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Topic Review

Kenneth Thomas Cuccinelli II (/ˈkuːtʃɪˈnɛli/ KOO-chi-NEL-ee; born July 30, 1968) is an American politician and lawyer currently serving as Principal Deputy Director of the U.S. Citizenship and Immigration Services (USCIS) agency and Acting Deputy Secretary of Homeland Security. He previously served as the 46th attorney general of Virginia from 2010 until 2014, and acting Director of USCIS agency. Before this, he was in the Virginia Senate, representing the 37th district in Fairfax County from 2002 until he took office as attorney general in 2010. On May 18, 2013, Cuccinelli won the Republican Party's gubernatorial nomination at the state party convention. Cuccinelli was the Republican nominee for Governor of Virginia in the 2013 Virginia gubernatorial election, losing to the Democratic nominee, Terry McAuliffe, by 56,435 votes or 2.5% of the total votes cast. A self-described opponent of homosexuality, Cuccinelli in his position as Virginia Attorney General defended anti-sodomy laws and prohibitions on same-sex marriage. Cuccinelli rejects the scientific consensus on climate change, and in his position as Attorney General investigated climate scientists whom he accused of fraud. He filed lawsuits against the Obama administration’s Environmental Protection Agency. Characterized as an immigration hard-liner, Cuccinelli sought to prohibit undocumented immigrants from attending universities, repeal birthright citizenship, and force employees to speak English in the workplace. As CIS Director, he implemented and defended policies that would reject applications for visas or permanent residency for immigrants considered likely to utilize publicly funded benefits programs.

3.4K
12 Oct 2022

Topic Review

The atomic radius of a chemical element is a measure of the size of its atom, usually the mean or typical distance from the center of the nucleus to the outermost isolated electron. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. Four widely used definitions of atomic radius are: Van der Waals radius, ionic radius, metallic radius and covalent radius. Typically, because of the difficulty to isolate atoms in order to measure their radii separately, atomic radius is measured in a chemically bonded state; however theoretical calculations are simpler when considering atoms in isolation. The dependencies on environment, probe, and state lead to a multiplicity of definitions. Depending on the definition, the term may apply to atoms in condensed matter, covalently bonding in molecules, or in ionized and excited states; and its value may be obtained through experimental measurements, or computed from theoretical models. The value of the radius may depend on the atom's state and context. Electrons do not have definite orbits nor sharply defined ranges. Rather, their positions must be described as probability distributions that taper off gradually as one moves away from the nucleus, without a sharp cutoff; these are referred to as atomic orbitals or electron clouds. Moreover, in condensed matter and molecules, the electron clouds of the atoms usually overlap to some extent, and some of the electrons may roam over a large region encompassing two or more atoms. Under most definitions the radii of isolated neutral atoms range between 30 and 300 pm (trillionths of a meter), or between 0.3 and 3 ångströms. Therefore, the radius of an atom is more than 10,000 times the radius of its nucleus (1–10 fm), and less than 1/1000 of the wavelength of visible light (400–700 nm). For many purposes, atoms can be modeled as spheres. This is only a crude approximation, but it can provide quantitative explanations and predictions for many phenomena, such as the density of liquids and solids, the diffusion of fluids through molecular sieves, the arrangement of atoms and ions in crystals, and the size and shape of molecules.

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18 Oct 2022

Topic Review

Fish Skin Mucus Extracts as Antimicrobial Agents

The slow discovery of new antibiotics combined with the alarming emergence of antibiotic-resistant bacteria underscores the need for alternative treatments. In this regard, fish skin mucus has been demonstrated to contain a diverse array of bioactive molecules with antimicrobial properties, including peptides, proteins, and other metabolites. This entry aims to provide an overview of the antimicrobial molecules found in fish skin mucus and its reported in vitro antimicrobial capacity against bacteria, fungi, and viruses. Additionally, the different methods of mucus extraction, which can be grouped as aqueous, organic, and acidic extractions, are presented. Finally, omic techniques (genomics, transcriptomics, proteomics, metabolomics, and multiomics) are described as key tools for the identification and isolation of new antimicrobial compounds.

