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Topic Review
Eidetic Imagery
An eidetic image is a type of vivid mental image, not necessarily derived from an actual external event or memory. It was identified in the early twentieth century as a distinct phenomenon by psychologists including E.R. Jaensch, Heinrich Klüver, Gordon Allport and Frederic Bartlett. Later, Akhter Ahsen located eidetic imagery in a structuralist context, and explored its therapeutic applications: psychotherapists sometimes encourage their clients to create and explore eidetic images as a way of coming to terms with past life events. Eidetic imagery has also been studied in relation to the creative arts.
  • 3.2K
  • 21 Oct 2022
Topic Review
Eurypterida
Eurypterids, often informally called sea scorpions, are a group of extinct arthropods that form the order Eurypterida. The earliest known eurypterids date to the Darriwilian stage of the Ordovician period 467.3 million years ago. The group is likely to have appeared first either during the Early Ordovician or Late Cambrian period. With approximately 250 species, the Eurypterida is the most diverse Paleozoic chelicerate order. Following their appearance during the Ordovician, eurypterids became major components of marine faunas during the Silurian, from which the majority of eurypterid species have been described. The Silurian genus Eurypterus accounts for more than 90% of all known eurypterid specimens. Though the group continued to diversify during the subsequent Devonian period, the eurypterids were heavily affected by the Late Devonian extinction event. They declined in numbers and diversity until becoming extinct during the Permian–Triassic extinction event (or sometime shortly before) 251.9 million years ago. Although popularly called "sea scorpions", only the earliest eurypterids were marine; many later forms lived in brackish or fresh water, and they were not true scorpions. Some studies suggest that a dual respiratory system was present, which would have allowed for short periods of time in terrestrial environments. The name Eurypterida comes from the Ancient Greek words εὐρύς (eurús), meaning 'broad' or 'wide', and πτερόν (pterón), meaning 'wing', referring to the pair of wide swimming appendages present in many members of the group. The eurypterids include the largest known arthropods ever to have lived. The largest, Jaekelopterus, reached 2.5 meters (8.2 ft) in length. Eurypterids were not uniformly large and most species were less than 20 centimeters (8 in) long; the smallest eurypterid, Alkenopterus, was only 2.03 centimeters (0.80 in) long. Eurypterid fossils have been recovered from every continent. A majority of fossils are from fossil sites in North America and Europe because the group lived primarily in the waters around and within the ancient supercontinent of Euramerica. Only a handful of eurypterid groups spread beyond the confines of Euramerica and a few genera, such as Adelophthalmus and Pterygotus, achieved a cosmopolitan distribution with fossils being found worldwide.
  • 3.2K
  • 25 Nov 2022
Topic Review
Digital Distractions in College Classrooms and Its Impact
University campuses have progressively been equipped with technology. In fact, the presence of technology on university campuses is expected to be increasingly noticeable, as many universities are undergoing digitization processes. Students use many different types of technological devices and software applications during academic activities. Any stimulus or information that diverts an individual’s attention from the main task at hand is considered a distractor. Distractors affect the human ability to concentrate and have an external (noise, movement, etc.) or internal (thoughts, feelings, etc.) origin.
  • 3.2K
  • 29 Nov 2023
Topic Review
Hydroxyurea
Hydroxyurea (HU) is a non-alkylating agent administered for the management of different types of cancer or sickle cell disease. HU has a cytostatic action, blocking cell cycle in S-phase and also inducing double-stranded breaks in DNA. HU is generally well tolerated, however its widespread use has revealed the presence of adverse events related to tissues that have a high cellular turnover.
  • 3.2K
  • 16 Feb 2021
Topic Review
Journal Micromachines
Micromachines (ISSN 2072-666X) first launched in 2010，initially published as a quarterly journal，and received 1st Impact Factor in July 2014. In 2015，Micromachines was transferred to a monthly journal. Micromachines (ISSN 2072-666X) is an international, peer-reviewed, open access journal, which provides an advanced forum for studies on micro/nano-scaled structures, materials, devices, systems as well as related micro- and nanotechnology from fundamental research to applications. The journal publishes reviews, original research articles, and communications in this field. Our aim is to encourage scientists to publish their theoretical and experimental results in as much detail as possible. Therefore, there is no restriction on the length of the papers or the number of electronic supplementary files. Full details on experiments, materials and methods must be provided for a research article so that the results can be reproduced. Micromachines is covered by the Science Citation Index Expanded (Web of Science), Ei Compendex, Scopus, and PubMed, and its 2019 impact factor is 2.523. 
