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Topic Review
Structural Change in Agriculture
It is common sense that it needs social and economic perspectives to understand structural changes in agriculture. The current study asserts that, likewise, the integration of the farm level (micro), the sectoral level (meso), and the societal level (macro) are needed to gain insight into the system of agricultural structures.
  • 2.3K
  • 13 Jul 2021
Topic Review
Cooperative Learning and Social Learning
Cooperative Learning (CL) has been seen as a student-centered model (SCM) capable of promoting students’ active engagement and improvement. The model has five elements: positive interdependence, appropriate social skills, promotive face-to-face interaction, individual accountability, and group processing, which have been identified as critical and are widely described in the literature. Namely, in Physical Education (PE), CL has been important in the four learning domains, i.e., physical, cognitive, social, and affective. Particularly, from CL, students can improve their ability to listen to others, construct understanding together, and respect, encourage, and support each other to learn.
  • 2.3K
  • 10 Aug 2021
Topic Review
Leader—Member Exchange (LMX) Theory
The LMX theory was first described as “Vertical Dyad Linkage” (VDL). Graen and Uhl-Bien (1995) argued that the LMX theory consists of four stages, wherein each stage is related to and builds upon the previous stages. Leader–member exchange (LMX) theorists argue that leaders in the organization should give more responsibility to their followers, delegate powers, support the sharing of work-related knowledge, and allow participation in decision-making processes. LMX theory is a psychological process variable and plays an intermediary role between transformational leadership and knowledge management. 
  • 2.3K
  • 16 Sep 2021
Topic Review
A Rule-Based Grapheme-to-Phoneme Conversion System
Natural language processing often requires grapheme-to-phoneme (G2P) conversion of an orthographic text. G2P converts strings of graphemes to corresponding sequences of phonetic transcription characters, directly from orthographic representations and it is crucial for many applications in various areas of speech and language processing.
  • 2.3K
  • 25 Mar 2022
Topic Review
Fungal Enzymes Involved in Plastics Biodegradation
Plastic pollution is a growing environmental problem, in part due to the extremely stable and durable nature of this polymer. As recycling does not provide a complete solution, research has been focusing on alternative ways of degrading plastic. Fungi provide a wide array of enzymes specialized in the degradation of recalcitrant substances and are very promising candidates in the field of plastic degradation.
  • 2.3K
  • 08 Jul 2022
Topic Review
Phosphorus-Substituted Pyridines
Phosphorus(V)-substituted pyridine was first synthesized by Plazek’s research group in 1936 by a reaction of 2-dimethylaminopyridine with phosphorus trichloride under oxidative conditions. Later, related compounds were obtained by reactions of metalated pyridines with phosphorus-halogen compounds, of pyridinediazonium tetrafluoroborate with phosphorus trichloride, of N-alkoxypyridines with sodium diethyl phosphite and phosphines, and of N-pyridylpyridines with phosphonic acid, by the Michaelis–Arbuzov reaction, Pd(II)-catalyzed phosphorylation of halopyridines, cyclization of phosphorus-containing 3-azatrienes, and the Diels–Alder reaction involving 3-phosphoryl-1-azadienes.
  • 2.3K
  • 20 Mar 2023
Topic Review
The Mexican Ecological Conscience
The number of Mexicans who buy sustainable products has been increasing, which has led to sustainable trade. According to Vargas-Hernández and Cervantes-Guzmán (2019), “eco-conscious” consumers are a fast-growing niche in Mexico; moreover, there is also some research on green products in Mexican academia, such as the TNS Research Green Study (2010), which notes that almost 50% of Mexicans are more willing to buy green products, so further research on Mexican consumers and their sustainability intentions is needed. 
  • 2.3K
  • 15 Jun 2022
Topic Review
Unsupervised Keyphrase Extraction
A review of unsupervised keyphrase extraction methods.
  • 2.3K
  • 21 Feb 2021
Topic Review
Natural Products from Madagascar
Natural products with biological activity represent a primary source of commodities ranging from human nutrition to therapy. Also they may represent cosmetic principles and/or recreational tools. These natural means have been used by mankind for centuries, if not millennia. They are commonly used all over the world in socio-economical contexts, but are particularly attractive in disadvantaged areas or economically emerging situations all over the world because of their accessibility and low cost/use ratio.
  • 2.3K
  • 08 Oct 2021
Topic Review
The Medicinal Properties for FDA-Approved Oximes
Organophosphate (OP) poisoning continues to be a major threat to humans. Oximes represent the most important class in medicinal chemistry, renowned for their widespread applications as OP antidotes, drugs and intermediates for the synthesis of several pharmacological derivatives. Common oxime based reactivators or nerve antidotes include pralidoxime, obidoxime, HI-6, trimedoxime and methoxime, among which pralidoxime is the only FDA-approved drug. Cephalosporins are β-lactam based antibiotics and serve as widely acclaimed tools in fighting bacterial infections. Oxime based cephalosporins have emerged as an important class of drugs with improved efficacy and a broad spectrum of anti-microbial activity against Gram-positive and Gram-negative pathogens.
