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Topic Review
Neurodegenerative Diseases
Neurodegenerative diseases are affecting more and more people around the world. Current therapies only treat the symptoms and not the causes of the disease. However, the pathophysiology of these diseases is now better known. In the case of Alzheimer's disease and Parkinson's disease, some common mechanisms have been identified. One of the first known mechanisms is the accumulation of proteins: α-synuclein (Parkinson's disease), Tau (Alzheimer's disease) and β-amyloid (Alzheimer's disease and Parkinson's disease) proteins. Protein accumulation is related to a disruption of mitochondrial activity associated with cell death and oxidative stress. Inflammation is also another important mechanism, which is disrupted in these pathologies.
  • 3.3K
  • 15 Sep 2023
Topic Review
VC Dimension
In Vapnik–Chervonenkis theory, the VC dimension (for Vapnik–Chervonenkis dimension) is a measure of the capacity (complexity, expressive power, richness, or flexibility) of a space of functions that can be learned by a statistical classification algorithm. It is defined as the cardinality of the largest set of points that the algorithm can shatter. It was originally defined by Vladimir Vapnik and Alexey Chervonenkis. Formally, the capacity of a classification model is related to how complicated it can be. For example, consider the thresholding of a high-degree polynomial: if the polynomial evaluates above zero, that point is classified as positive, otherwise as negative. A high-degree polynomial can be wiggly, so it can fit a given set of training points well. But one can expect that the classifier will make errors on other points, because it is too wiggly. Such a polynomial has a high capacity. A much simpler alternative is to threshold a linear function. This function may not fit the training set well, because it has a low capacity. This notion of capacity is made rigorous below.
  • 3.3K
  • 04 Nov 2022
Topic Review
Radio Broadcasting
Radio broadcasting is transmission by radio waves intended to reach a wide audience. Stations can be linked in radio networks to broadcast a common radio format, either in broadcast syndication or simulcast or both. Alternatives to terrestrial radio broadcasting include cable radio, local wire television networks, satellite radio, and internet radio via streaming media on the Internet. The signal types can be either analog audio or digital audio.
  • 3.3K
  • 30 Nov 2022
Topic Review
Cynicism
Cynicism (Ancient Greek:) is a school of thought of ancient Greek philosophy as practiced by the Cynics (Ancient Greek:; Latin: Cynici). For the Cynics, the purpose of life is to live in virtue, in agreement with nature. As reasoning creatures, people can gain happiness by rigorous training and by living in a way which is natural for themselves, rejecting all conventional desires for wealth, power, and fame, and even flouting conventions openly and derisively in public. Instead, they were to lead a simple life free from all possessions. The first philosopher to outline these themes was Antisthenes, who had been a pupil of Socrates in the late 400 BC. He was followed by Diogenes, who lived in a ceramic jar on the streets of Athens. Diogenes took Cynicism to its logical extremes, and came to be seen as the archetypal Cynic philosopher. He was followed by Crates of Thebes, who gave away a large fortune so he could live a life of Cynic poverty in Athens. Cynicism gradually declined in importance after the 3rd century BC, but it experienced a revival with the rise of the Roman Empire in the 1st century. Cynics could be found begging and preaching throughout the cities of the empire, and similar ascetic and rhetorical ideas appeared in early Christianity. By the 19th century, emphasis on the negative aspects of Cynic philosophy led to the modern understanding of cynicism to mean a disposition of disbelief in the sincerity or goodness of human motives and actions.
  • 3.3K
  • 24 Oct 2022
Topic Review
Fundamental Concepts of Hydrogels
Hydrogels are three-dimensional crosslinked porous networks and can be synthesized from natural polymers, synthetic polymers, polymerizable synthetic monomers, and combination of natural and synthetic polymers. Synthesis of hydrogels involves physical, chemical and hybrid bonding. The bonding is formed via different routes such as solution casting, solution mixing, bulk polymerization, free radical mechanism, radiation method, and interpenetrating network formation. The synthesized hydrogels have significant properties such as mechanical strength, flexibility, biocompatibility, biodegradability, swellability, and stimuli sensitivity. Furthermore, owing to the smart and aqueous medium, robust mechanical strength, adhesiveness, stretchability, strain sensitivity, and self-healability, hydrogels can be potentially used in biomedical, electrochemical, sensors, contact lens, and soft robotic applications.
