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Topic Review
Feeding Strategy of Dead-Wood Eaters
Decomposition of wood is a very difficult process. Wood is highly resistant to decay, and it’s not very nutritious to boot. It doesn’t provide good sustenance for the decomposers that feed on it – in fact, it may even lack key elements needed for their growth, development and maturation. The only two things it’s abundant in are carbohydrates cellulose and hemicellulose, but they’re simply not enough. Nevertheless, there are daredevils who aren't afraid of starvation and even thrive in the long, dark, winding tunnels dug in dead trees. How is it possible? It’s commonly thought that it’s the symbionts that process the dead wood in order to provide sustenance for saproxylic organisms. However, according to the law of the conservation of mass, this is insufficient because the constituent atoms of nutrients cannot be created by organisms from the available biomass. Therefore, the elemental composition of wood limits the available nutrients, although symbionts are able to increase the digestibility of woody matter and synthesize important organic compounds from nutrients furnished by dead wood. The nutrients required for insects to properly develop are transported to dead wood by fungi, resulting in a rearrangement of the nutritional composition of the wood during the first few years of decay. By consuming decomposed wood that is rich in fungal tissues, the dead wood eater is able to grow, develop and reach maturity.
  • 1.4K
  • 30 Oct 2020
Topic Review
Free Stalls for Dairy Herds
Lying is an important behavior of dairy cattle. Cows should spend more than 50% of a day lying as it has a high impact on their milk yield and animal welfare. The design, size, and flooring properties of the free stalls influence the time cows spend lying, the way they lie down, and their rising movements. The design of the free stalls should enable the cows to move and lie in positions as natural as possible. Cows should rest, with all parts of the body, on a clean, dry and soft bed, be able to stretch their front legs forward, lie on their sides with unobstructed space for their neck and head, and rest with their heads against their flanks without hindrance from a partition. When they stand, they should not be hindered by neck rails, partitions, or supports. A comfortable place for cows to lie down helps cows to stay healthy, improve welfare, and increase milk yield. Hence, the probability of a longer productive life for the cows increases and the number of replacements per year decreases.
  • 1.4K
  • 11 Aug 2021
Topic Review
Crocodile
Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia . The term crocodile is sometimes used even more loosely to include all extant members of the order Crocodilia, which includes the alligators and caimans (family Alligatoridae), the gharial and false gharial (family Gavialidae) among other extinct taxa. Although they appear similar, crocodiles, alligators and the gharial belong to separate biological families. The gharial, with its narrow snout, is easier to distinguish, while morphological differences are more difficult to spot in crocodiles and alligators. The most obvious external differences are visible in the head, with crocodiles having narrower and longer heads, with a more V-shaped than a U-shaped snout compared to alligators and caimans. Another obvious trait is that the upper and lower jaws of the crocodiles are the same width, and the teeth in the lower jaw fall along the edge or outside the upper jaw when the mouth is closed; therefore, all teeth are visible, unlike an alligator, which possesses in the upper jaw small depressions into which the lower teeth fit. Also, when the crocodile's mouth is closed, the large fourth tooth in the lower jaw fits into a constriction in the upper jaw. For hard-to-distinguish specimens, the protruding tooth is the most reliable feature to define the species' family. Crocodiles have more webbing on the toes of the hind feet and can better tolerate saltwater due to specialized salt glands for filtering out salt, which are present, but non-functioning, in alligators. Another trait that separates crocodiles from other crocodilians is their much higher levels of aggression. Crocodile size, morphology, behaviour and ecology differ somewhat among species. However, they have many similarities in these areas as well. All crocodiles are semiaquatic and tend to congregate in freshwater habitats such as rivers, lakes, wetlands and sometimes in brackish water and saltwater. They are carnivorous animals, feeding mostly on vertebrates such as fish, reptiles, birds and mammals, and sometimes on invertebrates such as molluscs and crustaceans, depending on species and age. All crocodiles are tropical species that, unlike alligators, are very sensitive to cold. They separated from other crocodilians during the Eocene epoch, about 55 million years ago. Many species are at the risk of extinction, some being classified as critically endangered.
  • 1.4K
  • 17 Nov 2022
Topic Review
Tissue
In biology, tissue is a biological organizational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues. The English word "tissue" derives from the French word "tissu", the past participle of the verb tisser, "to weave". The study of tissues is known as histology or, in connection with disease, as histopathology. Xavier Bichat is considered as the "Father of Histology". Plant histology is studied in both plant anatomy and physiology. The classical tools for studying tissues are the paraffin block in which tissue is embedded and then sectioned, the histological stain, and the optical microscope. Developments in electron microscopy, immunofluorescence, and the use of frozen tissue-sections have enhanced the detail that can be observed in tissues. With these tools, the classical appearances of tissues can be examined in health and disease, enabling considerable refinement of medical diagnosis and prognosis.
