Summary

HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Biography
Norman Rasmussen
Norman C. Rasmussen (November 12, 1927 – July 18, 2003) was an American physicist.[1] Rasmussen was born in Harrisburg, Pennsylvania. He grew up on a dairy farm as the fifth of six brothers. He attended public school in Hershey, Pennsylvania. His father died when he was in eighth grade, and his family moved to Gettysburg, where his grandparents helped to care for the family. Rasmussen gradu
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  • 22 Nov 2022
Topic Review
Lunar Orbital Platform-Gateway
The Lunar Orbital Platform-Gateway (LOP-G) is a planned lunar-orbit space station that will serve as an all-in-one solar-powered communications hub, science laboratory, short-term habitation module, and holding area for rovers and other robots. The science disciplines to be studied on the Gateway are expected to include planetary science, astrophysics, Earth observations, heliophysics, fundamental space biology and human health and performance. The Gateway is designed to be developed, serviced, and utilized in collaboration with commercial and international partners. It will also serve as the staging point for crewed and robotic lunar exploration and a staging point for NASA's proposed Deep Space Transport craft to perform a 300-400 day shakedown mission prior to NASA's first crewed Mars mission. Deep Space Transport is a concept of a reusable vehicle that uses electric and chemical propulsion and would be specifically designed for crewed missions to destinations such as Mars. The development is led by the International Space Station partners: ESA, NASA, Roscosmos, JAXA and CSA for construction in the 2020s. The International Space Exploration Coordination Group (ISECG), which comprises 14 space agencies participating with NASA, have concluded that LOP-G will be critical in expanding human presence to the Moon, Mars and deeper into the solar system. Formerly known as the Deep Space Gateway, the station was renamed in NASA's proposal for the 2019 United States federal budget. The omnibus spending bill passed by Congress in March of 2018 provided NASA with $504 million for the development of LOP-G in fiscal year 2019.
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  • 22 Nov 2022
Topic Review
Philistinism
In the fields of philosophy and æsthetics, the derogatory term philistinism describes “the manners, habits, and character, or mode of thinking of a philistine”, manifested as an anti-intellectual social attitude that undervalues and despises art and beauty, intellect and spirituality. A philistine person is a man or woman of smugly narrow mind and of conventional morality whose materialistic views and tastes indicate a lack of and an indifference to cultural and æsthetic values. Since the 19th century, the contemporary denotation of philistinism, as the behaviour of "ignorant, ill-behaved persons lacking in culture or artistic appreciation, and only concerned with materialistic values" derives from Matthew Arnold's adaptation to English of the German word Philister, as applied by university students in their antagonistic relations with the townspeople of Jena, Germany, where, in 1689, a row resulted in several deaths. In the aftermath, the university cleric addressed the town-vs-gown matter with an admonishing sermon "The Philistines Be Upon Thee", drawn from the Book of Judges (Chapt. 16, 'Samson vs the Philistines'), of the Tanakh and of the Christian Old Testament. In Word Research and Word History, the philologist Friedrich Kluge said that the word philistine originally had a positive meaning that identified a tall and strong man, such as Goliath; later the meaning changed to identify the "guards of the city".
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  • 22 Nov 2022
Topic Review
Xiaomi Smart Home
Xiaomi Smart Home Products (also known as Mi Ecosystem products) are products released by third-party manufacturers who have partnered with Xiaomi. These products are managed by Mi Home app.
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Topic Review
Propellant Depot
An orbital propellant depot is a cache of propellant that is placed in orbit around Earth or another body to allow spacecraft or the transfer stage of the spacecraft to be fueled in space. It is one of the types of space resource depots that have been proposed for enabling infrastructure-based space exploration. Many different depot concepts exist depending on the type of fuel to be supplied, location, or type of depot which may also include a propellant tanker that delivers a single load to a spacecraft at a specified orbital location and then departs. In-space fuel depots are not necessarily located near or at a space station. Potential users of in-orbit refueling and storage facilities include space agencies, defense ministries and communications satellite or other commercial companies. Satellite servicing depots would extend the lifetime of satellites that have nearly consumed all of their orbital maneuvering fuel and are likely placed in a geosynchronous orbit. The spacecraft would conduct a space rendezvous with the depot, or vice versa, and then transfer propellant to be used for subsequent orbital maneuvers. In 2011, Intelsat showed interest in an initial demonstration mission to refuel several satellites in geosynchronous orbit, but all plans have been since scrapped. A low earth orbit (LEO) depot's primary function would be to provide propellant to a transfer stage headed to the moon, Mars, or possibly a geosynchronous orbit. Since all or a fraction of the transfer stage propellant can be off-loaded, the separately launched spacecraft with payload and/or crew could have a larger mass or use a smaller launch vehicle. With a LEO depot or tanker fill, the size of the launch vehicle can be reduced and the flight rate increased—or, with a newer mission architecture where the beyond-Earth-orbit spacecraft also serves as the second stage, can facilitate much larger payloads—which may reduce the total launch costs since the fixed costs are spread over more flights and fixed costs are usually lower with smaller launch vehicles. A depot could also be placed at Earth-Moon Lagrange point 1 (EML-1) or behind the Moon at EML-2 to reduce costs to travel to the moon or Mars. Placing a depot in Mars orbit has also been suggested.
