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Topic Review
Plant Stinging Hairs
True stinging hairs are highly specialized plant structures that are able to inject a physiologically active liquid into the skin. They can be classified into two basic types: Urtica-type stinging hairs with the classical “hypodermic syringe” mechanism expelling only liquid, and Tragia-type stinging hairs expelling a liquid together with a sharp crystal. Since the middle of the 20th century, neurotransmitters(acetylcholine, histamine, serotonin) have been repeatedly detected in stinging hairs of Urticaceae; these substances can explain some of the physiological effects of stinging hairs, but fail to completely explain neuropathic effects, pointing to some yet unidentified neurotoxins. 
  • 4.3K
  • 22 Sep 2021
Topic Review
Juan Manuel de Rosas
Template:Infobox governor Juan Manuel de Rosas (30 March 1793 – 14 March 1877), nicknamed "Restorer of the Laws", was a politician and army officer who ruled Buenos Aires Province and briefly the Argentine Confederation. Although born into a wealthy family, Rosas independently amassed a personal fortune, acquiring large tracts of land in the process. Rosas enlisted his workers in a private militia, as was common for rural proprietors, and took part in the disputes that led to numerous civil wars in his country. Victorious in warfare, personally influential, and with vast landholdings and a loyal private army, Rosas became a caudillo, as provincial warlords in the region were known. He eventually reached the rank of brigadier general, the highest in the Argentine Army, and became the undisputed leader of the Federalist Party. In December 1829, Rosas became governor of the province of Buenos Aires and established a dictatorship backed by state terrorism. In 1831, he signed the Federal Pact, recognising provincial autonomy and creating the Argentine Confederation. When his term of office ended in 1832, Rosas departed to the frontier to wage war on the indigenous peoples. After his supporters launched a coup in Buenos Aires, Rosas was asked to return and once again took office as governor. Rosas reestablished his dictatorship and formed the repressive Mazorca, an armed parapolice that killed thousands of citizens. Elections became a farce, and the legislature and judiciary became docile instruments of his will. Rosas created a cult of personality and his regime became totalitarian in nature, with all aspects of society rigidly controlled. Rosas faced many threats to his power during the late 1830s and early 1840s. He fought a war against the Peru–Bolivian Confederation, endured a blockade by France, faced a revolt in his own province and battled a major rebellion that lasted for years and spread to several Argentine provinces. Rosas persevered and extended his influence in the provinces, exercising effective control over them through direct and indirect means. By 1848, he had extended his power beyond the borders of Buenos Aires and was ruler of all of Argentina. Rosas also attempted to annex the neighbouring nations of Uruguay and Paraguay. France and Great Britain jointly retaliated against Argentine expansionism, blockading Buenos Aires for most of the late 1840s, but were unable to halt Rosas, whose prestige was greatly enhanced by his string of successes. When the Empire of Brazil began aiding Uruguay in its struggle against Argentina, Rosas declared war in August 1851, starting the Platine War. This short conflict ended with Rosas being defeated and absconding to Britain. His last years were spent in exile living as a tenant farmer until his death in 1877. Rosas garnered an enduring public perception among Argentines as a brutal tyrant. Since the 1930s, an authoritarian, anti-Semitic, and racist political movement in Argentina called Revisionism has tried to improve Rosas's reputation and establish a new dictatorship in the model of his regime. In 1989, his remains were repatriated by the government in an attempt to promote national unity, seeking forgiveness for him and especially for the 1970s military dictatorship. Rosas remains a controversial figure in Argentina in the 21st century.
  • 4.3K
  • 13 Oct 2022
Topic Review
Battery Modelling Techniques
The battery modelling (BM) problem is a constrained, multi-dimensional, mixed variable, non-convex, non-linear optimisation problem. Many bio-inspired techniques have been successfully employed to estimate the battery parameters. When bio-inspired algorithms are implemented for COM to extract parameters in real time, then they are called grey box models.