  • 3.3K
  • 03 Dec 2020
Topic Review
Long-Term Care Insurance Pilot in China
China launched long-term care insurance (LTCI) pilot program in 2016, there are great challenges associated with developing a sustainable LTCI system due to limited financial resources and a rapid increase in the aging population. It is needed to evaluate the impact of LTCI policy development from diverse perspectives and using various evaluation methods.
  • 3.3K
  • 20 Jun 2022
Topic Review
Gas Chromatography - Vacuum Ultraviolet Spectroscopy (GC-VUV)
Gas Chromatography - Vacuum Ultraviolet (GC-VUV) spectroscopy is a universal detection platform for gas chromatography. The first benchtop detector was introduced in 2014 with detection capabilities between 120 - 240 nm. This portion of the ultraviolet spectrum had historically been restricted to bright source synchrotron facilities due to significant background absorption challenges inherent to working within the wavelength range. Further detector platform development has extended the wavelength detection range out from 120 - 430 nm. VUV detection provides both qualitative and quantitative spectral information for most gas phase compounds. GC-VUV spectral data is three dimensional (time, absorbance, wavelength) and specific to chemical structure. Nearly all compounds absorb in the VUV region of the electromagnetic spectrum with the exception of carrier gases hydrogen, helium, and argon. The high energy, short wavelength VUV photons probe electronic transitions in almost all chemical bonds including ground state to excited state. The result is spectral "fingerprints" that are specific to individual compound structure and can be readily identified by the VUV library. Unique VUV spectra enable closely related compounds such as structural isomers to be clearly differentiated. VUV detectors complement mass spectrometry, which struggles with characterizing constitutional isomers and compounds with low mass quantitation ions. VUV spectra can also be used to deconvolve analyte co-elution, resulting in an accurate quantitative representation of individual analyte contribution to the original response. This characteristically lends itself to significantly reducing GC runtimes through flow rate-enhanced chromatographic compression. VUV spectroscopy follows the simple linear relationship between absorbance and concentration described by the Beer-Lambert Law resulting in more accurate retention time-based identification. VUV absorbance spectra also exhibit feature similarity within compound classes, meaning VUV detectors can rapidly compound class characterization in complex samples through compound spectral shape and retention index information. Advances in technology reduces the typical group analysis data processing time from 15-30 minutes to <1 minute per sample.
  • 3.3K
  • 17 Nov 2022
Topic Review
Additive Manufacturing Technology in Railway Infrastructure Systems
Additive manufacturing technologies, well known as three-dimensional printing (3DP) technologies, have been applied in many industrial fields, including aerospace, automobiles, shipbuilding, civil engineering and nuclear power. However, despite the high material utilization and the ability to rapidly construct complex shaped structures of 3D printing technologies, the application of additive manufacturing technologies in railway track infrastructure is still at the exploratory stage. 
  • 3.3K
  • 07 Jan 2022
Topic Review
Phospholipase A1
Phospholipase A1 (PLA1) is an enzyme that cleaves an ester bond at the sn-1 position of glycerophospholipids, producing a free fatty acid and a lysophospholipid.
  • 3.3K
  • 27 Apr 2022
Topic Review
Plant-Derived Exosome-like Nanoparticle as Biomolecules
Plant-derived exosome-like nanoparticles (PDENs) comprise various bioactive biomolecules. As an alternative cell-free therapeutic approach, they have the potential to deliver nano-bioactive compounds to the human body, and thus lead to various anti-inflammatory, antioxidant, and anti-tumor benefits.
  • 3.3K
  • 04 May 2023
Topic Review
Cancer (Constellation)
Cancer, recognized as one of the twelve zodiac constellations, is situated in the northern celestial hemisphere. Named after the Latin word for crab, Cancer is associated with the Greek myth of the crab sent by Hera to distract Hercules during his battle with the Hydra.
