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Topic Review
Eye Involvement in Wilson’s Disease
Wilson’s disease (WD) is an autosomal recessive genetic disorder due to a mutation of the ATP7B gene, resulting in impaired hepatic copper excretion and accumulation in various tissues. Ocular findings are one of the hallmarks of the disease. Many ophthalmological manifestations have been described and new techniques are currently available to improve their diagnosis and to follow their evolution. The most common ocular findings seen in WD patients are Kayser–Fleischer ring (KFR) and sunflower cataracts. Other ocular manifestations may involve retinal tissue, visual systems and eye mobility. Diagnosis and follow-up under decoppering treatment of these ocular findings are generally easily performed with slit-lamp examination (SLE). However, new techniques are available for the precocious detection of ocular findings due to WD and may be of great value for non-experimented ophthalmologists and non-ophthalmologists practitioners. 
  • 2.7K
  • 18 Aug 2022
Topic Review
Cryptographically-Secure Pseudorandom Number Generator
A cryptographically secure pseudorandom number generator (CSPRNG) or cryptographic pseudorandom number generator (CPRNG) is a pseudorandom number generator (PRNG) with properties that make it suitable for use in cryptography. It is also loosely known as a cryptographic random number generator (CRNG) (see Random number generation § "True" vs. pseudo-random numbers). Most cryptographic applications require random numbers, for example: key generation nonces salts in certain signature schemes, including ECDSA, RSASSA-PSS The "quality" of the randomness required for these applications varies. For example, creating a nonce in some protocols needs only uniqueness. On the other hand, the generation of a master key requires a higher quality, such as more entropy. And in the case of one-time pads, the information-theoretic guarantee of perfect secrecy only holds if the key material comes from a true random source with high entropy, and thus any kind of pseudorandom number generator is insufficient. Ideally, the generation of random numbers in CSPRNGs uses entropy obtained from a high-quality source, generally the operating system's randomness API. However, unexpected correlations have been found in several such ostensibly independent processes. From an information-theoretic point of view, the amount of randomness, the entropy that can be generated, is equal to the entropy provided by the system. But sometimes, in practical situations, more random numbers are needed than there is entropy available. Also, the processes to extract randomness from a running system are slow in actual practice. In such instances, a CSPRNG can sometimes be used. A CSPRNG can "stretch" the available entropy over more bits.
  • 2.7K
  • 20 Oct 2022
Topic Review
Functional Properties of LSM and LSCF Air Electrodes
An analysis of the literature data on the electrical, thermal, mechanical, and electrochemical properties of the conventional perovskite-type cathode materials shows that lanthanum strontium manganite (La,Sr)MnO3 (LSM) fulfils all the requirements for its use in high-temperature SOFCs. However, as the temperature decreases, the use of LSM materials, which are predominantly electronic conductors with a low level of ionic conductivity, becomes unsatisfactory due to their low electrochemical activity for the oxygen reduction reaction (ORR). On the other hand, cobalt-based perovskite materials, including lanthanum strontium cobaltite ferrite (La,Sr)(Co,Fe)O3−δ (LSCF), are characterized by superior catalytic activity due to high values of both electronic and ionic conductivity.
  • 2.7K
  • 24 Jul 2023
Topic Review
Multiple Sclerosis Pathogenesis
Multiple sclerosis (MS) is predominantly an immune-mediated disease of the central nervous system (CNS) of unknown etiology with a possible genetic predisposition and effect of certain environmental factors. It is generally accepted that the disease begins with an autoimmune inflammatory reaction targeting oligodendrocytes followed by a rapid depletion of their regenerative capacity with subsequent permanent neurodegenerative changes and disability.
  • 2.7K
  • 13 Oct 2023
Topic Review
SLMed Magnesium Alloys
The selective laser melting（SLM） technology has the characteristics of rapid solidification.Therefore, refined microstructures and high-performance products can be obtained.The microstructure of magnesium alloy varies with the cooling rate(processing).And the higher the cooling rate, the finer the microstructure of the magnesium alloy.Different cooling rates also affect the phase composition of magnesium alloys. The SLM process inhibits the formation of the second phase in the magnesium alloy due to the characteristics of rapid solidification.Post-treatment processes, such as heat treatment and hot isostatic pressing（HIP）, can be applied to SLMed magnesium alloys. These processes help to close the pores , dissolve the second phase and reduce the source of cracks caused by the mismatch between the second phase and the α-Mg matrix, thereby improving the  mechanical properties of the magnesium alloy, especially the elongation.However, SLMed magnesium alloys need further research in the application of post-processing, alloy design, base material purification, and thermodynamic and kinetic theoretical calculations of intermetallic compounds.
