of%20ship%20models |
Manned models
Many research workers, hydraulics specialists and engineers have used scale models for over a century, in particular in towing tanks. Manned models are small scale models that can carry and be handled by at least one person on an open expanse of water. They must behave just like real ships, giving the shiphandler the same sensations. Physical conditions such as wind, currents, waves, water depths, channels and berths must be reproduced realistically.
Manned models are used for research (e.g. ship behaviour), engineering (e.g. port layout) and for training in shiphandling (e.g. maritime pilots, masters and officers). They are usually at 1:25 scale.
Similitude of manned models
Worldwide, manned model schools have chosen to apply the similitude law of William Froude (1810-1879) for its manned models. This means that gravity is considered to be preponderant over the other forces acting on the hull (viscosity, capillarity, cavitation, compressibility, etc.).
The different aspects of similitude may thus be defined as follows:
Physical similitude
Similitude of shape: The model has exactly the same geometric shape as the real ship. This means that all the length (L) dimensions of the real ship are divided by the same factor, the scale factor. The designers of Port Revel chose a scale (S) of 1:25, so:
S(L) = 25 (smaller, hence distance is 25 times less)
In this similitude, the proportions are kept (the ratios between the various dimensions of the ship are identical). This is also the case with the block coefficient. Furthermore, the angles are a length ratio, so they are also identical to the original ones. The scale factors of the areas and volumes are deduced from this, i.e.:
S2(L) = 252 = 625
S3(L) = 253 = 15 625
Similitude of mass (M): The model used for shiphandling training must not only resemble the original but also move in the same way as the original when subjected to similar forces. Consequently, the scale factor for the mass (M) and displacement is the same as that for the volumes, i.e.:
S(M) = S3(L) = 253 = 15 625
Similitude of forces (F): If the external forces on the model are in similitude, like the shapes, masses and inertia, the model's movement will be in similitude. It can thus be shown that the forces (F) must be at the same scale as the masses and weights, so:
S(F) = S(M) = 253 = 15 625
Similitude of speed(V): In agreement with Froude's law, the velocity scale is the square root of the length scale, so:
S(V) = S1/2(L) = sqrt(25) = 5 (times slower than in real life)
Similitude of time (T): Time is a distance (L) over speed (V), so:
S(T) = S(L) / S(V) = S1/2(L) = sqrt(25) = 5 (times faster than in real life)
Similitude of power (P): As the power P = F x V, hence S(P) = S(F) x S(V), so:
S(P) = S3(L) x S1/2(L) = S7/2(L) = 257/2 = 78 125
In conclusion, by choosing a scale of 1:25 for the lengths and by complying with Froude's law, the engineers at Sogreah – Port Revel built models 25 times smaller, operating 5 times more slowly, but as the distances are 25 times less, things occur 5 times faster.
The ships are 78 125 times less powerful.
Similitude of manoeuvres
While the models must be in correct similitude, this is not enough. Other factors can affect the correct reproduction of the manoeuvres, such as the field of vision, on-board equipment and wind.
First, manoeuvres on a model require the same pilot's orders as those on a real ship. The only difference is that they are executed five times faster on the model, so there is no time to discuss them (in fact, the rate of operation is such that the captain and helmsman swap roles every hour to avoid fatigue). This encourages responses to become intuitive but based upon a pre-assessed but flexible plan. What is a crisis on Day 1 of a manned model course becomes routine by Days 3+ which has to be a good definition of training.
The captain's position gives him a true field of vision from the bridge. He gives his orders to the helmsman, who is seated in front of him and operates the wheel and engine.
Control panels show the usual information (engine speed, rudder angle, heading, log, wind speed and direction, shackles of chain lowered). This information is shown in real-life values to help the trainee forget as far as possible that he is on a scale model.
The ships are fitted with bow and stern thrusters and perfectly operational anchors. They behave like real ships from this point of view as well.
Tugs are under the captain's orders via remote control, and are handled by a real tug captain.
As far as the wind is concerned, it should be recalled that as the speed scale factor is 1 in 5, a wind of 10 knots on the lake is equivalent to a 50 knot squall in reality. Ripples on the surface of the water and the movement of leaves on the trees are therefore unreliable indicators. The wind and ship speeds displayed on the control panel are therefore very important for trainees. However, the lake is situated in a forest in a region with little wind, so that uncontrollable wind effects are minimised.
40 years' experience have shown that students quickly learn how to control the models just as they do the real ships that they are used to manoeuvring.
Manned model exercises promote good situational and spatial awareness, a lack of which contributes to most accidents and incidents.
Those who have trained on both claim that scale models are complementary to electronic simulators. While manoeuvres with currents, waves, tugs, anchors, bank effects, etc. are reproduced more accurately on scale models, numerical simulators are more realistic when it comes to the bridge environment.
References
External links
Port Revel website
AFCAN website
Marine-Marchande.net website
Model boats
Hydraulic engineering | Similitude of ship models | [
"Physics",
"Engineering",
"Environmental_science"
] | 1,395 | [
"Hydrology",
"Physical systems",
"Hydraulics",
"Civil engineering",
"Hydraulic engineering"
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13,685,265 | https://en.wikipedia.org/wiki/Logic%20Theorist | Logic Theorist is a computer program written in 1956 by Allen Newell, Herbert A. Simon, and Cliff Shaw. It was the first program deliberately engineered to perform automated reasoning, and has been described as "the first artificial intelligence program". Logic Theorist proved 38 of the first 52 theorems in chapter two of Whitehead and Bertrand Russell's Principia Mathematica, and found new and shorter proofs for some of them.
History
In 1955, when Newell and Simon began to work on the Logic Theorist, the field of artificial intelligence did not yet exist. Even the term itself ("artificial intelligence") would not be coined until the following summer.
Simon was a political scientist who had already produced classic work in the study of how bureaucracies function as well as developing his theory of bounded rationality (for which he would later win a Nobel Prize). The study of business organizations requires, like artificial intelligence, an insight into the nature of human problem solving and decision making. Simon remembers consulting at RAND Corporation in the early 1950s and seeing a printer typing out a map, using ordinary letters and punctuation as symbols. He realized that a machine that could manipulate symbols could just as well simulate decision making and possibly even the process of human thought.
The program that printed the map had been written by Newell, a RAND scientist studying logistics and organization theory. For Newell, the decisive moment was in 1954 when Oliver Selfridge came to RAND to describe his work on pattern matching. Watching the presentation, Newell suddenly understood how the interaction of simple, programmable units could accomplish complex behavior, including the intelligent behavior of human beings. "It all happened in one afternoon," he would later say. It was a rare moment of scientific epiphany.
"I had such a sense of clarity that this was a new path, and one I was going to go down. I haven't had that sensation very many times. I'm pretty skeptical, and so I don't normally go off on a toot, but I did on that one. Completely absorbed in it—without existing with the two or three levels consciousness so that you're working, and aware that you're working, and aware of the consequences and implications, the normal mode of thought. No. Completely absorbed for ten to twelve hours."
Newell and Simon began to talk about the possibility of teaching machines to think. Their first project was a program that could prove mathematical theorems like the ones used in Bertrand Russell and Alfred North Whitehead's Principia Mathematica. They enlisted the help of computer programmer Cliff Shaw, also from RAND, to develop the program. (Newell says "Cliff was the genuine computer scientist of the three".)
The first version was hand-simulated: they wrote the program onto 3x5 cards and, as Simon recalled:In January 1956, we assembled my wife and three children together with some graduate students. To each member of the group, we gave one of the cards, so that each one became, in effect, a component of the computer program ... Here was nature imitating art imitating nature.
They succeeded in showing that the program could successfully prove theorems as well as a talented mathematician. Eventually Shaw was able to run the program on the computer at RAND's Santa Monica facility.
In the summer of 1956, John McCarthy, Marvin Minsky, Claude Shannon and Nathan Rochester organized a conference on the subject of what they called "artificial intelligence" (a term coined by McCarthy for the occasion). Newell and Simon proudly presented the group with the Logic Theorist. It was met with a lukewarm reception. Pamela McCorduck writes "the evidence is that nobody save Newell and Simon themselves sensed the long-range significance of what they were doing." Simon confides that "we were probably fairly arrogant about it all" and adds:
They didn't want to hear from us, and we sure didn't want to hear from them: we had something to show them! ... In a way it was ironic because we already had done the first example of what they were after; and second, they didn't pay much attention to it.
Logic Theorist soon proved 38 of the first 52 theorems in chapter 2 of the Principia Mathematica. The proof of theorem 2.85 was actually more elegant than the proof produced laboriously by hand by Russell and Whitehead. Simon was able to show the new proof to Russell himself who "responded with delight". They attempted to publish the new proof in The Journal of Symbolic Logic, but it was rejected on the grounds that a new proof of an elementary mathematical theorem was not notable, apparently overlooking the fact that one of the authors was a computer program.
Newell and Simon formed a lasting partnership, founding one of the first AI laboratories at the Carnegie Institute of Technology and developing a series of influential artificial intelligence programs and ideas, including the General Problem Solver, Soar, and their unified theory of cognition.
Architecture
This is a brief presentation, based on.
The logical theorist is a program that performs logical processes on logical expressions.
Expressions
An expression is made of elements.
There are two kinds of memories: working and storage.
Each working memory contains a single element. The logical theorist usually uses 1 to 3 working memories.
Each storage memory is a list representing a full expression or a set of elements. In particular, it contains all the axioms and proven logical theorems.
An expression is an abstract syntax tree, each node being an element with up to 11 attributes.
For example, the logical expression is represented as a tree with a root element representing . Among the attributes of the root element are pointers to the two elements representing the subexpressions and .
Processes
There are four kinds of processes, from the lowest to the highest level.
instruction: These are similar to assembly code. They may either perform a primitive operation on an expression in working memory, or perform a conditional jump to another instruction. An example is "put the right sub-element of working-memory 1 to working-memory 2"
elementary process: These are similar to subroutines. A sequence of instructions that can be called.
method: A sequence of elementary processes. There are just 4 methods:
substitution: given an expression, it attempts to transform it to a proven theorem or axiom by substitutions of variables and logical connectives.
detachment: given expression , it attempts to find a proven theorem or axiom of form , where yields after substitution, then attempts to prove by substitution.
chaining forward: given expression , it attempts to find for a proven theorem or axiom of form , then attempt to prove by substitution.
chaining backward: given expression , it attempts to find for a proven theorem or axiom of form , then attempt to prove by substitution.
executive control method: This method applies each of the 4 methods in sequence to each theorem to be proved.
Logic Theorist's influence on AI
Logic Theorist introduced several concepts that would be central to AI research:
Reasoning as search Logic Theorist explored a search tree: the root was the initial hypothesis, each branch was a deduction based on the rules of logic. Somewhere in the tree was the goal: the proposition the program intended to prove. The pathway along the branches that led to the goal was a proof – a series of statements, each deduced using the rules of logic, that led from the hypothesis to the proposition to be proved.
Heuristics Newell and Simon realized that the search tree would grow exponentially and that they needed to "trim" some branches, using "rules of thumb" to determine which pathways were unlikely to lead to a solution. They called these ad hoc rules "heuristics", using a term introduced by George Pólya in his classic book on mathematical proof, How to Solve It. (Newell had taken courses from Pólya at Stanford). Heuristics would become an important area of research in artificial intelligence and remains an important method to overcome the intractable combinatorial explosion of exponentially growing searches.
List processing To implement Logic Theorist on a computer, the three researchers developed a programming language, IPL, which used the same form of symbolic list processing that would later form the basis of McCarthy's Lisp programming language, an important language still used by AI researchers.
Philosophical implications
Pamela McCorduck writes that the Logic Theorist was "proof positive that a machine could perform tasks heretofore considered intelligent, creative and uniquely human". And, as such, it represents a milestone in the development of artificial intelligence and our understanding of intelligence in general.
Simon told a graduate class in January 1956, "Over Christmas, Al Newell and I invented a thinking machine,"
and would write:
[We] invented a computer program capable of thinking non-numerically, and thereby solved the venerable mind-body problem, explaining how a system composed of matter can have the properties of mind.
This statement, that machines can have minds just as people do, would be later named "Strong AI" by philosopher John Searle. It remains a serious subject of debate up to the present day.
Pamela McCorduck also sees in the Logic Theorist the debut of a new theory of the mind, the information processing model (sometimes called computationalism or cognitivism). She writes that "this view would come to be central to their later work, and in their opinion, as central to understanding mind in the 20th century as Darwin's principle of natural selection had been to understanding biology in the nineteenth century." Newell and Simon would later formalize this proposal as the physical symbol systems hypothesis.
Notes
Citations
References
, pp. 44–46.
, pp. 161–170.
External links
Newell and Simon's RAND Corporation report on the Logic Theorist
Full length version of Newell and Simon's RAND Corporation report on the Logic Theorist
CMU Libraries: Human and Machine Minds
Source code as PDF on Github
History of artificial intelligence
Theorem proving software systems | Logic Theorist | [
"Mathematics"
] | 2,024 | [
"Theorem proving software systems",
"Automated theorem proving",
"Mathematical software"
] |
13,686,680 | https://en.wikipedia.org/wiki/Polypogon | Polypogon is a nearly cosmopolitan genus of plants in the grass family, commonly known beard grass or rabbitsfoot grass.
Description
Polypogon species vary in appearance; some are erect, while others drape over the ground in waves. Many have soft, fluffy inflorescences that look like rabbit's foot amulets.
Some are introduced species established outside their native ranges. Some of those are considered invasive species and noxious weeds, most notably Polypogon monspeliensis, the annual beard grass.
Species
Polypogon × adscendens Guss. - Italy
Polypogon australis Brongn. - Argentina, Chile incl Juan Fernández Islands
Polypogon chilensis (Kunth) Pilg. - Argentina, Chile incl Juan Fernández Islands, Paraguay, Uruguay, Peru, Brazil
Polypogon elongatus Kunth - USA (CA AZ CO TX), much of Mesoamerica + South America
Polypogon exasperatus (Trin.) Renvoize - Argentina, Chile, Paraguay, Uruguay, Peru, Ecuador, Bolivia, Colombia, southern Brazil
Polypogon fugax Nees ex Steud. - China, Japan, Korea, central + southwestern Asia, Ethiopia, Somalia
Polypogon griquensis (Stapf) Gibbs Russ. & Fish - Namibia, South Africa
Polypogon hissaricus (Roshev.) Bor - Xinjiang, Central Asia, Pakistan, Iran, Himalayas
Polypogon imberbis (Phil.) Johow - Argentina, Chile incl Juan Fernández Islands, Uruguay, southern Brazil
Polypogon interruptus Kunth - British Columbia, western United States (WA to CA + TX), Mexico, south America
Polypogon ivanovae Tzvelev - Xinjiang
Polypogon linearis Trin. - Chile
Polypogon maritimus Willd. - wetlands in Asia, Mediterranean
Polypogon mollis (Thouars) C.E.Hubb. & E.W.Groves - Tristan da Cunha
Polypogon monspeliensis (L.) Desf. - Africa, Eurasia; widely naturalized in North America
Polypogon nilgiricus Kabeer & V.J.Nair - India
Polypogon parvulus Roseng., B.R.Arrill. & Izag. - Uruguay, Argentina
Polypogon pygmeus Tzvelev - Afghanistan
Polypogon schimperianus (Hochst. ex Steud.) Cope - from Ethiopia + Saudi Arabia to Zimbabwe
Polypogon tenellus R.Br. - South Australia, Western Australia
Polypogon tenuis Brongn. - Ascension Island, St. Helena, Namibia, Cape Province
Polypogon viridis (Gouan) Breistr. - central + southwestern Asia, Mediterranean
Formerly included
Numerous species now regarded as better suited to other genera: Agrostis, Alopecurus, Brachypodium, Chaetium, Gymnopogon, Muhlenbergia, Pentameris, Reynaudia, and Triniochloa.
Phytoremediation
Polypogon monspeliensis was investigated for its mercury-accumulating properties as a phytoremediation plant. A U.S. NIS—National Institutes of Health-funded study showed the plant to take up 110 times more mercury (HgS) than control plant species. This mercury hyperaccumulator sequesters the toxin in its roots in an insoluble form, reducing exposure to ecological receptors in situ and in erosion sediments.
References
External links
Jepson Manual Treatment — Polypogon
USDA Plants Profile: Polypogon (rabbitsfoot grass)
Polypogon. Grass Manual on the Web.
Poaceae genera
Phytoremediation plants
Grasses of Africa
Grasses of Asia
Grasses of Europe
Grasses of North America
Grasses of Oceania
Grasses of South America | Polypogon | [
"Biology"
] | 800 | [
"Phytoremediation plants",
"Bioremediation"
] |
13,688,008 | https://en.wikipedia.org/wiki/Bottom-up%20proteomics | Bottom-up proteomics is a common method to identify proteins and characterize their amino acid sequences and post-translational modifications by proteolytic digestion of proteins prior to analysis by mass spectrometry.
The major alternative workflow used in proteomics is called top-down proteomics where intact proteins are purified prior to digestion and/or fragmentation either within the mass spectrometer or by 2D electrophoresis. Essentially, bottom-up proteomics is a relatively simple and reliable means of determining the protein make-up of a given sample of cells, tissues, etc.
In bottom-up proteomics, the crude protein extract is enzymatically digested, followed by one or more dimensions of separation of the peptides by liquid chromatography coupled to mass spectrometry, a technique known as shotgun proteomics. By comparing the masses of the proteolytic peptides or their tandem mass spectra with those predicted from a sequence database or annotated peptide spectral in a peptide spectral library, peptides can be identified and multiple peptide identifications assembled into a protein identification.
Advantages
For high throughput bottom-up methods, there is better front-end separation of peptides compared with proteins and higher sensitivity than the (non-gel) top-down methods.
Disadvantages
There is limited protein sequence coverage by identified peptides, loss of labile PTMs, and ambiguity of the origin for redundant
peptide sequences. Recently the combination of bottom-up and top-down proteomics, so called middle-down proteomics, is receiving a lot of attention as this approach not only can be applied to the analysis of large protein fragments but also avoids redundant peptide sequences.
See also
Protein mass spectrometry
Shotgun proteomics
Peptide mass fingerprinting
Top-down proteomics
References
Mass spectrometry
Proteomics | Bottom-up proteomics | [
"Physics",
"Chemistry",
"Biology"
] | 386 | [
"Spectrum (physical sciences)",
"Bioinformatics stubs",
"Instrumental analysis",
"Biotechnology stubs",
"Mass",
"Biochemistry stubs",
"Bioinformatics",
"Mass spectrometry",
"Matter"
] |
13,688,204 | https://en.wikipedia.org/wiki/EHP%20spectral%20sequence | In mathematics, the EHP spectral sequence is a spectral sequence used for inductively calculating the homotopy groups of spheres localized at some prime p. It is described in more detail in and . It is related to the EHP long exact sequence of ; the name "EHP" comes from the fact that George W. Whitehead named 3 of the maps of his sequence "E" (the first letter of the German word "Einhängung" meaning "suspension"), "H" (for Heinz Hopf, as this map is the second Hopf–James invariant), and "P" (related to Whitehead products).
For the spectral sequence uses some exact sequences associated to the fibration
,
where stands for a loop space and the (2) is localization of a topological space at the prime 2. This gives a spectral sequence with term equal to
and converging to (stable homotopy groups of spheres localized at 2). The spectral sequence has the advantage that the input is previously calculated homotopy groups. It was used by to calculate the first 31 stable homotopy groups of spheres.
For arbitrary primes one uses some fibrations found by :
where is the -skeleton of the loop space . (For , the space is the same as , so Toda's fibrations at are the same as the James fibrations.)
References
Spectral sequences | EHP spectral sequence | [
"Mathematics"
] | 287 | [
"Topology stubs",
"Topology"
] |
13,688,951 | https://en.wikipedia.org/wiki/Chlorine%20nitrate | Chlorine nitrate, with chemical formula ClONO2 is an important atmospheric gas present in the stratosphere. It is an important sink of reactive chlorine and nitrogen, and thus its formation and destruction play an important role in the depletion of ozone.
Chemical properties
It explosively reacts with metals, metal chlorides, alcohols, ethers, and most organic materials. When it is heated to decomposition, it emits toxic fumes of Cl2 and NOx.
Synthesis and reactions
It can be produced by the reaction of dichlorine monoxide and dinitrogen pentoxide at 0 °C:
Cl2O + N2O5 → 2 ClONO2
or by the reaction:
ClF + HNO3 → HF + ClONO2
It can also react with alkenes:
(CH3)2C=CH2 + ClONO2 → O2NOC(CH3)2CH2Cl
Chlorine nitrate reacts with metal chlorides:
4 ClONO2 + TiCl4 → Ti(NO3)4 + 4 Cl2
References
Inorganic chlorine compounds
Nitrates
Oxidizing agents
Chlorine(I) compounds
Hypochlorites | Chlorine nitrate | [
"Chemistry"
] | 247 | [
"Inorganic compounds",
"Redox",
"Nitrates",
"Oxidizing agents",
"Salts",
"Inorganic chlorine compounds"
] |
13,689,416 | https://en.wikipedia.org/wiki/Spoken%20dialog%20system | A spoken dialog system (SDS) is a computer system able to converse with a human with voice. It has two essential components that do not exist in a written text dialog system: a speech recognizer and a text-to-speech module (written text dialog systems usually use other input systems provided by an OS). It can be further distinguished from command and control speech systems that can respond to requests but do not attempt to maintain continuity over time.
Components
An automatic speech recognizer (ASR) decodes speech into text. Domain-specific recognizers can be configured for language designed for a given application. A "cloud" recognizer will be suitable for domains that do not depend on very specific vocabularies.
Natural language understanding transforms a recognition into a concept structure that can drive system behavior. Some approaches will combine recognition and understanding processing but are thought to be less flexible since interpretation has to be coded into the grammar.
The dialog manager controls turn-by-turn behavior. A simple dialog system may ask the user questions then act on the response. Such directed dialog systems use a tree-like structure for control; frame- (or form-) based systems allow for some user initiative and accommodate different styles of interaction. More sophisticated dialog managers incorporate mechanisms for dealing with misunderstandings and clarification.
The domain reasoner, or more simply the back-end, makes use of a knowledge base to retrieve information and helps formulate system responses. In simple systems, this may be a database which is queried using information collected through the dialog. The domain reasoner, together with the dialog manager, maintain the context of interaction and allows the system to reflect some human conversational abilities (for example using anaphora).
Response generation is similar to text-based natural language generation, but takes into account the needs of spoken communication. This might include the use of simpler grammatical constructions, managing the amount of information in any one output utterance and introducing prosodic markers to help the human participant absorb information more easily. A complete system design will also introduce elements of lexical entrainment, to encourage the human user to favor certain ways of speaking, which in turn can improve recognition performance.
Text-to-speech synthesis (TTS) realizes an intended utterance as speech. Depending on the application, TTS may be based on concatenation of pre-recorded material produced by voice professionals. In more complex applications TTS will use more flexible techniques that accommodate large vocabularies and that allow the developer control over the character ("personality") of the system.
Varieties of systems
Spoken dialog systems vary in their complexity. Directed dialog systems are very simple and require that the developer create a graph (typically a tree) that manages the task but may not correspond to the needs of the user. Information access systems, typically based on forms, allow users some flexibility (for example in the order in which retrieval constraints are specified, or in the use of optional constraints) but are limited in their capabilities. Problem-solving dialog systems may allow human users to engage in a number of different activities that may include information access, plan construction and possible execution of the latter.
Some examples of systems include:
Information access: Weather, trains schedules, stock quotes, directory assistance.
Transactional: credit card and bank enquiries; ticket purchases.
Maintenance: Technical support including documentation access and diagnostic testing.
Tutoring: For education, such as physics or math, and language learning.
Entertainment and chatting
History
Pionieers in dialogue systems are companies like AT&T (with its speech recognizer system in the Seventies) and CSELT laboratories, that led some European research projects during the Eighties (e.g. SUNDIAL) after the end of the DARPA project in the US.
References
The field of spoken dialog systems is quite large and includes research (featured at scientific conferences such as SIGdial and Interspeech) and a large industrial sector (with its own meetings such as SpeechTek and AVIOS).
The following might provide good technical introductions:
Michael F. McTear, Spoken Dialogue Technology
Gabriel Skantze, Error Handling in Spoken Dialogue Systems, 2007: chapter 2, Spoken dialogue systems.
Pirani, Giancarlo, ed. Advanced algorithms and architectures for speech understanding. Vol. 1. Springer Science & Business Media, 2013.
Speech recognition
Multimodal interaction
User interfaces
User interface techniques
Computational linguistics | Spoken dialog system | [
"Technology"
] | 906 | [
"User interfaces",
"Natural language and computing",
"Interfaces",
"Computational linguistics"
] |
13,689,691 | https://en.wikipedia.org/wiki/Whangaroa | Whangaroa, also known as Whangaroa Village to distinguish it from the larger area of the former Whangaroa County, is a settlement on Whangaroa Harbour in the Far North District of New Zealand. It is 8 km north-west of Kaeo and 35 km north-west of Kerikeri. The harbour is almost landlocked and is popular both as a fishing spot in its own right and as a base for deep-sea fishing.
History
The harbour was the scene of one of the most notorious incidents in early New Zealand history, the Boyd massacre. In December 1809 almost all the crew and 70 passengers were killed as utu (revenge) for the mistreatment of Te Ara, the son of a Ngāti Uru chief, who had been in the crew of the ship. Several days later the ship was burnt out after gunpowder was accidentally ignited. Relics of the Boyd are now in a local museum.
On 16 July 1824 on a voyage to Sydney from Tahiti, the crew and passengers of the colonial schooner Endeavour (Capt John Dibbs) stopped in Whangaroa Harbour. An altercation with the local Māori Ngāti Pou hapū (subtribe) of the Ngā Puhi iwi resulted in an incident where Maori warriors took control of the Endeavour and menaced the crew. The situation was defused by the timely arrival of the Ngāti Uru chief Te Ara, of Boyd fame.
In February 1827, the famous Ngā Puhi chief Hongi Hika was engaged in warfare against the tribes of Whangaroa. Acting contrary to the orders of Hongi Hika, some of his warriors plundered and burnt Wesleydale, the Wesleyan mission that had been established in June 1823 at Kaeo, nine kilometres from Whangaroa. The missionaries, Rev Turner and his wife and three children, together with Rev. Messrs, Hobbs and Stack, and Mr Wade and wife, were 'compelled to flee from Whangarooa (sic) for their lives'. They were conveyed by ship to Sydney, NSW. During a skirmish Hongi Hika was shot in the chest by one of his warriors. On 6 March 1828 Hongi Hika died at Whangaroa. There is no actual evidence that Hongi himself plundered the mission; he was busily pursuing the enemy and being wounded. Nor is there any direct evidence to implicate anybody else An alternate idea was put forward by William Williams of the CMS. " It appears beyond doubt, though our Wesleyan Friends are loath to believe it, that it was their own chief, Tepui, was the instigator of the whole business". The local Ngatiuru had made the land available to the mission. For years the missionaries had lived amongst them and grown prosperous while the tribe still ate fern root. There was no prospect of the missionaries moving on and no prospect of them becoming acceptable neighbours. They had not joined the tribe. They had set up their own tribe which was steadily wearing down the authority of the Ngatiuru leadership.
By the latter 19th century, the Whangaroa Harbour had become an important location for the kauri gum digging trade.
Demographics
Statistics New Zealand describes Whangaroa as a rural settlement. It covers and had an estimated population of as of with a population density of people per km2. Whangaroa is part of the larger Whakarara statistical area.
Whangaroa had a population of 141 in the 2023 New Zealand census, a decrease of 3 people (−2.1%) since the 2018 census, and an increase of 39 people (38.2%) since the 2013 census. There were 75 males and 66 females in 75 dwellings. The median age was 65.3 years (compared with 38.1 years nationally). There were 6 people (4.3%) aged under 15 years, 6 (4.3%) aged 15 to 29, 54 (38.3%) aged 30 to 64, and 72 (51.1%) aged 65 or older.
People could identify as more than one ethnicity. The results were 89.4% European (Pākehā); 10.6% Māori; 6.4% Pasifika; 2.1% Asian; 2.1% Middle Eastern, Latin American and African New Zealanders (MELAA); and 4.3% other, which includes people giving their ethnicity as "New Zealander". English was spoken by 97.9%, Māori language by 4.3%, and other languages by 8.5%. No language could be spoken by 2.1% (e.g. too young to talk). The percentage of people born overseas was 19.1, compared with 28.8% nationally.
Religious affiliations were 29.8% Christian, 2.1% Hindu, 2.1% Buddhist, and 2.1% other religions. People who answered that they had no religion were 57.4%, and 6.4% of people did not answer the census question.
Of those at least 15 years old, 24 (17.8%) people had a bachelor's or higher degree, 81 (60.0%) had a post-high school certificate or diploma, and 33 (24.4%) people exclusively held high school qualifications. The median income was $26,200, compared with $41,500 nationally. 9 people (6.7%) earned over $100,000 compared to 12.1% nationally. The employment status of those at least 15 was that 27 (20.0%) people were employed full-time, 15 (11.1%) were part-time, and 3 (2.2%) were unemployed.
References
Wises New Zealand Guide, 7th Edition, 1979. p. 508.
External links
Photographs of Whangaroa held in Auckland Libraries' heritage collections.
Far North District
Populated places in the Northland Region
Whaingaroa
Kauri gum | Whangaroa | [
"Physics"
] | 1,238 | [
"Amorphous solids",
"Unsolved problems in physics",
"Kauri gum"
] |
13,690,160 | https://en.wikipedia.org/wiki/Society%20for%20Developmental%20Biology | The Society for Developmental Biology (SDB), originally the Society for the Study of Development and Growth, is an organization for scientists and professionals around the world whose research is focused on the study of the developmental biology, embryology, and related disciplines.
History
The "Society for the Study of Development and Growth" (SDB) was founded in 1939. In August 1939, the SDB held its first conference, a symposium on Developmental and Growth, in a small village schoolhouse in North Truro, Massachusetts. In 1965, it was renamed the "Society for Developmental Biology" to reflect the SDB's advocacy of developmental biology.
Mission
The Society for Developmental Biology's mission is to employ, "... an inclusive philosophy to further the study of developmental biology and related disciplines; to foster, support, and provide a forum for all investigators in these fields; to educate non-specialists, educators, the general public, and policymakers about developmental biology and related disciplines; and to promote fair, respectful, ethical and equitable practices throughout the scientific enterprise."
Membership
SDB has more than 2,000 members and provides an international forum for research, education, and career development in developmental biology. Membership is open to all with discounted rates for students, postdoctoral researchers, and affiliates. SDB Emerging Research Organisms Grant supports the development of techniques, approaches, community resources, collaborations, and new lines of research to study developmental mechanisms in non-traditional systems.
Awards
SDB Career Awards recognize excellence in research, mentoring, education, and science communication in the developmental biology community.
Edwin Grant Conklin Medal recognizes extraordinary mentorship and research contributions to the field. The award was inaugurated in 1995 to honor the biologist Edwin Conklin.
Developmental Biology-SDB Lifetime Achievement Award, which began in 2000, recognizes outstanding and sustained contributions to the field through research, service to the scientific community, exceptional mentorship, and public advocacy.
Viktor Hamburger Outstanding Educator Prize recognizes innovative contributions to the teaching and learning of developmental biology and related fields.
Elizabeth D. Hay New Investigator Award recognizes a new investigator performing outstanding research in developmental biology.
SDB Trainee Science Communication Award recognizes great science communication and outreach efforts by the student and postdoctoral members.
SDB Academy, established in 2023, recognizes and celebrates the achievements of long-standing members who have made significant contributions to the Society’s overarching goals while positively engaging with the Society.
Professional and Career Development
SDB has made a concerted effort to diversify the pool of scientists by creating resources and professional development opportunities. In 2013, SDB created the Choose Development! Program—a two-summer immersion for undergraduate students belonging to underrepresented groups in STEM to join the research laboratory of an established SDB member. This research-intensive experience was enhanced by a multi-tier mentoring program for each student, recognition across Society, professional development activities, and networking opportunities at national conferences.
The Society began creating virtual career development programs geared toward early career scientists. Since 2020, SDB has developed the Ethel Browne Harvey Postdoctoral Seminar Series, Science Communication Internship, Get Into Grad School Webinar, Get Hired!, and New Faculty Boot Camp.
Publication
SDB publishes in a monthly peer reviewed journal, Developmental Biology.
References
External links
Society for Developmental Biology home page
Developmental Biology journal home page
Society for Developmental Biology records, 1940-2008, bulk 1963-1993 at the University of Maryland, Baltimore County
Developmental biology
Scientific societies based in the United States
Scientific organizations established in 1939 | Society for Developmental Biology | [
"Biology"
] | 704 | [
"Behavior",
"Developmental biology",
"Reproduction"
] |
13,690,253 | https://en.wikipedia.org/wiki/Cypenamine | Cypenamine (INN, BAN), or cypenamine hydrochloride (USAN), also known as 2-phenylcyclopentylamine, is a psychostimulant drug which was developed by a group at the William S. Merrell Chemical Company in the 1940s. It is currently known only in scientific research and has never been developed for market use. Cypenamine is currently legal throughout the entire world, and though its chemical structure has a vague similarity to certain controlled stimulants like fencamfamine, it is likely that it is too distant for it to be considered an illicit analogue under the United States Federal Analogue Act of the Controlled Substances Act.
Chemistry
Stereochemistry
2-Phenylcyclopentan-1-amine is a compound with two stereocenters. Thus, the following two enantiomeric pairs may exist:
(1RS,2SR)-trans-2-phenylcyclopentan-1-amine
(1RS,2RS)-cis-2-phenylcyclopentan-1-amine
The racemate (±)-trans-2-phenylcyclopentan-1-amine [1:1 mixture of (1R,2S)-trans-2-phenylcyclopentan-1-amine (box, left) and (1S,2R)-trans-2-phenylcyclopentan-1-amine (box, right)] is the active ingredient of cypenamine. Furthermore, the kinetic resolution of (±)-trans-2-phenylcyclopentan-1-amine by lipase B from Candida antarctica may be effectively performed by an aminolysis reaction.
Racemic cis-2-phenylcyclopentan-1-amine [1:1 mixture of (1R,2R)-cis-2-phenylcyclopentan-1-amine and (1S,2S)-cis-2-phenylcyclopentan-1-amine] has found no pharmacological application.
Homology
Cypenamine is a homolog of tranylcypromine, containing an expanded alicyclic ring that is two methylene units larger than the highly strained/reactive cyclopropane. The cyclohexane homologue has been reported, although the LD50s were all less than for plain amphetamine, it was still a functional stimulant.
See also
Amphetamine
Cyclopentamine
Methamphetamine
Propylhexedrine
References
Amines
Norepinephrine-dopamine releasing agents
Sympathomimetics
Stimulants | Cypenamine | [
"Chemistry"
] | 582 | [
"Amines",
"Bases (chemistry)",
"Functional groups"
] |
13,691,541 | https://en.wikipedia.org/wiki/Gilbertian%20mimicry | In evolutionary biology, Gilbertian mimicry is a rare type of mimicry in plants involving only two species, a host or prey animal which is the mimic, and its parasite or predator, which is both the model for the mimicry, and the dupe that is deceived by it. The mechanism provides a measure of protection for the mimic, as parasites and predators rarely attack their own species.
The first described example of Gilbertian mimicry is the mimicking of Heliconius butterfly eggs by the leaf stipules of Passiflora plants. These are thought to protect the plant as the butterfly avoids laying eggs near eggs already on a host plant, to give her own eggs the best chance of survival.
A later example is the mimicking of a mammalian hormone by an ant toxin which causes long-lasting hypersensitivity, Gilbertian mimicry at a molecular level.
Etymology
The name was coined by the French biologist as a phrase for the rare mimicry system. He named it after the American ecologist Lawrence E. Gilbert, who described the mechanism as a "coevolved mutualism" in 1975.
Mechanism
In Gilbertian mimicry, a potential host or prey drives away one of its parasites or predators by mimicking it, since few parasites or predators attack their own species. The mechanism can be seen as the reverse of predator-prey or parasite-host aggressive mimicry, where the wolf-in-sheep's-clothing attacker, disguised as its prey or host, is able to approach and attack undetected. Unlike in a conventional Batesian mimicry system, where the mimic, its model, and the dupe are of three different species, the parasite or predator in a Gilbertian system is both model and dupe. Only two species are thus involved, and the system is described as bipolar.
Passiflora stipules and Heliconius eggs
Gilbertian mimicry occurs in the plant genus Passiflora, which is grazed by the micropredator larvae of some Heliconius butterflies. The host plants have evolved small yellow projections on their leaves, stipules, that mimic mature Heliconius eggs near the point of hatching. Female butterflies avoid laying their eggs near eggs already on a plant, for two reasons. First, by choosing a plant without other Heliconius eggs, they reduce the amount of intraspecific competition between caterpillars. Second, the caterpillars are somewhat cannibalistic, so those females that lay on vacant leaves provide their offspring with a greater chance of not being eaten. Either way, an egg-free host plant offers the offspring the best chance of surviving to adulthood, and hence a selective advantage. The stipules thus appear to have evolved as Gilbertian mimics of butterfly eggs, under selection pressure from Heliconius.
Bull ant venom and epidermal growth factor
Another Gilbertian system involves Australian giant red bull ants, Myrmecia gulosa. These ants produce a venom which contains a substantial concentration of the toxic peptide named MIITX2-Mg1a. This mimics a vertebrate hormone, a peptide called epidermal growth factor. In a mammal's body, this powerfully activates an epidermal growth factor receptor named ErbB1. The result is long-lasting hypersensitivity in bitten mammals, implying that ErbB is involved in signalling mammalian pain. The mechanism is, according to David Eagles and colleagues, analogous to the Gilbertian Passiflora/Heliconius system, except that the mimicry exists at the level of molecules rather than whole organisms (butterfly eggs).
