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Irene Tracey-Career-Awards and honours In 2008, Tracey was awarded the triennial Patrick Wall Medal from the Royal College of Anaesthetists and in 2009 was made a Fellow of the Royal College of Anaesthetists (FRCA) for her contributions to the discipline. She won the Suffrage Science award in 2014. In 2015 she was elec... | milkshake721/2.1M-wiki-STEM |
Irene Tracey-Career-Publications Tracey has published over 200 original papers; Semantic Scholar lists her as a contributor to over 400 publications including the following publications: Pain 2012 Refresher Courses: 14th World Congress on Pain Pain: A Ladybird Expert Book Wall & Melzack's Textbook of Pain: Expert Consu... | milkshake721/2.1M-wiki-STEM |
Irene Tracey-Personal life-Tracey married the climate physicist Myles Allen in 1994 and has three children. | milkshake721/2.1M-wiki-STEM |
GNAT2-GNAT2-Guanine nucleotide-binding protein G(t) subunit alpha-2 is a protein that in humans is encoded by the GNAT2 gene. | milkshake721/2.1M-wiki-STEM |
GNAT2-Function-Transducin is a 3-subunit guanine nucleotide-binding protein (G protein) which stimulates the coupling of rhodopsin and cGMP-phosphodiesterase during visual impulses. The transducin alpha subunits in rods and cones are encoded by separate genes. This gene encodes the alpha subunit in cones. | milkshake721/2.1M-wiki-STEM |
Gluteal tuberosity-Gluteal tuberosity-The gluteal tuberosity is the lateral one of the three upward prolongations of the linea aspera of the femur, extending to the base of the greater trochanter. It serves as the principal insertion site for the gluteus maximus muscle. | milkshake721/2.1M-wiki-STEM |
Gluteal tuberosity-Structure-The gluteal tuberosity is the lateral prolongation of three prolongations of the linea aspera that extending superior-ward from the superior extremity of the linea aspera on the posterior surface of the femur.The gluteal tuberosity takes the form of either an elongated depression or a rough... | milkshake721/2.1M-wiki-STEM |
Gluteal tuberosity-Structure-Attachments The gluteal tuberosity is the principal site of insertion of the gluteus maximus muscle, accepting the muscle's tendon (the gluteus maximus muscle additionally also inserts onto the iliotibial tract). | milkshake721/2.1M-wiki-STEM |
Computers & Geosciences-Computers & Geosciences-Computers & Geosciences is a scientific journal published monthly by Elsevier on behalf of the International Association for Mathematical Geosciences. It contains research and review papers in computing applied to geosciences. Its impact factor is 3.372. | milkshake721/2.1M-wiki-STEM |
Wilting-Wilting-Wilting is the loss of rigidity of non-woody parts of plants. This occurs when the turgor pressure in non-lignified plant cells falls towards zero, as a result of diminished water in the cells. Wilting also serves to reduce water loss, as it makes the leaves expose less surface area. The rate of loss of... | milkshake721/2.1M-wiki-STEM |
Wilting-Wilting-Lower water availability may result from: drought conditions, where the soil moisture drops below conditions most favorable for plant functioning; the temperature falls to the point where the plant's vascular system cannot function; high salinity, which causes water to diffuse from the plant cells and i... | milkshake721/2.1M-wiki-STEM |
Wilting-Wilting-The plants may recover during the night when evaporation is reduced as the stomata closes.In woody plants, reduced water availability leads to cavitation of the xylem.
Wilting occurs in plants such as balsam and holy basil. Wilting is an effect of the plant growth-inhibiting hormone, abscisic acid.
With... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-COVID-19 pandemic in Venezuela-The COVID-19 pandemic in Venezuela was a part of the worldwide pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first two cases in Venezuela were confirmed on 13 March 2020; the first... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Background-In January, Venezuela's Ministry of Popular Power for Health announced that the Rafael Rangel National Institute of Hygiene (Spanish: Instituto Nacional de Higiene Rafael Rangel) in Caracas would act as the observatory for non-influenza respiratory viruses, including coronaviru... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Timeline-Timeline of 2020 March Venezuela reported its first official cases of coronavirus disease on 13 March 2020. However, several days earlier a suspected case became controversial due to the state treatment of a whistleblower. On 7 March, Fe y Alegría reported that a suspicious medic... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Timeline-April Information Minister Jorge Rodríguez first reported that there were more recoveries than new infections in Venezuela on 11 April. Delcy Rodríguez and Nicolás Maduro announced an extension of the national quarantine and state of alarm for 30 days.After a sudden rise of the n... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Timeline-May Delcy Rodríguez reported the first cases of COVID-19 in Amazonas and Carabobo on 10 May. That left Delta Amacuro as the only unaffected state at that moment.Nicolás Maduro, on 12 May, extended the lockdown for 30 more days. The restrictions to national flights were also exten... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Timeline-June The easing of the lockdown started on 1 June, with gyms and shopping centers opening. Schools, courts and bars remain closed.As of 9 June the Venezuelan government had reduced re-emigrations to 400 per day, three days a week, a reduction of 80% from previous levels.The state... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Timeline-July Diosdado Cabello, vice-president of the United Socialist Party of Venezuela and president of the pro-government Constituent National Assembly announced he tested positive for COVID-19 on 9 July.Tareck El Aissami, the Minister of Petroleum and Omar Prieto, the Governor of Zul... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Timeline-August Venezuela Minister of Communication and Information Jorge Rodríguez tested positive for COVID-19 on 13 August. On the same day, Darío Vivas died of COVID-19 at the age of 70.
Timeline of 2021 February In February 2021, Venezuela started vaccinating health care workers with... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Measures-Executive response On 12 March, Nicolás Maduro declared a public health emergency in the country and suspended all inbound flights from Europe and Colombia for 30 days. He also announced that public gatherings were to be suspended and that the government would be evaluating wheth... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Measures-Russian Sputnik V vaccine In September 2020, Maduro suggested administering the Russian Sputnik V COVID-19 vaccine to the candidates in the upcoming legislative elections so that they could campaign safely. In October 2020, the Venezuelan government received a shipment of the Spu... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Measures-Doctors without Borders The international aid group Doctors without Borders (MSF) stopped operations in Caracas in November 2020 due to government restrictions. About 150 doctors, that worked in Petare, a poor neighborhood, risk to lose their jobs. Maribelsi Mancera, head nurse f... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Measures-National Assembly response In March 2020, Juan Guaidó said that the country is experiencing one of the most serious health crises in its history, caused by the inaction of the Maduro government, and announced a series of measures in order to take "responsible measures against the... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Measures-Joint response In June 2020, Carlos Alvarado, Maduro's health minister and Julio Castro, representing Juan Guaidó and the National Assembly, signed an unprecedent joint agreement with the World Health Organization and the Pan American Health Organization. The accord seeks coopera... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Measures-Other responses Baltazar Porras, Apostolic Administrator of Caracas, announced the suspension of ecclesiastic activities on 15 March, while assuring that temples would remain open, asking Venezuelans to avoid crowded places and to remain calm.The Health Ministry certified the mic... