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Topic Review
Hybrid Biocomposites
Bio-based composites are reinforced polymeric materials in which one of the matrix and reinforcement components or both are from bio-based origins. The biocomposite industry has recently drawn great attention for diverse applications, from household articles to automobiles. This is owing to their low cost, biodegradability, being lightweight, availability, and environmental concerns over synthetic and nonrenewable materials derived from limited resources like fossil fuel. The focus has slowly shifted from traditional biocomposite systems, including thermoplastic polymers reinforced with natural fibers, to more advanced systems called hybrid biocomposites. Hybridization of bio-based fibers/matrices and synthetic ones offers a new strategy to overcome the shortcomings of purely natural fibers or matrices. By incorporating two or more reinforcement types into a single composite, it is possible to not only maintain the advantages of both types but also alleviate some disadvantages of one type of reinforcement by another one. 
  • 3.1K
  • 13 Dec 2020
Topic Review
Mechanisms of Antibiotic Resistance
Bacteria can exhibit two types of antibiotic resistance: intrinsic and acquired. While intrinsic resistance is determined by naturally occurring mechanisms conferred by inherent structural and/or functional features of the bacteria, the acquired resistance results from the changes in the bacterial genome. These consist of mutations in antibiotic-targeted genes or the acquisition of exogenous DNA conferring resistance, horizontally transferred by plasmids, bacteriophages, transposons, or other mobile genetic elements. Many independent mechanisms of bacterial resistance to antibiotics have been identified, including primarily modification of the antibiotic target, changes in the cell envelope’s permeability, active pumping of the antibiotic out of the cell (so-called efflux system), and enzymatic inactivation.
  • 3.1K
  • 25 Apr 2023
Topic Review
Philo
Philo of Alexandria (/ˈfaɪloʊ/; Ancient Greek:; Hebrew: יְדִידְיָה הַכֹּהֵן‎, romanized: Yedidia (Jedediah) HaCohen; c. 20 BCE – c. 50 CE), also called Philo Judaeus, was a Hellenistic Jewish philosopher who lived in Alexandria, in the Roman province of Egypt. Philo used philosophical allegory to harmonize Jewish scripture, mainly the Torah, with Greek philosophy. His method followed the practices of both Jewish exegesis and Stoic philosophy. His allegorical exegesis was important for some Christian Church Fathers, but he had very little reception history within the Rabbinic Judaism. He adopted allegorical instead of literal interpretations of the Hebrew Bible. Some scholars hold that his concept of the Logos as God's creative principle influenced early Christology. Other scholars deny direct influence but say that Philo and Early Christianity borrow from a common source. The only event in Philo's life that can be decisively dated is his participation in the embassy to Rome in 40 CE. He represented the Alexandrian Jews in a delegation to the Roman Emperor Gaius (Caligula) following civil strife between the Alexandrian Jewish and Greek communities. The story of this event, and a few other biographical details, are found in Josephus and in Philo's own works, especially in Legatio ad Gaium (Embassy to Gaius) of which only two of the original five volumes survive. The thought of Philo was largely inspired by Aristobulus of Paneas and the Alexandrian School, concerning his work "Wisdom of Solomon" and the occupations of the Therapeutæ and the Essenes.
  • 3.1K
  • 04 Nov 2022
Topic Review
Solar PV Monitoring
Solar Photovoltaic (PV) energy is a clean, attractive, and secure source of electricity generation. Due to its expanse usage around the globe, the development of an advanced monitoring method is crucial. PV performance can be affected by various environmental factors such as soiling, temperature, irradiance etc. Thus, solar PV accuracy and performance can be improved by employing an efficient solar PV real-time monitoring system. 
  • 3.1K
  • 12 Aug 2021
Topic Review
Quantum-classical system
A quantum-classical system is a system consisting of two interacting subsystems, one of which behaves classically, and the other requires a quantum description. 
  • 3.1K
  • 29 Oct 2020
Topic Review
Type I Collagen
Type I collagen, the predominant protein of vertebrates, assembles into fibrils that orchestrate the form and function of bone, tendon, skin, and other tissues. Collagen plays roles in hemostasis, wound healing, angiogenesis, and biomineralization, and its dysfunction contributes to fibrosis, atherosclerosis, cancer metastasis, and brittle bone disease.
  • 3.1K
  • 26 Jan 2021
Topic Review
Advanced Combustion for Improving Thermal Efficiency
Improving thermal efficiency and reducing carbon emissions are the permanent themes for internal combustion (IC) engines. Improving thermal efficiency and reducing fuel consumption and greenhouse gas (GHG) emissions motivate the technological progress of the automobile and engine industry.
