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Topic Review
Reform Boehm System (Clarinet)
The Boehm system is a fingering system for the flute and the clarinet, as a Reform Boehm system the corresponding handle system for the clarinet, connected to a clarinet body, which has a different inner bore than in the original Boehm clarinet , with the aim of producing a different sound character together with another mouthpiece.
  • 2.5K
  • 27 Oct 2022
Topic Review
Oxidative Stress Biomarkers
Oxidative stress biomarkers can be used to detect oxidative damages occurring concomitantly in many cellular structures, which may cause a deterioration of function, including apoptosis and necrosis. There is an intimate relationship between oxidative stress, inflammation, and functional impairment, resulting in various diseases affecting the entire human body.
  • 2.5K
  • 20 Aug 2021
Topic Review
Natural Killer Cells
When facing an acute viral infection, our immune systems need to function with finite precision to enable the elimination of the pathogen, whilst protecting our bodies from immune-related damage. In many instances however this ‘perfect balance’ is not achieved, factors such as ageing, cancer, autoimmunity and cardiovascular disease all skew the immune response which is then further distorted by viral infection. SARS-CoV-2 infection skews the immune response towards an overwhelmingly inflammatory phenotype. Restoration of NK cell effector functions has the potential to correct the delicate immune balance required to effectively overcome SARS-CoV-2 infection.
  • 2.5K
  • 27 Oct 2020
Topic Review
CFD Modelling of Slurry Flows
Slurry pipe transport has directed the efforts of researchers for decades, not only for the practical impact of this problem, but also for the challenges in understanding and modelling the complex phenomena involved. The increase in computer power and the diffusion of multipurpose codes based on Computational Fluid Dynamics (CFD) have opened up the opportunity to gather information on slurry pipe flows at the local level, in contrast with the traditional approaches of simplified theoretical modelling which are mainly based on a macroscopic description of the flow. 
  • 2.5K
  • 15 Sep 2021
Topic Review
The Livability of Open Public Spaces during Nighttime
The transformations of contemporary life are reflected not only in the way people use open public spaces but also in the time people use them—nighttime activities are becoming more frequent. High daytime temperatures in certain periods of the year, during the summer and other seasons, discourage the development of outdoor activities in open public spaces during daytime. The urban heat island impact of pollution has significantly reduced the quality of living conditions in cities for daily outdoor activities. On the other hand, the hectic contemporary lifestyle in an urban context creates a lack of free time during the day, because leisure is compatible with working hours, where the focus on working during the day reduces the possibility of free time . These restrictions have changed the patterns of human behavior in urban environments, shifting the focus of free time to nighttime. The livability of open public spaces in an urban context is determined by usage and the frequency, duration, and activities of users. People’s activities in public spaces, according to Jan Gehl, can be divided into three types: necessary, optional, and social behaviors. According to him, the physical environment and spatial features of the area play an important role when engaging in outdoor activities, except for the necessary behaviors (including going to school, going to work, shopping, etc.).
  • 2.5K
  • 28 Jun 2022
Topic Review
Mutagens Applied to Microalgae for Random Mutagenesis
Microalgal biomass and metabolites can be used as a renewable source of nutrition, pharmaceuticals and energy to maintain or improve the quality of human life. Microalgae’s high volumetric productivity and low impact on the environment make them a promising raw material in terms of both ecology and economics. To optimize biotechnological processes with microalgae, improving the productivity and robustness of the cell factories is a major step towards economically viable bioprocesses. The success of a random mutagenesis approach using microalgae is determined by multiple factors involving the treatment of the cells before, during and after the mutagenesis procedure. Using photosynthetic microalgae, the supply of light quality and quantity, as well as the supply of carbon and nitrogen, are the most important factors. Besides the environmental conditions, the type of mutagen, its concentration and exposure time are among the main factors affecting the mutation result.
  • 2.5K
  • 01 Aug 2022
Topic Review
Evolutionary Theory of the Self
When trying to understand the self in terms of the brain, neuroscientists have found contradictory results and paradoxes. Nevertheless, Gonzalo Munevar has argued that neuroscience in an evolutionary context can give a proper explanation of the self. His Evolutionary Theory of the Self depends on, “the ability by the brain to coordinate new sensory information in light of the organism’s internal states and in the context of its personal history and genetic inheritance." His theory is an alternative conception for the explanation of the self, which takes into account the evolutionary biology of the brain. Organisms that are highly complex execute the function of telling self from other with the brain and the immune system. To fulfill the function of recognizing self from other, the brain uses past experiences and genetic inheritance (e.g. survival, reproduction). The self is defined by these functions that distinguish an organisms from other organisms, which allow them to act as one whole entity in social and physical environments. Simply put, the theory revolves around the idea that the brain constitutes the self, which represents itself in a variety of internal states. The brain/self evolves for action to be able to interact with social and physical environments. It is suggested that the brain performs a complex list of tasks to complete these interactions to distinguish self from other. This defines the brain to be characteristically distributive to complete complex tasks, and thus suggests that the self is also distributive. Therefore, the Evolutionary Theory of the Self detours from the traditional conceptions that include the self being a centralized, unitary mechanism that is both conscious (sense of self) and compiled of a collection of episodic memories. Alternatively, it suggests that the conception of self is mostly unconscious, and the brain evolves from past experiences and genetic inheritance to create the evolutionary self. In Munevar’s study, “fMRI Study of Self vs. Others’ Attributions of Traits Consistent with Evolutionary Understanding of the Self,” he aimed to demonstrate the experimental feasibility of this conception of the self as a distributive system, and discovered results complimenting the Evolutionary Theory of the Self while resolving the contradictions and paradoxes of traditional conceptions of self.
