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Topic Review
Dispersion
A dispersion is a system in which distributed particles of one material are dispersed in a continuous phase of another material. The two phases may be in the same or different states of matter. Dispersions are classified in a number of different ways, including how large the particles are in relation to the particles of the continuous phase, whether or not precipitation occurs, and the presence of Brownian motion. In general, dispersions of particles sufficiently large for sedimentation are called suspensions, while those of smaller particles are called colloids and solutions.
  • 3.1K
  • 11 Oct 2022
Topic Review
Permanent Magnet Synchronous Motor
The most common special features and demands of the PMSMs are described in the appearance of the motor’s failures caused by uncontrolled temperature rise. In addition, heat sources and energy losses, including copper loss, core loss versus motor speed, and output power, are analyzed. Various cooling strategies are listed and discussed. Scope of this review is to develop PMSM for a heavy duty green mobility with the smart light weight materials and with the enhanced cooling approaches.
  • 3.1K
  • 30 Mar 2021
Topic Review
Electrical Transcription
Electrical transcriptions are special phonograph recordings made exclusively for radio broadcasting, which were widely used during the 'Golden Age of Radio', wherein, they provided material—from station-identification jingles and commercials to full-length programs—for use by local stations, affiliates of one of the radio networks. Physically, electrical transcriptions look much like long-playing records that were popular for decades. They differ from consumer-oriented recordings, however, in that they were "distributed to radio stations for the purpose of broadcast, and not for sale to the public.... The ET had higher quality audio than was available on consumer records" largely because they had less surface noise than commercial recordings,
  • 3.1K
  • 01 Oct 2022
Topic Review
Electron (Rocket)
Electron is a two-stage orbital expendable launch vehicle (with an optional third stage) developed by the American aerospace company Rocket Lab to service the commercial small satellite launch segment. Its Rutherford engines, manufactured in California , are the first electric-pump-fed engine to power an orbital rocket. In December 2016, Electron completed flight qualification. The first rocket was launched on 25 May 2017, reaching space but not achieving orbit due to a glitch in communication equipment on the ground. During its second flight on 21 January 2018, Electron reached orbit and deployed three CubeSats. The first commercial launch of Electron, and the third launch overall, occurred on 11 November 2018.
  • 3.1K
  • 08 Oct 2022
Topic Review
Genomics Improve Abiotic Stress Tolerance in Tomato Plant
Solanum lycopersicum L. (Solanaceae), generally known as tomato, is one of the most significant fruits that are nutritionally classified as a vegetable. It contains carotenoids (lycopene and carotene), phenolic compounds (flavonoids), vitamins (ascorbic acid, -tocopherol, vitamin A), glycoalkaloids (tomatine), and phytosterols (-sitosterol, campesterol, and stigmasterol).
  • 3.1K
  • 21 Apr 2023
Topic Review
Informal Learning
Informal learning is characterized “by a low degree of planning and organizing in terms of the learning context, learning support, learning time, and learning objectives”. It differs from formal learning, non-formal learning, and self-regulated learning, because it has no set objective in terms of learning outcomes, but an intent to act from the learner’s standpoint (e.g., to solve a problem). Typical mechanisms of informal learning include trial and error or learning-by-doing, modeling, feedback, and reflection. For learners this includes heuristic language building, socialization, enculturation, and play. Informal learning is a pervasive ongoing phenomenon of learning via participation or learning via knowledge creation, in contrast with the traditional view of teacher-centered learning via knowledge acquisition. Estimates suggest that about 70-90 percent of adult learning takes place informally and outside educational institutions. The term is often conflated, however, with non-formal learning, and self-directed learning. It is widely used in the context of corporate training and education in relation to return on investment (ROI), or return on learning (ROL). It is also widely used when referring to science education, in relation to citizen science, or informal science education. The conflated meaning of informal and non-formal learning explicates mechanisms of learning that organically occur outside the realm of traditional instructor-led programs, e.g., reading self-selected books, participating in self-study programs, navigating performance support materials and systems, incidental skills practice, receptivity of coaching or mentoring, seeking advice from peers, or participation in communities of practice, to name a few. Informal learning is common in communities where individuals have opportunities to observe and participate in social activities. Advantages of informal learning cited include flexibility and adaptation to learning needs, direct transfer of learning into practice, and rapid resolution of (work-related) problems. For improving employees' performance, task execution is considered the most important source of learning.
  • 3.1K
  • 12 Dec 2022
Topic Review
Hydrogen Bond Energy
Hydrogen bonds (HBs) play a crucial role in many physicochemical and biological processes. Theoretical methods can reliably estimate the intermolecular HB energies. Quantifying an intramolecular hydrogen bond (IHB) strength is not as straightforward as the intermolecular one. The main difficulty lies in isolating the X–H···Y interaction present within a molecule than in a dimer or a complex. However, the procedure discussed (viz. molecular tailoring approach) in this article, allows the generation of fragments so that the atoms/functional groups involved in the HB formation are parts of two different fragments. The energies of these fragments are added or substracted, using the inclusion exclusion principle in set theory, to obtained the energy of HB bond.