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19 Jun 2023

Topic Review

Struvite Precipitation Technologies

The abatement of nutrient compounds from aqueous waste and wastewater is currently a priority issue. Indeed, the uncontrolled discharge of high levels of nutrients into water bodies causes serious deteriorations of environmental quality. On the other hand, the increasing request of nutrient compounds for agronomic utilizations makes it strictly necessary to identify technologies able to recover the nutrients from wastewater streams so as to avoid the consumption of natural resources. In this regard, the removal and recovery of nitrogen and phosphorus from aqueous waste and wastewater as struvite (MgNH4PO4·6H2O) represents an attractive approach. Indeed, through the struvite precipitation it is possible to effectively remove the ammonium and phosphate content of many types of wastewater and to produce a solid compound, with only a trace of impurities. This precipitate, due to its chemical characteristics, represents a valuable multi-nutrients slow release fertilizer for vegetables and plants growth. For these reasons, the struvite precipitation technology constantly progresses on several aspects of the process.

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08 Feb 2021

Topic Review Peer Reviewed

The Mysteries of the White Truffle: Its Biology, Ecology and Cultivation

Tuber magnatum Picco is the most expensive of the truffles and a great deal of research has been carried out in an attempt to solve the mysteries of its ecology and biology. However, considerable work remains to be done particularly on those secrets of its life cycle that remain a mystery. It is known that T. magnatum is heterothallic, but it has yet to be determined how fertilization occurs between the two strains of different mating types. It is also known that the white truffle is an ectomycorrhizal fungus, and its mycorrhizas can be produced in greenhouses, but then they seem to disappear in the field. The role of other soil microorganisms, fungi and bacteria, on its soil mycelial development and fructification is intriguing but is far from being completely understood. All these uncertainties have made the cultivation of T. magnatum extremely difficult and only recently have we had the scientific proofs that it is possible. Even so, many questions remain unanswered and the management practices of T. magnatum plantations are still to be better defined to also enable the taming of this truffle.

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11 Jan 2023

Topic Review Peer Reviewed

Saccharomyces cerevisiae: Multifaceted Applications in One Health and the Achievement of Sustainable Development Goals

Saccharomyces cerevisiae (SC), a yeast with an extensive history in food and beverage fermentations, is increasingly acknowledged for its multifaceted application in promoting and benefiting all aspects of a ‘One Health’ approach, including the prevention and control of zoonoses. For instance, SC contributes to environmentally sustainable agricultural practices through the reduced use of toxic agents, thus minimizing air and soil pollution while enhancing crop quality. Additionally, this versatile yeast can improve the health of domestic and farm animals, leading to more efficient and sustainable food production, while fostering synergistic impacts across environmental, animal, and human health spheres. Moreover, SC directly applies benefits to human health by promoting improved nutrition, improving gut health through probiotics, as an alternative to antibiotics, and treating gastric disorders. By aligning with several Sustainable Development Goals (SDGs), SC is vital in advancing global health and well-being, environmental sustainability, and responsible consumption and production. This entry illustrates the numerous benefits of SC and highlights its significant impact on a global ‘One Health’ scale, promoting the achievement of SDGs through its unique characteristics and deeper understanding of its contribution to the One Health concept.

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16 May 2023

Topic Review

Protein Consumption and Income Growth

Consumption and production of proteins derived from animals have more significant environmental and health impacts than proteins derived from plants. This raises concerns mainly in consideration of the predictable increased consumption of animal proteins at the expense of vegetal ones due to growing income, especially in developing countries. Animal protein consumption, and particularly meat consumption, seems to start to decrease at a high level of income, which may suggest that economic growth solves or attenuates the environmental and health problems of animal food consumption. Though there is actually some evidence of an inverted U-shaped relationship between per capita income and animal protein consumption, the peak is at such high levels as to make economic growth irrelevant to curb animal protein consumption.

3.4K
06 Sep 2021

Topic Review

Beam-Squinting Effect in Broadband Mobile Communication

Due to the fact that the quality of the received signal is adversely affected by the beam squint phenomenon, which is especially pertinent to the millimeter wave (mmwave) bands, many studies have been utilised by other researchers to provide light on some of the challenges that come with analysing this type of occurrence. Squint causes several issues, the most important of which are its detrimental effects on gain, line of sight, angle of arrival, progressive phase, usable bandwidth, and fading effect. As a result of these obstacles, the advantages of adopting a high-frequency band such as mmwave in modern wireless communication systems are severely limited.