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Reactions-Government reactions Maduro asked people to not politicize the pandemic, while also expressing concern as to how the country could control the pandemic with the United States-imposed sanctions. Maduro called on US President Donald Trump to lift the sanctions so the country could... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Reactions-Other reactions The Venezuelan Medical Federation expressed condemnation at how a medic in Zulia was forced to leave for Colombia after denouncing the inability of Venezuela to cope if the disease arrived; it also asked for the release of the political prisoners in the country, ... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Reactions-International sanctions The Virtual United States Embassy in Venezuela rejected claims from Nicolás Maduro and Jorge Arreaza that sanctions are preventing the government from purchasing medical supplies, saying that "medicines, medical supplies, spare parts and components for me... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Reactions-International concern International concern was raised before the first cases were reported, as Venezuela's health care system has completely collapsed due to the ongoing crisis, meaning its already suffering population is especially vulnerable to the spread of a pandemic.Per th... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Reactions-Prison system Reuters reported that Venezuela's notoriously overcrowded and unsanitary prisons could spread the coronavirus "like a fast-moving fire." Venezuelan prisons frequently lack bathrooms, people sleep on floors, and many inmates spend their days without shirts or shoes ... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Reactions-Hearing over the Esequibo The International Court of Justice (ICJ) planned to discuss Guyana and Venezuela border dispute over Guayana Esequiba in March 2020. The hearing was postponed due to the pandemic. In April, Guyana reported cases of COVID-19 in the disputed territory.The... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Economic impact-As a result of the pandemic's economic impact, some businesses have sought to supplement lost business with deliveries, though exact figures remain obscure and the services are prohibitively costly for average Venezuelans. Some have started to make deliveries to support th... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Misinformation by authorities-In a national broadcast on 27 February 2020, Nicolás Maduro warned that COVID-19 may have been a US-made biological weapon aimed against China, without providing any evidence.Maduro has supported in social media the use of infusions as a cure to COVID-19. Twi... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Concerns with government estimates-The official reports have not always been consistent, presenting errors such as missing states, numbers that do not match and inconsistencies with the published estimates. The government keeps a centralized system and does not authorize private clinics a... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Authorities' actions on reporting-On 13 March, Delta Amacuro indigenous leader and journalist Melquiades Ávila, who has criticized health infrastructure in the country, questioned publicly through Facebook "will our hospital be ready for coronavirus?" and ridiculed Maduro's claim that 46 ... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Authorities' actions on reporting-Arrest of Darvinson Rojas On the night of 21 March 2020, journalist Darvinson Rojas was arrested at his home in Caracas by officials of the Bolivarian National Police (PNB) and around fifteen armed personnel from the Special Actions Force (FAES). Accordin... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Authorities' actions on reporting-Backlash on Venezuelan scientific report Venezuela's Academy of Physical, Mathematical and Natural Science published an estimate of the future cases in Venezuela in May 2020. The report predicts that the number of infected in Venezuela could reach 4000 ca... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Statistics-Cumulative number of cases and recoveries Notes: There was no official report on 20 March 2020, Worldometer and the Center for Systems Science and Engineering (CSSE) of the Johns Hopkins University reported 65 cases, numbers coming from an article of El Nacional from undisclose... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Statistics-Daily new cases Cumulative number of deaths Daily deaths Regional distribution Cases per federal entity touched by the pandemic, as of 29 September 2021: Various Venezuelan newspapers have pointed out that there have been some inconsistencies with the government reports by fede... | milkshake721/2.1M-wiki-STEM |
