സമുദ്ര, സമുദ്രതീര ജീവികൾ

സമുദ്ര, സമുദ്രതീര ജീവിക

Atmospheric dispersion corrector for a multi-object spectroscopic mode of HROS-TMT

Highly multiplexed spectroscopic surveys have changed the astronomy landscape in recent years. However, these surveys are limited to low and medium spectral resolution. High spectral resolution spectroscopy is often photon starved and will benefit from a large telescope aperture. Multiplexed high-resolution surveys require a wide field of view and a large aperture for a suitable large number of bright targets. This requirement introduces several practical difficulties, especially for large telescopes, such as the future ELTs. Some of the challenges are the need for a wide field atmospheric dispersion corrector and to deal with the curved non-telecentric focal plane. Here, we present a concept of Multi-Object Spectroscopy (MOS) mode for TMT High-Resolution Optical Spectrograph (HROS), we have designed an atmospheric dispersion corrector for individual objects that fit inside a fiber positioner. We present the ZEMAX design and the performance of the atmospheric dispersion corrector for all elevations accessible by TMT

IMPACT OF BIG DATA AND EMERGING RESEARCH TRENDS

The term big data is extensively used in many computational and decision making domains. Big data is nothing but the large data sets formed from various sources and are almost impossible to process and analyse using traditional approaches because of its complexity. Efficient analysis and processing of big data within a given time frame is essential for it to be useful. Various technologies like Hadoop, MapReduce, etc. are used to analyse the big data and hence possible to retrieve knowledge from the large datasets. This paper focuses on the impact of big data, the technologies in big data processing and its limitations and the emerging trends in big data

Coconut-growing soils of Kerala: 1. Characteristics and classification

Coconut plantations are the major land use systems in Kerala state. The tropical hot humid climate and soils of the state are considered suitable for the palm, with the exception of highlands occurring 600 m above MSL. However, the productivity of coconut is abysmally low in the state with an average productivity of around 40 nuts per year per palm. To find out whether the highly weathered and leached low activity clay soils developed in tropical hot humid climate is responsible for the low yield, an assessment of soil qualities in the coconut-growing soils of the state was made. Six distinct regions of coconut cultivation in the state were identified and delineated based on the variability of agro-climate and soils, viz., Central and Eastern Palakkad, Northern Kerala, Central Kerala, Southern Kerala, Onattukara sandy plains and coastal sandy plains. Soil profiles were studied at representative sites in each region. Investigated morphological features and sampled horizon-wise for the analysis of physical and chemical properties of the soil. Coconut-growing soils of Kerala state are in general deep and well drained, clayey or sandy having good structure permitting rapid transmission of water. The soils of Palakkad, Southern Kerala and Coastal Sandy Plains have near neutral reaction whereas the extensive areas of laterite soils of Northern and Central Kerala and sandy soils of Onattukara were strongly acid and had high levels of KCl extractable aluminium. The acid soils also analysed for low levels of basic cations, potassium, calcium and magnesium. Soils from all regions except Palakkad have low CEC. Surface and sub-soils base status were extremely low for soils of Northern and Central Kerala and Onattukara sandy plain. The soils of Central and Eastern Palakkad were classified as Typic Haplustalfs, Northern Kerala as Plinthic Humults, Central Kerala as Typic Plinthustults, Southern Kerala as Rhodic Kandiustults and the soils of sandy plains as Ustipsamments, according to soil taxonomy

Essential oils as valuable feed additive: A narrative review of the state of knowledge about their beneficial health applications and enhancement of production performances in poultry

New research has begun to develop safe and effective alternatives to feed-antibiotics as growth enhancers in response to mounting pressure on the poultry sector to do so. There is a significant demand for poultry products all across the world right now. To achieve this goal, key performance indicators are optimized, such as the rate of chicken growth, the amount of feed used, and the health of the flock as a whole. As a result of this growing need, various alternatives to antibiotics have entered the market. New approaches are desperately needed to keep poultry productivity and efficiency at a high level in the face of mounting pressure to limit the use of antibiotics. Recent years have seen an uptick in interest in the potential of aromatic plant extracts as growth and health boosters in poultry. The great majority of plants' positive effects are accounted for by essential oils (EOs) and other secondary metabolites. EOs have been proven to promote digestive secretion production, improve blood circulation, exert antioxidant qualities, reduce levels of dangerous microbes, and maybe improve the immune status of poultry. EOs are often believed to be safe, non-toxic alternatives because they are all-natural, chemical-free, and devoid of potentially harmful deposits. EOs are extracted from plants, and while there are thousands of them, only approximately 300 have been deemed to have significant commercial value. Many different types of bacteria, viruses, fungi, and parasites are negatively affected by EOs in multiple studies conducted both in vitro and in vivo. The review covers the fundamentals of EOs, their anti-oxidant and immunomodulatory capabilities, their growth-promoting benefits, and their effectiveness against numerous diseases in poultry

