Diabetes is a global health problem caused primarily by the inability of pancreatic β-cells to secrete adequate levels of insulin. The molecular mechanisms underlying the progressive failure of ...β-cells to respond to glucose in type-2 diabetes remain unresolved. Using a combination of transcriptomics and proteomics, we find significant dysregulation of major metabolic pathways in islets of diabetic βV59M mice, a non-obese, eulipidaemic diabetes model. Multiple genes/proteins involved in glycolysis/gluconeogenesis are upregulated, whereas those involved in oxidative phosphorylation are downregulated. In isolated islets, glucose-induced increases in NADH and ATP are impaired and both oxidative and glycolytic glucose metabolism are reduced. INS-1 β-cells cultured chronically at high glucose show similar changes in protein expression and reduced glucose-stimulated oxygen consumption: targeted metabolomics reveals impaired metabolism. These data indicate hyperglycaemia induces metabolic changes in β-cells that markedly reduce mitochondrial metabolism and ATP synthesis. We propose this underlies the progressive failure of β-cells in diabetes.
The signal of the GNSS satellites can be used to estimate the amount of water vapor in the atmosphere. For this reason, GNSS observations are nowadays routinely used by several meteorological ...institutes (e.g., MetOffice, Meteo France) to monitor weather events and to improve their weather forecasts quality. The analysis of a whole network of GNSS stations to estimate a full three-dimensional model of the water vapor content is a challenging and computationally demanding task. For this purpose, a tomographic system SEGAL GNSS Water Vapour Reconstruction Image Software (SWART) was developed and tested. The new method makes use of parallelized algebraic reconstruction techniques (ARTs) and supersedes other implementations in terms of speed by at least 50% for small networks. For SWART, the computation time grows linearly with the number of observations. As a result, the new method makes possible to estimate the water vapor for larger GNSS networks and can be used for near-real-time weather predictions. To show its potential, data from 26 stations in Poland were analyzed using data from a period of 56 days. Good agreement in the estimated water vapor between SWART and radiosondes solutions was obtained, with a mean RMS of 1.5 g/m
3
for the lower layers and an overall improvement of 5% until the layer 6750 m when compared with the atmospheric model (WRF). Furthermore, rapid and strong variations observed by radiosondes were not modeled by the WRF but were detected by GPS tomography.
We present results of a study of neutrino oscillation based on a 766 ton/year exposure of KamLAND to reactor antineutrinos. We observe 258 nu (e) candidate events with energies above 3.4 MeV compared ...to 365.2+/-23.7 events expected in the absence of neutrino oscillation. Accounting for 17.8+/-7.3 expected background events, the statistical significance for reactor nu (e) disappearance is 99.998%. The observed energy spectrum disagrees with the expected spectral shape in the absence of neutrino oscillation at 99.6% significance and prefers the distortion expected from nu (e) oscillation effects. A two-neutrino oscillation analysis of the KamLAND data gives Deltam(2)=7.9(+0.6)(-0.5)x10(-5) eV(2). A global analysis of data from KamLAND and solar-neutrino experiments yields Deltam(2)=7.9(+0.6)(-0.5)x10(-5) eV(2) and tan((2)theta=0.40(+0.10)(-0.07), the most precise determination to date.
KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ...ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded.
The detection of electron antineutrinos produced by natural radioactivity in the Earth could yield important geophysical information. The Kamioka liquid scintillator antineutrino detector (KamLAND) ...has the sensitivity to detect electron antineutrinos produced by the decay of 238U and 232Th within the Earth. Earth composition models suggest that the radiogenic power from these isotope decays is 16 TW, approximately half of the total measured heat dissipation rate from the Earth. Here we present results from a search for geoneutrinos with KamLAND. Assuming a Th/U mass concentration ratio of 3.9, the 90 per cent confidence interval for the total number of geoneutrinos detected is 4.5 to 54.2. This result is consistent with the central value of 19 predicted by geophysical models. Although our present data have limited statistical power, they nevertheless provide by direct means an upper limit (60 TW) for the radiogenic power of U and Th in the Earth, a quantity that is currently poorly constrained.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Kamioka Liquid scintillator Anti-Neutrino Detector is used in a search for single neutron or two-neutron intranuclear disappearance that would produce holes in the -shell energy level of (12)C ...nuclei. Such holes could be created as a result of nucleon decay into invisible modes (inv), e.g., n--> 3v or nn--> 2v. The deexcitation of the corresponding daughter nucleus results in a sequence of space and time-correlated events observable in the liquid scintillator detector. We report on new limits for one- and two-neutron disappearance: tau(n--> inv) > 5.8 x 10(29) years and tau (nn--> inv) > 1.4 x 10(30) years at 90% C.L. These results represent an improvement of factors of approximately 3 and >10(4) and over previous experiments.