  • 4.3K
  • 28 Oct 2021
Topic Review
Copper-Based Conductive Inks
Silver (Ag), gold (Au), and copper (Cu) have been utilized as metals for fabricating metal-based inks/pastes for printed/flexible electronics. Among them, Cu is the most promising candidate for metal-based inks/pastes. Cu has high intrinsic electrical/thermal conductivity, which is more cost-effective and abundant, as compared to Ag. Moreover, the migration tendency of Cu is less than that of Ag. Thus, recently, Cu-based inks/pastes have gained increasing attention as conductive inks/pastes for printed/flexible electronics. We can divide Cu-based inks/pastes into four categories from the viewpoints of Cu sources: (i) traditional micron-sized flake/powder type, (ii) nanoparticle type, (iii) nanowire type, and (iv) precursor ion type. However, the disadvantages of Cu-based inks/pastes are their instability against oxidation under an ambient condition and tendency to form insulating layers of Cu oxide, such as cuprous oxide (Cu2O) and cupric oxide (CuO). The formation of the Cu oxidation causes a low conductivity in sintered Cu films and interferes with the sintering of Cu particles. The surface and interface designs for Cu-based conductive inks/pastes are important strategies for the oxidation resistance of Cu and low-temperature sintering to produce highly conductive Cu patterns/electrodes on flexible substrates. The surface control approaches include surface designs by polymers, small ligands, core-shell structures, and surface activation. The Cu-based mixed inks/pastes offer improved performances compared with the single use of each component.
  • 4.3K
  • 07 Sep 2020
Topic Review
Antenna
Antennae (Template:Singular antenna), sometimes referred to as "feelers", are paired appendages used for sensing in arthropods. Antennae are connected to the first one or two segments of the arthropod head. They vary widely in form but are always made of one or more jointed segments. While they are typically sensory organs, the exact nature of what they sense and how they sense it is not the same in all groups. Functions may variously include sensing touch, air motion, heat, vibration (sound), and especially smell or taste. Antennae are sometimes modified for other purposes, such as mating, brooding, swimming, and even anchoring the arthropod to a substrate. Larval arthropods have antennae that differ from those of the adult. Many crustaceans, for example, have free-swimming larvae that use their antennae for swimming. Antennae can also locate other group members if the insect lives in a group, like the ant. The common ancestor of all arthropods likely had one pair of uniramous (unbranched) antenna-like structures, followed by one or more pairs of biramous (having two major branches) leg-like structures, as seen in some modern crustaceans and fossil trilobites. Except for the chelicerates and proturans, which have none, all non-crustacean arthropods have a single pair of antennae.
  • 4.3K
  • 25 Oct 2022
Topic Review
Universe & Anharmonic Oscillator & Singularity Avoidance Higgs
The functioning of our universe and atomic is based on the oscillation of the particle itself and asymmetrically between matter and antimatter. This mechanism is a classical an-harmonic oscillator and uses a linear oscillation of the particle, where the energy can be represented by the graph of a potential well. In this potential well the alternation of energies ocurs between the kinetic energy and potential energy. This an-harmonic oscillation of the particle thus occurs through a gravitational oscillator (see "hole through the Earth simple harmonic motion"), followed by a singularity avoidance. Indeed the important kinetics of the particle leads to a singularity avoidance to pass over the supermassive black hole to plot the Higgs field/potential. The alternation of the particle at very high frequency generates by the principle of mass-energy equivalence in vacuum (E=mc²) a mass flux expressed by the quantum fluctuation determined by a scalar energy density. This scalar density represents for example the dark matter and the residues of the latter in the quantum vacuum. However a vectorial interpretation of the particle is possible as soon as its oscillation through the oscillator is really minimized before becoming a mass-energy equivalence flux. That represent the elements related to Einstein's Stress Energy Tensor. Here is the one of interpretation of quantum mechanics in relation to relativistic physics. 
  • 4.3K
  • 23 Aug 2022
Topic Review
Chemical Depolymerization Methods of Poly(ethylene terephthalate)
The significant amount of waste generated by poly(ethylene terephthalate) (PET) requires the development of a recycling process chain in which chemical recycling plays an important role. On the one hand, it allows the depolymerization of degraded plastics that do not meet the quality requirements to be used in mechanical recycling, and on the other hand, provides an opportunity to process cheap waste and obtain products with greater added value. It can be widely used in the recycling of both packaging plastics and textiles, or other waste generated with PET.