References
Mimicry | Gilbertian mimicry | [
"Biology"
] | 752 | [
"Mimicry",
"Biological defense mechanisms"
] |
5,707,206 | https://en.wikipedia.org/wiki/Ten%20Commandments%20of%20Computer%20Ethics | The Ten Commandments of Computer Ethics were created in 1992 by the Washington, D.C.–based Computer Ethics Institute. The commandments were introduced in the paper "In Pursuit of a 'Ten Commandments' for Computer Ethics" by Ramon C. Barquin as a means to create "a set of standards to guide and instruct people in the ethical use of computers." They follow the Internet Advisory Board's memo on ethics from 1987. The Ten Commandments of Computer Ethics copies the archaic style of the Ten Commandments from the King James Bible.
The commandments have been widely quoted in computer ethics literature but also have been criticized by both the hacker community and some in academia. For instance, Dr. Ben Fairweather of the Centre for Computing and Social Responsibility has described them as "simplistic" and overly restrictive.
ISC2, one of the thought leaders in the information security industry, has referred to the commandments in developing its own ethics rules.
The Ten Commandments of Computer Ethics
Thou shalt not use a computer to harm other people.
Thou shalt not interfere with other people's computer work.
Thou shalt not snoop around in other people's computer files.
Thou shalt not use a computer to steal.
Thou shalt not use a computer to bear false witness.
Thou shalt not copy or use proprietary software for which you have not paid (without permission).
Thou shalt not use other people's computer resources without authorization or proper compensation.
Thou shalt not appropriate other people's intellectual output.
Thou shalt think about the social consequences of the program you are writing or the system you are designing.
Thou shalt always use a computer in ways that ensure consideration and respect for other humans.
References
External links
The Ten Commandments of Computer Ethics listed at Computer Professionals for Social Responsibility
Centre for Computing and Social Responsibility
Computing and society
Ethics of science and technology
Professional ethics
Codes of conduct
1992 documents
Internet ethics
it:I dieci comandamenti dell'etica del computer | Ten Commandments of Computer Ethics | [
"Technology"
] | 409 | [
"Internet ethics",
"Computing and society",
"Ethics of science and technology"
] |
5,707,397 | https://en.wikipedia.org/wiki/LNW-80 | The LNW-80, released in 1982, is the first computer built by LNW Research Corporation (later known as LNW Computers). The computer is 100% compatible with the Tandy TRS-80 Model 1, but has some hardware enhancements. Most notable are the high-resolution color graphics, which could also be used for an 80×24 screen, with a special software driver (TRS-80 is 64×16, while 80×24 is the screen size most CP/M software needed). Other enhancements were high processor speed (Z-80A at 4 MHz), color support, and optionally, CP/M support. The LNW-80 was also sold as a kit.
The LNW supported four screen modes:
Mode 0 is the default TRS-80 screen with 64×16 characters, and 128×48 semigraphics.
Mode 1 is 480×192 monochrome.
Mode 2 uses high-resolution graphics memory to colorize the mode 0 graphics. This results in 128×48 dots with 8 colors per dot. This mode could be used to 'colorize' the standard TRS-80 games when loaded with special software.
Mode 3 uses low-res character memory to colorize the high-res pixels. This results in 384×192 pixels on 128×48 color fields. Per color field, a foreground and background color is selected from the basic eight colors. The colors are white, green, yellow, red, magenta, blue, blue-green and black.
LNW Research
LNW Research started by making third party extensions for the Tandy TRS-80 model 1 market. They started in 1979 or 1980 with a System Extension, a D.I.Y. kit replacement of the Tandy Expansion Interface. The LNW80 appeared at the end of 1980. Later came the LNDoubler, a high-quality double-density adapter in 1981. 1983 saw the LNW II, an upgrade of the LNW80 capable of running CP/M and the LNW Team, which included an Intel 8088 board for MS-DOS compatibility. The company folded due to bankruptcy in 1984.
References
External links
LNW80 Main Page, Galaxy of Features
Home computers
Z80-based home computers
TRS-80
Computer-related introductions in 1982 | LNW-80 | [
"Technology"
] | 489 | [
"Computing stubs",
"Computer hardware stubs"
] |
5,707,590 | https://en.wikipedia.org/wiki/%C3%89tale%20topology | In algebraic geometry, the étale topology is a Grothendieck topology on the category of schemes which has properties similar to the Euclidean topology, but unlike the Euclidean topology, it is also defined in positive characteristic. The étale topology was originally introduced by Alexander Grothendieck to define étale cohomology, and this is still the étale topology's most well-known use.
Definitions
For any scheme X, let Ét(X) be the category of all étale morphisms from a scheme to X. This is the analog of the category of open subsets of X (that is, the category whose objects are varieties and whose morphisms are open immersions). Its objects can be informally thought of as étale open subsets of X. The intersection of two objects corresponds to their fiber product over X. Ét(X) is a large category, meaning that its objects do not form a set.
An étale presheaf on X is a contravariant functor from Ét(X) to the category of sets. A presheaf F is called an étale sheaf if it satisfies the analog of the usual gluing condition for sheaves on topological spaces. That is, F is an étale sheaf if and only if the following condition is true. Suppose that is an object of Ét(X) and that is a jointly surjective family of étale morphisms over X. For each i, choose a section xi of F over Ui. The projection map , which is loosely speaking the inclusion of the intersection of Ui and Uj in Ui, induces a restriction map . If for all i and j the restrictions of xi and xj to are equal, then there must exist a unique section x of F over U which restricts to xi for all i.
Suppose that X is a Noetherian scheme. An abelian étale sheaf F on X is called finite locally constant if it is a representable functor which can be represented by an étale cover of X. It is called constructible if X can be covered by a finite family of subschemes on each of which the restriction of F is finite locally constant. It is called torsion if F(U) is a torsion group for all étale covers U of X. Finite locally constant sheaves are constructible, and constructible sheaves are torsion. Every torsion sheaf is a filtered inductive limit of constructible sheaves.
Grothendieck originally introduced the machinery of Grothendieck topologies and topoi to define the étale topology. In this language, the definition of the étale topology is succinct but abstract: It is the topology generated by the pretopology whose covering families are jointly surjective families of étale morphisms. The small étale site of X is the category O(Xét) whose objects are schemes U with a fixed étale morphism U → X. The morphisms are morphisms of schemes compatible with the fixed maps to X. The big étale site of X is the category Ét/X, that is, the category of schemes with a fixed map to X, considered with the étale topology.
The étale topology can be defined using slightly less data. First, notice that the étale topology is finer than the Zariski topology. Consequently, to define an étale cover of a scheme X, it suffices to first cover X by open affine subschemes, that is, to take a Zariski cover, and then to define an étale cover of an affine scheme. An étale cover of an affine scheme X can be defined as a jointly surjective family {uα : Xα → X} such that the set of all α is finite, each Xα is affine, and each uα is étale. Then an étale cover of X is a family {uα : Xα → X} which becomes an étale cover after base changing to any open affine subscheme of X.
Local rings
Let X be a scheme with its étale topology, and fix a point x of X. In the Zariski topology, the stalk of X at x is computed by taking a direct limit of the sections of the structure sheaf over all the Zariski open neighborhoods of x. In the étale topology, there are strictly more open neighborhoods of x, so the correct analog of the local ring at x is formed by taking the limit over a strictly larger family. The correct analog of the local ring at x for the étale topology turns out to be the strict henselization of the local ring . It is usually denoted .
Examples
For each étale morphism , let . Then is a presheaf on X; it is a sheaf since it can be represented by the scheme .
See also
Étale cohomology
Étale topos
Nisnevich topology
Smooth topology
ℓ-adic sheaf
References
J. S. Milne (2008). Lectures on Étale Cohomology
Algebraic geometry | Étale topology | [
"Mathematics"
] | 1,058 | [
"Mathematical structures",
"Sheaf theory",
"Topology",
"Category theory",
"Fields of abstract algebra",
"Algebraic geometry",
"Topos theory"
] |
5,707,633 | https://en.wikipedia.org/wiki/Splice%20site%20mutation | A splice site mutation is a genetic mutation that inserts, deletes or changes a number of nucleotides in the specific site at which splicing takes place during the processing of precursor messenger RNA into mature messenger RNA. Splice site consensus sequences that drive exon recognition are located at the very termini of introns. The deletion of the splicing site results in one or more introns remaining in mature mRNA and may lead to the production of abnormal proteins. When a splice site mutation occurs, the mRNA transcript possesses information from these introns that normally should not be included. Introns are supposed to be removed, while the exons are expressed.
The mutation must occur at the specific site at which intron splicing occurs: within non-coding sites in a gene, directly next to the location of the exon. The mutation can be an insertion, deletion, frameshift, etc. The splicing process itself is controlled by the given sequences, known as splice-donor and splice-acceptor sequences, which surround each exon. Mutations in these sequences may lead to retention of large segments of intronic DNA by the mRNA, or to entire exons being spliced out of the mRNA. These changes could result in production of a nonfunctional protein. An intron is separated from its exon by means of the splice site. Acceptor-site and donor-site relating to the splice sites signal to the spliceosome where the actual cut should be made. These donor sites, or recognition sites, are essential in the processing of mRNA. The average vertebrate gene consists of multiple small exons (average size, 137 nucleotides) separated by introns that are considerably larger.
Background
In 1993, Richard J. Roberts and Phillip Allen Sharp received the Nobel Prize in Physiology or Medicine for their discovery of "split genes". Using the model adenovirus in their research, they were able to discover splicing—the fact that pre-mRNA is processed into mRNA once introns were removed from the RNA segment. These two scientists discovered the existence of splice sites, thereby changing the face of genomics research. They also discovered that the splicing of the messenger RNA can occur in different ways, opening up the possibility for a mutation to occur.
Technology
Today, many different types of technologies exist in which splice sites can be located and analyzed for more information. The Human Splicing Finder is an online database stemming from the Human Genome Project data. The genome database identifies thousands of mutations related to medical and health fields, as well as providing critical research information regarding splice site mutations. The tool specifically searches for pre-mRNA splicing errors, the calculation of potential splice sites using complex algorithms, and correlation with several other online genomic databases, such as the Ensembl genome browser.
Role in Disease
Due to the sensitive location of splice sites, mutations in the acceptor or donor areas of splice sites can become detrimental to a human individual. In fact, many different types of diseases stem from anomalies within the splice sites.
Cancer
A study researching the role of splice site mutations in cancer supported that a splice site mutation was common in a set of women who were positive for breast and ovarian cancer. These women had the same mutation, according to the findings. An intronic single base-pair substitution destroys an acceptor site, thus activating a cryptic splice site, leading to a 59 base-pair insertion and chain termination. The four families with both breast and ovarian cancer had chain termination mutations in the N-terminal half of the protein. The mutation in this research example was located within the splice-site.
Splice-site mutations are recurrently found in key lymphoma genes like BCL7A or CD79B due to aberrant somatic hypermutation as the sequence targeted by AID overlaps with the sequences of the splice-sites.
Dementia
According to a research study conducted Hutton, M et al, a missense mutation occurring on the 5' region of the RNA associated with the tau protein was found to be correlated with inherited dementia (known as FTDP-17). The splice-site mutations all destabilize a potential stem–loop structure which is most likely involved in regulating the alternative splicing of exon10 in chromosome 17. Consequently, more usage occurs on the 5' splice site and an increased proportion of tau transcripts that include exon 10 are created. Such drastic increase in mRNA will increase the proportion of Tau containing four microtubule-binding repeats, which is consistent with the neuropathology described in several families with FTDP-17, a type inherited dementia.
Epilepsy
Some types of epilepsy may be brought on due to a splice site mutation.
In addition to a mutation in a stop codon, a splice site mutation on the 3' strand was found in a gene coding for cystatin B in Progressive Myoclonus Epilepsy patients. This combination of mutations was not found in unaffected individuals. By comparing sequences with and without the splice site mutation, investigators were able to determine that a G-to-C nucleotide transversion occurs at the last position of the first intron. This transversion occurs in the region that codes for the cystatin B gene. Individuals suffering from Progressive Myoclonus Epilepsy possess a mutated form of this gene, which results in decreased output of mature mRNA, and subsequently decreases in protein expression.
A study has also shown that a type of Childhood Absence Epilepsy (CAE) causing febrile seizures may be linked to a splice site mutation in the sixth intron of the GABRG2 gene. This splice site mutation was found to cause a nonfunctional GABRG2 subunit in affected individuals. According to this study, a point mutation was the culprit for the splice-donor site mutation, which occurred in intron 6. A nonfunctional protein product is produced, leading to the also nonfunctional subunit.
Hematological Disorders
Several genetic diseases may be the result of splice site mutations. For example, mutations that cause the incorrect splicing of β-globin mRNA are responsible of some cases of β-thalassemia. Another Example is TTP (thrombotic thrombocytopenic purpura). TTP is caused by deficiency of ADAMTS-13. A splice site mutation of ADAMTS-13 gene can therefore cause TTP. It is estimated that 15% of all point mutations causing human genetic diseases occur within a splice site.
Parathyroid Deficiency
When a splice site mutation occurs in intron 2 of the gene that produces the parathyroid hormone, a parathyroid deficiency can prevail. In one particular study, a G to C substitution in the splice site of intron 2 produces a skipping effect in the messenger RNA transcript. The exon that is skipped possesses the initiation start codon to produce parathyroid hormone. Such failure in initiation causes the deficiency.
Analysis
Using the model organism Drosophila melanogaster, data has been compiled regarding the genomic information and sequencing of this organism. A prediction model exists in which a researcher can upload his or her genomic information and use a splice site prediction database to gather information about where the splice sites could be located. The Berkeley Drosophila Project can be used to incorporate this research, as well as annotate high quality euchromatic data. The splice site predictor can be a great tool for researchers studying human disease in this model organism.
Splice site mutations can be analyzed using information theory.
References
Mutation
Gene expression | Splice site mutation | [
"Chemistry",
"Biology"
] | 1,610 | [
"Gene expression",
"Molecular genetics",
"Cellular processes",
"Molecular biology",
"Biochemistry"
] |
5,707,971 | https://en.wikipedia.org/wiki/Weierstrass%20product%20inequality | In mathematics, the Weierstrass product inequality states that for any real numbers 0 ≤ x1, ..., xn ≤ 1 we have
and similarly, for 0 ≤ x1, ..., xn,
where
The inequality is named after the German mathematician Karl Weierstrass.
Proof
The inequality with the subtractions can be proven easily via mathematical induction. The one with the additions is proven identically. We can choose as the base case and see that for this value of we get
which is indeed true. Assuming now that the inequality holds for all natural numbers up to , for we have:
which concludes the proof.
References
Inequalities | Weierstrass product inequality | [
"Mathematics"
] | 138 | [
"Binary relations",
"Mathematical relations",
"Inequalities (mathematics)",
"Mathematical problems",
"Mathematical theorems"
] |
5,708,385 | https://en.wikipedia.org/wiki/Omega%20Chi%20Epsilon | Omega Chi Epsilon (or , sometimes simplified to OXE) is an International honor society for chemical engineering students.
History
The first chapter of Omega Chi Epsilon was formed at the University of Illinois in 1931 by a group of chemical engineering students. These Founders were:
F. C. Howard
A. Garrell Deem
Ethan M. Stifle
John W. Bertetti
Professors D.B. Keyes and Norman Krase supported the students in their efforts. The Beta chapter was formed in the Iowa State University 1932.
The society grew slowly at first. Baird's Manual indicates there were six chapters by 1957, of which three were inactive. However, interest was revived in the 1960s, allowing a sustained growth that has continued to the present day. There are approximately eighty active chapters of the society as of 2021.
Omega Chi Epsilon amended its constitution to permit women to become members as of 1966. The organization became a member of the Association of College Honor Societies in 1967.
Symbols
The society's name comes from its motto "Ode Chrototos Eggegramai" or "In this Society, professionalism is engraved in our minds". The Greek letters ΩΧΕ were chosen to stand for "Order of Chemical Engineers".
The society's official seal is made of two concentric circles, bearing at the top, center the words "Omega Chi Epsilon" with the words "Founded, 1931" at the bottom center. The letters of the society appear in the center of the seal. The society's colors are black, white, and maroon.
The society's badge is a black Maltese cross background, on which is superimposed a circular maroon crest. The crest bears the letters ΩΧΕ on a white band passing across the horizontal midline. Above the white band are two crossed retorts rendered in gold. Below the white band are a gold integral sign and a lightning bolt. These symbols are noted to represent the roles of chemistry, mathematics, and physics in chemical engineering.
Activities
Chapter traditions of service to their chemical engineering departments commonly prevail rather than broader, national traditions.
Membership
Membership is limited to chemical engineering juniors, seniors, and graduate students. Associate membership may be offered to professors or other members of the staff of institutions within the field.
Chapters
Omega Chi Epsilon has chartered 80 chapters at colleges and universities in the United States, Qatar, and the United Arab Emirates.
Governance
The Society's annual meeting is held at the same time and place as the annual meeting of the American Institute of Chemical Engineers.
Governance is vested in a national president, vice president, executive secretary, and treasurer. With the immediate past president, these constitute the Executive Committee. The current national president is Christi Luks of the Missouri University of Science and Technology.
See also
American Institute of Chemical Engineers
Honor society
Honor cord
Professional fraternities and sororities
References
External links
Omega Chi Epsilon homepage
Association of College Honor Societies
Engineering honor societies
Chemical engineering organizations
Student organizations established in 1931
1932 establishments in Illinois | Omega Chi Epsilon | [
"Chemistry",
"Engineering"
] | 604 | [
"Engineering societies",
"Chemical engineering",
"Chemical engineering organizations",
"Engineering honor societies"
] |
5,708,497 | https://en.wikipedia.org/wiki/Wall%20stud | Wall studs are framing components in timber or steel-framed walls, that run between the top and bottom plates. It is a fundamental element in frame building. The majority non-masonry buildings rely on wall studs, with wood being the most common and least-expensive material used for studs. Studs are positioned perpendicular to the wall they’re forming to give strength and create space for wires, pipes and insulation. Studs are sandwiched between two horizontal boards called top and bottom plates. These boards are nailed or screwed to the top and bottom ends of the studs, forming the complete wall frame. Studs are usually spaced 16 in. or 24 in. apart.
Etymology
Stud is an ancient word related to similar words in Old English, Old Norse, Middle High German, and Old Teutonic generally meaning prop or support. Other historical words with similar meaning are quarter and scantling (one sense meaning a smaller timber, not necessarily the same use). Stick is a colloquial term for both framing lumber (timber) and a "timber tree" (a tree trunk good for using as lumber (timber)); thus, the names "stick and platform", "stick and frame", "stick and box", or simply stick framing. The stud height usually determines the ceiling height, thus sayings like: "...These rooms were usually high in stud..."
Purpose
Studs form walls and may carry vertical structural loads or be non load-bearing, such as in partition walls, which only separate spaces. They hold in place the windows, doors, interior finish, exterior sheathing or siding, insulation and utilities and help give shape to a building. Studs run from sill plate to wall plate. In modern construction, studs are anchored to the plates in a way, such as using fasteners, to prevent the building from being lifted off the foundation by severe wind or earthquake.
Properties
Studs are usually slender, so more studs are needed than in post and beam framing. Sometimes studs are long, as in balloon framing, where the studs extend two stories and carry a ledger which carries joists. Balloon framing has been made illegal in new construction in many jurisdictions for fire safety reasons because the open wall cavities allow fire to quickly spread such as from a basement to an attic; the plates and platforms in platform framing provide a passive fire stop inside the walls, and so are deemed much safer by fire safety officials. Being thinner and lighter, stick construction techniques are easier to cut and carry and is speedier than the timber framing.
In the United States and Canada, studs are traditionally made of wood, usually 2×4 or 2×6 by name; however, these historical dimensions have been reduced but still carry the name of "two by four" and "two by six". Typical dimensions of today's "two by four" is dimensional lumber prior to sanding and are typically placed from each other's center, but sometimes also at or . The wood needs to be dry when used, or problems may occur as the studs shrink and twist as they dry out. Steel studs are gaining popularity as a non-combustible alternative, especially for non load-bearing walls, and are required in some firewalls.
In New Zealand, the required lumber size and spacing of wall studs are determined using NZS 3604 Timber-framed buildings table 8.2 for loadbearing walls and table 8.4 for non-loadbearing walls.
Other terms
The studs used to frame around window and door openings are sometimes given different names, including:
king stud − stud to left or right of a window or door that is continuous from the bottom plate to the top plate
queen stud - stud used as a repetitive member that is angled so as to be neither vertical nor horizontal.
trimmer or jack − stud to the left or right of a window or door that runs from the bottom plate to the underside of a lintel or header
cripple stud – a stud located either above or below a framed opening, that does not run the full height of the wall
post or column − a doubled or other integral multiple of a group of studs nailed side by side. Posts in walls are used at point loads such as long spans near a wide window or sliding door, etc.
sleeper or nailer - a stud laid flat to other framing members to provide a point of attachment.
sill - a stud sized member forming the base of a window assembly or the base of wall.
mudsill - a stud sized member that forms the base of a wall and has been treated against insects and decay.
top plate or double top plate - a stud sized member that forms the top of the wall. In cases where other members must bear or brace on the top of the wall a double top plate is used with the member using offset laps so the top plate provides a continuous bearing surface.
A building technique mostly associated with Lincolnshire, England, and parts of Scotland gets part of its name from the studs: mud and stud (stud and mud). This building method uses studs in a framework which is then totally covered with mud which resembles the building material cob. Another traditional building method is called stud and plaster where the plaster walls are held by lath on the studs. Studs are also the namesake of a type of timber framing called close studding.
Grades
Based on the American West Coast Lumber Inspection Bureau (WCLIB) grading rules, there is only one grade of stud: STUD. A stud is graded for vertical application and its stress requirements and allowable visual defects reflect that application. A stud is most similar to a #2 grade, which is held to a higher standard during grading. The biggest difference between the two is the frequency, placement and size of knots and overall allowable wane.
See also
Furring
Stud finder
References
External links
Building engineering
Structural system
Carpentry | Wall stud | [
"Technology",
"Engineering"
] | 1,211 | [
"Structural engineering",
"Building engineering",
"Structural system",
"Civil engineering",
"Architecture"
] |
5,708,623 | https://en.wikipedia.org/wiki/Lipotropin | Lipotropin is the name for two hormones produced by the cleavage of pro-opiomelanocortin (POMC). The anterior pituitary gland produces the pro-hormone POMC, which is then cleaved again to form adrenocorticotropin (ACTH) and β-lipotropin (β-LPH).
β-Lipotropin
β-Lipotropin is a 90-amino acid polypeptide that is the carboxy-terminal fragment of POMC. It was initially reported to stimulate melanocytes to produce melanin. It was also reported to perform lipid-mobilizing functions such as lipolysis and steroidogenesis. However, no subsequent studies have been published that support these early findings and no receptor has been identified for β-lipotropin.
β-Lipotropin can be cleaved into smaller peptides. In humans, γ-lipotropin, β-MSH, and β-endorphin, are all possible fragments of β-lipotropin. β-endorphin is the predominant opioid of the anterior human and rat pituitary gland. Birdsall and Hulme demonstrated that the C-fragment of lipotropin (β-endorphin) has a high affinity for opiate receptors in the brain, and the binding was reversed by naloxone, a classical antagonist of the opiates (Bradbury et al. 1976a). Alongside this, Feldberg found that β-endorphin administered in cat ventricles was 100 times more potent than morphine as an analgesic agent (Feldberg & Smyth 1976, 1977) and the analgesia persisted for several hours. Feldberg concluded that β-endorphin was the most potent analgesic agent known.
β-Lipotropin is found in essentially equimolar concentrations to that of corticotropin. Evidence shows that β-Lipotropin is metabolized into endorphins that can greatly affect mood and behavior and is thus regarded as a prohormone.
γ-Lipotropin
γ-lipotropin is the amino-terminal peptide fragment of β-lipotropin. In humans, it has 56 amino acids. Gamma lipotropin is identical to the first 56 amino acid sequences of β-lipotropin. It can be cleaved to β-melanocyte stimulating hormone.
In sheep, gamma-lipotropic hormone is a 58-amino-acid long pituitary polypeptide formed from the first 58 residues of beta-lipotropic hormone. The carboxyl-terminal of gamma-lipotropic hormone is identical to the structure of beta-melanophore-stimulating hormone.
Use in pain relief
β-endorphin has been determined to have an analgesic effect. It produces effects
similar to or characteristic of morphine.
Use in sport
Lipotropin is on the Prohibited List of substances by the World Anti Doping Agency. Lipotropin has also, under its alternate name AOD-9604 (Anti-Obesity Drug-9604), been connected with controversies in Australian Rules Football. Allegations have arisen around the use of the drug and its administration to players of the Essendon Football Club in the Essendon Football Club supplements saga, including weekly administration to players in the 2012 season. The matters are currently under investigation due to the relationship between Lipotropin and growth hormones, as noted by club medical staff.
Clinical trials
In 2020 AOD-9604 underwent clinical trials into its use for the treatment of pain.
References
External links
Tumor markers | Lipotropin | [
"Chemistry",
"Biology"
] | 776 | [
"Biomarkers",
"Tumor markers",
"Molecular biology stubs",
"Molecular biology",
"Chemical pathology"
] |
5,708,669 | https://en.wikipedia.org/wiki/Dowker%E2%80%93Thistlethwaite%20notation | In the mathematical field of knot theory, the Dowker–Thistlethwaite (DT) notation or code, for a knot is a sequence of even integers. The notation is named after Clifford Hugh Dowker and Morwen Thistlethwaite, who refined a notation originally due to Peter Guthrie Tait.
Definition
To generate the Dowker–Thistlethwaite notation, traverse the knot using an arbitrary starting point and direction. Label each of the n crossings with the numbers 1, ..., 2n in order of traversal (each crossing is visited and labelled twice), with the following modification: if the label is an even number and the strand followed crosses over at the crossing, then change the sign on the label to be a negative. When finished, each crossing will be labelled a pair of integers, one even and one odd. The Dowker–Thistlethwaite notation is the sequence of even integer labels associated with the labels 1, 3, ..., 2n − 1 in turn.
Example
For example, a knot diagram may have crossings labelled with the pairs (1, 6) (3, −12) (5, 2) (7, 8) (9, −4) and (11, −10). The Dowker–Thistlethwaite notation for this labelling is the sequence: 6 −12 2 8 −4 −10.
Uniqueness and counting
Dowker and Thistlethwaite have proved that the notation specifies prime knots uniquely, up to reflection.
In the more general case, a knot can be recovered from a Dowker–Thistlethwaite sequence, but the recovered knot may differ from the original by either being a reflection or by having any connected sum component reflected in the line between its entry/exit points – the Dowker–Thistlethwaite notation is unchanged by these reflections. Knots tabulations typically consider only prime knots and disregard chirality, so this ambiguity does not affect the tabulation.
The ménage problem, posed by Tait, concerns counting the number of different number sequences possible in this notation.
See also
Alexander–Briggs notation
Conway notation
Gauss notation
References
Further reading
External links
DT Notation, Knotinfo
What are Gauss and Dowker-Thistlethwaite codes?
Knot theory
Mathematical notation | Dowker–Thistlethwaite notation | [
"Mathematics"
] | 457 | [
"nan"
] |
5,709,055 | https://en.wikipedia.org/wiki/Cicho%C5%84%27s%20diagram | In set theory,
Cichoń's diagram or Cichon's diagram is a table of 10 infinite cardinal numbers related to the set theory of the reals displaying the provable relations between these
cardinal characteristics of the continuum. All these cardinals are greater than or equal to , the smallest uncountable cardinal, and they are bounded above by , the cardinality of the continuum. Four cardinals describe properties of the ideal of sets of measure zero; four more describe the corresponding properties of the ideal of meager sets (first category sets).
Definitions
Let I be an ideal of a fixed infinite set X, containing all finite subsets of X. We define the following "cardinal coefficients" of I:
The "additivity" of I is the smallest number of sets from I whose union is not in I any more. As any ideal is closed under finite unions, this number is always at least ; if I is a σ-ideal, then add(I) ≥ .
The "covering number" of I is the smallest number of sets from I whose union is all of X. As X itself is not in I, we must have add(I) ≤ cov(I).
The "uniformity number" of I (sometimes also written ) is the size of the smallest set not in I. By our assumption on I, add(I) ≤ non(I).
The "cofinality" of I is the cofinality of the partial order (I, ⊆). It is easy to see that we must have non(I) ≤ cof(I) and cov(I) ≤ cof(I).
Furthermore, the "bounding number" or "unboundedness number" and the "dominating number" are defined as follows:
where "" means: "there are infinitely many natural numbers n such that …", and "" means "for all except finitely many natural numbers n we have …".
Diagram
Let be the σ-ideal of those subsets of the real line that are meager (or "of the first category") in the euclidean topology, and let
be the σ-ideal of those subsets of the real line that are of Lebesgue measure zero. Then the following inequalities hold:
Where an arrow from to is to mean that . In addition, the following relations hold:
It turns out that the inequalities described by the diagram, together with the relations mentioned above, are all the relations between these cardinals that are provable in ZFC, in the following limited sense. Let A be any assignment of the cardinals and to the 10 cardinals in Cichoń's diagram. Then if A is consistent with the diagram's relations, and if A also satisfies the two additional relations, then A can be realized in some model of ZFC.
For larger continuum sizes, the situation is less clear. It is consistent with ZFC that all of the Cichoń's diagram cardinals are simultaneously different apart from and (which are equal to other entries).
Some inequalities in the diagram (such as "add ≤ cov") follow immediately from the definitions. The inequalities and
are classical theorems
and follow from the fact that the real line can be partitioned into a meager set and a set of measure zero.
Remarks
The British mathematician David Fremlin named the diagram after the Polish mathematician from Wrocław, .
The continuum hypothesis, of being equal to , would make all of these relations equalities.
Martin's axiom, a weakening of the continuum hypothesis, implies that all cardinals in the diagram (except perhaps ) are equal to .
Similar diagrams can be drawn for cardinal characteristics of higher cardinals for strongly inaccessible, which assort various cardinals between and .
References
Cardinal numbers
Descriptive set theory | Cichoń's diagram | [
"Mathematics"
] | 779 | [
"Cardinal numbers",
"Mathematical objects",
"Numbers",
"Infinity"
] |
5,709,846 | https://en.wikipedia.org/wiki/Artistic%20inspiration | Inspiration (from the Latin inspirare, meaning "to breathe into") is an unconscious burst of creativity in a literary, musical, or visual art and other artistic endeavours. The concept has origins in both Hellenism and Hebraism. The Greeks believed that inspiration or "enthusiasm" came from the muses, as well as the gods Apollo and Dionysus. Similarly, in the Ancient Norse religions, inspiration derives from the gods, such as Odin. Inspiration is also a divine matter in Hebrew poetics. In the Book of Amos the prophet speaks of being overwhelmed by God's voice and compelled to speak. In Christianity, inspiration is a gift of the Holy Spirit.
In the 18th century philosopher John Locke proposed a model of the human mind in which ideas associate or resonate with one another in the mind. In the 19th century, Romantic poets such as Coleridge and Shelley believed that inspiration came to a poet because the poet was attuned to the (divine or mystical) "winds" and because the soul of the poet was able to receive such visions. In the early 20th century, psychoanalyst Sigmund Freud believed himself to have located inspiration in the inner psyche of the artist. Psychiatrist Carl Gustav Jung's theory of inspiration suggests that an artist is one who was attuned to their creative instinct which encoded the archetypes of the human mind.
The Marxist theory of art sees it as the expression of the friction between economic base and economic superstructural positions, or as an unaware dialog of competing ideologies, or as an exploitation of a "fissure" in the ruling class's ideology. In modern psychology inspiration is not frequently studied, but it is generally seen as an entirely internal process.
History of the concepts
Ancient models of inspiration
In Greek thought, inspiration meant that the poet or artist would go into ecstasy or furor poeticus, the divine frenzy or poetic madness. The artist would be transported beyond their own mind and given the gods' or goddesses own thoughts to embody.
Inspiration is prior to consciousness and outside of skill (ingenium in Latin). Technique and performance are independent of inspiration, and therefore it is possible for the non-poet to be inspired and for a poet or painter's skill to be insufficient to the inspiration. In Hebrew poetics, inspiration is similarly a divine matter. In the Book of Amos, 3:8 the prophet speaks of being overwhelmed by God's voice and compelled to speak. However, inspiration is also a matter of revelation for the prophets, and the two concepts are intermixed to some degree. Revelation is a conscious process, where the writer or painter is aware and interactive with the vision, while inspiration is involuntary and received without any complete understanding.
In Christianity, inspiration is a gift of the Holy Spirit. Saint Paul said that all scripture is given by inspiration of God (2 Timothy) and the account of Pentecost records the Holy Spirit descending with the sound of a mighty wind. This understanding of "inspiration" is vital for those who maintain Biblical literalism, for the authors of the scriptures would, if possessed by the voice of God, not "filter" or interpose their personal visions onto the text. For church fathers like Saint Jerome, David was the perfect poet, for he best negotiated between the divine impulse and the human consciousness.
In northern societies, such as Old Norse, inspiration was likewise associated with a gift of the gods. As with the Greek, Latin, and Romance literatures, Norse skalds were inspired by a magical and divine state and then shaped the words with their conscious minds. Their training was an attempt to learn to shape forces beyond the human. In the Venerable Bede's account of Cædmon, the Christian and later Germanic traditions combine. Cædmon was a herder with no training or skill at verse. One night, he had a dream where Jesus asked him to sing. He then composed "Cædmon's Hymn", and from then on was a great poet. Inspiration in the story is the product of grace: it is unsought (though desired), uncontrolled, and irresistible, and the poet's performance involves his whole mind and body, but it is fundamentally a gift.
Renaissance revival of furor poeticus
The Greco-Latin doctrine of the divine origin of poetry was available to medieval authors through the writings of Horace (on Orpheus) and others, but it was the Latin translations and commentaries by the neo-platonic author Marsilio Ficino of Plato's dialogues Ion and (especially) Phaedrus at the end of the 15th century that led to a significant return of the conception of furor poeticus. Ficino's commentaries explained how gods inspired the poets, and how this frenzy was subsequently transmitted to the poet's auditors through his rhapsodic poetry, allowing the listener to come into contact with the divine through a chain of inspiration. Ficino himself sought to experience ecstatic rapture in rhapsodic performances of Orphic-Platonic hymns accompanied by a lyre.
The doctrine was also an important part of the poetic program of the French Renaissance poets collectively referred to as La Pléiade (Pierre de Ronsard, Joachim du Bellay, etc.); a full theory of divine fury / enthusiasm was elaborated by Pontus de Tyard in his Solitaire Premier, ou Prose des Muses, et de la fureur poétique (Tyard classified four kinds of divine inspiration: (1) poetic fury, gift of the Muses; (2) knowledge of religious mysteries, through Bacchus; (3) prophecy and divination through Apollo; (4) inspiration brought on by Venus/Eros.)
Enlightenment and Romantic models
In the 18th century in England, nascent psychology competed with a renascent celebration of the mystical nature of inspiration. John Locke's model of the human mind suggested that ideas associate with one another and that a string in the mind can be struck by a resonant idea. Therefore, inspiration was a somewhat random but wholly natural association of ideas and sudden unison of thought. Additionally, Lockean psychology suggested that a natural sense or quality of mind allowed persons to see unity in perceptions and to discern differences in groups. This "fancy" and "wit," as they were later called, were both natural and developed faculties that could account for greater or lesser insight and inspiration in poets and painters. Imagination, the Romantics argued, is a tool to see things that the intelligence is blind to.
The musical model was satirized, along with the afflatus, and "fancy" models of inspiration, by Jonathan Swift in A Tale of a Tub. Swift's narrator suggests that madness is contagious because it is a ringing note that strikes "chords" in the minds of followers and that the difference between an inmate of Bedlam and an emperor was what pitch the insane idea was. At the same time, he satirized "inspired" radical Protestant ministers who preached through "direct inspiration." In his prefatory materials, he describes the ideal dissenter's pulpit as a barrel with a tube running from the minister's posterior to a set of bellows at the bottom, whereby the minister could be inflated to such an extent that he could shout out his inspiration to the congregation. Furthermore, Swift saw fancy as an antirational, mad quality, where, "once a man's fancy gets astride his reason, common sense is kick't out of doors."
The divergent theories of inspiration that Swift satirized would continue, side by side, through the 18th and 19th centuries. Edward Young's Conjectures on Original Composition was pivotal in the formulation of Romantic notions of inspiration. He said that genius is "the god within" the poet who provides the inspiration. Thus, Young agreed with psychologists who were locating inspiration within the personal mind (and significantly away from the realm either of the divine or demonic) and yet still positing a supernatural quality. Genius was an inexplicable, possibly spiritual and possibly external, font of inspiration. In Young's scheme, the genius was still somewhat external in its origin, but Romantic poets would soon locate its origin wholly within the poet. Romantic writers such as Ralph Waldo Emerson (The Poet), and Percy Bysshe Shelley saw inspiration in terms similar to the Greeks: it was a matter of madness and irrationality.
Inspiration came because the poet tuned himself to the (divine or mystical) "winds" and because he was made in such a way as to receive such visions. Samuel Taylor Coleridge's accounts of inspiration were the most dramatic, and his The Eolian Harp was only the best of the many poems Romantics would write comparing poetry to a passive reception and natural channelling of the divine winds. The story he told about the composition of Kubla Khan has the poet reduced to the level of scribe. William Butler Yeats would later experiment and value automatic writing. Inspiration was evidence of genius, and genius was a thing that the poet could take pride in, even though he could not claim to have created it himself.
