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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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MRNA Vaccine
An mRNA vaccine is a type of vaccine that uses a copy of a molecule called messenger RNA (mRNA) to produce an immune response. The vaccine delivers molecules of antigen-encoding mRNA into immune cells, which use the designed mRNA as a blueprint to build foreign protein that would normally be produced by a pathogen (such as a virus) or by a cancer cell. These protein molecules stimulate an adaptive immune response that teaches the body to identify and destroy the corresponding pathogen or cancer cells. The mRNA is delivered by a co-formulation of the RNA encapsulated in lipid nanoparticles that protect the RNA strands and help their absorption into the cells. File:MRNA vaccines against the coronavirus.webm Reactogenicity, the tendency of a vaccine to produce adverse reactions, is similar to that of conventional non-RNA vaccines. People susceptible to an autoimmune response may have an adverse reaction to messenger RNA vaccines. The advantages of mRNA vaccines over traditional vaccines are ease of design, speed and lower cost of production, the induction of both cellular and humoral immunity, and lack of interaction with the genomic DNA. While some messenger RNA vaccines, such as the Pfizer–BioNTech COVID-19 vaccine, have the disadvantage of requiring ultracold storage before distribution, other mRNA vaccines, such as the Moderna, CureVac, and Walvax COVID-19 vaccines, do not have such requirements. In RNA therapeutics, messenger RNA vaccines have attracted considerable interest as COVID-19 vaccines. In December 2020, Pfizer–BioNTech and Moderna obtained authorization for their mRNA-based COVID-19 vaccines. On 2 December, the UK Medicines and Healthcare products Regulatory Agency (MHRA) became the first medicines regulator to approve an mRNA vaccine, authorizing the Pfizer–BioNTech vaccine for widespread use. On 11 December, the US Food and Drug Administration (FDA) issued an emergency use authorization for the Pfizer–BioNTech vaccine and a week later similarly authorized the Moderna vaccine.
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  • 16 Nov 2022
Topic Review
Gauss' Method
In orbital mechanics (subfield of celestial mechanics), Gauss's method is used for preliminary orbit determination from at least three observations (more observations increases the accuracy of the determined orbit) of the orbiting body of interest at three different times. The required information are the times of observations, the position vectors of the observation points (in Equatorial Coordinate System), the direction cosine vector of the orbiting body from the observation points (from Topocentric Equatorial Coordinate System) and general physical data. Carl Friedrich Gauss developed important mathematical techniques (summed up in Gauss's methods) which were specifically used to determine the orbit of Ceres. The method shown following is the orbit determination of an orbiting body about the focal body where the observations were taken from, whereas the method for determining Ceres' orbit requires a bit more effort because the observations were taken from Earth while Ceres orbits the Sun.
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  • 10 Nov 2022
Topic Review
Creation–Evolution Controversy
The creation–evolution controversy (also termed the creation vs. evolution debate or the origins debate) involves an ongoing, recurring cultural, political, and theological dispute about the origins of the Earth, of humanity, and of other life. Species were once widely believed to be fixed products of divine creation in accordance with creationism, but since the mid-19th century evolution by natural selection has been established as an empirical scientific fact. The debate is religious, not scientific: in the scientific community, evolution is accepted as fact and efforts to sustain the traditional view are almost universally regarded as pseudoscience. While the controversy has a long history, today it has retreated to be mainly over what constitutes good science education, with the politics of creationism primarily focusing on the teaching of creationism in public education. Among majority-Christian countries, the debate is most prominent in the United States, where it may be portrayed as part of a culture war. Parallel controversies also exist in some other religious communities, such as the more fundamentalist branches of Judaism and Islam. In Europe and elsewhere, creationism is less widespread (notably, the Catholic Church and Anglican Communion both accept evolution), and there is much less pressure to teach it as fact. Christian fundamentalists repudiate the evidence of common descent of humans and other animals as demonstrated in modern paleontology, genetics, histology and cladistics and those other sub-disciplines which are based upon the conclusions of modern evolutionary biology, geology, cosmology, and other related fields. They argue for the Abrahamic accounts of creation, and, in order to attempt to gain a place alongside evolutionary biology in the science classroom, have developed a rhetorical framework of "creation science". In the landmark Kitzmiller v. Dover, the purported basis of scientific creationism was exposed as a wholly religious construct without formal scientific merit. The Catholic Church now recognizes the existence of evolution (see Catholic Church and evolution). Pope Francis has stated: "God is not a demiurge or a magician, but the Creator who brought everything to life...Evolution in nature is not inconsistent with the notion of creation, because evolution requires the creation of beings that evolve." The rules of genetic evolutionary inheritance were first discovered by a Catholic priest, the Augustinian monk Gregor Mendel, who is known today as the founder of modern genetics. According to a 2014 Gallup survey, "More than four in 10 Americans continue to believe that God created humans in their present form 10,000 years ago, a view that has changed little over the past three decades. Half of Americans believe humans evolved, with the majority of these saying God guided the evolutionary process. However, the percentage who say God was not involved is rising." A 2015 Pew Research Center survey found "that while 37% of those older than 65 thought that God created humans in their present form within the last 10,000 years, only 21% of respondents between the ages of 18 and 29 agreed." The debate is sometimes portrayed as being between science and religion, and the United States National Academy of Sciences states:
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  • 10 Nov 2022
Topic Review
Deception Technology
Deception technology is a category of cyber security defense. Deception technology products can detect, analyze, and defend against zero-day and advanced attacks, often in real time. They are automated, accurate, and provide insight into malicious activity within internal networks which may be unseen by other types of cyber defense. Deception technology enables a more proactive security posture by seeking to deceive the attackers, detect them and then defeat them, allowing the enterprise to return to normal operations. Existing defense-in-depth cyber technologies have struggled against the increasing wave of sophisticated and persistent human attackers. These technologies seek primarily to defend a perimeter, but both firewalls and endpoint security cannot defend a perimeter with 100% certainty. Cyber-attackers can penetrate these networks and move unimpeded for months, stealing data and intellectual property. Heuristics may find an attacker within the network, but often generate so many alerts that critical alerts are missed. Since 2014, attacks have accelerated and there is evidence that cyber-attackers are penetrating traditional defenses at a rapidly increasing rate. Deception technology considers the human attacker's point of view and method for exploiting and navigating networks to identify and exfiltrate data. It integrates with existing technologies to provide new visibility into the internal networks, share high probability alerts and threat intelligence with the existing infrastructure.
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  • 10 Nov 2022
Topic Review
Geocoding
Geocoding is the process of taking input text, such as an address or the name of a place, and returning a latitude/longitude location on the Earth's surface for that place. Reverse geocoding, on the other hand, converts geographic coordinates to a description of a location, usually the name of a place or an addressable location. Geocoding relies on a computer representation of address points, the street / road network, together with postal and administrative boundaries. The geographic coordinates representing locations often vary greatly in positional accuracy. Examples include building centroids, land parcel centroids, interpolated locations based on thoroughfare ranges, street segments centroids, postal code centroids (e.g. ZIP codes, CEDEX), and Administrative division Centroids.
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  • 10 Nov 2022
Topic Review
Plug-In Electric Vehicles in the Netherlands
The adoption of plug-in electric vehicles in the Netherlands is actively supported by the Dutch government through the exemption of the registration fee and road taxes. These purchase incentives have been adjusted over time. Considering the potential of plug-in electric vehicles in the country due to its relative small size and geography, the Dutch government set a target of 15,000 to 20,000 electric vehicles with three or more wheels on the roads in 2015; 200,000 vehicles in 2020; and 1 million vehicles in 2025. The first two targets were achieved two years earlier than planned. The Dutch plug-in market was dominated by plug-in hybrids until 2016, when the tax rules changed after it became apparent many users rarely used the electric motors and only bought the cars for their tax advantage. In 2019, plug-in electric passenger cars had a market share of 14.9%, and rose to 24.6% in 2020, with battery electric vehicles dominating sales in both years. (As of December 2020), there were 297,380 highway-legal light-duty plug-in electric vehicles on the road in the Netherlands, consisting of 182,481 fully electric cars, 108,652 plug-in hybrids, and 6,247 all-electric light utility vans. (As of December 2012), the Netherlands was the country with the highest ratio of slow charging points to electric vehicles (EVSE/EV), with a ratio of more than 0.50, while the U.S had a slow EVSE/EV ratio of 0.20. The Netherlands' mix of slow and fast chargers has allowed it to become the country with the highest number of charging point per capita in the world. (As of December 2016), there were 11,768 public slow charging points available 24/7, 14,320 slow charging point with limited public access, 612 public and semi-public fast charging points, and over 72,000 private charging points.
