255 research outputs found
Study of the effect of neutrino oscillation on the supernova neutrino signal with the LVD detector
We present an update of our previous study (astro-ph/0112312) on how
oscillations affect the signal from a supernova core collapse observed in the
LVD detector at LNGS. In this paper we use a recent, more precise determination
of the cross section (astro-ph/0302055) to calculate the expected number of
inverse beta decay events, we introduce in the simulation also the -{\rm
Fe} interactions, we include the Earth matter effects and, finally, we study
also the inverted mass hierarchy case.Comment: 4 pages, 4 figures, to appear in the Proceedings of ICRC 200
Numbat nirvana: the conservation ecology of the endangered numbat Myrmecobius fasciatus (Marsupialia: Myrmecobiidae) reintroduced to Scotia and Yookamurra Sanctuaries, Australia
Despite a vigorous reintroduction program between 1985 and 2010, numbat populations in Western Australia are either static or declining. This study aimed to document the population ecology of numbats at two sites that are going against this trend: Scotia Sanctuary in far western New South Wales and Yookamurra Sanctuary in the riverland of South Australia. Scotia (64 659 ha) and Yookamurra (5026 ha) are conservation reserves owned and managed by the Australian Wildlife Conservancy and where numbats were reintroduced in 1999 and 1993 respectively. Both sites have large conservation-fence-protected introduced-species-free areas where there are no cats (Felis catus) or red foxes (Vulpes vulpes). Numbats were sourced from both wild and captive populations. From small founder populations, the Scotia numbats are now estimated to number 169 (113–225) with 44 at Yookamurra. Radio-collared individuals at Scotia were active between 13 and 31°C. Females had home ranges of 28.3 ± 6.8 ha and males 96.6 ± 18.2 ha, which leads to an estimated sustainable population or carrying capacity of 413–502 at Scotia. Captive-bred animals from Perth Zoo had a high mortality rate upon reintroduction at Scotia due to predation by raptors and starvation. The habitat preferences for mallee with a shrub understorey appear to be driven by availability of termites, and other reintroduced ecosystem engineers appear to have been facilitators by creating new refuge burrows for numbats. This study shows that numbats can be successfully reintroduced into areas of their former range if protected from introduced predators, and illustrates the difficulties in monitoring such cryptic species.</jats:p
Study of the effect of neutrino oscillations on the supernova neutrino signal in the LVD detector
The LVD detector, located in the INFN Gran Sasso National Laboratory (Italy),
studies supernova neutrinos through the interactions with protons and carbon
nuclei in the liquid scintillator and interactions with the iron nuclei of the
support structure. We investigate the effect of neutrino oscillations in the
signal expected in the LVD detector. The MSW effect has been studied in detail
for neutrinos travelling through the collapsing star and the Earth. We show
that the expected number of events and their energy spectrum are sensitive to
the oscillation parameters, in particular to the mass hierarchy and the value
of , presently unknown. Finally we discuss the astrophysical
uncertainties, showing their importance and comparing it with the effect of
neutrino oscillations on the expected signal.Comment: Accepted for pubblication on Astroparticle Physics. 36 pages, 18
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International survey on high- and low-dose synacthen test and assessment of accuracy in preparing low-dose synacthen
OBJECTIVE: The short synacthen test (SST) is widely used to assess patients for adrenal insufficiency but the frequency and protocols used across different centres for the low-dose test (LDT) are unknown. This study aimed to survey centres and test the accuracy of ten different synacthen preparation strategies used for the LDT. METHODS: Members of six international endocrine societies were surveyed regarding diagnostic tests used for adrenal insufficiency, and in particular the SST. Synacthen was diluted for the LDT and concentrations measured using a synacthen ELISA. RESULTS: Survey responses were received from 766 individuals across 60 countries (52% adult, 45% paediatric endocrinologists). The SST is used by 98% of centres: 92% using high-dose (250 μg), 43% low-dose, and 37% both. Ten low-dose dilution methods were assessed and variation in synacthen concentration was demonstrated with intra-method coefficients of variation (CV) ranging from 2.1% to 109%. The method using 5% dextrose as a diluent was the least variable (CV of 2.1%). The variation in dilution methods means that the dose of synacthen administered in a LDT may vary between 0.16 μg and 0.81 μg. CONCLUSIONS: The high-dose SST is the most popular diagnostic test of adrenal insufficiency but up to 72% of paediatric endocrinologists use a LDT. There is considerable variation observed both within and between low-dose synacthen dilution methods creating considerable risk of inaccurate dosing and thereby invalid results
