331 research outputs found
Search for supersymmetric particles in scenarios with a gravitino LSP and stau NLSP
Sleptons, neutralinos and charginos were searched for in the context of
scenarios where the lightest supersymmetric particle is the gravitino. It was
assumed that the stau is the next-to-lightest supersymmetric particle. Data
collected with the DELPHI detector at a centre-of-mass energy near 189 GeV were
analysed combining the methods developed in previous searches at lower
energies. No evidence for the production of these supersymmetric particles was
found. Hence, limits were derived at 95% confidence level.Comment: 31 pages, 14 figure
Seasonal pattern of peptic ulcer hospitalizations: analysis of the hospital discharge data of the Emilia-Romagna region of Italy
BACKGROUND:
Previous studies have reported seasonal variation in peptic ulcer disease (PUD), but few large-scale, population-based studies have been conducted.
METHODS:
To verify whether a seasonal variation in cases of PUD (either complicated or not complicated) requiring acute hospitalization exists, we assessed the database of hospital admissions of the region Emilia Romagna (RER), Italy, obtained from the Center for Health Statistics, between January 1998 and December 2005. Admissions were categorized by sex, age ( or = 75 yrs), site of PUD lesion (stomach or duodenum), main complication (hemorrhage or perforation), and final outcome (intended as fatal outcome: in-hospital death; nonfatal outcome: patient discharged alive). Temporal patterns in PUD admissions were assessed in two ways, considering a) total counts per single month and season, and b) prevalence proportion, such as the monthly prevalence of PUD admissions divided by the monthly prevalence of total hospital admissions, to assess if the temporal patterns in the raw data might be the consequence of seasonal and annual variations in hospital admissions per se in the region. For statistical analysis, the chi2 test for goodness of fit and inferential chronobiologic method (Cosinor and partial Fourier series) were used.
RESULTS:
Of the total sample of PUD patients (26,848 [16,795 males, age 65 +/- 16 yrs; 10,053 females, age 72 +/- 15 yrs, p or = 75 yrs of age. There were more cases of duodenal (DU). (89.8%) than gastric ulcer (GU) (3.6%), and there were 1,290 (4.8%) fatal events. Data by season showed a statistically difference with the lowest proportion of PUD hospital admissions in summer (23.3%) (p < 0.001), for total cases and rather all subgroups. Chronobiological analysis identified three major peaks of PUD hospitalizations (September-October, January-February, and April-May) for the whole sample (p = 0.035), and several subgroups, with nadir in July. Finally, analysis of the monthly prevalence proportions yielded a significant (p = 0.025) biphasic pattern with a main peak in August-September-October, and a secondary one in January-February.
CONCLUSIONS:
A seasonal variation in PUD hospitalization, characterized by three peaks of higher incidence (Autumn, Winter, and Spring) is observed. When data corrected by monthly admission proportions are analyzed, late summer-autumn and winter are confirmed as higher risk periods. The underlying pathophysiologic mechanisms are unknown, and need further studies. In subjects at higher risk, certain periods of the year could deserve an appropriate pharmacological protection to reduce the risk of PUD hospitalization
Measurement of Trilinear Gauge Couplings in Collisions at 161 GeV and 172 GeV
Trilinear gauge boson couplings are measured using data taken by DELPHI at 161~GeV and 172~GeV. Values for couplings () are determined from a study of the reactions \eeWW\ and \eeWev, using differential distributions from the final state in which one decays hadronically and the other leptonically, and total cross-section data from other channels. Limits are also derived on neutral couplings from an analysis of the reaction \eegi
Study of B0_s anti-B0_s oscillations and B0_s lifetimes using hadronic decays of B0_s mesons
Oscillations of B0s mesons have been studied in samples selected from about
3.5 million hadronic Z decays detected by DELPHI between 1992 and 1995. One
analysis uses events in the exclusive decay channels: B0s -> Ds- pi+ or Ds- a1+
and B0s -> anti-D0 K- pi+ or anti-D0 K- a1+, where the D decays are completely
reconstructed. In addition, B0s anti-B0s oscillations have been studied in
events with an exclusively reconstructed Ds accompanied in the same hemisphere
by a high momentum hadron of opposite charge. Combining the two analyses, a
limit on the mass difference between the physical B0s states has been obtained:
Delta(m_B0s) > 4.0 ps^{-1} at the 95% C.L. with a sensitivity of Delta(m_B0s)
= 3.2 ps^{-1}. Using the latter sample of events, the B0s lifetime has been
measured and an upper limit on the decay width difference between the two
physical B0s states has been obtained:
tau(B0s) = 1.53^{+0.16}_{-0.15}(stat.) +/- {0.07}(syst.) ps
\Delta\Gamma(B0s)/\Gamma(B0s) < 0.69 at the 95% C.L.
