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Topic Review
N-Acetylcysteine in Trichotillomania
N-acetylcysteine (NAC) (C5H9NO3S) is the acetylated precursor of the amino acid L-cysteine and functions as a glutamate modulator and antioxidant. It is widely known as a mucolytic, an antidote for acetaminophen overdose, and a nephroprotective agent for contrast administration. Trichotillomania (TTM), excoriation disorder, onychophagia, and onychotillomania are categorized as body focused repetitive behavior (BFRB) disorders, causing damage to the skin, hair, and/or nails with clinically significant psychosocial consequences.
  • 4.5K
  • 13 Jun 2022
Topic Review
MMR Vaccine Controversy
A controversy surrounding the combined measles, mumps, and rubella (MMR) vaccine started with the 1998 publication of a fraudulent research paper in The Lancet linking the vaccine to colitis and autism spectrum disorders. The claims in the paper were widely reported, leading to a sharp drop in vaccination rates in the UK and Ireland and increases in the incidence of measles and mumps, resulting in deaths and serious permanent injuries. Following the initial claims in 1998, multiple large epidemiological studies were undertaken. Reviews of the evidence by the Centers for Disease Control and Prevention, the American Academy of Pediatrics, the Institute of Medicine of the US National Academy of Sciences, the UK National Health Service, and the Cochrane Library all found no link between the MMR vaccine and autism. An investigation by journalist Brian Deer found that Andrew Wakefield, the author of the original research paper linking the vaccine to autism, had multiple undeclared conflicts of interest, had manipulated evidence, and had broken other ethical codes. The Lancet paper was partially retracted in 2004 and fully retracted in 2010, when Lancet's editor-in-chief Richard Horton described it as "utterly false" and said that the journal had been deceived. Wakefield was found guilty by the General Medical Council of serious professional misconduct in May 2010 and was struck off the Medical Register, meaning he could no longer practise as a doctor in the UK. In 2011, Deer provided further information on Wakefield's improper research practices to the British Medical Journal, which in a signed editorial described the original paper as fraudulent. The scientific consensus is that there is no link between the MMR vaccine and autism and that the vaccine's benefits greatly outweigh its risks. Wakefield's paper was described as "perhaps, the most damaging medical hoax of the last 100 years". Physicians, medical journals, and editors have described Wakefield's actions as fraudulent and tied them to epidemics and deaths.
  • 4.5K
  • 21 Oct 2022
Topic Review
Biopolymers’ Processing Methods
The biopolymer functionality depends on several factors apart from their structure and composition, such as the type, quality, and quantity of the solvent used and the processing technique used to build the final structure that will determine the interaction of the materials. The main processing techniques for bio-based polymers from renewable sources are discussed in detail.
  • 4.5K
  • 16 May 2023
Topic Review
Lipid Peroxidation
Lipid peroxidation refers to the process in which lipids are oxidized to generate lipid peroxides as a primary product. Cellular lipid peroxidation can occur through different reactions, but they can be categorized into enzyme and non-enzyme dependent reactions. The primary substrates in lipid peroxidation reactions are polyunsaturated lipids since carbon-carbon double bonds are susceptible to reactive oxygen species, such as the hydroxyl radical (HO•), which is a key radical that participates in peroxidation reactions.