  • 3.1K
  • 14 Sep 2022
Topic Review
Forensic Toxicology
Forensic toxicology is the use of toxicology and disciplines such as analytical chemistry, pharmacology and clinical chemistry to aid medical or legal investigation of death, poisoning, and drug use. The primary concern for forensic toxicology is not the legal outcome of the toxicological investigation or the technology utilized, but rather the obtainment and interpretation of results. A toxicological analysis can be done to various kinds of samples. A forensic toxicologist must consider the context of an investigation, in particular any physical symptoms recorded, and any evidence collected at a crime scene that may narrow the search, such as pill bottles, powders, trace residue, and any available chemicals. Provided with this information and samples with which to work, the forensic toxicologist must determine which toxic substances are present, in what concentrations, and the probable effect of those chemicals on the person. In the United States, forensic toxicology can be separated into 3 disciplines: Postmortem toxicology, human performance toxicology, and forensic drug testing (FDT). Postmortem toxicology includes the analysis of biological specimens taken from an autopsy to identify the effect of drugs, alcohol, and poisons. A wide range of biological specimens may be analyzed including blood, urine, gastric contents, oral fluids, hair, tissues, and more. The forensic toxicologist works with pathologists, medical examiners, and coroners to help determine the cause and manner of death. In human performance toxicology, a dose-response relationship between a drug(s) present in the body and the effects on the body are examined. This field of forensic toxicology is responsible for building and implementing laws such as driving under the influence of alcohol or drugs. Lastly, forensic drug testing (FDT) is the detection of drug use among individuals in the workplace, sport doping, drug-related probation, and new job applicant screenings. Determining the substance ingested is often complicated by the body's natural processes (see ADME), as it is rare for a chemical to remain in its original form once in the body. For example: heroin is almost immediately metabolised into another substance and further to morphine, making detailed investigation into factors such as injection marks and chemical purity necessary to confirm diagnosis. The substance may also have been diluted by its dispersal through the body; while a pill or other regulated dose of a drug may have grams or milligrams of the active constituent, an individual sample under investigation may only contain micrograms or nanograms.
  • 3.1K
  • 09 Nov 2022
Topic Review
Podophyllotoxin
Podophyllotoxin is an aryltetralin-type lignan isolated from species of Podophyllum. Two most common sources are the rhizomes of Podophyllum peltatum (American mayapple) and Sinopodophyllum hexandrum Royle (Barberry family). The podophyllotoxin extract has been documented for its use as a laxative, and as a remedy for various medical complications such as gonorrhea, tuberculosis, menstrual disorders, psoriasis, dropsy, cough, syphilis and venereal warts.
  • 3.1K
  • 27 Apr 2021
Topic Review
Organelle-Targeted Fluorescent Probes
Fluorescent chemical probes have been extensively used to study biochemical events within live cells. The advent of super-resolution imaging techniques and the availability of a wide variety of fluorescent probes enable effective subcellular tracking of transient metabolites and signaling molecules that are involved in important physiological processes. Probes targeting specific organelles such as mitochondria and lysosomes have been used routinely to monitor organelle functions and have become invaluable tools for the investigation of disease-relevant pathways. These probes efficiently target subcellular organelles; however, considering the complexity and diversity of biochemical processes inside the cells, probes that are not only specific to target organelles but also tailored to applications are highly desirable. 
  • 3.1K
  • 18 Jan 2021
Topic Review
Medical Applications of Hybrid Hydrogels Containing Natural Polymers
Hybrid hydrogels definition is still debatable. They are defined either as a complex composed  chemically or physically cross-linking structures, or it refers to systems combining different polymers and/or with nanoparticles, such as plasmonic, magnetic, and carbonaceous nanoparticles, among others, or they are constituted by chemically, functionally, and morphologically distinct features from at least two different classes of molecules, which can include biologically active polymers as polysaccharides and/or proteins, peptides, or nano/microstructures, interconnected via physical or chemical means.
  • 3.1K
  • 29 Mar 2022
Topic Review
The Importance of Capsules in Dry Powder Inhalers
Capsule-based dry powder inhalers (cDPI) use a hard capsule that contains a powder formulation which consists of a mixture of a micronized drug and a carrier usually the lactose, known for its good lung tolerance. The capsule is either inserted into the device during manufacturer or by the patient prior to use. After perforating, opening or cut the capsule in the device, patients take a deep and rapid breath to inhale the powder, using air as the vector of drug displacement. The system is simple, relatively cheap and characterized by a lower carbon footprint than that of pressurized metered dose inhalers. 
  • 3.1K
  • 29 Mar 2022
Topic Review
WebRTC
WebRTC (Web Real-Time Communication) is a free and open-source project providing web browsers and mobile applications with real-time communication (RTC) via application programming interfaces (APIs). It allows audio and video communication to work inside web pages by allowing direct peer-to-peer communication, eliminating the need to install plugins or download native apps. Supported by Apple, Google, Microsoft, Mozilla, and Opera, WebRTC specifications have been published by the World Wide Web Consortium (W3C) and the Internet Engineering Task Force (IETF). According to the webrtc.org website, the purpose of the project is to "enable rich, high-quality RTC applications to be developed for the browser, mobile platforms, and IoT devices, and allow them all to communicate via a common set of protocols".
  • 3.1K
  • 25 Oct 2022
Topic Review
Sierpinski Number
In number theory, a Sierpiński number is an odd natural number k such that [math]\displaystyle{ k \times 2^n + 1 }[/math] is composite for all natural numbers n. In 1960, Wacław Sierpiński proved that there are infinitely many odd integers k which have this property. In other words, when k is a Sierpiński number, all members of the following set are composite: If the form is instead [math]\displaystyle{ k \times 2^n - 1 }[/math], then k is a Riesel number.
