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Topic Review
Beta-Carotene
β-Carotene is an organic, strongly coloured red-orange pigment abundant in fungi, plants, and fruits. It is a member of the carotenes, which are terpenoids (isoprenoids), synthesized biochemically from eight isoprene units and thus having 40 carbons. Among the carotenes, β-carotene is distinguished by having beta-rings at both ends of the molecule. β-Carotene is biosynthesized from geranylgeranyl pyrophosphate. In some Mucoralean fungi, β-Carotene is a precursor to the synthesis of trisporic acid. β-Carotene is the most common form of carotene in plants. When used as a food coloring, it has the E number E160a.:119 The structure was deduced by Karrer et al. in 1930. In nature, β-carotene is a precursor (inactive form) to vitamin A via the action of beta-carotene 15,15'-monooxygenase. Isolation of β-carotene from fruits abundant in carotenoids is commonly done using column chromatography. It can also be extracted from the beta-carotene rich algae, Dunaliella salina. The separation of β-carotene from the mixture of other carotenoids is based on the polarity of a compound. β-Carotene is a non-polar compound, so it is separated with a non-polar solvent such as hexane. Being highly conjugated, it is deeply colored, and as a hydrocarbon lacking functional groups, it is very lipophilic.
  • 5.8K
  • 16 Nov 2022
Topic Review
Phosphate in Primary Hyperparathyroidism
Serum phosphate is crucial in the management of kidney disease, playing a major role in vascular calcification in chronic kidney failure.  In the past 20 years, the role of phosphate has been profoundly reconsidered since many other molecules have been found to play important roles in phosphate homeostasis, beyond the well-known effect of parathyroid hormone (PTH) or renal function. The advent of new insights into phosphate metabolism must urge the endocrinologist to rethink the pathophysiology of widespread disorders, such as primary hyperparathyroidism.
  • 5.8K
  • 15 Dec 2021
Topic Review
Lattice Materials
Lattice material is a cellular material consisting of a periodic network of structural elements such as rods or beams. This network of lattices exists over a wide spectrum of scale from the nanoscale to macroscale and has been applied in a wide area of applications. In the nanoscale spectrum, most of the CNT (Carbon Nano Tube) based sensors are made using lattice materials. Micro-lattices material is being developed intensively as it offers high energy absorption capability. On a macroscale, due to its high stiffness and lightweight properties, lattice materials are widely used in aerospace applications.
  • 5.8K
  • 28 Mar 2022
Topic Review
Leucine Metabolism
Leucine, an essential branched amino acid, has anti-obesity effects on glucose tolerance, lipid metabolism, and insulin sensitivity. The catabolism of Leucine is a conserved regulator of physiological aging, participating in diverse physiological and pathological processes. This topic review offers an up-to-date report on the decomposition and metabolites of leucine in mammals, as α-ketoisocaproate (KIC) and β-hydroxy-β-methylbutyrate (HMB).
  • 5.8K
  • 29 Oct 2020
Topic Review
Neck (Water Spirit)
The neck, nicor, nokk, nix, nixie, nixy, or nokken (German: Nixe; Dutch: nikker, nekker; Danish: nøkke; Norwegian: nøkken; Swedish: näck; Faroese: nykur; Finnish: näkki; Estonian: näkk) are shapeshifting water spirits in Germanic mythology and folklore who usually appeared in the form of other creatures. Under a variety of names, they were common to the stories of all Germanic peoples, although they are perhaps best known from Scandinavian folklore. The related English knucker was generally depicted as a wyrm or dragon, although more recent versions depict the spirits in other forms. Their sex, bynames, and various transformations vary geographically. The German Nix and his Scandinavian counterparts were male. The German Nixe was a female river mermaid.
  • 5.8K
  • 18 Oct 2022
Topic Review
Axolotl (Ambystoma mexicanum)
The axolotl (Ambystoma mexicanum) is a neotenic amphibian belonging to the family Ambystomatidae, native to the ancient lakes of the Valley of Mexico. Distinguished by its retention of larval traits throughout adulthood, the axolotl exhibits extraordinary regenerative abilities, capable of regenerating limbs, spinal cord, heart, and portions of the brain. Its unique developmental biology and endangered status make it a model organism in evolutionary, genetic, and regenerative studies.
  • 5.8K
  • 10 Oct 2025
Topic Review
Composite Material Applications
Composite materials are composed of two or more different materials having considerably different physical and/or chemical characteristics that, when merged, produce a material with attributes that differ from the separate elements. Composite materials are extensively utilized in the automobile, construction, transportation, aerospace, and renewable energy applications due to their durability, high strength, great quality, minimal maintenance, and low weight.