  • 4.5K
  • 14 Dec 2020
Topic Review
Halt and Catch Fire
In computer engineering, Halt and Catch Fire, known by the assembly mnemonic HCF, is an idiom referring to a computer machine code instruction that causes the computer's central processing unit (CPU) to cease meaningful operation, typically requiring a restart of the computer. It originally referred to a fictitious instruction in IBM System/360 computers, making a joke about its numerous non-obvious instruction mnemonics. With the advent of the MC6800, a design flaw was discovered by the programmers. Due to incomplete opcode decoding, two illegal opcodes, 0x9D and 0xDD, will cause the program counter on the processor to increment endlessly, which renders the processor useless. Those codes have been unofficially named HCF. During the design process of MC6802, engineers originally planned to remove this instruction, but kept it as-is for testing purposes. As a result, HCF was officially recognized as a real instruction. Later, HCF became a humorous catch-all term for instructions that may freeze a processor, including intentional instructions for testing purposes, and unintentional illegal instructions. Some are considered hardware defects, and if the system is shared, a malicious user can execute it to launch a denial-of-service attack. In the case of real instructions, the implication of this expression is that, whereas in most cases in which a CPU executes an unintended instruction (a bug in the code) the computer may still be able to recover, in the case of an HCF instruction there is, by definition, no way for the system to recover without a restart. The expression "catch fire" is a facetious exaggeration of the speed with which the CPU chip would be switching some bus circuits, causing them to overheat and burn.
  • 4.5K
  • 04 Nov 2022
Topic Review
DESCRIPTION OF THE MITOCHONDRIAL PORIN VDAC1 AND ITS DISEASE RELEVANCE
Mitochondrial porins or voltage-dependent anionic channels (VDAC) are nonspecific channels that determine the permeability of the mitochondrial outer membrane (MEM). Its molecular mass oscillates around 28 to 36 kDa. These channels represent the most abundant proteins of the MEM. They are freely permeable to hydrophilic solutes and the limit of exclusion of metabolites is 3 to 6 kDa. These channels are the main route for the diffusion of ions such as pyruvate and ATP, among others. It has been proposed that the transport of these metabolites regulates the cellular energy supply. This review focus on some of the main aspects of the VDAC porins and its relevance in some physiological processes related with cancer and neurodegeneration diseases. 
  • 4.5K
  • 30 Oct 2020
Biography
Robert Kearns
Robert William Kearns PhD (March 10, 1927 – February 9, 2005) was an American engineer, educator and inventor who invented the intermittent windshield wiper systems used on most automobiles from 1969 to the present. His first patent for the invention was filed on December 1, 1964. Kearns won one of the best known patent infringement cases against Ford Motor Company (1978–1990) and a case a
  • 4.5K
  • 23 Nov 2022
Topic Review
Strain Rate Tensor
In continuum mechanics, the strain rate tensor is a physical quantity that describes the rate of change of the deformation of a material in the neighborhood of a certain point, at a certain moment of time. It can be defined as the derivative of the strain tensor with respect to time, or as the symmetric component of the gradient (derivative with respect to position) of the flow velocity. The strain rate tensor is a purely kinematic concept that describes the macroscopic motion of the material. Therefore, it does not depend on the nature of the material, or on the forces and stresses that may be acting on it; and it applies to any continuous medium, whether solid, liquid or gas. On the other hand, for any fluid except superfluids, any gradual change in its deformation (i.e. a non-zero strain rate tensor) gives rise to viscous forces in its interior, due to friction between adjacent fluid elements, that tend to oppose that change. At any point in the fluid, these stresses can be described by a viscous stress tensor that is, almost always, completely determined by the strain rate tensor and by certain intrinsic properties of the fluid at that point. Viscous stress also occur in solids, in addition to the elastic stress observed in static deformation; when it is too large to be ignored, the material is said to be viscoelastic.
  • 4.5K
  • 02 Dec 2022
Topic Review
Biomimicry
Biomimicry can be defined as the branch of science for developing technology by mimicking nature, where forms and structures of creatures are the basic sources of inspiration to come up with optimized design solutions.
  • 4.5K
  • 12 Mar 2021
Topic Review
Microemulsion Design for Acne Therapy
Acne represents a dermatologic condition with a high prevalence, being characterized by a complex pathogenesis. Its high recurrence frequently encountered in clinical practice will affect the patient’s quality of life. Most of the treatment algorithms require at least one topical formulation, being recommended to be applied on affected areas for a long period. To treat such a versatile skin condition, smart topical vehicles capable of entrap anti-acne compounds can be considered a good option, compared with conventional systems generally used at the moment. In this direction, microemulsions are appreciated for their superior profile in matters of drug delivery, especially for challenging substances with hydrophilic or lipophilic patterns. Designed as transparent and thermodynamically stable systems, with a small number of key ingredients, microemulsion-based formulations were characterized in the present review as unique structures able to pass the skin barrier and sustain a targeted therapy in acne pathology.
