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Topic Review
Doping (Semiconductor)
In semiconductor production, doping is the intentional introduction of impurities into an intrinsic semiconductor for the purpose of modulating its electrical and optical and structural properties. The doped material is referred to as an extrinsic semiconductor. A semiconductor doped to such high levels that it acts more like a conductor than a semiconductor is referred to as a degenerate semiconductor. In the context of phosphors and scintillators, doping is better known as activation. Doping is also used to control the color in some pigments.
  • 3.2K
  • 08 Nov 2022
Topic Review
Cathinones Mexedrone, α-PVP and α-PHP
Mexedrone, α-PVP and α-PHP are synthetic cathinones. They can be considered amphetamine-like substances with a stimulating effect. Actually, studies showing their impact on DNA are totally absent. 
  • 3.2K
  • 05 Jul 2021
Topic Review
Nazirite
In the Hebrew Bible, a nazirite or nazarite is one who voluntarily took a vow described in Numbers 6:1–21. "Nazarite" comes from the Hebrew word נזיר nazir meaning "consecrated" or "separated". This vow required the person to: After following these requirements for a designated interval (which would be specified in the individual's vow), the person would immerse in a mikveh and make three offerings: a lamb as a burnt offering (olah), a ewe as a sin-offering (hatat), and a ram as a peace offering (shelamim), in addition to a basket of unleavened bread, grain offerings and drink offerings, which accompanied the peace offering. They would also shave their head in the outer courtyard of the Jerusalem Temple and then place the hair on the same fire as the peace offering. (Numbers 6:18) The nazirite is described as being "holy unto YHWH" (Numbers 6:8), yet at the same time must bring a sin offering. This has led to divergent approaches to the nazirite in the Talmud, and later authorities, with some viewing the nazirite as an ideal, and others viewing him as a sinner.
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  • 27 Oct 2022
Topic Review
Autophagic Body Formation in Plants
This article is associated with the MDPI International Journal of Molecular Sciences article, which belongs to a Special Issue Plant Cell and Organism Development, “Completing Autophagy: Formation and Degradation of the Autophagic Body and Metabolite Salvage in Plants” by Szymon Stefaniak1, Łukasz Wojtyla1, Małgorzata Pietrowska-Borek2, Sławomir Borek1,* The article has been published on https://doi.org/10.3390/ijms21062205, Int. J. Mol. Sci. 2020, 21(6), 2205. The work was financed by the National Science Centre, Poland (grant no. 2016/23/B/NZ3/00735).
  • 3.2K
  • 29 Oct 2020
Topic Review
IoT Wearable Sensors
 Interconnected sensing technology, such as IoT wearables and devices, present a promising solution for objective, reliable, and remote monitoring, assessment, and support through ambient assisted living.
  • 3.2K
  • 13 Apr 2021
Topic Review
Finale
Finale is the flagship program of a series of proprietary music notation software developed and released by MakeMusic for the Microsoft Windows and macOS operating systems. First released in 1988, version 26 was released in 2018. Finale has been regarded as one of the industry standards for music notation software. Finale is one of a number of types of software used by composers, songwriters and arrangers for creating sheet music, including the score for an entire ensemble (e.g., orchestra, concert band, big band, etc.) and parts for the individual musicians. A scorewriter is to music notation what a word processor is to text, in that they both allow fast corrections (via the "undo" button), flexible editing, easy sharing of content (via the Internet or compact storage media), and production of a clean, uniform layout. In addition, most scorewriters, including Finale, are able to use software-based synthesizers to "play" the sounds of the notated music and record the music—an especially useful feature for novice composers, when no musicians are readily available, or if a composer cannot afford to hire musicians. MakeMusic also offers several less expensive versions of Finale (currently available for Microsoft Windows only), which do not contain all of the main program's features. These include PrintMusic and a freeware program, Finale Notepad, which allows only rudimentary editing. Discontinued versions include Finale Guitar, Notepad Plus, Allegro, SongWriter, and the free Finale Reader.
  • 3.2K
  • 04 Nov 2022
Topic Review
Mental Health and Well-Being amongst Graduate Students
The mental health and well-being of graduate students are of increasing concern worldwide, and though it started as an implicit recognition that students suffer poor mental health, it has expanded into an area of publicly argued concern.
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  • 05 May 2022
Topic Review
Lemniscatic Elliptic Function
In mathematics, a lemniscatic elliptic function is an elliptic function related to the arc length of a lemniscate of Bernoulli studied by Giulio Carlo de' Toschi di Fagnano in 1718. It has a square period lattice and is closely related to the Weierstrass elliptic function when the Weierstrass invariants satisfy g2 = 1 and g3 = 0. In the lemniscatic case, the minimal half period ω1 is real and equal to where Γ is the gamma function. The second smallest half period is pure imaginary and equal to iω1. In more algebraic terms, the period lattice is a real multiple of the Gaussian integers. The constants e1, e2, and e3 are given by The case g2 = a, g3 = 0 may be handled by a scaling transformation. However, this may involve complex numbers. If it is desired to remain within real numbers, there are two cases to consider: a > 0 and a < 0. The period parallelogram is either a square or a rhombus.