Modernist and modern concepts
Sigmund Freud and other later psychologists located inspiration in the inner psyche of the artist. The artist's inspiration came out of unresolved psychological conflict or childhood trauma. Further, inspiration could come directly from the unconscious. Like the Romantic genius theory and the revived notion of "poetic phrenzy," Freud saw artists as fundamentally special, and fundamentally wounded. Because Freud situated inspiration in the unconscious mind, Surrealist artists sought out this form of inspiration by turning to dream diaries and automatic writing, the use of Ouija boards and found poetry to try to tap into what they saw as the true source of art. Carl Gustav Jung's theory of inspiration reiterated the other side of the Romantic notion of inspiration indirectly by suggesting that an artist is one who was attuned to something impersonal, something outside of the individual experience: racial memory, or a 'Psychopoetry' experience.
Materialist theories of inspiration again diverge between purely internal and purely external sources. Karl Marx did not treat the subject directly, but the Marxist theory of art sees it as the expression of the friction between economic base and economic superstructural positions, or as an unaware dialog of competing ideologies, or as an exploitation of a "fissure" in the ruling class's ideology. Therefore, where there have been fully Marxist schools of art, such as Soviet Realism, the "inspired" painter or poet was also the most class-conscious painter or poet, and "formalism" was explicitly rejected as decadent (e.g. Sergei Eisenstein's late films condemned as "formalist error"). Outside of state-sponsored Marxist schools, Marxism has retained its emphasis on the class consciousness of the inspired painter or poet, but it has made room for what Frederic Jameson called a "political unconscious" that might be present in the artwork. However, in each of these cases, inspiration comes from the artist being particularly attuned to receive the signals from an external crisis.
In modern psychology, inspiration is not frequently studied, but it is generally seen as an entirely internal process. In each view, however, whether empiricist or mystical, inspiration is, by its nature, beyond control.
An example of a modern study on inspiration is one that was conducted by Takeshi Okada and Kentaro Ishibashi, published in 2016 in the multidisciplinary journal, Cognitive Science. In this three-part study, groups of Japanese undergraduate art students were observed to determine whether copying or simply musing upon example artworks that served as their inspiration would increase their creative output. The results of the first and second experiment revealed that copying artwork enabled the students to produce creative drawings that were qualitatively different, but only when the example—the inspiration—featured a style that was unfamiliar to the students. The third experiment revealed that only musing upon the unfamiliar inspiration produced the same effect as copying it. Okada and Ishibashi suggest that these unfamiliar examples were able to facilitate the creativity of the students because they challenged the students' perspectives on drawing. They admit, however, that it is unclear whether their results can be generalized to professional artists as well, but they cite examples of artists, namely Pablo Picasso and Vincent van Gogh, who extensively imitated the work of other artists, which might suggest that "imitation is an effective driver of creativity, even for experts."
See also
Afflatus, the Romantic concept of inspiration
Automatic writing
Divine spark
Epiphany (feeling)
Genius (literature), the development of the concept of the genius from daemon to innate gift
Glossolalia (or speaking in tongues)
Muses, the classical sources of inspiration
References
Brogan, T.V.F. "Inspiration" in Alex Preminger and T.V.F. Brogan, eds., The New Princeton Encyclopedia of Poetry and Poetics. Princeton, NJ: Princeton University Press, 1993. 609–610.
Aesthetics
Poetics
Creativity
Positive mental attitude | Artistic inspiration | [
"Biology"
] | 2,689 | [
"Creativity",
"Behavior",
"Human behavior"
] |
5,709,955 | https://en.wikipedia.org/wiki/Parking%20sensor | Parking sensors are proximity sensors for road vehicles designed to alert the driver of obstacles while parking. These systems use either electromagnetic or ultrasonic sensors.
Ultrasonic systems
These systems feature ultrasonic proximity detectors to measure the distances to nearby objects via sensors located in the front and/or rear bumper fascias or visually minimized within adjacent grills or recesses.
The sensors emit acoustic pulses, with a control unit measuring the return interval of each reflected signal and calculating object distances. The system in turns warns the driver with acoustic tones, the frequency indicating object distance, with faster tones indicating closer proximity and a continuous tone indicating a minimal pre-defined distance. Systems may also include visual aids, such as LED or LCD readouts to indicate object distance. A vehicle may include a vehicle pictogram on the car's infotainment screen, with a representation of the nearby objects as coloured blocks.
Rear sensors may be activated when reverse gear is selected and deactivated as soon as any other gear is selected. Front sensors may be activated manually and deactivated automatically when the vehicle reaches a pre-determined speed to avoid subsequent nuisance warnings.
As an ultrasonic systems relies on the reflection of sound waves, the system may not detect flat objects or object insufficiently large to reflect sound (e.g., a narrow pole or a longitudinal object pointed directly at the vehicle or near an object). Objects with flat surfaces angled from the vertical may deflect return sound waves away from the sensors, hindering detection. Also soft object with strong sound absorption may have weaker detection, e.g. wool or moss.
Electromagnetic systems
The electromagnetic parking sensor (EPS) was re-invented and patented in 1992 by Mauro Del Signore. Electromagnetic sensors rely on the vehicle moving slowly and smoothly towards the object to be avoided. Once an obstacle is detected, the sensor continues to signal the presence of the obstacle even if the vehicle momentarily stops. If the vehicle then resumes moving backwards the alarm signal becomes louder as the obstacle is approached. Electromagnetic parking sensors are often sold as not requiring any holes to be drilled offering a unique design that discreetly mounts on the inner side of the bumper preserving the 'new factory look' of your vehicle.
Blind spot monitors and other technology
Blind spot monitors are an option that may include more than monitoring the sides of the vehicle. It can include "Cross Traffic Alert," which alerts drivers of oncoming traffic behind them while backing out of a parking space.
In the United States, backup cameras have been required on all new cars since 2018.
Inventors
The Parking Sensor, a spin-off from the travel aid for the blind, the Sonic Pathfinder, was first invented by Dr Tony Heyes at the University of Nottingham. England. Toyota introduced ultrasonic Back Sonar on the 1982 Toyota Corona, offering it until 1988. On December 13, 1984, Massimo Ciccarello and Ruggero Lenci (see List of Italian inventors) entered in Italy the patent request for ultrasonics Parking sensors, and on November 16, 1988, the Ministry of Industry granted them the Patent for industrial invention n. 1196650.
See also
Automatic parking
Backup collision
Backup camera
Blind spot monitor
Blind spot (vehicle)
Intelligent Parking Assist System
Experimental Safety Vehicle (ESV)
Intelligent car
Lane departure warning system
Objects in mirror are closer than they appear
Omniview technology
Precrash system
Rear-view mirror
Side-view mirror
Wing mirror
References
External links
Reverse parking camera for cars in india
Proxel - Operating principle of Electromagnetic Parking Sensor
Parking Sensors patented in Italy
Advanced driver assistance systems
Sensors | Parking sensor | [
"Technology",
"Engineering"
] | 725 | [
"Sensors",
"Measuring instruments"
] |
5,710,033 | https://en.wikipedia.org/wiki/TRANZ%20330 | The TRANZ 330 is a popular point-of-sale device manufactured by VeriFone in 1985. The most common application for these units is bank and credit card processing, however, as a general purpose computer, they can perform other novel functions. Other applications include gift/benefit card processing, prepaid phone cards, payroll and employee timekeeping, and even debit and ATM cards. They are programmed in a proprietary VeriFone TCL language (Terminal Control Language), which is unrelated to the Tool Command Language used in UNIX environments.
Point of sale companies
Embedded systems
Payment systems
Banking equipment | TRANZ 330 | [
"Technology",
"Engineering"
] | 123 | [
"Embedded systems",
"Computer science",
"Computer engineering",
"Computer systems"
] |
5,710,256 | https://en.wikipedia.org/wiki/Effective%20torque | Effective torque (often referred to as wheel torque or torque to the wheels) is a concept primarily associated with automotive tuning. Torque can be measured using a dynamometer. Common units used in automotive applications can include foot-pounds and Newton·meters.
The formula for effective torque to the wheels is:
Tw = Te * N * η
N = N * N
η = η * η
... where Tw is wheel torque, Te is engine torque, N is the gear ratio, η is the efficiency, and the subscripts t and f are for the gearbox and differential, respectively. Effective torque is often 5-15% lower than the shaft or crank ratings of an engine due to drivetrain losses.
See also
Machine torque
References
Engine technology | Effective torque | [
"Technology"
] | 153 | [
"Engine technology",
"Engines"
] |
5,710,507 | https://en.wikipedia.org/wiki/Pornography | Pornography (colloquially called porn or porno) is sexually suggestive material, such as a picture, video, text, or audio, intended for sexual arousal. Made for consumption by adults, pornographic depictions have evolved from cave paintings, some forty millennia ago, to modern-day virtual reality presentations. A general distinction of adults-only sexual content is made, classifying it as pornography or erotica.
The oldest artifacts considered pornographic were discovered in Germany in 2008 and are dated to be at least 35,000 years old. Human enchantment with sexual imagery representations has been a constant throughout history. However, the reception of such imagery varied according to the historical, cultural, and national contexts. The Indian Sanskrit text Kama Sutra (3rd century CE) contained prose, poetry, and illustrations regarding sexual behavior, and the book was celebrated; while the British English text Fanny Hill (1748), considered "the first original English prose pornography," has been one of the most prosecuted and banned books. In the late 19th century, a film by Thomas Edison that depicted a kiss was denounced as obscene in the United States, whereas Eugène Pirou's 1896 film Bedtime for the Bride was received very favorably in France. Starting from the mid-twentieth century on, societal attitudes towards sexuality became lenient in the Western world where legal definitions of obscenity were made limited. In 1969, Blue Movie by Andy Warhol became the first film to depict unsimulated sex that received a wide theatrical release in the United States. This was followed by the "Golden Age of Porn" (1969–1984). The introduction of home video and the World Wide Web in the late 20th century led to global growth in the pornography business. Beginning in the 21st century, greater access to the Internet and affordable smartphones made pornography more mainstream.
Pornography has been vouched to provision a safe outlet for sexual desires that may not be satisfied within relationships and be a facilitator of sexual fulfillment in people who do not have a partner. Pornography consumption is found to induce psychological moods and emotions similar to those evoked during sexual intercourse and casual sex. Pornography usage is considered a widespread recreational activity in-line with other digitally mediated activities such as use of social media or video games. People who regard porn as sex education material were identified as more likely not to use condoms in their own sex life, thereby assuming a higher risk of contracting sexually transmitted infections (STIs); performers working for pornographic studios undergo regular testing for STIs unlike much of the general public. Comparative studies indicate higher tolerance and consumption of pornography among adults tends to be associated with their greater support for gender equality. Among feminist groups, some seek to abolish pornography believing it to be harmful, while others oppose censorship efforts insisting it is benign. A longitudinal study ascertained that pornography use is not a predictive factor in intimate partner violence. Porn Studies, started in 2014, is the first international peer-reviewed, academic journal dedicated to the critical study of "products and services" deemed pornographic.
Pornography is a major influencer of people's perception of sex in the digital age; numerous pornographic websites rank among the top 50 most visited websites worldwide. Called an "erotic engine", pornography has been noted for its key role in the development of various communication and media processing technologies. For being an early adopter of innovations and a provider of financial capital, the pornography industry has been cited to be a contributing factor in the adoption and popularization of media related technologies. The exact economic size of the porn industry in the early twenty-first century is unknown. In 2023, estimates of the total market value stood at over US$172 billion. The legality of pornography varies across countries. From the mid-2010s, unscrupulous pornography such as deepfake pornography and revenge porn have become issues of concern.
Etymology and definition
The word pornography is a conglomerate of two ancient Greek words: () "fornicators",
and () "writing, recording, or description". In Greek language, the term pornography connotes depiction of sexual activity; no date is known for the first use of the term pornography, the earliest attested, most related word found is () i.e. "someone writing about harlots" in the 3rd century CE work Deipnosophists by Athenaeus.
The oldest published reference to the word pornography as in 'new pornographie,' is dated back to 1638 and is credited to Nathaniel Butter in a history of the Fleet newspaper industry. The modern word pornography entered the English language as the more familiar word in 1842 via French "," from Greek "".
The term porn is an abbreviation of pornography. The related term () "prostitute" in Greek, originally meant "bought, purchased" similar to "to sell", from the proto-Indo-European root per-, "to hand over" — alluding to act of selling.
The word pornography was originally used by classical scholars as "a bookish, and therefore inoffensive term for writing about prostitutes", but its meaning was quickly expanded to include all forms of "objectionable or obscene material in art and literature". In 1864, Webster's Dictionary published "a licentious painting" as the meaning for pornography, and the Oxford English Dictionary: "obscene painting" (1842), "description of obscene matters, obscene publication" (1977 or earlier).
Definitions for the term "pornography" are varied, with people from both pro- and anti-pornography groups defining it either favorably or unfavorably, thus making any definition very stipulative. Nevertheless, academic researchers have defined pornography as sexual subject material such as a picture, video, text, or audio that is primarily intended to assist sexual arousal in the consumer, and is created and commercialized with "the consent of all persons involved". Arousal is considered the primary objective, the raison d'etre a material must fulfill for it to be treated as pornographic. As some people can feel aroused by an image that is not meant for sexual arousal and conversely cannot feel aroused by material that is clearly intended for arousal, the material that can be considered as pornography becomes subjective.
Pornography throughout history
Pornography from ancient times
Pornography is viewed by historians as a complex cultural formation. Depictions of a sexual nature existed since prehistoric times as seen in Venus figurines and rock art. People across various civilizations created works that depicted explicit sex; these include artifacts, music, poetry, and murals among other things that are often intertwined with religious and supernatural themes. The oldest artifacts, including the Venus of Hohle Fels, which is considered to be borderline pornographic, were discovered in 2008 CE at a cave near Stuttgart in Germany, radiocarbon dating suggests they are at least 35,000 years old, from the Aurignacian period.
Vast number of artifacts discovered in ancient Mesopotamia region had explicit depictions of heterosexual sex. Glyptic art from the Sumerian Early Dynastic Period frequently showed scenes of frontal sex in the missionary position. In Mesopotamian votive plaques from the early second millennium (), a man is usually shown penetrating a woman from behind while she bends over drinking beer through a straw. Middle Assyrian lead votive figurines often portrayed a man standing and penetrating a woman as she rests on an altar. Scholars have traditionally interpreted all these depictions as scenes of hieros gamos (an ancient sacred marriage between a god and a goddess), but they are more likely to be associated with Inanna, the Mesopotamian goddess of sex and sacred prostitution. Many sexually explicit images, including models of male and female sexual organs were found in the temple of Inanna at Assur.
Depictions of sexual intercourse were not part of the general repertory of ancient Egyptian formal art, but rudimentary sketches of heterosexual intercourse have been found on pottery fragments and in graffiti. The final two thirds of the Turin Erotic Papyrus (Papyrus 55001), an Egyptian papyrus scroll discovered at Deir el-Medina, consists of a series of twelve vignettes showing men and women in various sexual positions. The scroll was probably painted in the Ramesside period (1292–1075 BCE) and its high artistic quality indicates that it was produced for a wealthy audience. No other similar scrolls have yet been discovered.
Archaeologist Nikolaos Stampolidis had noted that the society of ancient Greece held lenient attitudes towards sexual representation in the fields of art and literature. The Greek poet Sappho's Ode to Aphrodite (600 BCE) is considered an earliest example of lesbian poetry. Red-figure pottery invented in Greece (530 BCE) often portrayed images that displayed eroticism. The fifth-century BC comic Aristophanes elaborated 106 ways of describing the male genitalia and in 91 ways the female genitalia. Lysistrata (411 BCE) is a sex-war comedy play performed in ancient Greece.
In India, Hinduism embraced an inquisitive attitude towards sex as an art and a spiritual ideal. Some ancient Hindu temples incorporated various aspects of sexuality into their art work. The temples at Khajuraho and Konark are particularly renowned for their sculptures, which had detailed representations of human sexual activity. These depictions were viewed with a spiritual outlook as sexual arousal is believed to indicate the embodying of the divine.
"pornography is sometimes characterised as the symptom of a degenerate society, but anyone even noddingly familiar with Greek vases or statues on ancient Hindu temples will know that so-called unnatural sex acts, orgies and all manner of complex liaisons have for millennia past been represented in art for the pleasure and inspiration of the viewer everywhere. The desire to ponder images of love-making is clearly innate in the human – perhaps particularly the male – psyche." — Tom Hodgkinson
Kama, the word used to connote sexual desire, was explored in Indian literary works such as the Kama Sutra, which dealt with the practical as well as the psychological aspects of human courtship and sexual intercourse.
The Sanskrit text Kama sutra was compiled by the sage Vatsyayana into its final form sometime during the second half of the third century CE. This text, which included prose, poetry, as well as illustrations regarding erotic love and sexual behavior, is one of the most celebrated Indian erotic works. Koka shastra is another medieval Indian work that explored kama.
Pornography from the Roman era
When large-scale archaeological excavations were undertaken in the ancient Roman city of Pompeii during the 18th century, much of the erotic art in Pompeii and Herculaneum came to light, shocking the authorities who endeavored to hide them away from the general public. In 1821, the moveable objects were locked away in the Secret Museum in Naples, and what could not be removed was either covered or cordoned off from public view.
Other examples of early art and literature of sexual nature include: Ars Amatoria (Art of Love), a second-century CE treatise on the art of seduction and sensuality by the Roman poet Ovid; the artifacts of the Moche people in Peru (100 CE to 800 CE); The Decameron, a collection of short stories, some of which are sexual in nature by the 14th-century Italian author Giovanni Boccaccio; and the fifteenth-century Arabic sex manual The Perfumed Garden.
Pornography from early modern era
A highly developed culture of visual erotica flourished in Japan during the early modern era. From at least the 17th century, erotic artworks became part of the mainstream social culture. Depictions of sexual intercourse were often presented on pictures that were meant to provide sex education for medical professionals, courtesans, and married couples. Makura-e (pillow pictures) were made for entertainment as well as for the guidance of married couples. The ninth-century Japanese art form "Shunga", which depicted sexual acts on woodblock prints and paintings became so popular by the 18th century that the Japanese government began to issue official edicts against them. Even so, Japanese erotica flourished with the works of artists such as Suzuki Harunobu achieving worldwide fame. Japanese censorship laws enacted in 1870 made the production of erotic works difficult. The laws remained in effect until the end of the Pacific War in 1945; nevertheless, pornography flourished through the sale of "erotic, grotesque, nonsense" (ero-guro-nansensu) periodicals, particularly in the Taishō era (1912–1926). From the 1960s, pink films, which portrayed sexual themes became popular in Japan. In 1981 the first Japanese Adult video (AV) was released. The Japanese pornography industry peaked in the early 2000s when about 30,000 AVs were made a year. From the mid-2010s, increased availability of free porn on the Internet led to a decline in the production of AVs. Other forms of adult entertainment such as hentai, which refers to pornographic manga and anime, and erotic video games have become popular in recent decades.
In Europe, the Italian Renaissance work from the 16th century - I Modi (The Ways) also known as The Sixteen Pleasures became famous for its engravings that explicitly depicted sex positions.
The publication of this book was considered the beginning of print pornography in Rome. The second edition of this book was published in 1527, titled Aretino Postures, which combined erotic images with text - a first in the Western culture. The Vatican called for the complete destruction of all the copies of the book and imprisonment of its author Marcantonio Raimondi. With the development of printing press in Europe, the publication of written and visual material, which was essentially pornographic began. Heptaméron written in French by Marguerite de Navarre and published posthumously in 1558 is one of the earliest examples of salacious texts from this era. Beginning with the Age of Enlightenment and advances in printing technology, the production of erotic material became popular enough that an underground marketplace for such works developed in England with a separate publishing and bookselling business. Historians have identified the 18th century as an age of pornographic opulence. Written by anonymous authors, the titles: The Progress of Nature (1744); The History of the Human Heart: or, the Adventures of a Young Gentleman (1749), which had descriptions of female ejaculation; and The Child of Nature (1774) have been noted as prominent pornographic fictional works from this period. The book Fanny Hill (1748), is considered "the first original English prose pornography, and the first pornography to use the form of the novel." An erotic literary work by John Cleland, Fanny Hill was first published in England as Memoirs of a Woman of Pleasure. The novel has been one of the most prosecuted and banned books in history. The author John Cleland was charged for "corrupting the King's subjects."
At around the same time, erotic graphic art that began to be extensively produced in Paris came to be known in the Anglosphere as "French postcards". Enlightenment-era France had been noted by historians as the center of origin for modern-era pornography. The works of French pornography, which often concentrated on the education of an ingénue into libertine, dominated the sale of sexually explicit content. The French sought to interlace narratives of sexual pleasure with philosophical and anti-establishment basis. Political pornography began with the French Revolution (1789–99). Apart from the sexual component, pornography became a popular medium for protest against the social and political norms of the time. Pornography during this period was used to explore the ideas of sexual freedom for women and men, the various methods of contraception, and to expose the offenses of powerful royals and elites. The working and lower classes in France produced pornographic material en masse with themes of impotency, incest, and orgies that ridiculed the authority of the Church-State, aristocrats, priests,
monks, and other royalty.
One of the most important authors of socially radical pornography was the French aristocrat Marquis de Sade (1740–1814), whose name helped derive the words "sadism" and "sadist". He advocated libertine sexuality and published writings that were critical of authorities, many of which contained pornographic content.
His work Justine (1791) interlaced orgiastic scenes along with extensive debates on the ills of property and traditional hierarchy in society.
Pornography in the Victorian era
During the Victorian era (1837–1901), the invention of the rotary printing press made publication of books easier, many works of lascivious nature were published during this period often under pen names or anonymity. In 1837, the Holywell Street (known as "Booksellers' Row") in London had more than 50 shops that sold pornographic material. Many of the works published in the Victorian era are considered bold and graphic even by today's lenient standards. The English novel The Adventures, Intrigues, and Amours, of a Lady's Maid! written by anonymous "Herself" (c. 1838) professed the notion that homosexual acts are more pleasurable for women than heterosexuality which is linked to painful and uncomfortable experiences. Some of the popular publications from this era include: The Pearl (magazine of erotic tales and poems published from 1879 to 1881); Gamiani, or Two Nights of Excess (1870) by Alfred de Musset; and Venus in Furs (1870) by Leopold von Sacher-Masoch, from whose name the term "masochism" was derived. The Sins of the Cities of the Plain (1881) is one of the first sole male homosexual literary work published in English, this work is said to have inspired another gay literary work Teleny, or The Reverse of the Medal (1893), whose authorship has often been attributed to Oscar Wilde. The Romance of Lust, written anonymously and published in four volumes during 1873–1876, contained graphical descriptions of themes detailing incest, homosexuality, and orgies. Other publications from the Victorian era that included fetish and taboo themes such as sadomasochism and 'cross-generational sex' are: My Secret Life (1888–1894) and Forbidden Fruit (1898). On accusations of obscenity many of these works had been outlawed until the 1960s.
Criminalization
The English act
The world's first law that criminalized pornography was the English Obscene Publications Act 1857, enacted at the urging of the Society for the Suppression of Vice. The act passed by the British Parliament in 1857 applied to the United Kingdom and Ireland. The act made the sale of obscene material a statutory offense, and gave the authorities the power to seize and destroy any material which they considered as obscene.
For centuries before, sexually explicit material was considered a domain that is exclusive to aristocratic classes. When pornographic material flourished in the Victorian-era England, the affluent classes believed they are sensible enough to deal with it, unlike the lower working classes whom they thought would get distracted by such material and cease to be productive. Beliefs that masturbation would make people ill, insane, or become blind also flourished. The obscenity act gave government officials the power to interfere in the private lives of people unlike any other law before. Some of the people suspected for masturbation were forced to wear chastity devices. "Cures" and "treatment" for masturbation involved such measures like giving electric shock and applying carbolic acid to the clitoris. The law was criticized for being established on still yet unproven claims that sexual material is noxious for people or public health.
The American act
In 1865, the US postal service was seen as a "vehicle" for the transmission of materials that were deemed obscene by the American lawmakers. An act relating to the postal services was passed, which made people pay a fine of $500 for knowingly mailing any "obscene book, pamphlet, picture print, or other publication". From 1865 to up until the first three months of 1872, a total number of nine people were held for various charges of obscenity, with one person sentenced to prison for a year; while in the next ten months fifteen people were arrested under this law. This was partly due to the efforts of Anthony Comstock, who became a major figure in 1872 and held great power to control sexual related activities of people including the choice of abortion.
The Comstock Act of 1873 is the American equivalent of the English Obscene Act. The anti-obscenity bill, drafted by Anthony Comstock, was debated for less than an hour in the US Congress before being passed into law. Apart from the power to seize and destroy any material alleged to be obscene, the law made it possible for the authorities to make arrests over any perceived act of obscenity, which included possession of contraceptives by married couples. Reportedly in the US, 15 tons of books and 4 million pictures were destroyed, and about 15 people were driven to suicide with 4,000 arrests. At least 55 people whom Comstock identified as abortionists got indicted under the Comstock act.
Steps towards liberalization
The laws regarding pornography have differed in various historical, cultural, and national contexts. The English Act did not apply to Scotland where the common law continued to apply. Before the English Act, publication of obscene material was treated as a common law misdemeanor, this made effectively prosecuting authors and publishers difficult even in cases where the material was clearly intended as pornography. However, neither the English, nor the United States Act defined what constituted "obscene", leaving this for the courts to determine. For implementing the Comstock act, the US courts used the British Hicklin test to define obscenity, the definition of which was first proposed in 1868, ten years after the passing of the English obscene act. The definition became cemented in 1896 and continued until the mid-twentieth century. Starting from 1957 to 1997, the US Supreme Court made numerous judgments that redefined obscenity.
The nineteenth-century legislation eventually outlawed the publication, retail and trafficking of certain writings and images that were deemed pornographic. Although laws ordered the destruction of shop and warehouse stock meant for sale, the private possession and viewing of (some forms of) pornography was not made an offense until the twentieth century. Historians have explored the role of pornography in determining social norms. The Victorian attitude that pornography was only for a select few is seen in the wording of the Hicklin test, stemming from a court case in 1868, where it asked: "whether the tendency of the matter charged as obscenity is to deprave and corrupt those whose minds are open to such immoral influences".
Although officially prohibited, the sale of sexual material nevertheless continued through "under the counter" means. Magazines specialising in a genre called "saucy and spicy" became popular during this time (1896 to 1955), titles of few popular magazines include; Wink: A Whirl of Girls, Flirt: A FRESH Magazine, and Snappy. Cover stories in these magazines featured segments such as "perky pin-ups" and "high-heel cuties". Some of the popular erotic literary works from the twentieth century include the novels: Story of the Eye (1928), Tropic of Cancer (1934), Tropic of Capricorn (1938), the French Histoire d'O (Story of O) (1954); and the short stories: Delta of Venus (1977), and Little Birds (1979).
Invention of photography and filmography
After the invention of photography, the birth of erotic photography followed. The oldest surviving image of a pornographic photo is dated back to about 1846, described as to depict "a rather solemn man gingerly inserting his penis into the vagina of an equally solemn and middle-aged woman". At one point of time, it was more expensive to purchase an erotic photograph than to hire a prostitute. The Parisian demimonde included Napoleon III's minister, Charles de Morny, an early patron who delighted in acquiring and displaying erotic photos at large gatherings.
Pornographic film production commenced almost immediately after the invention of the motion picture in 1895. A pioneer of the motion picture camera, Thomas Edison, released various films, including The Kiss that were denounced as obscene in late 19th century America. Two of the earliest pioneers of pornographic films were Eugène Pirou and Albert Kirchner. Kirchner directed the earliest surviving pornographic film for Pirou under the trade name "Léar". The 1896 film, , showed Louise Willy performing a striptease. Pirou's film inspired a genre of risqué French films that showed women disrobing, and other filmmakers realized profits could be made from such films.
Legalization
Sexually explicit films opened producers and distributors to be liable for prosecution. Such films were produced illicitly by amateurs, starting in the 1920s, primarily in France and the United States. Processing the film was risky as was their distribution, which was strictly private. In the Western world, during the 1960s, social attitudes towards sex and pornography slowly changed.
In 1967, Denmark repealed the obscenity laws on literature; this led to a decline in the sale of pornographic and erotic literature. Hoping for a similar effect, in the summer of 1969, legislators in Denmark abolished censorship on picture pornography, thereby effectively becoming, from July 1, 1969, the first country that legalized pornography, including child pornography, which was later prohibited in 1980. The 1969 legislation, instead of resulting in a decline in pornography production, led to an explosion of investment in, and commercial production of pornography in Denmark, which made the country's name synonymous with sex and pornography. The total retail turnover of pornography in Denmark for the year 1969 was estimated at $50 million. Much of the pornographic material produced in Denmark was smuggled into other countries around the world.
In the United States, pornography is protected by the First Amendment to the United States Constitution unless it constitutes obscenity or child pornography that is produced with real children. Nevertheless, in Stanley v. Georgia (1969), the U.S. Supreme Court upheld the right of an adult to possess obscene material in private. Subsequently, however, the Supreme Court rejected the claim that under Stanley there is a constitutional right to provide obscene material for private use or to acquire it for private use. The right to possess obscene material does not imply the right to provide or acquire it, because the right to possess it "reflects no more than ... the law's 'solicitude to protect the privacies of the life within [the home]'".
In 1969, Blue Movie by Andy Warhol became the first feature film to depict explicit sexual intercourse that received a wide public theatrical release in the United States.
Film scholar Linda Williams remarked that prurience "is a key term in any discussion of moving-image sex since the sixties. Often it is the "interest" to which no one wants to own up". In 1968, the Motion Picture Association of America created a new film ratings system in which any film that was not approved by the association was released with an "X" rating. When pornographers began to release their productions with the rating X, the association adopted NC-17 rating for adults only films, leaving the X rating to pornography. Later the invented gimmick rating "XXX" became a standard for pornographic material.
Commissions and their findings
In 1970, the United States President's Commission on Obscenity and Pornography, set up to study the effects of pornography, reported that there was "no evidence to date that exposure to explicit sexual materials plays a significant role in the causation of delinquent or criminal behavior among youths or adults". The report further recommended against placing any restriction on the access of pornography by adults and suggested that legislation "should not seek to interfere with the right of adults who wish to do so to read, obtain, or view explicit sexual materials". Regarding the notion that sexually explicit content is improper, the Commission found it "inappropriate to adjust the level of adult communication to that considered suitable for children". The Supreme Court supported this view.
In 1971, Sweden removed its obscenity clause. Further relaxation of legislations during the early 1970s in the US, West Germany and other countries led to rise in pornography production. The 1970s had been described by Linda Williams as 'the "Classical" Era of Theatrically Exhibited Porn', a time period now called the Golden Age of Porn.
In 1979, the British Committee on Obscenity and Film Censorship better known as the Williams Committee, formed to review the laws concerning obscenity reported that pornography could not be harmful and to think anything else is to see pornography "out of proportion". The committee declared that existing variety of laws in the field should be scrapped and so long as it is prohibited from children, adults should be free to consume pornography as they see fit.
The Meese Report in 1986 argued against loosening restrictions on pornography in the US. The report was criticized as biased, inaccurate, and not credible.
In 1988, the Supreme Court of California ruled in the People v. Freeman case that "filming sexual activity for sale" does not amount to procuring or prostitution and shall be given protection under the first amendment. This ruling effectively legalized the production of X-rated adult content in the Los Angeles county, which by 2005 had emerged as the largest center in the world for the production of pornographic films. Pornographic films appeared throughout the twentieth century. First as stag films (1900–1940s), then as porn loops or short films for peep shows (1960s), followed by as feature films for theatrical release in adult movie theaters (1970s), and as home videos (1980s).
Role of magazines in legalization
Pornographic magazines published during the mid-twentieth century have been noted for playing an important role in the sexual revolution and the liberalization of laws and attitudes towards sexual representation in the Western world. Hugh Hefner, in 1953 published the first US issue of the Playboy, a magazine which as Hefner described is a "handbook for the urban male". The magazine contained images of nude women along with articles and interviews covering politics and culture. Twelve years later, in 1965, Bob Guccione in the UK started his publication Penthouse, and published its first American issue in 1969 as a direct competitor to Playboy. In its early days, the images of naked women published in Playboy did not show any pubic hair or genitals. Penthouse became the first magazine to show pubic hair in 1970. Playboy followed the lead and there ensued a competition between the two magazines over publication of more racy pictures, a contest that eventually got labeled as the "Pubic Wars".
"We were the first to show full frontal nudity. The first to expose the clitoris completely. I think we made a very serious contribution to the liberalization of laws and attitudes. HBO would not have gone as far as it does if it was not for us breaking the barriers. Much that has happened now in the Western world with respect to sexual advances is directly due to steps that we took." — Bob Guccione, Penthouse founder in 2004.
The tussle between Playboy and Penthouse paled into obscurity when Larry Flynt started Hustler, which became the first magazine to publish labial "pink shots" in 1974. Hustler projected itself as the magazine for the working classes as opposed to the urban centered Playboy and Penthouse. During the same time in 1972, Helen Gurley Brown, editor of the Cosmopolitan magazine, published a centerfold that featured actor Burt Reynolds in nude. His popular pose has been later emulated by many other famous people. The success of Cosmo led to the launch of Playgirl in 1973. At their peak, Playboy sold close to six million copies a month in the US, while Penthouse nearly five million. In the 2010s, as the market for printed versions of pornographic magazines declined, with Playboy selling about a million and Penthouse about a hundred thousand, many magazines became online publications. As of 2005, the best-selling US adult magazines maintained greater reach compared to most other non-pornographic magazines, and often ranked among top-sellers.
Modern-day pornography
Modern-day pornography began to take shape from the mid-1980s when the first desktop computers and public computer networks were released.
Since the 1990s, the Internet has made pornography more accessible and culturally visible. Before the 90s, Usenet newsgroups served as the base for what has been called the "amateur revolution" where non-professionals from the late 1980s and early 1990s, with the help of digital cameras and the Internet, created and distributed their own pornographic content independent of mainstream networks. The use of the World Wide Web became popular with the introduction of Netscape navigator in 1994. This development led to newer methods of pornography distribution and consumption. The Internet turned out to be a popular source for pornography and was called the "Triple A-Engine" for offering consumers "anonymity, affordability, and accessibility", while driving the business of pornography. The notion of Internet being a medium abound with porn became popular enough that in 1995 Time published a cover story titled "CYBERPORN" with the face of a shocked child as the cover photo.
In the Reno v. ACLU (1997) ruling, the US Supreme Court upheld the legality of pornography distribution and consumption by adults over the Internet. The Court noted that government may not reduce the communication between adults to "only what is fit for children".
With the introduction of broadband connections, much of the distribution networks of pornography moved online giving consumers anonymous access to a wide range of pornographic material. To have better control over their content on the Internet some professional pornographers maintain their own websites. Danni's Hard Drive started in 1995 by Danni Ashe is considered one of the earliest online pornographic websites, coded by Ashe – a former stripper and nude model, the website was reported by CNN to had generated revenues of $6.5 million by 2000. According to some leading pornography providers on the Internet, customer subscription rates for a website would be about one in a thousand people who visit the site for a monthly fees averaging around $20. Ashe said in an interview that her website employs 45 people and she expects to earn $8 million in 2001 alone. The total number of pornographic websites in 2000 were estimated to be more than 60,000. The development of streaming sites, peer-to-peer file sharing (P2P) networks, and tube sites led to a subsequent decline in the sale of DVDs and adult magazines.
Starting in the 21st century, greater access to the Internet and affordable smartphones made pornography more accessible and culturally mainstream. The total number of pornographic websites in 2012 was estimated to be around 25 million comprising 12% of all the websites. About 75 percent of households in the US gained Internet access by 2012. Data from 2015 suggests an increase in pornography consumption over the past few decades which is attributed to the growth of Internet pornography. Technological advancements such as digital cameras, laptops, smartphones, and Wi-Fi have democratized the production and consumption of pornography. Subscription-based service providers such as OnlyFans, founded in 2016, are becoming popular as the platforms for pornography trade in the digital era. Apart from the professional pornographers, content creators on such platforms include others like; a physics teacher, a race car driver, a woman undergoing cancer treatment. In 2022, the total pornographic content accessible online was estimated to be over 10,000 terabytes.
AVN and XBIZ are the industry-specific organizations based in the US that provide information about the adult entertainment business. XBIZ Awards and AVN Awards, analogous to the Golden globes and Oscars, are the two prominent award shows of the adult entertainment industry. Free Speech Coalition (FSC) is a trade association and Adult Performer Advocacy Committee (APAC) is a labor union for the adult entertainment industry based in the US. The scholarly study of pornography notably in cultural studies is limited. Porn Studies, which began in 2014, is the first international peer-reviewed, academic journal that is exclusively dedicated to the critical study of the "products and services" identified to constitute pornography.
Classifications
Adult content classifications
Adult content is generally classified as either pornography or erotica. Considerations of distinctness between pornography and erotica is mostly subjective. Pornographic content is categorized as softcore or hardcore. Softcore pornography contains depictions of nudity but without explicit depiction of sexual activity. Hardcore pornography includes explicit depiction of sexual activity. Hardcore porn is more regulated than softcore porn. Softcore porn was popular between the 1970s and 1990s.
Mainstream pornography
Pornography productions cater to consumers of various sexual orientations. Nonetheless, pornography featuring heterosexual acts made for heterosexual consumers, comprise the bulk of what is called the "mainstream porn", marking the industry more or less as "heteronormative".