COVID-19 pandemic in Venezuela-Statistics-Per origin As of 16 March, there were 33 confirmed cases in Venezuela. According to official estimates, among these, 28 came from Europe and 5 from Cúcuta, Colombia. Two of the cases consisted of foreign citizens, one of a diplomatic official, while the rest consisted of Venezu... | milkshake721/2.1M-wiki-STEM |
2CB-Ind-2CB-Ind-2CB-Ind is a conformationally-restricted derivative of the phenethylamine hallucinogen 2C-B, discovered in 1974 by Alexander Shulgin. It acts as a moderately potent and selective agonist for the 5-HT2A and 5-HT2C receptors, but unlike the corresponding benzocyclobutene derivative TCB-2 which is consider... | milkshake721/2.1M-wiki-STEM |
Glycoside hydrolase family 66-Glycoside hydrolase family 66-In molecular biology, glycoside hydrolase family 66 is a family of glycoside hydrolases. | milkshake721/2.1M-wiki-STEM |
Glycoside hydrolase family 66-Glycoside hydrolase family 66-Glycoside hydrolases EC 3.2.1. are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycoside hydrolases, based on sequence ... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Periodontal abscess-A periodontal abscess (also termed lateral abscess, or parietal abscess), is a localized collection of pus (i.e. an abscess) within the tissues of the periodontium. It is a type of dental abscess. A periodontal abscess occurs alongside a tooth, and is different from the more comm... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Signs and symptoms-The main symptom is pain, which often suddenly appears, and is made worse by biting on the involved tooth, which may feel raised and prominent in the bite. The tooth may be mobile, and the lesion may contribute to destruction of the periodontal ligament and alveolar bone. The pain... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Signs and symptoms-When pus forms, the pressure increases, with increasing pain, until it spontaneously drains and relieves the pain. When pus drains into the mouth, a bad taste and smell are perceived. Usually drainage occurs via the periodontal pocket, or else the infection may spread as a celluli... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Causes-A periodontal abscess most commonly occurs as a complication of advanced periodontal disease (which is normally painless). A periodontal pocket contains dental plaque, bacteria and subgingival calculus. Periodontal pathogens continually find their way into the soft tissues, but normally they ... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Causes-Communication with the oral environment is maintained via the opening of the periodontal pocket. However, if the opening of a periodontal pocket becomes obstructed, as may occur if the pocket has become very deep (e.g. with furcation involvement), then plaque and calculus are trapped inside. ... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Causes-Penetrating injury to the gingiva--for example, with a toothbrush bristle, fishbone, toothpick or periodontal instrument--may inoculate bacteria into the tissues. Trauma to the tissues, such as serious impact on a tooth or excessive pressure exerted on teeth during orthodontic treatment, can ... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Causes-Systemic immune factors such as diabetes can predispose a person to the formation of periodontal abscesses.
Perforation of a root canal during endodontic therapy can also lead to a periodontal abscess which if left untreated could become "prolonged" ultimately rupture then enter the blood str... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Diagnosis-Periodontal abscesses may be difficult to distinguish from periapical abscesses. Since the management of a periodontal abscess is different from a periapical abscess, this differentiation is important to make (see Dental abscess#Diagnostic approach) For example, root canal therapy is unnec... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Treatment-An important factor is whether the involved tooth is to be extracted or retained. Although the pulp is usually still vital, a history of recurrent periodontal abscesses and significantly compromised periodontal support indicate that the prognosis for the tooth is poor and it should be remo... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Treatment-The initial management of a periodontal abscess involves pain relief and control of the infection. The pus needs to be drained, which helps both of these aims. If the tooth is to be removed, drainage will occur via the socket. Otherwise, if pus is already discharging from the periodontal p... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Treatment-Antibiotics are of secondary importance to drainage, which if satisfactory renders antibiotics unnecessary. Antibiotics are generally reserved for severe infections, in which there is facial swelling, systemic upset and elevated temperature. Since periodontal abscesses frequently involve a... | milkshake721/2.1M-wiki-STEM |