  • 3.1K
  • 19 May 2021
Topic Review
CRISPR Therapeutics
The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) genome editing system has been the focus of intense research in the last decade due to its superior ability to desirably target and edit DNA sequences. The applicability of the CRISPR-Cas system to in vivo genome editing has acquired substantial credit for a future in vivo gene-based therapeutic. Challenges such as targeting the wrong tissue, undesirable genetic mutations, or immunogenic responses, need to be tackled before CRISPR-Cas systems can be translated for clinical use. Hence, there is an evident gap in the field for a strategy to enhance the specificity of delivery of CRISPR-Cas gene editing systems for in vivo applications. Current approaches using viral vectors do not address these main challenges and, therefore, strategies to develop non-viral delivery systems are being explored. Peptide-based systems represent an attractive approach to developing gene-based therapeutics due to their specificity of targeting, scale-up potential, lack of an immunogenic response and resistance to proteolysis. In this review, we discuss the most recent efforts towards novel non-viral delivery systems, focusing on strategies and mechanisms of peptide-based delivery systems, that can specifically deliver CRISPR components to different cell types for therapeutic and research purposes.
  • 3.1K
  • 12 Oct 2020
Topic Review
Sociological Abstraction
Sociological abstraction refers to the process of distilling and analyzing complex social phenomena by isolating and examining specific aspects or patterns. Sociologists often use abstraction as a method to simplify the study of society, allowing them to focus on key elements and relationships within social structures. By abstracting certain concepts or variables, researchers can develop theories and models that help explain and understand various social phenomena.
  • 3.1K
  • 25 Jan 2024
Topic Review
Bucherer–Bergs Multicomponent Synthesis of Hydantoins
The Bucherer–Bergs reaction is one of the most convenient general methods for the preparation of 5-substituted and 5,5-disubstituted hydantoins (imidazolidine-2,4-diones, 2,4-dioxoimidazolidines). Generally, in this multicomponent reaction, the aldehyde or ketone in aqueous ethanol is heated at 60–70° with potassium (or sodium) cyanide and ammonium carbonate to produce directly hydantoins 1.
  • 3.1K
  • 28 Jul 2021
Topic Review
Biosynthesis Investigations of Terpenoids Antimicrobial Agents
Terpenoids, also known as isoprenoids, are one of the largest natural product families, constituting more than 40,000 primary and secondary metabolites, including monoterpenes (53%), diterpenoids (1%), sesquiterpenes (28%), and others (18%). The basic unit of terpenes is the isoprene unit (C5H8), which is a simple hydrocarbon. It is the main precursor and could be post-modified through the cytosolic mevalonate (MVA) pathway or the plastid methyl erythritol phosphate (MEP) pathway. Terpenoids are a major source of bioactive natural products. 
  • 3.1K
  • 07 Nov 2022
Topic Review
Neo-Advaita
Neo-Advaita, also called the Satsang-movement and Nondualism, is a New Religious Movement, emphasizing the direct recognition of the non-existence of the "I" or "ego," without the need of preparatory practice. Its teachings are derived from, but not authorised by, the teachings of the 20th century sage Ramana Maharshi, as interpreted and popularized by H. W. L. Poonja and several of his western students. It is part of a larger religious current called immediatism by Arthur Versluis, which has its roots in both western and eastern spirituality. Western influences are western esoteric traditions like Transcendentalism, and "New Age millennialism, self-empowerment and self-therapy". Neo-Advaita makes little use of the "traditional language or cultural frames of Advaita Vedanta", and some have criticised it for its lack of preparatory training, and regard enlightenment-experiences induced by Neo-Advaita as superficial.
  • 3.1K
  • 16 Nov 2022
Topic Review
Nitrogen, Phosphorus and Microalgal
Microalgae can be used as a source of alternative food, animal feed, biofuel, fertilizer, cosmetics, nutraceuticals and for pharmaceutical purposes. The extraction of organic constituents from microalgae cultivated in the different nutrient compositions is influenced by microalgal growth rates, biomass yield and nutritional content in terms of lipid and fatty acid production. In this context, nutrient composition plays an important role in microalgae cultivation, and depletion and excessive sources of this nutrient might affect the quality of biomass. Investigation on the role of nitrogen and phosphorus, which are crucial for the growth of algae, has been addressed. However, there are challenges for enhancing nutrient utilization efficiently for large scale microalgae cultivation. Hence, this study aims to highlight the level of nitrogen and phosphorus required for microalgae cultivation and focuses on the benefits of nitrogen and phosphorus for increasing biomass productivity of microalgae for improved lipid and fatty acid quantities. Furthermore, the suitable extraction methods that can be used to utilize lipid and fatty acids from microalgae for biofuel have also been reviewed.