  • 4.3K
  • 12 Oct 2023
Topic Review
Beam Steering Characteristics of Reconfigurable Transmitarray Antennas
The high gain beam steering antennas are widely used in 5G wireless mobile communications, radio frequency (RF) wireless power transmission, and satellite communications. In order to obtain high gain and beam steering characteristics, traditionally, antennas of the same type as phased array antennas, reflectarray antennas, and parabolic antennas have been designed. The transmitarray (TA) has attracted more and more interest from researchers due to its low profile, affordable cost, lower losses, low design complexity, and ease of fabrication. These have become popular solutions due to their remarkable applications, for instance, in biomedical systems (Brain and Breast Cancer Detection), civil and military radar systems, imaging systems, satellite communications, direct broadcasting services, and 6G/5G communication systems, etc.
  • 4.3K
  • 03 Mar 2022
Topic Review
Solar Power
Solar power is the conversion of renewable energy from sunlight into electricity, either directly using photovoltaics (PV), indirectly using concentrated solar power, or a combination. Photovoltaic cells convert light into an electric current using the photovoltaic effect. Concentrated solar power systems use lenses or mirrors and solar tracking systems to focus a large area of sunlight to a hot spot, often to drive a steam turbine. Photovoltaics were initially solely used as a source of electricity for small and medium-sized applications, from the calculator powered by a single solar cell to remote homes powered by an off-grid rooftop PV system. Commercial concentrated solar power plants were first developed in the 1980s. Since then, as the cost of solar electricity has fallen, grid-connected solar PV systems have grown more or less exponentially. Millions of installations and gigawatt-scale photovoltaic power stations have been and are being built. Solar PV has rapidly become a viable low-carbon technology, and as of 2020, provides the cheapest source of electricity in history. As of 2021, solar generates 4% of the world's electricity, compared to 1% in 2015 when the Paris Agreement to limit climate change was signed. Along with onshore wind, the cheapest levelised cost of electricity is utility-scale solar. The International Energy Agency said in 2021 that under its "Net Zero by 2050" scenario solar power would contribute about 20% of worldwide energy consumption, and solar would be the world's largest source of electricity.
  • 4.3K
  • 20 Oct 2022
Topic Review
Nutritional Values of Dabai (Canarium odontophyllum)
Dabai (Canarium odontophyllum) is a fruit-bearing plant native to Borneo. Its fruit is an indigenous seasonal fruit that is considered to be underutilized due to its short shelf life.
  • 4.3K
  • 25 Nov 2022
Topic Review
Platinum Group Minerals
Russia and South Africa are the world’s leading producers of platinum group elements (PGEs). This places them in a unique position regarding the supply of these two key industrial commodities. The purpose of this paper is to provide a comparative high-level overview of aspects of the geological occurrence, mineralogy, and processing by flotation of the platinum group minerals (PGMs) found in each country. A summary of some of the major challenges faced in each country in terms of the concentration of the ores by flotation is presented alongside the opportunities that exist to increase the production of the respective metals. These include the more efficient recovery of minerals such as arsenides and tellurides, the management of siliceous gangue and chromite in the processing of these ores, and, especially in Russia, the development of novel processing routes to recover PGEs from relatively low grade ores occurring in dunites, black shale ores and in vanadium-iron-titanium-sulphide oxide formations.
  • 4.3K
  • 26 Jan 2021
Topic Review
Structure from Motion
Structure from Motion (SfM) is a photogrammetric range imaging technique for estimating three-dimensional structures from two-dimensional image sequences that may be coupled with local motion signals. It is studied in the fields of computer vision and visual perception. In biological vision, SfM refers to the phenomenon by which humans (and other living creatures) can recover 3D structure from the projected 2D (retinal) motion field of a moving object or scene.
