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Topic Review
Arthropoda
Arthropods (/ˈɑːrθrəpɒd/, from grc ἄρθρον (arthron) 'joint', and πούς (pous) 'foot' (gen. ποδός)) are invertebrate animals having an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior organs; it has an open circulatory system. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is "ladder-like", with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fusion of the ganglia of these segments and encircle the esophagus. The respiratory and excretory systems of arthropods vary, depending as much on their environment as on the subphylum to which they belong. Arthropods use combinations of compound eyes and pigment-pit ocelli for vision. In most species, the ocelli can only detect the direction from which light is coming, and the compound eyes are the main source of information, but the main eyes of spiders are ocelli that can form images and, in a few cases, can swivel to track prey. Arthropods also have a wide range of chemical and mechanical sensors, mostly based on modifications of the many bristles known as setae that project through their cuticles. Similarly, their reproduction and development are varied; all terrestrial species use internal fertilization, but this is sometimes by indirect transfer of the sperm via an appendage or the ground, rather than by direct injection. Aquatic species use either internal or external fertilization. Almost all arthropods lay eggs, but many species give birth to live young after the eggs have hatched inside the mother, and a few are genuinely viviparous, such as aphids. Arthropod hatchlings vary from miniature adults to grubs and caterpillars that lack jointed limbs and eventually undergo a total metamorphosis to produce the adult form. The level of maternal care for hatchlings varies from nonexistent to the prolonged care provided by social insects. The evolutionary ancestry of arthropods dates back to the Cambrian period. The group is generally regarded as monophyletic, and many analyses support the placement of arthropods with cycloneuralians (or their constituent clades) in a superphylum Ecdysozoa. Overall, however, the basal relationships of animals are not yet well resolved. Likewise, the relationships between various arthropod groups are still actively debated. Today, Arthropods contribute to the human food supply both directly as food, and more importantly, indirectly as pollinators of crops. Some species are known to spread severe disease to humans, livestock, and crops.
  • 1.4K
  • 10 Nov 2022
Topic Review
Exogenous Organic Matter Amendments
Exogenous organic matter (EOM) is defined as the whole of the OM that is introduced into the soil in order to improve its fertility, quality and the potential of the land for non-agricultural use. EOM includes a very wide range of biowastes from various sources.
  • 1.4K
  • 30 Oct 2020
Topic Review
Vitamin D Scarcity in Arctic and  Tropical Peoples
Vitamin D metabolism differs among human populations because the species has adapted to different natural and cultural environments. Two environments are particularly difficult for the production of vitamin D by the skin: the Arctic, where the skin receives little solar UVB over the year; and the Tropics, where the skin is highly melanized and blocks UVB. In both cases, natural selection has favored the survival of those individuals who use vitamin D more efficiently or have some kind of workaround that ensures sufficient uptake of calcium and other essential minerals from food passing through the intestines. Vitamin D scarcity has either cultural or genetic solutions. Cultural solutions include consumption of meat in a raw or boiled state and extended breastfeeding of children. Genetic solutions include higher uptake of calcium from the intestines, higher rate of conversion of vitamin D to its most active form, stronger binding of vitamin D to carrier proteins in the bloodstream, and greater use of alternative metabolic pathways for calcium uptake. Because their bodies use vitamin D more sparingly, indigenous Arctic and Tropical peoples can be misdiagnosed with vitamin D deficiency and wrongly prescribed dietary supplements that may push their vitamin D level over the threshold of toxicity.
  • 1.4K
  • 20 Oct 2022
Topic Review
Composition of Nuts
The possibility that nut intake may defend human health is an interesting point of view and has been investigated worldwide. Consequently, nuts are commonly promoted as healthy. The number of investigations proposing a correlation between nut consumption and a decrease in the risk of key chronic diseases has continued to increase. Nuts are a source of intake of fiber, and dietary fiber is associated with a reduced occurrence of obesity and cardiovascular diseases. Nuts likewise provide minerals and vitamins to the diet and supply phytochemicals that function as antioxidant, anti-inflammatory, and phytoestrogens agents and other protective mechanisms. 
  • 1.3K
  • 13 Mar 2023
Topic Review
FBLN5 Gene
Fibulin 5: The FBLN5 gene provides instructions for making a protein called fibulin-5. 
