218 research outputs found

    Occurrence of Similar Periods in Geomagnetic Field Variations and Solar Activity

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    The periodicities associated with some geomagnetic field parameters under quiet and disturbed solar conditions have been examined using a set of data spanning through five years obtained courtesy of INTERMAGNET network. Hourly values of the Horizontal component of the geomagnetic field simultaneously obtained at seven INTERMAGNET stations were engaged in the study. The stations were well distributed across the latitudes, viz: Bangui, 4.4°N; Kourou, 5.1°N; Alibag, 18.6°N; San Juan18.1°N; Crozet, 46.4°S; Barrow, 71.3°N; Scott  Base, 77.9°S). Solar quiet daily variation Sq, Superposed Magnetic field SPMF and Solar disturbance daily variation SD in the horizontal magnetic field component were evaluated and studied for their spectral characteristics. The spectral analysis revealed the periods of 6 hours, 12 hours, 24 hours, 3 months, 6 months, 12 months and 16 months in the geomagnetic field variations. The observed periodicities were explained in terms of associated solar terrestrial processes. This clearly shows the influence of an extra terrestrial source (the Sun) on terrestrial processes. Sun is the undisputable driver of space weathe

    DNA damage response at telomeres boosts the transcription of SARS-CoV-2 receptor ACE2 during aging

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    The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the coronavirus disease 2019 (COVID-19), known to be more common in the elderly, who also show more severe symptoms and are at higher risk of hospitalization and death. Here, we show that the expression of the angiotensin converting enzyme 2 (ACE2), the SARS-CoV-2 cell receptor, increases during aging in mouse and human lungs. ACE2 expression increases upon telomere shortening or dysfunction in both cultured mammalian cells and in vivo in mice. This increase is controlled at the transcriptional level, and Ace2 promoter activity is DNA damage response (DDR)-dependent. Both pharmacological global DDR inhibition of ATM kinase activity and selective telomeric DDR inhibition by the use of antisense oligonucleotides prevent Ace2 upregulation following telomere damage in cultured cells and in mice. We propose that during aging telomere dysfunction due to telomeric shortening or damage triggers DDR activation and this causes the upregulation of ACE2, the SARS-CoV-2 cell receptor, thus contributing to make the elderly more susceptible to the infection

    CARCASS INDICES AND MEAT QUALITY OF BROILER CHICKENS FED DIETS CONTAINING FORTIFIED FERMENTED CASSAVA STUMP

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    A 56-day study was conducted to evaluate carcass and meat quality of broiler chickens fed diets containing fortified fermented cassava stump (FFCS) as a replacement for maize. Cassava stumps and leaves were fermented in the solid state at room temperature, using Aspergillus niger ATCC 16404 for 192 and 96 hours, respectively, and then mixed at a ratio of 19:1 to obtain the FFCS. The birds were allotted into four treatments with three replicates (n= 30). The treatments consistzzed of different inclusion levels of FFCS: Diet 1 containing 0% FFCS (control treatment); Diet 2 containing 20% FFCS; Diet 3 containing 40% FFCS; and Diet 4 containing 60% FFCS. Dressing and eviscerated percentages were higher (p 0.05) by the inclusion of FFCS, but values obtained were higher with up to 40%. Meat quality was significantly (p < 0.05) influenced by the FFCS. In addition, the degree of meat peroxidation decreased with increased FFCS levels. Diets with up to 40% FFCS inclusion resulted in improved carcass traits, oxidative stability, and meat quality. Therefore, the addition of fortified cassava stump in broiler chickens' diets could produce meat of better quality, with low peroxidation, high oxidative stability, and longer shelf-life.z

    Morpheus Reveals Distant Disk Galaxy Morphologies with JWST: The First AI/ML Analysis of JWST Images

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    The dramatic first images with JWST demonstrated its power to provide unprecedented spatial detail for galaxies in the high-redshift universe. Here, we leverage the resolution and depth of the JWST Cosmic Evolution Early Release Science Survey data in the Extended Groth Strip to perform pixel-level morphological classifications of galaxies in JWST F150W imaging using the Morpheus deep-learning framework for astronomical image analysis. By cross-referencing with existing photometric redshift catalogs from the Hubble Space Telescope (HST) CANDELS survey, we show that JWST images indicate the emergence of disk morphologies before z ∼ 2 and with candidates appearing as early as z ∼ 5. By modeling the light profile of each object and accounting for the JWST point-spread function, we find the high-redshift disk candidates have exponential surface brightness profiles with an average Sérsic index 〈n〉 = 1.04 and &gt;90% displaying “disky” profiles (n &lt; 2). Comparing with prior Morpheus classifications in CANDELS we find that a plurality of JWST disk galaxy candidates were previously classified as compact based on the shallower HST imagery, indicating that the improved optical quality and depth of the JWST helps to reveal disk morphologies that were hiding in the noise. We discuss the implications of these early disk candidates on theories for cosmological disk galaxy formation

    Antioxidant status, hematology, performance, organ and carcass evaluation of heat_stressed broiler chickens fed with dietary Bambusa vulgaris leaf meal

