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Topic Review

Chinese Polearms

The three most common types of Chinese polearms are the ge (戈), qiang (槍), and ji (戟). They are translated into English as dagger-axe, spear, and halberd. Dagger-axes were originally a short slashing weapon with a 0.9 to 1.8 m long shaft, but around the 4th century BC a spearhead was added to the blade, and it became a halberd. The spear is also sometimes called a mao (矛), which is sometimes used to designate polearms with a wavy snake-like spearhead. There was another polearm weapon known as the pi (鈹), translated into English as either sword-staff or long lance, that was used from ancient times until the Han dynasty. It was essentially a short sword attached to a stick. From the Warring States period onward, the length of Chinese polearms varied from around 2.8 m to 5.5 m, however there is no specific designation for a pike in the traditional Chinese lexicon. A very long spear is just called a long spear.

9.0K
13 Oct 2022

Topic Review

Seed Morphology

Seed morphology is the scientific analysis and description of the shape of seeds.

9.0K
28 Oct 2020

Topic Review

A lingua franca is any language widely used beyond the population of its native speakers. The de facto status of lingua franca is usually "awarded" by the masses to the language of the most influential nation(s) of the time. Any given language normally becomes a lingua franca primarily by being used for international commerce, but can be accepted in other cultural exchanges, especially diplomacy. Occasionally the term "lingua franca" is applied to a fully established formal language; thus formerly it was said that French was the lingua franca of diplomacy. The term "lingua franca" was originally used by Arabs to name all Romance languages, and especially Italian (Arabs used the name 'Franks' for all peoples in Western Europe). Then, it meant a language with a Romance lexicon (most words derived from Latin which then evolved into early forms of Spanish and Italian) and a very simple grammar, that till the end of the 19th century was used by mariners in the Mediterranean Sea, particularly in the Middle East and Northern Africa. A related concept is that of a “vehicular language.” It is defined as a basic linguistic structure for proposed “international auxiliary languages,” for example, the use of an Indo-European language, or Indo-European itself, in the development of Esperanto.

9.0K
20 Oct 2022

Topic Review

Zipline (Drone Delivery)

Zipline is an American medical product delivery company that is headquartered in South San Francisco, California, and which designs, manufactures, and operates delivery drones. The company operates distribution centers in Rwanda, Ghana, and the US, with signed agreements to begin service in Japan , Nigeria, Cote d'Ivoire, and Kenya. As of December 2021, its drones have made over 225,000 commercial deliveries. The company's drones deliver whole blood, platelets, frozen plasma, and cryoprecipitate along with medical products including vaccines, infusions and routine medical commodities. As of September 2021, more than 75% of blood deliveries in Rwanda outside of Kigali use Zipline drones. In April 2019 in Ghana, the company began using drones to deliver vaccines, blood, and medicines. During the COVID-19 pandemic in 2020, the US Federal Aviation Administration (FAA) granted a Part 107 waiver to Zipline's partner organization Novant Health for the delivery of medical supplies and personal protective equipment (PPE) to medical facilities in North Carolina. Along with nine other drone delivery companies, the FAA selected Zipline to participate in a type certification program for delivery drones.

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06 Oct 2022

Topic Review

Nature has two inter-related meanings in philosophy and natural philosophy. On the one hand, it means the set of all things which are natural, or subject to the normal working of the laws of nature. On the other hand, it means the essential properties and causes of individual things. How to understand the meaning and significance of nature has been a consistent theme of discussion within the history of Western Civilization, in the philosophical fields of metaphysics and epistemology, as well as in theology and science. The study of natural things and the regular laws which seem to govern them, as opposed to discussion about what it means to be natural, is the area of natural science. The word "nature" derives from Latin nātūra, a philosophical term derived from the verb for birth, which was used as a translation for the earlier (pre-Socratic) Greek term phusis, derived from the verb for natural growth. Already in classical times, philosophical use of these words combined two related meanings which have in common that they refer to the way in which things happen by themselves, "naturally", without "interference" from human deliberation, divine intervention, or anything outside what is considered normal for the natural things being considered. Understandings of nature depend on the subject and age of the work where they appear. For example, Aristotle's explanation of natural properties differs from what is meant by natural properties in modern philosophical and scientific works, which can also differ from other scientific and conventional usage. Stoicism encourages practitioners to live in accordance with nature. Pyrrhonism encourages practitioners to use the guidance of nature in decision making.