  • 3.2K
  • 24 Oct 2022
Topic Review
Lusterware
Lusterware or Lustreware (respectively the US and all other English spellings) is a type of pottery or porcelain with a metallic glaze that gives the effect of iridescence. It is produced by metallic oxides in an overglaze finish, which is given a second firing at a lower temperature in a "muffle kiln", or a reduction kiln, excluding oxygen. The discovery of this technique can be traced back to the 7th century A.D. when Islam emerged in the city of Mecca. Lusterware was first created for the royal courts and the technique of lusterware on ceramic was developed originally in Iraq. Some pieces were signed by their makers, this acted as an indication of the admiration towards each craftsman. Trading in the Middle East was very popular. Abbasid lusterware was very common in trade within the Islamic world; other popular trade items were textiles and various materials for building and crafting (ivory, wood, etc.). The Abbasid period served as an era of discovery especially in relation to the production of luster. The city of Baghdad, Iran and surrounding cities were located on the Silk Road which was the hub of trading during this period. There was a movement of goods generated between Iraq and China which triggered artistic emulations both ends, as well as some transfers of technologies, notably in the realm of ceramics. Lusterware traveled along the trade routes; the production of ceramic lusterware was seen in Egypt and Syria during later centuries.
  • 3.2K
  • 27 Oct 2022
Topic Review
Tropical Savanna Climate
Tropical savanna climate or tropical wet and dry climate is a type of climate that corresponds to the Köppen climate classification categories Aw (for a dry winter) and As (for a dry summer). Tropical savanna climates have monthly mean temperatures above 18 °C (64 °F) in every month of the year and typically a pronounced dry season, with the driest month having less than 60 mm (2.36 inches) of precipitation and also less than [math]\displaystyle{ 100-\left (\frac{Total\ Annual\ Precipitation\ (mm)}{25} \right) }[/math] of precipitation :200–1 This latter fact is in direct contrast to a tropical monsoon climate, whose driest month sees less than 60 mm of precipitation but has more than [math]\displaystyle{ 100-\left (\frac{Total\ Annual\ Precipitation\ (mm)}{25} \right) }[/math] of precipitation. In essence, a tropical savanna climate tends to either see less rainfall than a tropical monsoon climate or have more pronounced dry season(s). In tropical savanna climates, the dry season can become severe, and often drought conditions prevail during the course of the year. Tropical savanna climates often feature tree-studded grasslands, rather than thick jungle. It is this widespread occurrence of tall, coarse grass (called savanna) which has led to Aw and As climates often being referred to as tropical savanna. However, there is some doubt whether tropical grasslands are climatically induced. Additionally, pure savannas, without trees, are the exception rather than the rule.
  • 3.2K
  • 24 Nov 2022
Topic Review
Advancements and Challenges in Handwritten Text Recognition
Handwritten Text Recognition (HTR) involves automatically transforming a source’s handwritten text within a digital image into its machine text representation.
  • 3.2K
  • 07 Mar 2024
Topic Review Peer Reviewed
Conductive Heat Transfer in Thermal Bridges
A thermal bridge is a component of a building that is characterized by a higher thermal loss compared with its surroundings. Their accurate modeling is a key step in energy performance analysis due to the increased awareness of the importance of sustainable design. Thermal modeling in architecture and engineering is often not carried out volumetrically, thereby sacrificing accuracy for complex geometries, whereas numerical textbooks often give the finite element method in much higher generality than required, or only treat the case of uniform materials. Despite thermal modeling traditionally belonging exclusively to the engineer’s toolbox, computational and parametric design can often benefit from understanding the key steps of finite element thermal modeling, in order to inform a real-time design feedback loop. In this entry, these gaps are filled and the reader is introduced to all relevant physical and computational notions and methods necessary to understand and compute the stationary energy dissipation and thermal conductance of thermal bridges composed of materials in complex geometries. The overview is a self-contained and coherent expository, and both physically and mathematically as correct as possible, but intuitive and accessible to all audiences. Details for a typical example of an insulated I-beam thermal bridge are provided.
  • 3.2K
  • 26 May 2022
Topic Review Peer Reviewed
Understanding the Education Policymaking Process in the United States
Considering the broad implications of education policy, it is important to understand the various facets of the education policymaking process. There are different stages of the process (i.e., issue definition, policy adoption, implementation, and evaluation) which, at times, can be difficult to comprehend when considering the competing goals of education and multiple stakeholders. Understanding the process can also be difficult due to the historical and contemporary influences of power and racism at play within and outside of society’s educational landscape—especially within the United States context. The process is highlighted as an iterative one which provides room for adjustments and changes across different contexts. By navigating the complex landscape of education policymaking, one can be better equipped to understand the intricacies of policymaking and its transformative capacity.
