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

Microstructure and Optical Properties of Zn(O,S) Thin Films Prepared by Radio Frequency Magnetron Sputtering

銅銦鎵硒太陽電池為未來各類薄膜太陽能電池中最具發展潛力的材料之一，然而目前高效率的CIGS太陽能電池仍以水浴法所製備的硫化鎘作為主要緩衝層材料，為減少使用鎘離子對環境造成的隱憂，以及產業化的應用考量，尋找無鎘化緩衝層材料和全真空製程將是發展CIGS太陽能電池產業需要克服的議題之一。 本研究主要是利用射頻磁控濺鍍系統沉積硫氧化鋅薄膜，研究改變不同的射頻濺鍍功率、氬氧混合氣體的氧分率和基板溫度，探討薄膜的微結構與光學特性。在固定基板溫度473K和氧分率2%下，探討射頻功率對薄膜的影響；隨著射頻功率的增加，(002)繞射峰往低角度偏移，同時可以發現硫氧化鋅薄膜為一HCP的結構。電子能譜的定量分析可以發現，隨著功率增加氧含量由12.63 at%下降至7.61 at%，而硫含量由35.98 at.%上升至40.71 at%，UV/VIS分析得知之光吸收邊緣由4.12 eV偏移至3.88 eV，亦即射頻功率增加能隙有一紅移現象。 在固定基板溫度473K和射頻功率175W下，探討通入氣體氧分率對薄膜的影響。隨著氧分率超過4%後，所產生的薄膜為一非晶結構，由對薄膜的定量分析得知隨著氧分率增加，氧含量由10.79 at%提升至62.31 at%，而硫含量由40.35 at%下降至4.55 at%，其光吸收邊緣由4.03 eV偏移至4.17 eV，即氧分率增加能隙有一藍移現象。 而在固定射頻功率和氧分率4%下，探討改變基板溫度對薄膜的影響。由X光晶體繞射分析發現隨著基板溫度增加，(002)繞射峰往高角度偏移；由TEM的選區繞射確定為HCP結構，而光學吸收邊緣波長隨著基板溫度增加由4.10 eV偏移至4.03 eV，亦即基板溫度增加能隙有一紅移現象。Cu(In,Ga)Se (CIGS) solar cell is one of most promising material in thin film solar cell. The chemical bath deposition CdS is typically used as buffer layer in high efficiency solar cell. However, Cd is very toxic and taken consideration in great impact to environment. It is quite important issue for mass production to search Cd-free alternated buffer layer and develop all-vacuum process in the future. A series of ZnO1−xSx films prepared by radio-frequency reactive magnetron sputtering on soda-lime glasses as substrates. The composition, structure, and optical properties of the films deposited at different RF power, O2/(Ar+O2) ratio and substrate temperature were studied. The structure of the films deposited under various process parameters was characterized by XRD revealed that the films are wurtzite structure. The XRD peak shift to lower angle position with increasing RF power. The layer composition show that oxygen concentration decrease from 12.63 to 7.61 at.% and sulfur increase from 35.98 to 40.71 at.% as RF power increases. The optical absorption edge shift from 4.12 to 3.88 eV (red shift effect). Amorphous structure was found as O2/(Ar+O2) excess 4%. ESCA show the content of oxygen increase from 10.79 to 62.31 at.% and sulfur decrease from 40.35 to 4.55 at.% with oxygen flow increase. The optical transmission spectra show absorption edge shift 4.03 to 4.17 eV (blue shift effect). The XRD peak shift to higher angle was observed as substrate temperature increased. From TEM observation, the films were wurtzite structure with (002) preferred orientation. The optical absorption edge shift from 4.10 to 4.03 eV (red shift effect).摘要I AbstractII 目次III 圖目次IV 表目次VI 第一章 緒論1 1.1 前言1 1.2 太陽能電池原理2 1.2.1 太陽能電池照光特性3 1.2.2 量子效率5 1.2.3 短路電流與開路電壓6 1.2.4 填充因子與轉換效率7 1.2.5 太陽能電池的等效電路8 1.2.6 太陽能電池的串聯電阻與並聯電阻9 1.3 銅銦鎵硒太陽能電池發展史12 1.4 研究動機與目的13 第二章 文獻回顧14 2.1 反應射頻濺鍍原理14 2.1.1 電漿理論14 2.1.2 薄膜沉積機制16 2.1.3 濺鍍薄膜微結構分佈情形20 2.2 氧化鋅與硫化鋅結構特性22 2.3 緩衝層24 2.4 硫化鎘緩衝層26 2.5 硫化銦緩衝層27 2.6 氧化鎂鋅緩衝層30 2.7 硫化鋅緩衝層33 第三章 實驗方法與步驟37 3.1 試片前處理37 3.2 緩衝層設計37 3.3 材料分析37 3.4 實驗流程38 3.5 研究之製程設備39 3.6 研究之分析儀器40 第四章 結果與討論42 4.1 功率變化對薄膜性質影響42 4.1.1 晶體繞射分析42 4.1.2 化學分析電子能譜儀46 4.1.3 穿透率與能隙49 4.1.4 掃描式電子顯微鏡分析52 4.2 氧分率變化對薄膜性質影響54 4.2.1 晶體結構繞射分析54 4.2.2 化學分析電子能譜儀57 4.2.3 穿透率與能隙59 4.2.4 掃描式電子顯微鏡分析62 4.3 溫度變化對薄膜性質的影響64 4.3.1 晶體結構繞射分析64 4.3.2 穿透率與能隙67 4.3.3 掃描式電子顯微鏡分析69 第五章 結論71 參考書目7