  • 2.7K
  • 19 Aug 2020
Topic Review
Social Physique Anxiety Scale
Social physique anxiety (SPA) is the anxiety experienced when a person believes they are being observed or judged on their appearance; it is considered to be a subtype of social anxiety.
  • 2.7K
  • 21 Oct 2021
Topic Review
Hotel Food and Beverage Department Engagement with Sustainability
In the hospitality sector, particularly in the food and beverage department, pollution and consumption of scarce resources remain issues. The hotel industry has increasingly recognized the importance of addressing sustainability issues, particularly in the food and beverage (F&B) department. However, while environmental problems remain pressing, sustainability is a complex concept that is often subject to varying interpretations and lacks a clear, consistent definition.
  • 2.7K
  • 29 Jun 2023
Topic Review
Methods for Reducing Water Absorption of Composite Materials
Plant fiber reinforced polymer matrix composites have attracted much attention in many industries due to their abundant resources, low cost, biodegradability, and lightweight properties. Compared with synthetic fibers, various plant fibers are easy to obtain and have different characteristics, making them a substitute for synthetic fiber composite materials. In order to address the adverse effects of natural fiber moisture absorption on the mechanical properties and dimensional stability of composite materials, researchers have modified fibers through various chemical and physical methods. The various methods to reduce the water absorption of composite materials such as fiber surface chemical treatment, the use of compatibilizers, fiber mixing, nanofillers, and polymer coatings.
  • 2.7K
  • 27 Oct 2023
Topic Review
Texture (Crystalline)
In materials science, texture is the distribution of crystallographic orientations of a polycrystalline sample (it is also part of the geological fabric). A sample in which these orientations are fully random is said to have no distinct texture. If the crystallographic orientations are not random, but have some preferred orientation, then the sample has a weak, moderate or strong texture. The degree is dependent on the percentage of crystals having the preferred orientation. Texture is seen in almost all engineered materials, and can have a great influence on materials properties. Also, geologic rocks show texture due to their thermo-mechanic history of formation processes. One extreme case is a complete lack of texture: a solid with perfectly random crystallite orientation will have isotropic properties at length scales sufficiently larger than the size of the crystallites. The opposite extreme is a perfect single crystal, which likely has anisotropic properties by geometric necessity.
  • 2.7K
  • 04 Nov 2022
Topic Review
Beetroot, A Remarkable Vegetable
The cardioprotective effects of dietary nitrate from beetroot in healthy and hypertensive individuals are undeniable and irrefutable. Nitrate and nitrate-derived nitrite are precursors for nitric oxide synthesis, which promotes positive effects on cardiomyocytes and myocardial ischemia/reperfusion, improving endothelial function, reducing arterial stiffness and stimulating smooth muscle relaxation, consequently decreasing systolic and diastolic blood pressures.
  • 2.7K
  • 24 Oct 2020
Topic Review
Echinacea purpurea (L.) Moench
Echinacea purpurea (L.) Moench (EP)is a perennial herbaceous flowering plant, commonly known as purple coneflower and it belongs to the Asteraceae family. The Echinacea genus is originally from North America, in the United States, and its species are widely distributed throughout. There are nine different species of Echinacea, but only three of them are used as medicinal plants with wide therapeutic uses: Echinacea purpurea (L.) Moench, Echinacea pallida (Nutt.) Nutt. and Echinacea angustifolia DC. Several significant groups of bioactive compounds with pharmacological activities have been isolated from Echinacea species. Numerous beneficial effects have been demonstrated about these compounds.
  • 2.7K
  • 20 May 2022
Topic Review
Human Embryonic Heart Start Beating
The onset of embryonic heart beating may be regarded as the defining feature for the beginning of personal human life. Clarifying the timing of the first human heartbeat, therefore, has religious, philosophical, ethical, and medicolegal implications.
  • 2.7K
  • 20 Jun 2022
Topic Review
Embryonic Retina Self-Organization In Vivo
Self-organization is a process that ensures histogenesis of the eye retina. The phenomenon of self-organisation is discussed in the spatiotemporal context and illustrated by key findings during vertebrate retina development in vivo and retinal regeneration in amphibians in situ. Described also are histotypic 3D structures obtained from the disaggregated retinal progenitor cells of birds and retinal 3D organoids derived from the mouse and human pluripotent stem cells.