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06 Feb 2023

Topic Review

Hydrogen Storage Techniques for On-Board Applications

Hydrogen as an energy carrier could help decarbonize industrial, building, and transportation sectors, and be used in fuel cells to generate electricity, power, or heat. One of the numerous ways to solve the climate crisis is to make the vehicles on our roads as clean as possible. Fuel cell electric vehicles (FCEVs) have demonstrated a high potential in storing and converting chemical energy into electricity with zero carbon dioxide emissions. This text presents the most favorable hydrogen storage approaches for FCEV on-board applications. To achieve long-range autonomy (over 500 km), FCEVs must be capable of storing 5-10 kg of hydrogen in compressed vessels at 700 bar, with Type IV vessels being the primary option. Although physical and chemical storage technologies are expected to be valuable to the hydrogen economy, compressed hydrogen storage remains the most advanced technology for on-board applications.

3.4K
09 Aug 2023

Topic Review

Modified Frequency Modulation

Modified Frequency Modulation, commonly MFM, is a run-length limited (RLL) coding scheme used to encode the actual data-bits on most floppy disks. It was first introduced in disk drives with the IBM 3330 hard disk drive in 1970. Floppy disk drive hardware examples include Amiga, most CP/M machines as well as IBM PC compatibles. MFM is a modification to the original digital FM (digital frequency modulation also known as delay coding) scheme for encoding data on single-density floppy disks and some early hard disk drives. Due to the minimum spacing between flux transitions that is a property of the disk, head and channel design, MFM, which guarantees at most one flux transition per data bit, can be written at higher density than FM, which can require two transitions per data bit. It is used with a data rate of 250–500 kbit/s (500–1000 kbit/s encoded) on industry standard 5¼-inch and 3½-inch ordinary and high density diskettes. MFM was also used in early hard disk designs, before the advent of more efficient types of run-length limited codes. Except for the steadily disappearing 360 KiB/1.2 MiB (5.25-inch) and 720~880 KiB/1.4~1.6 MiB (3.5-inch) floppy disk formats, MFM encoding is obsolete in magnetic recording.

3.4K
22 Nov 2022

Topic Review Peer Reviewed

The Principle of Action and Reaction According to Newton

The principle of action and reaction is generally considered the least problematic and interesting of Newton’s three laws of dynamics—least problematic because it seems self-evident, and least interesting because Newton’s mechanics of Principia essentially represents the dynamics of a mass point, while the principle of action and reaction is mainly important in the case of a set of bodies that interact with each other. However, reading Newton’s text is enough for the principle to appear equally problematic and interesting as the other two. This entry aims to justify this statement and to help clarify the meaning of the principle.

3.4K
13 Jun 2023

Topic Review

Zero-Waste Manufacturing

At first glance, zero waste (ZW) means complete and total elimination or absence of waste. However, much more than that, ZW entails waste prevention and where all materials are reused. It is a philosophy that forbids sending any unused material to landfills, dumpsites, or incinerators.

3.4K
16 May 2022

Topic Review

Sustainable Leadership Practices and Competencies of SMEs

Sustainability leadership has gained much popularity as an emergent multidisciplinary area in the recent literature. Worldwide scholars call for more sustainability studies as an important leadership agenda . Modern leaders need to strategically lead their businesses beyond profit-maximization or economic performance and maneuver their vision and strategy toward environmental protection and social responsibility. The literature urges future leaders and managers to purposefully develop value-oriented sustainable leadership and sustainability competencies in their business practices as well as to balance the economic performance and socio-environmental responsibility to thrive for long-term success. The latest empirical research also indicates that sustainability leadership is a key determinant of long-term success and sustainability performance outcomes. The topic strategically becomes critical to achieve corporate resilience, longevity and sustainable futures.