Farnesoid X Receptor and its ligands inhibit the function of platelets

Objective - While initially seemingly paradoxical due to the lack of nucleus, platelets possess a number of transcription factors that regulate their function through DNA-independent mechanisms. These include the Farnesoid X Receptor (FXR), a member of the superfamily of ligand-activated transcription factors that has been identified as a bile acid receptor. In this study, we show that FXR is present in human platelets and FXR ligands, GW4064 and 6-ECDCA, modulate platelet activation nongenomically. Approach and Results - FXR ligands inhibited the activation of platelets in response to stimulation of collagen or thrombin receptors, resulting in diminished intracellular calcium mobilization and secretion, fibrinogen binding and aggregation. Exposure to FXR ligands also reduced integrin alphaIIbbeta3 outside-in signaling and thereby reduced the ability of platelets to spread and to stimulate clot retraction. FXR function in platelets was found to be associated with the modulation of cGMP levels in platelets and associated downstream inhibitory signaling. Platelets from FXR-deficient mice were refractory to the actions of FXR agonists on platelet function and cyclic nucleotide signaling, firmly linking the non-genomic actions of these ligands to the FXR receptor. Conclusion – This study provides support for the ability of FXR ligands to modulate platelet activation. The athero-protective effects of GW4064, with its novel antiplatelet effects, indicate FXR as a potential target for prevention of athero-thrombotic disease

Biodiversity of sponges (Phylum: Porifera) off Tuticorin, India

The present study deals with 18 new records of sponges found at Kayalpatnam area and a checklist of sponges reported off Tuticorin in the Gulf of Mannar. The new records are Aiolochoria crassa, Axinella damicornis, Clathria (Clathria) prolifera, Clathrina sororcula, Clathrina sinusarabica, Clathrina coriacea, Cliona delitrix, Colospongia auris, Crella incrustans, Crambe crambe, Hyattella pertusa, Plakortis simplex, Petrosia (Petrosia) ficiformis, Phorbas plumosus, Spheciospongia vesparium, Spirastrella cunctatrix, Xestospongia muta and Sycon ciliatum. Details about the species diversity of common sponges, invasive sponges,massive sponges and boring sponges of the area are discussed and presented

Human BCAS3 Expression in Embryonic Stem Cells and Vascular Precursors Suggests a Role in Human Embryogenesis and Tumor Angiogenesis

Cancer is often associated with multiple and progressive genetic alterations in genes that are important for normal development. BCAS3 (Breast Cancer Amplified Sequence 3) is a gene of unknown function on human chromosome 17q23, a region associated with breakpoints of several neoplasms. The normal expression pattern of BCAS3 has not been studied, though it is implicated in breast cancer progression. Rudhira, a murine WD40 domain protein that is 98% identical to BCAS3 is expressed in embryonic stem (ES) cells, erythropoiesis and angiogenesis. This suggests that BCAS3 expression also may not be restricted to mammary tissue and may have important roles in other normal as well as malignant tissues. We show that BCAS3 is also expressed in human ES cells and during their differentiation into blood vascular precursors. We find that BCAS3 is aberrantly expressed in malignant human brain lesions. In glioblastoma, hemangiopericytoma and brain abscess we note high levels of BCAS3 expression in tumor cells and some blood vessels. BCAS3 may be associated with multiple cancerous and rapidly proliferating cells and hence the expression, function and regulation of this gene merits further investigation. We suggest that BCAS3 is mis-expressed in brain tumors and could serve as a human ES cell and tumor marker

Sponge fauna of the Lakshadweep Islands of Indian Ocean

The present study deals with four new records of sponges found at Lakshadweep area and a checklist of sponges reported off. The new records are Agelas oroides, Callyspongia (Cladochalina) aculeata, Raspailia (Clathriodendron) arbuscula and Stylissa massa. Details about the species diversity of common sponges, massive sponges, boring sponges of the area are discussed and presented

RETRACTED ARTICLE: Age-dependent Increase in Desmosterol Restores DRM Formation and Membrane-related Functions in Cholesterol-free DHCR24−/− Mice

Cholesterol is a prominent modulator of the integrity and functional activity of physiological membranes and the most abundant sterol in the mammalian brain. DHCR24-knock-out mice lack cholesterol and accumulate desmosterol with age. Here we demonstrate that brain cholesterol deficiency in 3-week-old DHCR24−/− mice was associated with altered membrane composition including disrupted detergent-resistant membrane domain (DRM) structure. Furthermore, membrane-related functions differed extensively in the brains of these mice, resulting in lower plasmin activity, decreased β-secretase activity and diminished Aβ generation. Age-dependent accumulation and integration of desmosterol in brain membranes of 16-week-old DHCR24−/− mice led to the formation of desmosterol-containing DRMs and rescued the observed membrane-related functional deficits. Our data provide evidence that an alternate sterol, desmosterol, can facilitate processes that are normally cholesterol-dependent including formation of DRMs from mouse brain extracts, membrane receptor ligand binding and activation, and regulation of membrane protein proteolytic activity. These data indicate that desmosterol can replace cholesterol in membrane-related functions in the DHCR24−/− mouse