Mainstream pornography involves professional performers who work for various corporate film studios in their respective productions.
Mainstream pornography productions are usually classified as feature or gonzo. Features involve storylines, characterizations, scripted dialog, elegant costumes, detailed sets, and soundtracks, which make the productions look similar to mainstream Hollywood productions but with the depictions of explicit sexual activity included. Features contain both original narratives as well as parodies that parody mainstream feature films, TV shows, celebrities, video games or literary works. Gonzo is a form of content creation that attempts to put the viewer into the scene, this is commonly achieved by close-up camera work or performers talking to the audience; also called "wall-to-wall", gonzo involves some aspects of "breaking the fourth wall" between the audience and performers. The term "gonzo" is often misused as a genre to identify demeaning depictions, however gonzo is a film-making style and not a genre. Gonzo style is variably incorporated in the creation of all types or genres of adult content. Gonzos do not involve the expensive sets or the costly production values of features, which makes their production relatively inexpensive. From the mid-2010s about 95 percent of porn productions are gonzo.
Indie pornography
Pornography productions that are independent of mainstream pornographic studios are classified as indie (or) independent pornography. These productions cater to more specific audience, and often feature different scenarios and sexual activity compared to the mainstream porn. The performers in indie porn include real-life couples and regular people, who sometimes work in partnership with other performers. Apart from content creation the performers do the background work such as videography, editing, web development themselves, and distribute under their own brand. Paysites like Clips4Sale.com, MakeLoveNotPorn.tv, and PinkLabel.tv provide a platform to the web-based content of independent pornographers.
Genres
Pornography encompasses a wide variety of genres providing for an enormous range of consumer tastes. Most of the genres or types are named according to the depiction of sexual activity, these include: anal, creampie, cum shot, double penetration, fisting, threesome. Categorizations based on the age of the performers include: teens, milf, mature. Other categorizations based on gender and sexual identity include: lesbian, transsexual, queer, shemale; while those based on race include: ethnic, interracial. Others include: Mormon, zombie. Pornography also features numerous fetishes like: "'fat' porn, amateur porn, disabled porn, porn produced by women, queer porn, BDSM and body modification."
Commercialism
Pornography is commercialized mainly through the sale of pornographic films. Many adult films had theatrical releases during the 1970s corresponding with the Golden Age of Porn. A 1970 federal study estimated that the total retail value of hardcore pornography in the United States was no more than $5 million to $10 million.
The release of the VCR by Sony Corporation for the mass market in 1975 marked the shift of people from watching porn in adult movie theaters, to the confines of their houses. The introduction of VHS brought down the production quality through the 1980s.
Starting in the 1990s, Internet eased the access to pornography. The pay-per-view model enabled people to buy adult content directly from cable and satellite TV service providers. According to Showtime Television network report, in 1999 adult pay-per-view services made $367 million, which was six times more than the $54 million earned in 1993. Although this development resulted in a decline in rentals, the revenues generated over the Internet, provided much financial gains for pornography producers and credit card companies among others. By the mid-1990s, the adult film industry had agents for performers, production teams, distributors, advertisers, industry magazines, and trade associations. The introduction of home video and the World Wide Web in the late twentieth century led to global growth in the pornography business. Performers got multi-film contracts. In 1998, Forrester Research reported that online "adult content" industry's estimated annual revenue is at $750 million to $1 billion.
Retail stores or sex shops engaged in the sale of adult entertainment material ranging from videos, magazines, sex toys and other products, significantly contributed to the overall commercialization of pornography. Sex shops sell their products on both online shopping platforms such as Amazon and on specialized websites.
In 2000, the total annual revenue from the sales and rentals of pornographic material in the US was estimated to be over $4 billion. The hotel industry through the sale of adult movies to their customers as part of room service, over pay-per-view channels, had generated an annual income of about $180-$190 million. Some of the major companies and hotel chains that were involved in the sale of adult films over pay-per-view platforms include; AT&T, Time Warner, DirecTV from General Motors, EchoStar, Liberty Media, Marriott International, Westin and Hilton Worldwide. The companies said their services are in response to a growing American market that wanted pornography delivered at home.
Studies in 2001 had put the total US annual revenue (including video, pay-per-view, Internet and magazines) between $2.6 billion and $3.9 billion.
Economics
The production and distribution of pornography are economic activities of some importance. In Europe, Budapest is regarded as the industry center. Other pornography production centers in the world are located in Florida (US), Brazil, Czech Republic, and Japan. In the United States, the pornography industry employs about 20,000 people including 2,000 to 3,000 performers, and is centered in the San Fernando Valley of Los Angeles. By 2005, it became the largest pornography production center in the world. Apart from regular media coverage, the industry in the US receives considerable attention from private organizations, government agencies, and political organizations.
As of 2011, pornography was becoming one of the biggest businesses in the United States. In 2014, the porn industry was believed to bring in at least $13 billion on a yearly basis in the United States. Through the 2010s, many pornography production companies and top pornographic websites such as Pornhub, RedTube and YouPorn have been acquired by MindGeek, a company that has been described as "a monopoly" in the pornography business. This development was identified as a problem. According to Marina Adshade, a professor from the Vancouver School of Economics and the author of Dollars and Sex: How economics influences sex and love, having a monopoly in the pornography business has forced the producers to reduce their charges, and radically changed the work of performers "who are now under greater pressure to perform acts that they would have been able to refuse in the past", all at a lower price without profits for themselves.
Online pornography is available both for a fee and free of charge. The availability of free porn on the Internet has led to a decline in the business of mainstream pornography. Piracy is estimated to result in losses of some $2 billion a year for the porn industry. Budgets of many studios reduced considerably and contracts for performers became less common. Reportedly, applications by established pornography companies for porn-shoot permits in Los Angeles County fell by 95 percent during the period 2012 to 2015. According to Mark Spiegler, an adult talent agent, in the early 2000s female performers made about $100,000 a year. By 2017, the amount is about $50,000.
The technological era led to decline of the studio and "the rise of the pornography worker herself". Newer ways of monetization have opened for the pornography workers who are taking the path of entrepreneurship. In 1995, Jenna Jameson signed her first contract with the porn studio Wicked Pictures. After building a brand image for herself she started her own company ClubJenna, which by 2005 was reportedly earning an annual revenue of $30-$35 million. "Performers are hustlers now," said Chanel Preston (a performer who was also chairperson of the Adult Performer Advocacy Committee), while noting that performers have to be creative to sustain their income and reach audience, both of which, she said are mainly achieved through "feature dancing, selling merchandise, webcamming", among other activities. "Custom" pornography made according to the requests of customer clients has emerged as one new business niche. The average career for the new age performer lasts about four to six months. Before moving on to the business side, adult performers use studio works to advertise and build a brand image for themselves. They acquire an audience who would later pay at personal website or webcam performances. Commercial webcamming, which emerged in the 1990s as a niche sector in the adult entertainment industry, grew to become a multibillion-dollar business by the mid-2020s.
The exact economic size of the porn industry in the early-twenty-first century is unknown to anyone. Kassia Wosick, a sociologist from New Mexico State University, estimated the global porn market value at $97 billion in 2015, with the US revenue estimated at $10 and $12 billion. IBISWorld, a leading researcher of various markets and industries, calculated total US revenue to reach $3.3 billion by 2020. On the basis of a research report by a market analysis firm, USA Today published that the estimated worth of the adult entertainment industry market in 2023 is over $172 billion.
Technology
Pornographers have taken advantage of each major technological advancement for the production and distribution of their services. Pornography has been called an "erotic engine" and a driving force in the development of various media related technologies from the printing press, through photography (still and motion), to satellite TV, Home video, and streaming media.
One of the world's leading anti-pornography campaigners, Gail Dines, has stated that "the demand for porn has driven the development of core cross-platform technologies for data compression, search, transmission and micro-payments." Many of the technological developments that had been led by pornography have benefited other fields of human activity too. In the early 2000s, Wicked Pictures pushed for the adoption of the MPEG-4 file format ahead of others, this later became the most commonly used format across high-speed Internet connections. In 2009, Pink Visual became one of the first companies to license and produce content with a software introduced by a small Toronto-based company called "Spatial view", which later made it possible to view 3D content on iPhones.
As an early adopter of innovations, the pornography industry has been cited to be a crucial factor in the development and popularization of various media processing and communication technologies. From innovative smaller film cameras, to the VCRs, and the Internet, the porn industry has employed newer technologies much ahead than other commercial industries, this early adoption provided the developers their early financial capital, which aided in the further development of these technologies. The success of innovative technologies is predicted by their greater use in the porn industry.
Pornographic content accounted for most videotape sales during the late 1970s. The pornography industry has been considered an influential factor in deciding the format wars in media, including being a factor in the VHS vs. Betamax format war (the videotape format war) and the Blu-ray vs. HD DVD format war (the high-def format war). Piracy, the illegal copying and distribution of material, is of great concern to the porn industry. The industry has been the subject of many litigations and formalized anti-piracy efforts.
Many of the innovative data rendering procedures, enhanced payment systems, customer service models, and security methods developed by pornography companies have been co-opted by other mainstream businesses. Pornography companies served as the basis for a large number of innovations in web development. Much of the IT work in porn companies is done by people who are referred to as a "porn webmaster", often paid well in what are small businesses, they have more freedom to test innovations compared to other IT employees in larger organizations who tend to be risk-averse.
Virtual reality pornography
Some pornography is produced without human actors at all. The idea of computer-generated pornography was conceived very early as one of the obvious areas of application for computer graphics. Until the late 1990s, digitally manipulated pornography could not be produced cost-effectively. In the early 2000s, it became a growing segment as the modeling and animation software matured, and the rendering capabilities of computers improved. Further advances in technology allowed increasingly photorealistic 3D figures to be used in interactive pornography. The first pornographic film to be shot in 3D was 3D Sex and Zen: Extreme Ecstasy, released on 14 April 2011, in Hong Kong.
The various mediums for pornography depictions have evolved throughout the course of history, starting from prehistoric cave paintings, about forty millennia ago, to futuristic virtual reality renditions. Experts in the pornography business predict more people in the future would consume porn through virtual reality headsets, which are expected to give consumers better personal experiences than they can have in the real world. Speculations are rife about an increased presence of sex robots in the future pornography productions.
Consumption
Pornography is a product made by adults-for the consumption by adults, the consumption of which has become more common among people due to the expansive use of the Internet. About 90% of pornography is consumed on the Internet with consumers preferring content that is in tune with their sexuality. Pornography has been found to be a significant influencer of people's ideas about sex in the digital age. Pornographic websites rank among the top 50 most visited websites worldwide. XVideos and Pornhub are the two most visited pornographic websites worldwide.
Pornography consumption in people is found to induce "psychological moods and emotions" similar to those evoked during actual sexual intercourse and casual sex. Researchers identified four broad motivating factors for pornography consumption: an innate sexual drive or desire, to learn about sex and improve ones own sexual performance, peer pressure or social groups, lack of sexual relationship or absence of partner. Majority of pornography consumers tend to be male, unmarried, with higher levels of education. Younger people are more frequent consumers of porn than older people. There's been a gradual increase in the consumption rates across different age groups with the increased availability of free porn over the Internet.
Researchers at McGill University ascertained that on viewing pornographic content, men reached their maximum arousal in about 11 minutes and women in about 12 minutes. An average visit to a pornographic website lasts for 11.6 minutes. Both marriage and divorce are found to be associated with lower subscription rates for adult entertainment websites. Subscriptions are more widespread in regions that have higher measures of social capital. Pornographic websites are most often visited during office hours. As per a recent CNBC report, seventy per cent of online-porn access in the US happens between nine-to-five hours.
Sexual arousal and sexual enhancement tend to be the primary motivations among the self-reported reasons by users for their pornography consumption.
Studies had found that greater levels of psychological distress leads to higher rates of pornography consumption. Pornography may provide a temporary relief from stress, or anxiety. A need to assuage coping and boredom is also found to result in higher consumption of pornography.
By Gender
A study of Austrian adults found that men consume pornography more frequently than women. The intent for consumption may vary, with men being more likely to use pornography as a stimulant for sexual arousal during solitary sexual activity, while women are more likely to use pornography as a source of information or entertainment, and rather prefer using it together with a partner to enhance sexual stimulation during partnered sexual activity. Studies have found that sexual functioning defined as "a person's ability to respond sexually or to experience sexual pleasure" is greater in women who consume pornography frequently than in women who do not. No such association was noticed in men. Women who consume pornography are more likely to know about their own sexual interests and desires, and in turn be willing and able to communicate them during partnered sexual activity, it has been reported that in women the ability to communicate their sexual preferences is associated with greater sexual satisfaction for themselves. Pornographic material is found to expand the sexual repertoire in women by making them learn new rewarding sexual behaviors such as clitoral stimulation and enhance their overall "sexual flexibility". Women who consume pornography frequently are more easily aroused during partnered sex and are more likely to engage in oral sex compared to the women who do not view pornography. Women users of pornography had reported (almost 50%) to have had engaged in cunnilingus, which research suggests is related to female orgasm, and to have had experienced orgasms more frequently than women who do not use pornography (87% vs. 64%). Most people, probably do not consider pornography use by a partner as indulging in infidelity.
By education level
A two year long survey (2018–2020) conducted to assess the role of pornography in the lives of highly educated medical university students, with median age of 24, in Germany found that pornography served as an inspiration for many students in their sex life. Pornography use among students was higher in males than in females, among the male students those who did not cheat on their partner or contracted an STI were found to be more frequent consumers of pornography. Although pornography use was more common among men, associations between pornography use and sexuality were more apparent in women. Among the female students, those who reported to be satisfied with their physical appearance have consumed three times as much pornography than the female students who had reported to be dissatisfied with their body. A feeling of physical inadequacy was found to be a restraining factor in the consumption of pornography. Female students who consume pornography more often had reported to have had multiple sexual partners. Both female and male students who enjoyed the experience of anal intercourse in their life were reported to be frequent consumers of pornography. Sexual content depicting bondage, domination, or violence was consumed by only a minority of 10%. More sexual openness and less sexual anxiety was observed in students who regularly consumed pornography. No association was noticed between regular pornography use and experience of sexual dissatisfaction in either female or male students. This finding was in concurrence with another finding from a longitudinal study, which demonstrated most pornography consumers differentiate pornographic sex from real partnered sex and do not experience diminishing satisfaction with their sex life.
By region
A vast majority of men and considerable number of women in the US use porn. A study in 2008 found that among University students aged 18 to 26 located in six college sites across the United States, 67% of young men and 49% of young women approved pornography viewing, with nearly 9 out of 10 men (87%) and 31% women reportedly using pornography. The Huffington Post reported in 2013 that porn websites registered higher number of visitors than Netflix, Amazon, and Twitter combined. A 2014 poll, which asked Americans when they had "last intentionally looked at pornography", elicited a result that 46% of men and 16% of women in the age group of 18–39 did so in the past week. A 2016 study reported that about 70% of men and 34% of women in romantic relationships use pornography annually. Gallup poll surveys conducted over the years 2011 to 2018 noted a gradual increase in the acceptance rates of pornography among the general American public.
Since the late 1960s, attitudes towards pornography have become more positive in Nordic countries; in Sweden and Finland the consumption of pornography has increased over the years. A 2006 study of Norwegian adults found that over 80% of the respondents used pornography at some point in their lives, a difference of 20% was observed between men and women in their respective use. A 2015 study in Finland noted that 75% of the 30-40-y.o. women and above 90% of the 30-40-y.o. men found porn "very exciting". Of those who had watched porn during the latest year, 71% of the 18-24-y.o. women, almost 60% of the 18-49-y.o. women, and a tenth of 65+ women did so; among men, the numbers were above 90% of the men under 50-y.o., 3/4 of the 18-64-y.o. and most of the 65+ y.o.; the numbers were quickly increasing, particularly for women, partially due to increased masturbation.
In 2012 and 2013, interviews with large number of Australians revealed that in the past year 63% of men and 20% of women had viewed pornography.
A 2020 Egyptian study surveying 15,027 individuals in Arab countries noted a prevalence of pornography use "nearly similar to Danish, German, and American ones".
In 2021, it was estimated that in modern countries, 46–74% of men and 16–41% of women are regular users of pornography. In 2022, a national survey in Japan, of men and women aged 20 to 69 revealed that 76% of men and 29% of women had used pornography as part of their sexual activity. A 2023 study reported that in Netherlands, young men who watched porn in the previous six months ranged between 65% (13–15-y.o.) to 96% (22–24-y.o.), and among young women between 22% (13–15-y.o.) to 75% (22–24-y.o.).
Legality and regulations
The legal status of pornography varies widely from country to country. Regulating hardcore pornography is more common than regulating softcore pornography. Child pornography is illegal in almost all countries, and some countries have restrictions on rape pornography and zoophilic pornography.
Pornography in the United States is legal provided it does not depict minors, and is not obscene. The community standards, as indicated in the Supreme Court decision, of the 1973 Miller v. California case determine what constitutes as "obscene". The US courts do not have jurisdiction over content produced in other countries, but anyone distributing it in the US is liable to prosecution under the same community standards. As the courts consider community standards foremost in deciding any obscenity charge, the changing nature of community standards over the course of time and place makes instances of prosecution limited.
In the United States, a person receiving unwanted commercial mail that he or she deems pornographic (or otherwise offensive) may obtain a Prohibitory Order. Many online sites require the user to tell the website they are a certain age and no other age verification is required. A total of 16 states and the Republican Party have passed resolutions declaring pornography a "public health" threat. These resolutions are symbolic and do not put any restrictions but are made to sway the public opinion on pornography. The notion of pornography as a threat to public health is not supported by any international health organization.
The adult film industry regulations in California requires that all performers in pornographic films use condoms. However, the use of condoms in pornography is rare. As porn does better financially when actors are without condoms many companies film in other states. Twitter is the popular social media platform used by the performers in porn industry as it does not censor content unlike Instagram and Facebook.
Pornography in Canada, as in the US, criminalizes the "production, distribution, or possession" of materials that are deemed obscene. Obscenity, in the Canadian context, is defined as "the undue exploitation of sex" provided it is connected to images of "crime, horror, cruelty, or violence". As to what is considered "undue" is decided by the courts, which assess the community standards in deciding whether exposure to the given material may result in any harm, with harm defined as "predisposing people to act in an anti-social manner".
Pornography in the United Kingdom does not have the concept of community standards. Following the highly publicized murder of Jane Longhurst, the UK government in 2009 criminalized the possession of what it terms as "extreme pornography". The courts decide whether any material is legally extreme or not, conviction for penalty include fines or incarceration up to three years. Content banned includes representations that are considered "grossly offensive, disgusting, or otherwise of an obscene character".
While there are no restrictions on depiction of male ejaculation, any depiction of female ejaculation in pornography is completely banned in the UK, as well as in Australia.
In most of Southeast Asia, Middle East, and China, the production, distribution, and/or possession of pornography is illegal and outlawed. In Russia and Ukraine, webcam modeling is allowed provided it contains no explicit performances; in other parts of the world commercial webcamming is banned as a form of pornography.
Disseminating pornography to a minor is generally illegal. There are various measures to restrict minors' any access to pornography, including protocols for pornographic stores.
Pornography can infringe into basic human rights of those involved, especially when sexual consent was not obtained. Revenge porn is a phenomenon where disgruntled sexual partners release images or video footage of intimate sexual activity of their partners, usually on the Internet, without authorization or consent of the individuals involved. In many countries there has been a demand to make such activities specifically illegal carrying higher punishments than mere breach of privacy, or image rights, or circulation of prurient material. As a result, some jurisdictions have enacted specific laws against "revenge porn".
What is not pornography
In the US, a July 2014 criminal case decision in Massachusetts Commonwealth v. Rex, 469 Mass. 36 (2014), made a legal determination as to what was not to be considered "pornography" and in this particular case "child pornography". It was determined that photographs of naked children that were from sources such as National Geographic magazine, a sociology textbook, and a nudist catalog were not considered pornography in Massachusetts even while in the possession of a convicted and (at the time) incarcerated sex offender.
Drawing the line depends on time, place and context. Occidental mainstream culture has been increasingly getting "pornified" (i.e. influenced by pornographic themes, with mainstream films often including unsimulated sexual acts). Since the very definition of pornography is subjective, material that is considered erotic or even religious in one society may be denounced as pornography in another. When European travellers visited India in the 19th century, they were dismayed at the religious representation of sexuality on the Hindu temples and deemed them as pornographic. Similarly many films and television programs that are unobjectionable in contemporary Western societies are labeled as "pornography" in Muslim societies. Thus, assessing a material as pornography is very much personalized; to rehash a cliché, "pornography is very much in the eye of the beholder".
Copyright status
In the United States, some courts have applied US copyright protection to pornographic materials. Some courts have held that copyright protection effectively applies to works, whether they are obscene or not, but not all courts have ruled the same way. The copyright protection rights of pornography in the United States has again been challenged as late as February 2012.
STIs prevention and safer sex practices
Performers working for pornographic film studios undergo regular testing for sexually transmitted infections (STIs) every two weeks. They have to test negative for: HIV, trichomoniasis, chlamydia, gonorrhea, syphilis, and hepatitis B and C before showing up on a set and are then inspected for sores on their mouths, hands, and genitals before commencing work. The industry believes this method of testing to be a viable practice for safer sex as its medical consultants claim that since 2004, about 350,000 pornographic scenes have been filmed without condoms and HIV has not been transmitted even once because of performance on set. However, some studies suggest that adult film performers have high rates of chlamydia and/or gonorrhea infection, and many of these cases may be missed by industry screening because these bacteria can colonize many sites on the body.
In the initial years, studios assessed performers suitability on the results from their blood and urine tests. According to a 2019 study by the American College of Emergency Physicians, swab tests offer better insight than urine samples for detecting bacterial STIs like chlamydia and gonorrhea. Performers such as Cherie DeVille have emphasized swab tests for safer sex. According to performer Angela White, studios will not allow them to work unless they are completely clean, she said "So for me, because I work so much, I’m testing every 12 days – and that is a full sweep of STIs such as chlamydia, gonorrhoea, syphilis, HIV and trichomoniasis. We’re doing throat swabs, vaginal swabs and anal swabs." Allan Ronald, a Canadian doctor and HIV/AIDS specialist who did groundbreaking studies on the transmission of STIs among prostitutes in Africa, said there's no doubt about the efficiency of the testing method, but he felt a little uncomfortable: "because it's giving the wrong message — that you can have multiple sex partners without condoms — but I can't say it doesn't work."
Relatedly, it has been found that individuals who received little sex education and/or perceive pornography as a source of information about sex, are less apt to use condoms in their own sex life, making themselves more susceptible to contract STIs. In 2020—the US National Sex Education Standards—released recommendations to incorporate "porn literacy" to students from grade 6 to 12 as part of sex education in the US.
Veteran performer and former nurse Nina Hartley, who has a degree in nursing, stated that the amount of time involved in shooting a scene can be very long, and with condoms in place it becomes a painful proposition as their usage is uncomfortable despite the use of lube, causes friction burn, and opens up lesions in the genital mucosa. Advocating the testing method for performers, Hartley said, "Testing works for us, and condoms work for outsiders."
"We're tested every fourteen days. That is literally twenty-three more times than the average American. If that person makes it to their yearly physical. I have met tons of people that haven't been to the doctor in years. That scares me because they have no idea what their status is.... I don't hook up with people outside of the porn industry because I'm terrified. And I'm not the only one. There's many performers that know: if you go out into the wild, you will come back with something." — Ash Hollywood (Porn actress).
Emphasizing that performers in the industry take necessary precautions like PrEP and are at lower risk to contract HIV than most sexually active persons outside the industry, many prominent female performers have vehemently opposed regulatory measures like Measure B that sought to make the use of condoms mandatory in pornographic films. Professional female performers have called the use of condoms on a daily basis at work an occupational hazard as they cause micro-tears, friction burn, swelling, and yeast infections, which altogether, they say, makes them more susceptible to contract STIs.
Views on pornography
Pornography has been vouched to provide a safe outlet for sexual desires that may not be satisfied within relationships and be a facilitator of sexual fulfillment in people who cannot or do not want to have real-life partners. Pornography is viewed by people in general for various reasons; varying from a need to enrich their sexual arousal, to facilitate orgasm, as an aid for masturbation, learn about sexual techniques, reduce stress, alleviate boredom, enjoy themselves, see representation of people like themselves, know their sexual orientation, improve their romantic relationships, or simply because their partner wants them to.
Pornography is noted for engrossing people "on more than masturbatory levels". Aesthetic philosophers argue whether pornographic representations can be considered as expressions of art.
Pornography has been equated with journalism as both offer a view into the unknown or the hidden aspects. French philosopher Michel Foucault remarked that, "it is in pornography that we find information about the hidden, the forbidden and the taboo".
Scholars such as Linda Williams, Jennifer Nash, and Tim Dean believe pornography "is a form of thinking", comprised with ideas that are way more reflective about sexuality and gender than what the creators or consumers of pornography intend. Pornography has been referred by people as a means to explore their sexuality. People have reported porn being helpful in learning about human sexuality in general. Studies recommend clinical practitioners to use pornography as an instruction aid to show their clients new and alternative sexual behaviors as part of psychosexual therapy. British psychologist, Oliver James, known for his work on 'happiness', stated that "a high proportion of men use porn as a distraction or to reduce stress ... It serves an anti-depressant purpose for the unhappy."
Feminist outlook
Overall
Feminist movements in the late 1970s and 1980s dealt with the issues of pornography and sexuality in debates that are referred to as the "sex wars". While some feminist groups seek to abolish pornography believing it to be harmful, other feminist groups oppose censorship efforts insisting it is benign. A large scale study of data from the General Social Survey (2010–2018) refuted the argument that pornography is inherently anti-woman or anti-feminist and that it drives sexism. The study did not find a relationship between "pornography viewing" and "pornography tolerance" with higher sexism—a posit that was held by some feminists; it instead found higher pornography consumption and pornography tolerance among men to be associated with their greater support for gender equality. The study concluded that "pornography is more likely to be about the sex rather than the sexism".
People who supported regulated pornography expressed lesser attitudes of sexism than people who sought to abolish pornography. Notably, non-feminists are found more likely to support a ban on pornography than feminists. Many feminists, both male and female, have reflected that the effects of pornography on society are neutral. Adult users of pornography were found more egalitarian than nonusers, they are more likely to hold favorable attitudes towards women in positions of power and in workplaces outside home than the nonusers.
Critical
A 2016 study authored by Black feminists criticized the American adult entertainment industry for alleged omission and exclusion of Black women in pornographic representations, particularly in the interracial genres. As pornography becomes a kind of manual on how bodies in pleasure can look, and is "one of the few places where we see our bodies--and other people's bodies," it becomes imperative on pornography to represent "variety of forms", stated the feminist scholars. Anti-pornography feminists argue that aesthetics of pornography demote Black women with undertones of racism. Gender studies scholars Mireille Miller-Young and Jennifer Christine Nash, in their writings on intersectionality of race and pornography, noted that Black people have been depicted as being hypersexual and Black women—more objectified. The scholars also noted major discrepancies in pay rates of the performers, White women have historically made 75 percent more per scene and sometimes still make 50 percent more compared to Black women.
Feminist resentment about pornography tend to focus on two concerns: that pornography depicts violence and aggression, and that pornography objectifies women. Multiple analyses of pornographic videos found that Women have been overwhelmingly at the receiving end of aggression from male performers; with the reaction of Women being either positive or neutral towards aggression, which is at odds considering a report that found only 14.2% of US adult women find pain during sex as appealing. Two studies in the 1990s found that Black women were the targets of aggression and faced more violence from both Black and White men than did White women. However, more recent research from 2018 found that Black women were the least likely group of women to suffer nonconsensual aggression and are more likely to receive affection from their male partners. While Black men engaged in fewer intimate behaviors than White men; White women were found more likely to experience violence during sexual activity with White men than with Black men.
Concerning Asian women, a 2016 study based on a sample of 3053 videos from Xvideos.com, found that in the 170 videos of the Asian women category, there was much less aggression, less objectification, but also the women had less agency. However, another study found that in a sample of 172 videos from Pornhub, the 25+ videos of the Asian/Japanese category had considerably more aggression than those of other categories. A 2002 study of "internet rape sites" found that among the 56 clear pictures they found, 34 had Asian women, and nearly half the sites had either an image or a text reference to an Asian woman. Findings on depictions of Asian women in pornography aren't consistent in scientific literature.
The prevalence of aggression in pornography appears to be changing. A 2018 study of popular videos on Pornhub found that segments of aggression towards women are fewer now, and they have reduced gradually over the past decade with viewers preferring content where women genuinely experience pleasure.
Anti-porn
Prominent anti-pornography feminists such as Andrea Dworkin and Catharine MacKinnon argue that all pornography is demeaning to women, or that it contributes to violence against women–both in its production and in its consumption. The production of pornography, they argue, entails the physical, psychological, or economic coercion of the women who perform in it. They charged that pornography eroticizes the domination, humiliation, and coercion of women, while reinforcing sexual and cultural attitudes that are complicit in rape and sexual harassment.
Other sex work exclusionary feminists have insisted that pornography presents a severely distorted image of sexual consent, and it reinforces sexual myths like: women are readily available–and desire to engage in sex at any time–with any man–on men's terms–and always respond positively to men's advances.
Pro-porn
In contrast to the objections, other feminist scholars "ranging from Betty Friedan and Kate Millett to Karen DeCrow, Wendy Kaminer and Jamaica Kincaid" have supported the right to consume pornography.
The anti-porn feminist stranglehold began to loose when sex-positive feminists like Susie Bright, performers Nina Hartley, and Candida Royalle affirmed the rights of women to consume and produce porn.
The works of Camille Paglia established that westerners have been "pagan celebrants" for long and pornography has been an inseparable part of western culture. Wendy McElroy has noted that both feminism and pornography are mutually related, with both thriving in environments of tolerance, and both repressed anytime regulations are placed on sexual expression.
Societies where pornography and sexual expression is prohibited are more likely to be the places where women are often subjected to violence and sexual abuse.
Rise of feminist porn
The lesbian feminist movement of the 1980s is considered a seminal moment for the women in the porn industry as more women entered into the developmental side. This allowed women to gear porn more towards women as they knew what women wanted, both from the perspective of actresses as well as the female audience. The movement also sparked the arrival of making lesbian porn for lesbians instead of men. This change has been considered good, as for a long time the porn industry had been directed by men for men.
Furthermore, the advent of the VCR, Home video, and affordable Video cameras allowed for the possibility of feminist pornography. Feminist porn directors are interested in challenging representations of men and women, as well as in providing sexually-empowering imagery that features many kinds of bodies. Angela White started her own production company, AWG Entertainment, in which she has complete creative control over the content—from her partners, to the location, costumes, and the "vibe" of the video. "I am a feminist, so what I create is feminist, and I produce ethical porn, which is when everything is consensual." she said.
Women are more likely to consume porn that is "female-centered" and feature acts such as cunnilingus, a study of pornographic videos found that when men spend more time performing cunnilingus they have higher volumes of ejaculate, an increase in sexual arousal resulting from exposure to the vaginal secretion 'copulins' during cunnilingus is reasoned to be the cause. Female-centric porn is mostly made by women, in these works the initiation of sexual activity is done by the female. Porn for women is identified by factors like greater attention to "sensual surroundings" and "soft focus camerawork" rather than on explicit depiction of sexual activity, making the productions more warm and humane compared to the traditional porn made for hetrosexual men.
"If feminists define pornography, per se, as the enemy, the result will be to make a lot of women ashamed of their sexual feelings and afraid to be honest about them. And the last thing women need is more sexual shame, guilt, and hypocrisy—this time served up by feminism" — Ellen Willis.
Pay rates
Porn industry has been noted for being one of the few industries where women enjoy a power advantage in the workplace. "Actresses have the power," Alec Metro, one of the men in line, ruefully noticed of the X-rated industry. A former firefighter who claimed to have lost a bid for a job to affirmative action, Metro was already divining that porn might not be the ideal career choice for escaping the forces of what he called "reverse discrimination". Female performers can often dictate which male actors they will and will not work with. Porn—at least, porn produced for a heterosexual audience—is one of the few contemporary occupations where the pay gap operates in the favor of women. The average actress makes fifty to a hundred per cent more money than her male counterpart.
Psychological perspective
Psychologists consider pornography to be of particular relevance in the study of intimate relationships and the development of adolescent sexuality. Mainstream psychology is mostly concerned with the study of effects of pornography, while critical psychology and applied psychology is engaged in more nuanced and academic study of pornography. Problematic pornography use is assessed in clinical psychology.
A 2013 study refuted the notion that porn actresses have higher rates of psychological problems than regular women. The study compared 177 porn actresses with regular women of similar age, ethnicity, and marital status, and found that the porn actresses had "higher levels of self-esteem, positive feelings, social support, sexual satisfaction, and spirituality" compared to the regular women.
Psychoanalyst views
In analytical psychology, human sexual instincts and religious-spiritual instincts are considered tightly associated with each other, with both sharing a common instinctual objective, which, as Carl Jung acknowledged, is the striving of the psyche for "wholeness". The psyche of a person is understood to be differentiated, as being made-up of psychological traits that are feminine and masculine in nature. According to Jung, this differentiation allowed the formation of opposite polarities, which made "consciousness possible". According to psychologist and author Giorgio Tricarico, as an individual moves through various life experiences, their psyche approaches wholeness or the state of "non-differentiated"—a realm of unified, impersonal consciousness—considered belonging to the sacred or divine. In Hindu cosmological view, the universe is weaved from the two coexisting generative principles: feminine and masculine. Men and women, in whatever form they appear, are considered microcosmic representatives, or mirrors of the macrocosmic energies of Shiva and Shakti. The Goddess or Shakti (spirit, feminine principle) is the "pure consciousness", the animating energy or power underlying existence. Shakti, embraced by Shiva (matter, masculine principle), both together in "perpetual union" form the nondual "Absolute".
Shiva and Shakti in a state of "copulation" represent the flow of "erotic energy" in an individual. Sigmund Freud called the feminine Shakti "libido that cannot be simply repressed." Self-realization or becoming aware of the " 'deep' femininity" entails dealing with the powerful sexual energy. Schools of religious thought such as the Kundalini yoga and Tantra, which involve using the sexual energy for purpose of self-realization had been developed in India. The concept of gender had been studied in Hinduism for long, where the conclusion was arrived that the human self (Ātman), an emanation from the nondual Absolute—is androgynous, and is encased in human bodies, which themselves are androgyne in the sense that every body is a compound of the feminine (spirit) and the masculine (matter) principles. Sexuality is considered a creative function of nature to align the two principles with the nondual Absolute. The masculine and the feminine principles of the self have been identified to the deities Shiva and Shakti, who make-up the two sexual polarities; by establishing a connection between the two, for the flow of erotic energy (as in the case of an electric circuit between positive and negative terminals for the flow of electric current), in one's own being—by the means of sexual stimulation—through "erotic visualization" or "ritual copulation", the self would "divest" from its body identity and realign into the "bipolar being", which, then represents a unit microcosm mirroring the nondual macrocosm; thus an individual in being one with the absolute experiences bliss-considered as the power of the goddess (Shakti) in a tangible form. The Hindu tantric idea of the feminine and masculine principles arriving at unity in the "divine feminine" or the "unified divine consciousness" is analogous to the Analytical psychology idea of "coincidentia oppositorum", wherein the Anima/animus of an individual unite with the "spirit" to become one or whole.
In the Hindu tantric view, the women who participate in union rituals, thereby enabling men to attain self-realization are regarded as shakti or the goddess, as they are believed to embody her. Recognition of the deity in an objective woman is centered upon a man's acceptance of the subjective feminine and the primacy of her desires. Tricarico professed that modern-day pornography in its essence is a "desacralised, technological, and consumerist" equivalent of the ancient sacred prostitution a custom that involved honoring of the sacred feminine and worship of the prostitutes as goddess. The feminine is believed to embody particular qualities of the sacred or divine more broadly and deeply than the masculine, consequently in women, the ability to incorporate nondualistic awareness is assumed to be higher. Tricarico argued that women in porn, through their performances of many sexual acts, would inadvertently approach the non-differentiated state, an effect which he called the "intimation of hierophany". "Porn actresses may embody the medium to enter what used to be the realm of the sacred", he said. The actresses have been likened to the "descendants of the lost goddesses" who are now offering the gift of the "numinous" to all through their performances, but are unacknowledged or devalued for their contributions.
The use of epithets like "bitch", "whore", "slut" for sexually active women has been attributed to the denial of the subjective feminine by men. The subdued acceptance of female sexuality, as a value in its own right, is manifested when a man's admiration for the "bitch" gets subtended if she happens to be his wife or girlfriend. Along with showing "admiration, lust, gratitude, and desire", men show brazen hate and disgust towards women, this behavioral dichotomy had been ascribed to the "patriarchal hypocrisy" embedded in men. The unconscious perception by men of the greater ability in women to reach the undifferentiated state of psyche is reasoned to be a cause for their intentional humiliation, wilful devaluation, and deliberate belittlement of women.
According to Julia Kristeva, a psychoanalyst scholar, the psychological rejection and fear of the mother figure in males is the root cause for their behaviors that seek to subjugate women. Men in their infancy live in a state of "undifferentiated physical and psychic fusion" with the mother, experiencing "emotional exhilaration and jouissance". However, as they mature, sensing their separateness from the mother, they seek to become independent subjects and take recourse to paternal images and patriarchal behaviors with the hope of eliminating any possible further "undifferentiated/psychotic fusion" with the mother as they feel threatened by it. According to psychoanalyst Melanie Klein, the rejection and fear of the maternal image, in females, leads them to reject their own femininity. Tricarico hoped that porn becomes a place where men discard patriarchal antics, women embrace the sacred aspects, and audience incorporate porn as a joyful experience for the body – a genuine form of play that helps them approach the non-differentiated state. In being with other, we differentiate ourselves, and experience jouissance whilst becoming a unit being.