  • 4.5K
  • 30 Nov 2020
Topic Review
History of X-ray Research in Colonial India
This is the stroy of the beginning of X-ray research in colonial India and its progress to understand the India's respectable position globally in X-ray researh in modern times.The history of X-ray research in colonial India started with the procurement of X-ray tube by Dr. Mahendralal Sircar within six months of the discovery of X-rays at the Indian Association for the Cultivation of Science (IACS). The first application of X-rays for clinical purposes was done, in private capacity, independently by Dr. Sircar and Sir J.C. Bose. After his return from England in 1921, C.V. Raman initiated serious X-ray scattering studies in the structure of matter at the IACS which proliferated to all parts of India and laid the foundation stone of modern X-ray research in India.
  • 4.5K
  • 29 Jun 2022
Topic Review
Chemistry of Chalcone and Its Derivatives
Chalcone is a collective group of ketones (flavonoids) that has a three-carbon α,β-unsaturated carbonyl group attached to two aromatic rings. Other chemical names of chalcone include benzyl acetophenone or benzylideneacetophenone. They are produced by certain plant species such as Angelica, Glycyrrhiza, Humulus, and Scutellaria as precursors to the biosynthesis of flavonoids and isoflavonoids and intermediates to the synthesis of heterocyclic compounds with biologically interesting properties such as pyrazolines, isoxazoles, cyanopyridines and pyrimidines.
  • 4.5K
  • 25 Oct 2022
Topic Review
Collagen Injectables for Aesthetic and Regenerative Medicine Applications
Soft tissues diseases significantly affect patients quality of life and usually require targeted, costly and sometimes constant interventions. With the average lifetime increase, a proportional increase of age-related soft tissues diseases has been witnessed. Due to this, the last two decades have seen a tremendous demand for minimally invasive one-step resolutive procedures. Intensive scientific and industrial research has led to the recognition of injectable formulations as a new advantageous approach in the management of complex diseases that are challenging to treat with conventional strategies. Among them, collagen-based products are revealed to be one of the most promising among bioactive biomaterials-based formulations. Collagen is the most abundant structural protein of vertebrate connective tissues and, because of its structural and non-structural role, is one of the most widely used multifunctional biomaterials in the health-related sectors, including medical care and cosmetics. Indeed, collagen-based formulations are historically considered as the “gold standard” and from 1981 have been paving the way for the development of a new generation of fillers. A huge number of collagen-based injectable products have been approved worldwide for clinical use and have routinely been introduced in many clinical settings for both aesthetic and regenerative surgery. 
  • 4.5K
  • 06 May 2023
Topic Review
Lockheed Martin Compact Fusion Reactor
The Lockheed Martin Compact Fusion Reactor (CFR) is a proposed nuclear fusion reactor project at Lockheed Martin’s Skunk Works. Its high-beta configuration, which implies that the ratio of plasma pressure to magnetic pressure is greater than or equal to 1 (compared to tokamak designs' 0.05), allows a compact fusion reactor (CFR) design and expedited development. The CFR chief designer and technical team lead, Thomas McGuire studied fusion as a source of space propulsion in response to a NASA desire to improve travel times to Mars.
  • 4.5K
  • 17 Oct 2022
Topic Review
Spray Drying for Oils Encapsulation
This is a entry focused on the application of spray drying technology for the edible oils encapsulation. This entry covered most of the relevant works have done recently on the encapsulation of oils by spray drying. The factors affecting the process of encapsulation and the application in food with the properties of the final product.The application of the spray drying technique in the food industry for the production of a broad range of ingredients has become highly desirable compared to other drying techniques. Recently, the spray drying technique has been applied extensively for the production of functional foods, pharmaceuticals and nutraceuticals. Encapsulation using spray drying is highly preferred due to economic advantages compared to other encapsulation methods. Encapsulation of oils using the spray drying technique is carried out in order to enhance the handling properties of the products and to improve oxidation stability by protecting the bioactive compounds. Encapsulation of oils involves several parameters—including inlet and outlet temperatures, total solids, and the type of wall materials—that significantly affect the quality of final product.
