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Topic Review
Commercial Crew Development
Commercial Crew Development (CCDev) is a human spaceflight development program that is funded by the U.S. government and administered by NASA. CCDev will result in US and international astronauts flying to the International Space Station (ISS) on privately operated crew vehicles. Operational contracts to fly astronauts were awarded in September 2014 to SpaceX and Boeing. An uncrewed test flight was performed by each company in 2019. Space-X's Crew Dragon Demo-1 flight of Dragon 2 arrived at the International Space Station in March 2019 and returned via splashdown in the Atlantic Ocean. Due to a Mission Elapsed Time anomaly, the Boeing Orbital Flight Test of the CST-100 spacecraft failed to reach the station in December 2019, but completed some test objectives and performed a safe airbag landing in the New Mexico desert two days after launch. Pending completion of the demonstration flights, each company is contracted to supply six flights to ISS between 2019 and 2024. The first group of astronauts was announced on 3 August 2018.
  • 2.1K
  • 26 Oct 2022
Topic Review
Peripartum Cardiomyopathy
Peripartum cardiomyopathy (PPCM) is a condition in which heart failure and left ventricular systolic dysfunction occur in the last month of pregnancy or within months following delivery.
  • 2.1K
  • 26 Jan 2021
Topic Review
Femme Fatale
A femme fatale (/ˌfæm fəˈtɑːl/ or /ˌfɛm fəˈtɑːl/; French: [fam fatal]), sometimes called a maneater, is a stock character of a mysterious and seductive woman whose charms ensnare her lovers, often leading them into compromising, dangerous, and deadly situations. She is an archetype of literature and art. Her ability to enchant and hypnotise her victim with a spell was in the earliest stories seen as being literally supernatural; hence, the femme fatale today is still often described as having a power akin to an enchantress, seductress, vampire, witch, or demon, having power over men. In American early 20th century film, femme fatale characters were referred to as vamps, an allusion to their role as sexual vampires. The phrase is French for "fatal woman". A femme fatale tries to achieve her hidden purpose by using feminine wiles such as beauty, charm, and sexual allure. In some situations, she uses lies or coercion rather than charm. She may also make use of some subduing weapon such as sleeping gas, a modern analog of magical powers in older tales. She may also be (or imply that she is) a victim, caught in a situation from which she cannot escape; The Lady from Shanghai (a 1947 film noir) is one such example. A younger version of a femme fatale is called a fille fatale, or "fatal girl". One of the most common traits of the femme fatale includes promiscuity and the "rejection of motherhood," seen as "one of her most threatening qualities since by denying his immortality and his posterity it leads to the ultimate destruction of the male." Femmes fatales are typically villainous, or at least morally ambiguous, and always associated with a sense of mystification, and unease.
  • 2.1K
  • 02 Dec 2022
Topic Review
Organophosphorus Compounds Degradation by EC3.1.8.2
The organophosphorus substances, including pesticides and nerve agents (NAs), represent highly toxic compounds. Standard decontamination procedures place a heavy burden on the environment. Given their continued utilization or existence, considerable efforts are being made to develop environmentally friendly methods of decontamination and medical countermeasures against their intoxication. Enzymes can offer both environmental and medical applications. One of the most promising enzymes cleaving organophosphorus compounds is the enzyme with enzyme commission number (EC): 3.1.8.2, called diisopropyl fluorophosphatase (DFPase) or organophosphorus acid anhydrolase from Loligo Vulgaris or Alteromonas sp. JD6.5, respectively. Structure, mechanisms of action and substrate profiles are described for both enzymes. Wild-type (WT) enzymes have a catalytic activity against organophosphorus compounds, including G-type nerve agents. Their stereochemical preference aims their activity towards less toxic enantiomers of the chiral phosphorus center found in most chemical warfare agents. Site-direct mutagenesis has systematically improved the active site of the enzyme. These efforts have resulted in the improvement of catalytic activity and have led to the identification of variants that are more effective at detoxifying both G-type and V-type nerve agents. Some of these variants have become part of commercially available decontamination mixtures.
  • 2.1K
  • 24 Dec 2020
Topic Review
Development of Agents with Biological Activities by Umbelliferone
Umbelliferone (UMB), known as 7-hydroxycoumarin, hydrangine, or skimmetine, is a naturally occurring coumarin in the plant kingdom, mainly from the Umbelliferae family that possesses a wide variety of pharmacological properties. In addition, the use of nanoparticles containing umbelliferone may improve anti-inflammatory or anticancer therapy. Also, its derivatives are endowed with great potential for therapeutic applications due to their broad spectrum of biological activities such as anti-inflammatory, antioxidant, neuroprotective, antipsychotic, antiepileptic, antidiabetic, antimicrobial, antiviral, and antiproliferative effects.