Periodontal abscess-Treatment-Other measures that are taken during management of the acute phase might include reducing the height of the tooth with a dental drill, so it no longer contacts the opposing tooth when biting down; and regular use of hot salt water mouth washes (antiseptic) that encourages further drainage ... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Single-machine scheduling-Single-machine scheduling or single-resource scheduling is an optimization problem in computer science and operations research. We are given n jobs J1, J2, ..., Jn of varying processing times, which need to be scheduled on a single machine, in a way that optimizes a c... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Single-machine scheduling-Single-machine scheduling is a special case of identical-machines scheduling, which is itself a special case of optimal job scheduling. Many problems, which are NP-hard in general, can be solved in polynomial time in the single-machine case.: 10–20 In the standard thr... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Single-machine scheduling-The makespan-minimization problem 1|| max , which is a common objective with multiple machines, is trivial with a single machine, since the makespan is always identical. Therefore, other objectives have been studied. | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Minimizing the sum of completion times-The problem 1|| ∑Cj aims to minimize the sum of completion times. It can be solved optimally by the Shortest Processing Time First rule (SPT): the jobs are scheduled by ascending order of their processing time pj The problem 1|| ∑wjCj aims to minimize th... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Minimizing the cost of lateness-The problem 1|| max aims to minimize the maximum lateness. For each job j, there is a due date dj . If it is completed after its due date, it suffers lateness defined as := Cj−dj . 1|| max can be solved optimally by the Earliest Due Date First rule (EDD): the ... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Maximizing the profit of earliness-In settings with deadlines, it is possible that, if the job is completed by the deadline, there is a profit pj. Otherwise, there is no profit. The goal is to maximize the profit. Single-machine scheduling with deadlines is NP-hard; Sahni presents both exact e... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Maximizing the throughput-The problem 1|| ∑Uj aims to minimize the number of late jobs, regardless of the amount of lateness. It can be solved optimally by the Hodgson-Moore algorithm.: lecture 3, part 1 It can also be interpreted as maximizing the number of jobs that complete on time; this n... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Maximizing the throughput-The problem 1|| ∑wjUj aims to minimize the weight of late jobs. It is NP-hard, since the special case in which all jobs have the same deadline (denoted by 1| dj=d |∑wjUj ) is equivalent to the Knapsack problem.: lecture 3, part 2 The problem 1| rj |∑Uj generalizes 1|... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Maximizing the throughput-The decision variant - deciding whether it is possible that all given jobs complete on time - can be solved by several algorithms, the fastest of them runs in time log n) .Jobs can have execution intervals. For each job j, there is a processing time tj and a start-t... | milkshake721/2.1M-wiki-STEM |
Single-machine scheduling-Maximizing the throughput-More generally, jobs can have time-windows, with both start-times and deadlines, which may be larger than the job length. Each job can be scheduled anywhere within its time-window. Bar-Noy, Bar-Yehuda, Freund, Naor and Schieber present a (1-ε)/2 approximation. | milkshake721/2.1M-wiki-STEM |
Cloroqualone-Cloroqualone-Cloroqualone is a quinazolinone-class GABAergic and is an analogue of methaqualone developed in the 1980s and marketed mainly in France and some other European countries. It has sedative and antitussive properties resulting from its agonist activity at the β subtype of the GABAa receptor and s... | milkshake721/2.1M-wiki-STEM |
Pedagogical relation-Pedagogical relation-The pedagogical relation refers to special kind of personal relationship between adult and child or adult or student for the sake of the child or student. The pedagogical relation is described by Hermann Nohl, Klaus Mollenhauer, and others in the Northern European human science... | milkshake721/2.1M-wiki-STEM |
Pedagogical relation-Pedagogical relation-In the pedagogical relation, adult and child encounter each other in ways that are different from other relationships (e.g., friendship) In the pedagogical relation the adult is directed toward the child. The relation is asymmetrical.. The adult is "there" for the child in a wa... | milkshake721/2.1M-wiki-STEM |