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  • 10 Nov 2022
Biography
Arthur Berson
Arthur Josef Stanislaus Berson (6 August 1859 – 3 December 1942) was a German[1][2] meteorologist and pioneer of aerology who was a native of Neu Sandez, Galicia (now Nowy Sącz, Poland ). After visiting the gymnasium in Neu Sandez, Berson studied philology in Vienna. He then studied meteorology and geography in Berlin, where he had as instructors Ferdinand von Richthofen and Wilhelm von Bezo
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  • 14 Nov 2022
Topic Review
Arthropoda
Arthropods (/ˈɑːrθrəpɒd/, from grc ἄρθρον (arthron) 'joint', and πούς (pous) 'foot' (gen. ποδός)) are invertebrate animals having an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior organs; it has an open circulatory system. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is "ladder-like", with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fusion of the ganglia of these segments and encircle the esophagus. The respiratory and excretory systems of arthropods vary, depending as much on their environment as on the subphylum to which they belong. Arthropods use combinations of compound eyes and pigment-pit ocelli for vision. In most species, the ocelli can only detect the direction from which light is coming, and the compound eyes are the main source of information, but the main eyes of spiders are ocelli that can form images and, in a few cases, can swivel to track prey. Arthropods also have a wide range of chemical and mechanical sensors, mostly based on modifications of the many bristles known as setae that project through their cuticles. Similarly, their reproduction and development are varied; all terrestrial species use internal fertilization, but this is sometimes by indirect transfer of the sperm via an appendage or the ground, rather than by direct injection. Aquatic species use either internal or external fertilization. Almost all arthropods lay eggs, but many species give birth to live young after the eggs have hatched inside the mother, and a few are genuinely viviparous, such as aphids. Arthropod hatchlings vary from miniature adults to grubs and caterpillars that lack jointed limbs and eventually undergo a total metamorphosis to produce the adult form. The level of maternal care for hatchlings varies from nonexistent to the prolonged care provided by social insects. The evolutionary ancestry of arthropods dates back to the Cambrian period. The group is generally regarded as monophyletic, and many analyses support the placement of arthropods with cycloneuralians (or their constituent clades) in a superphylum Ecdysozoa. Overall, however, the basal relationships of animals are not yet well resolved. Likewise, the relationships between various arthropod groups are still actively debated. Today, Arthropods contribute to the human food supply both directly as food, and more importantly, indirectly as pollinators of crops. Some species are known to spread severe disease to humans, livestock, and crops.
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  • 10 Nov 2022
Biography
Frederick W. Lander
Frederick William[1][2] Lander (December 17, 1821 – March 2, 1862) was a transcontinental United States explorer, general in the Union Army during the American Civil War, and a prolific poet. Lander was born in Salem, Massachusetts, the son of Edward and Eliza West Lander; his sister was the sculptor Louisa Lander. He was educated at Governor Dummer Academy, Phillips Academy, Andover and No
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  • 10 Nov 2022
Biography
Thomas Gold
Thomas Gold (also known as Tommy Gold),[1] (May 22, 1920 – June 22, 2004[2]) was an Austrian-born astrophysicist, a professor of astronomy at Cornell University, a member of the U.S. National Academy of Sciences, and a Fellow of the Royal Society (London).[2] Gold was one of three young Cambridge scientists who in 1948 proposed the now mostly abandoned "steady state" hypothesis of the universe
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  • 14 Nov 2022
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