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Topic Review
Polyunsaturated Fatty Acids
Polyunsaturated fatty acids (PUFAs) have more than one double bond between carbon atoms. Omega(ω) indicates the location of the first carbon double bond, counting from the" end "of the molecule (from the methyl group). Therefore, ω-3 fatty acids have a first double bond on the third last carbon. Those from the ω -6 family at the sixth carbon from the bottom. A of the ω -9 family at the ninth carbon atom from the terminal methyl group to the first C = C bond. The designations n – 3, n – 6, n – 9 are also used. The human body is unable to introduce the double bond further than at the ninth carbon.PUFAs can be synthesized in mammals and supplied with the diet, with the exception of α-linolenic (ALA) and linoleic (LA) acids, which must be systematically supplied with food. Therefore, they are referred to as Essential Unsaturated Fatty Acids or Exogenous Unsaturated Fatty Acids. LA and ALA acids are transformed into a family of unsaturated ω-3 and ω-6 acids as a result of elongation and desaturation processes. The following acids are obtained from ALA: stearidine (18: 4, ω – 3), eicosatetraenoic (20: 4, ω – 3), eicosapentaenoic (20: 5, ω – 3) and docosahexaenoic (22: 6, ω – 3). On the other hand, the family of ω-6 acids (LA) is formed, starting from gamma-linolenic acid (18: 3, ω-6), through dihomo-gamma-linolenic acid (18: 3, ω-6), arachidonic acid (20: 4 ω – 6) and docosatetraenoic (22: 4 ω – 6), to docosapentaenoic acid (22: 5, ω – 6).In everyday diets, it is advisable to include sources of polyunsaturated fatty acids, which include vegetable oils (linseed oil, avocado, olive and rapeseed oil), fatty sea fish (herring, salmon, mackerel, halibut) and nuts. In the case of oils, attention should be paid whether they have too much ω-6 in relation to ω-3, because then the harmful pro-aggregating and pro-inflammatory effect may outweigh the anti-aggregation and anti-inflammatory effect. 
  • 2.9K
  • 15 Jan 2021
Topic Review
Spinning of Biopolymer Fibers
Increasing interest in bio-based polymers and fibers has led to the development of several alternatives to conventional plastics and fibers made of these materials. Biopolymer fibers can be made from renewable, environmentally friendly resources and can be fully biodegradable. Biogenic resources with a high content of carbohydrates such as starch-containing plants have huge potentials to substitute conventional synthetic plastics in a number of applications. 
  • 2.9K
  • 06 May 2021
Topic Review
Pharmacological Efficacy of Tamarix aphylla
Tamarix aphylla is a well-known species of the genus Tamarix. T. aphylla (Tamaricaceae) is a perennial tree in Asia, the Middle East, and Central Africa. It is used as a carminative diuretic in tuberculosis, leprosy, and hepatitis. Various pharmacological properties have been shown by T. aphylla, such as antidiabetic, anti-inflammatory, antibacterial, antifungal, anticholinesterase, and wound-healing activity. However, T. aphylla has not received much attention for its secondary metabolites and bioactive constituents. Research has shown that this plant has hidden potential that needs to be explored. 
  • 2.9K
  • 29 Mar 2022
Topic Review
Reading (Process)
User:RMCD bot/subject notice Reading is a complex "cognitive process" of decoding symbols in order to construct or derive meaning (reading comprehension). Reading is a means of language acquisition, communication, and of sharing information and ideas. The symbols are typically visual (written or printed) but may be tactile (Braille). Like all languages, it is a complex interaction between the text and the reader which is shaped by the reader’s prior knowledge, experiences, attitude, and language community which is culturally and socially situated. The reading process requires continuous practice, development, and refinement. In addition, reading requires creativity and critical analysis. Consumers of literature make ventures with each piece, innately deviating from literal words to create images that make sense to them in the unfamiliar places the texts describe. Because reading is such a complex process, it cannot be controlled or restricted to one or two interpretations. There are no concrete laws in reading, but rather it allows readers an escape to produce their own products introspectively. This promotes deep exploration of texts during interpretation. Readers use a variety of reading strategies to assist with decoding (to translate symbols into sounds or visual representations of speech) and comprehension. Readers may use context clues to identify the meaning of unknown words. Readers integrate the words they have read into their existing framework of knowledge or schema. Other types of reading are not speech based writing systems, such as music notation or pictograms. The common link is the interpretation of symbols to extract the meaning from the visual notations or tactile signals (as in the case of Braille).