Religious attitudes
Many religions have long and vehemently opposed a wide range of sexual behaviors, as a result religious people are found highly susceptible to experience great distress in their use of pornography. Religious people who use pornography tend to feel sexually ashamed. Sexual shame—which arises from a person's perception of their self in other peoples mind, and a negative assessment of their own sexuality—is considered a powerful factor that over time governs an individual's behavior. As sexuality is interwoven into one's personal identity, sexual shame or sexual embarrassment are found to attack the person's very sense of self.
When a sexual shaming event occurs, the person attributes causation to oneself, resulting in self condemnation, and experience feelings of sadness, loneliness, anger, unworthiness, and rejection, along with a perceived judgment of their self by others. In this mental landscape, a fear arises that ones sexual self needs to be hiden. This psychological process initiates and fuels further shame and lowers one's self-esteem. Sexual shame constricts the "psychic space for free play with one's sexuality". Sexual shame in people begets more shame, and leads to a cycle of powerlessness culminating in deepening negative emotions. Those who tend to feel shame easily are found to be at greater risk for depression and anxiety disorders. According to clinical psychologist Gershen Kaufman, all Sexual disorders are majorly "disorders of shame".
The cause of attributing shame to sexuality is traced back to the biblical interpretation of nakedness being shameful. Much of the Christian mythology presented sexuality as an obstacle to be surmounted in the way of salvation. The major abrahamic religions condemn and consider all forms of nonmarital and nonreproductive sexual pleasure as unacceptable. In Hinduism, bhoga (sexual pleasure) is celebrated as a value in itself and is considered one of the two ways to nirvana, the other being the more demanding yoga. A central concept in Hinduism, purushartha, advocates pursuit of the four main goals for happiness: dharma (virtue), artha (riches), kama (pleasure), and moksha (freedom). The pursuit of Kama was elaborated by the sage Vatsyayana in his treatise Kama Sutra, which states that sexual pleasure and food are essential for the well-being of the body, and on both of them depend virtue and prosperity. Food, despite causing indigestion sometimes, would still be consumed regularly, and so it must be with pleasure, which must be pursued with caution while eliminating unwanted or harmful effects. As no one abstains from cooking food worrying about beggars who ask for it, or restrain from sowing wheat fearing animals that destroy the crop, similarly, instructs Vatsyayana, that men and women acquire knowledge of Kama by the time they reach youth and pursue it even though dangers exist; and those who become accomplished in Dharma, Artha, and Kama would attain highest happiness in this world and hereafter.
According to the Buddha, happiness is of two types: one derived from "domestic life" and the other from "monastic life", and between the two, monastic kind is "superior". As a result of the Buddha's effective advocacy for monasticism, in Buddhist communities, marriage and divorce remained civil matters and never acquired sacremental significance. Counsel over sex life for householders was minimal, while for the monks it was extensive as in Vinaya since all sexual behaviors were meant to be suppressed for the sake of enlightenment. The early Buddhist texts castigated women as detrimental beings. The Buddha himself said often that a woman's body is "a vessel of impurity, full of stinking filth. It is like a rotten pit ... like a toilet, with nine holes pouring all sorts of filth." Once when it came to his notice that a monk, Suddina, transgressed celibacy with his wife for the sake of progeny, the Buddha chided him saying, "It were better for you, foolish man, that your male organ should enter the mouth of a terrible and poisonous snake, than that it should enter a woman." Per the Buddha, all sexual desires are incompatible with enlightenment. In Buddhism, people who even derive pleasure from watching others engage in sexual activity were relegated as pandaka (pusillanimous). The Buddha said sexuality is a fetter that must be evaded completely and men who engage with it are "impure" and will not be freed from "old age". After the Buddha died in old age, subsequent generations of Buddhists resolved their problematic attitudes towards sex by accommodating different views.
According to Indonesia's foremost Islamic preacher, Abdullah Gymnastiar, shame is a noble emotion commanded in the Quran and was held high by Muhammad, who had been quoted as saying "Faith is compiled of seventy branches... and shame is one of them." To cultivate shame in Muslims, their sexual gaze needs to be checked, as unchecked gaze is believed to be the door through which Satan enters and soils the heart. In 2006, when anti-pornography protests erupted in Indonesia, the world's most populous Muslim-majority country, over the publication of the inaugural Indonesian edition of PlayboyAbdullah called for a legislation to ban pornography and embarked on a mission to shroud the state with a sense of shame, giving the slogan "the more shameful, the more faithful". During these protests, Indonesia's foremost Islamic newspaper, Republika, published daily front-page editorials which featured a logo of the word pornografi crossed out with a red X. The Jakarta office of Playboy Indonesia was ransacked by the members of Islamic Defenders Front (Front Pembela Islam or FPI), and bookstore owners were threatened not to sell any issue of the magazine. Consequently, in December 2008, Indonesian lawmakers signed an anti-pornography bill into law with overwhelming political support.
Highly religious people are more likely to support policies against pornography such as censorship than less religious people. Ironically, regions with highly religious and conservative people were found to search for more pornography on the Internet. Religious people are prone to having obsessive thoughts regarding sin and punishment by God over their pornography use causing them to feel ashamed, and perceive themselves to have pornography addiction while also suffering from OCD related symptoms. A study of sexually active religious people found that those who are highly spiritually matured have less shame, while those who are not spiritually matured have high shame.
Critical aspects
As per evaluation by medical professionals, pornography can neither be good nor bad as it does not endorse or advocate a single set of values regarding sex. As such, individuals may introspect their own values with regards to sex while evaluating pornography. The relationship between pornography and its audience is found to be complex. While many users reported their use to have had positive effects, others especially women were found to be troubled with body image issues, the cause of which is attributed to the unrealistic image of "beauty" that pornography portrays. The increasing prevalence of alleged beauty enhancing procedures such as breast augmentation and labiaplasty among the common populace has been attributed to the popularity of pornography.
Data from pornographic websites regarding the viewing habits of people is studied by academics to analyze the sexual preferences and mating choices. More often men look for women who have larger chest and hips, with a smaller Waist–hip ratio. Women are found to prefer men who are taller, stronger, appear highly masculine, and are in roles that can provide resources while being protective (CEO, doctor, athlete, lawmen).
Studies on harmful effects of pornography include finding any potential influence of pornography on rape, domestic violence, sexual dysfunction, difficulties with sexual relationships, and child sexual abuse. A longitudinal study had ascertained that pornography use cannot be a perpetrating factor in intimate partner violence.
A 2020 study that analyzed depictions in video-pornography found that normative sexual behaviors (e.g., vaginal intercourse, fellatio) were the most commonly depicted, while depictions of extreme acts of violence and rape were very rare. There is no clear evidence to assume that pornography is a cause of rape. Several studies conclude that liberalization of porn in society may be associated with decreased rates of rape and sexual violence, while others have suggested no effect, or are inconclusive. No correlation has been found between pornography use and the practice of sexual consent or lack thereof.
Mental health experts are divided over the issue of pornography use being a problem for people. While some literature reviews suggest pornography use can be addictive, insufficient evidence exists to draw conclusions. According to clinical psychologist and certified sex therapist David Ley, calling pornography an "addiction" has been "an area of substantial, protracted controversy and debate". Ley explained pornography doesn't effect an adult brain or body in the way alcohol or drugs do, he said "An alcoholic going cold turkey can have seizures and die because their brain has become physiologically dependent on the alcohol, but no one has ever had seizures or died from not getting to watch porn when they want to." Scholars have stated that pornography use has no implication on public health as it does not meet the definition of a public health crisis. Neuroscience has noted that minds of the young are in developmental stages and exposure to emotionally charged material such as pornography would likely have an impact on them unlike on adults, and has suggested caution while enabling potential access to such material.
Opposition to pornography use has been associated to many issues with sexual satisfaction, gender violence, and marital quality (wives watching pornography more frequently scored much better than the rest). Some issues of doxing and revenge porn had been linked to a few pornography websites. Since the mid-2010s deepfake pornography has become an issue of concern.
See also
Adult animation
Cartoon pornography
Erotic comics
Erotic hypnosis
Pornotopia
Pornocracy
Right to sexuality
Sex in advertising
Sex worker
Sexual and reproductive health and rights
Notes
References
Citations
Works cited
Books
Pdf.
Journals and magazines
News and websites
External links
Sexuality | Pornography | [
"Biology"
] | 19,577 | [
"Behavior",
"Sexuality",
"Sex"
] |
5,710,698 | https://en.wikipedia.org/wiki/Olefin%20fiber | Olefin fiber is a synthetic fiber made from a polyolefin, such as polypropylene or polyethylene. It is used in wallpaper, carpeting, ropes, and vehicle interiors.
Olefin's advantages are its strength, colorfastness and comfort, its resistance to staining, mildew, abrasion, and sunlight, and its good bulk and cover.
History
Italy began production of olefin fibers in 1957. The chemist Giulio Natta successfully formulated olefin suitable for more textile applications. Both Natta and Karl Ziegler were later awarded the Nobel Prize for their work on transition metal catalysis of olefins to fiber, also known as Ziegler–Natta catalysis. Production of olefin fibers in the U.S. began in 1960. Olefin fibers account for 16% of all manufactured fibers.
Major fiber properties
Olefin fibers have great bulk and cover while having low specific gravity. This means “Warmth without the weight.” The fibers have low moisture absorption, but they can wick moisture and dry quickly. Olefin is abrasion, stain, sunlight, fire, and chemical resistant. It does not dye well, but has the advantage of being colorfast. Since Olefin has a low melting point, textiles can be thermally bonded. The fibers have the lowest static of all manufactured fibers and a medium luster. One of the most important properties of olefin is its strength. It keeps its strength in wet or dry conditions and is very resilient. The fiber can be produced for strength of different properties.
Production method
The Federal Trade Commission's official definition of olefin fiber is “A manufactured fiber in which the fiber forming substance is any long-chain synthetic polymer composed of at least 85% by weight of ethylene, propylene, or other olefin units”
Polymerization of propylene and ethylene gases, controlled with special catalysts, creates olefin fibers. Dye is added directly to the polymer before melt spinning is applied. Additives, polymer variations and different process conditions can create a range of characteristics.
High pressure production, which uses ten tons per square inch, creates a film for molded materials. Low pressure production uses a low temperature with a catalyst and hydrocarbon solvent. This process is less expensive and produces a polyethylene polymer more for textile use.
The polymer is then melted, spun, by a spinneret into water, or air cooled. The fiber is drawn out to six times the spun length. Gel spinning is a new method in which a gel form of polyethylene polymers is used.
Physical and chemical structure
Physical
Olefin fibers can be multi- or monofilament and staple, tow, or film yarns. The fibers are colorless and round in cross section. This cross section can be modified for different end uses. The physical characteristics are a waxy feel and colorless.
Chemical
There are two types of polymers that can be used in olefin fibers. The first, polyethylene, is a simple linear structure with repeating units. These fibers are used mainly for ropes, twines and utility fabrics.
The second type, polypropylene, is a three-dimensional structure with a backbone of carbon atoms. Methyl groups protrude from this backbone. Stereoselective polymerization orders these methyl groups to the same spatial placement. This creates a crystalline polypropylene polymer. The fibers made with these polymers can be used in apparel, furnishing and industrial products.
Manufacturers
The first commercial producer of an olefin fiber in the United States was Hercules, Inc. (FiberVisions). Other U.S. olefin fiber producers include Asota; American Fibers and Yarns Co; American Synthetic Fiber, LLC; Color-Fi; FiberVisions; Foss Manufacturing Co., LLC; Drake Extrusion; Filament Fiber Technology, Inc.; TenCate Geosynthetics; Universal Fiber Systems LLC.
Trademarks according to fabric use
Producer – Allied-Signal
A.C.E. – Tire cord, furniture webbing
Producer – DuPont
CoolMax – Warm-weather and action wear
Hollofil, Quallofil – Fiberfill and insulating fibers
Sontara – Spunlaced nonwoven fabrics
Thermostat – Cold-weather wear
Thermoloft – Fiberfill and insulating fibers
Tyvek – Used for house wraps to postal envelopes to clothing
Producer – Trevira
ESP – Apparel and furnishings
Celwet – Nonwovens
Comfort Fiber – Staple fiber for apparel uses
Floor Guardian – Gym Floor Carpet Protection System
Loftguard – Staple fiber for industrial uses
Polar Guard
Lambda – Filament yarns with spun-yarn characteristics
Serene
Superba
Trevira HT – Marine and military uses; ropes, cordages
Trevira ProEarth – Recycled-content geotextiles
Trevira XPS – Carpeting
BTU – Cold-weather apparel
Producer – 3M
Thinsulate – Cold-weather action wear
Uses
Apparel
Sports & active wear, socks, hoodies, thermal underwear; lining fabrics.
Home furnishing
Olefin can be used by itself or in blends for indoor and outdoor carpets, carpet tiles, and carpet backing. The fiber can also be used in upholstery, draperies, wall coverings, slipcovers, and floor coverings. It is often used in basements due to its quick-drying and mold-resistant properties.
Automotive
Olefin can be used for interior fabrics, sun visors, arm rests, door and side panels, trunks, parcel shelves, and resin replacement as binder fibers.
Industrial
In an industrial setting, olefin creates carpets; ropes, geo-textiles that are in contact with the soil, filter fabrics, bagging, concrete reinforcement, and heat-sealable paper (e.g. tea- and coffee-bags).
Care procedures
When dry-cleaned, many dry-cleaning solvents can swell Olefin fibers. Since Olefin dries quickly, line drying and low tumble drying with little or no heat is recommended. Since Olefin is not absorbent, waterborne stains do not present a problem. However, oily stains are difficult to remove, though lukewarm water, detergent, and bleach can be used to remove such stains. Olefin fiber has a low melting point (around 225 to 335 °F (107 to 168 °C), depending on the polymer's grade) so care must be taken to iron these at a low temperature, as to prevent melting. Items such as outdoor carpets and other fabrics can be hosed off. Olefin is easy to recycle.
See also
Alkene
Elastolefin
References
Synthetic fibers
1957 introductions | Olefin fiber | [
"Chemistry"
] | 1,379 | [
"Synthetic materials",
"Synthetic fibers"
] |
5,710,861 | https://en.wikipedia.org/wiki/Cartan%E2%80%93Kuranishi%20prolongation%20theorem | Given an exterior differential system defined on a manifold M, the Cartan–Kuranishi prolongation theorem says that after a finite number of prolongations the system is either in involution (admits at least one 'large' integral manifold), or is impossible.
History
The theorem is named after Élie Cartan and Masatake Kuranishi. Cartan made several attempts in 1946 to prove the result, but it was in 1957 that Kuranishi provided a proof of Cartan's conjecture.
Applications
This theorem is used in infinite-dimensional Lie theory.
See also
Cartan-Kähler theorem
References
M. Kuranishi, On É. Cartan's prolongation theorem of exterior differential systems, Amer. J. Math., vol. 79, 1957, p. 1–47
Partial differential equations
Theorems in analysis | Cartan–Kuranishi prolongation theorem | [
"Mathematics"
] | 177 | [
"Mathematical analysis",
"Theorems in mathematical analysis",
"Mathematical theorems",
"Mathematical problems"
] |
5,711,642 | https://en.wikipedia.org/wiki/Senseless%20violence | Senseless violence () is a term frequently used by among others the media, politicians and NGOs to define the nature of several shocking events in Belgium and the Netherlands in recent years. The use of the term is politically charged and may not reflect any unique elements of any particular crime given that label.
The term expresses the perceived senselessness of the occurred acts of violence; the perpetrator and the victim do not know each other, the violence seems not to be motivated by greed or other common factors. The violence occurs suddenly and often under the influence of alcohol.
Origin of the term
The term "senseless violence", in the meaning used in this article, was first used in 1997 by Cees Bangma, district chief of the Dutch police unit Midden-Friesland. Before 1997 the term did not carry the same moral connotation in Belgian and Dutch culture, and typically referred to overseas warzone violence. Bangma used it in a letter written to the Leeuwarder Courant, a Frisian newspaper in which he made an appeal to the Dutch population to have a minute of silence for Meindert Tjoelker, who was killed on 13 September 1997. This minute was necessary "to make it clear to everyone that the Frisian society does not accept senseless violence". A wave of reactions followed, which also included media hype. As a consequence, much more attention was spent to every similar case of violence, which led to the perception that violence was on the increase.
A political group Landelijke Stichting Tegen Zinloos Geweld (national foundation against senseless violence) was created and people created the ladybug tile as a memorial or reminder against senseless violence. The group sent guest teachers to schools and sport associations, but became rather inactive since ca. 2009.
Criticism
The term is often criticized. Some people think that violence is never legitimate and consider the term to be a tautology. Others say that the term has never been clearly defined and does not help to understand a particular phenomenon. Others point out that the term is or can be misused by politicians who strive for more repressive measures against crimes.
In 2016, the national newspaper NRC reported about a recent case of youngsters mistreating a homeless person. The newspaper quoted a spokesperson of the police who said that hardly any violence happens out of the blue. Criminologists have started to use the term uitgaansgeweld instead, violence occurring going out in the evening to pubs and bars. Because of the local approach there are no recent national figures about the phenomenon, according to an expert.
Belgium
Documented deadly incidents include Guido Demoor, a train-driver who died after being struck on the head on an Antwerp bus by six youths he had asked to calm down, on June 24, 2006, and the death of an MIVB employee after being struck by a man in April 2012, leading to a multi-day strike by the Brussels transport services.
Netherlands
August 21, 1983: Kerwin Duinmeijer (stabbed to death in a racism related case)
October 22, 2002: René Steegmans (beaten to death after asking respect for an elderly lady)
December 2, 2012: Richard Nieuwenhuizen (fatally injured after serving as a volunteer linesman at a youth football match in Almere)
See also
Crime in Belgium
Happy slapping
References
Violence in Belgium
Violence in the Netherlands
Violence | Senseless violence | [
"Biology"
] | 700 | [
"Behavior",
"Aggression",
"Human behavior",
"Violence"
] |
5,711,799 | https://en.wikipedia.org/wiki/Trump%20Plaza%20Hotel%20and%20Casino | Trump Plaza was a hotel and casino on the Boardwalk in Atlantic City, New Jersey, owned by Trump Entertainment Resorts. Designed by architect Alan Lapidus, it operated from May 14, 1984, until September 16, 2014.
History
Early years
The Trump Organization, a company owned by real estate developer Donald Trump, began construction of the casino in June 1982. Harrah's, the gaming unit of Holiday Inn, joined as a partner a month later. Trump would oversee the construction, while Harrah's would operate the property, referred to as Harrah's Boardwalk, after opening.
The property opened as Harrah's at Trump Plaza on May 14, 1984. The complex contained 614 rooms, seven restaurants, a health club, a 750-seat showroom and a casino, all on a narrow plot of land next to Caesars Atlantic City. Five months after opening, the name was changed to simply Trump Plaza, to avoid confusion with Harrah's Marina. Part of the reason for this is that Harrah's was commonly associated with and attracted low-rolling gamblers, but Trump had built 85 high-roller suites, which were rarely used. The casino performed poorly, with pre-tax profits of just $144,000 in the first half of 1985. The poor results exacerbated disagreements between Trump and Harrah's, leading to Trump buying out Harrah's interest in the property for $70 million in May 1986.
In 1989, Trump paid $62 million to purchase the neighboring, unfinished Penthouse Boardwalk Hotel and Casino, including a hotel tower that had formerly been a Holiday Inn, and a nearby parking lot. Trump expanded the Plaza onto the Penthouse site, renaming it Trump Plaza Hotel and Casino East Tower. Trump also spent $63 million to purchase the bankrupt Atlantis Casino Hotel, separated from Trump Plaza by the Atlantic City Convention Hall, and rebranded it as the Trump Regency, a hotel annex to the Plaza.
Trump Plaza hosted the WrestleMania IV and WrestleMania V events in 1988 and 1989 respectively. Although the World Wrestling Federation billed the events as being held at Trump Plaza, in reality Trump was only the sponsor of both events, which were held at the Atlantic City Boardwalk Hall. From 1985 to 1998, the hotel was also the onsite host of 19 professional boxing program events.
The casino was the scene of a notorious baccarat session in May 1990, in which the Japanese high roller Akio Kashiwagi lost $10 million. The incident was later fictionalized in Martin Scorsese's film Casino.
Decline
Trump Plaza's revenues took a sharp decline in 1990, due to competition from its newly opened sister property, the Trump Taj Mahal, which was a mile away. The casino narrowly averted default on a 1991 payment to bondholders by taking out a $25 million mortgage on its parking garage. Trump then negotiated a debt restructuring with the Plaza's creditors, under which their $250 million of debt would be exchanged for $200 million of bonds with a lower interest rate, plus $100 million of preferred stock. The plan was submitted as a prepackaged bankruptcy in March 1992.
In 1993, Atlantic City casino development authority began condemning hundreds of properties, for the expansion of Trump Plaza Hotel and Casino. In 1998, a court stopped the condemnation of the Sabatini's restaurant, one of the properties. In 2005, Donald Trump agreed to buy the property for around $2 million, exceeding the first offer of $700,000.
Construction of a $42-million expansion began in 1993. The plan called for demolition of the unfinished Penthouse casino, the addition of 30,000 square feet of gaming space, and renovation of the former Holiday Inn building to become Trump Plaza's East Tower, with 361 hotel rooms. The expansion was at the center of a major eminent domain court case, when Trump sought to obtain the property of Vera Coking, a retired homeowner whose house was adjacent to the Penthouse casino. Coking, represented by the Institute for Justice, was victorious, and plans to build a limousine parking lot were thwarted.
In 1995, Trump granted ownership of Trump Plaza to his new publicly traded company, Trump Hotels & Casino Resorts (later Trump Entertainment Resorts). The company also acquired the Trump Regency hotel.
The East Tower opened in two phases, in October 1995 and February 1996. The expansion continued with the May 1996 opening of Trump World's Fair, a $48-million renovation of the Trump Regency with an added casino, connected to Trump Plaza by a loggia across the Atlantic City Convention Hall.
In 2004, the building hosted UFC 50.
On May 24, 2011, Trump Entertainment Resorts announced that a decision would be made within two months to either sell the casino or to renovate and expand it, possibly with a joint venture partner. In February 2013, the company proposed to sell the property for $20 million to the Meruelo Group, a California-based company whose businesses include the Grand Sierra Resort in Reno. Meruelo planned to make significant investments in the property and rename it. The deal fell through when Carl Icahn, senior lender for Trump Plaza's mortgage, declined to approve the sale for the proposed price.
Closure
On July 12, 2014, it was reported that the Trump Plaza Hotel and Casino would close on September 16, 2014, if a buyer was not found, putting an estimated 1,000 employees out of work. In early August 2014, Donald Trump filed a lawsuit requesting his name be removed from the facility, because it had fallen into disrepair, in violation of the licensing agreement for his name.
Trump Plaza closed permanently on September 16, 2014. This was the fourth Atlantic City casino to close in 2014, after the Atlantic Club, Showboat, and Revel. The closure left approximately 1,300 employees out of work.
Demolition
The building was set to be demolished in the spring of 2018, except for the East Tower and the parking garage. However, on May 29, 2018, the demolition plans had been delayed until at least the following fall due to funding disputes. On December 14, 2018, another demolition deadline passed. Carl Icahn bought the deed to the land Trump Plaza sits on, and terminated the complicated lease on the land that drove potential buyers out in late December 2018.
On June 11, 2020, Mayor Marty Small Sr. announced that Icahn has submitted plans for the hotel towers to be imploded, as they were considered a danger to public safety because of falling debris. Most of Trump Plaza in Atlantic City was slated to be demolished on January 29, 2021. Atlantic City planned to auction off the right to press the button detonating the explosives, with the proceeds to benefit the Boys & Girls Club of Atlantic City. The auction was cancelled after lawyers for IEP AC Plaza LLC, a subsidiary company of Icahn Enterprises which owns the building, said they were unaware of the fundraiser and demanded it be stopped. The Trump Plaza Hotel and Casino was imploded on February 17, 2021. It became the second hotel-casino in Atlantic City to be demolished by an implosion after the Sands Hotel and Casino in 2007.
Hotel
Trump Plaza had 906 hotel rooms, and offered five room styles for guests to choose from. There were also several amenities provided to hotel guests, such as a pool and a fitness center.
Rooms and suites
Deluxe room: A regular hotel room. Accustomed by two queen-size beds, or one king-size bed.
Ocean View suite: The same luxuries as the Deluxe hotel room but with a view of the Atlantic Ocean.
Executive suite: A suite with two bedrooms and a living area as well as the kitchen.
Contemporary suite: A suite with three bedrooms and a living area as well as the kitchen.
Penthouse suite: A five bedroom suite with a marble/gold chandelier. Two living rooms, a kitchen, pool-area on the deck, and a statue of Donald John Trump in the foyer.
Amenities
Indoor pool
Spa
Salon
Fitness center
Casino
Trump Plaza contained 91,181 sq ft (8,471.0 m2) of gaming space and featured standard casino games such as slot machines, video poker, blackjack, poker, craps, roulette, baccarat, and others.
Dining
Trump Plaza had several restaurants.
Fine dining
Max's Steakhouse
Roberto's Ristorante
Casual dining
24 Central Cafe
China Cafe
Evo
Liquid Bar
Rainforest Cafe
Sarah's Cookies
Buffet (Various Names)
Room Service
Quick service
Häagen-Dazs
Nathan's Famous
Sbarro
Starbucks Coffee
Auntie Anne's
Bars and nightclubs
Trump Plaza contained one nightclub, Liquid Bar and Jezebel's, as well as a seasonal bar on the beach named The Beach Bar at Trump Plaza.
Shopping
There were a few shopping options for those wishing to shop at Trump Plaza.
Stores
Landau Jewelers
Front Page Gift Shop
Floral services
Events
SportsBoxing and mixed martial arts matches were commonly held at the casino. Most notably being the well-televised match between professional boxers Mike Tyson and José Ribalta on August 17, 1986.
See also
Gambling in New Jersey
List of tallest buildings in Atlantic City
References
External links
Defunct casinos in Atlantic City, New Jersey
Casino hotels
Donald Trump real estate
Boxing venues in Atlantic City, New Jersey
Mixed martial arts venues in New Jersey
Resorts in New Jersey
Skyscraper hotels in Atlantic City, New Jersey
1984 establishments in New Jersey
Hotels disestablished in 2014
2014 disestablishments in New Jersey
Hotels established in 1984
Hotel buildings completed in 1984
American companies disestablished in 2014
Buildings and structures demolished in 2021
Buildings and structures demolished by controlled implosion
Companies that filed for Chapter 11 bankruptcy in 1992
Companies that filed for Chapter 11 bankruptcy in 2014
Former skyscraper hotels
Demolished hotels in New Jersey
Businesses of Donald Trump that went bankrupt | Trump Plaza Hotel and Casino | [
"Engineering"
] | 1,996 | [
"Buildings and structures demolished by controlled implosion",
"Architecture"
] |
5,711,924 | https://en.wikipedia.org/wiki/Oxaloacetate%20decarboxylase | Oxaloacetate decarboxylase is a carboxy-lyase involved in the conversion of oxaloacetate into pyruvate.
It is categorized under .
Oxaloacetate decarboxylase activity in a given organism may be due to activity of malic enzyme, pyruvate kinase, malate dehydrogenase, pyruvate carboxylase and PEP carboxykinase or the activity of "real" oxaloacetate decarboxylases. The latter enzymes catalyze the irreversible decarboxylation of oxaloacetate and can be classified into (i) the divalent cation-dependent oxaloacetate decarboxylases and (ii) the membrane-bound sodium-dependent and biotin-containing oxaloacetate decarboxylases from enterobacteria.
Kinetic Properties
An oxaloacetate decarboxylase from the family of divalent cation dependent decarboxylases was isolated from Corynebacterium glutamicum in 1995 by Jetten et al. This enzyme selectively catalyzed the decarboxylation of oxaloacetate to pyruvate and CO2 with a Km of 2.1mM, Vmax of 158 umol, and kcat of 311 s^-1. Mn2+ was required for enzymatic activity with a Km of 1.2mM for Mn2+.
A oxaloacetate decarboxylase found in mitochondria and soluble cytoplasm was isolated and purified from rat liver cells in 1974 by Wojtcak et al. The enzyme was not activated by divalent cations nor inhibited by chelating agents. The determined Km value was 0.55mM and the pH optimum for the enzyme between 6.5 and 7.5.
Cytoplasmic Enzymes
Found in different microorganisms such as Pseudomonas, Acetobacter, C. glutamicum, Veillonella parvula, and A. vinelandii, cytoplasmic oxaloacetate decarboxylases are dependent on the presence of divalent cations such as , , , , or . These enzymes are inhibited by acetyl-CoA and ADP.
Membrane-Bound Enzymes
Membrane bound oxaloacetate decarboxylase was the first enzyme of the Na+ transport decarboxylase family demonstrated to act as primary Na+ pump. This enzyme family includes methylmalonyl-CoA decarboxylase, malonate decarboxylase, and glutanoyl-CoA decarboxylase, all of which are found exclusively in anaerobic bacteria.
Decarboxylating the beta-keto acid of oxaloacetate affords the necessary free energy to pump sodium ions across the lipid bilayer. The resulting sodium gradient drives the synthesis of ATP, solute transport, and motility. The overall reaction catalyzed by the pump is the exchange of two intracellular Na+ ions for one extra cellular H+ ion; the reaction is initiated by the enzyme-catalyzed decarboxylation of oxaloacetate in the carboxyltransferase domain of the alpha subunit, yielding pyruvate and carboxybiotin. The oxaloacetate decaboxylase pump is also reversible: at high concentrations of extracellular Na+, the pump will couple downhill movement of Na+ into the cytosol with the carboxylation of pyruvate to form oxaloacetate.
Members of this family of enzymes are typically trimers, composed of alpha, beta and gamma subunits. The beta and gamma subunits are integral membrane proteins. The ~45kDa beta subunit has nine transmembrane segments which serve to couple the decarboxylation of the carboxybiotin to the translocation of Na+ from the cytoplasm to the periplasm. The small ~9kDa gamma subunit is an integral membrane protein with a single helix at the N-terminus, followed by a hydrophilic C-terminal domain which interacts with the alpha subunit. The gamma subunit is essential for the overall stability of the complex, and likely serves as an anchor to hold the alpha and beta subunits in place. Furthermore, the gamma subunit significantly accelerates the rate of oxaloacetate decarboxylation in the alpha subunit, and this correlates with the coordination of a Zn2+ metal ion by several residues at the hydrophilic C-terminus.
The alpha subunit, which is ~65kDa, is a biotinylated peripheral membrane protein on the cytosolic side of the membrane. Within the alpha subunit is the carboxyl transferase (CT) domain, oxaloacetate decarboxylase gamma association domain, and biotin carboxyl carrier domain. The crystal structure of the CT domain forms a TIM barrel fold in a dimer formation that coordinates with a Zn2+ ion in a catalytic site. The enzyme is completely inactivated by specific mutagenesis of Asp17, His207, and His209, which serve as ligands for the Zn2+ metal ion, or by Lys178 near the active site, suggesting that Zn2+ as well as Lys178 are essential for catalysis.
See also
Pyruvate carboxylase
References
Further reading
External links
Protein families
EC 4.1.1 | Oxaloacetate decarboxylase | [
"Biology"
] | 1,154 | [
"Protein families",
"Protein classification"
] |
5,711,954 | https://en.wikipedia.org/wiki/Antique%20radio | An antique radio is a radio receiving set that is collectible because of its age and rarity.
Types of antique radio
Morse receivers
The first radio receivers used a coherer and sounding board, and were only able to receive continuous wave (CW) transmissions, encoded with Morse code (wireless telegraphy). Later transmission and reception of speech became possible, although Morse code transmission continued in use until the 1990s.
All the following sections concern speech-capable radio, or wireless telephony.
Early home-made sets
The idea of radio as entertainment took off in 1920, with the opening of the first stations established specifically for broadcast to the public such as KDKA in Pittsburgh and WWJ in Detroit. More stations opened in cities across North America in the following years and radio ownership steadily gained in popularity. Radio sets from before 1920 are rarities, and are probably military artifacts. Sets made prior to approximately 1924 were usually made on wooden breadboards, in small cupboard style cabinets, or sometimes on an open sheet metal chassis. Homemade sets remained a strong sector of radio production until the early 1930s. Until then there were more homemade sets in use than commercial sets.
Early sets used any of the following technologies:
Crystal set
Crystal set with carbon or mechanical amplifier
Basic Tuned Radio Frequency (TRF) Sets
Reaction Sets
Super-Regenerative Receiver
Superheterodyne Receiver
Crystal sets
These basic radios used no battery, had no amplification and could operate only high-impedance headphones. They would receive only very strong signals from a local station. They were popular among the less wealthy due to their low build cost and zero run cost. Crystal sets had minimal ability to separate stations, and where more than one high power station was present, inability to receive one without the other was a common problem.
Some crystal set users added a carbon amplifier or a mechanical turntable amplifier to give enough output to operate a speaker. Some even used a flame amplifier.
Tuned radio frequency sets
Tuned radio frequency sets (TRF sets) were the most popular class of early radio, primarily because the Radio Corporation of America (RCA) had a monopoly on the superheterodyne circuit patents and it was more profitable for companies to jump into radio manufacturing TRF sets. These used several valves (tubes) to provide RF amplification, detection, and audio amplification. Early TRF sets only operated headphones, but by the mid-1920s it was more common to use additional amplification to power a loudspeaker, despite the expense. The sound quality produced from "moving-iron" speakers used on such sets is sometimes described as torturous, although by the late 1920s the Kellogg-Rice dynamic (moving-coil) speaker had begun to find favor due to its superior sound-reproduction ability.
Speakers widely used on TRF sets included:
Moving iron speaker (horn or cone)
tin can, magnet & wire based speakers
moving coil speaker
TRF sets used no regeneration, and were merely several stages (typically three) of tuned RF amplifiers in series feeding a detector tube which extracted the audio intelligence from the RF signal. TRF sets, depending on the number of stages they employed, could have poor-to-superb sensitivity (ability of the set to pick up faint signals) and corresponding selectivity (ability to parse adjacent stations from one another). Audio reproduction quality of TRF sets was limited by the available loudspeakers. "High Fidelity" was not to become a radio marketing concept until the mid-1930s and was not realized until the advent of FM broadcasting.
Reaction sets, also known as regenerative receivers, rely on positive feedback to achieve adequate gain. This approach provided high performance with a minimum number of expensive vacuum tubes, but these receivers tended to radiate RF interference in their immediate vicinity. Consequently, there was a significant amount of hostility by neighbors of "regen" set users over maladjusted radios transmitting squealing noises and blocking on nearby properties.
Early TRF sets had typically two or three tuning knobs and tube filament voltage-control rheostats, all of which had to be set correctly to receive a station. Later (late 1920s) TRF sets had ganged tuning (one knob was used to control all stage tuning capacitors simultaneously), AC house current operation, and eliminated the filament voltage adjustments. All of these changes greatly simplified operation and made radio a household appliance that even a small child could operate, instead of the highly skilled hobbyists of the brief preceding generation. Reaction sets also had the filament adjustment rheostats for each valve, and again settings had to be right to achieve reception.
Superheterodyne receivers
In the era of early radio, only RCA and a select number of competing "prestige" radio manufacturers could afford to build a superheterodyne receiver (superhet). RCA had exclusive rights to the superheterodyne circuit patents and extracted high licensing fees from other companies who sought to build superhet sets. RCA also vigorously prosecuted patent infringers. This situation helped propel RCA to the forefront of radio manufacturers in the 1920s due to the higher efficiency of the superhet circuit- a situation which lasted until the patents expired in the early 1930s, at which time a flood of low-cost superheterodyne receivers hit the market.
Early (RCA-patent-era) superhets were often used with the relatively expensive moving coil speakers, which offer a quality of sound unavailable from moving iron speakers.
Most post-1932 commercial radios were superhets, and this technology is still in widespread use in radio receivers today, implemented with transistors or integrated circuits.
The advantages of superhets are:
Excellent sensitivity and selectivity
Ease of designing the set for multiple-band operation, enabling reception of foreign broadcasts ("Shortwave")
High stability
Well controlled bandwidth
Well shaped RF passband avoids the uncontrolled tone variations of TRF sets, and gives good selectivity
The disadvantages before about 1932 were:
High patent-licensing costs.
Need for specialized test equipment to perform conversion-stage filter alignments.
In general the technical and manufacturing advantages of the superhet ensured that the TRF set became quickly obsolete once the patent restrictions on superhets were eliminated.
Farm radios
Prior to the Rural Electrification Act of 1936, the vast majority of rural farms in America did not have electricity. Many rural areas of the Midwest and South did not receive commercial power until the 1960s. Until that point, special radios were made to run on DC power. The earliest so-called "farm radios" used the "A", "B", and "C" batteries typical of 1920s radio sets; these farm radios were identical to those used in cities. Somewhat later, farm radios were made to be run on from a car or tractor battery, using an electromechanical vibrator to create a pulsating DC current that could be stepped up through a transformer to create the high voltage needed for the plates of the tubes- exactly as contemporary car radios did. Other farm radios were designed to run on , from a bank of lead-acid storage batteries charged from a gas powered generator or a wind-charger. The 32-volt system could also power other specially made appliances as well as electric lights around the farm. Other farm radios, especially from the late 1930s to the 1950s, reverted to using a large "A-B" dry cell that provided both for the tube plates and for the tube filaments, as did most tube-based portable radios of that era.