  • 2.3K
  • 21 Jan 2022
Topic Review
Photocathode Materials
Photoelectrochemical water splitting is a promising approach to sustainable hydrogen production with no carbon emissions. Hydrogen being a future fuel to coming human generations is of utmost importance. The photocathodes in a photoelectrochemical (PEC) water-splitting cell are essential for the direct evolution of hydrogen. Among the known photocathodes, Cu-based p-type semiconducting materials are the most promising photo-absorber materials owing to their low-cost, low toxicity, natural abundance, suitable band-gaps, and favorable band edges for reduction. 
  • 2.3K
  • 08 Nov 2022
Topic Review
Urinary Incontinence
Urinary incontinence (UI), also known as involuntary urination, is any uncontrolled leakage of urine. It is a common and distressing problem, which may have a large impact on quality of life. It has been identified as an important issue in geriatric health care. The term enuresis is often used to refer to urinary incontinence primarily in children, such as nocturnal enuresis (bed wetting). UI is an example of a stigmatized medical condition, which creates barriers to successful management and makes the problem worse. People may be too embarrassed to seek medical help, and attempt to self-manage the symptom in secrecy from others. Pelvic surgery, pregnancy, childbirth, and menopause are major risk factors. Urinary incontinence is often a result of an underlying medical condition but is under-reported to medical practitioners. There are four main types of incontinence: Treatments include pelvic floor muscle training, bladder training, surgery, and electrical stimulation. Behavioral therapy generally works better than medication for stress and urge incontinence. The benefit of medications is small and long term safety is unclear. Urinary incontinence is more common in older women.
  • 2.3K
  • 18 Nov 2022
Topic Review
Wireless Power Transfer Systems for Charging Portable Electronics
High-frequency operation of wireless power transfer (WPT) systems leads to miniaturization of the components and a higher efficiency. For this reason, various soft-switched topologies such as Class D, E, EF, etc., are used to operate the WPT systems at high frequencies in the megahertz range. Wide band gap (WBG)  and ultra-WBG devices can be used for very high frequency operation. Compensation topologies reduce the VA rating of the transmitter and can also infer voltage source or constant source characteristics to the inverters. Constant current source inverters are particularly useful when using multiple receivers since they ensure decoupled power transfer to the receivers.
  • 2.3K
  • 15 May 2023
Topic Review
Spent Mushroom Substrate for Enhanced Agricultural Sustainability
As the mushroom industry advances, it yields a consequential by-product known as spent mushroom substrate (SMS). Comprising residual fungal mycelium, lignocellulosic biomass, and enzymes, SMS has garnered significant attention as a substantial waste product.
  • 2.3K
  • 13 Oct 2023
Topic Review
Circadian Rhythms of the Hypothalamus
The nearly ubiquitous expression of endogenous 24 h oscillations known as circadian rhythms regulate the timing of physiological functions in the body. These intrinsic rhythms are sensitive to external cues, known as zeitgebers, which entrain the internal biological processes to the daily environmental changes in light, temperature, and food availability. Light directly entrains the master clock, the suprachiasmatic nucleus (SCN) which lies in the hypothalamus of the brain and is responsible for synchronizing internal rhythms. However, recent evidence underscores the importance of other hypothalamic nuclei in regulating several essential rhythmic biological functions. These extra-SCN hypothalamic nuclei also express circadian rhythms, suggesting distinct regions that oscillate either semi-autonomously or independent of SCN innervation. Concurrently, the extra-SCN hypothalamic nuclei are also sensitized to fluctuations in nutrient and hormonal signals. Thus, food intake acts as another powerful entrainer for the hypothalamic oscillators’ mediation of energy homeostasis. Ablation studies and genetic mouse models with perturbed extra-SCN hypothalamic nuclei function reveal their critical downstream involvement in an array of functions including metabolism, thermogenesis, food consumption, thirst, mood and sleep. Large epidemiological studies of individuals whose internal circadian cycle is chronically disrupted reveal that disruption of our internal clock is associated with an increased risk of obesity and several neurological diseases and disorders.
  • 2.3K
  • 10 Mar 2021
Topic Review
Old Quantum Theory
The old quantum theory is a collection of results from the years 1900–1925 which predate modern quantum mechanics. The theory was never complete or self-consistent, but was rather a set of heuristic corrections to classical mechanics. The theory is now understood as the semi-classical approximation to modern quantum mechanics. The main and final accomplishments of the old quantum theory were the determination of the modern form of the periodic table by Edmund Stoner and the Pauli Exclusion Principle which were both premised on the Arnold Sommerfeld enhancements to the Bohr model of the atom. The main tool of the old quantum theory was the Bohr–Sommerfeld quantization condition, a procedure for selecting out certain states of a classical system as allowed states: the system can then only exist in one of the allowed states and not in any other state.