The combination of these results with those obtained using Ds+- lepton-+
sample gives:
Delta(m_B0s) > 4.9 ps^{-1} at the 95% C.L.
with a sensitivity of Delta(m_B0s) = 8.7 ps^{-1}.
tau(B0s) = 1.46 +/- 0.11 ps and \Delta\Gamma(B0s)/\Gamma(B0s) < 0.45 at the
95% C.L.Comment: 42 pages, 13 figure
Evacetrapib and Cardiovascular Outcomes in High-Risk Vascular Disease
BACKGROUND:
The cholesteryl ester transfer protein inhibitor evacetrapib substantially raises the high-density lipoprotein (HDL) cholesterol level, reduces the low-density lipoprotein (LDL) cholesterol level, and enhances cellular cholesterol efflux capacity. We sought to determine the effect of evacetrapib on major adverse cardiovascular outcomes in patients with high-risk vascular disease.
METHODS:
In a multicenter, randomized, double-blind, placebo-controlled phase 3 trial, we enrolled 12,092 patients who had at least one of the following conditions: an acute coronary syndrome within the previous 30 to 365 days, cerebrovascular atherosclerotic disease, peripheral vascular arterial disease, or diabetes mellitus with coronary artery disease. Patients were randomly assigned to receive either evacetrapib at a dose of 130 mg or matching placebo, administered daily, in addition to standard medical therapy. The primary efficacy end point was the first occurrence of any component of the composite of death from cardiovascular causes, myocardial infarction, stroke, coronary revascularization, or hospitalization for unstable angina.
RESULTS:
At 3 months, a 31.1% decrease in the mean LDL cholesterol level was observed with evacetrapib versus a 6.0% increase with placebo, and a 133.2% increase in the mean HDL cholesterol level was seen with evacetrapib versus a 1.6% increase with placebo. After 1363 of the planned 1670 primary end-point events had occurred, the data and safety monitoring board recommended that the trial be terminated early because of a lack of efficacy. After a median of 26 months of evacetrapib or placebo, a primary end-point event occurred in 12.9% of the patients in the evacetrapib group and in 12.8% of those in the placebo group (hazard ratio, 1.01; 95% confidence interval, 0.91 to 1.11; P=0.91).
CONCLUSIONS:
Although the cholesteryl ester transfer protein inhibitor evacetrapib had favorable effects on established lipid biomarkers, treatment with evacetrapib did not result in a lower rate of cardiovascular events than placebo among patients with high-risk vascular disease. (Funded by Eli Lilly; ACCELERATE ClinicalTrials.gov number, NCT01687998 .)
Crowd vocal learning induces vocal dialects in bats: Playback of conspecifics shapes fundamental frequency usage by pups
Vocal learning, the substrate of human language acquisition, has rarely been described in other mammals. Often, group-specific vocal dialects in wild populations provide the main evidence for vocal learning. While social learning is often the most plausible explanation for these intergroup differences, it is usually impossible to exclude other driving factors, such as genetic or ecological backgrounds. Here, we show the formation of dialects through social vocal learning in fruit bats under controlled conditions. We raised 3 groups of pups in conditions mimicking their natural roosts. Namely, pups could hear their mothers\u27 vocalizations but were also exposed to a manipulation playback. The vocalizations in the 3 playbacks mainly differed in their fundamental frequency. From the age of approximately 6 months and onwards, the pups demonstrated distinct dialects, where each group was biased towards its playback. We demonstrate the emergence of dialects through social learning in a mammalian model in a tightly controlled environment. Unlike in the extensively studied case of songbirds where specific tutors are imitated, we demonstrate that bats do not only learn their vocalizations directly from their mothers, but that they are actually influenced by the sounds of the entire crowd. This process, which we term “crowd vocal learning,” might be relevant to many other social animals such as cetaceans and pinnipeds
Evidence for Dialects in Three Captive Populations of Common Marmosets (Callithrix jacchus)
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