  • 3.2K
  • 26 Sep 2021
Topic Review
SPAD Arrays
The SPAD is the basic unit cell of all SiPM/PDC technologies. It consists of a photodiode biased above breakdown in a metastable state awaiting to be triggered by a photoelectron or a thermally excited carrier to switch to high current.
  • 3.2K
  • 18 Mar 2021
Topic Review
Graphene in Strain Sensing Applications
Strain sensors, otherwise known as strain gauges, are fueled by various nanomaterials, among which graphene has attracted great interest in recent years, due to its unique electro-mechanical characteristics. Graphene shows not only exceptional physical properties but also has remarkable mechanical properties, such as piezoresistivity, which makes it a perfect candidate for strain sensing applications. 
  • 3.2K
  • 04 Feb 2022
Topic Review
Compounds of Aluminium
Aluminium (or aluminum) combines characteristics of pre- and post-transition metals. Since it has few available electrons for metallic bonding, like its heavier group 13 congeners, it has the characteristic physical properties of a post-transition metal, with longer-than-expected interatomic distances. Furthermore, as Al3+ is a small and highly charged cation, it is strongly polarizing and aluminium compounds tend towards covalency; this behaviour is similar to that of beryllium (Be2+), an example of a diagonal relationship. However, unlike all other post-transition metals, the underlying core under aluminium's valence shell is that of the preceding noble gas, whereas for gallium and indium it is that of the preceding noble gas plus a filled d-subshell, and for thallium and nihonium it is that of the preceding noble gas plus filled d- and f-subshells. Hence, aluminium does not suffer the effects of incomplete shielding of valence electrons by inner electrons from the nucleus that its heavier congeners do. Aluminium's electropositive behavior, high affinity for oxygen, and highly negative standard electrode potential are all more similar to those of scandium, yttrium, lanthanum, and actinium, which have ds2 configurations of three valence electrons outside a noble gas core: aluminium is the most electropositive metal in its group. Aluminium also bears minor similarities to the metalloid boron in the same group; AlX3 compounds are valence isoelectronic to BX3 compounds (they have the same valence electronic structure), and both behave as Lewis acids and readily form adducts. Additionally, one of the main motifs of boron chemistry is regular icosahedral structures, and aluminium forms an important part of many icosahedral quasicrystal alloys, including the Al–Zn–Mg class.
  • 3.2K
  • 07 Nov 2022
Topic Review
Musical Contagion
Music can contaminate us. Sometimes, listeners perceive music as expressing some emotion (say, sadness), and this elicits the same emotion in them (they feel sad). What is musical contagion? Resesarchers presents the main theories of musical contagion that crystallize around the challenge to the leading theory of emotions as experiences of values. How and why does music contaminate us? Does musical contagion elicit garden variety emotions, such as sadness, joy, and anxiety? Does music contaminate us by simply moving us? Which role does imagination play in our affective responses to music? Is musical arousal elicited by automatic mimicry? What does musical contagion teach us about emotions? Musical contagion addresses fundamental theoretical and practical issues.
  • 3.2K
  • 10 Mar 2023
Topic Review
GDM
Gestational diabetes mellitus (GDM) is a pregnancy complication first detected in the second or third trimester in women that did not show evident glucose intolerance or diabetes before gestation. 
  • 3.2K
  • 27 May 2021
Topic Review
Tracheophyta
Vascular plants (from la vasculum 'duct'), also called tracheophytes (/trəˈkiː.əˌfaɪts/) or collectively Tracheophyta (from grc τραχεῖα ἀρτηρία (trakheîa artēría) 'windpipe', and φυτά (phutá) 'plants'), form a large group of land plants (c. 300,000 accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They also have a specialized non-lignified tissue (the phloem) to conduct products of photosynthesis. Vascular plants include the clubmosses, horsetails, ferns, gymnosperms (including conifers) and angiosperms (flowering plants). Scientific names for the group include Tracheophyta,:251 Tracheobionta and Equisetopsida sensu lato. Some early land plants (the rhyniophytes) had less developed vascular tissue; the term eutracheophyte has been used for all other vascular plants, including all living ones. Historically, vascular plants were known as "higher plants," as it was believed that they were further evolved than other plants due to being more complex organisms. However, this is an antiquated remnant of the obsolete scala naturae, and the term is generally considered to be unscientific.
