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Osmium-180
Osmium (76Os) has seven naturally occurring isotopes, five of which are stable: 187Os, 188Os, 189Os, 190Os, and (most abundant) 192Os. The other natural isotopes, 184Os, and 186Os, have extremely long half-life (1.12×1013 years and 2×1015 years, respectively) and for practical purposes can be considered to be stable as well. 187Os is the daughter of 187Re (half-life 4.56×1010 years) and is most often measured in an 187Os/188Os ratio. This ratio, as well as the 187Re/188Os ratio, have been used extensively in dating terrestrial as well as meteoric rocks. It has also been used to measure the intensity of continental weathering over geologic time and to fix minimum ages for stabilization of the mantle roots of continental cratons. However, the most notable application of Os in dating has been in conjunction with iridium, to analyze the layer of shocked quartz along the Cretaceous–Paleogene boundary that marks the extinction of the dinosaurs 66 million years ago. There are also 30 artificial radioisotopes, the longest-lived of which is 194Os with a half-life of six years; all others have half-lives under 94 days. There are also nine known nuclear isomers, the longest-lived of which is 191mOs with a half-life of 13.10 hours. All isotopes and nuclear isomers of osmium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.
  • 994
  • 01 Nov 2022
Topic Review
Ke'o Language
Kéo is an Austronesian language belonging to the Kéo ethnic group (‘ata Kéo, ‘Kéo people’) that reside in an area southeast of the Ebu Lobo volcano in the south-central part of Nusa Tenggara Timur Province on the island of Flores, eastern Indonesia. Kéo belongs to the Malayo-Polynesian, Central-Eastern Malayo-Polynesian, Bima-Lembata subgroups of the Austronesian language family and there are approximately 40,000 speakers. Kéo is sometimes referred to as Nage-Kéo, the Nage being the name of a neighbouring ethnic group that is generally considered culturally distinct from Kéo, however whether or not the two languages are separate entities is ambivalent. Uncommon to Austronesian languages, Kéo is a highly isolating language that lacks inflectional morphology or clear morphological derivation. Instead it relies more heavily on lexical and syntactic grammatical processes.
  • 838
  • 01 Nov 2022
Topic Review
Pharmacogenetics
Pharmacogenetics is the study of inherited genetic differences in drug metabolic pathways (and other pharmacological principles, like enzymes, messengers and receptors) which can affect individual responses to drugs, both in terms of therapeutic effect as well as adverse effects. The term pharmacogenetics is often used interchangeably with the term pharmacogenomics which also investigates the role of acquired and inherited genetic differences in relation to drug response and drug behaviour through a systematic examination of genes, gene products, and inter- and intra-individual variation in gene expression and function. In oncology, pharmacogenetics historically is the study of germline mutations (e.g., single-nucleotide polymorphisms affecting genes coding for liver enzymes responsible for drug deposition and pharmacokinetics), whereas pharmacogenomics refers to somatic mutations in tumoral DNA leading to alteration in drug response (e.g., KRAS mutations in patients treated with anti-Her1 biologics). Pharmacogenetics is believed to account for inter-ethnic differences (e.g., between patients of Asian, Caucasian and African descent) in adverse events and efficacy profiles of many widely used drugs in cancer chemotherapy.
  • 797
  • 01 Nov 2022
Topic Review
Medical Ethnobotany of India
The medical ethnobotany of India is the study of Indian medicinal plants and their traditional uses. Plants have been used in India for treatment of disease and health maintenance for thousands of years, and remain important staples of health and folk medicine for millions. Indians today utilize plants for both primary medical care (principally in Rural and undeserved areas) and as supplementary treatment alongside modern medical science. It is estimated that 70% of rural Indians use traditional plant based remedies for primary healthcare needs. This reliance of plants for medicine is consistent with trends widely observed in the developing world, where between 65% and 80% of people use medicinal plant remedies. Herbal medicine in India is largely guided by folk medicine, both in codified cultural practices shared widely (Ayurveda, Siddha, Unani), and highly localized practices unique to individual tribes or tribal groups (Adivasi). Between 3,000 and 5,000 species of medicinal plants grow in India with roughly 1,000 threatened with extinction. Of these, more than 2,400 plant species have been documented for medicinal use.
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  • 01 Nov 2022
Topic Review
List of Volcanic Eruptions on Iceland
This is a list of recorded volcanic eruptions on Iceland.
