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Topic Review
Bifunctional Beta-Lactam Antibiotics
The molecular structure of β-lactam antibiotics can be modified either to introduce another β-lactam ring (the pharmacophore conferring bactericidal activities to these molecules), or to add other pharmacophores that modify their pharmacological properties and spectrum of action.
  • 2.5K
  • 07 Feb 2021
Topic Review
Unmanned Aerial Vehicles for Search and Rescue
The use of unmanned aerial vehicles (UAVs) in search and rescue (SAR) can greatly enhance the task success rates in reaching inaccessible or dangerous areas, performing challenging operations, and providing real-time monitoring and modeling of the situation.
  • 2.5K
  • 03 Aug 2023
Topic Review
Nonformal Learning
Non-formal learning includes various structured learning situations which do not either have the level of curriculum, syllabus, accreditation and certification associated with 'formal learning', but have more structure than that associated with 'informal learning', which typically take place naturally and spontaneously as part of other activities. These form the three styles of learning recognised and supported by the OECD. Examples of non-formal learning include swimming sessions for toddlers, community-based sports programs, and programs developed by organisations such as the Boy Scouts, the Girl Guides, community or non-credit adult education courses, sports or fitness programs, professional conference style seminars, and continuing professional development. The learner's objectives may be to increase skills and knowledge, as well as to experience the emotional rewards associated with increased love for a subject or increased passion for learning.
  • 2.5K
  • 16 Nov 2022
Topic Review
Environmental Factors Affect Parathyroid Hormone and Calcitonin
Calciotropic hormones, parathyroid hormone (PTH) and calcitonin are involved in the regulation of bone mineral metabolism and maintenance of calcium and phosphate homeostasis in the body. Therefore, an understanding of environmental and genetic factors influencing PTH and calcitonin levels is crucial. Genetic factors are estimated to account for 60% of variations in PTH levels.
  • 2.5K
  • 22 Sep 2022
Topic Review
Yarovaya Law
The Yarovaya law (in Russian: Закон Яровой, transliteration: Zakon Jarovoy), also Yarovaya package/bag, is a set of two Russia n federal bills, 374-FZ and 375-FZ, passed in 2016. The bills amend previous counter-terrorism law and separate laws regulating additional counter-terror and public safety measures. It is known to the public under the last name of one of its creators—Irina Yarovaya. The amendments included an expansion of authority for law enforcement agencies, new requirements for data collection and mandatory decoding in the telecommunications industry, as well as the increased regulation of evangelism, including a ban on the performance of "missionary activities" in non-religious settings.
  • 2.5K
  • 12 Oct 2022
Topic Review
Cyanopsitta
Spix's macaw (Cyanopsitta spixii), also known as the little blue macaw, is a macaw native to Brazil. It is a member of tribe Arini in the subfamily Arinae (Neotropical parrots), part of the family Psittacidae (the true parrots). It was first described by German naturalist Georg Marcgrave, when he was working in the State of Pernambuco, Brazil in 1638 and it is named for German naturalist Johann Baptist von Spix, who collected a specimen in 1819 on the bank of the Rio São Francisco in northeast Bahia in Brazil. The bird is a medium-size parrot weighing about 300 grams (11 oz), smaller than most of the large macaws. Its plumage is various shades of blue, with a grey-blue head, light blue underparts, and vivid blue upperparts. Males and females are almost identical in appearance, however the females are slightly smaller on average. Currently there are no known survivors of the species outside of captivity. The species inhabited riparian Caraibeira (Tabebuia aurea) woodland galleries in the drainage basin of the Rio São Francisco within the Caatinga dry forest climate of interior northeastern Brazil. It had a very restricted natural habitat due to its dependence on the tree for nesting, feeding and roosting. It feeds primarily on seeds and nuts of Caraiba and various Euphorbiaceae (spurge) shrubs, the dominant vegetation of the Caatinga. Due to deforestation in its limited range and specialized habitat, the bird has been rare in the wild throughout the twentieth century. It has always been very rare in captivity, partly due to the remoteness of its natural range. The IUCN regard the Spix's macaw as extinct in the wild. Its last known stronghold in the wild was in northeastern Bahia, Brazil and sightings are very rare. After a 2000 sighting of a male bird, the next and last sighting was in 2016. The species is now maintained through a captive breeding program at several conservation organizations under the aegis of the Brazilian government. It is listed on CITES Appendix I, which makes trade illegal except for legitimate conservation, scientific or educational purposes. The Brazilian Chico Mendes Institute for Biodiversity Conservation (ICMBio) is conducting a project Ararinha-Azul with an associated plan to restore the species to the wild as soon as sufficient breeding birds and restored habitat are available.
