592 research outputs found
Observation of the Baryonic Flavor-Changing Neutral Current Decay Lambda_b -> Lambda mu+ mu-
We report the first observation of the baryonic flavor-changing neutral
current decay Lambda_b -> Lambda mu+ mu- with 24 signal events and a
statistical significance of 5.8 Gaussian standard deviations. This measurement
uses ppbar collisions data sample corresponding to 6.8fb-1 at sqrt{s}=1.96TeV
collected by the CDF II detector at the Tevatron collider. The total and
differential branching ratios for Lambda_b -> Lambda mu+ mu- are measured. We
find B(Lambda_b -> Lambda mu+ mu-) = [1.73+-0.42(stat)+-0.55(syst)] x 10^{-6}.
We also report the first measurement of the differential branching ratio of B_s
-> phi mu+ mu- using 49 signal events. In addition, we report branching ratios
for B+ -> K+ mu+ mu-, B0 -> K0 mu+ mu-, and B -> K*(892) mu+ mu- decays.Comment: 8 pages, 2 figures, 4 tables. Submitted to Phys. Rev. Let
Prevalence and Risk Factors of Gang Membership in a Brazilian Birth Cohort
Importance: There is no longitudinal evidence on risk factors for gang membership in low- and middle-income countries, despite organized crime groups posing major challenges, including high homicide rates in Latin America. Furthermore, adverse childhood experiences (ACEs) have been largely overlooked in gang-related research worldwide.
Objectives: To examine the associations of ACEs up to 15 years of age with past-year gang membership at 18 years of age and to compare crime and criminal justice involvement between gang members and non-gang members.
Design, setting, and participants: This cohort study assessed children from the 1993 Pelotas (Brazil) Birth Cohort-an ongoing population-based, prospective study. Assessments were undertaken perinatally (1993) and when the children were ages 11 (2004), 15 (2008), 18 (2011), and 22 (2015) years. All children born in 1993 were eligible (N = 5265), and 5249 (99.7%) were enrolled at birth. The study sample (N = 3794 [72.1%]) included those with complete data on ACEs. Data analyses were conducted from February to August 2024.
Exposures: Twelve ACEs were assessed up to 15 years of age via child self-report and/or maternal report, including physical neglect, physical abuse, emotional abuse, sexual abuse, domestic violence, maternal mental illness, parental divorce, ever being separated from parents, parental death, poverty, discrimination, and neighborhood fear. These experiences were examined using a single adversity approach, cumulative risk, and latent classes.
Main outcomes and measures: The main outcome was past-year gang membership at 18 years of age, assessed via self-report and analyzed using multivariate imputation.
Results: Of 3794 participants, 1964 (51.8%) were female and 1830 (48.2%) were male, and 703 (18.5%) were Black, 2922 (77.0%) were White, and 169 (4.5%) were coded as "other" race or ethnicity (no additional details are available to further disaggregate the other category). On the basis of the imputed data, 1.6% (SE, 0.2 percentage points) of participants reported gang membership at 18 years of age. Physical abuse (odds ratio [OR], 2.76; 95% CI, 1.27-5.98), emotional abuse (OR, 2.76; 95% CI, 1.51-5.02), domestic violence (OR, 3.39; 95% CI, 1.77-6.48), parental divorce (OR, 2.04; 95% CI, 1.17-3.54), and separation from parents (OR, 3.13; 95% CI, 1.54-6.37) were associated with an increased risk of gang membership. A dose-response association was observed, with 4 or more ACEs increasing the risk (OR, 8.86; 95% CI, 2.24-35.08). In latent class analysis, the class with child maltreatment and household challenges was associated with a higher risk of gang membership than the low-adversities class (OR, 7.10; 95% CI, 2.37-21.28). There was no robust evidence that children exposed to household challenges and social risks were at increased risk of gang membership (OR, 2.28; 95% CI, 0.46-11.25).
