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Topic Review
Anti-Cancer Properties of Vitamin K
Vitamin K is the common name for a group of compounds recognized as essential for blood clotting. The group comprises phylloquinone (K1)—a 2-methyl-3-phytyl-1,4-naphthoquinone; menaquinone (K2, MK)—a group of compounds with an unsaturated side chain in position 3 of a different number of isoprene units and a 1,4-naphthoquinone group and menadione (K3, MD)—a group of synthetic, water-soluble compounds 2-methyl-1,4-naphthoquinone. However, epidemiological studies suggest that vitamin K has various benefits that go beyond blood coagulation processes. A dietary intake of K1 is inversely associated with the risk of pancreatic cancer, K2 has the potential to induce a differentiation in leukemia cells or apoptosis of various types of cancer cells, and K3 has a documented anti-cancer effect. A healthy diet rich in fruit and vegetables ensures an optimal supply of K1 and K2, though consumers often prefer supplements. Interestingly, the synthetic form of vitamin K—menadione—appears in the cell during the metabolism of phylloquinone and is a precursor of MK-4, a form of vitamin K2 inaccessible in food.
  • 2.0K
  • 11 Nov 2022
Topic Review
Significance of Anthocyanins
Anthocyanins are widespread and biologically active water-soluble phenolic pigments responsible for a wide range of vivid colours, from red (acidic conditions) to purplish blue (basic conditions), present in fruits, vegetables, and coloured grains. 
  • 2.0K
  • 12 Dec 2022
Topic Review
Cement Asphalt Emulsion Mortar Composites
CA mortar (sometimes abbreviated to CAM) is one of the major construction materials for slab ballastless track in high-speed railways; it is an intermediate layer flung within the space between the track slab and the trackbed (as depicted in) of CRTS I and CRTS II. Cement and asphalt mortar is an organic–inorganic composite material primarily composed of asphalt emulsion, cement, sand, water, and other chemical admixtures. This composite material possesses fascinating properties that are different from both concrete and asphalt material alone because it couples the strength of cement as well as the flexibility of asphalt material.
  • 2.0K
  • 03 Nov 2021
Topic Review
Chemical Composition and Biological Activities of Fragaria Genus
Fragaria genus (Rosaceae), commonly known as strawberry, represents one of the most important food plants all over the world, with a double global production compared with all other fruit berries combined. Usually appreciated because of their specific flavor, the strawberries also possess biological properties, including antioxidant, antimicrobial, or anti-inflammatory effects.
  • 2.0K
  • 23 Sep 2022
Topic Review
Sea Buckthorn Active Compounds in Treating Metabolic Syndrome
Sea buckthorn (Hippophae rhamnoides L. or Elaeagnus rhamnoides L.) is a plant that has long been used as a Chinese herbal medicine. This species is known to contain numerous bioactive components, including polyphenols, fatty acids, vitamins, and phytosterols.  In experiments both in vitro and in vivo (ranging from cell lines to animal models and human patients), sea buckthorn has shown positive effects on symptoms of metabolic syndrome; evidence suggests that sea buckthorn treatment can decrease blood lipid content, blood pressure, and blood sugar levels, and regulate key metabolites. 
  • 2.0K
  • 23 May 2023
Topic Review
Cannabinoid Receptors
Spermatogenesis is a highly coordinated process that begins with division of spermatogonia, followed by meiosis to produce haploid spermatids, and finally the differentiation of haploid spermatids into mature spermatozoa. Several stages of male germ cell development are regulated by epigenetic mechanisms that are important for correct gamete development and functions.  The use of  Cannabis sativa has been demonstrated to induce spermatogenesis dysfunctions. Cannabis sativa (Marijuana) exerts its effect by binding to and activating  cannabinoid receptors CB1 and CB2 . In males, both the receptors CB1 and CB2, are involved in male germ cell development.  Here we will discuss on the importance of cannabinoid receptors signaling in the regulation of several stages of male germ cell development and their role in mediating epigenetic modifications that may be transmitted to the next generation by sperm.
  • 2.0K
  • 31 Jul 2020
Topic Review
Resource Curse and Economic Diversification
Economic diversification is an essential aspect of sustainable development as diversification enhances macroeconomic stability and promotes structural and long-term transformation not only in the economy but also in other pillars of development such as social institutions and dimensions. 
  • 2.0K
  • 07 Mar 2022
Topic Review
Climate Change on Himalayan Yak (Bos grunniens)
Climate change is a global issue, with a wide range of ecosystems being affected by changing climatic conditions including the Himalaya. Yak are exquisitely adapted to the high-altitude conditions of the Himalaya and are thus highly likely to be affected by climate change. 
