3,722 research outputs found
High-energy Atmospheric Muon Flux Expected at India-Based Neutrino Observatory
We calculate the zenith-angle dependence of conventional and prompt
high-energy muon fluxes at India-Based Neutrino Observatory (INO) depth. This
study demonstrates a possibility to discriminate models of the charm
hadroproduction including the low-x QCD behaviour of hadronic cross-sections
relevant at very high energies.Comment: 10 pages. 8 figures, 3 table
HIV-1 Directly Kills CD4+ T Cells by a Fas-independent Mechanism
The mechanism by which HIV-1 induces CD4+ T cell death is not known. A fundamental issue is whether HIV-1 primarily induces direct killing of infected cells or indirectly causes death of uninfected bystander cells. This question was studied using a reporter virus system in which infected cells are marked with the cell surface protein placental alkaline phosphatase (PLAP). Infection by HIV-PLAP of peripheral blood mononuclear cells (PBMCs) and T cell lines leads to rapid depletion of CD4+ T cells and induction of apoptosis. The great majority of HIV-induced T cell death in vitro involves direct loss of infected cells rather than indirect effects on uninfected bystander cells. Because of its proposed role in HIV-induced cell death, we also examined the Fas (CD95/Apo1) pathway in killing of T cells by HIV-1. Infected PBMCs or CEM cells display no increase in surface Fas relative to uninfected cells. In addition, HIV-1 kills CEM and Jurkat T cells in the presence of a caspase inhibitor that completely blocks Fas-mediated apoptosis. HIV-1 also depletes CD4+ T cells in PBMCs from patients who have a genetically defective Fas pathway. These results suggest that HIV-1 induces direct apoptosis of infected cells and kills T cells by a Fas-independent mechanism
Probing Pseudo-Dirac Neutrino through Detection of Neutrino Induced Muons from GRB Neutrinos
The possibility to verify the pseudo-Dirac nature of neutrinos is
investigated here via the detection of ultra high energy neutrinos from distant
cosmological objects like GRBs. The very long baseline and the energy range
from TeV to EeV for such neutrinos invokes the likelihood to
probe very small pseude-Dirac splittings. The expected secondary muons from
such neutrinos that can be detected by a kilometer scale detector such as
ICECUBE is calculated. The pseudo-Dirac nature, if exists, will show a
considerable departure from flavour oscillation scenario in the total yield of
the secondary muons induced by such neutrinos.Comment: 11 pages, 3figure
Depressive symptoms are common among rural Malawian adolescents
BackgroundDepressive conditions cause about 25 million disability adjusted life years in low-income countries annually. The incidence of depression rises after puberty, and the young age distribution in these countries may cause a high burden of adolescent depression. We aimed to assess the prevalence of reported depressive symptoms among rural adolescents in Malawi. Additionally, we assessed the association between birth weight, childhood growth, gender, and pubertal maturity and depressive symptoms. MethodsWe followed 767 children from the foetal period until 15-years-of-age. We used the Short Mood and Feelings Questionnaire (SMFQ) to examine reported depressive symptoms at 15years. The questionnaire was translated to local language and then back-translated until inaccuracies were not detected. Anthropometry was conducted at 1, 24, 120, and 180months of age. We performed regression models with imputed data to assess associations between the independent variables and depressive symptoms. As a sensitivity analysis, we ran the same regression models with participants with no missing data. ResultsA total of 523 participants were seen at 15years. The mean SMFQ score was 15 with 90% (95%CI 87-92%) of the participants scoring 11 points, the traditional cut-off for screening for depression. Birth weight, growth, gender, and pubertal maturity were not associated with the SMFQ score in the primary imputed analyses. In the sensitivity analysis, birth weight was associated with the SMFQ score in all models. ConclusionsThe prevalence of reported depressive symptoms was high among the studied population. It is uncertain how well the traditional cut-off of 11 points identifies children with clinically significant depressive symptoms in our sample. Our data do not support a hypothesis of an association between growth, gender, or pubertal maturity and depressive symptoms. Nevertheless, our results highlight the importance of the awareness of mental health problems in low-income countries.Peer reviewe
Neutrino Induced Upward Going Muons from a Gamma Ray Burst in a Neutrino Telescope of Km^2 Area