9.0K
09 Oct 2022

Topic Review

Deep Eutectic Solvents (DES)

Deep eutectic solvent (DES) are a highly non-ideal mixture of two biodegradable components (HBA and HBD) associated with strong hydrogen bonding interactions.

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08 Mar 2022

Topic Review

Luminiferous Aether

Luminiferous aether or ether ("luminiferous", meaning "light-bearing") was the postulated medium for the propagation of light. It was invoked to explain the ability of the apparently wave-based light to propagate through empty space, something that waves should not be able to do. The assumption of a spatial plenum of luminiferous aether, rather than a spatial vacuum, provided the theoretical medium that was required by wave theories of light. The aether hypothesis was the topic of considerable debate throughout its history, as it required the existence of an invisible and infinite material with no interaction with physical objects. As the nature of light was explored, especially in the 19th century, the physical qualities required of an aether became increasingly contradictory. By the late 1800s, the existence of the aether was being questioned, although there was no physical theory to replace it. The negative outcome of the Michelson–Morley experiment (1887) suggested that the aether did not exist, a finding that was confirmed in subsequent experiments through the 1920s. This led to considerable theoretical work to explain the propagation of light without an aether. A major breakthrough was the theory of relativity, which could explain why the experiment failed to see aether, but was more broadly interpreted to suggest that it was not needed. The Michelson-Morley experiment, along with the blackbody radiator and photoelectric effect, was a key experiment in the development of modern physics, which includes both relativity and quantum theory, the latter of which explains the particle-like nature of light.

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17 Oct 2022

Topic Review

Acer Aspire Laptops

Acer Aspire (stylized as Λspire or ΛSPIRE) is a series of personal computers by Acer Inc. aimed at the casual household user or for small business use. The Aspire series covers both desktop computers and laptops. Acer developed the series in order to cover from essentials to high performances. Many of the Aspire laptops, such as model 8920G, have built in Blu-ray drives, 5.1 audio outputs and transflective displays. Acer was the first to include these drives in laptops. Most Aspire laptops have water-resistant screens, such as the 1410 and the 5741 Z. In 2007, Acer introduced the Gemstone series that marked a milestone in the Acer Aspire line. As with many Windows laptops, different models may have different specification in different parts of the world.

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20 Oct 2022

Topic Review

Acid throwing, also called an acid attack, a vitriol attack or vitriolage, is a form of violent assault defined as the act of throwing acid or a similarly corrosive substance onto the body of another "with the intention to disfigure, maim, torture, or kill". Perpetrators of these attacks throw corrosive liquids at their victims, usually at their faces, burning them, and damaging skin tissue, often exposing and sometimes dissolving the bones. The most common types of acid used in these attacks are sulfuric and nitric acid. Hydrochloric acid is sometimes used, but is much less damaging. Aqueous solutions of strongly alkaline materials, such as caustic soda (sodium hydroxide), are used as well, particularly in areas where strong acids are controlled substances. The long term consequences of these attacks may include blindness, as well as permanent scarring of the face and body, along with far-reaching social, psychological, and economic difficulties. Today, acid attacks are reported in many parts of the world. Since the 1990s, Bangladesh has been reporting the highest number of attacks and highest incidence rates for women, with 3,512 Bangladeshi people acid attacked between 1999 and 2013, and in Pakistan and India acid attacks are at an all-time high and increasing every year. Although acid attacks occur all over the world, this type of violence is most common in South Asia. The UK has one of the highest rates of acid attacks per capita in the world, according to Acid Survivors Trust International (ASTI). In 2016 there were over 601 acid attacks in the UK based on ASTI figures. Over 1,200 cases were recorded over the past 5 years. From 2011 to 2016 there were 1,464 crimes involving acid or corrosive substance in London alone.