  • 2.0K
  • 07 Sep 2022
Topic Review
Constructed Wetlands as a Sustainable Sanitation Solution
The application of nature-based solutions (NBSs) in treating wastewater are treatment wetlands or constructed wetlands (CW). CWs are natural treatment technologies that efficiently treat many different types of wastewater (domestic wastewater, agricultural wastewater, coal drainage wastewater, petroleum refinery wastewater, compost and landfill leachates, fish-pond discharges, industrial wastewater from pulp and paper mills, textile mills, seafood processing). CWs can effectively treat raw wastewater to different levels of treatments and can be used as a primary, secondary, or tertiary treatment. CWs are engineered systems designed to optimize and copy processes found in natural environments thus they are considered as sustainable, environmentally friendly options for wastewater treatment. CWs have low operational and maintenance requirements and have a stable performance with less vulnerability to inflow variation. CWs have proved their ability to treat several types of wastewaters. Several benefits and facts, such as the low construction and operational costs of CWs, low-energy, and less operational requirements, have raised the interests in CWs as a treatment technology. The sustainability of CWs as a sanitation solution (technical, financial, environmental sustainability) is described with a focus on integrating climate change resilience and a circular economic approach to the technical and financial sustainability.
  • 2.0K
  • 22 Nov 2022
Topic Review
Tulku
A tulku (Tibetan: སྤྲུལ་སྐུ་, Wylie: sprulsku, ZYPY: Zhügu, also tülku, trulku) is a reincarnate custodian of a specific lineage of teachings in Tibetan Buddhism who is given empowerments and trained from a young age by students of his or her predecessor. High-profile examples of tulkus include the Dalai Lamas, the Panchen Lamas, the Samding Dorje Phagmos, the Karmapas, Khyentses, and the Kongtruls.
  • 2.0K
  • 24 Nov 2022
Topic Review
Brainstem Midline Stroke
Most medullary and pontine strokes are sharply marginated and paramedian, with the long axis being oriented in the sagittal plane. This pattern is related to the distribution of the paramedian-penetrating branches arising from the BA and distal VAs, which perforate the paramedian brainstem and never cross the midline. Lateral infarcts, in the distribution of the short circumferential arteries, are seen less frequently than paramedian lesions are. At the midbrain level, midline infarctions can be visualized, as the many involved branches are not limited to a paramedian distribution. Characteristically, brainstem vascular syndromes are also called alternating syndromes due to the presence of crossed neurological signs (ipsilateral cranial nerve signs and contralateral signs of the ascending and descending tracts) which are hallmarks of the brainstem location.
  • 2.0K
  • 06 Feb 2023
Topic Review
Secrets of the Astute Red Fox
An ecosystem’s health is based on a delicate balance between human, nonhuman animal, and environmental health. Any factor that leads to an imbalance in one of the components results in disease. There are several bioindicators that allow people to evaluate the status of ecosystems. The red fox (Vulpes vulpes, Linnaeus, 1758) has the widest world distribution among mammals. It is highly adaptable, lives in rural and urban areas, and has a greatly diverse diet. Being susceptible to environmental pollution and zoonotic agents, red foxes may act as sentinels to detect environmental contaminants, and climatic changes and to prevent and control outbreaks of emerging or re-emerging zoonosis. This entry present the information that is related to the red fox as a sentinel of human, animal, and environmental health.
  • 2.0K
  • 13 Feb 2023
Topic Review
Aquaculture Development in Nigeria
Aquaculture or fish cultivation offers a major source of animal protein and contributes heavily to household diets, livelihood, and economic development in many countries and regions of the world. Nigeria is not left out. In the agricultural sector of the Nigerian economy, aquaculture has been recorded as having the fastest growth rate.
  • 2.0K
  • 11 Dec 2023
Topic Review
Green Extraction Techniques for Bioactive Natural Products
Green extraction techniques represent a paradigm shift in the field of NP extraction, emphasizing sustainability, environmental consciousness, and efficiency. These methods prioritize minimizing the environmental impact associated with traditional extraction processes. Their importance lies in addressing the limitations of conventional techniques, such as low yields, substantial solvent usage, and the risk of degrading heat-sensitive compounds. The benefits of green extraction include enhanced efficiency, reduced solvent consumption, and the preservation of valuable bioactive compounds. Examples of green extraction techniques encompass “supercritical fluid extraction (SFE), subcritical water extraction (SWE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE)”, among others. The significance and advantages of each method contribute to a more sustainable and eco-friendly approach to NP extraction. Detailed discussions on each green extraction technique are provided below, highlighting their unique principles, applications, and advantages in obtaining bioactive natural products.
