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Topic Review
Atomic Radii of the Elements (Data Page)
The atomic radius of a chemical element is the distance from the center of the nucleus to the outermost shell of an electron. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. Depending on the definition, the term may apply only to isolated atoms, or also to atoms in condensed matter, covalently bound in molecules, or in ionized and excited states; and its value may be obtained through experimental measurements, or computed from theoretical models. Under some definitions, the value of the radius may depend on the atom's state and context. Atomic radii vary in a predictable and explicable manner across the periodic table. For instance, the radii generally decrease rightward along each period (row) of the table, from the alkali metals to the noble gases; and increase down each group (column). The radius increases sharply between the noble gas at the end of each period and the alkali metal at the beginning of the next period. These trends of the atomic radii (and of various other chemical and physical properties of the elements) can be explained by the electron shell theory of the atom; they provided important evidence for the development and confirmation of quantum theory.
  • 3.9K
  • 02 Dec 2022
Topic Review
Types of Bacterial Movement
Skin and wound infections are serious medical problems, and the diversity of bacteria makes such infections difficult to treat. Bacteria possess many virulence factors, among which motility plays a key role in skin infections. This feature allows for movement over the skin surface and relocation into the wound. The aim is to review the type of bacterial movement and to indicate the underlying mechanisms than can serve as a target for developing or modifying antibacterial therapies applied in wound infection treatment. Five types of bacterial movement are distinguished: appendage-dependent (swimming, swarming, and twitching) and appendage-independent (gliding and sliding). All of them allow bacteria to relocate and aid bacteria during infection. Swimming motility allows bacteria to spread from ‘persister cells’ in biofilm microcolonies and colonise other tissues. Twitching motility enables bacteria to press through the tissues during infection, whereas sliding motility allows cocci (defined as non-motile) to migrate over surfaces. Bacteria during swarming display greater resistance to antimicrobials. Molecular motors generating the focal adhesion complexes in the bacterial cell leaflet generate a ‘wave’, which pushes bacterial cells lacking appendages, thereby enabling movement.
  • 3.9K
  • 06 Jul 2023
Topic Review
Bioactive Glass
Bioactive glass (BAG) consist of known biocompatible and bioactive minerals, including fluorapatite (FAP), wollastonite, diopside, and tricalcium phosphate. A bioactive material can interact with the biological environment to elicit a specific biological response and they can be osteoconductive or osteoinductive. Bioactive Glasses are amorphous solids with the irregular organization of atoms, optically transparent, and brittle consisting of silica networks. They possesses bioactivity and antimicrobial properties as presented n following sections. The bioactivity of BAGs involves several steps; BAGs immediately undergo ionic dissolution and glass degradation via the exchange of H+ ions in the solution and Na+ and Ca2+ from the glass network. BAG exhibits antimicrobial properties against various pathogens, e.g pathogens associated with sinusitis and osteomyelitis.
  • 3.9K
  • 22 Oct 2020
Topic Review
Laser Forming Process
Laser forming is an emerging manufacturing process capable of producing either uncomplicated and complicated shapes by employing a concentrated heating source. The heat source movement creates local softening, and a plastic strain will be induced during the rise of temperature and the subsequent cooling. This contactless forming process may be used for the simple bending of sheets and tubes or fabrication of doubly-curved parts. Different studies have been carried out over recent years to understand the mechanism of forming and predicting the bending angle. The analysis of process parameters and search for optimized manufacturing conditions are among the most discussed topics. This review describes the main recent findings in the laser forming of single and multilayer sheets, composite and fiber-metal laminate plates, force assisted laser bending, tube bending by laser beam, the optimization technique implemented for process parameters selection and control, doubly-curved parts, and the analytical solutions in laser bending. The main focus is set to the researches published since 2015.
