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Topic Review
Wavelet Scattering Transform
A knowledge-based feature extraction technique has been developed by Bruna and Malat named wavelet scattering transform (WST), which utilizes complex wavelets to balance the discrimination ability and stability of the time-frequency domain signal.
  • 6.8K
  • 09 Dec 2022
Topic Review
Perinatal Stem Cells
Perinatal tissues refer to tissues that are discarded at birth, such as the placenta, umbilical cord, cord blood, and amniotic fluid, and different stem and progenitor cell types can be isolated from these tissues. Regenerative medicine has found in the perinatal medical wastes one of the most promising sources of various cells and tissues for use in cell therapy and tissue engineering, both in experimental and clinical settings. The primary source of perinatal stem cells is cord blood. Cord blood has been a well-known source of hematopoietic stem/progenitor cells. Other perinatal tissues contain non-hematopoietic cells with potential therapeutic value. Indeed, in advanced perinatal cell therapy trials, mesenchymal stromal cells are the most commonly used.
  • 6.8K
  • 14 Jan 2021
Topic Review
Instability of Peptide and Possible Causes of Degradation
Peptides are different from proteins. Although both are composed of amino acids, peptides are smaller molecules comprised of two or more amino acids linked by peptide bonds, while proteins are long chains of amino acids that may have a much larger number of amino acids. Peptide stability in aqueous solutions is critical when developing parenteral formulations, as the potency of a peptide is often compromised due to chemical or physical degradation pathways.
  • 6.8K
  • 29 Mar 2023
Topic Review
Polymer 3D Printing
Polymer 3D printing is an emerging technology with recent research translating towards increased use in diverse industries. The polymer 3D printing process works by depositing a polymer in a directed fashion to form a completed part, generally through layer by layer deposition.  Polymer printing is advantageous because it enables printing low-cost functional parts with diverse properties and capabilities. An important aspect polymer 3D printing is the consideration of materials, processes, and design strategies that all influence a parts performance. Research in materials has led to the development of polymers with advantageous characteristics for mechanics and biocompatibility, with tuning of mechanical properties achieved by altering printing process parameters. Suitable polymer printing processes include extrusion, resin, and powder 3D printing, which enable directed material deposition for the design of advantageous and customized architectures.  Through careful consideration of material, process, and design it is possible to create a 3D printed polymer part of complex geometry that is tuned for a specific application on a per-print basis.
  • 6.8K
  • 23 Jun 2021
Topic Review
Anti Urination Devices in Norwich
Anti urination devices were a form of hostile architecture installed in Norwich and the surrounding area in the late 19th century to discourage public urination. The overcrowded and narrow streets of the city centre and a lack of public toilets led to men urinating against the side of buildings, but the installation of new public urinals to address the issue was delayed by disputes over where they were to be sited. Anti urination devices were built in places which suffered particular problems with public urination, and were intended to discourage men from urinating at that spot. Most were built of sloped or curved stone, flint or concrete, and were shaped such that anyone attempting to urinate against the wall would need to stand well away from the wall in public view, hopefully discouraging them from doing so. The slope of the structure meant that should anyone still attempt to urinate against it, the stream of urine would be deflected back onto their feet and legs. A few instead consisted of a spiked metal bar positioned across a corner at the height of a typical man's groin, and were intended to dissuade men from approaching the corner with their genitals exposed. Following improved public toilet provision from the 1890s onwards, the problems caused by the lack of urinals became less of an issue, and anti urination devices ceased to be installed. Although most metal examples were removed during the Second World War, and many others have been demolished in subsequent years, around 30 remain in place in central Norwich with further surviving examples in other parts of East Anglia.
  • 6.8K
  • 07 Oct 2022
Topic Review
Shotgun Wedding
A shotgun wedding is a wedding that is arranged to avoid embarrassment due to premarital sex possibly leading to an unintended pregnancy, rather than out of the desire of the participants. The phrase is a primarily American colloquialism, termed as such based on a stereotypical scenario where the father of the pregnant bride-to-be threatens the reluctant groom with a shotgun to ensure that he follows through with the wedding.
  • 6.8K
  • 25 Nov 2022
Topic Review
Human Mobility and Smart City
Human mobility, the movement of human beings in space and time, reflects the spatial-temporal characteristics of human behavior. With big data analytics, human mobility research can be used to facilitate smart city development, in multiple disciplines such as smart traffic, smart urban planning, smart health, smart safety, smart commerce, etc. A framework for linking international academic research and city-level management policy was established and applied to the case of Hong Kong. Literatures regarding human mobility research using big data are reviewed. These studies contribute to (1) discovering the spatial-temporal phenomenon, (2) identifying the difference in human behaviour or spatial attributes, (3) explaining the dynamic of mobility, and (4) applying to city management. Then, the application of the research to smart city development are scrutinised based on email queries to various governmental departments in Hong Kong. With further improvement in the practical value of data analytics and the utilization of data sourced from multiple sectors, paths to achieve smarter cities from policymaking perspectives are highlighted.