Enhanced performance of proton exchange membrane fuel cells by Pt/carbon/antimony-doped tin dioxide triple-junction catalyst

Abstract A composite material comprising carbon black and Sb-doped SnO2 (ATO) is employed as a support for a Pt catalyst in a membrane electrode assembly (MEA) to improve the performance of a proton-exchange membrane fuel cell under low-humidity conditions. The effects of Sb-doping on the crystal, structural, and electrochemical characteristics of ATO particles are being examined. In a single cell test, the ratio of Sb in ATO is systematically optimized to improve performance. The distribution of Pt nanoparticles is uniform on carbon black and ATO carrier, forming notable triple-junction points at the interface of carbon black and ATO carrier. This structure thus induces a strong interaction between Pt and ATO, promoting the content of metallic Pt. Compared with a Pt/C catalyst, the best-performing Pt/C–ATO catalyst exhibits superior electrochemical activity, stability, and CO tolerance. The power density of MEA with the Pt/C–ATO catalyst is 15% higher than that of the MEA with the Pt/C catalys

Phase transformation and dielectric properties of sputtering-prepared Zn-Ti-O thin films

Zn–Ti–O films were co-sputtered from Zn and Ti targets and then annealed at temperatures ranging from 600 °C to 900 °C for 2 h under an air atmosphere. The [Ti]/([Ti]+[Zn]) ratio decreased from 75.52 to 28.26 as the Zn-target power increased from 25 W to 75 W. The phase transition of the films strongly depended on the [Ti]/([Ti]+[Zn]) ratio. High [Ti]/([Ti]+[Zn]) ratios led to the coexistence of ZnTiO3, Zn2Ti3O8, and rutile TiO2 phases. Zn2Ti3O8 gradually became the major crystalline phase as the [Ti]/([Ti]+[Zn]) ratio and rutile TiO2 and ZnTiO3 phases decreased. The aforementioned phases disappeared when the [Ti]/([Ti]+[Zn]) ratio was especially low. In their place, Zn2TiO4 and even ZnO phases developed. The dielectric constant of the films increased with increasing [Ti]/([Ti]+[Zn]) ratio. However, extremely high [Ti]/([Ti]+[Zn]) ratios increased the dielectric loss of the films. The film mainly composed of the Zn2Ti3O8 phase exhibited optimal dielectric properties, including a dielectric constant and loss equal to 40.1 and 0.0304, respectively, at 1 MHz

Structural and mechanical properties of magnetron sputtered Ti–V–Cr–Al–N films

Ti–V–Cr–Al–N films were prepared by dc magnetron co-sputtering by utilizing TiVCr and Al targets. By using glancing incidence X-ray diffraction, a single NaCl solid solution phase with (2 0 0) preferred orientation for the Al-doped films was revealed, as opposed to the undoped films that possessed predominantly (1 1 1) preferred orientation. This indicates that Al addition can lead to the enhancement of adatom mobility and consequently, to a thermodynamically favorable (2 0 0) orientation. This also leads to grain growth and increased surface roughness. However, based on results from transmission electron microscopy, the microstructure morphology seemed independent of the Al concentration, implying that adatom mobility is not sufficient for the barriers present at the grain boundaries. Accordingly, hardness was enhanced by the increase in Al concentration

Structural morphology and characterization of (AlCrMoTaTi)N coating deposited via magnetron sputtering

(AlCrMoTaTi)N coatings were deposited on Si substrates via reactive magnetron sputtering. The effects of N2-to-total (N2 + Ar) flow ratio (RN) on the coating structure and properties were examined. Alloy coatings have composite equiaxed grain structures consisting of amorphous and body-centered cubic crystal phases, whereas nitride coatings have columnar structures with single face-centered cubic crystal phase. Distinct lattice expansion and grain refinement were observed in nitride coatings as RN increased. Typical V-shaped columnar structures with faceted tops and open column boundaries transformed into denser and smaller columnar structures with domed surfaces. Increasing RN to 30% caused the hardness and modulus to reach maximum values of 30.6 and 291.6 GPa, respectively. Electrical resistivity increased from 536 μΩ cm to 8212 μΩ cm when RN increased from 10% to 50%

Influence of chemical composition on phase transformation and optoelectronic properties of Cu-Cr-O thin films by reactive magnetron sputtering

Cu–Cr–O films were co-sputtered from Cu and Cr targets on fused silica substrates. Then, these films were annealed at 700 °C for 2 h under controlled Ar atmosphere. [Cu]/[Cr] ratio was increased from 0.59 to 2.02 by increasing the Cu-target power from 10 W to 52 W. When the film was prepared at Cu-target power of 10 W, a pure spinel CuCr2O4 phase was formed in the film. As the Cu-target power increased to 22 W, the phase transformed gradually from spinel CuCr2O4 to delafossite CuCrO2. Further increase of Cu-target power resulted in the appearance of an additional monoclinic CuO phase. The [Cu]/[Cr] ratio was approximately 1 at Cu-target power of 22 W, which caused the film to exhibit pure delafossite CuCrO2 phase and high crystallinity. Accordingly, optimum electrical conductivity and visible transparency were achieved for the pure CuCrO2 film prepared at Cu-target power of 22 W with a figure of merit of 1.51 × 10−8 Ω−1. The formation of the CuO and CuCr2O4 phase was confirmed to deteriorated optoelectronic properties of films