  • 5.7K
  • 08 Oct 2021
Topic Review
Edible Artemisia: Health Effects
The Artemisia species, often known collectively as "wormwood" are herbs and shrubs, which could be perennial, biennial and annual plants, distributed on all continents except Antarctica, mainly on Northern Hemisphere, with only 25 species on the Southern Hemisphere, being the Asian the zone where higher species diversity is concentrated. The use of Artemisia species in traditional medicine is well-documented and demonstrates the great ethnopharmacological value of this genus. In addition to the traditional medicine applications, Artemisia species exhibit high food value since many of them are species used in culinary as a food, spices, condiments and beverages flavoring.
  • 5.7K
  • 06 Feb 2021
Topic Review
Entrepreneurship in the Sustainable Development Goals
Entrepreneurship plays a prominent and noteworthy role in promoting the Sustainable Development Goals (SDGs). Entrepreneurship, through the creation of new businesses, is recognized as a vital driver in providing employment, reducing inequalities, alleviating poverty, and fostering sustainable growth.
  • 5.7K
  • 18 Feb 2024
Topic Review
Biostimulants
Biostimulants represent a promising type of environment-friendly formulation based on natural products that are frequently used exogenously to enhance abiotic stress tolerance. There is no specific definition of biostimulants yet, despite their regulatory functions in plant growth and development. Biostimulants originate from natural sources and can be effectively categorized into the following four prime groups, namely, acids, microbes, plant-derived bioactive substances, and others.
  • 5.7K
  • 08 Apr 2022
Topic Review
Biological Properties of Flavonoids
It has been reported that nutritional phytochemicals present in fruits, vegetables and cereals, such as flavonoid polyphenolic compounds, can improve bone mineral density by several mechanisms, in addition to having beneficial effects on bone homeostasis and health. In addition to their nutritional properties, flavonoids may have applicability in the manufacture of polymers and can be used as stabilizing agents for biopolyesters, such as polylactide (PLA) and polyhydroxyalkanoate (PHA), which have been widely used in tissue engineering for membranes and scaffolds.
  • 5.7K
  • 11 May 2022
Biography
Hans Albert Einstein
Hans Albert Einstein (/aɪnˈstaɪn, -ˈʃtaɪn/ eyen-STYNE, -⁠SHTYNE; May 14, 1904 – July 26, 1973) was a Swiss-American engineer and educator, the second child and first son of Albert Einstein and Mileva Marić. Hans A. Einstein was a professor of Hydraulic Engineering at the University of California, Berkeley,[1] and was recognized for his research on sediment transport.[2] His papers are
  • 5.7K
  • 27 Dec 2022
Topic Review
AKT and Related Signaling Pathways
Global environmental pollution has led to human exposure to ultraviolet (UV) radiation due to the damaged ozone layer, thereby increasing the incidence and death rate of skin cancer including both melanoma and non-melanoma. Overexpression and activation of V-akt murine thymoma viral oncogene homolog (AKT, also known as protein kinase B) and related signaling pathways are major factors contributing to many cancers including lung cancer, esophageal squamous cell carcinoma and skin cancer. Although BRAF inhibitors are used to treat melanoma, further options are needed due to treatment resistance and poor efficacy. Depletion of AKT expression and activation, and related signaling cascades by its inhibitors, decreases the growth of skin cancer and metastasis. Here we have focused the effects of AKT and related signaling (PI3K/AKT/mTOR) pathways by regulators derived from plants and suggest the need for efficient treatment in skin cancer therapy.
  • 5.7K
  • 28 Sep 2020
Topic Review
Food Security
Food security is a measure of the availability of food and individuals' ability to access it. Affordability is only one factor. There is evidence of food security being a concern many thousands of years ago, with central authorities in ancient China and ancient Egypt being known to release food from storage in times of famine. At the 1974 World Food Conference the term "food security" was defined with an emphasis on supply. They said food security is the "availability at all times of adequate, nourishing, diverse, balanced and moderate world food supplies of basic foodstuffs to sustain a steady expansion of food consumption and to offset fluctuations in production and prices". Later definitions added demand and access issues to the definition. The final report of the 1996 World Food Summit states that food security "exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life." Household food security exists when all members, at all times, have access to enough food for an active, healthy life. Individuals who are food secure do not live in hunger or fear of starvation. Food insecurity, on the other hand, is defined by the United States Department of Agriculture (USDA) as a situation of "limited or uncertain availability of nutritionally adequate and safe foods or limited or uncertain ability to acquire acceptable foods in socially acceptable ways". Food security incorporates a measure of resilience to future disruption or unavailability of critical food supply due to various risk factors including droughts, shipping disruptions, fuel shortages, economic instability, and wars. In the years 2011–2013, an estimated 842 million people were suffering from chronic hunger. The Food and Agriculture Organization of the United Nations, or FAO, identified the four pillars of food security as availability, access, utilization, and stability. The United Nations (UN) recognized the Right to Food in the Declaration of Human Rights in 1948, and has since said that it is vital for the enjoyment of all other rights. The 1996 World Summit on Food Security declared that "food should not be used as an instrument for political and economic pressure".