  • 6.8K
  • 06 Jun 2021
Topic Review
Emgrand EC7
The Geely Emgrand or originally, the Emgrand EC7 is a compact car produced by the Emgrand division of the Chinese automaker Geely. After the discontinuation of the "Emgrand" brand, Emgrand EC7 was renamed to Geely Emgrand in 2014. The second generation Geely Emgrand was shown to public in 2014 Beijing Auto Show.
  • 6.8K
  • 23 Nov 2022
Topic Review
Frequency
Frequency is the number of occurrences of a repeating event per unit of time. It is also referred to as temporal frequency, which emphasizes the contrast to spatial frequency and angular frequency. Frequency is measured in units of hertz (Hz) which is equal to one occurrence of a repeating event per second. The period is the duration of time of one cycle in a repeating event, so the period is the reciprocal of the frequency. For example: if a newborn baby's heart beats at a frequency of 120 times a minute (2 hertz), its period, T, — the time interval between beats—is half a second (60 seconds divided by 120 beats). Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio signals (sound), radio waves, and light.
  • 6.8K
  • 16 Nov 2022
Topic Review
Art
Art is a diverse range of human activities in creating visual, auditory or performing artifacts (artworks), expressing the author's imaginative, conceptual idea, or technical skill, intended to be appreciated for their beauty or emotional power. In their most general form these activities include the production of works of art, the criticism of art, the study of the history of art, and the aesthetic dissemination of art. Music, theatre, film, dance, and other performing arts, as well as literature and other media such as interactive media, are included in a broader definition of art or the arts. Until the 17th century, art referred to any skill or mastery and was not differentiated from crafts or sciences. In modern usage after the 17th century, where aesthetic considerations are paramount, the fine arts are separated and distinguished from acquired skills in general, such as the decorative or applied arts. Though the definition of what constitutes art is disputed and has changed over time, general descriptions mention an idea of imaginative or technical skill stemming from human agency and creation. The nature of art and related concepts, such as creativity and interpretation, are explored in a branch of philosophy known as aesthetics.
  • 6.8K
  • 07 Nov 2022
Topic Review
Tirukkuṛaḷ
The Tirukkural (திருக்குறள், literally Sacred Verses), or shortly the Kural, is a classic Tamil language text consisting of 1,330 short couplets of seven words each, or Kurals. The text is divided into three books, each with aphoristic teachings on virtue (aram, dharma), wealth (porul, artha) and love (inbam, kama). Considered one of the greatest works on ethics and morality, it is known for its universality and secular nature. Its authorship is traditionally attributed to Valluvar, also known in full as Thiruvalluvar. The text has been dated variously from 300 BCE to 5th century CE. The traditional accounts describe it as the last work of the third Sangam, but linguistic analysis suggests a later date of 450 to 500 CE and that it was composed after the Sangam period. The Kural is traditionally praised with epithets and alternate titles such as "the Tamil Veda" and "the divine book." It emphasizes non-violence and moral vegetarianism as virtues for an individual.[a] In addition, it highlights truthfulness, self-restraint, gratitude, hospitality, kindness, goodness of wife, duty, giving, and so forth, besides covering a wide range of social and political topics such as king, ministers, taxes, justice, forts, war, greatness of army and soldier's honor, death sentence for the wicked, agriculture, education, abstinence from alcohol and intoxicants. It also includes chapters on friendship, love, sexual union, and domestic life. The Kural has been widely admired by scholars and influential leaders across the ethical, social, political, economical, religious, philosophical, and spiritual spheres over its history. These include Ilango Adigal, Kambar, Leo Tolstoy, Mahatma Gandhi, Albert Schweitzer, Constantius Joseph Beschi, Karl Graul, George Uglow Pope, Alexander Piatigorsky, and Yu Hsi. The text has been translated into at least 40 Indian and non-Indian languages. The Kural is considered a masterpiece and one of the most important texts of the Tamil Literature. The Tamil people and the government of Tamil Nadu have long celebrated and upheld the text with reverence.
  • 6.8K
  • 10 Oct 2022
Topic Review
Toxicity of Titanium Compounds
Titanium and its compounds are broadly used in both industrial and domestic products, including jet engines, missiles, prostheses, implants, pigments, cosmetics, food, and photocatalysts for environmental purification and solar energy conversion. Although titanium/titania-containing materials are usually safe for human, animals and environment, increasing concerns on their negative impacts have been postulated. We have reported the state of knowledge about toxicity of titanium, its alloys and oxides. Due to the alarming increase in titania/titanium applications in various daily care products and medical treatment (e.g. dental implants) the possible toxicity and environmental impact should be considered.  The collected data might allow to identify some harms associated with using of titania and titanium compounds.
  • 6.8K
  • 21 Feb 2021
Topic Review
LOL
LOL, or lol, is an acronym for laugh(ing) out loud or lots of laughs, and a popular element of Internet slang. It was first used almost exclusively on Usenet, but has since become widespread in other forms of computer-mediated communication and even face-to-face communication. It is one of many initialisms for expressing bodily reactions, in particular laughter, as text, including initialisms for more emphatic expressions of laughter such as LMAO ("laugh(ing) my ass off") and ROFL (or its older form ROTFL; "roll(ing) on the floor laughing"). Other unrelated expansions include the now mostly obsolete "lots of luck" or "lots of love" used in letter-writing. The list of acronyms "grows by the month", and they are collected along with emoticons and smileys into folk dictionaries that are circulated informally amongst users of Usenet, IRC, and other forms of (textual) computer-mediated communication. These initialisms are controversial, and several authors recommend against their use, either in general or in specific contexts such as business communications. The Oxford English Dictionary first listed LOL in March, 2011.