  • 3.3K
  • 29 Feb 2024
Topic Review
Ionic Liquids in Electrochemistry
The roles of room temperature ionic liquids (RTILs) and RTIL based solvent systems as proposed alternatives for conventional organic electrolyte solutions are described. Ionic liquids are introduced as well as the relevant properties for their use in electrochemistry (reduction of ohmic losses), such as diffusive molecular motion and ionic conductivity.
  • 3.3K
  • 21 Jan 2021
Topic Review
Purple Drank
Purple drank is a recreational drug, created by combining prescription-grade cough syrup with a soft drink and hard candy. The concoction originated in Houston, Texas, and is popular among those who belong to the hip hop subculture or reside in the southern United States.
  • 3.3K
  • 02 Nov 2022
Topic Review
Vitamin D Metabolism Gene Polymorphisms
Vitamin D is a potent immunonutrient that through its main metabolite calcitriol, regulates the immunomodulation of macrophages, dendritic cells, T and B lymphocytes, which express the vitamin D receptor (VDR), and they produce and respond to calcitriol. Genetic association studies have shown that up to 65% of vitamin D serum variance may be explained due to genetic background. 
  • 3.3K
  • 02 Jan 2022
Biography
George Marshall
General of the Army George Catlett Marshall Jr. (December 31, 1880 – October 16, 1959) was an American soldier and statesman. He rose through the United States Army to become Chief of Staff under presidents Franklin D. Roosevelt and Harry S. Truman, then served as Secretary of State and Secretary of Defense under Truman.[1] Winston Churchill lauded Marshall as the "organizer of victory" for hi
  • 3.3K
  • 15 Nov 2022
Topic Review
Phytoremediation
Phytoremediation is defined as the use of plant species as a means of purifying polluted soil, water, and air. The term derives from the Greek word phyto (“plant”) and the Latin word remedium (“to correct or remove an evil”). Phytoremediation is a more economically feasible and efficient remediation option than other techniques, such as washing, flushing, or solidification.
  • 3.3K
  • 13 Feb 2023
Topic Review
Molecular Characterization of XX Maleness
Androgens and anti-Müllerian hormone (AMH), secreted by the foetal testis, are responsible for the development of male reproductive organs and the regression of female anlagen. Virilization of the reproductive tract in association with the absence of Müllerian derivatives in the XX foetus implies the existence of testicular tissue, which can occur in the presence or absence of SRY. Recent advancement in the knowledge of the opposing gene cascades driving to the differentiation of the gonadal ridge into testes or ovaries during early foetal development has provided insight into the molecular explanation of XX maleness.
  • 3.3K
  • 13 Oct 2021
Topic Review
Coping Strategies and Prevention of Cyberbullying
Cyberbullying behaviours begin at primary school, so the actions taken by pre-teachers will play a key role in achieving the goals in the 2030 Agenda for Sustainable Development. More specifically, active coping strategies are essential in reducing victimisation. There is great importance of designing and implementing training programmes to prevent and/or reduce cyberbullying as part of student primary school teachers’ education. One promising way of achieving the Sustainable Development Goals in schools is to encourage pre-service teachers to use active strategies to intervene in cyberbullying and to abandon ineffective strategies in their future professional lives. It is important that pre-service teachers’ knowledge of effective coping strategies is enhanced and that any beliefs justifying cyberbullying are deconstructed.
  • 3.3K
  • 31 May 2022
Topic Review
Somatic Cell Nuclear Transfer
Somatic cell nuclear transfer (SCNT) is a technique for generating embryos with genomic information identical to that of donor cells. SCNT has presented various insights into the process of de-differentiation by cellular reprogramming.  Now authors are focusing on the challenge of understanding the potential of pluripotent stem cells and the safe use. Moreover, stem cells from livestock have provided many potential to the academic field as well as medical and industrial applications.
  • 3.3K
  • 12 May 2021
Topic Review
Graphene Oxide and Biological Properties
Desirable carbon allotropes such as graphene oxide (GO) have entered the field with several biomedical applications, owing to their exceptional physicochemical and biological features, including extreme strength, found to be 200 times stronger than steel; remarkable light weight; large surface-to-volume ratio; chemical stability; unparalleled thermal and electrical conductivity; and enhanced cell adhesion, proliferation, and differentiation properties. 
  • 3.3K
  • 11 May 2021
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