441 research outputs found

    Parallax of Galactic Cepheids from Spatially Scanning the Wide Field Camera 3 on the Hubble Space Telescope: The Case of SS Canis Majoris

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    We present a high-precision measurement of the parallax for the 12-day Cepheid SS Canis Majoris, obtained via spatial scanning with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). Spatial scanning enables astrometric measurements with a precision of 20-40 muas, an order of magnitude better than pointed observations. SS CMa is the second Cepheid targeted for parallax measurement with HST, and is the first of a sample of eighteen long-period >~ 10 days) Cepheids selected in order to improve the calibration of their period-luminosity relation and eventually permit a determination of the Hubble constant H_0 to better than 2%. The parallax of SS CMa is found to be 348 +/- 38 muas, corresponding to a distance of 2.9 +/- 0.3 kpc. We also present a refinement of the static geometric distortion of WFC3 obtained using spatial scanning observations of calibration fields, with a typical magnitude <~0.01 pixels on scales of 100 pixels.Comment: Submitted to ApJ on December 30, 2015. Comments welcome. Replaced original version to fix latex errors that prevented tables to sho

    Perturbative calculation of quasi-normal modes of Schwarzschild black holes

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    We discuss a systematic method of analytically calculating the asymptotic form of quasi-normal frequencies of a four-dimensional Schwarzschild black hole by expanding around the zeroth-order approximation to the wave equation proposed by Motl and Neitzke. We obtain an explicit expression for the first-order correction and arbitrary spin. Our results are in agreement with the results from WKB and numerical analyses in the case of gravitational waves.Comment: 11 pages; references added and a sign error corrected; to appear in CQ

    Cross talk between the Cell Wall Integrity and Cyclic AMP/Protein Kinase A pathways in Cryptococcus neoformans

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    Cryptococcus neoformans is a fungal pathogen of immunocompromised people that causes fatal meningitis. The fungal cell wall is essential to viability and pathogenesis of C. neoformans, and biosynthesis and repair of the wall is primarily controlled by the cell wall integrity (CWI) signaling pathway. Previous work has shown that deletion of genes encoding the four major kinases in the CWI signaling pathway, namely, PKC1, BCK1, MKK2, and MPK1 results in severe cell wall phenotypes, sensitivity to a variety of cell wall stressors, and for Mpk1, reduced virulence in a mouse model. Here, we examined the global transcriptional responses to gene deletions of BCK1, MKK2, and MPK1 compared to wild-type cells. We found that over 1,000 genes were differentially expressed in one or more of the deletion strains, with 115 genes differentially expressed in all three strains, many of which have been identified as genes regulated by the cyclic AMP (cAMP)/protein kinase A (PKA) pathway. Biochemical measurements of cAMP levels in the kinase deletion strains revealed significantly less cAMP in all of the deletion strains compared to the wild-type strain. The deletion strains also produced significantly smaller capsules than the wild-type KN99 strain did under capsule-inducing conditions, although the levels of capsule they shed were similar to those shed by the wild type. Finally, addition of exogenous cAMP led to reduced sensitivity to cell wall stress and restored surface capsule to levels near those of wild type. Thus, we have direct evidence of cross talk between the CWI and cAMP/PKA pathways that may have important implications for regulation of cell wall and capsule homeostasis

    Awareness of the Role of Nutrition in Cancer Causation and Prevention among Rural Adult Population: A Cross-sectional Study

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    Background In recent years, nutrition has received an increasingly important role in the aetiology of cancer. Thus, public education about dietary factors associated with cancer risk or prevention could be an important intervention for cancer prevention, particularly in low- and middle-income countries where the burden of cancer is increasing rapidly and access to care is limited. This study aimed to assess the awareness among rural adults about the role of nutrition in cancer development and its prevention. Methods A cross-sectional study was conducted among 300 individuals in the adult population (\u3e 18 years) in rural field practice area of a Medical College in South Karnataka for 3 months (June-August 2023) using a convenient sampling technique. Nutritional knowledge on cancer prevention was assessed using a semi-structured questionnaire which included sociodemographic details and multiple-choice questions. Data was entered in Microsoft Excel and analysed using descriptive and inferential statistics using SPSS V.26. Those who scored \u3e mean correct answer were considered as having good knowledge. Results Out of 300 study participants, 98% were aware of the disease of cancer, and 93% believed that nutrition played a role in cancer causation. 216 (72%) participants had good knowledge about role of nutrition in cancer causation and prevention whereas 84 (28%) had poor knowledge. A statistically significant association was observed between the participant’s age, religion and occupation with the knowledge level. Conclusion Majority of the participants had good knowledge about nutrition’s role in cancer causation and prevention

    Editorial: Endocrine modulators of neurological processes: potential treatment targets of pediatric neurological diseases.