  • 3.9K
  • 21 Nov 2020
Topic Review
Baddeley's Model of Working Memory
Baddeley's model of working memory is a model of human memory proposed by Alan Baddeley and Graham Hitch in 1974, in an attempt to present a more accurate model of primary memory (often referred to as short-term memory). Working memory splits primary memory into multiple components, rather than considering it to be a single, unified construct. Baddeley & Hitch proposed their three-part working memory model as an alternative to the short-term store in Atkinson & Shiffrin's 'multi-store' memory model (1968). This model is later expanded upon by Baddeley and other co-workers to add a fourth component, and has become the dominant view in the field of working memory. However, alternative models are developing, providing a different perspective on the working memory system. The original model of Baddeley & Hitch was composed of three main components: the central executive which acts as a supervisory system and controls the flow of information from and to its slave systems: the phonological loop and the visuo-spatial sketchpad. The phonological loop stores verbal content, whereas the visuo-spatial sketchpad caters to visuo-spatial data. Both the slave systems only function as short-term storage centers. In 2000, Baddeley added a third slave system to his model, the episodic buffer. Baddeley & Hitch's argument for the distinction of two domain-specific slave systems in the older model was derived from experimental findings with dual-task paradigms. Performance of two simultaneous tasks requiring the use of two separate perceptual domains (i.e. a visual and a verbal task) is nearly as efficient as performance of the tasks individually. In contrast, when a person tries to carry out two tasks simultaneously that use the same perceptual domain, performance is less efficient than when performing the tasks individually. A fourth component of Baddeley's model was added 25 years later to complement the central executive system. The third slave system was designated as episodic buffer. It is considered a limited-capacity system that provides temporary storage of information by conjoining information from the subsidiary systems, and long-term memory, into a single episodic representation.
  • 3.9K
  • 04 Nov 2022
Topic Review
Production of Edible Films and Coatings
Generally, edible films and coatings are the primary forms of edible food packaging. The differences between edible films and coatings lie in their physical form and application process. Edible films are obtained as solid laminated sheets and then used as a food wrap that can be removed or consumed with food, whereas coatings are applied to foods in liquid form by coating, spraying, and immersion. After drying, an edible layer over the food is formed, and it can either be removed or consumed.
  • 3.9K
  • 21 Jul 2023
Topic Review
Transition Metal Dichalcogenides
In recent years, the material characteristics and properties of transition metal dichalcogenide (TMDCs) have gained research interest in various fields, such as electronics, catalytic, energy storage. In particular, many researchers have been focusing on the applications of TMDCs in dealing with environmental pollution. TMDCs provide a unique opportunity to develop higher-value applications related to environmental matters. This work highlights the applications of TMDCs contributing to pollution reduction in (i) gas sensing technology, (ii) gas adsorption and removal, (iii) wastewater treatment, (iv) fuel cleaning, and (v) carbon dioxide valorisation and conversion. Overall, the applications of TMDCs have successfully demonstrated the advantages of contributing to environmental conversation due to their special properties. The challenges and bottlenecks of implementing TMDCs in the actual industry are also highlighted. More efforts need to be devoted to overcoming the hurdles to maximize the potential of TMDCs implementation in the industry.
  • 3.9K
  • 27 Oct 2020
Topic Review
Personal Values in Learning Approaches
Personal values play a significant role when adopting learning approaches by individuals during their studies. Particularly in higher education, these values significantly influence the character that individuals play within their learning community and ultimately influence their academic achievements. The purpose of this paper is to investigate personal values in their choice of learning approaches and, subsequently, how it impacts one’s academic achievements.
  • 3.9K
  • 21 Jul 2021
Topic Review
Treating Delusional Disorder with Antipsychotics
Delusional disorder (DD) has been considered a treatment-resistant disorder, with antipsychotics acknowledged as the best. It is possible that the discovery of the right drug could turn treatment resistance into treatment response.
  • 3.9K
  • 29 Dec 2022
Topic Review
GLP-1 Receptor Agonists
GLP-1 receptor agonists stimulate GLP-1R to promote insulin secretion, whereas DPP4 inhibitors slow GLP-1 degradation. Both approaches are incretin-based therapies for T2D. In addition to GLP-1 analogs, small nonpeptide GLP-1RAs such as LY3502970, TT-OAD2, and PF-06882961 have been considered as possible therapeutic alternatives.