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21 Oct 2022

Topic Review

History, Preparation, Characterization and Applications of Moisturizers

Moisturizers are one of the most widely used preparations in cosmetics and have been extensively used to soften the skin for consumers. Cosmetically, moisturizers make the skin smooth by the mechanism of increasing the water content in the stratum corneum, hence exerting its most vital action, which is moisturizing action and maintaining a normal skin pH.

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13 Jul 2022

Topic Review

The Effect of Parental Styles on Social Skills

Parental educational styles have a significant effect in personal development. These styles (authoritative, democratic, permissive and neglectful) can be related to affects and social skills at the individual level. The results suggest that parenting styles are closely related to affects and social skills. It is also suggested that affects play a mediating role in the relationship between parenting styles and social skills.

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23 Mar 2022

Topic Review

Remarriage is a marriage that takes place after a previous marital union has ended, as through divorce or widowhood. Some individuals are more likely to remarry than others; the likelihood can differ based on previous relationship status (e.g. divorced vs. widowed), level of interest in establishing a new romantic relationship, gender, race, and age among other factors. Those who choose not to remarry may prefer alternative arrangements like cohabitation or living apart together. Remarriage also provides mental and physical health benefits. However, although remarried individuals tend to have better health than individuals who do not repartner, they still generally have worse health than individuals who have remained continuously married. Someone who repeatedly remarries is referred to as a serial wedder.

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27 Oct 2022

Topic Review

Applications of Heterocyclic Compounds

Fluorescently labelled heterocyclic compounds are useful in bioanalytical applications, including in vivo imaging, high throughput screening, diagnostics, and light-emitting diodes. These compounds have various therapeutic properties, including antifungal, antitumor, antimalarial, anti-inflammatory, and analgesic activities. Different neutral fluorescent markers containing nitrogen heterocycles (quinolones, azafluoranthenes, pyrazoloquinolines, etc.) have several electrochemical, biological, and nonlinear optic applications. Photodynamic therapy (PDT), which destroys tumors and keeps normal tissues safe, works in the presence of molecular oxygen with light and a photosensitizing drugs (dye) to obtain a therapeutic effect.

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18 Oct 2022

Topic Review

Atomic units (au or a.u.) form a system of natural units which is especially convenient for atomic physics calculations. There are two different kinds of atomic units, Hartree atomic units and Rydberg atomic units, which differ in the choice of the unit of mass and charge. This article deals with Hartree atomic units, where the numerical values of the following four fundamental physical constants are all unity by definition: In Hartree units, the speed of light is approximately [math]\displaystyle{ 137 }[/math]. Atomic units are often abbreviated "a.u." or "au", not to be confused with the same abbreviation used also for astronomical units, arbitrary units, and absorbance units in different contexts.

9.0K
10 Nov 2022

Topic Review

The KH-11 KENNEN (later renamed CRYSTAL, then Evolved Enhanced CRYSTAL System, and codenamed 1010 and Key Hole) is a type of reconnaissance satellite first launched by the American National Reconnaissance Office in December 1976. Manufactured by Lockheed in Sunnyvale, California, the KH-11 was the first American spy satellite to use electro-optical digital imaging, and so offer real-time optical observations. Later KH-11 satellites have been referred to by outside observers as KH-11B or KH-12, and by the names "Advanced KENNEN", "Improved Crystal" and "Ikon". Official budget documents refer to the latest generation of electro-optical satellites as Evolved Enhanced CRYSTAL System. The Key Hole series was officially discontinued in favor of a random numbering scheme after repeated public references to KH-7 Gambit, KH-8 Gambit-3, KH-9 Hexagon, and KH-11 satellites. The capabilities of the KH-11 are highly classified, as are images they produce. The satellites are believed to have been the source of some imagery of the Soviet Union and China made public in 1997; images of Sudan and Afghanistan made public in 1998 related to the response to the 1998 U.S. embassy bombings; and a 2019 photo, revealed by President Donald Trump, of a failed Iranian rocket launch.