  • 2.7K
  • 30 Jun 2022
Topic Review
Green Synthesis of Zinc Oxide Nanoparticles
Zinc oxide nanoparticles (ZnO NPs) can be used effectively and efficiently for water treatment, along with other nanotechnologies. Owing to rising concerns regarding the environmental unfriendliness and toxicity of nanomaterials, ZnO NPs have been synthesized through biologically available and replenishable sources using a green chemistry or green synthesis protocol. The green-synthesized ZnO NPs are less toxic, more eco-friendly, and more biocompatible than other chemically and physically synthesized materials.
  • 2.7K
  • 13 Dec 2022
Topic Review
Telework, Remote Work and Hybrid Work
Employees’ work environment has drastically shifted from offices to homes. Telework is often a desired employee benefit, but employers consider it a temporary setting. The lasting COVID-19 pandemic has changed the concept of telework. Home office has gained importance and will likely become an essential part of the working environment even after the pandemic.
  • 2.7K
  • 25 Jun 2023
Topic Review
Ignition of Fires from Electrical Causes
In a number of countries, somewhere around 20% of reported building fires are due to electrical faults or failures. There can be a number of mechanisms responsible, but arcing in air and hot-surface ignitions of combustible materials are important causes. Details of these two mechanisms are reviewed. It is shown that even though arcing in air produces temperatures greatly higher than the ignition temperature of any ignitable solid, this does not always result in ignition. With regards to ignitions from hot surfaces or objects, it is shown that the area of the hot object presented to the ignitable material is a crucial variable.
  • 2.7K
  • 10 Aug 2023
Topic Review
Householder (Buddhism)
In English translations of Buddhist texts, householder denotes a variety of terms. Most broadly, it refers to any layperson, and most narrowly, to a wealthy and prestigious familial patriarch. In contemporary Buddhist communities, householder is often used synonymously with laity, or non-monastics. The Buddhist notion of householder is often contrasted with that of wandering ascetics (Pali: Pāḷi: samaṇa; Sanskrit: śramaṇa) and monastics (bhikkhu and bhikkhuni), who would not live (for extended periods) in a normal house and who would pursue freedom from attachments to houses and families. Upāsakas and upāsikās, also called śrāvakas and śrāvikās - are householders and other laypersons who take refuge in the Three Jewels (the Buddha, the teachings and the community) and practice the Five Precepts. In southeast Asian communities, lay disciples also give alms to monks on their daily rounds and observe weekly uposatha days. In Buddhist thought, the cultivation of ethical conduct and dāna or "almsgiving" will themselves refine consciousness to such a level that rebirth in one of the lower heavens is likely even if there is no further "Noble" Buddhist practice (connected with the Supramundane goal of Nibbana, "Unbinding"). This level of attainment is viewed as a proper aim for laypersons. In some traditional Buddhist societies, such as in Myanmar and Thailand, people transition between householder and monk and back to householder with regularity and celebration as in the practice of shinbyu among the Bamar people. One of the evolving features of Buddhism in the West is the increasing dissolution of the traditional distinction between monastics and laity.
  • 2.7K
  • 14 Oct 2022
Topic Review
Stereoselective Synthesis of Chiral Molecules
Metal/lipase-combo catalyzed dynamic kinetic resolution (DKR) of racemic chiral alcohols is a general and practical process to obtain the corresponding enantiopure esters R with quantitative conversion. The use of known Ru-catalysts as well as newly developed homogeneous and heterogeneous metal catalysts (Fe, V) contributed to make the DKR process more sustainable and to expand the substrate scope of the reaction. In addition to classical substrates, challenging allylic alcohols, tertiary alcohols, C1-and C2-symmetric biaryl diols turned out to be competent substrates. Synthetic utility further emerged from the integration of this methodology into cascade reactions leading to linear/cyclic chiral molecules with high ee through the formation of multiple bonds, in a one-pot procedure. 
  • 2.7K
  • 08 Oct 2021
Topic Review
Phthalocyanine Blue BN
Phthalocyanine Blue BN, also called by many names (EINECS 205-685-1), is a bright, crystalline, synthetic blue pigment from the group of phthalocyanine dyes. Its brilliant blue is frequently used in paints and dyes. It is highly valued for its superior properties such as light fastness, tinting strength, covering power and resistance to the effects of alkalis and acids. It has the appearance of a blue powder, insoluble in most solvents including water.
  • 2.7K
  • 01 Dec 2022
Topic Review
Recrystallization
In chemistry, recrystallization is a technique used to purify chemicals. By dissolving both impurities and a compound in an appropriate solvent, either the desired compound or impurities can be removed from the solution, leaving the other behind. It is named for the crystals often formed when the compound precipitates out. Alternatively, recrystallization can refer to the natural growth of larger ice crystals at the expense of smaller ones.
  • 2.7K
  • 14 Oct 2022
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