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Topic Review
Cross-Coupling-Reaction of Copper Carbene Intermediate with Terminal Alkyne
Copper-catalyzed cross-coupling reaction of a copper carbene intermediate with terminal alkynes was one of the most powerful protocols for the construction of C–C bonds. However, in early works, a mixture of alkynoates and allenoates was generated in combined moderate yields under harsh reaction conditions. Until 2004, Fu reported the first example of the copper-catalyzed coupling reaction of terminal alkynes with diazo esters or diazo amides to yield 3-alkynoate or 3-butynamide products selectively with minimal amount of allene byproducts under no-basic conditions. Consequently, a variety of copper-catalyzed coupling reactions of terminal alkynes with various carbene precursors have been developed independently.
  • 3.8K
  • 30 May 2022
Topic Review
Plastic Packaging Recycling
Today, the scientific community is facing crucial challenges in delivering a healthier world for future generations. Among these, the quest for circular and sustainable approaches for plastic recycling is one of the most demanding for several reasons. Indeed, the massive use of plastic materials over the last century has generated large amounts of long-lasting waste, which, for much time, has not been object of adequate recovery and disposal politics. Most of this waste is generated by packaging materials. Nevertheless, in the last decade, a new trend imposed by environmental concerns brought this topic under the magnifying glass, as testified by the increasing number of related publications. Several methods have been proposed for the recycling of polymeric plastic materials based on chemical or mechanical methods. A panorama of the most promising studies related to the recycling of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polystyrene (PS) is given within this review. 
  • 3.8K
  • 16 Sep 2021
Topic Review
Airsacculitis
Airsacculitis, also known as air sacculitis, aerosacculitis, air sac disease, air sac infection, air sac syndrome and simply sac disease, is a common inflammatory condition of air sacs that occurs in birds and is caused by various microbial (mostly bacterial) taxa. Having multiple different causative agents, the condition is widely distributed around the world. Since the disease is highly infectious it is especially dangerous for domesticated birds (poultry) bred on big farms. Occurrence of airsacculitis in big flocks can mean high economic loss, as infected poultry needs to be carefully observed, with all of the infected tissue disposed of and not used for human food. In severe cases of the disease whole infected bird carcasses need to be disposed. Usually the disease affects younger birds, aged between 6 and 12 weeks. The most characteristic sign of airsacculitis is an inflamed mucous membrane of bird air sacs, which swells and becomes red, with infected birds exhibiting different symptoms, such as coughing, lethargy, swelling of the neck, difficult breathing, appetite and weight loss etc. The same term is used for bacterial infection and subsequent inflammation of laryngeal air sacs in non-human primates.
  • 3.8K
  • 25 Oct 2022
Topic Review Peer Reviewed
The Barnett Critique
The Barnett critique states that there is an internal inconsistency between the theory that is implied by simple sum monetary aggregation (perfect substitutability among components) and the economic theory that produces the models within which those aggregates are used. That inconsistency causes the appearance of unstable demand and supply for money. The incorrect inference of unstable money demand has caused serious harm to the field of monetary economics.
  • 3.8K
  • 13 Apr 2022
Topic Review
Positive Psychotherapy
Positive psychotherapy (PPT after Peseschkian, since 1977)TM is a psychotherapeutic method developed by psychiatrist Nossrat Peseschkian and co-workers in Germany beginning in 1968. It can be described as a humanistic psychodynamic psychotherapy, which is based on a positive conception of human nature. The focus of positive psychotherapy is to enhance the positive emotion and engagement of patients rather than targeting the depressive symptoms PPT is an integrative method which includes humanistic, systemic, psychodynamic and CBT-elements. Today there are centers and trainings in some twenty countries worldwide. It should not be confused with positive psychology.
  • 3.8K
  • 22 Nov 2022
Topic Review
Biomechanical Aspects at Dental Implant-Abutment Interfaces
The interface between a dental implant and an abutment is stabilized by two mechanical characteristics: a preload of an abutment screw and the friction between the contact surfaces of the implant and the abutment. These mechanical properties are quantitatively analyzed by using physical and mechanical formulas. The important thing is that such mechanical properties cause various biological phenomena when medical devices are inserted into human bodies. Some mechanical complications in dental implant prostheses are closely associated with biological complications.
