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Maximizing ENSO as a source of western US hydroclimate predictability
Until recently, the El NiĂąoâSouthern Oscillation (ENSO) was considered a reliable source of winter precipitation predictability in the western US, with a historically strong link between extreme El NiĂąo events and extremely wet seasons. However, the 2015â2016 El NiĂąo challenged our understanding of the ENSO-precipitation relationship. California precipitation was near-average during the 2015â2016 El NiĂąo, which was characterized by warm sea surface temperature (SST) anomalies of similar magnitude compared to the extreme 1997â1998 and 1982â1983 El NiĂąo events. We demonstrate that this precipitation response can be explained by El NiĂąoâs spatial pattern, rather than internal atmospheric variability. In addition, observations and large-ensembles of regional and global climate model simulations indicate that extremes in seasonal and daily precipitation during strong El NiĂąo events are better explained using the ENSO Longitude Index (ELI), which captures the diversity of ENSOâs spatial patterns in a single metric, compared to the traditional NiĂąo3.4 index, which measures SST anomalies in a fixed region and therefore fails to capture ENSO diversity. The physically-based ELI better explains western US precipitation variability because it tracks the zonal shifts in tropical Pacific deep convection that drive teleconnections through the response in the extratropical wave-train, integrated vapor transport, and atmospheric rivers. This research provides evidence that ELI improves the value of ENSO as a predictor of Californiaâs seasonal hydroclimate extremes compared to traditional ENSO indices, especially during strong El NiĂąo events
Foraging patterns of acorn woodpeckers (Melanerpes formicivorus) on valley oak (Quercus lobata NĂŠe) in two California oak savanna-woodlands
Landscape characteristics and social behavior can affect the foraging patterns of seed-dependent animals. We examine the movement of acorns from valley oak (Quercus lobata) trees to granaries maintained by acorn woodpeckers (Melanerpes formicivorus) in two California oak savanna-woodlands differing in the distribution of Q. lobata within each site. In 2004, we sampled Q. lobata acorns from 16 granaries at Sedgwick Reserve in Santa Barbara County and 18 granaries at Hastings Reserve in Monterey County. Sedgwick has lower site-wide density of Q. lobata than Hastings as well as different frequencies of other Quercus species common to both sites. We found acorn woodpeckers foraged from fewer Q. lobata seed source trees (Kg = 4.1 ¹ 0.5) at Sedgwick than at Hastings (Kg = 7.6 ¹ 0.6) and from fewer effective seed sources (Nem* = 2.00 and 5.78, respectively). The differences between sites are due to a greater number of incidental seed sources used per granary at Hastings than at Sedgwick. We also found very low levels of seed source sharing between adjacent granaries, indicating that territoriality is strong at both sites and that each social group forages on its own subset of trees. We discovered an interesting spatial pattern in the location of granaries. At Sedgwick, acorn woodpeckers situated their granaries within areas of higher-than-average tree density, while at Hastings, they placed them within areas of lower-than-average tree density, with the outcome that granaries at the two sites were located in areas of similar valley oak density. Our results illustrate that landscape characteristics might influence the number of trees visited by acorn woodpeckers and the locations of territories, while woodpecker social behavior, such as territoriality, shapes which trees are visited and whether they are shared with other social groups
Assessment of knowledge about childhood autism among paediatric and psychiatric nurses in Ebonyi state, Nigeria
<p>Abstract</p> <p>Background</p> <p>There is increasing public and professional awareness of autism spectrum disorders with early recognition, diagnosis and interventions that are known to improve prognosis. Poor knowledge about childhood autism among paediatric and psychiatric nurses who are members of multidisciplinary teams that care for such children may be a major barrier to early interventions that could improve quality of life and prognosis in childhood autism. Factors that influence knowledge about childhood autism among these nurses are not known. This study assessed knowledge about childhood autism among paediatric and psychiatric nurses in Ebonyi state, Nigeria and determined the factors that could be influencing such knowledge.</p> <p>Methods</p> <p>Forty specialist paediatric and forty psychiatric nurses, making a total sample of eighty, were randomly selected from all the health care facilities in Ebonyi state, Nigeria. A socio-demographic questionnaire and knowledge about childhood autism among health workers (KCAHW) questionnaire were administered to them and the study was a point survey.