  • 2.9K
  • 20 Oct 2022
Topic Review
Trace Gas Orbiter
The ExoMars Trace Gas Orbiter (TGO or ExoMars Orbiter) is a collaborative project between the European Space Agency (ESA) and Roscosmos that sent an atmospheric research orbiter and the Schiaparelli demonstration lander to Mars in 2016 as part of the European-led ExoMars programme. The Trace Gas Orbiter delivered the Schiaparelli lander on 16 October 2016, which crashed on the surface. The orbiter began aerobraking in March 2017 to lower its initial orbit of 200 by 98,000 km (120 by 60,890 mi). Aerobraking concluded on 20 February 2018 when a final thruster firing resulted in an orbit of 200 by 1,050 km (120 by 650 mi). Additional thruster firings every few days raised the orbiter to a circular "science" orbit of 400 km (250 mi), which was achieved on 9 April 2018. A key goal is to gain a better understanding of methane (CH4) and other trace gases present in the Martian atmosphere that could be evidence for possible biological activity. The programme will follow with the Kazachok lander and the Rosalind Franklin rover in 2020, which will search for biomolecules and biosignatures; the TGO will operate as the communication link for the ExoMars lander and rover and provide communication for other Mars surface probes with Earth.
  • 2.9K
  • 27 Oct 2022
Topic Review Peer Reviewed
Modulation of the Host Defence System by Nematophagous Fungi and Chitosan
Nematophagous fungi (NFs), which are responsible for soil suppression of plant-parasitic nematodes, are multitrophic biocontrol agents. This raises the question of the transition between lifestyles (e.g., endophytism vs. egg parasitism). The NF Pochonia chlamydosporia colonises food crops and promotes their growth and yield. When colonising the plant, P. chlamydosporia induces the plant immunity (PI). However, it also evades the PI. To do this, both endophytic NF and pathogenic fungi (PF) secrete LysM effectors (LysM-effs). LysM effectors have been shown to have diverse functions in different organisms, including the protection of fungal chitin from plant chitinases. P. chlamydosporia is resistant to chitosan, which modulates gene expression in fungi and plants and has antimicrobial properties. P. chlamydosporia chitin deacetylases (CDA) and chitosanases (CSN) also help P. chlamydosporia evade plant immunity, resist exogenous chitosan, and are induced during fungal infection of nematode eggs. NF-chitosan formulations are new biomanagement tools against plant parasitic nematodes, fungal wilt pathogens and insect pests that currently threaten food security crops. Furthermore, omics techniques are useful tools to elucidate the role of CDAs, CSNs, LysM-effs, adhesion proteins and carbohydrate-active enzymes in pathogen–BCA–plant interactions, adhesion and infection to nematode eggs and their modulation by chitosan.
  • 2.9K
  • 21 Feb 2024
Topic Review
Olmec Influences on Mesoamerican Cultures
The causes and degree of Olmec influences on Mesoamerican cultures has been a subject of debate over many decades. Although the Olmecs are considered to be perhaps the earliest Mesoamerican civilization, there are questions concerning how and how much the Olmecs influenced cultures outside the Olmec heartland. This debate is succinctly, if simplistically, framed by the title of a 2005 The New York Times article: “Mother Culture, or Only a Sister?”.
  • 2.9K
  • 14 Oct 2022
Topic Review
Wireless Sensor Networks
Wireless sensor networks (WSNs) are spatially scattered networks equipped with an extensive number of nodes to check and record different ecological states such as humidity, temperature, pressure, and lightning states. WSN network provides different services to a client such as monitoring, detection, and runtime decision-making against events occurrence.
  • 2.9K
  • 02 Nov 2021
Topic Review
History of Delphi
This page details the history of the programming language and software product Delphi.