Pedagogical relation-Pedagogical relation-In the pedagogical relation the adult wants or intends both what is good for the child in the present and in the future. This relationship is oriented to what the child or young person may become (without trying to predetermine it), but without ignoring what is important for th... | milkshake721/2.1M-wiki-STEM |
Pedagogical relation-Pedagogical relation-The pedagogical relation comes to an end. The child grows up and the asymmetry of the relation dissolves. As Klaus Mollenhauer explains, "upbringing comes to an end when the child no longer needs to be "called" to self-activity, but instead has the wherewithal to educate himsel... | milkshake721/2.1M-wiki-STEM |
Pedagogical relation-Pedagogical relation-In the pedagogical relation, the adult mediates the relationship of the child with the world. This can happen by protecting the child from certain aspects of the world; it often happens by simplifying certain aspects of the world for the child, by directing the child's attentio... | milkshake721/2.1M-wiki-STEM |
Ro20-8552-Ro20-8552-Ro20-8552 is a benzodiazepine derivative with sedative and anxiolytic effects, which has been sold as a designer drug. | milkshake721/2.1M-wiki-STEM |
Polar amplification-Polar amplification-Polar amplification is the phenomenon that any change in the net radiation balance (for example greenhouse intensification) tends to produce a larger change in temperature near the poles than in the planetary average. This is commonly referred to as the ratio of polar warming to ... | milkshake721/2.1M-wiki-STEM |
Polar amplification-Polar amplification-Arctic amplification is polar amplification of the Earth's North Pole only; Antarctic amplification is that of the South Pole. | milkshake721/2.1M-wiki-STEM |
Polar amplification-History-An observation-based study related to Arctic amplification was published in 1969 by Mikhail Budyko, and the study conclusion has been summarized as "Sea ice loss affects Arctic temperatures through the surface albedo feedback." The same year, a similar model was published by William D. Selle... | milkshake721/2.1M-wiki-STEM |
Polar amplification-Amplification-Amplifying mechanisms Feedbacks associated with sea ice and snow cover are widely cited as one of the principal causes of terrestrial polar amplification. These feedbacks are particularly noted in local polar amplification, although recent work has shown that the lapse rate feedback is... | milkshake721/2.1M-wiki-STEM |
Polar amplification-Amplification-Ocean circulation It has been estimated that 70% of global wind energy is transferred to the ocean and takes place within the Antarctic Circumpolar Current (ACC). Eventually, upwelling due to wind-stress transports cold Antarctic waters through the Atlantic surface current, while warmi... | milkshake721/2.1M-wiki-STEM |
Polar amplification-Amplification-Amplification factor Polar amplification is quantified in terms of a polar amplification factor, generally defined as the ratio of some change in a polar temperature to a corresponding change in a broader average temperature: PAF=ΔTpΔT¯ ,where ΔTp is a change in polar temperature and ... | milkshake721/2.1M-wiki-STEM |
Polar amplification-Paleoclimate polar amplification-The glacial / interglacial cycles of the Pleistocene provide extensive palaeoclimate evidence of polar amplification, both from the Arctic and the Antarctic. In particular, the temperature rise since the last glacial maximum 20,000 years ago provides a clear picture.... | milkshake721/2.1M-wiki-STEM |
Polar amplification-Recent Arctic amplification-Suggested mechanisms leading to the observed Arctic amplification include Arctic sea ice decline (open water reflects less sunlight than sea ice), atmospheric heat transport from the equator to the Arctic, and the lapse rate feedback.The Arctic was historically described ... | milkshake721/2.1M-wiki-STEM |
Chi distribution-Chi distribution-In probability theory and statistics, the chi distribution is a continuous probability distribution over the non-negative real line. It is the distribution of the positive square root of a sum of squared independent Gaussian random variables. Equivalently, it is the distribution of the... | milkshake721/2.1M-wiki-STEM |
Chi distribution-Chi distribution-If Z1,…,Zk are k independent, normally distributed random variables with mean 0 and standard deviation 1, then the statistic Y=∑i=1kZi2 is distributed according to the chi distribution. The chi distribution has one positive integer parameter k , which specifies the degrees of freedo... | milkshake721/2.1M-wiki-STEM |
Chi distribution-Definitions-Probability density function The probability density function (pdf) of the chi-distribution is otherwise .
where Γ(z) is the gamma function.