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  • 01 Nov 2022
Topic Review
Kaharingan
Kaharingan is a folk religion professed by many Dayaks in Kalimantan, Indonesia; particularly Central Kalimantan, although many have converted to Christianity or Islam. The word means life, and this belief system includes a concept of a supreme deity—although this may be the result of the need to conform to the idea of "One Supreme God" (Ketuhanan yang Maha Esa), which is the first principle of the Indonesian state ideology Pancasila. Hindu-Javanese influence can be seen in this religion, and the Indonesian government views it as a form of Hinduism because the Indonesian government recognizes only six official religions, and Kaharingan is not one of them. The main festival of Kaharingan is the Tiwah festival, which lasts for thirty days, and involves the sacrifice of many animals like buffaloes, cows, pigs and chickens, as offerings to the Supreme God. The supreme God in Kaharingan is called Ranying. In addition, the religion has ritual offerings called Yadnya, places of worship called Balai Basarah or Balai Kaharingan and a holy book called Panaturan, Talatah Basarah (group of prayers) and Tawar (a guide to seek God's help by giving rice).
  • 3.4K
  • 02 Nov 2022
Topic Review
Network Interface Controller
A network interface controller (NIC, also known as a network interface card, network adapter, LAN adapter or physical network interface, and by similar terms) is a computer hardware component that connects a computer to a computer network. Early network interface controllers were commonly implemented on expansion cards that plugged into a computer bus. The low cost and ubiquity of the Ethernet standard means that most newer computers have a network interface built into the motherboard, or is contained into a USB-connected dongle. Modern network interface controllers offer advanced features such as interrupt and DMA interfaces to the host processors, support for multiple receive and transmit queues, partitioning into multiple logical interfaces, and on-controller network traffic processing such as the TCP offload engine.
  • 2.5K
  • 02 Nov 2022
Topic Review
Zend Framework
Zend Framework (ZF) is an open source, object-oriented web application framework implemented in PHP 7 and licensed under the New BSD License. The framework is basically a collection of professional PHP-based packages. The framework uses various packages by the use of Composer as part of its package dependency managers; some of them are PHPUnit for testing all packages, Travis CI for continuous Integration Services. Zend Framework provides to users a support of the Model View Controller (MVC) in combination with Front Controller solution. MVC implementation in Zend Framework has five main areas. The router and dispatcher functions to decide which controller to run based on data from URL, and controller functions in combination with the model and view to develop and create the final web page. On 17 April 2019 it was announced that the framework is transitioning into an open source project hosted by the Linux Foundation to be known as Laminas.
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  • 01 Nov 2022
Topic Review
Hook-Up Culture
Hook-up culture refers to a culture built on the approved practice of engaging in hook-ups, or sexual encounters between two or more individuals where it is understood that commitment, relationships, and emotional feelings are not expected outcomes. Defining a hook-up is ambiguous because it can have a variety of meanings ranging from casual Kissing to foreplay and oral sex, or in some cases, it can mean participating in sexual intercourse. Hook-ups typically only last a short time and those involved are typically only interested in experiencing sexual intimacy and pleasure. Not all hook-ups can be classified as "one-night stands", however, since some people believe they can eventually lead to dating or more personal connections. While people have engaged in casual sex for many years, the act of "hooking-up" has become increasingly popular on college and university campuses in the United States over the last decade. Hooking up has become common for many college students, and the practice has replaced more traditional 20th century ideas about dating. Furthermore, social media sites like Facebook or Match, and phone applications like Grindr and Tinder have given users an opportunity to form connections with other people who have similar sexual interests or desires. Studying hook-up culture focuses on its influences on the formation and management of friendships and romantic relationships. The growth of hook-up culture is also shaping gender roles, specifically in regards to sexual behavior. Aside from these aspects of hook-ups, taking part in uncommitted sex can lead to potential negative physical and emotional impacts.
  • 22.6K
  • 02 Nov 2022
Topic Review
Chemtrail Conspiracy Theory
The chemtrail conspiracy theory posits the erroneous belief that long-lasting condensation trails are "chemtrails" consisting of chemical or biological agents left in the sky by high-flying aircraft, sprayed for nefarious purposes undisclosed to the general public. Believers in this conspiracy theory say that while normal contrails dissipate relatively quickly, contrails that linger must contain additional substances. Those who subscribe to the theory speculate that the purpose of the chemical release may be solar radiation management, weather modification, psychological manipulation, human population control, biological or chemical warfare, or testing of biological or chemical agents on a population, and that the trails are causing respiratory illnesses and other health problems. The claim has been dismissed by the scientific community. There is no evidence that purported chemtrails differ from normal water-based contrails routinely left by high-flying aircraft under certain atmospheric conditions. Although proponents have tried to prove that chemical spraying occurs, their analyses have been flawed or based on misconceptions. Because of the persistence of the conspiracy theory and questions about government involvement, scientists and government agencies around the world have repeatedly explained that the supposed chemtrails are in fact normal contrails. The term chemtrail is a portmanteau of the words chemical and trail, just as contrail is a portmanteau of condensation and trail.
  • 29.6K
  • 31 Oct 2022
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