  • 2.9K
  • 17 Nov 2022
Topic Review
Radioactivity in Plastic Materials
All fossil combustible materials, such as coal and crude oil, contain radioactive elements, which origin from the natural decay series of uranium and thorium. The basic material for the synthesis of plastics is crude oil. Therefore, plastics may contain radionuclides. The gamma ray analysis of different rubbish bags used in the city of Basel show a clear contamination with uranium, radium (226Ra and 228Ra) and lead (210Pb), resulting in a yearly charge of 300, 300, 150 and 3,000 MBq each. In comparison with the contamination level of the burning ashes, these charges are not relevant (less than 1% of the content in the slags from the waste incineration). Nonetheless, we note a permanent displacement of long-lived natural radionuclides to landfill-sites.
  • 2.9K
  • 05 Jul 2021
Topic Review
Wireless Battery Management System Topologies
An effective battery management system (BMS) is indispensable for any lithium-ion battery (LIB) powered systems such as electric vehicles (EVs) and stationary grid-tied energy storage systems. Massive wire harness, scalability issue, physical failure of wiring, and high implementation cost and weight are some of the major issues in conventional wired-BMS. One of the promising solutions researchers have come up with is the wireless BMS (WBMS) architecture. Despite research and development on WBMS getting momentum more than a decade ago, it is still in a preliminary stage. Significant further upgradation is required towards developing an industry-ready WBMS, especially for high-power LIB packs.
  • 2.9K
  • 22 Sep 2021
Topic Review
Side Lobe
In antenna engineering, side lobes or sidelobes are the lobes (local maxima) of the far field radiation pattern of an antenna or other radiation source, that are not the main lobe. The radiation pattern of most antennas shows a pattern of "lobes" at various angles, directions where the radiated signal strength reaches a maximum, separated by "nulls", angles at which the radiated signal strength falls to zero. This can be viewed as the diffraction pattern of the antenna. In a directional antenna in which the objective is to emit the radio waves in one direction, the lobe in that direction is designed to have a larger field strength than the others; this is the "main lobe". The other lobes are called "side lobes", and usually represent unwanted radiation in undesired directions. The side lobe directly behind the main lobe is called the back lobe. The longer the antenna relative to the radio wavelength, the more lobes its radiation pattern has. In transmitting antennas, excessive side lobe radiation wastes energy and may cause interference to other equipment. Another disadvantage is that confidential information may be picked up by unintended receivers. In receiving antennas, side lobes may pick up interfering signals, and increase the noise level in the receiver. The power density in the side lobes is generally much less than that in the main beam. It is generally desirable to minimize the sidelobe level (SLL), which is measured in decibels relative to the peak of the main beam. The main lobe and side lobes occur for both transmitting and receiving. The concepts of main and side lobes, radiation pattern, aperture shapes, and aperture weighting, apply to optics (another branch of electromagnetics) and in acoustics fields such as loudspeaker and sonar design, as well as antenna design. Because an antenna's far field radiation pattern is a Fourier Transform of its aperture distribution, most antennas will generally have sidelobes, unless the aperture distribution is a Gaussian, or if the antenna is so small as to have no sidelobes in the visible space. Larger antennas have narrower main beams, as well as narrower sidelobes. Hence, larger antennas have more sidelobes in the visible space (as the antenna size is increased, sidelobes move from the evanescent space to the visible space).
  • 2.9K
  • 28 Nov 2022
Topic Review
Gender Disparities in the Urban Public Transport
Gender and public transportation studies are critical for a nation’s social and economic development, particularly in a developing country such as Nigeria. Men and women use public transportation due to their different social roles and economic activities. In other words, good public transportation improves or expands opportunities in health, education, and employment. Consequently, understanding the gender differences in accessibility will be crucial to enhancing existing transport services and helping design more efficient transport policies. 
