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Topic Review
Sample Preparation Techniques Used in Food Analysis
Food samples are complex heterogenous matrices, where all analytes are distributed in a random manner. Food analysis involves sampling, homogenization, and sample preparation that increase the analytical accuracy and precision. Focusing on sample preparation it usually involves storage, particle size reduction, homogenization, weighting, dilution, filtration, extraction, clean-up, and derivatization. Proper sample preparation protocols result in matrix interference elimination and analyte preconcentration, thus affecting the selectivity, sensitivity, detection capability, and the overall performance of an analytical technique. The most time-consuming step in analytical method development is the optimization of the sample preparation protocol that includes analyte extraction and clean-up. Some of the most common sample preparation techniques used in food analysis are liquid-liquid extraction (LLE), solid-liquid extraction (SLE), solid-phase extraction (SPE), solid-phase microextraction (SPME), stir bar sorptive extraction (SBSE), supercritical fluid extraction (SFE), accelerated solvent extraction (ASE), ultrasonic, and Soxhlet extraction.
  • 3.0K
  • 17 Jul 2023
Topic Review
Chrysin
Pharmacological profile of phytochemicals has attracted much attention to their use in disease therapy. Since cancer is a major problem for public health with high mortality and morbidity worldwide, experiments have focused on revealing the anti-tumor activity of natural products. Flavonoids comprise a large family of natural products with different categories. Chrysin is a hydroxylated flavonoid belonging to the flavone category. Chrysin has demonstrated great potential in treating different disorders, due to possessing biological and therapeutic activities, such as antioxidant, anti-inflammatory, hepatoprotective, neuroprotective, etc. Over recent years, the anti-tumor activity of chrysin has been investigated, and in the present review, we provide a mechanistic discussion of the inhibitory effect of chrysin on proliferation and invasion of different cancer cells. Molecular pathways, such as Notch1, microRNAs, signal transducer and activator of transcription 3 (STAT3), nuclear factor-kappaB (NF-κB), PI3K/Akt, MAPK, etc., as targets of chrysin are discussed. The efficiency of chrysin in promoting anti-tumor activity of chemotherapeutic agents and suppressing drug resistance is described. Moreover, poor bioavailability, as one of the drawbacks of chrysin, is improved using various nanocarriers, such as micelles, polymeric nanoparticles, etc. This updated review will provide a direction for further studies in evaluating the anti-tumor activity of chrysin.
  • 3.0K
  • 13 Oct 2020
Topic Review
Equine Piroplasmosis
Equine piroplasmosis (EP), caused by the hemoparasites Theileria equi, Theileria haneyi, and Babesia caballi, is an important tick-borne disease of equines that is prevalent in most parts of the world. Infection may affect animal welfare and has economic impacts related to limitations in horse transport between endemic and non-endemic regions, reduced performance of sport horses and treatment costs.
  • 3.0K
  • 26 Nov 2020
Topic Review
Theranostics
“Theranostics,” a new concept of medical advances featuring a fusion of therapeutic and diagnostic systems, provides promising prospects in personalized medicine, especially cancer. 
  • 3.0K
  • 27 Apr 2021
Topic Review
Non-Mechanical Hybrid Hydrogen Compression
Non-mechanical hybrid hydrogen compressors consists of a first electrochemical compression stage followed by a second one based on the adsorption-desorption of hydrogen on microporous materials. They allow compressing hydrogen up to 70 MPa. Non-mechanical hybrid hydrogen compressors can be a valid alternative to the mechanical compressors. 
  • 3.0K
  • 29 Jun 2020
Topic Review
Molecular Biology of the ERBB2 Signaling Pathway
Notably, 5% of metastatic colorectal cancer (mCRC) cases harbor Erb-B2 receptor tyrosine kinase 2 (ERBB2) alterations. ERBB2, commonly referred to as human epidermal growth factor receptor 2, is a member of the human epidermal growth factor receptor family of protein tyrosine kinases. In addition to being a recognized therapeutic target in the treatment of gastric and breast malignancies, it is considered crucial in the management of colorectal cancer (CRC). 
  • 3.0K
  • 01 Nov 2022
Topic Review
Gearbox Technologies for Tidal Energy Harvesting
Gearboxes are widely used in automobile, aerospace, energy, and process industries and are considered indispensable. Tidal flows always have very low speeds that rarely exceed 5 m/s. Lower tidal speeds result in lower turbine rotation speeds. Therefore, if conventional generators are used to produce electricity, gearboxes are necessary to achieve higher rotor speeds. 