  • 3.1K
  • 02 Dec 2022
Topic Review
Tunneling and Blocking Oxides on Memory Cells
Flash memory is an electronic, non-volatile information storage device that can be electrically erased and reprogrammed. Ideally, the information stored in such a device should be preserved for long when the power is switched off. There are two flash memories designs at present: floating gate and charge trapping. Both of them work by storage of electrical charges in the space above the channel of the MOSFET. The charge storage volume of the flash cell, either poly-Si floating gate or charge trapping dielectric/dielectric stack is confined between blocking and tunnel oxides for electrical insulation from the gate electrode and Si substrate. Blocking and tunnelling oxides are important parts of the flash memory cells, as they affect retention, endurance and program/erase speed performance.
  • 3.1K
  • 20 Oct 2023
Topic Review
Debaryomyces Hansenii in Sausages, Dry-Meat
Debaryomyces hansenii is a hemiascomycetous yeast of undoubted biotechnological importance. It is a heterogeneous yeast species able to grow under extreme conditions, such as high salt or relatively alkaline pH levels. This yeast has high respiratory and low fermentative activity. It ferments with important variations, depending on the strain and growth conditions used. Briefly, some examples of its beneficial effects are the production of xylitol, lipases, and exopeptidases important in the food industry, and of thermophilic β-glucosidases essential to produce fuel alcohol. Debaryomyces hansenii is, most probably, the most abundant yeast found in sausages and dry-meat products manufactured all around the world.
  • 3.1K
  • 04 Aug 2021
Topic Review
Anti-Ro Antibodies and fetal complications
Maternal anti-Ro antibodies present during the fetal period can cause complications ranging from congenital heart block, fetal demise or long-term consequences. The anti-Ro induced autoimmune reaction causes long-term fibrosis and calcification of the conductive tissue. In addition, the CHB injury mechanisms were shown to involve other factors, like fetal susceptibility that increases for every subsequent pregnancy, from a 2% incidence in the case of nulliparous mothers. The predictive value of maternal anti-Ro antibodies for CHB high-risk pregnancy is low, and other markers are lacking, making this condition difficult to efficiently monitor. Moreover, the positive anti-Ro pregnancies do not benefit from a prophylactic treatment or from an efficient therapy once CHB was diagnosed. Thus, new data from ongoing trials are highly expected, to provide both potential biomarkers and therapeutic solutions. This entry illustrates the current understanding of the anti-Ro antibodies associated pathologies, from the perspective of specialists involved in its management, emphasizing key issues, missing links, and possible future directions for an effective interdisciplinary approach.
  • 3.1K
  • 08 Nov 2020
Topic Review
Multiplex Immunohistochemistry/Immunofluorescence (mIHC/IF) Techniques
Multiplex imaging techniques and digital image analysis are powerful tools that could overcome some issues concerning tumour-microenvironment studies. This novel approach to biomarker assessment offers a better understanding of the complicated interactions between tumour cells and their environment. Multiplex labelling enables the detection of multiple markers simultaneously and the exploration of their spatial organisation. 
  • 3.1K
  • 02 Sep 2022
Topic Review
Adverse Possession
Adverse possession, sometimes colloquially described as "squatter's rights",[lower-alpha 1] is a legal principle that applies when a person who does not have legal title to a piece of property—usually land (real property)—attempts to claim legal ownership based upon a history of possession or occupation of the land without the permission of its legal owner. In general, a property owner has the right to recover possession of their property from unauthorized possessors through legal action such as ejectment. However, in the English common law tradition, courts have long ruled that when someone occupies a piece of property without permission and the property's owner does not exercise their right to recover their property for a significant period of time, not only is the original owner prevented from exercising their right to exclude, but an entirely new title to the property springs up in the adverse possessor. In effect, the adverse possessor becomes the property's new owner.[lower-alpha 2] Over time, legislatures have created statutes of limitations that specify the length of time that owners have to recover possession of their property from adverse possessors. In the United States, for example, these time limits vary widely between individual states, ranging from as low as five years to as many as 40 years. Although the elements of an adverse possession action are different in every jurisdiction, a person claiming adverse possession is usually required to prove non-permissive use of the property that is actual, open and notorious, exclusive, adverse, and continuous for the statutory period.[lower-alpha 3] Personal property, traditionally known as "chattel", may also be adversely possessed, but owing to the differences in the nature of real and chattel property, the rules governing such claims are rather more stringent, and favor the legal owner rather than the adverse possessor. Claims for adverse possession of chattel often involve works of art.
  • 3.1K
  • 17 Oct 2022
Topic Review
Modes of Pulsed Laser Ablation in Liquid
Pulsed laser ablation in liquid (PLAL) is a physical and top-down approach used to fabricate nanoparticles (NPs). NPs have better physicochemical properties than their bulk counterparts. 
  • 3.1K
  • 14 Feb 2023
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