The number of neutrino induced upward going muons from a single Gamma Ray
Burst (GRB) expected to be detected by the proposed kilometer scale IceCube
detector at the South Pole location has been calculated. The effects of the
Lorentz factor, total energy of the GRB emitted in neutrinos and its distance
from the observer (red shift) on the number of neutrino events from the GRB
have been examined. The present investigation reveals that there is possibility
of exploring the early Universe with the proposed kilometer scale IceCube
neutrino telescope.Comment: 18pages, 5 figures. Physical Review D in pres
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The ConStratO model of handover: a tool to support technology design and evaluation
Handovers are a specific kind of multidisciplinary team meeting. Shift handovers and transfers are both regular features of hospital work but there is currently great variation in how such handovers are conducted, presenting a challenging for those seeking to develop technology to support handover. This paper presents the ConStratO model of handover, which captures aspects of the context that influence how the handover is conducted, a range of different handover strategies relating to different aspects of the handover, and possible outcomes of handover. The model is based on detailed data collection in a range of clinical settings. We present the model as a tool for developing and evaluating technology support for handover
Observability of Earth-skimming Ultra-high Energy Neutrinos
Neutrinos with energies above 10^8 GeV are expected from cosmic ray
interactions with the microwave background and are predicted in many
speculative models. Such energetic neutrinos are difficult to detect, as they
are shadowed by the Earth, but rarely interact in the atmosphere. Here we
propose a novel detection strategy: Earth-skimming neutrinos convert to charged
leptons that escape the Earth, and these leptons are detected in ground level
fluorescence detectors. With the existing HiRes detector, neutrinos from some
proposed sources are marginally detectable, and improvements of two orders of
magnitude are possible at the proposed Telescope Array.Comment: 4 pages, 3 figure
PHARMACOGNOSTIC STUDIES AND HPTLC FINGERPRINTING OF BLUMEA ERIANTHA DC (ASTERACEAE) LEAVES
Objective: To study the pharamacognostic, morphological, microscopical characters of leaves of Blumea eriantha DC also to carry out the chemical analysis of its leaf powder and establish the chromatographic fingerprint.Methods: Anatomical investigations and fluorescence analysis were carried out as per the standard techniques. Various quantitative parameters like ash values, extractive values and moisture content can be used as quality control parameters for B. eriantha were determined. The air dried leaf powder was extracted with methanol and fingerprinting pattern was developed by using High Performance Thin Layer Chromatography (HPTLC) technique. Results: The epidermal study of leaves revealed several stalked glandular trichomes and multicellular uniseriate trichomes on both the epidermis of the leaves. Fluorescence analysis of leaves powder of B. eriantha revealed a range of colours from dark green to brownish black under short Ultra Violet (UV) light. The HPTLC fingerprint of methanolic extract of B. eriantha leaves showed six well resolved components.Conclusion: The pharamacognostic studies carried out for Blumea eriantha DC and presented here provide referential information for the identification of this crude drug and will also help in distinguishing it from its adulterants
Role of Hippo Pathway-YAP/TAZ Signaling in Angiogenesis
Angiogenesis is a highly coordinated process of formation of new blood vessels from pre-existing blood vessels. The process of development of the proper vascular network is a complex process that is crucial for the vertebrate development. Several studies have defined essential roles of Hippo pathway-YAP/TAZ in organ size control, tissue regeneration, and self-renewal. Thus Hippo pathway is one of the central components in tissue homeostasis. There are mounting evidences on the eminence of Hippo pathway-YAP/TAZ in angiogenesis in multiple model organisms. Hippo pathway-YAP/TAZ is now demonstrated to regulate endothelial cell proliferation, migration and survival; subsequently regulating vascular sprouting, vascular barrier formation, and vascular remodeling. Major intracellular signaling programs that regulate angiogenesis concomitantly activate YAP/TAZ to regulate key events in angiogenesis. In this review, we provide a brief overview of the recent findings in the Hippo pathway and YAP/TAZ signaling in angiogenesis
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