Conclusions and relevance: In this prospective cohort study, ACEs, particularly child maltreatment and family conflict, were associated with gang involvement when examined individually, cumulatively, and as clusters in a high-crime environment in Brazil. These findings underscore the value of integrating the ACE framework into gang-related research and the potential to reduce gang-related crime by reducing ACEs.This article is based on data from the 1993 Pelotas Birth Cohort Study conducted by the Postgraduate Program in Epidemiology at Universidade Federal de Pelotas with the collaboration of the Brazilian Public Health Association. From 2004 to 2013, the Wellcome Trust supported the 1993 Pelotas Birth Cohort Study. The European Union, the National Support Program for Centers of Excellence, the Brazilian National Research Council, and the Brazilian Ministry of Health supported previous phases of the study. The 22-year follow-up was supported by the Science and Technology Department/Brazilian Ministry of Health, with resources transferred through grant 400943/2013-1 from the Brazilian National Council for Scientific and Technological Development. Analyses were supported in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-Brasil Finance Code 001 and grant OPP1164115 from the Bill and Melinda Gates Foundation. This research was funded in whole, or in part, by grant 210735_A_18_Z from the Wellcome Trust. Dr Hammerton was supported by grant 209138/Z/17/Z from the Sir Henry Wellcome Postdoctoral Fellowship
Translucency parameter of conventional restorative glass-ionomer cements.
OBJECTIVE: To evaluate the translucency parameter (TP) and contrast ratio (CR) of different conventional restorative glass-ionomer cements (GICs). MATERIALS AND METHODS: Eighteen brands of GICs were evaluated. Five disks of each material were made following ISO 9917-1. The luminous reflectance and Central Bureau of the International Commission on Illumination parameters of disks were evaluated using a colorimeter, against backings of white and black, to obtain the translucent parameter and contrast ratio of different brands of glass-ionomer cements. The correlation between translucency parameter and contrast ratio was assessed with the Pearson correlation test. The translucent and contrast ratio parameters values were submitted to the one-way ANOVA and Tukey test for multiple comparisons (p < 0.05). RESULTS: There was a strong inverse relationship between CR and TP (r2 = 0.94, p < 0.001). The contrast ratio decreased as translucency increased. There were significant differences in TP and CR among brands (p < 0.001). CONLUSIONS: GICs exhibit different translucency and contrast ratio behavior. Some brands of GICs presented very low TP and this condition would be unacceptable for areas with esthetic demands. In addition, TP and CR showed a strong linear relationship. CLINICAL SIGNIFICANCE: The results found in this study demonstrated that the knowledge of the translucency and CR of different conventional restorative GICs is important in order to guide clinicians in the selection of restorative GICs for anterior teeth
Adjustment for time-invariant and time-varying confounders in ‘unexplained residuals’ models for longitudinal data within a causal framework and associated challenges
‘Unexplained residuals’ models have been used within lifecourse epidemiology to model an exposure measured longitudinally at several time points in relation to a distal outcome. It has been claimed that these models have several advantages, including: the ability to estimate multiple total causal effects in a single model, and additional insight into the effect on the outcome of greater-than-expected increases in the exposure compared to traditional regression methods. We evaluate these properties and prove mathematically how adjustment for confounding variables must be made within this modelling framework. Importantly, we explicitly place unexplained residual models in a causal framework using directed acyclic graphs. This allows for theoretical justification of appropriate confounder adjustment and provides a framework for extending our results to more complex scenarios than those examined in this paper. We also discuss several interpretational issues relating to unexplained residual models within a causal framework. We argue that unexplained residual models offer no additional insights compared to traditional regression methods, and, in fact, are more challenging to implement; moreover, they artificially reduce estimated standard errors. Consequently, we conclude that unexplained residual models, if used, must be implemented with great care
Histopathological findings of the kidney TrematodaParatanaisia spp. (Digenea: Eucotylidae) in cattle egret (Bubulcus ibis)
Correlation between mechanical properties and stabilization time of chemical bonds in glass-ionomer cements
Yield of comparative genomic hybridization microarray in pediatric neurology practice
