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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
Reduction of Nitrous Oxide by Light Alcohols Catalysed by a Low-Valent Ruthenium Diazadiene Complex
Decomposition of the environmentally harmful gas nitrous oxide (N2O) is usually performed thermally or catalytically. Selective catalytic reduction (SCR) is currently the most promising technology for N2O mitigation, a multicomponent heterogeneous catalytic system that employs reducing agents such as ammonia, hydrogen, hydrocarbons, or a combination thereof. This study reports the first homogenous catalyst that performs the reduction of nitrous oxide employing readily available and cheap light alcohols such as methanol, ethanol or ethylene glycol derivatives. During the reaction, these alcohols are transformed in a dehydrogenative coupling reaction to carboxylate derivatives, while N2O is converted to N-2 and H2O, later entering the reaction as substrate. The reaction is catalysed by the low-valent dinuclear ruthenium complex [Ru2H(mu-H)(Me(2)dad)(dbcot)(2)] that carries a diazabutadiene, Me(2)dad, and two rigid dienes, dbcot, as ligands. The reduction of nitrous oxide proceeds with low catalyst loadings under relatively mild conditions (65-80 degrees C, 1.4 bar N2O) achieving turnover numbers of up to 480 and turnover frequencies of up to 56 h(-1).ISSN:0947-6539ISSN:1521-376
Regioselective Rhodium‐Catalyzed 1,2‐Hydroboration of Pyridines and Quinolines Enabled by the Tris(8‐quinolinyl)phosphite Ligand**
A Rh(I) complex [κ2(P,N)-{P(Oquin)3}RhCl(PPh3)] (1) bearing the P,N ligand tris(8-quinolinyl)phosphite, P(Oquin)3, has been synthesized and structurally characterized. The molecular structure of complex 1 shows that P(Oquin)3 acts as a bidentate P,N chelate ligand. Reactivity studies of 1 reveal that the triphenylphosphine ligand can be replaced by Pcy3 or removed upon oxidation with concomitant coordination of a second 8-quinolyl unit of P(Oquin)3. In addition, the Rh(III) complex [RhCl2{OP(Oquin)2}] (3), resulting from treating 1 with either wet CDCl3 or, sequentially, with HCl and water, was identified by X-ray diffraction analysis. Complex 1 catalyzes the 1,2-regioselective hydroboration of pyridines and quinolines, affording N-boryl-1,2-dihydropyridines (1,2-BDHP) and N-boryl-1,2-hydroquinolines (1,2-BDHQ) in high yield (up to >95 %) with turnover numbers (TONs) of up to 130. The system tolerates a variety of substrates of different electronic and steric nature. In comparison with other transition-metal-based hydroboration catalysts, this system is efficient at a low catalyst loading without the requirement of base or other additives
Propuesta de documentación de un sistema de gestión de la calidad para los procesos de diseño, realización y comercialización en MEDDEX SA de CV.
Tesis (Licenciatura en Administración Industrial), Instituto Politécnico Nacional, UPIICSA, 2010, 1 archivo PDF, (101 páginas). tesis.ipn.m
Insights into metal-ligand hydrogen transfer: A square-planar ruthenate complex supported by a tetradentate amino-amido-diolefin ligand
A four-coordinate, sixteen-electron Ru(0) complex containing the tetradentate diamino-diolefin ligand (±)-trans-N,N-bis(5H-dibenzo[a,d]cyclohepten-5-yl)-1,2-diaminocyclohexane (trop2dach) has been synthesised. Deprotonation of one amino N–H functional group generates an unprecedented four-coordinate ruthenate species which has been characterised in solution and in the solid state. The newly formed ruthenate complex undergoes intramolecular metal–ligand N–H addition/elimination in solution to generate a transient diamido ruthenium hydride species, as supported by NMR spectroscopy and density functional theory.ISSN:1359-7345ISSN:1364-548
CCDC 1520289: Experimental Crystal Structure Determination
KECFOQ : (2,2'-bipyridine)-(bis(5H-dibenzo[a,d][7]annulen-5-yl)amide)-cobalt hexafluorophosphate Space Group: P 21/n (14), Cell: a 10.6753(7)Å b 17.1784(11)Å c 17.6350(12)Å, α 90.00° β 94.2410(10)° γ 90.00° Related Article: Rafael E. Rodríguez-Lugo, Bas de Bruin, Monica Trincado and Hansjörg Grützmacher|2017|Chem.-Eur.J.|23|6795|doi:10.1002/chem.201605624,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1520295: Experimental Crystal Structure Determination
KECFUW : (2,2'-bipyridine)-(bis(5H-dibenzo[a,d][7]annulen-5-yl)amide)-cobalt cyclohexane hexane solvate Space Group: P 1 (2), Cell: a 11.9983(15)Å b 12.4860(15)Å c 24.705(3)Å, α 99.662(2)° β 98.028(2)° γ 109.760(2)° Related Article: Rafael E. Rodríguez-Lugo, Bas de Bruin, Monica Trincado and Hansjörg Grützmacher|2017|Chem.-Eur.J.|23|6795|doi:10.1002/chem.201605624,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 1520288: Experimental Crystal Structure Determination
KECFIK : (2,2'-bipyridine)-(bis(5H-dibenzo[a,d][7]annulen-5-yl)amine)-cobalt hexafluorophosphate 1,2-dimethoxyethane solvate Space Group: P 21/c (14), Cell: a 35.2780(5)Å b 17.6354(2)Å c 18.7703(2)Å, α 90.00° β 97.1890(10)° γ 90.00° Related Article: Rafael E. Rodríguez-Lugo, Bas de Bruin, Monica Trincado and Hansjörg Grützmacher|2017|Chem.-Eur.J.|23|6795|doi:10.1002/chem.201605624,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Speciation study and biological activity of copper (II) complexes with picolinic and 6-methylpicolinic acid with different components of blood serum of low molecular mass in KNO3 1.0 mol·L−1 at 25 °C
In the present work, the chemical speciation of ternary complexes of copper (II) with picolinic acid and 6-methylpicolinic acid and different ligands, such as, components of the blood plasma of low molecular mass (lactic acid, oxalic acid, citric acid, and phosphoric acid) were studied by measurements of emf(H) in KNO3 1.00 molL- 1. Potentiometric studies showed a predilection towards the formation of ternary species in solution, except for the copper (II)-picolinate-phosphate systems. The biological activity of the binary and ternary complexes isolated in situ, against reactive oxygen species was studied showing a concentration-dependent effect due to a possible mechanism of electron transfer. Finally, for the complexes Cu(Pic)2 and for the ligands were studied the ligand-receptor interaction on a PI3k of human origin by molecular docking, showing that, by themselves, the ligands are not capable of interacting with the active site of the enzyme. The metallic center is fundamental to generate reversible electrostatic interactions, that can be key to the indirect hypoglycemic effect exhibited by the Cu(Pic)2 complex reported in the literature