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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
Ocean Planet
An ocean planet, ocean world, water world, aquaplanet or panthalassic planet is a type of terrestrial planet that contains a substantial amount of water either at its surface or subsurface. The term ocean world is also used sometimes for astronomical bodies with an ocean composed of a different fluid, such as lava (the case of Io), ammonia (in a eutectic mixture with water, as is likely the case of Titan's inner ocean) or hydrocarbons like on Titan's surface (which could be the most abundant kind of exosea). Earth is the only astronomical object known to have bodies of liquid water on its surface, although several exoplanets have been found with the right conditions to support liquid water. For exoplanets, current technology cannot directly observe liquid surface water, so atmospheric water vapor may be used as a proxy. The characteristics of ocean worlds—or ocean planets—provide clues to their history and the formation and evolution of the Solar System as a whole. Of additional interest is their potential to originate and host life.
  • 4.3K
  • 19 Oct 2022
Topic Review
Wild Food Plants
Wild food plants (WFPs) are generally considered species that grow spontaneously in self-sustaining populations outside cultivated areas, in field margins, forests, woodland, grassland, and wetlands (e.g., paddy fields), independently of human activity. However, the distinction between “wild” and “cultivated” or “domesticated” is not so clear-cut and many wild food plants fall somewhere in between these two extremes depending on the degree of human intervention and management. Semi-domesticated species, in addition to economically important non-timber forest food products, such as açaí berries and Brazil nuts, can also be considered "wild" to some extent as they grow naturally in forest with limited management or human intervention. As they are often wild relatives of domesticated species, WFPs have potential for domestication and can provide a pool of genetic resources for hybridization and selective breeding.
  • 4.3K
  • 13 May 2024
Topic Review
Noble Gases Magnetic Properties Explorations
In recent years, we have seen spectacular growth in the experimental and theoretical investigations of magnetic properties of small subatomic particles: electrons, positrons, muons, and neutrinos. However, conventional methods for establishing these properties for atomic nuclei are also in progress, due to new, more sophisticated theoretical achievements and experimental results performed using modern spectroscopic devices. In this review, a brief outline of the history of experiments with nuclear magnetic moments in magnetic fields of noble gases is provided. In particular, nuclear magnetic resonance (NMR) and atomic beam magnetic resonance (ABMR) measurements are included in this text. Various aspects of NMR methodology performed in the gas phase are discussed in detail. The basic achievements of this research are reviewed, and the main features of the methods for the noble gas isotopes: 3He, 21Ne, 83Kr, 129Xe, and 131Xe are clarified. A comprehensive description of short lived isotopes of argon (Ar) and radon (Rn) measurements is included. Remarks on the theoretical calculations and future experimental intentions of nuclear magnetic moments of noble gases are also provided.
  • 4.3K
  • 10 Dec 2020
Topic Review Peer Reviewed
Active Edible Packaging
Active edible packaging is a food packaging made of comestible bioproducts and active compounds that interacts with the food. The bioproducts, usually biopolymers, must be recognized as safe and with characteristics to be consumed by humans—comestible—and not toxic and capable of carrying an active compound, like anti-browning agents, colorants, flavors, nutrients, antimicrobial and/or antioxidant compounds, in order to extend the product shelf-life, reduce contamination and maintain or even enhance the nutritional value.
  • 4.3K
  • 13 Apr 2022
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.
  • 4.2K
  • 25 Oct 2022
Topic Review
Driving Mechanisms/Motion of Screw Drive
In recent years, interest in in-pipe robot research has been steadily increasing. This phenomenon reflects the necessity and urgency of pipe inspection and rehabilitation as several pipe networks have become outdated around the globe. In-pipe robots can be divided into several groups in accordance with their locomotion principles, each with its own advantages and best suited application scope. Research on the screw drive in-pipe robot (SDIR) has had a rising trend due to the robot’s simple driving mechanism design and numerous advantages. 