  • 2.3K
  • 22 Nov 2022
Topic Review
Scalable Synthesis of Mesoporous TiO2
Increasing environmental concern, related to pollution and clean energy demand, have urged the development of new smart solutions profiting from nanotechnology, including the renowned nanomaterial-assisted photocatalytic degradation of pollutants. In this framework, increasing efforts are devoted to the development of TiO2-based nanomaterials with improved photocatalytic activity. A plethora of synthesis routes to obtain high quality TiO2-based nanomaterials is currently available. Nonetheless, large-scale production and the application of nanosized TiO2 is still hampered by technological issues and the high cost related to the capability to obtain TiO2 nanoparticles with high reaction yield and adequate morphological and structural control. 
  • 2.3K
  • 26 Jul 2021
Topic Review
Hydrogenosome
Hydrogenosome is a kind of membrane-bound organelle that widely exists in some evolutionarily distant protozoa and fungi, such as trichomonas, anaerobic fungi, endoamoeba and microsporidia. These microorganisms are anaerobic or microanaerobic, and they do not have mitochondria. Instead, they rely on the hydrogenosome, a kind of mitochondrion-related organelles (MROs), to metabolize organic matter under anoxic conditions, producing ATP to maintain their metabolism and growth.
  • 2.3K
  • 06 Apr 2022
Topic Review
Anticancer Effects of Royal Jelly
Royal jelly (RJ) is produced by the hypopharyngeal and mandibular salivary glands of young nurse honeybees. RJ contains bioactive substances, such as carbohydrates, protein, lipids, peptides, mineral salts and polyphenols which contribute to the appreciated biological and pharmacological activities. Antioxidant, anticancer, anti-inflammatory, antidiabetic, and antibacterial impacts are among the well-recognized benefits. The combination of RJ or its constituents with anticancer drugs has synergistic effects on cancer disorders, enhancing the drug’s effectiveness or reducing its side effects. 
  • 2.3K
  • 18 Oct 2022
Topic Review
Conventional PCI
Conventional PCI, often shortened to PCI, is a local computer bus for attaching hardware devices in a computer. PCI is an abbreviation for Peripheral Component Interconnect and is part of the PCI Local Bus standard. The PCI bus supports the functions found on a processor bus but in a standardized format that is independent of any particular processor's native bus. Devices connected to the PCI bus appear to a bus master to be connected directly to its own bus and are assigned addresses in the processor's address space. It is a parallel bus, synchronous to a single bus clock. Attached devices can take either the form of an integrated circuit fitted onto the motherboard itself (called a planar device in the PCI specification) or an expansion card that fits into a slot. The PCI Local Bus was first implemented in IBM PC compatibles, where it displaced the combination of several slow ISA slots and one fast VESA Local Bus slot as the bus configuration. It has subsequently been adopted for other computer types. Typical PCI cards used in PCs include: network cards, sound cards, modems, extra ports such as USB or serial, TV tuner cards and disk controllers. PCI video cards replaced ISA and VESA cards until growing bandwidth requirements outgrew the capabilities of PCI. The preferred interface for video cards then became AGP, itself a superset of PCI, before giving way to PCI Express. The first version of PCI found in retail desktop computers was a 32-bit bus using a 33 MHz bus clock and 5 V signalling, although the PCI 1.0 standard provided for a 64-bit variant as well. These have one locating notch in the card. Version 2.0 of the PCI standard introduced 3.3 V slots, physically distinguished by a flipped physical connector to prevent accidental insertion of 5 V cards. Universal cards, which can operate on either voltage, have two notches. Version 2.1 of the PCI standard introduced optional 66 MHz operation. A server-oriented variant of PCI, called PCI-X (PCI Extended) operated at frequencies up to 133 MHz for PCI-X 1.0 and up to 533 MHz for PCI-X 2.0. An internal connector for laptop cards, called Mini PCI, was introduced in version 2.2 of the PCI specification. The PCI bus was also adopted for an external laptop connector standard – the CardBus. The first PCI specification was developed by Intel, but subsequent development of the standard became the responsibility of the PCI Special Interest Group (PCI-SIG). Conventional PCI and PCI-X are sometimes called Parallel PCI in order to distinguish them technologically from their more recent successor PCI Express, which adopted a serial, lane-based architecture. PCI's heyday in the desktop computer market was approximately 1995–2005. PCI and PCI-X have become obsolete for most purposes; however, they are still common on modern desktops for the purposes of backwards compatibility and the low relative cost to produce. Many kinds of devices previously available on PCI expansion cards are now commonly integrated onto motherboards or available in USB and PCI Express versions.
  • 2.3K
  • 27 Oct 2022
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