  • 6.8K
  • 09 Oct 2022
Topic Review
The Subretinal Space of the Eye
The subretinal space is located between the retinal pigment epithelium (RPE) and the photoreceptive cells. The majority of the retina is a delicate matrix of photoreceptive cells and their support network which are responsible for human vision. These cells are separated from the choroid by a layer of pigment epithelium. The RPE has tight junctions, effectively insulating the inside of the retina from systemic circulation; the contents of the retina can then be controlled by transcellular transport.
  • 6.8K
  • 03 May 2025
Topic Review
Electron Transport Layer
The electron transport layer (ETL) acts as a function of collecting electrons and blocking the transport of holes to the FTO electrode in the PSC. The mesoporous structure of the ETL promotes the crystallization and film formation of perovskite and shortens the migration path of photogenerated electrons. A suitable ETL should have an energy band position that matches the perovskite material.
  • 6.8K
  • 10 Apr 2023
Topic Review
Quantum Biology and Non-Targeted Effects
Non-targeted effects (NTE) are an intriguing phenomenon where the biological responses observed in cells or tissues are not directly exposed to a stressor (e.g., ionizing radiation or chemical agents). onventional radiation biology approaches have predominantly focused on the macroscopic effects of ionizing radiation, overlooking the quantum-scale interactions that may play a crucial role in NTE. Quantum biology (QB) offers a unique perspective to explore and understand the intricate and subtle processes underlying NTE.
  • 6.8K
  • 04 Dec 2023
Topic Review
The Fibrosis-4 (FIB-4) Index
The fibrosis-4 (FIB-4) index is the first triaging tool for excluding advanced fibrosis because of its accuracy, simplicity, and cheapness, especially for general physicians or endocrinologists, although the FIB-4 index has several drawbacks. Accumulating evidence has suggested that vibration-controlled transient elastography (VCTE) and the enhanced liver fibrosis (ELF) test may become useful as the second step after triaging by the FIB-4 index. The leading cause of mortality in MAFLD is cardiovascular disease (CVD), extrahepatic malignancy, and liver-related diseases. MAFLD often complicates chronic kidney disease (CKD), resulting in increased simultaneous liver kidney transplantation. The FIB-4 index could be a predictor of not only liver-related mortality and incident hepatocellular carcinoma, but also prevalent and incident CKD, CVD, and extrahepatic malignancy.
  • 6.8K
  • 25 May 2021
Topic Review
Overcurrent Relays and Their Usage
Overcurrent relays (OCR) are used as the main protection device due to their lower cost compared to other types of relays. Overcurrent relays can be divided roughly into two types, judging by their time–current characteristic: definite-time OCRs and inverse-time OCRs.
  • 6.8K
  • 18 Feb 2022
Topic Review
Pyrido[2,3-d], [3,2-d], [3,4-d] and [4,3-d]pyrimidine Derivatives
The structures composed of a pyridopyrimidine moiety which have shown a therapeutic interest or have already been approved for use as therapeutics, including pyrido[2,3-d]pyrimidines, pyrido[3,4-d]pyrimidines, pyrido[4,3-d]pyrimidines and pyrido[3,2-d]pyrimidines.
  • 6.8K
  • 06 Apr 2022
Topic Review
Palmitoylethanolamide in Autism Spectrum Disorder
Palmitoylethanolamide (PEA) is a naturally occurring saturated N-acylethanolamine that has proven to be effective in controlling inflammation, depression, epilepsy, and pain, possibly through a neuroprotective role against glutamate toxicity. Here, we systematically reviewed all human and animal studies examining PEA and its biobehavioral correlates in ASD. Studies indicate altered serum/brain levels of PEA and other endocannabinoids (ECBs)/acylethanolamines (AEs) in ASD. Altered PEA signaling response to social exposure and altered expression/activity of enzymes responsible for the synthesis and catalysis of ECBs/AEs, as well as downregulation of the peroxisome proliferator activated receptor-α (PPAR-α) and cannabinoid receptor target GPR55 mRNA brain expression, have been reported. Stress and exposure to exogenous cannabinoids may modulate ECBs/AEs levels and expression of candidate genes for neuropsychiatric disorders, with implications for ASD. Limited research suggests that PEA supplementation reduces overall autism severity by improving language and social and nonsocial behaviors. Potential neurobiological underpinnings include modulation of immune response, neuroinflammation, neurotrophy, apoptosis, neurogenesis, neuroplasticity, neurodegeneration, mitochondrial function, and microbiota activity, possibly through peroxisome proliferator-activated receptor-α (PPAR-α) activation.
  • 6.8K
  • 08 Sep 2021
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