  • 4.3K
  • 06 Oct 2022
Topic Review
Tourism-phobia
The perception of residents of tourist areas affected by intensification of tourism or overtourism, has changed from a positive or neutral vision to overt annoyance or irritation, which has generated a certain debate that has been conveyed in the media, an innovative aspect in the field of tourism. The term tourism phobia is mentioned for the first time in Spain linked to problems related to tourism and tourists. Donaire (Romero et al., 2019) specifically mentions the term tourism-phobia, referring to discontent in the latter stages in the Doxey's model (1975). Huete and Mantecón (2018) and Milano (2017, 2018) have linked tourism-phobia with a certain social opposition and criticism of tourist management. Milano (2018) describes that social criticism within a context of social organizations and residents outlining their disagreement with certain tourist activities. Huete and Mantecón (2018) coincides with Milano by pointing out that what the  media considers to be tourism-phobia is essentially a social critique of certain aspects of tourism. Other authors (Alcalde et al., 2018) highlight that the concept of tourism- phobia has been used in a misguided way, confusing the social discontent due to too many tourists with the rejection of them. Simultaneously and as opposed to the concept of tourism-phobia, the term tourism-philia arises, which refers to the perception of the positive effects of tourism on the local economy and society (Zerva et al., 2019).
  • 4.3K
  • 27 Oct 2020
Topic Review
Low Molecular Weight Chitosan
Chitosan is a biopolymer with high added value, and its properties are related to its molecular weight. Thus, high molecular weight values provide low solubility of chitosan, presenting limitations in its use. Based on this, several studies have developed different hydrolysis methods to reduce the molecular weight of chitosan.
  • 4.3K
  • 13 Aug 2021
Topic Review
Ring Expansion and Ring Contraction
Ring expansion and ring contraction reactions in the course of organic synthesis refer to a set of reactions which can lead to the expansion or contraction of an existing ring. This often makes it possible to access structures that would be difficult if not impossible to synthesise with single cyclization reactions. Ring expansions are valuable because they allow access to larger systems that are difficult to synthesize through a single cyclization due to the slow rate of formation. Ring contractions are useful for making smaller, more strained rings from larger rings. Expansions are classified by the mechanism of expansion and the atom(s) added; contractions are characterized simply by the reactive intermediate which performs the contraction.
  • 4.3K
  • 01 Dec 2022
Topic Review
Skin Stem Cells and Wound Healing
The human skin is a necessary organ for survival; therefore, its integrity and uncompromised function are essential. Normally, skin wounds can heal without problem; however, some diseases or extensive damage may delay or prevent healing. Skin stem cells (SSCs) are heavily involved in the healing process, as they can replace, restore, and regenerate the epidermal cells that may have been lost, damaged, or have become pathologically dysfunctional. However, non-healing wounds represent a serious and life-threatening scenario that may require advanced therapeutic strategies that may involve the use of stem cell allografts.
  • 4.3K
  • 26 Oct 2021
Topic Review
Blockchain
This entry provides an overview of the application of blockchain technologies for enabling traceability in the agri-food domain. It presents relevant definitions and the various types of blockchain solutions used in "farm to fork" traceability, including public vs private blockchain networks, consensus protocols and smart contracts.
  • 4.3K
  • 10 Jul 2020
Topic Review
Gendered Citizenship, Inequality, and Well-Being in Qatar
The impact of gendered citizenship on the well-being of cross-national families following the political blockade imposed on Qatar in 2017. More specifically, it examines how these families, women, and children face challenges related to their lives, well-being, and rights. Twenty-three face-to-face interviews were conducted with Qatari and non-Qatari women and men married to non-Qatari spouses residing in Qatar. 
  • 4.3K
  • 15 Jun 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
  • 4.3K
  • 14 Nov 2022
Topic Review
Threats to Sustainability
Plastics are a precious, versatile set of materials. The accumulation of plastic waste threatens the environment. Recycling plastic waste can produce many new products. The many opportunities for using plastic waste create pressure for a strategy to develop or improve current waste management systems to reduce the negative impact on humans, fauna and flora.
  • 4.3K
  • 13 Dec 2022
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