  • 3.2K
  • 08 Nov 2022
Topic Review
Emergency Position-Indicating Radiobeacon Station
An emergency position-indicating radiobeacon (EPIRB) is a type of emergency locator beacon, a portable battery powered radio transmitter used in emergencies to locate airplanes, vessels, and persons in distress and in need of immediate rescue. In the event of an emergency, such as the ship sinking or an airplane crash, the transmitter is activated and begins transmitting a continuous radio signal which is used by search and rescue teams to quickly locate the emergency and render aid. The signal is detected by satellites operated by an international consortium of rescue services, COSPAS-SARSAT. The basic purpose of this system is to help rescuers find survivors within the so-called "golden day" (the first 24 hours following a traumatic event) during which the majority of survivors can usually be saved. The feature distinguishing modern EPIRBs, often called GPIRBs, from other types of emergency beacon is that it contains a GPS receiver and broadcasts its position, usually accurate within 100 metres (330 ft), to facilitate location. The standard frequency of a modern EPIRB is 406 MHz. It is an internationally regulated mobile radiocommunication service that aids search and rescue operations to detect and locate distressed boats, aircraft, and people. It is distinct from a Satellite emergency position-indicating radiobeacon station. The first form of these beacons was the 121.500 MHz ELT, which was designed as an automatic locator beacon for crashed military aircraft. These beacons were first used in the 1950s by the U.S. military and were mandated for use on many types of commercial and general aviation aircraft beginning in the early 1970s. The frequency and signal format used by the ELT beacons was not designed for satellite detection, which resulted in a system with poor location detection abilities and with long delays in detection of activated beacons. The satellite detection network was built after the ELT beacons were already in general use, with the first satellite not being launched until 1982, and even then, the satellites only provided detection, with location accuracy being roughly 20 kilometres (12 mi). The technology was later expanded to cover use on vessels at sea (EPIRB), individual persons (PLB and, starting in 2016, MSLD). All have migrated from using 121.500 MHz as their primary frequency to using 406 MHz, which was designed for satellite detection and location. Since the inception of Cospas-Sarsat in 1982, distress radiobeacons have assisted in the rescue of over 28,000 people in more than 7,000 distress situations. In 2010 alone, the system provided information used to rescue 2,388 persons in 641 distress situations.
  • 3.2K
  • 27 Oct 2022
Topic Review
Chitosan in Fish Biotechnology
Chitosan is increasingly used for safe drug and nucleic acid delivery due to well-known properties such as bioadhesion, low toxicity, biodegradability and biocompatibility. Furthermore, chitosan derivatization can be easily performed to improve solubility and stability of chitosan-nucleic acid polyplexes, and enhance efficient target cell drug delivery, cell uptake, intracellular endosomal escape, unpacking and nuclear import of expression plasmids. This review focus attention on recent advances in chitosan-mediated gene delivery for fish biotechnology applications such as fish vaccination against bacterial and viral infection, control of gonadal development, and gene overexpression and silencing for overcoming metabolic limitations such as dependence on protein-rich diets and low glucose tolerance of farmed fish.
  • 3.2K
  • 27 Oct 2020
Topic Review
Industry 4.0 in Supply Chain
Industry 4.0 is better known as the fourth industrial revolution and describes a future production system’s vision. In 2011, the idea of Industry 4.0 was first given and implemented by the German government for supporting automation in manufacturing. The fourth industrial revolution (Industry 4.0) focuses on enabling automation to integrate all manufacturing industries’ systems to achieve sustainability. There are many disruptive technologies such as the Internet of things (IoT). This means that all the devices, machines, and processes in supply chains are digitally connected through an internet connection and share the real-time information of all the processes. The Internet of things (IoT) integrates different technologies such as sensors, networks, algorithms, and applications. The IoT enables businesses to improve their supply chain network and gain better productivity. Cyber–physical system (C.P.S.) is another fundamental technology of industry 4.0. C.P.S. can be implemented in many industries such as healthcare, logistics, and automobiles. From an operational view, logistics is the critical function of any business that engages the supply chain movements. A cyber-physical system allows the supply chain network to use networking, computation, and physical processes to add value in the production process to achieve competitiveness. Another concept of Industry 4.0 concerns automatic guided vehicles (A.G.V.), which are widely used by many companies.