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  • 22 Nov 2022
Topic Review
Neuromodulation
Neuromodulation is "the alteration of nerve activity through targeted delivery of a stimulus, such as electrical stimulation or chemical agents, to specific neurological sites in the body". It is carried out to normalize – or modulate – nervous tissue function. Neuromodulation is an evolving therapy that can involve a range of electromagnetic stimuli such as a magnetic field (rTMS), an electric current, or a drug instilled directly in the subdural space (intrathecal drug delivery). Emerging applications involve targeted introduction of genes or gene regulators and light (optogenetics), and by 2014, these had been at minimum demonstrated in mammalian models, or first-in-human data had been acquired. The most clinical experience has been with electrical stimulation. Neuromodulation, whether electrical or magnetic, employs the body's natural biological response by stimulating nerve cell activity that can influence populations of nerves by releasing transmitters, such as dopamine, or other chemical messengers such as the peptide Substance P, that can modulate the excitability and firing patterns of neural circuits. There may also be more direct electrophysiological effects on neural membranes as the mechanism of action of electrical interaction with neural elements. The end effect is a "normalization" of a neural network function from its perturbed state. Presumed mechanisms of action for neurostimulation include depolarizing blockade, stochastic normalization of neural firing, axonal blockade, reduction of neural firing keratosis, and suppression of neural network oscillations. Although the exact mechanisms of neurostimulation are not known, the empirical effectiveness has led to considerable application clinically. Existing and emerging neuromodulation treatments also include application in medication-resistant epilepsy, chronic head pain conditions, and functional therapy ranging from bladder and bowel or respiratory control to improvement of sensory deficits, such as hearing (cochlear implants and auditory brainstem implants) and vision (retinal implants). Technical improvements include a trend toward minimally invasive (or noninvasive) systems; as well as smaller, more sophisticated devices that may have automated feedback control, and conditional compatibility with magnetic resonance imaging. Neuromodulation therapy has been investigated for other chronic conditions, such as Alzheimer's disease, depression, chronic pain, and as an adjunctive treatment in recovery from stroke.
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Topic Review
Biomarker
In medicine, a biomarker is a measurable indicator of the severity or presence of some disease state. More generally a biomarker is anything that can be used as an indicator of a particular disease state or some other physiological state of an organism. According to the WHO, the indicator may be chemical, physical, or biological in nature - and the measurement may be functional, physiological, biochemical, cellular, or molecular. A biomarker can be a substance that is introduced into an organism as a means to examine organ function or other aspects of health. For example, rubidium chloride is used in isotopic labeling to evaluate perfusion of heart muscle. It can also be a substance whose detection indicates a particular disease state, for example, the presence of an antibody may indicate an infection. More specifically, a biomarker indicates a change in expression or state of a protein that correlates with the risk or progression of a disease, or with the susceptibility of the disease to a given treatment. Biomarkers can be characteristic biological properties or molecules that can be detected and measured in parts of the body like the blood or tissue. They may indicate either normal or diseased processes in the body. Biomarkers can be specific cells, molecules, or genes, gene products, enzymes, or hormones. Complex organ functions or general characteristic changes in biological structures can also serve as biomarkers. Although the term biomarker is relatively new, biomarkers have been used in pre-clinical research and clinical diagnosis for a considerable time. For example, body temperature is a well-known biomarker for fever. Blood pressure is used to determine the risk of stroke. It is also widely known that cholesterol values are a biomarker and risk indicator for coronary and vascular disease, and that C-reactive protein (CRP) is a marker for inflammation. Biomarkers are useful in a number of ways, including measuring the progress of disease, evaluating the most effective therapeutic regimes for a particular cancer type, and establishing long-term susceptibility to cancer or its recurrence. The parameter can be chemical, physical or biological. In molecular terms biomarker is "the subset of markers that might be discovered using genomics, proteomics technologies or imaging technologies. Biomarkers play major roles in medicinal biology. Biomarkers help in early diagnosis, disease prevention, drug target identification, drug response etc. Several biomarkers have been identified for many diseases such as serum LDL for cholesterol, blood pressure, and P53 gene and MMPs as tumor markers for cancer.