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09 Oct 2022

Topic Review

Multijet is Fiat Chrysler Automobiles' term for its current common rail direct injection turbodiesel engine range. Most of the Fiat, Alfa Romeo, Lancia range as well as certain Chrysler, RAM Trucks, Jeep and Maserati vehicles are equipped with Multijet engines. Ownership of some Fiat Multijet designs is shared with General Motors as part of a settlement of the failed merger between the two auto conglomerates. GM Powertrain Torino group in Turin, Italy manages their interest in these engines. Some PSA Peugeot Citroën diesel engines are also rebadged JTD units, and vice versa. Fiat's common rail diesel engine is also known as JTD, an initialism of Jet Turbo Diesel.

8.9K
13 Oct 2022

Biography

Deepak Chopra (/ˈdiːpɑːk ˈtʃoʊprə/; Hindi: [d̪iːpək tʃoːpraː]; born October 22, 1946) is an Indian-born American author and alternative-medicine advocate.[1][2] A prominent figure in the New Age movement,[3] his books and videos have made him one of the best-known and wealthiest figures in alternative medicine.[4] Chopra studied medicine in India before emigrating in 1970 to the

8.9K
05 Dec 2022

Topic Review

Micronutrient Deficiency and Toxicity in Plants

Micronutrients are essential for plants. Their growth, productivity and reproduction are directly influenced by the supply of micronutrients. Currently, there are eight trace elements considered to be essential for higher plants: Fe, Zn, Mn, Cu, Ni, B, Mo, and Cl. Possibly, other essential elements could be discovered because of recent advances in nutrient solution culture techniques and in the commercial availability of highly sensitive analytical instrumentation for elemental analysis.

8.9K
27 Sep 2022

Topic Review Peer Reviewed

Challenges for Nanotechnology

The term “Nanotechnology” describes a large field of scientific and technical activities dealing with objects and technical components with small dimensions. Typically, bodies that are in–at least–two dimensions smaller than 0.1 µm are regarded as “nanobjects”. By this definition, a lot of advanced materials, as well as the advanced electronic devices, are objects of nanotechnology. In addition, many aspects of molecular biotechnology as well as macromolecular and supermolecular chemistry and nanoparticle techniques are summarized under “nanotechnology”. Despite this size-oriented definition, nanotechnology is dealing with physics and chemistry as well as with the realization of technical functions in the area between very small bodies and single particles and molecules. This includes the shift from classical physics into the quantum world of small molecules and low numbers or single elementary particles. Besides the already established fields of nanotechnology, there is a big expectation about technical progress and solution to essential economic, medical, and ecological problems by means of nanotechnology. Nanotechnology can only meet these expectations if fundamental progress behind the recent state of the art can be achieved. Therefore, very important challenges for nanotechnology are discussed here.

8.9K
13 Apr 2022

Topic Review

Trickle-Down Economics

Trickle-down economics, also called trickle-down theory, refers to the economic proposition that taxes on businesses and the wealthy in society should be reduced as a means to stimulate business investment in the short term and benefit society at large in the long term. In recent history, the term has been used by critics of supply-side economic policies, such as "Reaganomics". Whereas general supply-side theory favors lowering taxes overall, trickle-down theory more specifically targets taxes on the upper end of the economic spectrum. The term "trickle-down" originated as a joke by humorist Will Rogers and today is often used to criticize economic policies that favor the wealthy or privileged while being framed as good for the average citizen. David Stockman, who as Ronald Reagan's budget director championed Reagan's tax cuts at first, later became critical of them and told journalist William Greider that "supply-side economics" is the trickle-down idea: Political opponents of the Reagan administration soon seized on this language in an effort to brand the administration as caring only about the wealthy. Some studies suggest a link between trickle-down economics and reduced growth. Trickle-down economics has been widely criticized, particularly by left-wing, centre-left and moderate politicians and economists, but also some right-wing politicians. A 2019 study in the Journal of Political Economy found, contrary to trickle-down theory, that "the positive relationship between tax cuts and employment growth is largely driven by tax cuts for lower-income groups and that the effect of tax cuts for the top 10 percent on employment growth is small."

8.9K
02 Dec 2022

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