  • 2.1K
  • 22 Dec 2023
Topic Review
Expression, Regulation, and Physiological Relevance of Skin Aquaporins
The skin is the largest organ of the human body, serving as an effective mechanical barrier between the internal milieu and the external environment. The skin is widely considered the first-line defence of the body, with an essential function in rejecting pathogens and preventing mechanical, chemical, and physical damages. Keratinocytes are the predominant cells of the outer skin layer, the epidermis, which acts as a mechanical and water-permeability barrier. The epidermis is a permanently renewed tissue where undifferentiated keratinocytes located at the basal layer proliferate and migrate to the overlying layers. 
  • 2.1K
  • 27 May 2022
Topic Review
Stride Length
Stride length was defined as the distance measured parallel to the line of progression, including two consecutive steps. Stride width was defined as side-to side distance between the heel of the current foot and heel of the next opposite foot. On the other hand, step width was determined as the distance between the outermost borders of two consecutive footprints. The standard deviation of the three variables (stride length) was used to represent the variability of the stride length.
  • 2.1K
  • 22 Jul 2021
Topic Review
Japan’s Commercial Real Estate
Japan commercial real estate investment market has, in general, seen a number of scholarly papers in the past, they are concentrated largely on its listed real estate investment segment. There is a significant knowledge gap concerning the non-listed value-add real estate funds’ risk-adjusted performance and portfolio diversification benefits in an institutional investors’ portfolio. This is particularly true in the case of specific countries e.g. in Japan.
  • 2.1K
  • 10 May 2022
Topic Review
Informational Social Influence
Social proof is a psychological and social phenomenon wherein people copy the actions of others in an attempt to undertake behavior in a given situation. The term was coined by Robert Cialdini in his 1984 book Influence: Science and Practice, and the concept is also known as informational social influence. Social proof is considered prominent in ambiguous social situations where people are unable to determine the appropriate mode of behavior, and is driven by the assumption that the surrounding people possess more knowledge about the current situation. The effects of social influence can be seen in the tendency of large groups to conform. This is referred to in some publications as the herd behavior. Although social proof reflects a rational motive to take into account the information possessed by others, formal analysis shows that it can cause people to converge too quickly upon a single distinct choice, so that decisions of even larger groups of individuals may be grounded in very little information (see information cascades). Social proof is one type of conformity. When a person is in a situation where they are unsure of the correct way to behave, they will often look to others for clues concerning the correct behavior. When "we conform because we believe that others' interpretation of an ambiguous situation is more accurate than ours and will help us choose an appropriate course of action", it is informational social influence. This is contrasted with normative social influence wherein a person conforms to be liked or accepted by others. Social proof often leads not only to public compliance (conforming to the behavior of others publicly without necessarily believing it is correct) but also private acceptance (conforming out of a genuine belief that others are correct). Social proof is more powerful when being accurate is more important and when others are perceived as especially knowledgeable. In 2020, a young scientist from Poland , Michal Klichowski, proved that this phenomenon also applies to interactions with artificial intelligence. His results show a new AI proof mechanism: AI that people have more and more contact with is becoming a new source of information about how to behave and what decisions to take.
  • 2.1K
  • 28 Nov 2022
Topic Review
Biopolymer-Based Composites from Agricultural Waste Biomass
Natural fibers are derived from a variety of flora and fauna sources and are utilized in the production of textiles and other commodities. These materials are recognized for their capacity to decompose naturally, their ability to endure over time, and their positive impact on the ecosystem. Fibers derived from agricultural waste biomass pertain to fibers procured from the residual components of crops, including but not limited to straw, stalks, leaves, and husks.
  • 2.1K
  • 14 Jun 2023
Topic Review
Digital Transformation
The conceptual definition of digital transformation (DT) is composed of five corporate activities (AT Kearney) that increase a business’s competitiveness in response to changes in the business environment, which are triggered by new digital technologies, such as big data (BD), artificial intelligence (AI), the Internet of things (IoT), smart factories (SF), cyber-physical systems (CPS), and interoperability (IOP). DT claims to maintain a sustainable business and positively impact overall business performance.
  • 2.1K
  • 28 Jun 2021
Topic Review
Nucleophilic Substitution
A nucleophilic substitution is a class of chemical reactions in which an electron-rich chemical species (known as a nucleophile) replaces a functional group within another electron-deficient molecule (known as the electrophile). The molecule that contains the electrophile and the leaving functional group is called the substrate. The most general form of the reaction may be given as the following: The electron pair (:) from the nucleophile (Nuc) attacks the substrate (R-LG) and bonds with it. Simultaneously, the leaving group (LG) departs with an electron pair. The principal product in this case is R-Nuc. The nucleophile may be electrically neutral or negatively charged, whereas the substrate is typically neutral or positively charged. An example of nucleophilic substitution is the hydrolysis of an alkyl bromide, R-Br under basic conditions, where the attacking nucleophile is OH− and the leaving group is Br−. Nucleophilic substitution reactions are common in organic chemistry (especially introductory organic chemistry). Nucleophiles often attack a saturated aliphatic carbon. Less often, they may attack an aromatic or unsaturated carbon.