  • 2.0K
  • 29 Dec 2023
Topic Review
Extreme Microorganisms in the Context of Biogeochemical Nitrogen Cycle
Extreme microorganisms (extremophile) are organisms that inhabit environments characterized by inhospitable parameters for most live beings (extreme temperatures and pH values, high or low ionic strength, pressure, or scarcity of nutrients). To grow optimally under these conditions, extremophiles have evolved molecular adaptations affecting their physiology, metabolism, cell signaling, etc. Due to their peculiarities in terms of physiology and metabolism, they have become good models for (i) understanding the limits of life on Earth, (ii) exploring the possible existence of extraterrestrial life (Astrobiology), or (iii) to look for potential applications in biotechnology. Recent research has revealed that extremophilic microbes play key roles in all biogeochemical cycles on Earth. Nitrogen cycle (N-cycle) is one of the most important biogeochemical cycles in nature; thanks to it, nitrogen is converted into multiple chemical forms, which circulate among atmospheric, terrestrial and aquatic ecosystems. This review summarizes recent knowledge on the role of extreme microorganisms in the N-cycle in extremophilic ecosystems, with special emphasis on members of the Archaea domain. Potential implications of these microbes in global warming and nitrogen balance, as well as their biotechnological applications are also discussed.
  • 2.0K
  • 17 Jun 2020
Topic Review
Ship Handling in Unprotected Waters
In order to implement a new type of escort towing, specially designed to be employed in very adverse weather conditions, considerable changes in the hull form of escort tugs had to be made to improve their stability and performance. Since traditional winch and ropes technologies were only effective in calm waters, tugs had to be fitted with new devices. These improvements allowed the remodeled tugs to counterbalance the strong forces generated by the maneuvers in open waters. This entry presents a review of the new high-performance automatic dynamic winches.
  • 2.0K
  • 26 Mar 2021
Topic Review
Bacteremia
Bacteremia (also bacteraemia) is the presence of bacteria in the blood. Blood is normally a sterile environment, so the detection of bacteria in the blood (most commonly accomplished by blood cultures) is always abnormal. It is distinct from sepsis, which is the host response to the bacteria. Bacteria can enter the bloodstream as a severe complication of infections (like pneumonia or meningitis), during surgery (especially when involving mucous membranes such as the gastrointestinal tract), or due to catheters and other foreign bodies entering the arteries or veins (including during intravenous drug abuse). Transient bacteremia can result after dental procedures or brushing of teeth. Bacteremia can have several important health consequences. The immune response to the bacteria can cause sepsis and septic shock, which has a high mortality rate. Bacteria can also spread via the blood to other parts of the body (which is called hematogenous spread), causing infections away from the original site of infection, such as endocarditis or osteomyelitis. Treatment for bacteremia is with antibiotics, and prevention with antibiotic prophylaxis can be given in high risk situations.
  • 2.0K
  • 10 Oct 2022
Topic Review
Shipworms
The shipworms are marine bivalve molluscs in the family Teredinidae: a group of saltwater clams with long, soft, naked bodies. They are notorious for boring into (and commonly eventually destroying) wood that is immersed in sea water, including such structures as wooden piers, docks and ships; they drill passages by means of a pair of very small shells borne at one end, with which they rasp their way through. Sometimes called "termites of the sea", they also are known as "Teredo worms" or simply Teredo, from the Greek τερηδών teredōn, via Latin. Eventually biologists adopted the common name Teredo as the name for the best-known genus.
  • 2.0K
  • 15 Nov 2022
Topic Review
Asymmetric Synthesis of BINOL Derivatives
The chirality resulting from restricted rotation around a single bond is called atropisomerism (axial chirality). This phenomenon was first described by Christie and Kenner in 1922 when investigating the biaryl 6,6’-dinitro-2,2’-diphenic acid, and the term “atropisomer”, derived from the Greek where “a” means “not” and “tropes” means “turn”, was created by Kuhn. Atropisomers belong to the class of axially chiral compounds; however, here, the enantiomers exist due to restricted rotation around a single bond. Axial chirality has also been considered as an important structural element of many natural products and bioactive compounds, whose enantiomers generally exhibit different pharmacological activities and metabolic processes in vivo and in vitro.
  • 2.0K
  • 10 Jan 2023
Topic Review
Application of Isocyanide-Based Multicomponent Reactions
Multicomponent reactions are a fascinating family of organic chemistry transformations. Traditional bimolecular reactions are outperformed by such reactions, which combine three or more reactants into one reaction product. Multicomponent reactions speed up chemical space exploration by minimizing the quantity of synthesis and refinement steps needed to create a particular target. Isocyanides (isonitriles) were the only stable organic molecules containing a formally divalent carbon atom for a long period of time. The group of isocyanides are distinguishable from other functional groups due to their reactivity.
  • 2.0K
  • 10 May 2023
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