  • 2.9K
  • 23 Jun 2025
Topic Review
Biogenic amines in Fish
The occurrence of biogenic amines in fish is directly associated with microorganisms with decarboxylase activity. These compounds are generally detoxified by oxidases in the intestinal tract of humans, but some conditions, such as alcohol consumption, enzyme deficiency, or monoamino-oxidase antidepressant use, can make their intake by food dangerous. Due to its toxicity, histamine is a unique biogenic amine with regulatory limits for fishery products. This review focuses on biogenic amines in fish, with a detailed picture of the number of alert notifications or intoxication events reported in the last years. The favoring conditions for their formation, as well as the main preventive and control measures to ensure public health, are also reviewed.
  • 2.9K
  • 18 Dec 2020
Topic Review
High-Spectral-Resolution Lidar
High-spectral-resolution lidar (HSRL) is a powerful tool for atmospheric aerosol remote sensing. A ground-based high-spectral-resolution lidar (HSRL), operated at 532 nm wavelength, has been developed at Zhejiang University (ZJU) for aerosols and clouds studies. This lidar provides vertical profiles of aerosol scattering ratio together with lidar ratio and particle depolarization ratio at 532 nm. Determination of overlap function is a key step in the calibration of a high-spectral-resolution lidar (HSRL) and important guarantee of data retrieval, an iterative-based general determination (IGD) method for overlap function in HSRL is proposed. The standard method to retrieve the extinction coefficient from HSRL signals depends heavily on the signal-to-noise ratio (SNR). An iterative image reconstruction (IIR) method is proposed for the retrieval of the aerosol extinction coefficient based on HSRL data under low SNR condition. With the optical properties, a state-of-the-art method for feature detection and classification is proposed to automatically identify the features attributed to dust/polluted dust, urban/smoke, maritime aerosols, as well as ice and liquid water cloud during day and night.
  • 2.9K
  • 22 Feb 2021
Topic Review
Masstige Luxury Buying Behavior
The luxury product market has experienced a rapid growth in the last twenty years in the world. A new model derived from Behavioral Reasoning Theory (BRT) to examine the purchasing behavior of masstige jewelry consumers. The suggested model provides a more comprehensive understanding of the determinants of purchasing masstige products by considering values and reasons in addition to the global motives and intention.
  • 2.9K
  • 07 Feb 2024
Topic Review
NASDAQ
The Nasdaq Stock Market (/ˈnæzˌdæk/ (listen), also known simply as Nasdaq) is an American stock exchange. It is the second-largest exchange in the world by market capitalization, behind only the New York Stock Exchange located in the same city. The exchange platform is owned by Nasdaq, Inc., which also owns the Nasdaq Nordic (formerly known as OMX) and Nasdaq Baltic stock market network and several U.S. stock and options exchanges
  • 2.9K
  • 30 Nov 2022
Topic Review
Pd-Catalyzed Homogeneous Tandem Processes
Pd-containing catalytic systems for tandem processes have gained special attention due to their enhanced catalytic properties and their possibility of performing several reactions without the necessity of separating the intermediates.
  • 2.9K
  • 24 Aug 2023
Topic Review
Subject
A subject is a being who has a unique consciousness and/or unique personal experiences, or an entity that has a relationship with another entity that exists outside itself (called an "object"). A subject is an observer and an object is a thing observed. This concept is especially important in Continental philosophy, where 'the subject' is a central term in debates over the nature of the self. The nature of the subject is also central in debates over the nature of subjective experience within the Anglo-American tradition of analytical philosophy. The sharp distinction between subject and object corresponds to the distinction, in the philosophy of René Descartes, between thought and extension. Descartes believed that thought (subjectivity) was the essence of the mind, and that extension (the occupation of space) was the essence of matter.
  • 2.9K
  • 18 Nov 2022
Topic Review
Granular Organic Fertilizers
Granular organic fertilizers' production has recently become more popular, with the main aim of converting high-moisture organic matter, such as manure, manure mixtures, meat and bone waste or other organic matter, into pellets that are convenient to spread in the field. The pellets are usually produced with the diameter of 4 or 6 mm so that they can be easily spread with mineral or organic fertilizer spreaders. Once in the soil, organic fertilizer pellets become wet, decompose and release nutrients.
  • 2.9K
  • 11 Sep 2021
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