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    Editorial on the Research Topic Endocrine Modulators of Neurological Processes: Potential Treatment Targets of Pediatric Neurological Diseases

    Successful maternal and fetal outcome in patients with Takayasu arteritis: two case reports of Type I and Type IV in stage 2

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    Takayasu's arteritis, is a rare, chronic, idiopathic, inflammatory disease of the large arteries, primarily involves the aorta, its main branches as well as the coronary and pulmonary arteries. It is mostly seen among women with child bearing age group (80%). During pregnancy, the increased intravascular volume impair circulation and exacerbate aortic regurgitation, hypertension, and congestive heart failure. Hypertension is one of the serious complication that can develop, leading to intrauterine growth restriction, maternal heart failure, and fetal haemorrhage and during postpartum period

    Epithelioid leiomyosarcoma: a rare uterine cancer

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    A uterine epithelioid leiomyosarcoma is a rare malignant tumour that arises from the smooth muscle lining the walls of the uterus. The exact cause of leiomyosarcoma, including uterine leiomyosarcoma accounting for 5 to 10% is unknown. Leiomyosarcoma is the most common subtype of uterine sarcoma, accounts for 1-2% of uterine malignancies. Malignancy should be suspected in menopausal women with tumour growth who are not on hormonal replacement therapy. A 64-year-old female had attained menopause 16 year back and developed postmenopausal bleeding since 2 months, with palpable mass, of 16 weeks size. Ultrasonography showed whorled mass lesions, endometrium and myometrium could not be seen separately. Uterus with both ovaries removed. Intra-operative findings showed 16 weeks uterine mass with size 15×10.5×10cm and weight 1kg with intramural fibroid. Necrotic and haemorrhagic areas with degenerative changes seen on cut section suggestive of malignancy. Histopathology and immunohistochemistry reported epithelioid leiomyosarcoma

    Introduction: reconsidering the region in India: mobilities, actors and development politics

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    In this introduction to a special issue on ‘Reconsidering the Region in India’, we aim to develop a synthetic and theoretically nuanced account of the multifarious ways in which the idea of region has been imbricated in diverse spatial, political, cultural and socio-economic configurations. We draw from various bodies of anthropological, geographic and historical literature to elaborate on three themes that we believe are central to understanding contemporary processes of region-making in India: trans-regional mobilities and connections; the actors who produce and perform regional imaginaries; and changing regional politics of development.IS

    Alcohol-related brain damage in humans

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    Chronic excessive alcohol intoxications evoke cumulative damage to tissues and organs. We examined prefrontal cortex (Brodmann’s area (BA) 9) from 20 human alcoholics and 20 age, gender, and postmortem delay matched control subjects. H & E staining and light microscopy of prefrontal cortex tissue revealed a reduction in the levels of cytoskeleton surrounding the nuclei of cortical and subcortical neurons, and a disruption of subcortical neuron patterning in alcoholic subjects. BA 9 tissue homogenisation and one dimensional polyacrylamide gel electrophoresis (PAGE) proteomics of cytosolic proteins identified dramatic reductions in the protein levels of spectrin β II, and α- and β-tubulins in alcoholics, and these were validated and quantitated by Western blotting. We detected a significant increase in α-tubulin acetylation in alcoholics, a non-significant increase in isoaspartate protein damage, but a significant increase in protein isoaspartyl methyltransferase protein levels, the enzyme that triggers isoaspartate damage repair in vivo. There was also a significant reduction in proteasome activity in alcoholics. One dimensional PAGE of membrane-enriched fractions detected a reduction in β-spectrin protein levels, and a significant increase in transmembranous α3 (catalytic) subunit of the Na+,K+-ATPase in alcoholic subjects. However, control subjects retained stable oligomeric forms of α-subunit that were diminished in alcoholics. In alcoholics, significant loss of cytosolic α- and β-tubulins were also seen in caudate nucleus, hippocampus and cerebellum, but to different levels, indicative of brain regional susceptibility to alcohol-related damage. Collectively, these protein changes provide a molecular basis for some of the neuronal and behavioural abnormalities attributed to alcoholics

    Cell wall composition in Cryptococcus neoformans is media dependent and alters host response, inducing protective immunity

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    INTRODUCTION: OBJECTIVE: The purpose of this study was to determine how different media influenced the amount of chitin and chitosan in the cell wall, which in turn impacted the cell wall architecture and host response. METHODS: Yeast extract, peptone, and dextrose (YPD) and yeast nitrogen base (YNB) are two commonly used media for growing Cryptococcus before use in in vitro or in vivo experiments. As a result, RESULTS: We observed that the growth of wild-type CONCLUSION: These findings emphasize the importance of culture media and pH during growth in shaping the content and organization of th
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