  • 1.4K
  • 26 Oct 2022
Topic Review
New Insights into Melanocytes Beyond Conventional Recognition
Melanocytes produce melanin to protect the skin from UV-B radiation. Notwithstanding, the spectrum of their functions extends far beyond their well-known role as melanin production factories. Melanocytes have been considered as sensory and computational cells. The neurotransmitters, neuropeptides, and other hormones produced by melanocytes make them part of the skin’s well-orchestrated and complex neuroendocrine network, counteracting environmental stressors. Melanocytes can also actively mediate the epidermal immune response. Melanocytes are equipped with ectopic sensory systems similar to the eye and nose and can sense light and odor.In addition, melanocytes have also been shown to be localized in internal sites such as the inner ear, brain, and heart, locations not stimulated by sunlight.
  • 1.4K
  • 18 Jul 2022
Topic Review
Actinopterygii
Actinopterygii (/ˌæktɪnɒptəˈrɪdʒiaɪ/; from actino- 'having rays', and grc πτέρυξ (ptérux) 'wing, fins'), members of which are known as ray-finned fishes, is a clade (traditionally class or subclass) of the bony fishes. They comprise over 50% of living vertebrate species. The ray-finned fishes are so-called because their fins are webs of skin supported by bony or horny spines (rays), as opposed to the fleshy, lobed fins that characterize the class Sarcopterygii (lobe-finned fish). These actinopterygian fin rays attach directly to the proximal or basal skeletal elements, the radials, which represent the link or connection between these fins and the internal skeleton (e.g., pelvic and pectoral girdles). By species count, actinopterygians dominate the vertebrates, and they comprise nearly 99% of the over 30,000 species of fish. They are ubiquitous throughout freshwater and marine environments from the deep sea to the highest mountain streams. Extant species can range in size from Paedocypris, at 8 mm (0.3 in), to the massive ocean sunfish, at 2,300 kg (5,070 lb), and the long-bodied oarfish, at 11 m (36 ft). The vast majority of Actinopterygii (~95%) are teleosts.
  • 1.4K
  • 27 Oct 2022
Topic Review
Cytogenetics of Myelodysplastic Syndrome
Myelodysplastic syndromes (MDS) are heterogeneous groups of clonal myeloid disorders characterized by unexplained persistent peripheral blood (PB) cytopenia(s) of one or more of the hematopoietic lineages, or bone marrow (BM) morphologic dysplasia in hematopoietic cells, recurrent genetic abnormalities, and an increased risk of progression to acute myeloid leukemia (AML). Cytogenetics has been an important and a necessary parameter in the diagnosis of MDS. The WHO relies heavily on cytogenetic aberrations in MDS. In addition to establishing a clonal process in patients with peripheral blood cytopenia, cytogenetics plays a major role in the prognostication, clinical-morphologic correlation, theragnostic strategies, and in predicting the likelihood of progression to AML. In contrast to other myeloid malignancies, in which the diagnosis is defined by a single cytogenetic event, there is a vast spectrum of cytogenetic-defining lesions in MDS, making diagnosis very challenging. 
  • 1.4K
  • 08 Jul 2022
Topic Review
Myokines
Myokines are small proteins (5–20 kDa) and proteoglycan peptides that are produced and secreted by skeletal muscle cells in response to muscle contractions.
  • 1.4K
  • 14 Oct 2020
Topic Review
PLBs organogenesis in orchid
A protocorm-like structure those are generated from the vegetative explant in vitro, are known as protocorm like body (PLB). For the mass propagation of plant, PLBs regeneration is one of the key focusing. Orchid is the largest genus of the flowering plants and they have number of commercially important genus. Orchids are difficult to propagate by seeds and vegetative propagation methods. In vitro propagation is the most efficient technique for the orchid propagation. Induction and proliferation of PLBs can accelerate their propagation by reduce the time and costs. It is possible to propagate numerous numbers of plants within short period of time with low costs from PLBs. Researchers are trying to develop efficient PLBs induction and proliferation techniques using different plant growth regulators, carbon sources, and light emitting diodes. Here, we are discussing about the progress of the PLBs organogenesis in orchids.
  • 1.4K
  • 13 Jan 2021
Topic Review
Anti-Cancer Quinone
Natural quinones are secondary metabolites of plant and are categorized as benzoquinone, naphthoquinone, phenanthrenequinone, and anthraquinone according to their aromatic carbon skeleton [3]. Quinones are highly electrophilic molecules that accept one- or two-electrons from flavoenzymes and iron-sulfur proteins to form semiquinone or hydroquinone. They exert cytotoxic effects through alkylating proteins or DNA and affect the redox cycle with their semiquinone radicals to generate reactive oxygen species.
  • 1.4K
  • 27 Oct 2020
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