  • 2.1K
  • 26 Oct 2022
Topic Review
Collaborative Platforms for Sustainable E-Learning in Higher Education
E-learning platforms have become more and more complex. Their functionality included in learning management systems is extended with collaborative platforms, which allow better communication, group collaboration, and face-to-face lectures. Universities are facing the challenge of advanced use of these platforms to fulfil sustainable learning goals. Better usability and attractiveness became essential in successful e-learning platforms, especially due to the more intensive interactivity expected from students.
  • 2.1K
  • 09 Aug 2022
Topic Review
Phytochemical Properties, Extraction, and Pharmacological Benefits of Naringin
Naringin is a nutritional flavanone glycoside that has been shown to be effective in the treatment of a few chronic disorders associated with ageing. Citrus fruits contain a common flavone glycoside that has specific pharmacological and biological properties. Naringin, a flavone glycoside with a range of intriguing characteristics, is abundant in citrus fruits. Naringin has been shown to have a variety of biological, medicinal, and pharmacological effects. Naringin is hydrolyzed into rhamnose and prunin by the naringinase, which also possesses l-rhamnosidase activity. D-glucosidase subsequently catalyzes the hydrolysis of prunin into glucose and naringenin. Naringin is known for having anti-inflammatory, antioxidant, and tumor-fighting effects. Numerous test animals and cell lines have been used to correlate naringin exposure to asthma, hyperlipidemia, diabetes, cancer, hyperthyroidism, and osteoporosis.
  • 2.1K
  • 03 Aug 2023
Topic Review
Nanomaterials’ Effect on Asphalt Mixtures
The desire for high-performance and long-lasting asphalt pavements significantly pushed the modification of the conventional paving asphalt binders. To cope with such demand, the use of nanomaterials for the asphalt binder modification seems promising, as with a small amount of modification an important enhancement of the asphalt mixture mechanical performance can be attained. Several studies already evaluated the effects of the modifications with nanomaterials, mostly focusing on the asphalt binder properties and rheology, and the positive findings encouraged the study of modified asphalt mixtures.
  • 2.1K
  • 27 Oct 2020
Topic Review
Pratylenchus
Root-lesion nematodes of the genus Pratylenchus are migratory endoparasites belonging to the family Pratylenchidae (Nematoda, Tylenchina), with around 100 species recognized today.
  • 2.1K
  • 21 Jan 2021
Topic Review
Autophagy and Apoptotic Pathways in Multiple Myeloma
Multiple myeloma (MM) is caused by aberrant plasma cells (PCs) in the bone marrow (BM), representing 1% of neoplastic diseases and 13% of hematological neoplasms. MM is a challenging cancer to diagnose and treat.
  • 2.1K
  • 16 Jan 2023
Topic Review
Coconut Palm
The price of traditional sources of nutrients used in animal feed rations is increasing steeply in developed countries due to their scarcity, high demand from humans for the same food items, and expensive costs of raw materials. Thus, one of the alternative sources is coconut parts or coconut as a whole fruit. Coconut is known as the ‘tree of abundance’, ‘tree of heaven’, and ‘tree of life’ owing to its numerous uses, becoming a very important tree in tropical areas for its provision of food, employment, and business opportunities to millions of people. Coconut contains a rich profile of macro and micronutrients that vary depending on the parts and how they are used. It is frequently chosen as an alternative source of protein and fiber. Its uses as an antibacterial agent, immunomodulant, and antioxidant further increase its importance. Using coconut oil in ruminant feed helps to minimize methane gas emissions by 18–30%, and to reduce dry matter intake up to 4.2 kg/d. The aquaculture sectors also use coconut palm as an alternative source because it significantly improves the digestion, growth, lipid metabolism, health, and antioxidative responses. However, coconut is not widely used in poultry diets although it has adequate amount of protein and carbohydrate due to anti-nutritional factors such cellulose (13%), galactomannan (61%), and mannan (26%). 
  • 2.1K
  • 31 Aug 2022
Topic Review
Bâton de Commandement
A bâton de commandement, bâton percé or perforated baton is a name given by archaeologists to a particular prehistoric artifact that has been much debated. The name bâtons de commandement was the name first applied to the class of artifacts, but it makes an assumption of function; the name bâton percé, meaning "pierced rod", or "perforated baton" (the term used by the British Museum) is a more recent term, and is descriptive of form rather than any presumed function. Many are decorated with carved or engraved animals, and the most usual explanation of their use is that they were used for straightening spears and arrows, and as spear-throwers.
  • 2.1K
  • 28 Sep 2022
Topic Review
Human Dental Pulp Stem Cells
Human dental pulp stem cells (hDPSCs) are adult mesenchymal stem cells (MSCs) obtained from dental pulp and derived from the neural crest. They can differentiate into odontoblasts, osteoblasts, chondrocytes, adipocytes and nerve cells, and they play a role in tissue repair and regeneration.
  • 2.1K
  • 29 May 2023
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