3.4K
15 Jun 2022

Topic Review

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a large-scale physics experiment and observatory to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. Two large observatories were built in the United States with the aim of detecting gravitational waves by laser interferometry. These can detect a change in the 4 km mirror spacing of less than a ten-thousandth the charge diameter of a proton, equivalent to measuring the distance from Earth to Proxima Centauri (4.0208x1013km) with an accuracy smaller than the width of a human hair. The initial LIGO observatories were funded by the National Science Foundation (NSF) and were conceived, built, and are operated by Caltech and MIT. They collected data from 2002 to 2010 but no gravitational waves were detected. The Advanced LIGO Project to enhance the original LIGO detectors began in 2008 and continues to be supported by the NSF, with important contributions from the UK Science and Technology Facilities Council, the Max Planck Society of Germany, and the Australian Research Council. The improved detectors began operation in 2015. The detection of gravitational waves was reported in 2016 by the LIGO Scientific Collaboration (LSC) and the Virgo Collaboration with the international participation of scientists from several universities and research institutions. Scientists involved in the project and the analysis of the data for gravitational-wave astronomy are organized by the LSC, which includes more than 1000 scientists worldwide, as well as 440,000 active Einstein@Home users (As of December 2016). LIGO is the largest and most ambitious project ever funded by the NSF. In 2017, the Nobel Prize in Physics was awarded to Rainer Weiss, Kip Thorne and Barry C. Barish "for decisive contributions to the LIGO detector and the observation of gravitational waves." "The Nobel Prize in Physics 2017". Nobel Foundation. https://www.nobelprize.org/nobel_prizes/physics/laureates/2017/press.html. As of March 2018, LIGO has made six detections of gravitational waves, of which the first five were colliding black-hole pairs. The sixth detected event, on August 17, 2017, was the first detection of a collision of two neutron stars, which simultaneously produced optical signals detectable by conventional telescopes.

3.4K
25 Oct 2022

Topic Review

Intersection (Euclidean Geometry)

In geometry, an intersection is a point, line, or curve common to two or more objects (such as lines, curves, planes, and surfaces). The simplest case in Euclidean geometry is the intersection of two distinct lines, which either is one point or does not exist if the lines are parallel. Determination of the intersection of flats – linear geometric objects embedded in a higher-dimensional space – is a simple task of linear algebra, namely the solution of a system of linear equations. In general the determination of an intersection leads to non-linear equations, which can be solved numerically, for example using Newton iteration. Intersection problems between a line and a conic section (circle, ellipse, parabola, etc.) or a quadric (sphere, cylinder, hyperboloid, etc.) lead to quadratic equations that can be easily solved. Intersections between quadrics lead to quartic equations that can be solved algebraically.

3.4K
31 Oct 2022

Topic Review

Nrf2 Signaling Pathway

Nrf2 and its principal negative regulator, the E3 ligase adaptor Kelch-like ECH- associated protein 1 (Keap1), play a central role in the maintenance of intracellular redox homeostasis and regulation of inflammation. Interestingly, Nrf2 is proven to contribute to the regulation of the heme oxygenase-1 (HO-1) axis, which is a potent anti-inflammatory target. Recent studies showed a connection between the Nrf2/antioxidant response element (ARE) system and the expression of inflammatory mediators, NF-κB pathway and macrophage metabolism. Thus, Nrf2 is part of a multilayered network that plays a key role in redox homeostasis as well as in inflammation. This suggests a new strategy for designing chemical agents as modulators of Nrf2 dependent pathways to target the immune response.

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15 Dec 2020

Topic Review

Diabetic Wound Healing

Diabetes mellitus (DM) is a common endocrine disease characterized by a state of hyperglycemia (higher level of glucose in the blood than usual). DM and its complications can lead to diabetic foot ulcer (DFU). DFU is associated with impaired wound healing, due to inappropriate cellular and cytokines response, infection, poor vascularization, and neuropathy. Effective therapeutic strategies for the management of impaired wound could be attained through a better insight of molecular mechanism and pathophysiology of diabetic wound healing. Nanotherapeutics-based agents engineered within 1–100 nm levels, which include nanoparticles and nanoscaffolds, are recent promising treatment strategies for accelerating diabetic wound healing. Nanoparticles are smaller in size and have high surface area to volume ratio that increases the likelihood of biological interaction and penetration at wound site. They are ideal for topical delivery of drugs in a sustained manner, eliciting cell-to-cell interactions, cell proliferation, vascularization, cell signaling, and elaboration of biomolecules necessary for effective wound healing. Furthermore, nanoparticles have the ability to deliver one or more therapeutic drug molecules, such as growth factors, nucleic acids, antibiotics, and antioxidants, which can be released in a sustained manner within the target tissue. This review focuses on recent approaches in the development of nanoparticle-based therapeutics for enhancing diabetic wound healing.