  • 2.5K
  • 25 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
Research on Meditation
For the purpose of this article, research on meditation concerns research into the psychological and physiological effects of meditation using the scientific method. In recent years, these studies have increasingly involved the use of modern scientific techniques and instruments, such as fMRI and EEG which are able to directly observe brain physiology and neural activity in living subjects, either during the act of meditation itself, or before and after a meditation effort, thus allowing linkages to be established between meditative practice and changes in brain structure or function. Since the 1950s hundreds of studies on meditation have been conducted, but many of the early studies were flawed and thus yielded unreliable results. Contemporary studies have attempted to address many of these flaws with the hope of guiding current research into a more fruitful path. In 2013, researchers at Johns Hopkins, publishing in the Journal of the American Medical Association, identified 47 studies that qualify as well-designed and therefore reliable. Based on these studies, they concluded that there is moderate evidence that meditation reduces anxiety, depression, and pain, but no evidence that meditation is more effective than active treatment (drugs, exercise, other behavioral therapies). A 2017 commentary was similarly mixed. The process of meditation, as well as its effects, is a growing subfield of neurological research. Modern scientific techniques and instruments, such as fMRI and EEG, have been used to study how regular meditation affects individuals by measuring brain and bodily changes.
  • 2.5K
  • 16 Nov 2022
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
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
Leo
Leo, the Lion, is one of the zodiac constellations, known for its distinctive shape resembling a lion's mane and head. It is one of the oldest recognized constellations, dating back to ancient civilizations such as the Mesopotamians, Egyptians, and Greeks. Leo is home to several bright stars and notable deep-sky objects.
  • 2.5K
  • 15 Mar 2024
Topic Review
Biosensors for Malaria Biomarkers
This entry discusses recent advances in the development of biosensors for the purposes of malaria diagnostics. It underscore relevant challenges that have defined the gap between biosensor development and their successful utilization in routine clinical practice within resource-limitted settings. It proposes a way to think about developing biosensors that are suitable for biomedical diagnostics applications.
  • 2.5K
  • 30 Oct 2020
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
AmigaOS
AmigaOS is a family of proprietary native operating systems of the Amiga and AmigaOne personal computers. It was developed first by Commodore International and introduced with the launch of the first Amiga, the Amiga 1000, in 1985. Early versions of AmigaOS required the Motorola 68000 series of 16-bit and 32-bit microprocessors. Later versions were developed by Haage & Partner (AmigaOS 3.5 and 3.9) and then Hyperion Entertainment (AmigaOS 4.0-4.1). A PowerPC microprocessor is required for the most recent release, AmigaOS 4. AmigaOS is a single-user operating system based on a preemptive multitasking kernel, called Exec. It includes an abstraction of the Amiga's hardware, a disk operating system called AmigaDOS, a windowing system API called Intuition, and a desktop environment and file manager called Workbench. The Amiga intellectual property is fragmented between Amiga Inc., Cloanto, and Hyperion Entertainment. The copyrights for works created up to 1993 are owned by Cloanto. In 2001, Amiga Inc. contracted AmigaOS 4 development to Hyperion Entertainment and, in 2009 they granted Hyperion an exclusive, perpetual, worldwide license to AmigaOS 3.1 in order to develop and market AmigaOS 4 and subsequent versions. On December 29, 2015, the AmigaOS 3.1 source code leaked to the web; this was confirmed by the licensee, Hyperion Entertainment.
  • 2.5K
  • 07 Nov 2022
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
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
Dietary Intervention of Chronic Diseases in Menopause
Menopause is associated with an increased prevalence of obesity, metabolic syndrome, cardiovascular diseases, and osteoporosis. These diseases and unfavorable laboratory values, which are characteristic of this period in women, can be significantly improved by eliminating and reducing dietary risk factors. Changing dietary habits during perimenopause is most effectively achieved through nutrition counseling and intervention. To reduce the risk factors of all these diseases, and in the case of an already existing disease, dietary therapy led by a dietitian should be an integral part of the treatment. 
  • 2.5K
  • 29 Dec 2023
Topic Review
Vitamin C
Vitamin C is implicated in various bodily functions due to its unique properties in redox homeostasis. Moreover, vitamin C also plays a great role in restoring the activity of 2-oxoglutarate and Fe2+ dependent dioxygenases (2-OGDD), which are involved in active DNA demethylation (TET proteins), the demethylation of histones, and hypoxia processes. Therefore, vitamin C may be engaged in the regulation of gene expression or in a hypoxic state.
  • 2.5K
  • 05 Feb 2021
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
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