  • 3.8K
  • 13 Jun 2023
Topic Review
GeForce 4 Series
The GeForce 4 series (codenames below) refers to the fourth generation of GeForce-branded graphics processing units (GPUs) manufactured by Nvidia. There are two different GeForce4 families, the high-performance Ti family, and the budget MX family. The MX family spawned a mostly identical GeForce4 Go (NV17M) family for the laptop market. All three families were announced in early 2002; members within each family were differentiated by core and memory clock speeds. In late 2002, there was an attempt to form a fourth family, also for the laptop market, the only member of it being the GeForce4 4200 Go (NV28M) which was derived from the Ti line.
  • 3.8K
  • 21 Oct 2022
Topic Review
Food Composition Databases
Food databases (FDB), or more correctly food composition databases, contain detailed information on the nutritional composition of foods and on other relevant compounds (e.g., polyphenols, phytic acid). Food components primarily determine nutritional features and, in some cases, quality aspects. For example, polyphenols, which are abundant in plants, are often associated to bitter taste and astringency sensation of foods, while acting in favour of food safety by inhibiting foodborne pathogens and spoilage microbes.
  • 3.8K
  • 13 Sep 2021
Topic Review
Angra Mainyu
Angra Mainyu (/ˈæŋrə ˈmaɪnjuː/) is the Avestan-language name of Zoroastrianism's hypostasis of the "destructive spirit". The Middle Persian equivalent is Ahriman 𐭠𐭧𐭫𐭬𐭭𐭩‎ (Anglicised pronunciation: /ˈɑːrɪmən/). Angra Mainyu is omnimalevolent. Angra Mainyu is Ahura Mazda’s adversary.
  • 3.8K
  • 04 Nov 2022
Topic Review
Types of Pipeline Anomalies
Pipelines are considered the most efficient way to transport oil and gas resources. However, this advantage of pipelines may be lost if pipeline integrity is not ensured. Geometric deformations, metal losses, and crack-type anomalies caused by various reasons in the pipeline threaten the integrity of the pipeline. Therefore, it is important to examine the causes of occurrence, hazard potentials, and management methods of pipeline anomalies as part of pipeline integrity management. 
  • 3.8K
  • 27 Apr 2023
Topic Review
Speech and Craniofacial Development
Speech is a communication method found only in humans that relies on precisely articulated sounds to encode and express thoughts. Anatomical differences in the maxilla, mandible, tooth position, and vocal tract affect tongue placement and broadly influence the patterns of airflow and resonance during speech production. Alterations in these structures can create perceptual distortions in speech known as speech sound disorders (SSDs). As craniofacial development occurs, the vocal tract, jaws, and teeth change in parallel with stages of speech development, from babbling to adult phonation. Alterations from a normal Class 1 dental and skeletal relationship can impact speech. Dentofacial disharmony (DFD) patients have jaw disproportions, with a high prevalence of SSDs, where the severity of malocclusion correlates with the degree of speech distortion.
  • 3.8K
  • 06 May 2023
Topic Review Peer Reviewed
Metal Binding Proteins
Metal ions play several major roles in proteins: structural, regulatory, and enzymatic. The binding of some metal ions increase stability of proteins or protein domains. Some metal ions can regulate various cell processes being first, second, or third messengers. Some metal ions, especially transition metal ions, take part in catalysis in many enzymes. From ten to twelve metals are vitally important for activity of living organisms: sodium, potassium, magnesium, calcium, manganese, iron, cobalt, zinc, nickel, vanadium, molybdenum, and tungsten. This short review is devoted to structural, physical, chemical, and physiological properties of proteins, which specifically bind these metal cations.
  • 3.8K
  • 18 Apr 2022
Topic Review
Urban Land Use Planning
Urbanization is persistent globally and has increasingly significant spatial and environmental consequences. It is especially challenging in developing countries due to the increasing pressure on the limited resources, and damage to the bio-physical environment.