Several clinical predictors of outcome in schizophrenia have been described; however, very few studies have examined neurobiological factors that predict outcome. The objective of this study was to ...examine the value of the morphology of the dorsolateral prefrontal cortex (DLPFC) determined by magnetic resonance imaging (MRI) as a predictor of short-term functional outcome in antipsychotic-naive patients with first-episode schizophrenia or schizoaffective disorder. Twenty-seven consecutive patients with first-episode schizophrenia or schizoaffective disorder underwent structural MRI at baseline. Functional outcome – a composite measure of social and employment subscales of the Strauss–Carpenter Scale – was assessed at 1 and 2 years. Volume of the left DLPFC at baseline predicted functional outcome in schizophrenia at 1 but not at 2 years. Specific cognitive functions regulated by the left DLPFC may be critical for functional outcome.
Summary
This paper examined the psychosocial predictors of weight loss among race and sex subgroups. Analyses included overweight and obese participants from the PREMIER study, a previously published ...randomized trial that examined the effects of two multi‐component lifestyle interventions on blood pressure among pre‐hypertensive and stage 1 hypertensive adults. Both intervention conditions received behavioural recommendations for weight loss and group sessions. Weight and psychosocial measures of self‐efficacy and social support for diet and exercise were assessed at baseline and at 6 months. There were 157 African–American (AA) women, 46 AA men, 203 non‐AA women and 182 non‐AA men with an average age of 50 years and average body mass index of 34 at baseline. Multiple predictor regression models were performed individually by race and sex subgroup. Among AA women, increases in diet self‐efficacy were associated with weight loss. Among AA men, increases in diet‐related social support and self‐efficacy, along with increases in family support to exercise, were associated with weight loss (all Ps <0.05). Among non‐AA women, increases in friends' support to exercise and exercise‐related self‐efficacy were associated with weight loss, and among non‐AA men only increases in diet self‐efficacy were associated with weight loss (all Ps <0.05). These results emphasize the need for targeted interventions based on race and sex to optimize the impact of lifestyle‐based weight loss programmes.
Neuropathological abnormalities in schizophrenia have been demonstrated in the parahippocampal gyrus (PHG). Only a few studies on first-episode neuroleptic-naive schizophrenia patients have been done ...using in vivo neuroimaging techniques. The authors examined the PHG morphology using structural MRI in neuroleptic-naive subjects with first episode psychoses. Volumetric measurements of PHG and intracranial volume (ICV) were obtained on subjects with schizophrenia and schizoaffective disorders (SCZ;
n=33), nonschizophrenia psychotic disorders (NSCZ;
n=11) and matched healthy subjects (HS;
n=43). The subjects were rated on the Brief Psychiatric Rating Scale (BPRS). Group differences and clinical correlations of ICV-adjusted PHG volumes were examined. Left PHG was significantly different across the groups consisting of SCZ, NSCZ and HS. PHG was larger in NSCZ compared to SCZ but not relative to HS. Bilaterally, PHG was no different between SCZ and HS. In pooled psychotic patients, the PHG volume negatively correlated with total positive symptom, delusion and conceptual disorganization scores on BPRS. Patients with delusions had relatively smaller PHG compared to nondelusional subjects. Observed differences in PHG volume in first-episode neuroleptic-naive patients suggest that these observations are not confounded by illness chronicity or medication effects. Significant association of PHG volume with psychotic symptoms suggests that PHG pathology plays an important role in the etiopathology of psychosis and its symptoms.
The proposed Majorana double-beta decay experiment is based on an array of segmented intrinsic Ge detectors with a total mass of 500 kg of Ge isotopically enriched to 86% in {sup 76}Ge. A discussion ...is given of background reduction by material selection, detector segmentation, pulse shape analysis, and electroformation of copper parts and granularity. Predictions of the experimental sensitivity are given. For an experimental running time of 10 years over the construction and operation of the Majorana setup, a sensitivity of T{sub 1/2}{sup 0{nu}} {approx} 4 x 10{sup 27} yr is predicted. This corresponds to <m{sub {nu}}> {approx} 0.003-0.004 eV according to recent QRPA and RQRPA matrix element calculations.
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