  • 2.5K
  • 20 Oct 2022
Topic Review
Ozone Depletion by Rocket Launches
Rocket launches used for space exploration continue to gain popularity as the human population grows and technology advances toward the future. Large increases in rocket launch demand could come about for a variety of reasons, including national decisions regarding security, space exploration, significant reductions in launch costs, or the emergence of new markets such as space tourism, manufacturing, or solar power. Rocket launches can affect the natural environment, most specifically the composition of the atmosphere as they travel through it. A major environmental problem faced today is the depletion of the ozone layer in the atmosphere by rockets and other molecular species such as chlorofluorocarbons. Up to forty percent of the total ozone present in the wake of a rocket is destroyed from rocket plumes. Ozone concentrations are calculated using ultraviolet and visible light radiometers attached to rockets. Calculations analyzed from these radiometers are where scientists first noticed the depletion of ozone caused by rockets.
  • 2.5K
  • 01 Nov 2022
Topic Review
Toxicology of Deoxynivalenol
Deoxynivalenol is a toxic compound produced by filamentous fungi and represents a threat to public health. It is not possible to totally extinguish fungal contamination in crops such as wheat and corn and thereby avoid the production of this toxin.
  • 2.5K
  • 03 Mar 2022
Topic Review
Pyonephrosis: Ultrasound and Computed Tomography
Ultrasound and computed tomography represent the imaging processes of choice in the diagnosis and staging pyonephrosis in emergency settings. 
  • 2.5K
  • 21 Apr 2021
Topic Review
Behavioural Archaeology
Behavioural archaeology is an archaeological theory that expands upon the nature and aims of archaeology in regards to human behaviour and material culture. The theory was first published in 1975 by American archaeologist Michael B. Schiffer and his colleagues J. Jefferson Reid, and William L. Rathje. The theory proposes four strategies that answer questions about past, and present cultural behaviour. It is also a means for archaeologists to observe human behaviour and the archaeological consequences that follow. The theory was developed as a reaction to changes in archaeological thought, and expanding archaeological practise during the mid-late 20th century. It reacted to the increasing number of sub-disciplines emerging within archaeology as each came with their own unique methodologies. The theory was also a reaction to the processual thought process that emerged within the discipline some years prior. In recent years the use of behavioural archaeology has been regarded as a significant contribution to the archaeological community. The strategies outlined by Schiffer and his colleagues have developed into sub-disciplines or methodologies that are used and well-regarded in contemporary archaeological practise. Behavioural archaeology has positive effects on the method in which archaeologists use to reconstruct human behaviour.
  • 2.5K
  • 30 Nov 2022
Biography
William Gilbert
William Gilbert (24 May 1544 – 30 November 1603), also known as Gilberd, was an English physician, physicist and natural philosopher. He passionately rejected both the prevailing Aristotelian philosophy and the Scholastic method of university teaching. He is remembered today largely for his book De Magnete (1600), and is credited as one of the originators of the term "electricity". He is regar
  • 2.5K
  • 01 Dec 2022
Topic Review
Probiotics in the Treatment of Rotavirus Gastrointestinal Infections
Enteric viruses, including the rotavirus, norovirus, and adenoviruses, are the most common cause of acute gastroenteritis. The rotavirus disease is especially prevalent among children, and studies over the past decade have revealed complex interactions between rotaviruses and the gut microbiota. One way to treat and prevent dysbiosis is the use of probiotics as an antiviral agent.
  • 2.5K
  • 20 Dec 2022
Topic Review
Power Electronics and Battery Cooling Methods
The global promotion of electric vehicles (EVs) through various incentives has led to a significant increase in their sales. The prolonged charging duration remains a significant hindrance to the widespread adoption of these vehicles and the broader electrification of transportation. While DC-fast chargers have the potential to significantly reduce charging time, they also result in high power demands that the grid and hence may require local battery energy storage systems (BESS) for peak shaving applications. A high power demand also creates high losses and cooling methods play an important role in overall efficiency, sound pollution, system size, reliability, and lifetime of the system.  
