222 research outputs found
Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC
Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990â2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56â604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100â000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100â000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100â000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100â000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100â000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Stillbirths among Advanced Maternal Age Women in the United States: 2003-2017
The aim of the study was to evaluate the association between fetal stillbirth and advanced maternal age in the United States (US). This was a population-based study using the Natality and Fetal Death datasets for the years 2003-2017. We built Cox proportional regression models to examine the likelihood of stillbirth among women aged ?40 years. Out of a total of 57,273,305 births, stillbirth was observed in 302,522, yielding a stillbirth rate of 5 per 1000. After adjusting for confounders, women of advanced age (?40 years) had a 40-50% greater risk of stillbirth compared to women 20-29 years of age.
Keywords: âą Advanced maternal age âą Stillbirth âą Cox proportional regression âą United States
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Copyright © 2020 Dongarwar et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Trends in Stillbirths and Stillbirth Phenotypes in the United States: An Analysis of 131.5 Million Births
We examined the trends in stillbirth across gestational age in the United States (US).We conducted a trend analysis using the U.S. Natality and Fetal Death datasets covering 1982 and 2017. We compared the incidence and rates of stillbirth for term, all preterm, moderate-to-late preterm, very preterm, and extreme preterm phenotypes. The incidence of stillbirth decreased for the entire birth cohort over the 36-year period. The rates of overall, term, all preterm, very preterm and moderate-to-late preterm stillbirth decreased from 1982 to 2017; however, the rates for extreme preterm stillbirth increased by about 7.6% over the same study period.
Key words: âą Trends in stillbirth âą Stillbirth phenotypes âą Stillbirth in US
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Copyright © 2020 Dongarwar et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Evaluation of an Evidence-based and Community-responsive Fatherhood Training Program: Providersâ Perspective
Background And Objectives: Studies on male involvement and pregnancy outcomes have often not incorporated the providersâ perspectives, which are potentially critical to understanding program context, evolution, perceived impact, and sustainability. We sought to evaluate the 24/7 DadÂź program from the viewpoint of the program providers.
Methods: We conducted purposive sampling of 24/7 Dad program facilitators and administrators who were involved in recruitment, training, and follow up of program participants within a federal Healthy Start program (REACHUP) in Tampa, Florida, USA. Using a snowballing approach, we recruited six key informants who had administered the program for at least four years. We elicited and evaluated factors impacting the performance of the father involvement program using content analysis.
Results: Under program participation and perceived impact, most providers thought that the program had created a safe space previously unavailable for men in the community. The most useful recruitment strategy was building partnerships with other organizations. The key informants noted an important evolutionary trend in the father involvement program over time as well as the nature of linkages to partner organizations within the area. Threats to program sustainability included the continued reluctance and scepticism to invest funds to address male issues, sub-optimal retention of participants who were living transient lives as well as geographical/transportation barriers.
Conclusion and Global Health Implications: The involvement of fathers during pregnancy has significant implications for healthy babies. Our study results provide a clarion call to augment capacity and infuse more resources to improve paternal involvement in order to attain the United Nations Sustainable Goal (2015-2030) of ensuring healthy lives and the promotion of well-being for all at all ages.
Key words: âą Fatherhood involvement âą Fatherhood training âą REACHUP âą Childhood development âą 24/7 Dad program
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Copyright © 2020 Obure et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Multiplicity dependence of light (anti-)nuclei production in pâPb collisions at sNN=5.02 TeV
The measurement of the deuteron and anti-deuteron production in the rapidity range â1 < y < 0 as a function of transverse momentum and event multiplicity in pâPb collisions at âsNN = 5.02 TeV is presented. (Anti-)deuterons are identified via their specific energy loss dE/dx and via their time-of- flight. Their production in pâPb collisions is compared to pp and PbâPb collisions and is discussed within the context of thermal and coalescence models. The ratio of integrated yields of deuterons to protons (d/p) shows a significant increase as a function of the charged-particle multiplicity of the event starting from values similar to those observed in pp collisions at low multiplicities and approaching those observed in PbâPb collisions at high multiplicities. The mean transverse particle momenta are extracted from the deuteron spectra and the values are similar to those obtained for p and particles. Thus, deuteron spectra do not follow mass ordering. This behaviour is in contrast to the trend observed for non-composite particles in pâPb collisions. In addition, the production of the rare 3He and 3He nuclei has been studied. The spectrum corresponding to all non-single diffractive p-Pb collisions is obtained in the rapidity window â1 < y < 0 and the pT-integrated yield dN/dy is extracted. It is found that the yields of protons, deuterons, and 3He, normalised by the spin degeneracy factor, follow an exponential decrease with mass number
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