  • 3.2K
  • 01 Sep 2021
Topic Review
Recent Advances in Pterostilbene
Pterostilbene is a natural 3,5-dimethoxy analog of resveratrol. This stilbene compound has a strong bioactivity and exists widely in Dalbergia and Vaccinium spp. Besides natural extraction, pterostilbene can be obtained by biosynthesis. Pterostilbene has become popular because of its remarkable pharmacological activities, such as anti-tumor, anti-oxidation, anti-inflammation, and neuroprotection. Pterostilbene can be rapidly absorbed and is widely distributed in tissues, but it does not seriously accumulate in the body. Pterostilbene can easily pass through the blood-brain barrier because of its low molecular weight and good liposolubility. In this review, the studies performed in the last three years on resources, synthesis, bioactivity, and pharmacokinetics of pterostilbene are summarized.
  • 3.2K
  • 19 Nov 2020
Topic Review
Taxol Biosynthetic Pathway
Taxol is one of the most effective anticancer drugs in the world that is widely used in the treatment of several cancers. The elucidation of the taxol biosynthetic pathway is the key to solve the problem of taxol supply. So far, the taxol biosynthetic pathway has been reported to require an estimated 20 steps of enzymatic reactions, and most of enzymes involved have been well characterized. In details, the source and formation of the taxane core and the process of the downstream synthetic pathway have been basically depicted, while the modification of the core taxane skeleton has not been fully reported, mainly concerning the developments from diol intermediates to 2-debenzoyltaxane. 
  • 3.2K
  • 01 Jun 2021
Topic Review
El Toro Loco (Truck)
El Toro Loco (Spanish for "The Crazy Bull") is a monster truck currently racing in the Monster Jam series. It is currently driven by Kayla Blood. Other drivers of have included Dan Rodoni, Aaron Basl, Ryan Huffaker, Joey Parnell, Chris Baker, and Nathan Weenk. It features one of the first 3-D body shells, with horns sticking out of the roof. This body was originally designed for Bulldozer, and was found a second use for El Toro Loco. As El Toro Loco has increased in popularity, it has become the primary truck for the body style.
  • 3.2K
  • 31 Oct 2022
Topic Review
3D Genome
The genome is the most functional part of a cell, and genomic contents are organized in a compact three-dimensional (3D) structure. The genome contains millions of nucleotide bases organized in its proper frame. Rapid development in genome sequencing and advanced microscopy techniques have enabled us to understand the 3D spatial organization of the genome. Chromosome capture methods using a ligation approach and the visualization tool of a 3D genome browser have facilitated detailed exploration of the genome. 
  • 3.2K
  • 04 Nov 2021
Topic Review
Basis Set
A basis set in theoretical and computational chemistry is a set of functions (called basis functions) that is used to represent the electronic wave function in the Hartree–Fock method or density-functional theory in order to turn the partial differential equations of the model into algebraic equations suitable for efficient implementation on a computer. The use of basis sets is equivalent to the use of an approximate resolution of the identity: the orbitals [math]\displaystyle{ |\psi_i\rangle }[/math] are expanded within the basis set as a linear combination of the basis functions [math]\displaystyle{ |\psi_i\rangle \approx \sum_\mu c_{\mu i} |\mu\rangle }[/math], where the expansion coefficients [math]\displaystyle{ c_{\mu i} }[/math] are given by [math]\displaystyle{ c_{\mu i} = \sum_{\nu} \langle \mu|\nu \rangle^{-1} \langle \nu |\psi_i \rangle }[/math]. The basis set can either be composed of atomic orbitals (yielding the linear combination of atomic orbitals approach), which is the usual choice within the quantum chemistry community; plane waves which are typically used within the solid state community, or real-space approaches. Several types of atomic orbitals can be used: Gaussian-type orbitals, Slater-type orbitals, or numerical atomic orbitals. Out of the three, Gaussian-type orbitals are by far the most often used, as they allow efficient implementations of Post-Hartree–Fock methods.
  • 3.2K
  • 17 Oct 2022
Topic Review
Sponge
Sponges, the members of the phylum Porifera (/pəˈrɪfərə/; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells. Sponges have unspecialized cells that can transform into other types and that often migrate between the main cell layers and the mesohyl in the process. Sponges do not have nervous, digestive or circulatory systems. Instead, most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes. Sponges were first to branch off the evolutionary tree from the last common ancestor of all animals, making them the sister group of all other animals.
  • 3.2K
  • 22 Nov 2022
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