Cumulative distribution function The cumulative distribution function is given by: F(x;k)=P(k/2,x2/2) where P(k,x) is the regularized gamma function... | milkshake721/2.1M-wiki-STEM |
Chi distribution-Properties-Moments The raw moments are then given by: μj=∫0∞f(x;k)xjdx=2j/2Γ(12(k+j))Γ(12k) where Γ(z) is the gamma function. Thus the first few raw moments are: μ1=2Γ(12(k+1))Γ(12k) μ2=k, μ3=22Γ(12(k+3))Γ(12k)=(k+1)μ1, μ4=(k)(k+2), μ5=42Γ(12(k+5))Γ(12k)=(k+1)(k+3)μ1, μ6=(k)(k+2)(k+4), where the right... | milkshake721/2.1M-wiki-STEM |
Chi distribution-Related distributions-If X∼χk then X2∼χk2 (chi-squared distribution) lim k→∞χk−μkσk→dN(0,1) (Normal distribution) If X∼N(0,1) then |X|∼χ1 If X∼χ1 then σX∼HN(σ) (half-normal distribution) for any σ>0 χ2∼Rayleigh(1) (Rayleigh distribution) χ3∼Maxwell(1) (Maxwell distribution) ‖Ni=1,…,k(0,1)‖2∼χk ,... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Lattice model (finance)-In finance, a lattice model is a technique applied to the valuation of derivatives, where a discrete time model is required. For equity options, a typical example would be pricing an American option, where a decision as to option exercise is required at "all" times (any t... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Equity and commodity derivatives-In general the approach is to divide time between now and the option's expiration into N discrete periods. At the specific time n, the model has a finite number of outcomes at time n + 1 such that every possible change in the state of the world between n and n + ... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Equity and commodity derivatives-As stated above, the lattice approach is particularly useful in valuing American options, where the choice whether to exercise the option early, or to hold the option, may be modeled at each discrete time/price combination; this is also true for Bermudan options.... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Equity and commodity derivatives-) The simplest lattice model is the binomial options pricing model; the standard ("canonical") method is that proposed by Cox, Ross and Rubinstein (CRR) in 1979; see diagram for formulae. Over 20 other methods have been developed, with each "derived under a varie... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Equity and commodity derivatives-As for the binomial, a similar (although smaller) range of methods exist. The trinomial model is considered to produce more accurate results than the binomial model when fewer time steps are modelled, and is therefore used when computational speed or resources ma... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Equity and commodity derivatives-Various of the Greeks can be estimated directly on the lattice, where the sensitivities are calculated using finite differences. Delta and gamma, being sensitivities of option value w.r.t. price, are approximated given differences between option prices - with the... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Equity and commodity derivatives-When it is important to incorporate the volatility smile, or surface, implied trees can be constructed. Here, the tree is solved such that it successfully reproduces selected (all) market prices, across various strikes and expirations. These trees thus "ensure th... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Equity and commodity derivatives-As an alternative, Edgeworth binomial trees allow for an analyst-specified skew and kurtosis in spot price returns; see Edgeworth series. This approach is useful when the underlying's behavior departs (markedly) from normality. A related use is to calibrate the t... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Equity and commodity derivatives-For multiple underlyers, multinomial lattices can be built, although the number of nodes increases exponentially with the number of underlyers. As an alternative, Basket options, for example, can be priced using an "approximating distribution" via an Edgeworth (o... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Interest rate derivatives-Lattices are commonly used in valuing bond options, Swaptions, and other interest rate derivatives In these cases the valuation is largely as above, but requires an additional, zeroeth, step of constructing an interest rate tree, on which the price of the underlying is ... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Interest rate derivatives-The initial lattice is built by discretizing either a short-rate model, such as Hull–White or Black Derman Toy, or a forward rate-based model, such as the LIBOR market model or HJM. As for equity, trinomial trees may also be employed for these models; this is usually th... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Interest rate derivatives-Under HJM, the condition of no arbitrage implies that there exists a martingale probability measure, as well as a corresponding restriction on the "drift coefficients" of the forward rates. These, in turn, are functions of the volatility(s) of the forward rates. A "simp... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Interest rate derivatives-In the latter case, the calibration is directly on the lattice: the fit is to both the current term structure of interest rates (i.e. the yield curve), and the corresponding volatility structure.
Here, calibration means that the interest-rate-tree reproduces the prices ... | milkshake721/2.1M-wiki-STEM |
Lattice model (finance)-Interest rate derivatives-The volatility structure—i.e. vertical node-spacing—here reflects the volatility of rates during the quarter, or other period, corresponding to the lattice time-step. (Some analysts use "realized volatility", i.e. of the rates applicable historically for the time-step; ... | milkshake721/2.1M-wiki-STEM |
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