</p> <p>Results</p> <p>The total mean score on the KCAHW questionnaire among the nurses that participated in the study was 12.56 Âą 3.23 out of a total of 19 possible. The mean score for the paediatric nurses was 11.78 Âą 3.64 while psychiatric nurses had mean score of 13.35 Âą 2.58. The mean scores in Domain 1 were 6.17 Âą 1.75 for the paediatric nurses and 6.52 Âą 1.43 for the psychiatric nurses. The mean scores in Domain 2 were 0.65 Âą 0.48 for the paediatric nurses and 0.80 Âą 0.41 for the psychiatric nurses. Domain 3 showed mean scores of 1.97 Âą 1.25 for the paediatric nurses while psychiatric nurses scored 2.62 Âą 1.23. Domain 4 yielded the mean scores of 2.97 Âą 1.54 and 3.42 Âą 0.98 for the paediatric and psychiatric nurses respectively.</p> <p>There was significant relationship between the total mean score on the KCAHW questionnaire for the two groups and the area of specialisation of the nurses (t = -2.23, df = 78, p = 0.03) and there was also significant relationship between previous involvement in managing children with childhood autism as a specialist paediatric or psychiatric nurse and the total mean score on the KCAHW questionnaire (t = 6.90, df = 78, p = 0.00).</p> <p>Conclusion</p> <p>The scores reflect deficits in knowledge about childhood autism among the study cohorts. Paediatric and psychiatric nurses as members of multidisciplinary teams that care for children with childhood autism are expected to provide holistic care and adequate counselling to the families of these children. Unfortunately in this environment, they are not fully equipped with enough knowledge about childhood autism. Education on childhood autism is therefore needed and can be provided through continuing medical education and emphasizing childhood autism in their training curriculum. This will enhance early identification and diagnosis of childhood autism with early interventions that are known to improve prognosis.</p
The time-profile of cell growth in fission yeast: model selection criteria favoring bilinear models over exponential ones
BACKGROUND: There is considerable controversy concerning the exact growth profile of size parameters during the cell cycle. Linear, exponential and bilinear models are commonly considered, and the same model may not apply for all species. Selection of the most adequate model to describe a given data-set requires the use of quantitative model selection criteria, such as the partial (sequential) F-test, the Akaike information criterion and the Schwarz Bayesian information criterion, which are suitable for comparing differently parameterized models in terms of the quality and robustness of the fit but have not yet been used in cell growth-profile studies. RESULTS: Length increase data from representative individual fission yeast (Schizosaccharomyces pombe) cells measured on time-lapse films have been reanalyzed using these model selection criteria. To fit the data, an extended version of a recently introduced linearized biexponential (LinBiExp) model was developed, which makes possible a smooth, continuously differentiable transition between two linear segments and, hence, allows fully parametrized bilinear fittings. Despite relatively small differences, essentially all the quantitative selection criteria considered here indicated that the bilinear model was somewhat more adequate than the exponential model for fitting these fission yeast data. CONCLUSION: A general quantitative framework was introduced to judge the adequacy of bilinear versus exponential models in the description of growth time-profiles. For single cell growth, because of the relatively limited data-range, the statistical evidence is not strong enough to favor one model clearly over the other and to settle the bilinear versus exponential dispute. Nevertheless, for the present individual cell growth data for fission yeast, the bilinear model seems more adequate according to all metrics, especially in the case of wee1Î cells
FRAX (R): Prediction of Major Osteoporotic Fractures in Women from the General Population: The OPUS Study
Purposes: The aim of this study was to analyse how well FRAXH predicts the risk of major osteoporotic and vertebral
fractures over 6 years in postmenopausal women from general population.
Patients and methods: The OPUS study was conducted in European women aged above 55 years, recruited in 5 centers
from random population samples and followed over 6 years. The population for this study consisted of 1748 women (mean
age 74.2 years) with information on incident fractures. 742 (43.1%) had a prevalent fracture; 769 (44%) and 155 (8.9%) of
them received an antiosteoporotic treatment before and during the study respectively. We compared FRAXH performance
with and without bone mineral density (BMD) using receiver operator characteristic (ROC) c-statistical analysis with ORs and
areas under receiver operating characteristics curves (AUCs) and net reclassification improvement (NRI).
Results: 85 (4.9%) patients had incident major fractures over 6 years. FRAXH with and without BMD predicted these
fractures with an AUC of 0.66 and 0.62 respectively. The AUC were 0.60, 0.66, 0.69 for history of low trauma fracture alone,
age and femoral neck (FN) BMD and combination of the 3 clinical risk factors, respectively. FRAXH with and without BMD
predicted incident radiographic vertebral fracture (n = 65) with an AUC of 0.67 and 0.65 respectively. NRI analysis showed a
significant improvement in risk assignment when BMD is added to FRAXH.