Foxhole radios
World War 2 created widespread urgent need for radio communication, and foxhole sets were built by people without access to traditional radio parts. A foxhole radio is a simple crystal sets
radio receiver cobbled together from whatever parts one could make (which were very few indeed) or scrounged from junked equipment. Such a set typically used salvaged domestic wiring for an antenna, a double-edged safety-razor blade and pencil lead (or bent safety-pin) for a detector, and a tin can, magnet and some wire for an earpiece. Razor blades of the era were chemically coated ("blued") and this coating could function as a diode, in the same way that a galena cat's whisker detector operates.
Wooden consoles
The console radio was the center piece of household entertainment in the era of radio. They were big and expensive, costing hundreds of dollars in the late 1930s and were often coupled with a phonograph. Tending to be a major acquisition for a middle-class family, these large radios were usually placed in living rooms. Most early console radios were tall and narrow, but as the years went on they got shorter and wider in accordance with the Art Deco design precepts which had become popular
Consumer console radios were made by RCA, Philco, General Electric, Montgomery Ward (under the Airline brand name), Sears (under the Silvertone brand name), Westinghouse, Motorola, Zenith and others. Brands such as Zenith made a few high priced models ("Stratosphere") mainly produced moderately priced radios
Some premium makers such as E. H. Scott and Silver-Marshall started around $500–$800 range in the 1930s and 1940s.
Table-top wood-cased radios
Table top radios came in many forms:
"Cathedral style", an upright rectangular box with a rounded top
"Tombstone style" are rectangular boxes that are tall and narrow like a tombstone
"Table top" are rectangular, with width being the larger dimension. Table top radios are usually placed in the kitchen, living room, or bedroom, and sometimes used out on the porch.
Bakelite
The availability of the first mass-produced plastic Bakelite allowed designers much more creativity in cabinet styling, and significantly reduced costs. However, Bakelite is a very brittle plastic, and dropping a radio could easily crack or break the case. Bakelite is a brown-black mouldable thermosetting plastic, and is still used in some products today.
In the 1930s some radios were manufactured using Catalin, which is the phenolic resin component of bakelite, with no organic filler added, but nearly all historic bakelite radios are the standard black-brown bakelite color. Bakelite as used for radio cabinets was traditionally brown, and this color came from the ground walnut shell flour added to the thermosetting phenolic resin as an extender and strengthening agent.
Plastic era
The affordability of more modern light coloured thermoplastics in the 1950s made brighter designs practical. Some of these thermoplastics are slightly translucent.
Early transistor radios
The invention of the transistor made it possible to produce very small portable radios that did not need a warm-up time, and ran on much smaller batteries. They were convenient, though the prices were initially high and the sound quality of early models was not nearly as good as tube radios. Later models equalled or surpassed tube models in audio quality. Transistors also made it possible to manufacture portable FM radios, which was impractical using tubes.
Transistor radios were available in many sizes from console to table-top to matchbox. Transistors are still used in today's radios, though the integrated circuit containing a large number of transistors has surpassed the use of singly packed transistors for the majority of radio circuitry.
Transistor radios appeared on the market in 1954, but at a high price. By the 1960s, reduced prices and an increase in desire for portability made them very popular.
There was something of a marketing war over the number of transistors sets contained, with many models named after this number. Some sets even had non-functional reject transistors soldered to the circuit board, doing absolutely nothing, so the sales pitch could advertise a higher number of transistors.
Vacuum tube radios and early transistor radios were hand assembled. Today radios are designed with the assistance of computers and manufactured with much greater use of machinery.
Today's radios are usually uneconomical to repair because mass production and technological improvements in numerous areas have made them so inexpensive to buy, while the cost of human labor and workshop overheads have increased greatly in comparison.
Car radios
The earliest car radios appeared not long after commercial radio broadcasts commenced, but were experimental only. They were expensive, required a large aerial, reception was inconsistent, and they required adjustment in use, which was not very practical.
By the early 1930s most car radios, no longer experimental, were superheterodynes and used a vibrator power supply to step up the low voltage to high voltage ("B+" voltage of anywhere from ) for the vacuum tubes. Vibrators are relatively unreliable as electromechanical components of limited life, buzz audibly, and produce radio interference. A few radios used a bulkier and more expensive motor-generator or motor-alternator set called a "dynamotor" that spun a high-voltage generator or alternator using a 6- or 12-volt DC motor. Filaments were powered using 6- and later 12-volt DC power from the vehicle's electrical system directly.
With the introduction of transistors, the earlier ones suitable for audio frequencies only, car radios were valve sets with a transistor output stage; makers promoted them as transistor sets. Some historic car radios badged as transistorised are in reality of this type. All-transistor sets eventually replaced sets with vacuum tube after transistor technology improved and prices fell significantly.
Chrysler and Philco announced an all-transistor car radio in the April 28, 1955, edition of the Wall Street Journal. This Philco car radio model was the first tubeless auto set in history to be developed and produced. It was a $150 option for 1956 Chrysler and Imperial cars and hit the showroom floor on October 21, 1955.
Warm-up time
Most valve sets needed a few seconds for the valves to heat up, though there were exceptions. Warm-up times changed as valves went through several generations of design.
Bright emitter valves universal in the early 1920s came on in a small fraction of a second, effectively instantly.
Direct dull emitters typical of the late '20s and 1930s came on in around a second. This type of valve continued to be popular in battery sets for several decades more.
Indirect emitters used in more or less all mains valve radios from the late 1930s onward were slow to reach emission temperature, with wait times routinely exceeding 10 seconds.
The last generation of valves was nuvistors. These tiny devices reached emission temperature fairly quickly.
Use of vintage radios
Line-operated commercial sets
Using vintage radios generally requires inspection and repair or refurbishment before they can be safely operated. In most cases, at least the power supply section of line-operated radios must be refurbished to prevent damage to other components, but it can be assumed that most of the vintage capacitors are electrically "leaky" and that the electrolytic capacitors in the power supply have either lost capacity (leading to excess "hum") or shorted (potentially causing a damaging or fire-inducing short-circuit). In their original state, they complied only with the limited safety standards of the time, and almost none used fuses.
AC-operated radios using power transformers require repair and refurbishment of the power supply section before operation, as any failures are likely to stress or damage the power transformer, necessitating a costly repair.
AC/DC sets using a no power transformer may be either "curtain burners" using a resistance cord to drop the line voltage, or warm/hot chassis radios using a series-string filament circuit where the voltages add up to the line voltage. They were named "AC/DC" because they operated on either AC or DC line voltage, which was not possible with a transformer-based set.
"Curtain Burner" sets were common in the early 1930s "midget" sets. The name is an indication of the problem—the line cord contained resistors to drop the voltage and dissipated substantial power in the cord itself. When operating properly and the line cord was stretched to full length, the cord got "warm" and was safe enough (until the heat made the rubber insulation crack). When the cord was coiled up or otherwise insulated (like from a curtain resting on it) it could get very hot, and frequently caused a fire. Resistance line cords are no longer available and the vintage cords are no longer serviceable, so the radio must be partially redesigned with either a dropping capacitor, dropping resistor, or some other workaround for safe operation.
AC/DC sets lacking resistance line cords instead used tube filaments in series that added up to the line voltage, effectively moving the resistance into the radio. They use conventional line cords. These are the most common vintage radio in the US after about 1940 or so, as they were very inexpensive to manufacture. They are much less common in areas with 240 mains power, as there were few common tubes built to operate at the high voltages required. BC (medium wave/"AM") only radios like the "All American 5" design, and later AM/FM radios with more tubes, and even televisions were built using the same idea, because of the simplicity and low cost possible.
Either type of AC/DC radio can present the "hot" line of the line voltage on the chassis of the radio ("hot chassis") or isolated from the chassis by a single capacitor ("warm chassis"). This presents a safety problem, as depending on the direction of the non-polarized plug, the hot side of the line voltage can be connected directly to all the metal parts of the radio any time it is plugged in, regardless of whether it is powered on or not. Proper repair or refurbishment requires an isolation transformer to remove the live connection, and care should be taken to never touch any metal part of the radio (chassis mounting screws, bare control shafts, etc.) when the radio is plugged in. Many radios with a hot chassis use interlocks on the back to ensure that the line is disconnected before the rear can be accessed for tube replacement.
Later transistor-based AC table radios typically used power transformers and operate safely, but with likely hum from failed electrolytic capacitors in the power supply, and likely low volume from other failed electrolytic coupling capacitors. There were a few early transistor table radios using "hot chassis" principles, but these are very rare.
Early battery-operated sets
The minority of all-in-one commercial ac mains sets that appeared in the 1930s are plug & play. Such sets should be checked for the possible existence of live metalwork accessible to the user, and a general safety check is advisable. Many will need a repair of some sort.
However other not all-in-one types of pre-Depression-era radio are more demanding to put into service, being a long way from plug & play. Setting up such radios requires a bit of electronics skill.
There are several issues with them:
Failed components are to be expected, and these must be fault-found then repaired
Repair of parts is practical, but not trivial
Some of these sets never worked very well and may benefit from some skilled debugging
3 power supplies are needed to replace the originally used A, B and C batteries (unless self-biasing is used) (or DC mains).
A little detective work is needed to find out what PSU voltages are needed
A long wire antenna will need to be erected
Fitting a local ground (earth) is frequently necessary, and quite easy
A high impedance speaker (or transformer) is needed
Some means to keep fingers away from the exposed live connections on the rear is wise, and often legally obligatory.
With 1920s and earlier sets using bright emitter valves, the end user should understand the use of the filament rheostats to avoid rapid valve failure.
The user should realise that permitting historic reaction sets to oscillate causes them to transmit interference, which is illegal.
Negative supply DC mains sets should have their ground capacitor bypassed to convert them from live chassis to earthed chassis.
Sound quality
The sound quality of antique radios depends on the technologies used in the set. The type of speaker is the main differentiator, with mains or battery also making a significant difference.
All valve sets produce 2nd harmonic distortion, which is fairly euphonic. Some also produce significant 3rd harmonic distortion, which is less pleasant to the ear.
Discussion is often heard about the distortion of triode versus pentode valves, and single ended versus push pull, which affect the types of distortion produced, but these issues seem to be secondary in practice to the ones discussed in this article, and are already well covered in other articles.
Loudspeaker types
Moving iron speaker
Homemade pre-war sets usually used some form of moving iron speaker, usually horn or cone loaded, and occasionally disc loaded. The sound quality of such radios is generally unimportant, since almost any defect in the audio signal will be masked by the butchery visited upon it by the loudspeaker. The question of sound quality is heavily dominated by the speaker in these cases. Moving iron speakers suffer the following defects:
Gross non-linearity
Heavy intermodulation distortion
Little bass response
Poor treble response
Strong undamped resonance in the middle of the audio spectrum
Noisy chattering when presented with a loud bass note
Tendency of the moving iron to stick to the pole piece, resulting in a 'whack' sound followed by very little sound output.
Gross impedance mismatch
Need for adjustment
Prone to demagnetisation
Horn speakers were strongly directional
Cone speakers were readily damaged
The sound of moving iron speakers has a strong unmistakable character.
They were far from faithful in their reproduction of audio, and their technical specifications were poorly controlled. An example of this is their electrical impedance, which varied across the audio spectrum by a ratio of more than 100:1.
It is not unusual for an electronics student, on hearing some of the specs of these devices, to conclude that they could not have been capable of reproducing speech. Yet they do, and with a sound that can not be mistaken for anything else.
Inductor dynamic speaker
These enjoyed brief success but were quickly eclipsed by moving coil speakers. The Inductor Dynamic Speaker solved the worst problems of earlier moving iron types, and provided a relatively pleasant listening experience. The main defect of ID speakers was poor treble response, giving them a characteristic dull drone.
Moving coil speaker
These speakers were mostly of sufficient quality that the radio's characteristics become significant. Transformer coupled sets suffered loss of bass & reduced treble, grid leak sets where rf and af were amplified by the same valve gave some nonlinearity, and output stages always provided a little more non-linearity. However the quality of a moving coil equipped set can be pleasant, and mistakable for a modern portable radio.
See also
Vintage amateur radio
History of radio
References
External links
.
Timo's Radiopages - Antique Radio Collection in Finland
WhiteRadios.com - Antique Radio Gallery, History, and Appraisals - Website dedicated to collecting radios and perpetuating the love of the hobby.
Radio
History of radio
Radio electronics | Antique radio | [
"Engineering"
] | 4,799 | [
"Radio electronics"
] |
5,711,956 | https://en.wikipedia.org/wiki/Snake%20Nebula | The Snake Nebula (also known as Barnard 72) is a dark nebula in the Ophiuchus constellation. It is a small but readily apparent SP-shaped dust lane that snakes out in front of the Milky Way star clouds from the north-north-west edge of the bowl of the Pipe Nebula. Its thickness runs between 2′ and 3′ and runs around 6′ in the north-west / south-east orientation. A good view in a 4" to 6" telescope requires clear dark skies.
It is part of the much larger Dark Horse Nebula.
To the right of the Snake Nebula is Barnard 68. Below it are Barnard 69, Barnard 70, and Barnard 74.
External links
Dark nebulae
Barnard objects
Ophiuchus | Snake Nebula | [
"Astronomy"
] | 150 | [
"Ophiuchus",
"Constellations"
] |
4,280,408 | https://en.wikipedia.org/wiki/Sher%2025 | Sher 25 is a blue supergiant star in the constellation Carina, located approximately 25,000 light years from the Sun in the H II region NGC 3603 of the Milky Way. It is a spectral type B1Iab star with an apparent magnitude of 12.2. Its initial main sequence mass is calculated at 60 times the mass of the Sun, but a star of this type will have already lost a substantial fraction of that mass. It is unclear whether Sher 25 has been through a red supergiant phase or has just evolved from the main sequence, so the current mass is very uncertain.
The name derives from the original cataloguing of stars in NGC 3603 by David Sher. This catalogue entry is more fully referred to as NGC 3603 Sher 25 to distinguish it from stars potentially numbered 25 by Sher in other clusters (eg. NGC 3766). The same star was numbered 13 by Melnick, Tapia, and Terlevich (MTT 13) and 5 in a Hubble Space Telescope survey by Moffat, Drissen, and Shara (NGC 3603 MDS 5).
It is speculated that Sher 25 is near the point of exploding as a supernova, as it has recently thrown off matter in a pattern similar to that of supernova 1987A in the Large Magellanic Cloud, with a circumstellar ring and bipolar outflow filaments.
Regular variations in the doppler shift of the star's spectral lines with a period of a few days may be due to orbital motion about a companion star, or to pulsations of the star's surface.
References
External links
NGC 3603
Carina (constellation)
B-type supergiants
Luminous blue variables | Sher 25 | [
"Astronomy"
] | 357 | [
"Carina (constellation)",
"Constellations"
] |
4,280,837 | https://en.wikipedia.org/wiki/Video-signal%20generator | A video signal generator is a type of signal generator which outputs predetermined video and/or television oscillation waveforms, and other signals used in the synchronization of television devices and to stimulate faults in, or aid in parametric measurements of, television and video systems. There are several different types of video signal generators in widespread use. Regardless of the specific type, the output of a video generator will generally contain synchronization signals appropriate for television, including horizontal and vertical sync pulses (in analog) or sync words (in digital). Generators of composite video signals (such as NTSC and PAL) will also include a colorburst signal as part of the output.
Types of video signal generators
Video signal generators are primarily classed according to their function. In addition, they may be classified according to the video formats and interface standard they support—one generator may generate composite analog signals (typically NTSC, PAL, or both), another may generate CCIR 601, and a third may generate MPEG streams over an ASI.
Many manufacturers sell signal generation platforms, which can be populated with multiple modules providing the above capabilities (and supporting different formats). Many such platforms also include audio generation capability (as television includes audio as well as video), supporting either embedded audio or standalone audio formats.
Test signal generators
A test signal generator generates test patterns, and other useful test signals, for troubleshooting and analyzing television systems. These devices are generally intended for off-line use (test patterns are seldom broadcast, unless a station is not operating properly or is off the air at the time), as they output complete television signals.
Examples of signals output by such a device include:
Color bars, one of several test signals used to verify the proper reproduction of a TV system's color gamut, and/or that a television signal or plant is compliant with the appropriate analog transmission standards
Flat fields, a signal consisting of nothing but a specific color (typically white, black, a shade of gray, or one of the primary colors (red, green, and blue) at maximum saturation). A red field is especially important in PAL applications, as it is the "red difference" portion of the chroma signal whose phase alternates every line; the red field should appear as a solid block of color, with no visible "bands" going across the screen.
Multibursts, sweeps, and pulse signals, used to test the frequency response of a television system
Ramp signals and staircase signals, used to check the voltage linearity of a television system
Crosshatch patterns, used to check and calibrate alignment, aspect ratio, convergence, and both vertical and horizontal linearity
The bowtie signal, used to check the relative (inter-channel) timing of a component video signal.
Some generators achieved a relative popularity, due to channels broadcasting test cards for long periods where no programming was scheduled. Patterns associated with Philips (PM 5540, PM 5552, PM 5544, PM 5644), Grundig VG 1001 (FuBk) SMPTE (Color Bars), or Snell & Wilcox (Zone Plate) generators are generally well known.
A few specialized signals are used in digital environments:
The PLL test signal is a pathological test signal used to stress the phase-locked loop of a serial digital receiver; this is done by outputting a bit pattern which, after passing through the linear feedback shift register used to scramble serial digital signals, resulting (with a high degree of probability) in a long strings of zeroes or ones, followed by a long string of the opposite polarity, on the digital (NRZI) signal; an issue which can cause poorly designed PLLs to unlock.
The equalizer test signal is another pathological signal, consisting of a long string of zeroes or ones, followed by a single bit of the opposite polarity. It can cause poorly designed cable equalizers to malfunction.
The SDI Checkfield signal, standardized by SMPTE RP178 (for SD) and RP198 (for HD), is a test signal which contains one of the above signals in the upper portion of the video, and the other in the lower portion of the video.
In addition, sophisticated signal generators may allow modification of the video timing, adjustment of the gains of the various components (including out of range), the introduction of jitter or bit errors (into digital signals), the introduction of motion, or other effects.
VITS inserters
A vertical interval test signal inserter, or VITS inserter inserts test patterns into the vertical interval of a television signal. Unlike test signal generators; a VITS inserter is used to insert the test signal into live programming, so that inline measurements of a transmission chain can be made while the chain is operational. (As the vertical interval is typically not visible on end-user televisions, this can be done without producing any artifacts noticeable to viewers). Since VITS signals can often be transmitted, it is also possible for a television station to receive its own on-air feed, and use the VITS to detect and troubleshoot problems in on-air transmission.
Sync pulse generator
A sync pulse generator (SPG) is a special type of generator which produces synchronization signals, with a high level of stability and accuracy. These devices are used to provide a master timing source for a video facility. The output of an SPG will typically be in one of several forms, depending on the needs of the facility:
A continuous wave signal
In standard-definition applications, a bi-level sync signal, often with a colorburst signal in facilities that have analog equipment. Typically, this is either in NTSC or PAL format. As the resulting signal is usually indistinguishable from an all-black television signal of the same format, this sort of reference is commonly known as black or black burst.
In some high-definition applications, a 'tri-level sync' signal is used instead. This signal is virtually identical to the synchronization signal used in component analogue video (CAV); and is similar to the synchronization signals used in VGA (the main difference being, in VGA the horizontal and vertical syncs are carried on different wires; whereas TLS signals include both H and V syncs).
Logo inserters
Logo inserters are devices used to insert a television station's logo, or other fixed graphics, into a live television signal. Often called a "Bug Generator."
See also
Video display controller
Philips PM5540
Telefunken FuBK
ETP-1
Test card
References
External links
Tektronix, Inc.A Guide to Digital Television Systems and Measurements
Tektronix, Inc. NTSC Systems Television Measurements
Tektronix, Inc. PAL Systems Television Measurements
Video Products, Inc. Usage of Video Test Pattern Generator
Philips TV Measuring Equipment, 1980
Film and video technology
Electronic test equipment | Video-signal generator | [
"Technology",
"Engineering"
] | 1,426 | [
"Electronic test equipment",
"Measuring instruments"
] |
4,280,973 | https://en.wikipedia.org/wiki/Fundamental%20interpersonal%20relations%20orientation | Fundamental Interpersonal Relations Orientation (FIRO) is a theory of interpersonal relations, introduced by William Schutz in 1958. This theory mainly explains the interpersonal interactions of a local group of people. The theory is based on the belief that when people get together in a group, there are three main interpersonal needs they are looking to obtain – affection/openness, control and inclusion. Schutz developed a measuring instrument that contains six scales of nine-item questions, and this became version B (for "Behavior"). This technique was created to measure how group members feel when it comes to inclusion, control, and affection/openness or to be able to get feedback from people in a group.
Description
These categories measure how much interaction a person wants in the areas of socializing, leadership and responsibilities, and more intimate personal relations. FIRO-B was created, based on this theory, as a measurement instrument with scales that assess the behavioral aspects of the three dimensions. Scores are graded from 0–9 in scales of expressed and wanted behavior, which define how much a person expresses to others, and how much he wants from others. Schutz believed that FIRO scores in themselves were not terminal, and can and do change, and did not encourage typology; however, the four temperaments were eventually mapped to the scales of the scoring system, which led to the creation of a theory of five temperaments.
Schutz himself discussed the impact of extreme behavior in the areas of inclusion, control, and openness as indicated by scores on the FIRO-B (and the later Element-B). For each area of interpersonal need the following three types of behavior would be evident: (1) deficient, (2) excessive, and (3) ideal. Deficient was defined as indicating that an individual was not trying to directly satisfy the need. Excessive was defined as indicating that an individual was constantly trying to satisfy the need. Ideal referred to satisfaction of the need. From this, he identified the following types:
Schutz composed a "Matrix of Relevant Interpersonal Data", which he called "The Elephant". Each area consisted of a smaller matrix of "act" and "feel" by "Self to Other" (Action), "Other to Self" (Reaction), and "Self to Self".
"Act" and "Feel" divided the rows, which were:
"Desired Interpersonal Relations (Needs)", which denoted "satisfactory relations" in each area;
"Ideal Interpersonal Relations" is what would correspond to "moderate" expressed and wanted scores;
"Anxious Interpersonal Relations" was subdivided into rows of "Too much activity" (covering high expressed scores) and "Too little activity" (covering low expressed scores); both being divided into "Act" and "feel".
The last row was "Pathological Interpersonal relations", which was divided into "too much" and "too little", yielding:
"Psychotic (Schizophrenia)" as Too Little/Inclusion; (There was no "Too Much/Inclusion")
"Obsessive-compulsive" as Too Much/Control and "Psychopath" as Too Little/Control; and
"Neurotic" as too much and too little Affection.
"Self-to other (action)" corresponded to the expressed dimension, and "Other to self (Reaction)" was the basis for the wanted dimension (though it is phrased in terms of what people do, rather than what we want them to do, which would be similar to the later Element B).
We thus end up with the six dimensions as follows:
Expressed Inclusion (eI): "I initiate interaction with others" (High: "outstanding"; low "shy")
Wanted Inclusion (wI): "I want to be Included" (High: "friendly"; low: "aloof")
expressed Control (eC): "I try to control others" (High: "authoritarian"; low: "absent-minded")
Wanted Control (wC): "I want to be controlled" (High: "submissive"; low: "rebellious")
Expressed Affection (eA): "I try to be close and personal" (High: "empathetic"; low: "cold")
Wanted Affection (wA): "I want others to be close and personal with me" (High: "needy"; low: "defensive")
Putting them together, Schutz came up with fifteen "Descriptive Schema and appropriate terminology for each Interpersonal Need Area":
In 1977, a clinical psychologist who worked with FIRO-B, Dr. Leo Ryan, produced maps of the scores for each area, called "locator charts", and assigned names for all of the score ranges in his Clinical Interpretation of The FIRO-B:
However, to continue not to encourage typology, the names (which were for clinical interpretation primarily) are generally not used, and Element-B test results usually total the E, W, I, C and O scores individually. In the derivative "five temperament" system, the different scores are grouped into their corresponding temperaments, and considered inborn types. One key difference is in the "high wanted" scores in the area of Control. A distinction is made between men and women, with men being "dependent", and women, rather than really being dependent, only being "tolerant" of control by others. This is attributed to "the stereotypical role of women in Western Culture", where they were often dependent, and have simply learned to tolerate control from others. This again, reflects FIRO's belief that these scores reflect learned behavior. In five temperament theory, no such distinction between the sexes is recognized, and high wanted scores in Control are seen as an inborn dependency need in both sexes.
Compatibility Theory
Another part of the theory is "compatibility theory", which features the roles of originator, reciprocal, and interchange.
Originator compatibility, involves possible clashes between expressed and wanted behaviors. The example given, is two people with high eC and low wC (aka "Mission Impossible" or "Autocrat Rebellious"). They:
"will both want to originate the behaviors associated
with the Control needs, and neither will want to
receive those behaviors. Both persons will want to
set the agenda, take responsibility, and direct and
structure the actions of others; neither will feel
comfortable taking direction. The result could be
competition or even conflict."
Reciprocal compatibility is (from another example given from Control), where high eC with low wC interacts with the opposite: low eC with high wC ("Openly Dependent", "Loyal Lieutenant", or "Abdicrat Submissive").
"there is a high degree of reciprocal compatibility because...
one will take charge; the other will be happy to let him or her assume the responsibility."
Interchange compatibility measures how much individuals share the same need strengths.
The example is two people with both high eA and wA ("Optimist" or "Overpersonal Personal-compliant"). They
"will be compatible because both will see Affection behaviors as
the basis of the relationship, and they will engage
each other around Affection needs."
(i.e. freely give and receive).
Further development
During the 1970s, Schutz revised and expanded FIRO theory and developed additional instruments for measuring the new aspects of the theory, including Element B: Behavior (an improved version of FIRO-B); Element F: Feelings; Element S: Self; Element W: Work Relations; Element C: Close Relations; Element P: Parental Relationships; and Element O: Organizational Climate. Since 1984, these instruments have been known collectively as Elements of Awareness.
Element B differs in expanding the definitions of Inclusion, Control, and Affection (renamed "Openness"), into an additional six scores to measure how much a person wants to include, control, and be close to others, and how much other people include, control, and like to be close to the client. "Expressed" is renamed "See" (current behaviors) while "Want" remains desired behaviors. Each of the three areas is split into "Do" (initiating interaction with others) and "Get" (the level received from others). Differences between See and Want scores indicate levels of dissatisfaction.
The original FIRO-B was sold to CPP, Inc. (now The Myers-Briggs Company), which also publishes the MBTI assessment, and FIRO Element B is owned by Business Consultants Network, Inc.
A third FIRO system, called FIRO-Space™ is being developed by Dr. Henry L. Thompson who developed the second one.
Correlations with MBTI
In a 1976 survey of seventy-five of the most widely used training instruments, the FIRO-B was found to be the most generally usable instrument in training. The popularity of the FIRO-B began to wane as the MBTI became one of the instruments of choice in business. Since FIRO-B uses completely different scales from MBTI, and was not designed to measure inborn "types," it is often used together with the MBTI by workplaces. Now the two are offered together by The Myers-Briggs Company.
Statistical correlation has been observed between FIRO-B and MBTI by John W. Olmstead, and also Allen L. Hammer with Eugene R. Schnell; and between Element B and MBTI by Dr. Henry Dick Thompson.
Citations
References
1958 introductions
Human communication
Personality tests | Fundamental interpersonal relations orientation | [
"Biology"
] | 1,954 | [
"Human communication",
"Behavior",
"Human behavior"
] |
4,281,933 | https://en.wikipedia.org/wiki/ANZAC%20A%20badge | The ANZAC "A" badge is a brass insignia authorised in November 1917 for members of the First Australian Imperial Force who had served as a member of the Australian and New Zealand Army Corps (ANZACs) during the Gallipoli campaign in 1915. In 1918, eligibility was extended to those who had served at Lemnos, Imbros and Tenedos and the transports and hospitals off Gallipoli as well as the communications line to Egypt.
History
The origins of the award are uncertain with John Monash, William Birdwood and John Gellibrand all being credited with the idea in various accounts. The most likely version is that the award was a result of several ideas proposed in early 1916 to commemorate the Anzacs. When Monash led his brigade in commemorating the first Anzac Day, men who had served at Gallipoli wore a blue ribbon on their right breast and those who had gone ashore as part of the first landing wore a red ribbon as well. Birdwood advised in August 1916 that he supported Australian veterans of the ANZAC campaign wearing an "A" badge on their colour patches.
The 1st and 2nd Divisions supported the idea enthusiastically. The 3rd and 4th, both of which had fewer ANZAC veterans in their ranks, were less enthusiastic in their adoption of the badge. However, Monash, as commander of the 3rd Division, was able to claim by November 1916 that "'All who have a right to be called "Anzacs" among us are now wearing a metal "A" on the colour patches on the sleeves".
In early 1917, convalescent soldiers returned to Australia wearing the badge and its status was initially questioned. This led to its formal approval through AIF Order 937 issued in November 1917. Subsequent orders clarified the entitlement to the badge and made it compulsory. In January 1918, the order extended eligibility to people who had served behind the lines on the Greek islands of Lemnos, Imbros and Tenedos, on the communication lines and hospital ships offshore or on the islands or in the communications to Egypt. This included nurses who served in the hospital ships meaning that women as well as men received acknowledgement as ANZACS.
There was initial resentment of the badges by soldiers who had fought in France at the Battle of Pozières and the Battle of Mouquet Farm in 1916 who thought that their contribution had been equal to the Anzacs.
ANZAC rosettes were also worn by men who had joined in 1914 and came home on ANZAC leave to show that they had not been shirking their duty.
References
Australian Encyclopedia (1996), Volume 1, page 1.
External links
Anzacs.org "A is for Anzac"
Anzac Day org
Australian War Memorial ANZAC badge article
Australian military insignia
Australian campaign medals
Badges
ANZAC (Australia)
Military awards and decorations of World War I
Australia in World War I | ANZAC A badge | [
"Mathematics"
] | 572 | [
"Symbols",
"Badges"
] |
4,282,051 | https://en.wikipedia.org/wiki/Chow%20group | In algebraic geometry, the Chow groups (named after Wei-Liang Chow by ) of an algebraic variety over any field are algebro-geometric analogs of the homology of a topological space. The elements of the Chow group are formed out of subvarieties (so-called algebraic cycles) in a similar way to how simplicial or cellular homology groups are formed out of subcomplexes. When the variety is smooth, the Chow groups can be interpreted as cohomology groups (compare Poincaré duality) and have a multiplication called the intersection product. The Chow groups carry rich information about an algebraic variety, and they are correspondingly hard to compute in general.
Rational equivalence and Chow groups
For what follows, define a variety over a field to be an integral scheme of finite type over . For any scheme of finite type over , an algebraic cycle on means a finite linear combination of subvarieties of with integer coefficients. (Here and below, subvarieties are understood to be closed in , unless stated otherwise.) For a natural number , the group of -dimensional cycles (or -cycles, for short) on is the free abelian group on the set of -dimensional subvarieties of .
For a variety of dimension and any rational function on which is not identically zero, the divisor of is the -cycle
where the sum runs over all -dimensional subvarieties of and the integer denotes the order of vanishing of along . (Thus is negative if has a pole along .) The definition of the order of vanishing requires some care for singular.
For a scheme of finite type over , the group of -cycles rationally equivalent to zero is the subgroup of generated by the cycles for all -dimensional subvarieties of and all nonzero rational functions on . The Chow group of -dimensional cycles on is the quotient group of by the subgroup of cycles rationally equivalent to zero. Sometimes one writes for the class of a subvariety in the Chow group, and if two subvarieties and have , then and are said to be rationally equivalent.
For example, when is a variety of dimension , the Chow group is the divisor class group of . When is smooth over (or more generally, a locally Noetherian normal factorial scheme ), this is isomorphic to the Picard group of line bundles on .
Examples of Rational Equivalence
Rational Equivalence on Projective Space
Rationally equivalent cycles defined by hypersurfaces are easy to construct on projective space because they can all be constructed as the vanishing loci of the same vector bundle. For example, given two homogeneous polynomials of degree , so , we can construct a family of hypersurfaces defined as the vanishing locus of . Schematically, this can be constructed as
using the projection we can see the fiber over a point is the projective hypersurface defined by . This can be used to show that the cycle class of every hypersurface of degree is rationally equivalent to , since can be used to establish a rational equivalence. Notice that the locus of is and it has multiplicity , which is the coefficient of its cycle class.
Rational Equivalence of Cycles on a Curve
If we take two distinct line bundles of a smooth projective curve , then the vanishing loci of a generic section of both line bundles defines non-equivalent cycle classes in . This is because for smooth varieties, so the divisor classes of and define inequivalent classes.
The Chow ring
When the scheme is smooth over a field , the Chow groups form a ring, not just a graded abelian group. Namely, when is smooth over , define to be the Chow group of codimension- cycles on . (When is a variety of dimension , this just means that .) Then the groups form a commutative graded ring with the product:
The product arises from intersecting algebraic cycles. For example, if and are smooth subvarieties of of codimension and respectively, and if and intersect transversely, then the product in is the sum of the irreducible components of the intersection , which all have codimension .
More generally, in various cases, intersection theory constructs an explicit cycle that represents the product in the Chow ring. For example, if and are subvarieties of complementary dimension (meaning that their dimensions sum to the dimension of ) whose intersection has dimension zero, then is equal to the sum of the points of the intersection with coefficients called intersection numbers. For any subvarieties and of a smooth scheme over , with no assumption on the dimension of the intersection, William Fulton and Robert MacPherson's intersection theory constructs a canonical element of the Chow groups of whose image in the Chow groups of is the product .
Examples
Projective space
The Chow ring of projective space over any field is the ring
where is the class of a hyperplane (the zero locus of a single linear function). Furthermore, any subvariety of degree and codimension in projective space is rationally equivalent to . It follows that for any two subvarieties and of complementary dimension in and degrees , , respectively, their product in the Chow ring is simply
where is the class of a -rational point in . For example, if and intersect transversely, it follows that is a zero-cycle of degree . If the base field is algebraically closed, this means that there are exactly points of intersection; this is a version of Bézout's theorem, a classic result of enumerative geometry.
Projective bundle formula
Given a vector bundle of rank over a smooth proper scheme over a field, the Chow ring of the associated projective bundle can be computed using the Chow ring of and the Chern classes of . If we let and the Chern classes of , then there is an isomorphism of rings
Hirzebruch surfaces
For example, the Chow ring of a Hirzebruch surface can be readily computed using the projective bundle formula. Recall that it is constructed as over . Then, the only non-trivial Chern class of this vector bundle is . This implies that the Chow ring is isomorphic to
Remarks
For other algebraic varieties, Chow groups can have richer behavior. For example, let be an elliptic curve over a field . Then the Chow group of zero-cycles on fits into an exact sequence
Thus the Chow group of an elliptic curve is closely related to the group of -rational points of . When is a number field, is called the Mordell–Weil group of , and some of the deepest problems in number theory are attempts to understand this group. When is the complex numbers, the example of an elliptic curve shows that Chow groups can be uncountable abelian groups.
Functoriality
For a proper morphism of schemes over , there is a pushforward homomorphism for each integer . For example, for a proper scheme over , this gives a homomorphism , which takes a closed point in to its degree over . (A closed point in has the form for a finite extension field of , and its degree means the degree of the field over .)
For a flat morphism of schemes over with fibers of dimension (possibly empty), there is a homomorphism .
A key computational tool for Chow groups is the localization sequence, as follows. For a scheme over a field and a closed subscheme of , there is an exact sequence
where the first homomorphism is the pushforward associated to the proper morphism , and the second homomorphism is pullback with respect to the flat morphism . The localization sequence can be extended to the left using a generalization of Chow groups, (Borel–Moore) motivic homology groups, also known as higher Chow groups.
For any morphism of smooth schemes over , there is a pullback homomorphism , which is in fact a ring homomorphism .
Examples of flat pullbacks
Note that non-examples can be constructed using blowups; for example, if we take the blowup of the origin in then the fiber over the origin is isomorphic to .
Branched coverings of curves
Consider the branched covering of curves
Since the morphism ramifies whenever we get a factorization
where one of the . This implies that the points have multiplicities respectively. The flat pullback of the point is then
Flat family of varieties
Consider a flat family of varieties
and a subvariety . Then, using the cartesian square
we see that the image of is a subvariety of . Therefore, we have
Cycle maps
There are several homomorphisms (known as cycle maps) from Chow groups to more computable theories.
First, for a scheme X over the complex numbers, there is a homomorphism from Chow groups to Borel–Moore homology:
The factor of 2 appears because an i-dimensional subvariety of X has real dimension 2i. When X is smooth over the complex numbers, this cycle map can be rewritten using Poincaré duality as a homomorphism
In this case (X smooth over C), these homomorphisms form a ring homomorphism from the Chow ring to the cohomology ring. Intuitively, this is because the products in both the Chow ring and the cohomology ring describe the intersection of cycles.
For a smooth complex projective variety, the cycle map from the Chow ring to ordinary cohomology factors through a richer theory, Deligne cohomology. This incorporates the Abel–Jacobi map from cycles homologically equivalent to zero to the intermediate Jacobian. The exponential sequence shows that CH1(X) maps isomorphically to Deligne cohomology, but that fails for CHj(X) with j > 1.
For a scheme X over an arbitrary field k, there is an analogous cycle map from Chow groups to (Borel–Moore) etale homology. When X is smooth over k, this homomorphism can be identified with a ring homomorphism from the Chow ring to etale cohomology.