Overexpression of the miR-17-92 cluster in colorectal adenoma organoids causes a carcinoma-like gene expression signature
Gain of chromosome arm 13q is one of the most prevalent DNA copy number alterations associated with colorectal adenoma-tocarcinoma progression. The oncogenic miR-17-92 cluster, located at 13q, was found to be overexpressed in colorectal cancer and in adenomas harboring 13q gain. However, to what extent overexpression of this group of microRNAs actually drives progression to cancer remains to be resolved. Therefore, we aimed to clarify the role of miR-17-92 cluster in the progression from colorectal adenoma to carcinoma.The miR-17-92 cluster was overexpressed in human colorectal adenoma organoids without 13q gain and downstream effects on mRNA expression were investigated, along with functional consequences in vitro and in vivo.Comparison of mRNA sequencing results of organoids overexpressing miR-17-92 and cultures transduced with control vector revealed a miR-17-92 expression signature. This signature appeared to be enriched in an independent series of colorectal cancers and adenomas with 13q gain, confirming that miR-17-92 expression is associated with malignant progression. However, tumor-associated characteristics, such as increased proliferation rate, were not observed in miR-17-92 overexpressing adenoma organoids in vitro. In addition, subcutaneous injection of these organoids in immunodeficient mice was insufficient to cause tumor outgrowth.In conclusion, this study showed that miR-17-92 expression contributes to 13q gain-associated adenoma-to-carcinoma progression, however, this is insufficient to cause malignancy.Cellular mechanisms in basic and clinical gastroenterology and hepatolog
Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: A systematic analysis for the Global Burden of Disease Study 2015
Background: The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context.
Methods: We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors—the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI).
Findings: Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6–58·8) of global deaths and 41·2% (39·8–42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa.
Interpretation: Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden.
Funding: Bill & Melinda Gates Foundation
Efeitos de ambiente e estimativas de parâmetros genéticos para características de carcaça em bovinos da raça Canchim criados em pastagem
Measurement of the ttbar Production Cross Section in ppbar collisions at sqrt s = 1.96 TeV in the All Hadronic Decay Mode
We report a measurement of the ttbar production cross section using the
CDF-II detector at the Fermilab Tevatron. The analysis is performed using 311
pb-1 of ppbar collisions at sqrt(s)=1.96 TeV. The data consist of events
selected with six or more hadronic jets with additional kinematic requirements.
At least one of these jets must be identified as a b-quark jet by the
reconstruction of a secondary vertex. The cross section is measured to be
sigma(tbart)=7.5+-2.1(stat.)+3.3-2.2(syst.)+0.5-0.4(lumi.) pb, which is
consistent with the standard model prediction.Comment: By CDF collaboratio
Search for long-lived doubly charged Higgs bosons in p(p)over-bar collisions at root s=1.96 TeV
We present a search for long-lived doubly charged Higgs bosons (H+/-+/-), with signatures of high ionization energy loss and muonlike penetration. We use 292 pb(-1) of data collected in p (p) over bar collisions at root s=1.96 TeV by the CDF II detector at the Fermilab Tevatron. Observing no evidence of long-lived doubly charged particle production, we exclude H-L(+/-+/-) and H-R(+/-+/-) bosons with masses below 133 GeV/c(2) and 109 GeV/c(2), respectively. In the degenerate case we exclude H+/-+/- mass below 146 GeV/c(2). All limits are quoted at the 95% confidence level
Search for chargino-neutralino production in ppbar collisions at sqrt(s) = 1.96 TeV
We present the results of a search for associated production of the chargino
and neutralino supersymmetric particles using up to 1.1 fb-1 of integrated
luminosity collected by the CDF II experiment at the Tevatron ppbar collider at
a center-of-mass energy of 1.96 TeV. The search is conducted by analyzing
events with a large transverse momentum imbalance and either three charged
leptons or two charged leptons of the same electric charge. The numbers of
observed events are found to be consistent with standard model expectations.
Upper limits on the production cross section are derived in different
theoretical models. In one of these models a lower limit on the mass of the
chargino is set at 129 GeV/c^2 at the 95% confidence level.Comment: To be submitted to Phys.Rev.Let
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