  • 3.0K
  • 26 Dec 2022
Topic Review
IBD
Inflammatory bowel disease (IBD) continue to cause substantial morbidity and massive productivity loss globally. IBD is more common among the productive generation (age group of <30yrs) and affects their quality of life. A single mechanism responsible for IBD is difficult to determine due to the complex interplay of multiple factors including host’s genetic predisposition and environmental factors. The relapsing nature of IBD demands repeated treatment implicating a substantial financial burden to individual patients and the concerned healthcare system, especially in developing nations. This review focuses on the causes of IBD,risk factors, current treatment options and challenges, the role played by the natural products in IBD health care; and situate these natural products within the current biodiscovery research agenda, including the applications of drug discovery techniques and the search for next generation drugs to treat IBD.
  • 3.0K
  • 29 Oct 2020
Topic Review
Dragon 2
Dragon 2 is a class of reusable spacecraft developed and manufactured by U.S. aerospace manufacturer SpaceX, intended as the successor to the Dragon cargo spacecraft. The spacecraft launches atop a Falcon 9 Block 5 rocket and returns via ocean splashdown. When compared to Dragon, Crew Dragon has larger windows, new flight computers and avionics, redesigned solar arrays, and a modified outer mold line. The spacecraft has two planned variants – Crew Dragon, a human-rated capsule capable of carrying up to seven astronauts, and Cargo Dragon, an updated replacement for the original Dragon. Crew Dragon is equipped with an integrated launch escape system in a set of four side-mounted thruster pods with two SuperDraco engines each. Crew Dragon has been contracted to supply the International Space Station (ISS) with crew under the Commercial Crew Program, with the initial award occurring in October 2014 alongside Boeing CST-100 Starliner. Crew Dragon's first non-piloted test flight to the ISS launched in March 2019. Cargo Dragon will supply the ISS with cargo under the Commercial Resupply Services-2 (CRS-2) after a January 2016 selection alongside Northrop Grumman Innovation Systems' Cygnus and Sierra Nevada Corporation's Dream Chaser. SpaceX's first CRS-2 mission with the Cargo Dragon is slated to occur in August 2020 after SpaceX's final CRS-20 mission with the original Dragon spacecraft. The Crew Dragon capsule that flew in the first test flight was scheduled to be used in a flight abort test before it unexpectedly exploded during a test of its SuperDraco engines on 20 April 2019. An investigation into the explosion was completed on 15 July 2019 and resulted in changes to vehicle plumbing. The in-flight abort test was conducted on 19 January 2020 at 15:30 UTC. The first crewed launch is scheduled for April 2020.
  • 3.0K
  • 29 Nov 2022
Topic Review
Tayra
The Tayra (Eira barbara) is a sleek and agile carnivorous mammal native to the forests of Central and South America. Also known as the "tolomuco" or "tolomuco real," this elusive mustelid is characterized by its slender body, dark fur, and a distinctive, bushy tail.
  • 3.0K
  • 08 Feb 2024
Topic Review
Cadmium and Lead Exposure
This entry provides information relevant to public health policy regarding advisable exposure limits for cadmium (Cd) and lead (Pb) that have no biologic role in humans. All of their perceptible effects are toxic. These metals exist in virtually all foodstuffs. Foods which are frequently consumed in large quantities such as cereals, rice, potatoes and vegetables contribute the most to total intake of these metals. Because Cd and Pb exposure are highly prevalent, even a small increase in disease risk can result in a large number of people affected by a disease that is preventable. Public measures to minimize environmental pollution and the food-chain transfer of Cd and Pb are required to prevent Cd- and Pb- related ailments and mortality as are risk reduction measures that set a maximally permissible concentration of Cd and Pb in staple food to the lowest achievable levels.
  • 3.0K
  • 29 Oct 2020
Topic Review
Optical Sensors for Oil/Gas Applications
The sensing requirements of the Oil & Gas industry for improved sensing in deeper zones include increased transmission length, improved spatial coverage and integration of multiple sensors with multimodal sensing capability. This imposes problems like signal attenuation, crosstalks and cross sensitivities. Optical fibre-based sensors are expected to provide superior sensing capabilities compared to traditional electrical sensors. 
  • 3.0K
  • 26 Sep 2021
Topic Review
Methyl Benzoate as Insecticide
The methyl benzoate is an effective pesticide against a range of different agricultural, stored product, and urban insect pests. Methyl benzoate has several important modes of action, including as a contact toxicant, a fumigant, an ovicidal toxin, an oviposition deterrent, a repellent, and an attractant.