Relation to K-theory
An (algebraic) vector bundle E on a smooth scheme X over a field has Chern classes ci(E) in CHi(X), with the same formal properties as in topology. The Chern classes give a close connection between vector bundles and Chow groups. Namely, let K0(X) be the Grothendieck group of vector bundles on X. As part of the Grothendieck–Riemann–Roch theorem, Grothendieck showed that the Chern character gives an isomorphism
This isomorphism shows the importance of rational equivalence, compared to any other adequate equivalence relation on algebraic cycles.
Conjectures
Some of the deepest conjectures in algebraic geometry and number theory are attempts to understand Chow groups. For example:
The Mordell–Weil theorem implies that the divisor class group CHn-1(X) is finitely generated for any variety X of dimension n over a number field. It is an open problem whether all Chow groups are finitely generated for every variety over a number field. The Bloch–Kato conjecture on values of L-functions predicts that these groups are finitely generated. Moreover, the rank of the group of cycles modulo homological equivalence, and also of the group of cycles homologically equivalent to zero, should be equal to the order of vanishing of an L-function of the given variety at certain integer points. Finiteness of these ranks would also follow from the Bass conjecture in algebraic K-theory.
For a smooth complex projective variety X, the Hodge conjecture predicts the image (tensored with the rationals Q) of the cycle map from the Chow groups to singular cohomology. For a smooth projective variety over a finitely generated field (such as a finite field or number field), the Tate conjecture predicts the image (tensored with Ql) of the cycle map from Chow groups to l-adic cohomology.
For a smooth projective variety X over any field, the Bloch–Beilinson conjecture predicts a filtration on the Chow groups of X (tensored with the rationals) with strong properties. The conjecture would imply a tight connection between the singular or etale cohomology of X and the Chow groups of X.
For example, let X be a smooth complex projective surface. The Chow group of zero-cycles on X maps onto the integers by the degree homomorphism; let K be the kernel. If the geometric genus h0(X, Ω2) is not zero, Mumford showed that K is "infinite-dimensional" (not the image of any finite-dimensional family of zero-cycles on X). The Bloch–Beilinson conjecture would imply a satisfying converse, Bloch's conjecture on zero-cycles: for a smooth complex projective surface X with geometric genus zero, K should be finite-dimensional; more precisely, it should map isomorphically to the group of complex points of the Albanese variety of X.
Variants
Bivariant theory
Fulton and MacPherson extended the Chow ring to singular varieties by defining the "operational Chow ring" and more generally a bivariant theory associated to any morphism of schemes. A bivariant theory is a pair of covariant and contravariant functors that assign to a map a group and a ring respectively. It generalizes a cohomology theory, which is a contravariant functor that assigns to a space a ring, namely a cohomology ring. The name "bivariant" refers to the fact that the theory contains both covariant and contravariant functors.
This is in a sense the most elementary extension of the Chow ring to singular varieties; other theories such as motivic cohomology map to the operational Chow ring.
Other variants
Arithmetic Chow groups are an amalgamation of Chow groups of varieties over Q together with a component encoding Arakelov-theoretical information, that is, differential forms on the associated complex manifold.
The theory of Chow groups of schemes of finite type over a field extends easily to that of algebraic spaces. The key advantage of this extension is that it is easier to form quotients in the latter category and thus it is more natural to consider equivariant Chow groups of algebraic spaces. A much more formidable extension is that of Chow group of a stack, which has been constructed only in some special case and which is needed in particular to make sense of a virtual fundamental class.
History
Rational equivalence of divisors (known as linear equivalence) was studied in various forms during the 19th century, leading to the ideal class group in number theory and the Jacobian variety in the theory of algebraic curves. For higher-codimension cycles, rational equivalence was introduced by Francesco Severi in the 1930s. In 1956, Wei-Liang Chow gave an influential proof that the intersection product is well-defined on cycles modulo rational equivalence for a smooth quasi-projective variety, using Chow's moving lemma. Starting in the 1970s, Fulton and MacPherson gave the current standard foundation for Chow groups, working with singular varieties wherever possible. In their theory, the intersection product for smooth varieties is constructed by deformation to the normal cone.
See also
Intersection theory
Grothendieck–Riemann–Roch theorem
Hodge conjecture
Motive (algebraic geometry)
References
Citations
Introductory
Advanced
Algebraic geometry
Intersection theory
Topological methods of algebraic geometry
Zhou, Weiliang | Chow group | [
"Mathematics"
] | 3,157 | [
"Fields of abstract algebra",
"Algebraic geometry"
] |
4,282,370 | https://en.wikipedia.org/wiki/Leptomycin | Leptomycins are secondary metabolites produced by Streptomyces spp.
Leptomycin B (LMB) was originally discovered as a potent antifungal compound. Leptomycin B was found to cause cell elongation of the fission yeast Schizosaccharomyces pombe. Since then this elongation effect has been used for the bioassay of leptomycin. However, recent data shows that leptomycin causes G1 cell cycle arrest in mammalian cells and is a potent anti-tumor agent against murine experimental tumors in combination therapy.
Leptomycin B has been shown to be a potent and specific nuclear export inhibitor in humans and the fission yeast S. pombe. Leptomycin B alkylates and inhibits CRM1 (chromosomal region maintenance)/exportin 1 (), a protein required for nuclear export of proteins containing a nuclear export sequence (NES), by glycosylating a cysteine residue (cysteine 529 in S. pombe). In addition to antifungal and antibacterial activities, leptomycin B blocks the cell cycle and is a potent anti-tumor agent. At low nM concentrations, leptomycin B blocks the nuclear export of many proteins including HIV-1 Rev, MAPK/ERK, and NF-κB/IκB, and it inhibits the inactivation of p53. Leptomycin B also inhibits the export and translation of many RNAs, including COX-2 and c-Fos mRNAs, by inhibiting the export of ribonucleoproteins.
Leptomycin A (LPA) was discovered together with LMB. LMB is twice as potent as LPA.
See also
Selective inhibitor of nuclear export
References
External links
Original data copied with permission from Leptomycin B manufacturer product page (Fermentek)
Antibiotics | Leptomycin | [
"Biology"
] | 409 | [
"Antibiotics",
"Biocides",
"Biotechnology products"
] |
4,282,781 | https://en.wikipedia.org/wiki/Ayn%20Ghazal%20%28archaeological%20site%29 | Ayn Ghazal () is a Neolithic archaeological site located in metropolitan Amman, Jordan, about 2 km (1.24 mi) north-west of Amman Civil Airport. The site is remarkable for being the place where the ʿAin Ghazal statues were found, which are among the oldest large-sized statues ever discovered.
Background
The settlement at Ayn Ghazal ('Spring of the Gazelle') first appeared in the Middle Pre-Pottery Neolithic B (MPPNB) and is split into two phases. Phase I starts circa 10,300 Before Present (BP) and ends c. 9,950 BP, while phase II ends c. 9,550 BP.
The 9th millennium MPPNB period in the Levant represented a major transformation in prehistoric lifeways from small bands of mobile hunter–gatherers to large settled farming and herding villages in the Mediterranean zone, the process having been initiated some 2–3 millennia earlier.
In its prime era, circa 7000 BCE (9000 BP), the site extended over 10–15 hectares (25–37 ac) and was inhabited by ca. 3,000 people (four to five times the population of contemporary Jericho). After 6500 BC, however, the population dropped sharply to about one sixth within only a few generations, probably due to environmental degradation, the 8.2 kilo-year event (Köhler-Rollefson 1992).
Location and physical dimensions
It is situated in a relatively rich environmental setting immediately adjacent to the Zarqa River (Wadi Zarqa), the longest drainage system in highland Jordan. It is located at an elevation of about 720 m within the ecotone between the oak-park woodland to the west and the open steppe-desert to the east.
Ayn Ghazal started as a typical aceramic, Neolithic village of modest size. It was set on terraced ground in a valley-side, and was built with rectangular mud-brick houses that accommodated a square main room and a smaller anteroom. Walls were plastered with mud on the outside, and with lime plaster inside that was renewed every few years.
Evidence recovered from the excavations suggests that much of the surrounding countryside was forested and offered the inhabitants a wide variety of economic resources. Arable land is plentiful within the site's immediate environs. These variables are atypical of many major Neolithic sites in the Near East, several of which are located in marginal environments. Yet despite its apparent richness, the area of Ayn Ghazal is climatically and environmentally sensitive because of its proximity throughout the Holocene to the fluctuating steppe-forest border.
In Ayn Ghazal, the early Pottery Neolithic period starts c. 6,400 BC, and continues to 5,000 BC.
Economy
As an early farming community, the Ayn Ghazal people cultivated cereals (barley and ancient species of wheat), legumes (peas, beans, lentils and chickpeas) in fields above the village, and herded domesticated goats. In addition, they hunted wild animals – deer, gazelle, equids, pigs and smaller mammals such as fox or hare.
The estimated population of the MPPNB site from Ayn Ghazal is of 259–1349 individuals with an area of 3.01–4.7 ha. It is argued that at its founding at the commencement of the MPPNB Ayn Ghazal was likely about 2 ha in size and grew to 5 ha by the end of the MPPNB. At this point in time their estimated population was 600–750 people or 125–150 people per hectare.
The diet of the occupants of PPNB Ayn Ghazal was varied. Domesticated plants included wheat and barley species, but legumes (primarily lentils and peas) appear to have been preferred cultigens. Wild plants also were consumed. The determination of domesticated animals, sensu stricto, is a topic of much debate. At PPNB Ayn Ghazal goats were a major species, and they were used in a domestic sense, although they may not have been morphologically domestic. Many of the phalanges recovered exhibit pathologies that are suggestive of tethering. An impressive range of wild animal species also were consumed at the site. Over 50 taxa have been identified, including gazelle, Bos, Sus sp., Lepus, and Vulpes.
Ayn Ghazal was in an area that was suitable for agriculture. Archaeologists think that throughout the mid east much of the land was exhausted after some 700 years of planting and so became unsuitable for agriculture. The people from those small villages abandoned their unproductive fields and migrated, with their domestic animals, to places with better ecological conditions, like Ayn Ghazal that could support larger populations. As opposed to other sites as new people migrated to Ayn Ghazal, probably with few possessions and possibly starving, class distinctions began to develop. The influx of new people placed stresses on the social fabric – new diseases, more people to feed from what was planted and more animals that needed grazing.
There are evidences of mining activities as part of a production sequence conducted by craftsmen at the site of Ayn Ghazal, these potential part-time specialists in some way controlled access to such raw materials.
Genetics
Y-DNA haplogroups such as E1b1b1b2 (E-Z830) has been found in remains at Ayn Ghazal, along with the general PPNB populations and in most Natufians. Haplogroup T1a (T-M70) has also been found among the Pre-Pottery Neolithic B inhabitants from Ayn Ghazal, and is currently the oldest known sample ever found at any ancient site. This second haplotype marker wasn't found among the early Levant epipaleolithic populations.
It is thought therefore, based on uniparental and autosomal data, that the Pre-Pottery Neolithic B populations at Ayn Ghazal Jordan, were mostly composed of two to three different populations: the members of the early Natufian industries, a population resulting from immigration from Anatolia, and another likely from the Fertile Crescent in Iraq or possibly Iran originating near Ganj Dareh.
Culture
Statues
In the earlier levels at Ayn Ghazal there are small ceramic figures that seem to have been used as personal or familial ritual figures. There are figurines of both animals and people. The animal figures are of horned animals and the front part of the animal is the most clearly modeled. They all give the impression of dynamic force. Some of the animal figures have been stabbed in their vital parts; these figures have then been buried in the houses. Other figurines were burned and then discarded with the rest of the fire. They built ritual buildings and used large figurines or statues. The actual building of them is also a way for an elite group to demonstrate and underline its authority over those who owe the community or the elite labor as service and to bond laborers together as part of a new community. In addition to the monumental statues, small clay and stone tokens, some incised with geometric or naturalistic shapes, were found at Ayn Ghazal.The 195 figurines (40 human and 155 animal) recovered were from MPPNB contexts; 81% of the figurines have been found to belong to the MPPNB while only 19% belonging to the LPPNB and PPNC. The vast majority of figurines are of cattle, a species that makes up only 8% of the overall number of identified specimens (NISP) count. The importance of hunted cattle to the domestic ritual sphere of Ayn Ghazal is telling. It was seemingly of importance for individual households to have members who participated both the hunting of cattle – likely a group activity – and the subsequent feasting on the remains.
Ayn Ghazal is renowned for a set of anthropomorphic statues found buried in pits in the vicinity of some special buildings that may have had ritual functions. These statues are half-size human figures modeled in white plaster around a core of bundled twigs. The figures have painted clothes, hair, and in some cases, ornamental tattoos or body paint. The eyes are created using plaster with a bitumen pupil and dioptase highlighting.
In all, 32 of those plaster figures were found in two caches, 15 of them full figures, 15 busts, and 2 fragmentary heads. Three of the busts were two-headed.
Burial practices
Considerable evidence for mortuary practices during the PPNB period have been described in recent years. Post-mortem skull removal, commonly restricted to the cranium, but on occasion including the mandible, and apparently following preliminary primary interments of the complete corpse. Such treatment has commonly been interpreted as representing rituals connected with veneration of the dead or some form of "ancestor worship".
There is evidence of class in the way the dead were treated. Some people were buried in the floors of their houses. After the flesh had wasted away, often the head was later retrieved and the skull buried in a separate shallow pit beneath the house floor, and some of the skulls were decorated. This could have been either a form of respect or so that they could impart their power to the house and the people in it. However, some people were thrown on trash heaps and their bodies remain intact, indicating that not every deceased was ceremoniously put to rest.
Scholars have estimated that a third of adult burials were found in trash pits with their heads intact. Why only some of the inhabitants were properly buried and others simply disposed of remains unresolved. Burials seem to have taken place approximately every 15–20 years, indicating a rate of one burial per generation, though gender and age were not constant in this practice.
Excavation and conservation
The site is located at the boundary between Amman's Tariq and Basman districts, next to, and named for, the Ayn Ghazal Interchange connecting Al-Shahid Street and Army Street (Ayn Ghazal is the name of a minor village just north of the road, now within Tariq district).
The site was discovered in 1974 by developers who were building Army St, the road connecting Amman and Zarqa. Excavation began in 1982, however by this time, around 600 meters (1,970 ft) of road ran through the site. Despite the damage urban expansion brought, what remained of Ayn Ghazal provided a wealth of information and continued to do so until 1989. One of the more notable archaeological finds during these first excavations came to light in 1983. While examining a cross section of earth in a path carved out by a bulldozer, archaeologists came across the edge of a large pit 2.5 meters (8 ft) under the surface containing plaster statues.
Another set of excavations, under the direction of Gary O. Rollefson and Zeidan Kafafi took place in the early 1990s.
The site was included in the 2004 World Monuments Watch by the World Monuments Fund to call attention to the threat of encroaching urban development.
Relative chronology
References
Footnotes
Further reading
External links
ʿAin Ghazal statues at Smithsonian Institution
'Ain Ghazal Excavation Reports (menic.utexas.edu)
Institut du Monde Arabe ()
UCL (University College London): The ʿAin Ghazal Statue Project ()
The Joukowsky Institute of Archaeology
Photos of Ain Ghazal at the American Center of Research
Ain Ghazal – An Ancient Mystery
Populated places established in the 8th millennium BC
Populated places disestablished in the 5th millennium BC
Ain Ghazal
Former populated places in Jordan
Neolithic settlements
1974 archaeological discoveries
Collection of the Jordan Museum
Megasites
Pre-Pottery Neolithic B | Ayn Ghazal (archaeological site) | [
"Physics",
"Mathematics"
] | 2,427 | [
"Quantity",
"Megasites",
"Physical quantities",
"Size"
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4,282,921 | https://en.wikipedia.org/wiki/Monochloramine | Monochloramine, often called chloramine, is the chemical compound with the formula NH2Cl. Together with dichloramine (NHCl2) and nitrogen trichloride (NCl3), it is one of the three chloramines of ammonia. It is a colorless liquid at its melting point of , but it is usually handled as a dilute aqueous solution, in which form it is sometimes used as a disinfectant. Chloramine is too unstable to have its boiling point measured.
Water treatment
Chloramine is used as a disinfectant for water. It is less aggressive than chlorine and more stable against light than hypochlorites.
Drinking water disinfection
Chloramine is commonly used in low concentrations as a secondary disinfectant in municipal water distribution systems as an alternative to chlorination. This application is increasing. Chlorine (referred to in water treatment as free chlorine) is being displaced by chloramine—to be specific, monochloramine—which is much less reactive and does not dissipate as rapidly as free chlorine. Chloramine also has a much lower, but still active, tendency than free chlorine to convert organic materials into chlorocarbons such as chloroform and carbon tetrachloride. Such compounds have been identified as carcinogens and in 1979 the United States Environmental Protection Agency (EPA) began regulating their levels in US drinking water.
Some of the unregulated byproducts may possibly pose greater health risks than the regulated chemicals.
Due to its acidic nature, adding chloramine to the water supply may increase exposure to lead in drinking water, especially in areas with older housing; this exposure can result in increased lead levels in the bloodstream, which may pose a significant health risk. Fortunately, water treatment plants can add caustic chemicals at the plant which have the dual purpose of reducing the corrosivity of the water, and stabilizing the disinfectant.
Swimming pool disinfection
In swimming pools, chloramines are formed by the reaction of free chlorine with amine groups present in organic substances, mainly those biological in origin (e.g., urea in sweat and urine). Chloramines, compared to free chlorine, are both less effective as a sanitizer and, if not managed correctly, more irritating to the eyes of swimmers. Chloramines are responsible for the distinctive "chlorine" smell of swimming pools, which is often misattributed to elemental chlorine by the public. Some pool test kits designed for use by homeowners do not distinguish free chlorine and chloramines, which can be misleading and lead to non-optimal levels of chloramines in the pool water.
There is also evidence that exposure to chloramine can contribute to respiratory problems, including asthma, among swimmers. Respiratory problems related to chloramine exposure are common and prevalent among competitive swimmers.
Though chloramine's distinctive smell has been described by some as pleasant and even nostalgic, its formation in pool water as a result of bodily fluids being exposed to chlorine can be minimised by encouraging showering and other hygiene methods prior to entering the pool, as well as refraining from swimming while suffering from digestive illnesses and taking breaks to use the bathroom, instead of simply urinating in the pool.
Safety
US EPA drinking water quality standards limit chloramine concentration for public water systems to 4 parts per million (ppm) based on a running annual average of all samples in the distribution system. In order to meet EPA-regulated limits on halogenated disinfection by-products, many utilities are switching from chlorination to chloramination. While chloramination produces fewer regulated total halogenated disinfection by-products, it can produce greater concentrations of unregulated iodinated disinfection byproducts and N-nitrosodimethylamine. Both iodinated disinfection by-products and N-nitrosodimethylamine have been shown to be genotoxic, causing damage to the genetic information within a cell resulting in mutations which may lead to cancer.
Another newly-identified byproduct of chloramine is chloronitramide anions, whose toxicity has not yet been determined.
Lead poisoning incidents
In the year 2000, Washington, DC, switched from chlorine to monochloramine, causing lead to leach from unreplaced pipes. The number of babies with elevated blood lead levels rose about tenfold, and by one estimate fetal deaths rose between 32% and 63%.
Trenton, Missouri made the same switch, causing about one quarter of tested households to exceed EPA drinking water lead limits in the period from 2017 to 2019. 20 children tested positive for lead poisoning in 2016 alone. In 2023, Virginia Tech Professor Marc Edwards said lead spikes occur in several water utility system switchovers per year, due to lack of sufficient training and lack of removal of lead pipes. Lack of utility awareness that lead pipes are still in use is also part of the problem; the EPA has required all water utilities in the United States to prepare a complete lead pipe inventory by October 16, 2024.
Synthesis and chemical reactions
Chloramine is a highly unstable compound in concentrated form. Pure chloramine decomposes violently above . Gaseous chloramine at low pressures and low concentrations of chloramine in aqueous solution are thermally slightly more stable. Chloramine is readily soluble in water and ether, but less soluble in chloroform and carbon tetrachloride.
Production
In dilute aqueous solution, chloramine is prepared by the reaction of ammonia with sodium hypochlorite:
NH3 + NaOCl → NH2Cl + NaOH
This reaction is also the first step of the Olin Raschig process for hydrazine synthesis. The reaction has to be carried out in a slightly alkaline medium (pH 8.5–11). The acting chlorinating agent in this reaction is hypochlorous acid (HOCl), which has to be generated by protonation of hypochlorite, and then reacts in a nucleophilic substitution of the hydroxyl against the amino group. The reaction occurs quickest at around pH 8. At higher pH values the concentration of hypochlorous acid is lower, at lower pH values ammonia is protonated to form ammonium ions (), which do not react further.
The chloramine solution can be concentrated by vacuum distillation and by passing the vapor through potassium carbonate which absorbs the water. Chloramine can be extracted with ether.
Gaseous chloramine can be obtained from the reaction of gaseous ammonia with chlorine gas (diluted with nitrogen gas):
2 NH3 + Cl2 NH2Cl + NH4Cl
Pure chloramine can be prepared by passing fluoroamine through calcium chloride:
2 NH2F + CaCl2 → 2 NH2Cl + CaF2
Decomposition
The covalent N−Cl bonds of chloramines are readily hydrolyzed with release of hypochlorous acid:
RR′NCl + H2O RR′NH + HOCl
The quantitative hydrolysis constant (K value) is used to express the bactericidal power of chloramines, which depends on their generating hypochlorous acid in water. It is expressed by the equation below, and is generally in the range 10−4 to 10−10 ( for monochloramine):
In aqueous solution, chloramine slowly decomposes to dinitrogen and ammonium chloride in a neutral or mildly alkaline (pH ≤ 11) medium:
3 NH2Cl → N2 + NH4Cl + 2 HCl
However, only a few percent of a 0.1 M chloramine solution in water decomposes according to the formula in several weeks. At pH values above 11, the following reaction with hydroxide ions slowly occurs:
3 NH2Cl + 3 OH− → NH3 + N2 + 3 Cl− + 3 H2O
In an acidic medium at pH values of around 4, chloramine disproportionates to form dichloramine, which in turn disproportionates again at pH values below 3 to form nitrogen trichloride:
2 NH2Cl + H+ NHCl2 +
3 NHCl2 + H+ 2 NCl3 +
At low pH values, nitrogen trichloride dominates and at pH 3–5 dichloramine dominates. These equilibria are disturbed by the irreversible decomposition of both compounds:
NHCl2 + NCl3 + 2 H2O → N2 + 3 HCl + 2 HOCl
Reactions
In water, chloramine is pH-neutral. It is an oxidizing agent (acidic solution: , in basic solution ):
NH2Cl + 2 H+ + 2 e− → + Cl−
Reactions of chloramine include radical, nucleophilic, and electrophilic substitution of chlorine, electrophilic substitution of hydrogen, and oxidative additions.
Chloramine can, like hypochlorous acid, donate positively charged chlorine in reactions with nucleophiles (Nu−):
Nu− + NH3Cl+ → NuCl + NH3
Examples of chlorination reactions include transformations to dichloramine and nitrogen trichloride in acidic medium, as described in the decomposition section.
Chloramine may also aminate nucleophiles (electrophilic amination):
Nu− + NH2Cl → NuNH2 + Cl−
The amination of ammonia with chloramine to form hydrazine is an example of this mechanism seen in the Olin Raschig process:
NH2Cl + NH3 + NaOH → N2H4 + NaCl + H2O
Chloramine electrophilically aminates itself in neutral and alkaline media to start its decomposition:
2 NH2Cl → N2H3Cl + HCl
The chlorohydrazine (N2H3Cl) formed during self-decomposition is unstable and decomposes itself, which leads to the net decomposition reaction:
3 NH2Cl → N2 + NH4Cl + 2 HCl
Monochloramine oxidizes sulfhydryls and disulfides in the same manner as hypochlorous acid, but only possesses 0.4% of the biocidal effect of HClO.
See also
Disinfection
Disinfection by-products
Water treatment
Pathogen
Chloramines
References
External links
"Chlorinated drinking water", IARC Monograph (1991)
EPA Maximum Contaminant Levels
WebBook page for NH2Cl
Chlorine and chloramines in the freshwater aquarium
Drinking water
Inorganic amines
Inorganic chlorine compounds
Nitrogen halides
Water treatment | Monochloramine | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 2,298 | [
"Inorganic compounds",
"Water treatment",
"Water pollution",
"Inorganic chlorine compounds",
"Environmental engineering",
"Water technology"
] |
4,283,705 | https://en.wikipedia.org/wiki/W3C%20Software%20Notice%20and%20License | The W3C Software Notice and License is a permissive free software license used by software released by the World Wide Web Consortium, like Amaya. The license is a permissive license, compatible with the GNU General Public License.
Software using the License
Arena
Amaya
Libwww
Line Mode Browser
See also
Free software portal
Software using the W3C Software Notice and License (category)
World Wide Web Consortium
References
External links
Text of the license
Free and open-source software licenses | W3C Software Notice and License | [
"Engineering"
] | 99 | [
"Software engineering",
"Software engineering stubs"
] |
4,283,745 | https://en.wikipedia.org/wiki/Algebraic%20expression | In mathematics, an algebraic expression is an expression built up from constants (usually, algebraic numbers) variables, and the basic algebraic operations:
addition (+), subtraction (-), multiplication (×), division (÷), whole number powers, and roots (fractional powers).. For example, is an algebraic expression. Since taking the square root is the same as raising to the power , the following is also an algebraic expression:
An algebraic equation is an equation involving polynomials, for which algebraic expressions may be solutions.
If you restrict your set of constants to be numbers, any algebraic expression can be called an arithmetic expression. However, algebraic expressions can be used on more abstract objects such as in Abstract algebra. If you restrict your constants to integers, the set of numbers that can be described with an algebraic expression are called Algebraic numbers.
By contrast, transcendental numbers like and are not algebraic, since they are not derived from integer constants and algebraic operations. Usually, is constructed as a geometric relationship, and the definition of requires an infinite number of algebraic operations. More generally, expressions which are algebraically independent from their constants and/or variables are called transcendental.
Terminology
Algebra has its own terminology to describe parts of an expression:
1 – Exponent (power), 2 – coefficient, 3 – term, 4 – operator, 5 – constant, - variables
Conventions
Variables
By convention, letters at the beginning of the alphabet (e.g. ) are typically used to represent constants, and those toward the end of the alphabet (e.g. and ) are used to represent variables. They are usually written in italics.
Exponents
By convention, terms with the highest power (exponent), are written on the left, for example, is written to the left of . When a coefficient is one, it is usually omitted (e.g. is written ). Likewise when the exponent (power) is one, (e.g. is written ), and, when the exponent is zero, the result is always 1 (e.g. is written , since is always ).
In roots of polynomials
The roots of a polynomial expression of degree n, or equivalently the solutions of a polynomial equation, can always be written as algebraic expressions if n < 5 (see quadratic formula, cubic function, and quartic equation). Such a solution of an equation is called an algebraic solution. But the Abel–Ruffini theorem states that algebraic solutions do not exist for all such equations (just for some of them) if n 5.
Rational expressions
Given two polynomials and
, their quotient is called a rational expression or simply rational fraction. A rational expression is called proper if , and improper otherwise. For example, the fraction is proper, and the fractions and are improper. Any improper rational fraction can be expressed as the sum of a polynomial (possibly constant) and a proper rational fraction. In the first example of an improper fraction one has
where the second term is a proper rational fraction. The sum of two proper rational fractions is a proper rational fraction as well. The reverse process of expressing a proper rational fraction as the sum of two or more fractions is called resolving it into partial fractions. For example,
Here, the two terms on the right are called partial fractions.
Irrational fraction
An irrational fraction is one that contains the variable under a fractional exponent. An example of an irrational fraction is
The process of transforming an irrational fraction to a rational fraction is known as rationalization. Every irrational fraction in which the radicals are monomials may be rationalized by finding the least common multiple of the indices of the roots, and substituting the variable for another variable with the least common multiple as exponent. In the example given, the least common multiple is 6, hence we can substitute to obtain
Algebraic and other mathematical expressions
The table below summarizes how algebraic expressions compare with several other types of mathematical expressions by the type of elements they may contain, according to common but not universal conventions.
A rational algebraic expression (or rational expression) is an algebraic expression that can be written as a quotient of polynomials, such as . An irrational algebraic expression is one that is not rational, such as .
See also
Algebraic function
Analytical expression
Closed-form expression
Expression (mathematics)
Precalculus
Term (logic)
Notes
References
External links
Elementary algebra | Algebraic expression | [
"Mathematics"
] | 896 | [
"Elementary mathematics",
"Algebra",
"Elementary algebra"
] |
4,284,946 | https://en.wikipedia.org/wiki/Ultrarelativistic%20limit | In physics, a particle is called ultrarelativistic when its speed is very close to the speed of light . Notations commonly used are or or where is the Lorentz factor, and is the speed of light.
The energy of an ultrarelativistic particle is almost completely due to its kinetic energy . The total energy can also be approximated as where is the Lorentz invariant momentum.
This can result from holding the mass fixed and increasing the kinetic energy to very large values or by holding the energy fixed and shrinking the mass to very small values which also imply a very large . Particles with a very small mass do not need much energy to travel at a speed close to . The latter is used to derive orbits of massless particles such as the photon from those of massive particles (cf. Kepler problem in general relativity).
Ultrarelativistic approximations
Below are few ultrarelativistic approximations when . The rapidity is denoted :
Motion with constant proper acceleration: , where is the distance traveled, is proper acceleration (with ), is proper time, and travel starts at rest and without changing direction of acceleration (see proper acceleration for more details).
Fixed target collision with ultrarelativistic motion of the center of mass: where and are energies of the particle and the target respectively (so ), and is energy in the center of mass frame.
Accuracy of the approximation
For calculations of the energy of a particle, the relative error of the ultrarelativistic limit for a speed is about %, and for it is just %. For particles such as neutrinos, whose (Lorentz factor) are usually above ( practically indistinguishable from ), the approximation is essentially exact.
Other limits
The opposite case () is a so-called classical particle, where its speed is much smaller than . Its kinetic energy can be approximated by first term of the binomial series:
See also
Relativistic particle
Classical mechanics
Special relativity
Aichelburg–Sexl ultraboost
References
Special relativity
Approximations
pt:Limite ultra-relativístico | Ultrarelativistic limit | [
"Physics",
"Mathematics"
] | 428 | [
"Special relativity",
"Mathematical relations",
"Relativity stubs",
"Theory of relativity",
"Approximations"
] |
4,286,042 | https://en.wikipedia.org/wiki/List%20of%20FTP%20server%20return%20codes | FTP server return codes always have three digits, and each digit has a special meaning. The first digit denotes whether the response is good, bad or incomplete:
The second digit is a grouping digit and encodes the following information:
Below is a list of all known return codes that may be issued by an FTP server.
See also
List of FTP commands
List of HTTP status codes
References
RFC 1123 Requirements for Internet Hosts - Application and Support
RFC 1635 How to Use Anonymous FTP
RFC 2389 Feature negotiation mechanism for the File Transfer Protocol
RFC 2428 FTP Extensions for IPv6 and NATs
RFC 2616 Hypertext Transfer Protocol -- HTTP/1.1
RFC 2822 Internet Message Format
RFC 3659 Extensions to FTP
RFC 3986 Uniform Resource Identifier (URI)
Computer errors
File Transfer Protocol
Internet-related lists | List of FTP server return codes | [
"Technology"
] | 171 | [
"Computing-related lists",
"Computer errors",
"Internet-related lists"
] |
4,286,150 | https://en.wikipedia.org/wiki/Liver%20spot | Liver spots (also known as age spot, solar lentigo, "lentigo senilis", "old age spot", "senile freckle") are blemishes on the skin associated with aging and exposure to ultraviolet radiation from the sun. They range in color from light brown to red or black and are located in areas most often exposed to the sun, particularly the hands, face, shoulders, arms and forehead, and the scalp if bald.
The spots derive their name from the fact that they were once incorrectly believed to be caused by liver problems, but they are physiologically unrelated to the liver, save for a similar color. From the age of 40, the skin is less able to regenerate from sun exposure, and liver spots are very common in this age group, particularly in those who spend time in the sun.
In the overwhelming majority of cases, liver spots pose no threat and require no treatment, though they occasionally have been known to obscure the detection of skin cancer. However, despite being a benign condition, liver spots are sometimes considered unsightly and some people choose to have them removed. This can be done by electrosurgery, laser treatment, cryotherapy, or the use of depigmentation agents, such as hydroquinone, tretinoin, topical cysteamine, azelaic acid, or alpha hydroxy acids.
Causes
Differently from the melanotic nevi and the verrucous nevi on the skin, age spots change in color and in shape with time. Wang-Michelitsch and Michelitsch propose a hypothesis inspired by their misrepair-accumulation aging theory for the development of age spots. They propose that aged basal cells contain lipofuscin bodies that cannot be removed and might promote the aging of neighboring cells, generating a feedback loop that causes more and more neighbor cells to become aged and contain lipofuscins. Such cells might then aggregate into a spot with an irregular shape. They propose that the protrusion of a flat spot is a result of the death of aged cells in the spot and release of lipofuscin bodies. The aggregating cells would form a capsule, and the dense lipofuscin bodies make the protruding spot soft and dark in color. However, this proposal appeared as a preprint in 2015, has little direct empirical support, and has never been published in a peer reviewed journal.
Another group has reported that "age spots" taken from human skin biopsies of patients facial senile lentigo of Fitzpatrick skin type III or IV aged 55–62 are enriched with senescent fibroblasts compared to surrounding skin. The dark coloration appeared to be due to higher melanin levels and activity of tyrosinase in the senescent fibroblasts than in the controls, potentially related to lower SDF1 expression. Patients were then administered six weekly treatments of microneedle fractional radiofrequency aimed at eliminating dermal senescent fibroblasts; this led to a marked decrease in epidermal pigmentation compared to baseline, accompanied by a decrease in the synthesis of collagen and the normalization of suppressed SDF1 expression.
Treatment
Treatment for liver spots is almost never done for health-related reasons, though it is sometimes done for cosmetic ones. Skin-bleaching products that inhibit pigmentation or cosmetic creams containing the ingredients alpha hydroxy acids or retinoids are known to be effective. Liver spots can also be frozen off with liquid nitrogen; that is, via cryosurgery.
See also
Freckle
Lentigo
List of cutaneous conditions
References
External links
External signs of ageing
Melanocytic nevi and neoplasms
Human skin color | Liver spot | [
"Biology"
] | 766 | [
"Senescence",
"Human skin color",
"External signs of ageing",
"Pigmentation"
] |
4,286,589 | https://en.wikipedia.org/wiki/Quarry-faced%20stone | Quarry-faced stone is a stone with a rough, unpolished surface, straight from the quarry.
References
Building stone
Building materials
Natural materials
Stone (material) | Quarry-faced stone | [
"Physics",
"Engineering"
] | 34 | [
"Natural materials",
"Building engineering",
"Construction",
"Materials",
"Building materials",
"Matter",
"Architecture"
] |
4,286,922 | https://en.wikipedia.org/wiki/Glass-ceramic-to-metal%20seals | A glass-ceramic-to-metal seal is a type of mechanical seal which binds glass-ceramic and metal surfaces. They are related to glass-to-metal seals, and like them are hermetic (airtight).
Properties
Glass-ceramics are polycrystalline ceramic materials prepared by the controlled crystallization of suitable glasses, normally silicates. Depending on the starting glass composition and the heat-treatment schedule adopted, glass-ceramics can be prepared with tailored thermal expansion characteristics. This makes them ideal for sealing to a variety of different metals, ranging from low expansion tungsten (W) or molybdenum (Mo) to high expansion stainless steels and nickel-based superalloys.
Glass-ceramic-to-metal seals offer superior properties over their glass equivalents including more refractory behaviour, in addition to their ability to seal successfully to many different metals and alloys. They have been used in electrical feed-through seals for such applications as vacuum interrupter envelopes and pyrotechnic actuators, in addition to many applications where a higher temperature capability than is possible with glass-to-metal seals is required, including solid oxide fuel cells.
Process
In the formation of a glass-ceramic-to-metal seal, the parts to be joined are first heated, normally under inert atmosphere, in order to melt the glass and allow it to wet and flow into the metal parts, in much the same way as when preparing a more conventional glass-to-metal seal. The temperature is then normally reduced into a temperature regime where many microscopic nuclei are formed in the glass. The temperature is then raised again into a regime where the major crystalline phases can form and grow to create the polycrystalline ceramic material with thermal expansion characteristics matched to that of the particular metal parts.
Examples
The white opaque "glue" between the panel and the funnel of a colour TV cathode ray tube is a
devitrified solder glass based on the system ––. While
this is a glass-ceramic-to-glass seal, the basic patent of S.A. Claypoole considers
glass-ceramic-to-metal seals as well.
References
(devitrified solder glass)
Seals (mechanical)
Industrial processes
Glass applications
Glass compositions
Glass engineering and science
Glass-ceramics | Glass-ceramic-to-metal seals | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 469 | [
"Seals (mechanical)",
"Glass chemistry",
"Glass engineering and science",
"Glass compositions",
"Materials science",
"Materials",
"Matter"
] |
4,287,020 | https://en.wikipedia.org/wiki/Poisson%20ring | In mathematics, a Poisson ring is a commutative ring on which an anticommutative and distributive binary operation satisfying the Jacobi identity and the product rule is defined. Such an operation is then known as the Poisson bracket of the Poisson ring.
Many important operations and results of symplectic geometry and Hamiltonian mechanics may be formulated in terms of the Poisson bracket and, hence, apply to Poisson algebras as well. This observation is important in studying the classical limit of quantum mechanics—the non-commutative algebra of operators on a Hilbert space has the Poisson algebra of functions on a symplectic manifold as a singular limit, and properties of the non-commutative algebra pass over to corresponding properties of the Poisson algebra.