OBJECTIVE: The present study investigated the diagnostic yield of array comparative genomic hybridization (aCGH) in a large cohort of children with diverse neurologic disorders as seen in child neurology practice to test whether pathogenic copy number variants (CNVs) were more likely to be detected in specific neurologic phenotypes. METHODS: A retrospective cross-sectional analysis was performed on 555 children in whom a genetic etiology was suspected and who underwent whole-genome aCGH testing between 2006 and 2012. Neurologic phenotyping was performed using hospital medical records. An assessment of pathogenicity was made for each CNV, based on recent developments in the literature. RESULTS: Forty-seven patients were found to carry a pathogenic CNV, giving an overall diagnostic yield of 8.59%. Certain phenotypes predicted for the presence of a pathogenic CNV, including developmental delay (odds ratio [OR] 3.69 [1.30–10.51]), cortical visual impairment (OR 2.73 [1.18–6.28]), dysmorphism (OR 2.75 [1.38–5.50]), and microcephaly (OR 2.16 [1.01–4.61]). The combination of developmental delay/intellectual disability with dysmorphism and abnormal head circumference was also predictive for a pathogenic CNV (OR 2.86 [1.02–8.00]). For every additional clinical feature, there was an increased likelihood of detecting a pathogenic CNV (OR 1.18 [1.01–1.38]). CONCLUSIONS: the use of aCGH led to a pathogenic finding in 8.59% of patients. The results support the use of aCGH as a first tier investigation in children with diverse neurologic disorders, although whole-genome sequencing may replace aCGH as the detection method in the future. In particular, the yield was increased in children with developmental delay, dysmorphism, cortical visual impairment, and microcephaly
Combined Tevatron upper limit on gg->H->W+W- and constraints on the Higgs boson mass in fourth-generation fermion models
Report number: FERMILAB-PUB-10-125-EWe combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg->H->W+W- in p=pbar collisions at the Fermilab Tevatron Collider at sqrt{s}=1.96 TeV. With 4.8 fb-1 of integrated luminosity analyzed at CDF and 5.4 fb-1 at D0, the 95% Confidence Level upper limit on \sigma(gg->H) x B(H->W+W-) is 1.75 pb at m_H=120 GeV, 0.38 pb at m_H=165 GeV, and 0.83 pb at m_H=200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% Confidence Level a standard-model-like Higgs boson with a mass between 131 and 204 GeV.We combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg→H→W+W- in pp̅ collisions at the Fermilab Tevatron Collider at √s=1.96 TeV. With 4.8 fb-1 of integrated luminosity analyzed at CDF and 5.4 fb-1 at D0, the 95% confidence level upper limit on σ(gg→H)×B(H→W+W-) is 1.75 pb at mH=120 GeV, 0.38 pb at mH=165 GeV, and 0.83 pb at mH=200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% confidence level a standard-model-like Higgs boson with a mass between 131 and 204 GeV.Peer reviewe
CSF neopterin and quinolinic acid are biomarkers of neuroinflammation and neurotoxicity in FIRES and other infection-triggered encephalopathy syndromes.
OBJECTIVE: Infection-triggered encephalopathy syndromes (ITES) are potentially devastating neuroinflammatory conditions. Although some ITES syndromes have recognisable MRI neuroimaging phenotypes, there are otherwise few biomarkers of disease. Early detection to enable immune modulatory treatments could improve outcomes. METHODS: We measured CSF neopterin, quinolinic acid, kynurenine and kynurenine/tryptophan ratio using a liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) system. The CSF of 18 children with ITES were compared with acute encephalitis (n = 20), and three control groups, namely epilepsy (n = 20), status epilepticus (n = 18) and neurogenetic controls (n = 20). RESULTS: The main ITES phenotypes in 18 patients were acute encephalopathy with biphasic seizures and late restricted diffusion (AESD, n = 4), febrile infection-related epilepsy syndrome (FIRES n = 4) and other ITES phenotypes. Influenza A was the most common infectious trigger (n = 5), and 50% of patients had a preceding notable neurodevelopmental or family history. CSF neopterin, quinolinic acid and kynurenine were elevated in ITES group compared to the three control groups (all p < 0.0002). The ROC (area under curve) for CSF neopterin (99.3%, CI 98.1-100) was significantly better than CSF pleocytosis (87.3% CI 76.4-98.2) (p = 0.028). Elevated CSF neopterin could discriminate ITES from other causes of seizures, status epilepticus and febrile status epilepticus (all p < 0.0002). The elevated CSF metabolites normalised during longitudinal testing in two patients with FIRES. INTERPRETATION: CSF neopterin and quinolinic acid are neuroinflammatory and excitotoxic metabolites. This CSF metabolomic inflammatory panel can discriminate ITES from other causes of new onset seizures or status epilepticus, and rapid results (4 h) may facilitate early immune modulatory therapy
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