  • 4.2K
  • 09 Nov 2020
Topic Review
List of Cities by Sunshine Duration
The following is a list of cities by sunshine duration. Sunshine duration is a climatological indicator, measuring duration of sunshine in given period (usually, a day or a year) for a given location on Earth, typically expressed as an averaged value over several years. It is a general indicator of cloudiness of a location, and thus differs from insolation, which measures the total energy delivered by sunlight over a given period. Sunshine duration is usually expressed in hours per year, or in (average) hours per day. The first measure indicates the general sunniness of a location compared with other places, while the latter allows for comparison of sunshine in various seasons in the same location. Another often-used measure is percentage ratio of recorded bright sunshine duration and daylight duration in the observed period. An important use of sunshine duration data is to characterize the climate of sites, especially of health resorts. This also takes into account the psychological effect of strong solar light on human well-being. It is often used to promote tourist destinations.
  • 4.2K
  • 03 Nov 2022
Topic Review
Antimicrobial Peptides for Wound Infections
Antimicrobial peptides (AMPs), also called host defense peptides (HDPs), are found in bacteria, fungi, plants, and animals. They typically consist of 10–50 amino acid residues (very rarely up to 100 amino acids) and generally possess cationic (net charge ranging from −4 to +20) and amphipathic structures. 
  • 4.2K
  • 09 Dec 2020
Topic Review
Iron Complexation and Flavonoids
Flavonoids are common plant natural products able to suppress ROS-related damage and alleviate oxidative stress. One of key mechanisms, involved in this phenomenon is chelation of transition metal ions. From a physiological perspective, iron is the most significant transition metal, because of its abundance in living organisms and ubiquitous involvement in redox processes. The chemical, pharmaceutical, and biological properties of flavonoids can be significantly affected by their interaction with transition metal ions, mainly iron.
  • 4.2K
  • 26 Jan 2021
Biography
Qutb Al-Din Al-Shirazi
Qotb al-Din Mahmoud b. Zia al-Din Mas'ud b. Mosleh Shirazi (1236–1311) (Persian: قطب‌الدین محمود بن ضیاالدین مسعود بن مصلح شیرازی‎) was a 13th-century Persian[1] polymath and poet who made contributions to astronomy, mathematics, medicine, physics, music theory, philosophy and Sufism.[2][3] He was born in Kazerun in October 1236 to a family with a
  • 4.2K
  • 28 Nov 2022
Topic Review
Electric Organ
In biology, the electric organ is an organ common to all electric fish used for the purposes of creating an electric field. The electric organ is derived from modified nerve or muscle tissue. The electric discharge from this organ is used for navigation, communication, mating, defense and also sometimes for the incapacitation of prey.
  • 4.2K
  • 29 Sep 2022
Topic Review
Skin Lesion Datasets and Image Preprocessing
Skin lesions affect millions of people worldwide. They can be easily recognized based on their typically abnormal texture and color but are difficult to diagnose due to similar symptoms among certain types of lesions.
  • 4.2K
  • 18 Apr 2023
Topic Review
Mechanism of Photocatalytic Water Splitting
The constant increase in the amount of energy consumed and environmental problems associated with the use of fossil fuels determine the relevance of the search for alternative and renewable energy sources. One of the most promising renewable fuels is hydrogen gas, which can be produced by sunlight-driven photocatalytic water splitting. The decisive role in the efficiency of the process is played by the properties of the photocatalyst. Oxide materials are widely used as photocatalysts due to their appropriate band structure, high-enough photochemical stability and corrosion resistance. However, the bandgap, crystallinity and the surface morphology of oxide materials are subject to improvement. In order to choose an appropriate oxide semiconductor photocatalytic material and strategies of its modification it is necessary to examine the mechanism of the photocatalytic water splitting.
  • 4.2K
  • 01 Aug 2022
Topic Review
Scopes Trial
The Scopes Trial, formally known as The State of Tennessee v. John Thomas Scopes and commonly referred to as the Scopes Monkey Trial, was an American legal case in July 1925 in which a substitute high school teacher, John T. Scopes, was accused of violating Tennessee 's Butler Act, which had made it unlawful to teach human evolution in any state-funded school. The trial was deliberately staged in order to attract publicity to the small town of Dayton, Tennessee, where it was held. Scopes was unsure whether he had ever actually taught evolution, but he purposely incriminated himself so that the case could have a defendant. Scopes was found guilty and fined $100 (equivalent to $1458 in 2019), but the verdict was overturned on a technicality. The trial served its purpose of drawing intense national publicity, as national reporters flocked to Dayton to cover the big-name lawyers who had agreed to represent each side. William Jennings Bryan, three-time presidential candidate, argued for the prosecution, while Clarence Darrow, the famed defense attorney, spoke for Scopes. The trial publicized the Fundamentalist–Modernist Controversy, which set Modernists, who said evolution was not inconsistent with religion, against Fundamentalists, who said the word of God as revealed in the Bible took priority over all human knowledge. The case was thus seen as both a theological contest and a trial on whether "modern science" should be taught in schools.