  • 3.9K
  • 23 Jun 2022
Topic Review
Electrode Passivation
The main reason for electrode passivation is adsorption/deposition of a passivating compound on working electrode surface. The most pronounced consequences are the decrease of the rate of electrode reaction resulting in the shift of half-wave or peak potential to more negative (in the case of cathodic reaction) or to more positive (in the case of anodic reaction) potentials and in the decrease of peak current, which is especially in the case of pulsed technique influenced by this rate. 
  • 3.9K
  • 22 Feb 2021
Topic Review
Medical Ethnobotany of India
The medical ethnobotany of India is the study of Indian medicinal plants and their traditional uses. Plants have been used in India for treatment of disease and health maintenance for thousands of years, and remain important staples of health and folk medicine for millions. Indians today utilize plants for both primary medical care (principally in Rural and undeserved areas) and as supplementary treatment alongside modern medical science. It is estimated that 70% of rural Indians use traditional plant based remedies for primary healthcare needs. This reliance of plants for medicine is consistent with trends widely observed in the developing world, where between 65% and 80% of people use medicinal plant remedies. Herbal medicine in India is largely guided by folk medicine, both in codified cultural practices shared widely (Ayurveda, Siddha, Unani), and highly localized practices unique to individual tribes or tribal groups (Adivasi). Between 3,000 and 5,000 species of medicinal plants grow in India with roughly 1,000 threatened with extinction. Of these, more than 2,400 plant species have been documented for medicinal use.
  • 3.9K
  • 01 Nov 2022
Topic Review
Eco-Friendly Clothing Market in Bangladesh
Organic cotton clothing development in the fashion industry could play an important role in textile and environmental pollution and create new business opportunities for green clothes.  Consumer environmental concerns and consumer attitudes positively impact the OCC purchase willingness of Bangladeshi consumers. Also, the authenticity and fashionable of OCC products have a significant impact on Bangladeshi consumer purchase intention. Product Performance found an indirect effect on Bangladeshi consumers’ intention. 
  • 3.9K
  • 27 May 2022
Topic Review
Compensatory Carry-Over Action Model (CCAM)
The Compensatory Carry-Over Action Model (CCAM) is innovative as most behavioral theories only model single activity. The CCAM, however, models different single activities—such as physical activity and nutrition —and how they change as a result of one another. Such lifestyle activities are assumed to be formed by higher-level goals, which can drive activity volitionally or unconsciously, and are rather unspecific. They become specific because of activities that are subjectively seen as leading to this goal. Each activity must be intended, pursued, and controlled. Specific resources ensure that individuals have the chance to translate their intentions into activity and that they resist distractors. Compensation and transfer (also called carry-over) operate between the different activities. If people devote all of their energy to one domain and believe that no resources remain for the other activity, compensation can help to attain goals. It is also possible that an individual successfully performs one activity, and existing or developing resources may be transferred to another activity.
  • 3.9K
  • 16 Dec 2020
Topic Review
Space and Upper Atmosphere Research Commission
Established in its modern form on 16 September 1961 by an executive order of President of Pakistan, it is headquartered in Karachi, Sindh Province of Pakistan. Part of the Strategic Plans Division (SPD) of Pakistan Armed Forces, which is currently headquartered at the Chakalala Military District under the control of the Pakistan Air Force ; the space programmes recorded number of pioneering accomplishments in space flight during the initial years of its establishment. The country's first satellite, Badr-I, was built by the SUPARCO and launched from the Xichang Satellite Launch Center, China on July 16, 1990. However, during the meantime, the space programme suffered many setbacks, difficulties, and problems that partly slowed the progress of the space programme. The bureaucratic influence and politicization further lagged the space programme and many projects were cancelled by the superior authorities. Over the years, SUPARCO expanded and it now has several installations all over the country. It has multi-lateral and bilateral international agreements. SUPARCO has been quite dormant in recent years and also have failed to make any breakthroughs. SUPARCO's science and research is mainly focused and concentrated on understanding of the Solar system, Space weather, astrophysics, astronomical observation, climatic studies, space and telemedicine, remote sensing and the Earth observation.