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13 Jul 2020

Topic Review

Agriculture in Marginal Lands

The term ‘marginal’ was originally used under the umbrella of economic theorizing to describe an area under given conditions where cost-effective production is not remunerated. Since then, different definitions describing the concept of marginality and marginal environments have emerged, highlighting the complex nature of marginality and how various unfavorable conditions disadvantage individuals and communities living in these areas. In the context of the agricultural economy, the term “margins of cultivation” is used to describe economically marginal agricultural lands where revenue from optimal production just equals (or is lower than, in some instances) the costs of production, leading to zero (negative) profit or economic loss. To capture this specific economic context, FAO and UNEP have classified land supporting a yield of only up to 40 percent of its productivity potential as marginal. Marginal lands are also identified as areas where “cost-effective production is not possible under given conditions, cultivation techniques, agriculture policies, and macro-economic and legal settings”. In this context, economically marginal land can be thought of as land that would not be cultivated at current output and input prices without the availability of government support programs. Marginal lands are mostly abandoned, as they are disadvantaged due to factors such as changing commodity markets, international competition, or the demographics of land owners and farm operators.

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07 Sep 2021

Topic Review

The Plesiosauria (/ˌpliːsiəˈsɔːriə, -zi-/; Greek: πλησίος, plesios, meaning "near to" and sauros, meaning "lizard") or plesiosaurs are an order or clade of extinct Mesozoic marine reptiles, belonging to the Sauropterygia. Plesiosaurs first appeared in the latest Triassic Period, possibly in the Rhaetian stage, about 203 million years ago. They became especially common during the Jurassic Period, thriving until their disappearance due to the Cretaceous–Paleogene extinction event at the end of the Cretaceous Period, about 66 million years ago. They had a worldwide oceanic distribution. Plesiosaurs were among the first fossil reptiles discovered. In the beginning of the nineteenth century, scientists realised how distinctive their build was and they were named as a separate order in 1835. The first plesiosaurian genus, the eponymous Plesiosaurus, was named in 1821. Since then, more than a hundred valid species have been described. In the early twenty-first century, the number of discoveries has increased, leading to an improved understanding of their anatomy, relationships and way of life. Plesiosaurs had a broad flat body and a short tail. Their limbs had evolved into four long flippers, which were powered by strong muscles attached to wide bony plates formed by the shoulder girdle and the pelvis. The flippers made a flying movement through the water. Plesiosaurs breathed air, and bore live young; there are indications that they were warm-blooded. Plesiosaurs showed two main morphological types. Some species, with the "plesiosauromorph" build, had (sometimes extremely) long necks and small heads; these were relatively slow and caught small sea animals. Other species, some of them reaching a length of up to seventeen metres, had the "pliosauromorph" build with a short neck and a large head; these were apex predators, fast hunters of large prey. The two types are related to the traditional strict division of the Plesiosauria into two suborders, the long-necked Plesiosauroidea and the short-neck Pliosauroidea. Modern research, however, indicates that several "long-necked" groups might have had some short-necked members or vice versa. Therefore, the purely descriptive terms "plesiosauromorph" and "pliosauromorph" have been introduced, which do not imply a direct relationship. "Plesiosauroidea" and "Pliosauroidea" today have a more limited meaning. The term "plesiosaur" is properly used to refer to the Plesiosauria as a whole, but informally it is sometimes meant to indicate only the long-necked forms, the old Plesiosauroidea.

3.4K
29 Nov 2022

Topic Review

Template:Infobox bible chapter Numbers 31 is the 31st chapter of the Book of Numbers, the fourth book of the Pentateuch or Torah, the central part of the Hebrew Bible or Old Testament, a sacred text in Judaism and Christianity. Scholars such as Israel Knohl and Dennis T. Olson name this chapter the War against the Midianites. Numbers 31, set in the southern Transjordanian regions of Moab and Midian, narrates how an army of Israelite soldiers commanded by Phinehas (commissioned by Moses and Phinehas' father Eleazar) waged a war against the Midianites, killing all men and boys including their five kings, and taking all livestock, women and girls captive. Moses instructed the soldiers to kill all women who had ever had sex with a man, and to keep the women and girls who were still virgins for themselves. The spoils of war were then divided between the Israelite civilians, soldiers and the god Yahweh. Much scholarly and religious controversy exists surrounding the authorship, meaning and morality of this chapter of Numbers. It is closely connected to Numbers 25.:69

3.4K
01 Dec 2022

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