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    Objectives: The objective of this study was to evaluate the inclusion of bamboo leaf meal (BLM) in broiler chicken feed to alleviate heat stress. Materials and Methods: This investigation was conducted following institutional policies guiding the handling of animals as approved for scientific research. 150 heat-stressed Arbor Acres broiler chickens were divided randomly into five dietary treatments, T1–T5, of 30 per treatment and 10 per replicate, to determine the consequence of feeding BLM on health and performance. Birds in T1–T4 were fed 0%, 1%, 1.5%, and 2% BLM-included diets, respectively, while T5 had a 0.2% vitamin C-included diet. Results: Increasing dietary BLM positively impacted body weight gain, feed intake, feed conver�sion rate (FCR), and stress indices levels. Broiler chickens had better feed intake (267 gm), weight gain (1,504 gm), and FCR (3.64) in T4. Serum glutathione peroxidase and malondialdehyde levels were not statistically different with increasing dietary BLM, while corticosterone levels were lower for chickens fed with dietary BLM. The superoxide dismutase index levels did not follow a particu�lar pattern as dietary BLM increased. The hematology, carcass, and organ quality were unaffected by dietary BLM inclusion. Conclusion: BLM inclusions up to 2% in the broiler diet ameliorate heat stress conditions and improve performance without imposing any detrimental impact on the birds

    Development of paediatric non-stage prognosticator guidelines for population-based cancer registries and updates to the 2014 Toronto Paediatric Cancer Stage Guidelines

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    Population-based cancer registries (PBCRs) generate measures of cancer incidence and survival that are essential for cancer surveillance, research, and cancer control strategies. In 2014, the Toronto Paediatric Cancer Stage Guidelines were developed to standardise how PBCRs collect data on the stage at diagnosis for childhood cancer cases. These guidelines have been implemented in multiple jurisdictions worldwide to facilitate international comparative studies of incidence and outcome. Robust stratification by risk also requires data on key non-stage prognosticators (NSPs). Key experts and stakeholders used a modified Delphi approach to establish principles guiding paediatric cancer NSP data collection. With the use of these principles, recommendations were made on which NSPs should be collected for the major malignancies in children. The 2014 Toronto Stage Guidelines were also reviewed and updated where necessary. Wide adoption of the resultant Paediatric NSP Guidelines and updated Toronto Stage Guidelines will enhance the harmonisation and use of childhood cancer data provided by PBCRs

    Efficiency of siRNA delivery by lipid nanoparticles is limited by endocytic recycling

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    Despite substantial efforts to understand the interactions between nanoparticles and cells, the cellular processes that determine the efficiency of intracellular drug delivery remain largely unclear. Here we examined cellular uptake of siRNA delivered in lipid nanoparticles (LNPs) using cellular trafficking probes in combination with automated high-throughput confocal microscopy as well as defined perturbations of cellular pathways paired with systems biology approaches to uncover protein-protein and protein-small molecule interactions. We show that multiple cell signaling effectors are required for initial cellular entry of LNPs through macropinocytosis, including proton pumps, mTOR, and cathepsins. SiRNA delivery is substantially reduced as ≅70% of the internalized siRNA undergoes exocytosis through egress of LNPs from late endosomes/lysosomes. Niemann Pick type C1 (NPC1) is shown to be an important regulator of the major recycling pathways of LNP-delivered siRNAs. NPC1-deficient cells show enhanced cellular retention of LNPs inside late endosomes/lysosomes and increased gene silencing of the target gene. Our data suggests that siRNA delivery efficiency might be improved by designing delivery vehicles that can escape the recycling pathways

    HTLV-1 and HIV-2 Infection Are Associated with Increased Mortality in a Rural West African Community

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    BACKGROUND: Survival of people with HIV-2 and HTLV-1 infection is better than that of HIV-1 infected people, but long-term follow-up data are rare. We compared mortality rates of HIV-1, HIV-2, and HTLV-1 infected subjects with those of retrovirus-uninfected people in a rural community in Guinea-Bissau. METHODS: In 1990, 1997 and 2007, adult residents (aged ≥15 years) were interviewed, a blood sample was drawn and retroviral status was determined. An annual census was used to ascertain the vital status of all subjects. Cox regression analysis was used to estimate mortality hazard ratios (HR), comparing retrovirus-infected versus uninfected people. RESULTS: A total of 5376 subjects were included; 197 with HIV-1, 424 with HIV-2 and 325 with HTLV-1 infection. The median follow-up time was 10.9 years (range 0.0-20.3). The crude mortality rates were 9.6 per 100 person-years of observation (95% confidence interval 7.1-12.9) for HIV-1, 4.1 (3.4-5.0) for HIV-2, 3.6 (2.9-4.6) for HTLV-1, and 1.6 (1.5-1.8) for retrovirus-negative subjects. The HR comparing the mortality rate of infected to that of uninfected subjects varied significantly with age. The adjusted HR for HIV-1 infection varied from 4.0 in the oldest age group (≥60 years) to 12.7 in the youngest (15-29 years). The HR for HIV-2 infection varied from 1.2 (oldest) to 9.1 (youngest), and for HTLV-1 infection from 1.2 (oldest) to 3.8 (youngest). CONCLUSIONS: HTLV-1 infection is associated with significantly increased mortality. The mortality rate of HIV-2 infection, although lower than that of HIV-1 infection, is also increased, especially among young people
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