  • 3.9K
  • 02 Nov 2022
Topic Review
Jewish Views on Evolution
Jewish views on evolution includes a continuum of views about the theory of evolution, experimental evolution, the origin of life, age of the universe, evolutionary creationism, and theistic evolution. Today, many Jews accept the theory of evolution and do not see it as incompatible with traditional Judaism, reflecting the emphasis of prominent rabbis such as the Vilna Gaon and Maimonides on the ethical rather than factual significance of scripture.
  • 3.9K
  • 10 Oct 2022
Topic Review
Layered Double Hydroxides
Layered double hydroxides (LDHs) are anionic clays which have found applications in a wide range of fields, including medicine (especially in drug delivery and release), environment (to remediate pollution), biotechnology, as precursors for catalysts, and in electrochemical applications (electrocatalysts, sensors, oxygen evolution reaction (OER), energy storage, fuel cells, etc.). To be used in electrochemistry  they should possess electrical conductivity which can be ensured by the presence of metals able to give reversible redox reactions in a proper potential window. The metal centers can act as redox mediators to catalyze reactions for which the required overpotential is too high, and this is a key aspect for the development of processes and devices where the control of charge transfer reactions plays an important role.
  • 3.9K
  • 30 Mar 2021
Topic Review Peer Reviewed
Chytrids in Soil Environments: Unique Adaptations and Distributions
Chytridiomycota (zoosporic true fungi) have a consistent presence in soils and have been frequently identified within many diverse terrestrial environments. However, Chytridiomycota and other early-diverging fungi have low representation in whole-genome sequencing databases compared to Dikarya. New molecular techniques have provided insights into the diversity and abundance of chytrids in soils and the changes in their populations both spatially and temporally. Chytrids complete their life cycle within rapidly changing soil environments where they may be more common within micropores due to protection from predation, desiccation, and extreme temperatures. Reproductive and morphological changes occur in response to environmental changes including pH, fluctuating nutrient concentrations, and metals at levels above toxic thresholds. Rhizoids share some features of hyphae, including the spatial regulation of branching and the ability to attach, adapt to, and proliferate in different substrates, albeit on a microscale. Soil chytrids provide a pool of novel enzymes and proteins which enable a range of lifestyles as saprotrophs or parasites, but also can be utilised as alternative tools with some biotechnological applications. Thus, 3D live-cell imaging and micromodels such as MicroCT may provide insight into zoospore functions and rhizoid plasticity, respectively, in response to various conditions. A combination of classical techniques of soil chytrid baiting with simultaneous molecular and ecological data will provide insights into temporal population changes in response to environmental change. The authors emphasise the need to review and improve DNA-based methodologies for identifying and quantifying chytrids within the soil microbiome to expand our knowledge of their taxonomy, abundance, diversity, and functionality within soil environments.
  • 3.9K
  • 22 May 2023
Topic Review
Graphene Oxide-Based Anticorrosive Coatings
Graphene oxide was extensively used in the last few years due to its remarkable assets and proved to have a significant contribution to composite materials. Concerning the graphene-based coatings, the synthesis methods, protective function, anticorrosion mechanism, feasible problems, and some methods to improve the overall properties were highlighted. Regarding the contribution of the nanostructure used to improve the capability of the material, several modification strategies for graphene oxide along with the synergistic effect exhibited when functionalized with other compounds were mainly discussed.
  • 3.9K
  • 10 Dec 2020
Topic Review
Medium-Entropy Alloy
The objective of this study is to strengthen the FCC structued medium-entropy alloy using the hard carbides.
  • 3.9K
  • 26 Aug 2020
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