Definition
The Poisson bracket must satisfy the identities
(skew symmetry)
(distributivity)
(derivation)
(Jacobi identity)
for all in the ring.
A Poisson algebra is a Poisson ring that is also an algebra over a field. In this case, add the extra requirement
for all scalars s.
For each g in a Poisson ring A, the operation defined as is a derivation. If the set generates the set of derivations of A, then A is said to be non-degenerate.
If a non-degenerate Poisson ring is isomorphic as a commutative ring to the algebra of smooth functions on a manifold M, then M must be a symplectic manifold and is the Poisson bracket defined by the symplectic form.
References
Ring theory
Symplectic geometry | Poisson ring | [
"Mathematics"
] | 331 | [
"Fields of abstract algebra",
"Ring theory"
] |
4,287,403 | https://en.wikipedia.org/wiki/Dishwasher%20salt | Dishwasher salt is a particular grade of granulated, crystalline sodium chloride intended for regenerating the water softener circuit of household or industrial dishwashers. Analogous to water softener salt, dishwasher salt regenerates ion exchange resins, expelling the therein trapped calcium and magnesium ions that characterize hard water. Dishwater salt granules are larger than those of table salt. The granule size ensures that the salt dissolves slowly, and that fine particles do not block the softener unit.
Dishwasher salt is unsuitable for cooking as it is not considered food grade and therefore may contain toxic elements.
In some countries, especially those in Europe, dishwashers include a built-in water softener that removes calcium and magnesium ions from the water. Dishwasher salt, which is coarse-grained sodium chloride (table salt), is used to regenerate the resin in the built-in ion-exchange system. The coarse grains prevent it from clogging the softener unit. Unlike certain types of salt used for culinary purposes, it does not contain added anticaking agents or magnesium salts. The presence of magnesium salts will defeat the purpose of removing magnesium from the water softener. Anticaking agents may lead to clogging or may contain magnesium. Table salt may contain added iodine in the form of sodium iodide or potassium iodide. These compounds will not affect the ion-exchange system, but adding table salt to the dishwasher's water softening unit can damage it.
If a dishwasher has a built-in water softener there will be a special compartment inside the dishwasher where the salt is to be added when needed. This salt compartment is separate from the detergent compartment, and generally located at the bottom of the wash cabinet (this is below the bottom basket). On most dishwashers, an automatic sensing system will notify the user when more dishwasher salt is required.
If the dishwasher has run out of the salt that regenerates the ion exchange resin that softens the water, and the water supply is "hard", limescale deposits can appear on all items, but are especially visible on glassware.
In areas with soft water there is no need to use dishwasher salt for the machine to work. There is an option to adjust the water hardness making the machine to use no amount of salt brine for every dish cycle.
References
Water technology
Dishwashing | Dishwasher salt | [
"Chemistry"
] | 509 | [
"Water technology",
"Inorganic compounds",
"Inorganic compound stubs"
] |
4,287,465 | https://en.wikipedia.org/wiki/Inclusive%20language | Inclusive language is a language style that seeks to avoid expressions that its proponents perceive as expressing or implying ideas that are sexist, racist, or otherwise biased, prejudiced, or insulting to particular group(s) of people; and instead uses language intended by its proponents to avoid offense and fulfill the ideals of egalitarianism, social inclusion and equity. Its aim is bias-free communication, that attempts to be equally inclusive of people of all ethnicities, gender identities, sexual orientations, religious affiliations, abilities, and ages by communicating in a way that makes no assumptions about the receiver of such communication.
Its supporters argue that language is often used to perpetuate and spread prejudice and that creating intention around using inclusive language can help create more productive, safe, and profitable organizations and societies. The term "political correctness" is sometimes used to refer to this practice, either as a neutral description by supporters, by commentators in general, or with negative connotations by its opponents. Use of gender-neutral terminology has been controversial in languages where "all grammar is gendered", such as Spanish, French, Italian, Portuguese, and German; some areas have banned its use.
Inclusive language is usually adopted by following a language guide that lists words and expression not to use and substitutes for them. Language guides are used by many organizations, especially non-profits (at least in the United States).
Bias
An important part of communicating in a bias-free manner is by making sure to engaging in meaningful conversations using bias-free language. The writer's word choice is vital in terms of effectively communicating in ways that do not offend the receiver. According to Locker, "Bias-free language is language that is sensitive to people's sex, race, age, physical condition and many other categories. Bias-free language does not discriminate and therefore includes all readers in a fair and friendly manner."
Bias exists everywhere, even if it is not always acknowledged. If a verbal or written communication includes any of the following, it may be biased:
Unsupported claims.
Extreme or inappropriate language.
For written text, there may be no clear author.
Spoken communication may have a speaker with a poor reputation.
These sources should be questioned for their bias because it could impact their validity in their points. Therefore, avoiding bias in all communication will ensure that the point is crystal clear and the speaker is trusted.
Scope
France
In French, a reference to a mixed-gender group of friends would traditionally be written as "amis", but a gender-neutral variation changed its spelling to "ami·e·s." However, in May 2021, the Minister for Education wrote to schools across the country to say that "so-called 'inclusive' writing should be avoided, which notably uses the midpoint to simultaneously reveal the feminine and masculine forms of a word used in the masculine when it is used in a generic sense."
Argentina
As of June 2022, the city government of Buenos Aires, the capital of Argentina, banned teachers "from using any gender-neutral words during class and in communications with parents", on the grounds that it "violated the rules of Spanish and stymied students' reading comprehension". At least five organizations, "a mix of gay rights and civil rights groups", have filed lawsuits seeking to overturn" the ruling. The governor of Buenos Aires province, Axel Kicillof, rejected the authority of the Royal Spanish Academy, citing the Argentine War of Independence as a reason. Darío Villanueva Prieto, from the RAE, clarified that the RAE does not use the slang of Spanish language from the Iberian peninsula, but that it receives input from all countries in the world where the language is spoken.
Uruguay
In December 2021, Uruguay's public education agency issued a memo to limit use of inclusive language.
United States
Organizations in the U.S. with equity language guides include The Sierra Club, American Cancer Society, American Heart Association, American Medical Association, National Recreation and Park Association, Columbia University School of Professional Studies, University of Washington. According to George Packer, most of these guides are based on other guides such as A Progressive's Style Guide, the Racial Equity Tools glossary, and others.
Several tech companies promotes or provide inclusive language guides: Google, Apple, Microsoft, IBM, Cisco Talos, SAP.
Examples
English
Inclusive language in English, at least in the United States, goes well beyond gender inclusivity, the following with varying levels or usage.
Impact
Inclusion and divisiveness
Political correctness and inclusive language both focus on attempting to use neutral terms and expressions to influence psychological and social forces to combat prejudices, stereotypes, etc. However, what may be, and in many cases already has, happened is that while some markets and audiences embrace the new language, others react against it (an example being the alleged "War on Christmas"). Whether businesses and organizations embrace or reject the language, they risk alienating the opposing side. Thus inclusive language has become part of "culture wars".
Other concerns
Journalist George Packer makes a number of criticisms of inclusive language as used in the U.S.
Replacing vivid language with jargon, while failing to deliver on its goal of creating empathy
Packer compares a passage from Behind the Beautiful Forevers by Katherine Boo with the same text rewritten in inclusive language, and asks if equity language does "what it claims to do" -- i.e. create more empathy for Sita and her struggles than Boo does in her language use.
Packer notes that Boo's book was written in 2012 before the new language guidelines emerged, and worries what the new rules will and are doing to good writing. "Shelf upon shelf of great writing might go the way of 'blind' and 'urban'" (both forbidden in language guideline). "Open Light in August or Invisible Man to any page and see how little would survive."
Banning not only offensive language, but more and more harmless words and expressions.
Using the Sierra Club equity guidelines, Packer notes that it is not just terms like "welfare queen", or expressions like "Jew them down" that are banished, but a very large number of descriptive terms: "urban", "vibrant", "hardworking", "brown bag" (subtly racist) "the poor" (classist), "battle" and "minefield" (disrespectful of veterans), "field" or "fieldwork" (could be associated with slavery), "migrant" (no reason given). Others include "prisoner" (replaced by "a person experiencing the criminal-justice system"), "gentrification", "legal resident", "food stamps", "gun control", "congresswoman", and "expat".
Imprecise
Replacing "felon" with "justice-involved person" (the San Francisco Board of Supervisors); "fieldwork" with "practicum" (the Southern California's School of Social Work). Imprecise, unclear language has the advantage of being "less likely to offend", whereas "vivid imagery, strong statements" -- what makes up good writing -- "convey painful truths".
Elitist
The language guides defend their edicts of inclusive language by arguing language is always changing, "evolving". But inclusive language has not "emerged organically from the shifting linguistic habits of large numbers of people" or even public debate. Its changes "are handed down in communiqués written by obscure 'experts' who purport to speak for vaguely defined 'communities'".
And not only do the changes come without any transparent discussion, they come "with a suddenness and frequency that keep the novitiate off-balance".
An American-led project, and serves as a substitute for actual "material forms of progress" to help those it purports to help.
By toning down (or attempting to tone down) harsh language, inclusive language may make it easier to avoid facing "squarely the wrongs they want to right, which is the starting point for any change".
From a jumping-off point of a The Lancet quote specifying "bodies with vaginas have been neglected" rather than "cisgender women," a NLM study claims that rather than mere elaboration to specify a subset of women in order to be more accommodating of people who identify as transgender, this is "desexing language when describing female reproduction" and represents the broader "avoidance of sexed terms" such as "mothers." Hence, engaging in language alteration when the sex of the person is relevant risks "decreasing overall inclusivity; dehumanizing; including people who should be excluded; being imprecise, inaccurate or misleading; and disembodying and undermining breastfeeding."
See also
Bias-free communication
Cancel culture
Color-blind casting
Communication rights
Euphemism
List of politically motivated renamings
Newspeak
Plain language
Speech code
Stereotypes
References
External links
Guidelines for Unbiased Language (PDF Table) from APA Style manual
'Allistic' Cambridge Dictionary
Inclusive Naming Initiative
United Nations, Gender inclusive language
Linguistic controversies
Political terminology
Dysphemisms
Etiquette
Identity politics
Gender-neutral language
Discrimination
Social inclusion | Inclusive language | [
"Biology"
] | 1,902 | [
"Behavior",
"Aggression",
"Discrimination",
"Etiquette",
"Human behavior"
] |
4,287,527 | https://en.wikipedia.org/wiki/Arlene%20Blum | Arlene Blum (born March 1, 1945) is an American mountaineer, writer, and environmental health scientist. She is best known for leading the first successful American ascent of Annapurna (I), a climb that was also an all-woman ascent. She led the first all-woman ascent of Denali ("Denali Damsels" expedition), and was the first American woman to attempt Mount Everest. She is executive director of the Green Science Policy Institute, an organization of scientists who develop and communicate peer-reviewed research to develop innovative solutions to reduce the use of toxic chemicals.
Early life
Blum was born in Davenport, Iowa, and raised from the age of five on in Chicago by her Orthodox Jewish grandparents and mother. In the early 1960s, she attended Reed College in Portland, Oregon. Her first climb was in Washington, where she failed to reach the summit of Mount Adams. However, she persevered, climbing throughout her college and graduate school days. She was rejected from an Afghanistan expedition in 1969, with its leader writing to her, "One woman and nine men would seem to me to be unpleasant high on the open ice, not only in excretory situations but in the easy masculine companionship which is so vital a part of the joy of an expedition." However, she had been able to go climbing as part of her research for her senior thesis, which was on the topic of volcanic gases on Oregon's Mount Hood. In her thesis she predicted that one of the Pacific northwest volcanoes would soon erupt with devastating violence, and 14 years later Mt. St. Helens did have a violent eruption. Blum graduated from Reed in 1966 and attended MIT and UC Berkeley, where she earned a PhD in biophysical chemistry in 1971. After graduate school, Blum embarked on what she called the "Endless Winter" – spending more than a year climbing peaks all over the world.
Major climbs
In 1969, she applied to join an expedition to Denali in Alaska, and was told that women were welcome to come only as far as the base camp to "help with the cooking." Blum then organized and co-led the first all-woman team to ascend Denali in 1970. Blum participated in the second American effort to climb Mount Everest as part of the American Bicentennial Everest Expedition, but did not reach the summit. In 1978, she organized a team of eleven women to climb the tenth highest mountain in the world, Annapurna (I) in Nepal which, until then, had been climbed by only eight people (all men). It was called American Women's Himalayan Expeditions – Annapurna. They raised money for the trip in part by selling T-shirts with the slogan "A woman's place is on top". The first summit team, comprising Vera Komarkova and Irene Miller (now Beardsley) and Sherpas Mingma Tsering and Chewang Ringjing, reached the top at 3:30 p.m. on October 15, 1978. The second summit team, Alison Chadwick-Onyszkiewicz and Vera Watson, died during their climb. After the event, Blum wrote a book about her experience on Annapurna, called Annapurna: A Woman's Place.
She led the first expedition to climb Bhrigupanth in the Indian Himalayas, leading a team of Indian and American women. She then made what she called the "Great Himalayan Traverse", a two-thousand-mile journey adjacent to beautiful peaks of the Himalayas from Bhutan to India with treker Hugh Swift. She and her partner Rob Gomersall crossed the Alps from Yugoslavia to France, bearing their baby Annalise in a backpack.
Early scientific work
As a graduate student at UC Berkeley, Blum predicted the correct three-dimensional structure for transfer RNA, an essential building block in all organisms, by stringing hippie beads for the nine known tRNA sequences in four colors to represent the four nucleic acid bases, pairing the bases, and folding them into a logical structure.
While a post doc in the Stanford biochemistry department, she discovered the first physical evidence for intermediate states in the folding of protein molecules doing "temperature jump NMR," a technique she imagined while watching water melting from a glacier in Central Asia. Her Stanford advisor, Robert Baldwin, stated in his oral history that this work was a first step towards solving the problem of the mechanism of protein folding.
Blum's research with biochemist Bruce Ames at the UC Berkeley found that the flame retardant called Tris, used at high levels in most children's pajamas in the middle of the 1970s, was a mutagen and likely carcinogen. Three months after their 1977 paper in Science was published, children's sleepwear containing Tris was banned in the United States.
Science policy work
After a 26-year long hiatus, Blum returned to science and policy work in 2006—when her daughter started college—and her memoir Breaking Trail: A Climbing Life was published. She discovered that the same Tris her research had helped remove from children's pajamas was back in American couches and baby products.
As a result, Blum founded the Green Science Policy Institute (GSP) in 2007 to bring scientific research results to decision makers in government and industry to protect human health and the environment from toxic chemicals. Blum and her team collaborate with scientists on policy-relevant research projects and translate scientific information to educate decision makers, the press, and the public. The Institute's work has contributed to many policies and business practices that reduce the use of toxic chemicals, particularly halogenated chemicals such as flame retardants, antimicrobials, and per- and polyfluoroalkyl substances (PFAS).
Writing
Her first book, Annapurna: A Woman's Place was included in Fortune Magazine's 2005 list of "The 75 Smartest Business Books We Know" and chosen by National Geographic Adventure Magazine as one of the 100 top adventure books of all time. Her award-winning memoir, Breaking Trail: A Climbing Life tells the story of how Blum realized improbable dreams among the world's highest mountains, in the chemistry laboratory, and in public policy.
Blum has published articles about science policy in The New York Times, Science magazine, Los Angeles Times, and The Huffington Post.
Awards and other activities
For her mountaineering accomplishments, Blum was the winner of the Sierra Club's Francis P. Farquhar Mountaineering Award for 1982. She holds a Gold Medal from the Society of Woman Geographers, an honor previously given to only eight other women including Amelia Earhart, Margaret Mead, and Mary Leakey. The American Alpine Club inducted Blum into its Hall of Mountaineering Excellence in 2012.
For her science and policy work, Blum won the Purpose Prize in 2008, an award for those over 60 who are solving society's greatest problems. In 2010, the National Women's History Project selected her as one of "100 Women Taking the Lead to Save Our Planet." In 2014 she was inducted into the Alameda County Women's Hall of Fame for Science, Engineering and Technology and received the Benjamin Ide Wheeler Medal as the city of Berkeley's "most useful citizen." In 2015, her alma mater Reed College awarded her the Thomas Lamb Eliot Award for Lifetime Achievement. In 2018 Blum was inducted into the California Hall of Fame. In 2022, she was granted an honorary doctorate by the University of San Francisco. 2024 Blum was recognized as one of 50 Forbes Sustainability Leaders.
Arlene Blum is the founder of the annual Berkeley Himalayan Fair and the Burma Village Assistance Project. She serves on the board of the Plastic Pollution Coalition.
Quotes
"With a global and virtual expedition team, we are attempting challenging and important mountains and reaching for the summit of a healthier world to benefit us all."
"The health and environmental problem from such chemicals could be as threatening as climate change, but I believe it is a problem that can be solved relatively easily. It's a matter of informing the public – and political will."
"My new adventure in science and policy work is the most challenging and important of my life and I feel lucky to look out at the horizon and see endless rows of mountains to climb."
"In America, foods, drugs and pesticides are regulated, you may say they are not well enough regulated, but you really have to provide information because those are the things that go into our mouths. Other chemicals like flame retardants are not regulated, there are not really health requirements but they go into our bodies the same way."
Personal life
Blum lives and works in Berkeley, California. She has a daughter, Annalise Blum, a 2010 graduate of Stanford University in environmental engineering. In 2017 Annalise earned a Ph.D. in Civil Engineering at Tufts University. In March, 2023, Annalise was appointed Deputy Assistant Secretary for Water and Science in the U.S. Department of the Interior.
References
External links
Arlene Blum official website
Green Science Policy Institute website
Purpose Prize Profile
Article about Arlene Blum in Reed College Magazine
Interview with Arlene Blum for Breaking Trail
Dashka Slater, "Arlene Blum's Crusade Against Household Toxins", The New York Times, September 9, 2012.
California Museum profile
Reed College alumni
Massachusetts Institute of Technology alumni
UC Berkeley College of Chemistry alumni
Living people
1945 births
American mountain climbers
American female climbers
American environmental scientists
American non-fiction environmental writers
Jewish American non-fiction writers
Sportspeople from Berkeley, California
Writers from Berkeley, California
Activists from California
Sierra Club awardees
Members of the Society of Woman Geographers
American women scientists
American scientists
American women non-fiction writers
21st-century American Jews
21st-century American women
20th-century American sportswomen | Arlene Blum | [
"Environmental_science"
] | 2,011 | [
"American environmental scientists",
"Environmental scientists"
] |
4,287,778 | https://en.wikipedia.org/wiki/Hydrometeorology | Hydrometeorology is a branch of meteorology and hydrology that studies the transfer of water and energy between the land surface and the lower atmosphere for academic research, commercial gain or operational forecasting purposes.
Whilst traditionally meteorologists and hydrologists sit within separate organisations, hydrometeorlogists may work in joint project teams, virtual teams, deal with specific incidents or be permanently co-located to deliver specific objectives. Hydrometeorlogists typically have a foundation in one or other discipline before undertaking additional training and specialist forecaster training depending on requirements. The cross over skills and knowledge between the two disciplines can bring organisational benefits in terms of efficiencies in terms of using tools and data available, and provide benefits in terms of enhanced lead times ahead of hydrometeological hazards occurring.
UNESCO has several programs and activities in place that deal with the study of natural hazards of hydrometeorological origin and the mitigation of their effects. Among these hazards are the results of natural processes and atmospheric, hydrological, or oceanographic phenomena such as floods, tropical cyclones, drought, and desertification. Many countries have established an operational hydrometeorological capability to assist with forecasting, warning, and informing the public of these developing hazards.
Hydrometeorological forecasting
One of the more significant aspects of hydrometeorology involves predictions about and attempts to mitigate the effects of high precipitation events. There are three primary ways to model meteorological phenomena in weather forecasting, including nowcasting, numerical weather prediction, and statistical techniques. Nowcasting is good for predicting events a few hours out, utilizing observations and live radar data to combine them with numerical weather prediction models. The primary technique used to forecast weather, numerical weather prediction uses mathematical models to account for the atmosphere, ocean, and many other variables when producing forecasts. These forecasts are generally used to predict events days or weeks out. Finally, statistical techniques use regressions and other statistical methods to create long-term projections that go out weeks and months at a time. These models allow scientists to visualize how a multitude of different variables interact with one another, and they illustrate one grand picture of how the Earth's climate interacts with itself.
Risk assessment
A major component of hydrometeorology is mitigating the risk associated with flooding and other hydrological threats. First, there has to be knowledge of the possible hydrological threats that are expected within a specific region. After analyzing the possible threats, warning systems are put in place to quickly alert people and communicate to them the identity and magnitude of the threat. Many nations have their own specific regional hydrometeorological centers that communicate threats to the public. Finally, there must be proper response protocols in place to protect the public during a dangerous event.
Operational hydrometeorology in practice
Countries with a current operational hydrometeorological service include, among others:
Australia (Bureau of Meteorology)
Brazil (National Center for Natural Disaster Monitoring and Alerts)
Canada (Environment Canada)
England and Wales (Flood Forecasting Centre)
France
Germany
India
Scotland (Flood Forecasting Service)
Serbia (Republic Hydrometeorological Service of Serbia)
Russia (Hydrometeorological Centre of Russia)
United States (Hydrometeorological Prediction Center, known as the Weather Prediction Center since 2013)
References
External links
World Meteorological Organization – List of national hydrological and hydrometeorological services
Hydrology
Branches of meteorology
Oceanography | Hydrometeorology | [
"Physics",
"Chemistry",
"Engineering",
"Environmental_science"
] | 705 | [
"Oceanography",
"Hydrology",
"Applied and interdisciplinary physics",
"Environmental engineering"
] |
4,288,722 | https://en.wikipedia.org/wiki/Reciprocating%20Chemical%20Muscle | The reciprocating chemical muscle (RCM) is a mechanism that takes advantage of the superior energy density of chemical reactions. It is a regenerative device that converts chemical energy into motion through a direct noncombustive chemical reaction.
Function
RCM is capable of generating autonomic wing beating from a chemical energy source. It can also be used to provide a small amount of electricity to the onboard control systems. It further helps in differential lift enhancement on the wings to achieve roll, pitch, and hence, steered flight. The RCM technique is particularly useful in the manufacturing of insect-like micro air vehicles. The first generation of RCMs was large and had a reciprocating frequency around 10 Hz. The later generations developed were very much smaller and lighter. Also, the reciprocating frequency of this generation RCM was as high as 60 Hz. The reciprocating chemical muscle was invented by Prof. Robert C. Michelson of the Georgia Tech Research Institute and implemented up through its fourth generation by Nino Amarena of ETS Laboratories.
Benefits
Particular benefits of the RCM are:
It requires no ignition source (thereby allowing it to work in explosive atmospheres).
It is independent of external oxidant (thereby allowing it to operate under water or in oxygen-free environments such as the lower atmosphere of the planet Mars).
It thermoelectrically generates electrical energy from its own exothermic metabolism.
It converts chemical potential energy directly into kinetic energy with greater energy density than batteries.
Mechanism
The reciprocating chemical muscle uses various monopropellants in the presence of specific catalysts to create gas from a liquid without combustion. This gas is used to drive reciprocating opposing cylinders (in the fourth-generation device) to produce sufficient motion (throw) with sufficient force and frequency to allow flapping-wing flight. As of 2004, the RCM had been demonstrated in the Georgia Tech Research Institute laboratory to achieve sufficient throw, force, and frequency for operation of a 50-gram entomopter while using high concentration (> 90%) hydrogen peroxide in the presence of a proprietary catalyst developed by ETS Laboratories.
Specific uses
The reciprocating chemical muscle was developed as a drive mechanism for the flapping wings of the entomopter. The RCM reuses energy many times before releasing it into its surroundings. First, it converts mainly heat energy into flapping-wing motion in the entomopter. Then, heat is scavenged for thermoelectric generation in support of ancillary systems. Waste gas from the chemical decomposition of the fuel is then used to create a frequency modulated continuous wave acoustic ranging signal that is Doppler insensitive (used for obstacle avoidance). Waste gas is then passed through an ejector to entrain external atmospheric gases to increase mass flow and decrease waste gas temperature so that lower-temperature components can be used downstream. Some waste gas is diverted into gas bearings for rotational and linear moving components. Finally, remaining waste gas is vectored into the wings where it is used for circulation-controlled lift augmentation (Coanda effect). Any remaining gas can be used for vectored thrust, but if the gas budgets are correctly designed, there should be no extra gas beyond the circulation control points. The features of the RCM are tailored to the entomopter to conserve energy.
Patents
U.S. Patent No. 6,446,909, September 10, 2002, “Reciprocating Chemical Muscle (RCM) and Method for Using Same”
References
External links
Robert C. Michelson: Entomopter Project
Engines | Reciprocating Chemical Muscle | [
"Physics",
"Technology"
] | 749 | [
"Physical systems",
"Machines",
"Engines"
] |
3,145,000 | https://en.wikipedia.org/wiki/Subframe | A subframe is a structural component of a vehicle, such as an automobile or an aircraft, that uses a discrete, separate structure within a larger body-on-frame or unibody to carry specific components like the powertrain, drivetrain, and suspension. The subframe is typically bolted or welded to the vehicle. When bolted, it often includes rubber bushings or springs to dampen vibrations.
The primary purposes of using a subframe are to distribute high chassis loads over a wide area of relatively thin sheet metal of a monocoque body shell and to isolate vibrations and harshness from the rest of the body. For example, in an automobile with its powertrain contained in a subframe, forces generated by the engine and transmission can be sufficiently damped to prevent disturbing the passengers. Modern vehicles use separate front and rear subframes to reduce overall weight and cost while maintaining structural integrity. Additionally, subframes benefit production by allowing subassemblies to be created and later introduced to the main body shell on an automated line.
There are generally three basic forms of the subframe:
A simple "axle" type, which usually supports the lower control arms and steering rack.
A perimeter frame, which supports the lower control arms, steering rack, and engine.
A perimeter frame with full support, which supports the lower control arms, steering rack, engine, transmission, and possibly the full suspension, commonly used in front-wheel-drive cars.
Subframes are typically made of pressed steel panels that are thicker than body shell panels and are welded or spot-welded together. Hydroformed tubes may also be used in some designs.
The revolutionary monocoque, transverse-engined, front-wheel-drive 1959 Austin Mini set the template for modern front-wheel-drive cars by using front and rear subframes to provide accurate road wheel control while maintaining a stiff, lightweight body. The 1961 Jaguar E-Type (XKE) used a tubular space frame–type front subframe to mount the engine, gearbox, and long bonnet/hood to a monocoque "tub" passenger compartment. Beginning with the 1960s, subframes saw regular production with General Motors' X- and F-platform bodies, and the Astro/Safari mid-size vans.
Subframes are prone to misalignment, which can cause vibration and alignment issues in the suspension and steering components. Misalignment is caused by space between the mounting bolts and the mounting hole. Several companies in the automotive aftermarket, including TyrolSport in the US and Spoon Sports in Japan, offer solutions for subframe misalignment and movement issues.
References
Automotive chassis types
Auto parts
Structural system
Structural engineering | Subframe | [
"Technology",
"Engineering"
] | 544 | [
"Structural engineering",
"Building engineering",
"Structural system",
"Construction",
"Civil engineering"
] |
3,145,218 | https://en.wikipedia.org/wiki/Separation%20of%20duties | Separation of duties (SoD), also known as segregation of duties, is the concept of having more than one person required to complete a task. It is an administrative control used by organisations to prevent fraud, sabotage, theft, misuse of information, and other security compromises. In the political realm, it is known as the separation of powers, as can be seen in democracies where the government is separated into three independent branches: a legislature, an executive, and a judiciary.
General description
Separation of duties is a key concept of internal controls. Increased protection from fraud and errors must be balanced with the increased cost/effort required.
In essence, SoD implements an appropriate level of checks and balances upon the activities of individuals. R. A. Botha and J. H. P. Eloff in the IBM Systems Journal describe SoD as follows.
Separation of duty, as a security principle, has as its primary objective the prevention of fraud and errors. This objective is achieved by disseminating the tasks and associated privileges for a specific business process among multiple users. This principle is demonstrated in the traditional example of separation of duty found in the requirement of two signatures on a cheque.
Actual job titles and organizational structure may vary greatly from one organization to another, depending on the size and nature of the business. Accordingly, rank or hierarchy are less important than the skillset and capabilities of the individuals involved. With the concept of SoD, business critical duties can be categorized into four types of functions: authorization, custody, record keeping, and reconciliation. In a perfect system, no one person should handle more than one type of function.
Principles
Principally several approaches are optionally viable as partially or entirely different paradigms:
sequential separation (two signatures principle)
individual separation (four eyes principle)
spatial separation (separate action in separate locations)
factorial separation (several factors contribute to completion)
Auxiliary Patterns
A person with multiple functional roles has the opportunity to abuse those powers. The pattern to minimize risk is:
Start with a function that is indispensable, but potentially subject to abuse.
Divide the function into separate steps, each necessary for the function to work or for the power that enables that function to be abused.
Assign each step to a different person or organization.
General categories of functions to be separated:
authorization function
recording function, e.g. preparing source documents or code or performance reports
custody of asset whether directly or indirectly, e.g. receiving checks in mail or implementing source code or database changes.
reconciliation or audit
splitting one security key in two (more) parts between responsible persons
Primarily the individual separation is addressed as the only selection.
Application in general business and in accounting
The term SoD is already well known in financial accounting systems. Companies in all sizes understand not to combine roles such as receiving cheques (payment on account) and approving write-offs, depositing cash and reconciling bank statements, approving time cards and have custody of pay cheques, etc. SoD is fairly new to most Information Technology (IT) departments, but a high percentage of Sarbanes-Oxley internal audit issues come from IT.
In information systems, segregation of duties helps reduce the potential damage from the actions of one person. IS or end-user department should be organized in a way to achieve adequate separation of duties. According to ISACA's Segregation of Duties Control matrix, some duties should not be combined into one position. This matrix is not an industry standard, just a general guideline suggesting which positions should be separated and which require compensating controls when combined.
Depending on a company's size, functions and designations may vary. Smaller companies with a lack of SoD typically face concerns in disbursement cycles where unauthorized purchases and payments can occur. When duties cannot be separated, compensating controls should be in place. Compensating controls are internal controls that are intended to reduce the risk of an existing or potential control weakness. If a single person can carry out and conceal errors and/or irregularities in the course of performing their day-to-day activities, they have been assigned SoD incompatible duties. There are several control mechanisms that can help to enforce the segregation of duties:
Audit trails enable IT managers or Auditors to recreate the actual transaction flow from the point of origination to its existence on an updated file. Good audit trails should be enabled to provide information on who initiated the transaction, the time of day and date of entry, the type of entry, what fields of information it contained, and what files it updated.
Reconciliation of applications and an independent verification process is ultimately the responsibility of users, which can be used to increase the level of confidence that an application ran successfully.
Exception reports are handled at supervisory level, backed up by evidence noting that exceptions are handled properly and in timely fashion. A signature of the person who prepares the report is normally required.
Manual or automated system or application transaction logs should be maintained, which record all processed system commands or application transactions.
Supervisory review should be performed through observation and inquiry.
To compensate mistakes or intentional failures by following a prescribed procedure, independent reviews are recommended. Such reviews can help detect errors and irregularities.
Application in information systems
The accounting profession has invested significantly in separation of duties because of the understood risks accumulated over hundreds of years of accounting practice.
By contrast, many corporations in the United States found that an unexpectedly high proportion of their Sarbanes-Oxley internal control issues came from IT. Separation of duties is commonly used in large IT organizations so that no single person is in a position to introduce fraudulent or malicious code or data without detection. Role-based access control is frequently used in IT systems where SoD is required. More recently, as the number of roles increases in a growing organization, a hybrid access control model with Attribute-based access control is used to resolve the limitations of its role-based counterpart.
Strict control of software and data changes will require that the same person or organizations performs only one of the following roles:
Identification of a requirement (or change request); e.g. a business person
Authorization and approval; e.g. an IT governance board or manager
Design and development; e.g. a developer
Review, inspection and approval; e.g. another developer or architect.
Implementation in production; typically a software change or system administrator.
This is not an exhaustive presentation of the software development life cycle, but a list of critical development functions applicable to separation of duties.
To successfully implement separation of duties in information systems a number of concerns need to be addressed:
The process used to ensure a person's authorization rights in the system is in line with his role in the organization.
The authentication method used such as knowledge of a password, possession of an object (key, token) or a biometrical characteristic.
Circumvention of rights in the system can occur through database administration access, user administration access, tools which provide back-door access or supplier installed user accounts. Specific controls such as a review of an activity log may be required to address this specific concern.
References
External links
Nick Szabo's essay on
"Segregation/separation of duties definition", ISACA
"Segregate Duties to Lessen Security Risks", Datamation
"Transparency, Partitioning, Separation, Rotation and Supervision of Responsibilities", ISM3
Auditing terms
Data security | Separation of duties | [
"Engineering"
] | 1,495 | [
"Cybersecurity engineering",
"Data security"
] |
3,145,356 | https://en.wikipedia.org/wiki/Pose%20%28computer%20vision%29 | In the fields of computing and computer vision, pose (or spatial pose) represents the position and the orientation of an object, each usually in three dimensions. Poses are often stored internally as transformation matrices. The term “pose” is largely synonymous with the term “transform”, but a transform may often include scale, whereas pose does not.
In computer vision, the pose of an object is often estimated from camera input by the process of pose estimation. This information can then be used, for example, to allow a robot to manipulate an object or to avoid moving into the object based on its perceived position and orientation in the environment. Other applications include skeletal action recognition.
Pose estimation
The specific task of determining the pose of an object in an image (or stereo images, image sequence) is referred to as pose estimation. Pose estimation problems can be solved in different ways depending on the image sensor configuration, and choice of methodology. Three classes of methodologies can be distinguished:
Analytic or geometric methods: Given that the image sensor (camera) is calibrated and the mapping from 3D points in the scene and 2D points in the image is known. If also the geometry of the object is known, it means that the projected image of the object on the camera image is a well-known function of the object's pose. Once a set of control points on the object, typically corners or other feature points, has been identified, it is then possible to solve the pose transformation from a set of equations which relate the 3D coordinates of the points with their 2D image coordinates. Algorithms that determine the pose of a point cloud with respect to another point cloud are known as point set registration algorithms, if the correspondences between points are not already known.
Genetic algorithm methods: If the pose of an object does not have to be computed in real-time a genetic algorithm may be used. This approach is robust especially when the images are not perfectly calibrated. In this particular case, the pose represent the genetic representation and the error between the projection of the object control points with the image is the fitness function.
Learning-based methods: These methods use artificial learning-based system which learn the mapping from 2D image features to pose transformation. In short, this means that a sufficiently large set of images of the object, in different poses, must be presented to the system during a learning phase. Once the learning phase is completed, the system should be able to present an estimate of the object's pose given an image of the object.
Camera pose
See also
Gesture recognition
Homography (computer vision)
Camera calibration
Structure from motion
Essential matrix and Trifocal tensor (relative pose)
References
Computer vision
Geometry in computer vision
Robot control | Pose (computer vision) | [
"Mathematics",
"Engineering"
] | 545 | [
"Robotics engineering",
"Packaging machinery",
"Robot control",
"Geometry",
"Artificial intelligence engineering",
"Geometry in computer vision",
"Computer vision"
] |
3,145,455 | https://en.wikipedia.org/wiki/Otto%20Struve%20Telescope | The Otto Struve Telescope was the first major telescope to be built at McDonald Observatory. Located in the Davis Mountains in West Texas, the Otto Struve Telescope was designed by Warner & Swasey Company and constructed between 1933 and 1939 by the Paterson-Leitch Company. Its mirror was the second largest in the world at the time. It was named after the Ukrainian-American astronomer of Baltic German origin Otto Struve in 1966, three years after his death; Struve had been the director of McDonald Observatory from 1932–1950.
The Davis Mountains is an excellent location for astronomical research because of the clear dry air and moderately high elevation. The remote nature of the facility proved to be a significant challenge in transporting such a large mirror. It was a very precarious journey for the Otto Struve Telescope's mirror to this remote part of Texas and up to the top of Mount Locke. The mirror was transported from the local town of Fort Davis up the mountain by Carleton D. Wilson, owner of a local trucking company, while locals cheered as they looked on.
The Otto Struve telescope is still in use today. It is updated with modern imaging detectors allowing astronomers to conduct many types of research.
Noted applications and Discoveries
The telescope was one of two used to set up and define the Johnson-Morgan UBV photometric system.
In 1949, G. Kuiper of Yerkes Observatory discovered a new moon of planet Neptune, named Nereid. The moon was discovered on photographic plates taken in a search for moons of Neptune.
Contemporaries on commissioning
The Otto Struve telescope saw first light in 1939, behind the 100-inch Hooker telescope and ahead of two large British Commonwealth telescopes, both in Canada. Many competing projects were delayed due to the war in the early 1940s.
Four largest telescopes in 1939:
See also
List of largest optical telescopes in the 20th century
List of largest optical reflecting telescopes
List of the largest optical telescopes in the contiguous United States
Notes
References
External links
"Pour Three Ton Telescope Mirror." Popular Science, April 1934, p. 41.
Science: The 82-Inch McDonald Telescope (1939), industrial film capturing the construction and design of the Otto Struve Telescope, Texas Archive of the Moving Image.
Telescopes
University of Texas at Austin | Otto Struve Telescope | [
"Astronomy"
] | 462 | [
"Telescopes",
"Astronomical instruments"
] |
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