  • 3.1K
  • 03 Mar 2021
Topic Review
Androgen Receptor Structure and Function
The Androgen Receptor (NR3C4, nuclear receptor subfamily 3, group C, gene 4) is a member of the steroid hormone group of nuclear receptors along with the oestrogen receptors (ERα and β isoforms, NR3A1 and NR2A2, respectively), glucocorticoid receptor (GR, NR3C1), progesterone receptor (PR, NR3C3) and mineralocorticoid receptor (MR, NR3C2).
  • 3.1K
  • 08 Mar 2021
Topic Review
Influencer Marketing
Influencer marketing (also known as influence marketing) is a form of social media marketing involving endorsements and product placement from influencers, people and organizations who have a purported expert level of knowledge or social influence in their field. Influencers are someone (or something) with the power to affect the buying habits or quantifiable actions of others by uploading some form of original—often sponsored—content to social media platforms like Instagram, YouTube, Snapchat or other online channels. Influencer marketing is when a brand enrolls influencers who have an established credibility and audience on social media platforms to discuss or mention the brand in a social media post. Influencer content may be framed as testimonial advertising.
  • 3.1K
  • 14 Oct 2022
Topic Review
Grand Power K100
The K100 is a 9×19mm semi-automatic pistol designed and built by Grand Power s.r.o. in Slovenská Ľupča, Slovakia located approximately 11 kilometers east of Banská Bystrica, Slovakia which is the region's major city.
  • 3.1K
  • 03 Nov 2022
Topic Review
Visegrád Group
The Visegrád Group, Visegrád Four, or V4, is a cultural and political alliance of four Central European countries – the Czech Republic, Hungary, Poland and Slovakia, that are members of the European Union (EU) and NATO – for the purposes of advancing military, cultural, economic and energy cooperation with one another along with furthering their integration in the EU. The Group traces its origins to the summit meetings of leaders from Czechoslovakia, Hungary, and Poland held in the Hungarian castle-town of Visegrád on 15 February 1991. Visegrád was chosen as the location for the 1991 meeting as an intentional allusion to the medieval Congress of Visegrád in 1335 between John I of Bohemia, Charles I of Hungary and Casimir III of Poland. After the dissolution of Czechoslovakia in 1993, the Czech Republic and Slovakia became independent members of the group, thus increasing the number of members from three to four. All four members of the Visegrád Group joined the European Union on 1 May 2004.
  • 3.1K
  • 15 Nov 2022
Topic Review
Sample Preparation Techniques Used in Food Analysis
Food samples are complex heterogenous matrices, where all analytes are distributed in a random manner. Food analysis involves sampling, homogenization, and sample preparation that increase the analytical accuracy and precision. Focusing on sample preparation it usually involves storage, particle size reduction, homogenization, weighting, dilution, filtration, extraction, clean-up, and derivatization. Proper sample preparation protocols result in matrix interference elimination and analyte preconcentration, thus affecting the selectivity, sensitivity, detection capability, and the overall performance of an analytical technique. The most time-consuming step in analytical method development is the optimization of the sample preparation protocol that includes analyte extraction and clean-up. Some of the most common sample preparation techniques used in food analysis are liquid-liquid extraction (LLE), solid-liquid extraction (SLE), solid-phase extraction (SPE), solid-phase microextraction (SPME), stir bar sorptive extraction (SBSE), supercritical fluid extraction (SFE), accelerated solvent extraction (ASE), ultrasonic, and Soxhlet extraction.
  • 3.1K
  • 17 Jul 2023
Topic Review
Thin-Layer Chromatography in the Screening of Botanicals
Thin-layer chromatography both in its standard (TLC) and high-performance (HPTLC) format is known as a versatile and high-throughput liquid chromatography technique, with a wide range of important applications. These applications can roughly be divided into those in direct service of life sciences (such as botany, phytochemistry and medicine, and handling rather fundamental issues such as contributing to chemotaxonomy of plants, or searching for enzyme inhibitor templates) and the more practical goals.
  • 3.1K
  • 19 Oct 2022
Topic Review
Secondary Marine Metabolites
Secondary marine metabolites are defined as molecules with a molecular weight ranging between 100 to 1000 Da and, unlike primary marine metabolites, are often found to be unique to an organism or a specific taxonomic group of the marine source. Other than marine macroorganisms such as algae, sponges, or corals, specifically marine fungi and bacteria have shown to produce novel secondary metabolites with unique as well as diverse chemical structures that may hold the key for developing novel drugs or drug leads. Secondary marine metabolites have been found in both prokaryotic and eukaryotic microorganisms, with unicellular bacteria (e.g., Bacillus sp., Pseudomonas sp.), eukaryotic fungi (e.g., Penicillium sp., Aspergillus sp.), filamentous actinomyces (e.g., Streptomyces sp.), and terrestrial plants being the most frequently studied and versatile producers. A potential clarification why organisms produce a high assortment of bioactive secondary marine metabolites is that these molecules furnish producers with a specific advantage against competing organisms and, furthermore, act as an adaptation to ecological conditions.
  • 3.1K
  • 30 Sep 2020
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