  • 1.3K
  • 25 Dec 2020
Topic Review
Ecological Succession Theory
In addition to states of space that are supposedly to be aspired to or maintained, which are often the subject of heated, acrimonious debates, there are temporary states of equilibrium in time that mirror the overarching cycle of life, have been the subject of research for a very long time, and are well documented and conceptually understood: namely, ecological succession. The knowledge and understanding of succession is irreplaceable to have a chance today to ground and resolve such mentioned debates about multiple claims and uses of spaces nowadays. For example, a main challenge of the current time is that large areas of land are needed for renewable energy production, and production sites should be designed to include biodiversity preservation. Decision-makers need guidance for reasonable coexistence. Succession theory can indeed provide substantial background and guidance.
  • 1.3K
  • 27 Jun 2022
Topic Review
Salvia hispanica and Salviae hispanicae semen
Salvia hispanica L. is a plant species that has been used since antiquity and is now highly valued for its unique nutritional and potential medicinal properties. Chia seeds have recently become one of the most popular food ingredients, with a number of beneficial effects on the functioning of the human body. The data presented under our review indicate that they are also a valuable health-promoting dietary supplement as well as cosmetic ingredient. Scientific studies on pharmacological activities of chia seeds proved their potential valuable role in the prevention of diseases which currently are considered a global health problem. The research confirmed the cardioprotective, antihypertensive, antidiabetic, antiatherosclerotic, nephroprotective, anti-inflammatory, as well as antioxidant properties.
  • 1.3K
  • 16 Feb 2022
Topic Review
Irisin and Incretin Hormones
Incretins are gut hormones that potentiate glucose-stimulated insulin secretion (GSIS) after meals. Glucagon-like peptide-1 (GLP-1) is the most investigated incretin hormone, synthesized mainly by L cells in the lower gut tract. GLP-1 promotes β-cell function and survival and exerts beneficial effects in different organs and tissues. Irisin, a myokine released in response to a high-fat diet and exercise, enhances GSIS. Similar to GLP-1, irisin augments insulin biosynthesis and promotes accrual of β-cell functional mass. In addition, irisin and GLP-1 share comparable pleiotropic effects and activate similar intracellular pathways. The insulinotropic and extra-pancreatic effects of GLP-1 are reduced in type 2 diabetes (T2D) patients but preserved at pharmacological doses. GLP-1 receptor agonists (GLP-1RAs) are therefore among the most widely used antidiabetes drugs, also considered for their cardiovascular benefits and ability to promote weight loss. Irisin levels are lower in T2D patients, and in diabetic and/or obese animal models irisin administration improves glycemic control and promotes weight loss. This review aims to describe the similarities between GLP-1 and irisin and to propose a new potential axis involving the gut, muscle, and endocrine pancreas that controls energy homeostasis.
  • 1.3K
  • 10 Mar 2021
Topic Review
Hybrid Rye Breeding and Production
Hybrid rye breeding leads to considerably higher grain yield and a higher revenue to the farmer. The basis of hybrid seed production is the CMS-inducing Pampa (P) cytoplasm derived from an Argentinean landrace and restorer-to-fertility (Rf) genes. Breeding is based on inbred line development and intensive testing for line per se performance and general combining ability (GCA). The finally selected inbred lines are used to compose a topcross hybrid with two genetically different seed parent lines (A-P, B-N) and a restorer synthetic composed of two S2 lines (SynRf). European restorer sources show low-to-moderate pollen-fertility levels. This results in higher susceptibility to ergot (Claviceps purpurea) because rye pollen and ergot spores are in strong competition for the unfertilized stigma. Rf genes from non-adapted Iranian primitive rye and old Argentinean cultivars proved to be most effective. The major Rf gene in these sources was localized on chromosome 4RL, which is also a hotspot of restoration in other Triticeae. Commercial hybrids with these Rf genes showed a similar low ergot infection when compared with population cultivars. The great future challenges of climate change, such as increased drought stress tolerance, improved lodging tolerance, as well as the increasing need for resistant varieties can effectively only be met by hybrid breeding.
  • 1.3K
  • 06 May 2022
Topic Review
Pathophysiology of Cerebral Malaria and Treatment
Plasmodium falciparum causes over 90 percent of all malaria infections. Children under the age of 5 years and pregnant women were the most susceptible groups affected by malaria. The World Health Organization (WHO) has characterized malaria as severe and uncomplicated. Delays in the detection and treatment of an uncomplicated infection of P. falciparum malaria lead to complications of severe cerebral malaria (CM). CM is usually caused by P. falciparum, but Plasmodium vivax is rarely responsible for CM complications. CM is a severe neurological complication caused by Plasmodium falciparum infection, resulting in high mortality rates. CM is characterized by brain tissue hemorrhage, the accumulation of infected red blood cells and mononuclear cells in brain microvessels, and blood-brain barrier (BBB) disruption. 
  • 1.3K
  • 11 Jul 2022
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