Conclusions: This study shows that FRAXH with BMD and to a lesser extent also without FN BMD predict major osteoporotic
and vertebral fractures in the general population
The role of emergency neurology in Italy: outcome of a consensus meeting for a intersociety position
A possible definition of clinical, educational and organizing aspects of emergency neurology in Italy is reported in this position paper of Emergency Neurology Intersociety Group, created in 2008 among the two neurological Societies in Italy: SocietĂ Italiana di Neurologia and SocietĂ di Neuroscienze Ospedaliere. The aim of this Group has been the evaluation of the role of neurologist in the emergency setting of Italian hospitals, as well as of the description of different scenarios in which a ward dedicated to a semi-intensive care of neurological emergencies could have a role in the actual organization of academic or general hospitals in our Country. The actual great relevance of neurologist activity in the inpatients treatment, in fact, is actually misleaded as it is the considerable significance of neurological expertise, techniques and support in hospital care pathways also involving neurological manifestations throughout the course of other diseases. Finally, the possible contents of educational programs orienting neurological specialty towards a better comprehension and management of emergency neurological problems either in terms of specific formation or of techniques to be learned by emergency neurologist, are reported as a results of the Consensus Workshop hold in Castiglioncello (LI) in September 12th, 2009
Measurement of B meson production cross-sections in proton-proton collisions at âs= 7 TeV
The production cross-sections of B mesons are measured in pp collisions at a centre-of-mass energy of 7 TeV using data collected with the LHCb detector corresponding to a integrated luminosity of 0.36fbâ1. The B+, B0 and B0s mesons are reconstructed in the exclusive decays B+âJ/ĎK+, B0âJ/ĎKâ0 and B0sâJ/ĎĎ, with J/ĎâÎź+Îźâ, Kâ0âK+Ďâ and ĎâK+Kâ. The differential cross-sections are measured as functions of B meson transverse momentum pT and rapidity y, in the range 0 < pT<40GeV/c2 and 2.0<y<4.5. The integrated cross-sections in the same pT and y ranges, including charge-conjugate states, are measured to be
Ď(ppâB++X)=38.9Âą0.3(stat.)Âą2.5(syst.)Âą1.3(norm.)Îźb,
Ď(ppâB0+X)=38.1Âą0.6(stat.)Âą3.7(syst.)Âą4.7(norm.)Îźb,
Ď(ppâB0s+X)=10.5Âą0.2(stat.)Âą0.8(syst.)Âą1.0(norm.)Îźb,
where the third uncertainty arises from the pre-existing branching fraction measurements
Differential branching fraction and angular analysis of decays
The differential branching fraction of the rare decay is measured as a function of , the
square of the dimuon invariant mass. The analysis is performed using
proton-proton collision data, corresponding to an integrated luminosity of 3.0
\mbox{ fb}^{-1}, collected by the LHCb experiment. Evidence of signal is
observed in the region below the square of the mass. Integrating
over 15 < q^{2} < 20 \mbox{ GeV}^2/c^4 the branching fraction is measured as
d\mathcal{B}(\Lambda^{0}_{b} \rightarrow \Lambda \mu^+\mu^-)/dq^2 = (1.18 ^{+
0.09} _{-0.08} \pm 0.03 \pm 0.27) \times 10^{-7} ( \mbox{GeV}^{2}/c^{4})^{-1},
where the uncertainties are statistical, systematic and due to the
normalisation mode, , respectively.
In the intervals where the signal is observed, angular distributions are
studied and the forward-backward asymmetries in the dimuon ()
and hadron () systems are measured for the first time. In the
range 15 < q^2 < 20 \mbox{ GeV}^2/c^4 they are found to be A^{l}_{\rm FB} =
-0.05 \pm 0.09 \mbox{ (stat)} \pm 0.03 \mbox{ (syst)} and A^{h}_{\rm FB} =
-0.29 \pm 0.07 \mbox{ (stat)} \pm 0.03 \mbox{ (syst)}.Comment: 27 pages, 10 figures, Erratum adde
Secondary Prevention of Suicide
Leo Sher and colleagues discuss recent research on interventions to prevent secondary suicide and discuss the additional research that is needed
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
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