629 research outputs found
RijeÄ akademika Josipa Torbarine, tajnika Razreda za filologiju JAZU
Physical ocean processes (ice-melt, island run-off and upwelling of nutrients) were hypothesised to affect the bacterioplankton composition in the surface mixed layer of the Scotia Sea during the austral summer of 2003, and this was investigated using flow cytometry and catalysed reporter deposition fluorescence in situ hybridisation (CARD-FISH) techniques. The bacterioplankton was composed predominantly of Alphaproteobacteria (PB), comprising SAR11, Roseobacterspp. and SAR116 groups, followed by Sphingobacteria/Flavobacteria and Gammaproteobacteria, including SAR86. Two distinct bacterioplankton communities were identified, largely based on bacterioplankton abundance, which varied from 0.3 ± 0.06 Ă 106 cells mlâ1 in the west to 0.8 ± 0.3 Ă 106 cells mlâ1 in the east, and a corresponding difference in SAR11 percentages of 30 ± 15% in the west compared to 5 ± 5% in the east. The western community was present in waters that were largely in an over-wintered, pre-bloom condition. The eastern bacterioplankton community was associated with phytoplankton blooms developed within the eastern Scotia Sea nutrient upwelling zone, where the Antarctic Circumpolar Current (ACC) encounters the shallow bathymetry associated with the Scotia Arc, in combination with seasonal ice-melt and island effects that enabled surface water stratification
Cannabis use and risk of schizophrenia: a Mendelian randomization study.
Cannabis use is observationally associated with an increased risk of schizophrenia, but whether the relationship is causal is not known. Using a genetic approach, we took 10 independent genetic variants previously identified to associate with cannabis use in 32 330 individuals to determine the nature of the association between cannabis use and risk of schizophrenia. Genetic variants were employed as instruments to recapitulate a randomized controlled trial involving two groups (cannabis users vs nonusers) to estimate the causal effect of cannabis use on risk of schizophrenia in 34 241 cases and 45 604 controls from predominantly European descent. Genetically-derived estimates were compared with a meta-analysis of observational studies reporting ever use of cannabis and risk of schizophrenia or related disorders. Based on the genetic approach, use of cannabis was associated with increased risk of schizophrenia (odds ratio (OR) of schizophrenia for users vs nonusers of cannabis: 1.37; 95% confidence interval (CI), 1.09-1.67; P-value=0.007). The corresponding estimate from observational analysis was 1.43 (95% CI, 1.19-1.67; P-value for heterogeneity =0.76). The genetic markers did not show evidence of pleiotropic effects and accounting for tobacco exposure did not alter the association (OR of schizophrenia for users vs nonusers of cannabis, adjusted for ever vs never smoker: 1.41; 95% CI, 1.09-1.83). This adds to the substantial evidence base that has previously identified cannabis use to associate with increased risk of schizophrenia, by suggesting that the relationship is causal. Such robust evidence may inform public health messages about cannabis use, especially regarding its potential mental health consequences
Two-year-olds at elevated risk for ASD can learn novel words from their parents
Education and Child Studie
Generation and phenotypic characterization of Pde1a mutant mice
Contains fulltext :
177029.pdf (publisher's version ) (Open Access)It has been proposed that a reduction in intracellular calcium causes an increase in intracellular cAMP and PKA activity through stimulation of calcium inhibitable adenylyl cyclase 6 and inhibition of phosphodiesterase 1 (PDE1), the main enzymes generating and degrading cAMP in the distal nephron and collecting duct, thus contributing to the development and progression of autosomal dominant polycystic kidney disease (ADPKD). In zebrafish pde1a depletion aggravates and overexpression ameliorates the cystic phenotype. To study the role of PDE1A in a mammalian system, we used a TALEN pair to Pde1a exon 7, targeting the histidine-aspartic acid dipeptide involved in ligating the active site Zn++ ion to generate two Pde1a null mouse lines. Pde1a mutants had a mild renal cystic disease and a urine concentrating defect (associated with upregulation of PDE4 activity and decreased protein kinase A dependent phosphorylation of aquaporin-2) on a wild-type genetic background and aggravated renal cystic disease on a Pkd2WS25/- background. Pde1a mutants additionally had lower aortic blood pressure and increased left ventricular (LV) ejection fraction, without a change in LV mass index, consistent with the high aortic and low cardiac expression of Pde1a in wild-type mice. These results support an important role of PDE1A in the renal pathogenesis of ADPKD and in the regulation of blood pressure
Is It Fear?: Similar brain responses to fearful and neutral faces in infants with a heightened likelihood for autism spectrum disorder
Education and Child Studie
The status of GEO 600
The GEO 600 laser interferometer with 600m armlength is part of a worldwide network of gravitational wave detectors. GEO 600 is unique in having advanced multiple pendulum suspensions with a monolithic last stage and in employing a signal recycled optical design. This paper describes the recent commissioning of the interferometer and its operation in signal recycled mode
Thermostatistics of deformed bosons and fermions
Based on the q-deformed oscillator algebra, we study the behavior of the mean
occupation number and its analogies with intermediate statistics and we obtain
an expression in terms of an infinite continued fraction, thus clarifying
successive approximations. In this framework, we study the thermostatistics of
q-deformed bosons and fermions and show that thermodynamics can be built on the
formalism of q-calculus. The entire structure of thermodynamics is preserved if
ordinary derivatives are replaced by the use of an appropriate Jackson
derivative and q-integral. Moreover, we derive the most important thermodynamic
functions and we study the q-boson and q-fermion ideal gas in the thermodynamic
limit.Comment: 14 pages, 2 figure
Track Finding Efficiency in BaBar
We describe several studies to measure the charged track reconstruction
efficiency and asymmetry of the BaBar detector. The first two studies measure
the tracking efficiency of a charged particle using and initial state
radiation decays. The third uses the decays to study the asymmetry in
tracking, the fourth measures the tracking efficiency for low momentum tracks,
and the last measures the reconstruction efficiency of particles. The
first section also examines the stability of the measurements vs BaBar running
periods.Comment: 20 pages, 30 figures, Submitted to Nuclear Instruments and Methods in
Physics Research
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in âs = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fbâ1 of protonâproton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
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