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Topic Review
SAS
SAS (previously "Statistical Analysis System") is a statistical software suite developed by SAS Institute for data management, advanced analytics, multivariate analysis, business intelligence, criminal investigation, and predictive analytics. SAS was developed at North Carolina State University from 1966 until 1976, when SAS Institute was incorporated. SAS was further developed in the 1980s and 1990s with the addition of new statistical procedures, additional components and the introduction of JMP. A point-and-click interface was added in version 9 in 2004. A social media analytics product was added in 2010.
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  • 22 Nov 2022
Topic Review
Effects of Pornography on Relationships
Many individuals perceive pornography to have a negative effect on interpersonal relationships, satisfaction, and sexual functioning; however, findings on the topic are mixed. Pornography has never been so widely and universally accessible as it is today. As such, the consumption of pornography is on the rise, for both men and women. This unlimited access changes not only how individuals consume pornography, but how pornography can affect individuals and relationships. Pornography can impact many aspects of an individual’s life, and it is important to understand just what these effects are, as well as the extent to which these effects can reach.
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  • 22 Nov 2022
Topic Review
Indoor Air Pollution in Developing Nations
Indoor air pollution in developing nations is a significant form of indoor air pollution (IAP) that is little known to those in the developed world. Three billion people in developing countries across the globe rely on biomass, in the form of wood, charcoal, dung, and crop residue, as their domestic cooking fuel. Since much of the cooking is carried out indoors in environments that lack proper ventilation, millions of people, primarily poor women and children face serious health risks. The major sources of indoor air pollution include combustion and building materials. Globally, 4.3 million deaths were attributed to exposure to IAP in developing countries in 2012, almost all in low and middle-income countries. The South East Asian and Western Pacific regions bear most of the burden with 1.69 and 1.62 million deaths, respectively. Almost 600,000 deaths occur in Africa, 200,000 in the Eastern Mediterranean region, 99,000 in Europe and 81,000 in the Americas. The remaining 19,000 deaths occur in high-income countries. Even though the rate of dependence on biomass fuel is declining, this dwindling resource will not keep up with population growth which could ultimately put environments at even greater risk. Over the past several decades, there have been numerous studies investigating the air pollution generated by traditional household solid fuel combustion for space heating, lighting, and cooking in developing countries. It is now well established that, throughout much of the developing world, indoor burning of solid fuels (biomass, coal, etc.) by inefficient, often insufficiently vented, combustion devices results in elevated exposure to household air pollutants. This is due to the poor combustion efficiency of the combustion devices and the elevated nature of the emissions. In addition, they are often released directly into living areas. Smoke from traditional household solid fuel combustion commonly contains a range of incomplete combustion products, including both fine and coarse particulate matter (e.g., PM2.5, PM10), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and a variety of organic air pollutants (e.g., formaldehyde, 1,3-butadiene, benzene, acetaldehyde, acrolein, phenols, pyrene, benzopyrene, benzo(a)pyrene, dibenzopyrenes, dibenzocarbazoles, and cresols). In a typical solid fuel stove, about 6–20% of the solid fuel is converted into toxic emissions (by mass). The exact quantity and relative composition is determined by factors such as the fuel type and moisture content, stove type and operation influencing the amount. While many pollutants can evolve, most measurements have been focused on breathing-zone exposure levels of particulate matter (PM) and carbon monoxide (CO), which are the main products of incomplete combustion and are considered to pose the greatest health risks. Indoor PM2.5 exposure levels have been consistently reported to be in the range of hundreds to thousands of micrograms per cubic meter (μg/m3). Similarly, CO exposure levels have been measured to be as high as hundreds to greater than 1000 milligrams per cubic meter (mg/m3). A recent study of 163 households in two rural Chinese counties reported geometric mean indoor PM2.5 concentrations of 276 μg/m3 (combinations of different plant materials, including wood, tobacco stems, and corncobs), 327 μg/m3 (wood), 144 μg/m3 (smoky coal), and 96 μg/m3 (smokeless coal) for homes using a variety of different fuel types and stove configurations (e.g., vented, unvented, portable, fire pit, mixed ventilation stove).
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