  • 3.2K
  • 02 Jan 2024
Topic Review
Isatis tinctoria L. (Woad)
Isatis tinctoria L. (Brassicaceae), which is commonly known as woad, is a species with an ancient and well-documented history as an indigo dye and medicinal plant. Currently, I. tinctoria is utilized more often as medicinal remedy and also as a cosmetic ingredient. In 2011, I. tinctoria root was accepted in the official European phytotherapy by introducing its monograph in the European Pharmacopoeia. The biological properties of raw material have been known from Traditional Chinese Medicine (TCM). Over recent decades, I. tinctoria has been investigated both from a phytochemical and a biological point of view. The modern in vitro and in vivo scientific studies proved anti-inflammatory, anti-tumour, antimicrobial, antiviral, analgesic, and antioxidant activities. The phytochemical composition of I. tinctoria has been thoroughly investigated and the plant was proven to contain many valuable biologically active compounds, including several alkaloids, among which tryptanthrin, indirubin, indolinone, phenolic compounds, and polysaccharides as well as glucosinolates, carotenoids, volatile constituents, and fatty acids. This article provides a general botanical and ethnobotanical overview that summarizes the up-to-date knowledge on the phytochemistry and biological properties of this valuable plant in order to support its therapeutic potential. Moreover, the biotechnological studies on I. tinctoria, which mainly focused on hairy root cultures for the enhanced production of flavonoids and alkaloids as well as on the establishment of shoot cultures and micropropagation protocols, were reviewed. They provide input for future research prospects.
  • 3.2K
  • 28 Oct 2020
Topic Review
Ammi Visnaga L.
Ammi visnaga L. (Visnaga daucoides Gaertn., Family Apiaceae), also known as Khella Baldi or toothpick weed, is an annual or biennial herb indigenous to the Mediterranean region of North Africa, Asia, and Europe. Nowadays, it is used in modern medicine to treat many aliments such as renal colic and coronary insufficiency, and is used as an antioxidant, antifungal, and antibacterial, with a larvicidal effect on mosquito larvae. 
  • 3.2K
  • 05 Nov 2021
Topic Review
Leaf area index (LAI)
Leaf area index (LAI) is an important vegetation leaf structure parameter in forest and agricultural ecosystems. Remote sensing techniques can provide an effective alternative to field-based observation of LAI. Different system configurations (passive, active, and multisource sensors on different collection platforms) has been used to estimate forest and crop LAI. The ease of use of empirical models supports these as the preferred choice for forest and crop LAI estimation. In terms of scale issues, both spectral and spatial scales impact the estimation of LAI. Uncertainty coming from various sources results in reduced accuracy in estimating LAI. 
  • 3.2K
  • 26 Oct 2020
Topic Review
Police Vehicles in Belgium
Before 2001, there were several police forces in Belgium: After the reform of 2001, there are only two police forces:
  • 3.2K
  • 18 Oct 2022
Topic Review
Verneuil Process
The Verneuil process, also called flame fusion, was the first commercially successful method of manufacturing synthetic gemstones, developed in the late 1800s by the French chemist Auguste Verneuil. It is primarily used to produce the ruby, sapphire and padparadscha varieties of corundum, as well as the diamond simulants rutile and strontium titanate. The principle of the process involves melting a finely powdered substance using an oxyhydrogen flame, and crystallising the melted droplets into a boule. The process is considered to be the founding step of modern industrial crystal growth technology, and remains in wide use to this day.
  • 3.2K
  • 18 Oct 2022
Topic Review
Geiger-Marsden Experiments
The Geiger–Marsden experiments (also called the Rutherford gold foil experiment) were a landmark series of experiments by which scientists learned that every atom has a nucleus where all of its positive charge and most of its mass is concentrated. They deduced this after measuring how an alpha particle beam is scattered when it strikes a thin metal foil. The experiments were performed between 1908 and 1913 by Hans Geiger and Ernest Marsden under the direction of Ernest Rutherford at the Physical Laboratories of the University of Manchester.
  • 3.2K
  • 25 Oct 2022
Topic Review
Resonance
Resonance describes the phenomenon of increased amplitude that occurs when the frequency of an applied periodic force (or a Fourier component of it) is equal or close to a natural frequency of the system on which it acts. When an oscillating force is applied at a resonant frequency of a dynamic system, the system will oscillate at a higher amplitude than when the same force is applied at other, non-resonant frequencies. Frequencies at which the response amplitude is a relative maximum are also known as resonant frequencies or resonance frequencies of the system. Small periodic forces that are near a resonant frequency of the system have the ability to produce large amplitude oscillations in the system due to the storage of vibrational energy. Resonance phenomena occur with all types of vibrations or waves: there is mechanical resonance, Orbital resonance, acoustic resonance, electromagnetic resonance, nuclear magnetic resonance (NMR), electron spin resonance (ESR) and resonance of quantum wave functions. Resonant systems can be used to generate vibrations of a specific frequency (e.g., musical instruments), or pick out specific frequencies from a complex vibration containing many frequencies (e.g., filters). The term resonance (from Latin resonantia, 'echo', from resonare, 'resound') originated from the field of acoustics, particularly the sympathetic resonance observed in musical instruments, e.g., when one string starts to vibrate and produce sound after a different one is struck.
  • 3.2K
  • 27 Oct 2022
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