  • 3.0K
  • 31 Mar 2022
Topic Review
Oscillatory Spinning Drop Interfacial Rheology
The oscillatory spinning drop method has been proven recently to be an accurate technique to measure dilational interfacial rheological properties. It is the only available equipment for measuring dilational moduli in low interfacial tension systems, as is the case in applications dealing with surfactant-oil-water three-phase behavior like enhanced oil recovery, crude oil dehydration, or extreme microemulsion solubilization. Different systems can be studied with this method with the lower density phase as the spinning drop, i.e, oil-in-water, microemulsion-in-water, oil-in-microemulsion, including systems with the presence of complex natural surfactants like asphaltene aggregates or particles. The technique allows studying the characteristics and properties of water/oil interfaces, particularly when the oil contains asphaltenes and when surfactants are present. We have found that using the oscillating spinning drop method to measure interfacial rheology properties can help make precise measurements in a reasonable amount of time. This is of significance when systems with long equilibration times, e.g., asphaltene or high molecular weight surfactant-containing systems are measured, or with systems formulated with a demulsifier which is generally associated with optimum formulation and a low interfacial tension.
  • 3.0K
  • 08 Sep 2024
Topic Review
First Assistant Engineer
A first assistant engineer (also called the second engineer in some countries) is a licensed member of the engineering department on a merchant vessel. This title is used for the person on a ship responsible for supervising the daily maintenance and operation of the engine department. They report directly to the chief engineer. On a merchant vessel, depending on term usage, "the First" or "the Second" is the marine engineer second in command of the engine department after the ship's chief engineer. Due to the supervisory role this engineer plays, in addition to being responsible for the refrigeration systems, main engines (steam/gas turbine, diesel), and any other equipment not assigned to the Second assistant engineer/third engineer or the Third assistant engineer/fourth engineer(s), he is typically the busiest engineer aboard the ship. If the engine room requires 24/7 attendance and other junior engineers can cover the three watch rotations, the first is usually a "day worker" from 0800-1700, with overtime hours varying according to ship/company. The first assistant/second engineer is usually in charge of preparing the engine room for arrival, departure, or standby and oversees major overhauls on critical equipment.
  • 3.0K
  • 03 Nov 2022
Topic Review
Structure and Function of FSP1
Ferroptosis suppressor protein 1 (FSP1), an NAD(P)H-ubiquinone oxidoreductase that reduces ubiquinone to ubiquinol, has emerged as a critical player in the regulation of ferroptosis. FSP1 operates independently of the canonical system xc–/glutathione peroxidase 4 pathway, making it a promising target for inducing ferroptosis in cancer cells and overcoming ferroptosis resistance.
  • 3.0K
  • 14 Jun 2023
Topic Review
Mechanisms of CYP450 Inhibition
In an ageing society, polypharmacy has become a major public health and economic issue. Overuse of medications, especially in patients with chronic diseases, carries major health risks. One common consequence of polypharmacy is the increased emergence of adverse drug events, mainly from drug–drug interactions. The majority of currently available drugs are metabolized by CYP450 enzymes. Interactions due to shared CYP450-mediated metabolic pathways for two or more drugs are frequent, especially through reversible or irreversible CYP450 inhibition. The magnitude of these interactions depends on several factors, including varying affinity and concentration of substrates, time delay between the administration of the drugs, and mechanisms of CYP450 inhibition. Various types of CYP450 inhibition (competitive, non-competitive, mechanism-based) have been observed clinically, and interactions of these types require a distinct clinical management strategy.
  • 3.0K
  • 17 May 2021
Topic Review
Taylor Manifest Anxiety Scale
The Taylor Manifest Anxiety Scale, often shortened to TMAS, is a test of anxiety as a personality trait, and was created by Janet Taylor in 1953 to identify subjects who would be useful in the study of anxiety disorders. The TMAS originally consisted of 50 true or false questions a person answers by reflecting on themselves, in order to determine their anxiety level. Janet Taylor spent her career in the field of psychology studying anxiety and gender development. Her scale has often been used to separate normal participants from those who would be considered to have pathological anxiety levels. The TMAS has been shown to have high test-retest reliability. The test is for adults but in 1956 a children's form was developed. The test was very popular for many years after its development but is now used infrequently.
  • 3.0K
  • 05 Nov 2022
Topic Review
Near-Infrared Spectrum of Olive Oils
Olive oil is regarded as one of the healthiest food oils due to its high content in triglycerides with unsaturated acids, mainly oleic acid, and its phenolic composition. The analysis of the physico-chemical parameters of quality of olive oil is still carried out in laboratories using chemicals and generating waste, which is relatively costly and time-consuming. Among the various alternatives for the online or on-site measurement of these parameters, the available literature highlights the use of near-infrared spectroscopy (NIRS). 
  • 3.0K
  • 18 Apr 2022
Topic Review
Breakdown Voltages in Different Types of Gases
The idea of using a vacuum as an insulating medium is to take advantage of the fact that when the gas pressure is reduced to a value at which the average free paths of molecules and electrons are greater than the contact gap in the insulating system, the development of electron avalanches that initiate discharges in gases is impossible.
  • 3.0K
  • 07 Sep 2022
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