  • 4.5K
  • 19 Apr 2022
Topic Review
Android Malware Detection Using ML
This systematic review discussed ML-based Android malware detection techniques. It critically evaluated 106 carefully selected articles and highlighted their strengths and weaknesses as well as potential improvements. The ML-based methods for detecting source code vulnerabilities were also discussed, because it might be more difficult to add security after the app is deployed. Therefore, this paper aimed to enable researchers to acquire in-depth knowledge in the field and to identify potential future research and development directions.
  • 4.5K
  • 19 Aug 2021
Topic Review
Tendencies Affecting Growth and Cultivation of Genus Spirulina
Spirulina, a kind of blue-green algae, is one of the Earth’s oldest known forms of life. Spirulina grows best in very alkaline environments, although it may flourish across a wide variety of pH values. There are several techniques for growing Spirulina spp., ranging from open systems such as ponds and lakes, which are vulnerable to contamination by animals and extraterrestrial species, to closed systems such as photovoltaic reactors, which are not. Most contaminated toxins come from other toxic algae species that become mixed up during harvest, necessitating the study of spirulina production processes at home. Lighting, temperature, inoculation volume, stirring speed, dissolved particles, pH, water quality, and overall micronutrient richness are only a few of the environmental parameters influencing spirulina production.
  • 4.5K
  • 08 Dec 2022
Topic Review
Stimuli-responsive materials
Smart or stimuli-responsive materials are an emerging class of materials used for tissue engineering and drug delivery. A variety of stimuli (including temperature, pH, redox-state, light, and magnet fields) are being investigated for their potential to change a material’s properties, interactions, structure, and/or dimensions. The specificity of stimuli response, and ability to respond to endogenous cues inherently present in living systems provide possibilities to develop novel tissue engineering and drug delivery strategies (for example materials composed of stimuli responsive polymers that self-assemble or undergo phase transitions or morphology transformations). Herein, smart materials as controlled drug release vehicles for tissue engineering are described, highlighting their potential for the delivery of precise quantities of drugs at specific locations and times promoting the controlled repair or remodeling of tissues.
  • 4.5K
  • 24 Jul 2020
Topic Review
Blood Pressure Sensors
In our unique transdisciplinary approach, we studied the fundamentals of blood pressure and examined its measuring modalities while focusing on their clinical use and sensing principles to identify material functionalities. Then, we carefully reviewed various categories of functional materials utilized in sensor building blocks allowing for comparative analysis of the performance of a wide range of materials throughout the sensor operational-life cycle. Not only this provides essential data to enhance the materials’ properties and optimize their performance, but also, it highlights new perspectives and provides suggestions to develop the next generation pressure sensors for clinical use.
  • 4.5K
  • 10 Apr 2021
Topic Review
Cytokines in Inflammatory Disease
This review aims to briefly discuss a short list of a broad variety of inflammatory cytokines. Numerous studies have implicated that inflammatory cytokines exert important effects with regard to various inflammatory diseases, yet the reports on their specific roles are not always consistent. They can be used as biomarkers to indicate or monitor disease or its progress, and also may serve as clinically applicable parameters for therapies. Yet, their precise role is not always clearly defined. Thus, in this entry, researchers focus on the existing literature dealing with the biology of cytokines interleukin (IL)-6, IL-1, IL-33, tumor necrosis factor-alpha (TNF-α), IL-10, and IL-8. We will briefly focus on the correlations and role of these inflammatory mediators in the genesis of various inflammatory impacts.
  • 4.5K
  • 13 Oct 2021
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