  • 4.2K
  • 15 Nov 2022
Topic Review
Nrf2 and Oxidative Stress
Organisms are continually exposed to exogenous and endogenous sources of reactive oxygen species (ROS) and other oxidants that have both beneficial and deleterious effects on the cell. ROS have important roles in a wide range of physiological processes; however, high ROS levels are associated with oxidative stress and disease progression. Oxidative stress has been implicated in nearly all major human diseases, from neurogenerative diseases and neuropsychiatric disorders to cardiovascular disease, diabetes, and cancer. Antioxidant defence systems have evolved as a means of protection against oxidative stress, with the transcription factor Nrf2 as the key regulator.
  • 4.2K
  • 01 Feb 2023
Topic Review
Cotton Production in Pakistan
Cotton production in Pakistan is integral to the economic development of the country. The nation is largely dependent on the cotton industry and its related textile sector, and the crop has been given a principal status in the country. Cotton is grown as an industrial crop in 15% of the nation's land during the monsoon months of May to August, known as the kharif period, and is grown at a smaller scale between February and April. Record production of cotton was reported at 15 million bales of 470 pounds (210 kg) each in the form of phutti (seed cotton) during 2014–15, which was an 11% rise compared to the previous season (2013–14). Production-wise, as of 2012–13, Pakistan occupied the fourth position among the cotton growers of the world, the first three being China, India and the United States, in that order. In respect of exports of raw cotton, Pakistan holds third position, and is the fourth in consumption (about 30 and 40 per cent of its production). It is the largest exporter of cotton yarn.
  • 4.2K
  • 16 Nov 2022
Topic Review
Early Injection for Low Emissions
Low-emission and high-efficiency have always been the targets for Internal Combustion Engine development. For diesel engines, homogeneous charge (aka. HCCI) and premixed charge (aka. PCCI) combustion modes provide both low-emission and high-efficiency simultaneously. To achieve these advanced combustion modes, early injection is needed as a relatively longer air-fuel mixing time is guaranteed. Several key parameters, such as the injection timing, pressure, angle, directly determine the final combustion process and thus the emission and efficiency performance. The pros and cons of these key parameters are discussed in detail here to provide a good review of the early-injection strategy.
  • 4.2K
  • 28 Oct 2020
Topic Review
Total Petroleum Hydrocarbons in Seawater
Total Petroleum Hydrocarbons (TPH) is a term used to represent petroleum (crude oil) that consists of a blend of thousands of compounds. They are referred to as hydrocarbons because almost all consist of hydrogen and carbon. A crude oil spill is a common issue during offshore oil drilling, transport and transfer to onshore. Second, the production of petroleum refinery effluent is known to cause pollution due to its toxic effluent discharge. Sea habitats and onshore soil biota are affected by TPH as a pollutant in their natural environment. Crude oil pollution in seawater, estuaries and beaches requires an efficient process of cleaning. To remove crude oil pollutants from seawater, various physico-chemical and biological treatment methods have been applied worldwide. A biological treatment method using bacteria, fungi and algae has recently gained a lot of attention due to its efficiency and lower cost.
  • 4.2K
  • 23 Apr 2021
Topic Review
MMP-13 in Osteoarthritis Treatment
Osteoarthritis (OA) is a common degenerative disease characterized by the destruction of articular cartilage and chronic inflammation of surrounding tissues. Matrix metalloproteinase-13 (MMP-13) is the primary MMP involved in cartilage degradation through its particular ability to cleave type II collagen. Hence, it is an attractive target for the treatment of OA.
  • 4.2K
  • 07 May 2021
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