  • 3.8K
  • 13 Oct 2021
Topic Review
Iron and Iron Overload in Invasive Fungal Infections
Iron is an essential trace metal necessary for the reproduction and survival of fungal pathogens. The latter have developed various mechanisms to acquire iron from their mammalian hosts, with whom they participate in a continuous struggle for dominance over iron. Invasive fungal infections are an important problem in the treatment of patients with hematological malignancies, and they are associated with significant morbidity and mortality. The diagnosis of invasive clinical infections in these patients is complex, and the treatment, which must occur as early as possible, is difficult. There are several studies that have shown a possible link between iron overload and an increased susceptibility to infections. This link is also relevant for patients with hematological malignancies and for those treated with allogeneic hematopoietic stem cell transplantation. The role of iron and its metabolism in the virulence and pathogenesis of various invasive fungal infections is intriguing, and so far, there is some evidence linking invasive fungal infections to iron or iron overload. Clarifying the possible association of iron and iron overload with susceptibility to invasive fungal infections could be important for a better prevention and treatment of these infections in patients with hematological malignancies.
  • 3.8K
  • 11 Aug 2022
Topic Review
Phytoplankton
Phytoplankton (/ˌfaɪtoʊˈplæŋktən/) are the autotrophic (self-feeding) components of the plankton community and a key part of oceans, seas and freshwater basin ecosystems. The name comes from the Greek words φυτόν (phyton), meaning "plant", and πλαγκτός (planktos), meaning "wanderer" or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye. However, when present in high enough numbers, some varieties may be noticeable as colored patches on the water surface due to the presence of chlorophyll within their cells and accessory pigments (such as phycobiliproteins or xanthophylls) in some species. About 1% of the global biomass is due to phytoplankton.
  • 3.8K
  • 10 Oct 2022
Topic Review
Fragment Identifier
In computer hypertext, a fragment identifier is a string of characters that refers to a resource that is subordinate to another, primary resource. The primary resource is identified by a Uniform Resource Identifier (URI), and the fragment identifier points to the subordinate resource. The fragment identifier introduced by a hash mark # is the optional last part of a URL for a document. It is typically used to identify a portion of that document. The generic syntax is specified in RFC 3986. The hash-mark separator in URIs is not part of the fragment identifier.
  • 3.8K
  • 30 Nov 2022
Topic Review
Cerium Nitrate
Cerium nitrate refers to a family of nitrates of cerium in the three or four oxidation state. Often these compounds contain water, hydroxide, or hydronium ions in addition to cerium and nitrate. Double nitrates of cerium also exist.
  • 3.8K
  • 27 Sep 2022
Topic Review
DC-BUS
DC-BUS is technology for reliable and economical communication over noisy DC or AC power lines. The DC-BUS was originally developed by Yamar Electronics Ltd. together with the DC-BUS Alliance, for low cost sub-networks in vehicles, using the battery lines for in-vehicle data communication. The DC-BUS converts the digital input data into phase modulated signals, protected against errors generated by noise over the powerline. On the receiving side, the received signal is demodulated into the original digital data. Gradually it became a popular means of communication in a plurality of applications within aerospace, automotive, solar energy management and lighting. It is also used as an alternative to RS-232 and RS-485 networks in some cases. The common goal for all these applications is reducing wires, saving space, lowering cost and increasing reliability.
  • 3.8K
  • 22 Nov 2022
Topic Review
Woke
Woke (/ˈwoʊk/) as a political term of African American origin refers to a perceived awareness of issues concerning social justice and racial justice. It is derived from the African-American Vernacular English expression "stay woke", whose grammatical aspect refers to a continuing awareness of these issues. By the late 2010s, woke had been adopted as a more generic slang term broadly associated with left-wing politics, socially liberal causes, feminism, LGBT activism, and cultural issues (with the terms woke culture and woke politics also being used). It has been the subject of memes, ironic usage and criticism. Its widespread use since 2014 is a result of the Black Lives Matter movement.
  • 3.8K
  • 23 Nov 2022
Topic Review
Introduction of Campus Microgrids
Campus Microgrids are a scattered group of power sources and electrical loads that are usually synchronous with the primary grid, called the utility grid. The multiple uncertainties in a microgrid, such as limited photovoltaic generations, ups and downs in the market price, and controlling different loads, are challenging points in managing campus energy with multiple microgrid systems and are a hot topic of research in the current era. Microgrids deployed at multiple campuses can be successfully operated with an exemplary energy management system (EMS) to address these challenges, offering several solutions to minimize the greenhouse gas (GHG) emissions, maintenance costs, and peak load demands of the microgrid infrastructure. 
  • 3.8K
  • 11 Nov 2021
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