  • 5.7K
  • 16 Nov 2022
Topic Review
Multilayer Ceramic Capacitors and Its Fabrication Process
The high performance, multi-functionality, and high integration of electronic devices are made possible in large part by the multilayer ceramic capacitors (MLCCs). Due to their low cost, compact size, wide capacitance range, low equivalent series inductance (ESL) and equivalent series resistance (ESR), and excellent frequency response, MLCCs play a significant role in contemporary electronic devices.
  • 5.7K
  • 20 Mar 2023
Topic Review
Sarcopterygii
Sarcopterygii (/ˌsɑːrkɒptəˈrɪdʒi.aɪ/; from grc σάρξ (sárx) 'flesh', and πτέρυξ (ptérux) 'wing, fins')—sometimes considered synonymous with Crossopterygii (from grc κροσσός (krossós) 'fringe')—is a taxon (traditionally a class or subclass) of the bony fishes whose members are known as lobe-finned fishes. The group Tetrapoda, a superclass including amphibians, reptiles (including dinosaurs and therefore birds), and mammals, evolved from certain sarcopterygians; under a cladistic view, tetrapods are themselves considered a group within Sarcopterygii. The known extant non-tetrapod sarcopterygians include two species of coelacanths and six species of lungfishes.
  • 5.7K
  • 27 Oct 2022
Topic Review
Polystyrene vs. Polylactide
Polystyrene (PS) is a thermoplastic polymer made of aromatic hydrocarbon monomer styrene that is derived from fossil-fuels. The synthesis of PS is based on the free radical polymerization of styrene using free-radical initiators. It is mostly used in solid (high impact and general purpose PS), foam and expanded PS forms. The main advantages of PS are low-cost, easy processing ability, and resistance to ethylene oxide, as well as radiation sterilization. Polylactide (PLA)—biodegradable and compostable aliphatic polyester—is one of the key biopolymers with the largest market significance. 
  • 5.7K
  • 28 Dec 2022
Topic Review
Curcumin and Peripheral Neuropathies
Peripheral neuropathies (PN) can be triggered after metabolic diseases, traumatic peripheral nerve injury, genetic mutations, toxic substances, and/or inflammation. PN is a major clinical problem, affecting many patients and with few effective therapeutics. Recently, interest in natural dietary compounds, such as polyphenols, in human health has led to a great deal of research, especially in PN. Curcumin is a polyphenol extracted from the root of Curcuma longa. This molecule has long been used in Asian medicine for its anti-inflammatory, antibacterial, and antioxidant properties. However, like numerous polyphenols, curcumin has a very low bioavailability and a very fast metabolism. This part provides an overview of curcumin in the treatment of PN (anti-inflammatory, antioxidant, anti-endoplasmic reticulum stress (anti-ER-stress), neuroprotection, and glial protection). Finally, because PN are associated with numerous pathologies (e.g., cancers, diabetes, addiction, inflammatory disease...), this part is likely to interest a large audience.
  • 5.7K
  • 20 Oct 2020
Topic Review
Half-Reaction
A half reaction (or half-cell reaction) is either the oxidation or reduction reaction component of a redox reaction. A half reaction is obtained by considering the change in oxidation states of individual substances involved in the redox reaction. Often, the concept of half reactions is used to describe what occurs in an electrochemical cell, such as a Galvanic cell battery. Half reactions can be written to describe both the metal undergoing oxidation (known as the anode) and the metal undergoing reduction (known as the cathode). Half reactions are often used as a method of balancing redox reactions. For oxidation-reduction reactions in acidic conditions, after balancing the atoms and oxidation numbers, one will need to add H+ ions to balance the hydrogen ions in the half reaction. For oxidation-reduction reactions in basic conditions, after balancing the atoms and oxidation numbers, first treat it as an acidic solution and then add OH− ions to balance the H+ ions in the half reactions (which would give H2O).
  • 5.7K
  • 28 Nov 2022
Topic Review
Industrial Heritage in Pakistan
Industrial heritage consists of the remains of industrial culture which are of historical, technological, social, architectural, or scientific value. These remains consist of buildings and machinery, workshops, mills and factories, mines and sites for processing and refining, warehouses and stores, places where energy is generated, transmitted, and used, transport and all its infrastructure, as well as places used for social activities related to the industry, such as housing, religious worship or education. The industrial revolution in Pakistan and the major industrial sites and infrastructure of heritage value, such as seaports and railway infrastructure, can be connected to the British rule of the Indian subcontinent. Unlike industrial sites in the Western world, industrial sites in Pakistan are not recognized as heritage sites and are usually ignored by the authorities. They are not currently considered potential sites for future city redevelopment, and the political instruments to offer new programs for such sites are limited.
  • 5.7K
  • 25 May 2022
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