  • 2.5K
  • 27 Feb 2023
Topic Review
Aardwolf
The Aardwolf (Proteles cristata) is a unique and intriguing species of hyena found primarily in eastern and southern Africa. Despite its resemblance to its larger relatives, the Aardwolf is a specialized insectivore, primarily feeding on termites and other insects. With its distinctive mane, elongated snout, and nocturnal habits, the Aardwolf occupies a specialized ecological niche and plays a vital role in controlling insect populations within its ecosystem.
  • 2.5K
  • 28 Feb 2024
Topic Review
Development of Thermal Barrier Coatings
Thermal barrier coating is critical for thermal insulation technology, making the underlying base metal capable of operating at a melting temperature of 1150 °C. By increasing the temperature of incoming gases, engineers can improve the thermal and mechanical performance of gas turbine blades and the piston cylinder arrangement. Developments in the field of thermal barrier coatings (TBCs) have made this material suitable for use in a variety of fields, including the aerospace and diesel engine industries. Changes in the turbine blade microstructure brought on by its operating environment determine how long and reliable it will be. In addition, the effectiveness of multi-layer, composite and functionally graded coatings depends heavily on the deposition procedures used to create them. 
  • 2.5K
  • 11 Oct 2022
Topic Review
Zeaxanthin and Lutein in Humans
Many factors in the environment (including radiation, pathogens, and various stresses) prompt internal formation of oxidants that orchestrate beneficial adjustments in human metabolism and but can also lead to damage and disease. To prevent adverse effects of these oxidants, humans require antioxidants and anti-inflammatories, many of which are vitamins and other essential micronutrients that must be consumed with the diet. The xanthophylls zeaxanthin and lutein are unique human micronutrients that protect the integrity and function of biological membranes – especially in the human eye and brain.
  • 2.5K
  • 16 Feb 2021
Topic Review
Conservation and Restoration of Cultural Heritage
The conservation and restoration of cultural heritage focuses on protection and care of tangible cultural heritage, including artworks, architecture, archaeology, and museum collections. Conservation activities include preventive conservation, examination, documentation, research, treatment, and education. This field is closely allied with conservation science, curators and registrars.
  • 2.5K
  • 25 Nov 2022
Topic Review
STAT3
STAT3 is an important transcription factor that regulates cell growth and proliferation by regulating gene transcription of a plethora of genes.
  • 2.5K
  • 26 Aug 2021
Topic Review
Auditory neurons in inner ear
These neurons transmit auditory information in the form of electric signals from sensory hair cells to the first auditory nuclei of the brain stem, the cochlear nuclei. Congenital and acquired neurosensory hearing loss affects millions of people worldwide. An increasing body of evidence suggest that the primary auditory neurons degenerate due to noise exposure and aging more readily than sensory cells, and thus, auditory neurons are a primary target for regenerative therapy. A better understanding of the development and function of these neurons is the ultimate goal for long-term maintenance, regeneration, and stem cell re-placement therapy.
  • 2.5K
  • 04 Jan 2021
Topic Review
Membrane Fouling
Membrane-based separation has gained increased popularity over the past few decades, particularly reverse osmosis (RO). A major impediment to the improved performance of membrane separation processes, in general, is membrane fouling. Fouling has detrimental effects on the membrane’s performance and integrity, as the deposition and accumulation of foulants on its surface and/or within its pores leads to a decline in the permeate flux, deterioration of selectivity, and permeability, as well as a significantly reduced lifespan. Several factors influence the fouling-propensity of a membrane, such as surface morphology, roughness, hydrophobicity, and material of fabrication. Generally, fouling can be categorized into particulate, organic, inorganic, and biofouling. Efficient prediction techniques and diagnostics are integral for strategizing control, management, and mitigation interventions to minimize the damage of fouling occurrences in the membranes. To improve the antifouling characteristics of RO membranes, surface enhancements by different chemical and physical means have been extensively sought after. Moreover, research efforts have been directed towards synthesizing membranes using novel materials that would improve their antifouling performance. 
  • 2.5K
  • 18 May 2021
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