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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: 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 56 604 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 100 000 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 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 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 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 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
Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study
Summary
Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally.
Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies
have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of
the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income
countries globally, and identified factors associated with mortality.
Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to
hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis,
exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a
minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical
status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary
intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause,
in-hospital mortality for all conditions combined and each condition individually, stratified by country income status.
We did a complete case analysis.
Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital
diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal
malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome
countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male.
Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3).
Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income
countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups).
Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome
countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries;
p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients
combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11],
p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20
[1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention
(ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety
checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed
(ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of
parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65
[0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality.
Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome,
middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will
be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger
than 5 years by 2030
A Superior Method for Constructing Electrical Percolation Network of Nanocomposite Fibers: In Situ Thermally Reduced Silver Nanoparticles
Nanocomposite fibers, composed of conductive nanoparticles and polymer matrix, are crucial for wearable electronics. However, the nanoparticle mixing approach results in aggregation and dispersion problems. A revolutionary synthesis method by premixing silver precursor ions (silver ammonium acetate) with polyvinyl alcohol is reported here. The solvation of ions-prevented aggregation, and uniformly distributed silver nanoparticles (in situ AgNPs, 77 nm) are formed after thermal reduction (155 degrees C) without using additional reducing or dispersion agents. The conductive fiber is synthesized by the wet spinning technology. After careful optimization, flower-shaped silver nanoparticles (AgNFs, 350-450 nm) are also employed as cofillers. The addition of in situ AgNPs (9.5 vol%) to AgNFs (30 vol%) increases electrical conductivity by 1434% (2090 to 32 064 S cm(-1)) through the efficient construction of percolation networks. The in situ AgNPs provide significantly higher conductivity compared with other secondary nanoparticle fillers. The gaseous byproducts dramatically increase flexibility with a moderate compromise in tensile strength (55 MPa). The particle-free ion-level uniform mixing of silver precursors, followed by in situ reduction, would be a fundamental paradigm shift in nanocomposite synthesis.© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei
Silver nanoflowers for single-particle SERS with 10 pM sensitivity
Surface-enhanced Raman scattering (SERS) has received considerable attention as a noninvasive optical sensing technique with ultrahigh sensitivity. While numerous types of metallic particles have been actively investigated as SERS substrates, the development of new SERS agents with high sensitivity and their reliable characterization are still required. Here we report the preparation and characterization of flower-shaped silver (Ag) nanoparticles that exhibit high-sensitivity single-particle SERS performance. Ag nanoflowers (NFs) with bud sizes in the range 220-620 nm were synthesized by the wet synthesis method. The densely packed nanoscale petals with thicknesses in the range 9-22 nm exhibit a large number of hot spots that significantly enhance their plasmonic activity. A single Ag NF particle (530-620 nm) can detect as little as 10(-11) M 4-mercaptobenzoic acid, and thus provides a sensitivity three orders of SERS magnitude greater than that of a spherical Ag nanoparticle. The analytical enhancement factors for single Ag NF particles were found to be as high as 8.0 x 10(9), providing unprecedented high SERS detectivity at the single particle level. Here we present an unambiguous and systematic assessment of the SERS performances of the Ag NFs and demonstrate that they provide highly sensitive sensing platforms by single SERS particle. © 2017 IOP Publishing Ltd Printed in the UK1341sciescopu
Hierarchically-structured silver nanoflowers for highly conductive metallic inks with dramatically reduced filler concentration
Silver has long been employed as an electrically conductive component, and morphology-dependent properties have been actively investigated. Here we present a novel scalable synthesis method of flower-shaped silver nanoparticles (silver nanoflowers, Ag NFs). The preferential affinity of citrate molecules on (111) surface of silver enabled spontaneous anisotropic growth of Ag NFs (bud size:250~580 nm, single crystalline petal thickness: 9~22 nm) with high reproducibility and a high yield of >99.5%. The unique hierarchical structure resulted in coalescence of petals over 80~120 °C which was practically employed in conductive inks to construct percolation pathways among Ag NFs. The ink with only 3 wt% of Ag NFs provided two orders of magnitude greater conductivity (1.008 × 105 Scm−1), at a low curing temperature of 120 °C, compared with the silver nanoparticle ink with a much higher silver concentration (50 wt%). This extraordinary property may provide an excellent opportunity for Ag NFs for practical applications in printable and flexible electronics. © The Author(s) 20161351sciescopu
In-situ reduced non-oxidized copper nanoparticles in nanocomposites with extraordinary high electrical and thermal conductivity
© 2021 Elsevier Ltd. Copper has received considerable attention for conductive nanocomposites as an alternative to costly silver or gold. However, practical application has been impeded by its susceptibility to oxidation in air. Here we report a novel scalable synthesis method of non-oxidized copper nanoparticles (InSituCuNPs) by pre-mixing and in-situ reducing copper formate-(butylamine-octylamine) complex inside soft epoxy matrix. The solid–liquid phase change of the copper formate complex, during the nanocomposite spark-plasma-sintering process, promotes uniform dispersion. Even the outermost atoms of InSituCuNPs are not oxidized since they are surrounded by the thick matrix polymer as soon as in-situ reduced into metallic copper, resulting in high electrical (15,048 Scm−1) and thermal (28.4 Wm−1K−1) conductivities of the nanocomposite. Furthermore, a small addition of 1-dimensional carbon nanotubes decorated with 0-dimensional copper nanoparticles (<4 nm), together with bi-functionalization, dramatically enhances connectivity between the InSituCuNPs, resulting in air-stable and record-high 31,974 Scm−1 and 74.1 Wm−1K−1 for isotropic copper-based nanocomposites. The nanocomposite also provides a small thermal resistance (2.64 × 10−6 m2KW−1) and excellent heat dissipation performance.11Nsciescopu
Evaluation Of Post Traumatic Stress Disorder And Its Complications
Post-traumatic stress disorder (PTSD) remains a widespread mental health challenge with profound consequences for people exposed to traumatic events. This review provides a comprehensive and critical appraisal of recent research on PTSD and sheds light on the complexities of its diagnosis, etiology, and treatment. The review includes a comprehensive analysis of the various methods used in PTSD research, including neurobiological, psychological, and sociocultural perspectives. It examines the impact of evolving diagnostic criteria and emphasizes the need to understand the nuances of symptoms and their heterogeneity in different populations. In addition, this summary discusses complications associated with PTSD research, such as comorbidities, cultural variations, and the influence of genetic factors. The interaction between trauma severity, resilience factors and the likelihood of developing chronic PTSD is explored, providing insight into the different trajectories observed in affected individuals.
The review also discusses advances in therapeutic interventions, from traditional psychotherapeutic approaches to new pharmacological and neuromodulatory strategies. Special attention is given to the challenges of implementing evidence-based treatment and the need to tailor individualized treatments tailored to the unique needs of PTSD patients. Together, this summary summarizes the current state of PTSD research, highlights gaps in knowledge, and suggests avenues for future research. The complexity of PTSD research requires a multidimensional approach that integrates biological, psychological and sociocultural factors, ultimately contributing to a more comprehensive understanding of the disorder and improved treatment outcomes.
 
Non-oxidized bare copper nanoparticles with surface excess electrons in air
© 2022 Springer Nature Limited. Copper (Cu) nanoparticles (NPs) have received extensive interest owing to their advantageous properties compared with their bulk counterparts. Although the natural oxidation of Cu NPs can be alleviated by passivating the surfaces with additional moieties, obtaining non-oxidized bare Cu NPs in air remains challenging. Here we report that bare Cu NPs with surface excess electrons retain their non-oxidized state over several months in ambient air. Cu NPs grown on an electride support with excellent electron transfer ability are encapsulated by the surface-accumulated excess electrons, exhibiting an ultralow work function of ~3.2 eV. Atomic-scale structural and chemical analyses confirm the absence of Cu oxide moiety at the outermost surface of air-exposed bare Cu NPs. Theoretical energetics clarify that the surface-accumulated excess electrons suppress the oxygen adsorption and consequently prohibit the infiltration of oxygen into the Cu lattice, provoking the endothermic reaction for oxidation process. Our results will further stimulate the practical use of metal NPs in versatile applications.11Nsciescopu