45 research outputs found
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Evaluation of PROMETAL Technique for Application to Dies for Short Run Forgings
Manufacturing of hot forging dies required several steps such as acquisition of material
block, shaping it for machining, rough machining the cavity, heat treating, finish machining,
grinding and polishing. This process takes several months. Consequently for limited number of
parts often required in aerospace industry, forging is being replaced by direct machining of parts.
If the die lead times (administrative and manufacturing) could be reduced to weeks instead of
months, forging process will become viable for short run forgings. This paper evaluates the
PROMETAL technique for dies in forging of aluminum alloys. This evaluation includes
frictional, heat transfer and strength characterization. Isothermal and non-isothermal ring tests
together with FEM models are used to determine the interface behavior and its effect on metal
flow.Mechanical Engineerin
Nickel(II) complex based on bis-(1-(pyridin-2-yl-methyl)-benzimidazol-2-yl-methyl) ether and its utilization in the oxidation of 2-amino-4-tert-butylphenol
A mononuclear nickel(II) complex [Ni(L)2].(NO3)2.H2O is synthesized utilizing a bis-benzimidazolyl ligand (L = bis-(1-(pyridin-2-yl-methyl)-benzimidazol-2-yl-methyl)ether) and characterized by single-crystal X-ray diffraction, elemental analysis, UV-vis and IR spectroscopy. Ni(II) complex crystallizes in the tetragonal system with space group I41/a and appears to be propeller-shaped when viewed along the c-axis. The [Ni(L)2].(NO3)2 complex has been utilized for the oxidation for 2-amino-4-tert-butylphenol to 4-tert-butyl-o-benzoquinone in the presence of hydrogen peroxide and the average rate of reaction is calculated to be 63×10–7 M min–1. The presence of externally added acetate ion tends to inhibit the rate of reaction
Australia\u27s health 2000 : the seventh biennial report of the Australian Institute of Health and Welfare
Australia\u27s Health 2000 is the seventh biennial health report of the Australian Institute of Health and Welfare. It is the nation\u27s authoritative source of information on patterns of health and illness, determinants of health, the supply and use of health services, and health services costs and performance.This 2000 edition serves as a summary of Australia\u27s health record at the end of the twentieth century. In addition, a special chapter is presented on changes in Australia\u27s disease profile over the last 100 years.Australia\u27s Health 2000 is an essential reference and information source for all Australians with an interest in health
Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi
Over the course of its history, the Milky Way has ingested multiple smaller satellite galaxies1. Although these accreted stellar populations can be forensically identified as kinematically distinct structures within the Galaxy, it is difficult in general to date precisely the age at which any one merger occurred. Recent results have revealed a population of stars that were accreted via the collision of a dwarf galaxy, called Gaia–Enceladus1, leading to substantial pollution of the chemical and dynamical properties of the Milky Way. Here we identify the very bright, naked-eye star ν Indi as an indicator of the age of the early in situ population of the Galaxy. We combine asteroseismic, spectroscopic, astrometric and kinematic observations to show that this metal-poor, alpha-element-rich star was an indigenous member of the halo, and we measure its age to be 11.0±0.7 (stat) ±0.8 (sys) billion years. The star bears hallmarks consistent with having been kinematically heated by the Gaia–Enceladus collision. Its age implies that the earliest the merger could have begun was 11.6 and 13.2 billion years ago, at 68% and 95% confidence, respectively. Computations based on hierarchical cosmological models slightly reduce the above limits
Detection and Characterization of Oscillating Red Giants: First Results from the TESS Satellite
Since the onset of the "space revolution" of high-precision high-cadence photometry, asteroseismology has been demonstrated as a powerful tool for informing Galactic archeology investigations. The launch of the NASA Transiting Exoplanet Survey Satellite (TESS) mission has enabled seismic-based inferences to go full sky—providing a clear advantage for large ensemble studies of the different Milky Way components. Here we demonstrate its potential for investigating the Galaxy by carrying out the first asteroseismic ensemble study of red giant stars observed by TESS. We use a sample of 25 stars for which we measure their global asteroseimic observables and estimate their fundamental stellar properties, such as radius, mass, and age. Significant improvements are seen in the uncertainties of our estimates when combining seismic observables from TESS with astrometric measurements from the Gaia mission compared to when the seismology and astrometry are applied separately. Specifically, when combined we show that stellar radii can be determined to a precision of a few percent, masses to 5%-10%, and ages to the 20% level. This is comparable to the precision typically obtained using end-of-mission Kepler data
Shifting the limits in wheat research and breeding using a fully annotated reference genome
Introduction:
Wheat (Triticum aestivum L.) is the most widely cultivated crop on Earth, contributing about a fifth of the total calories consumed by humans. Consequently, wheat yields and production affect the global economy, and failed harvests can lead to social unrest. Breeders continuously strive to develop improved varieties by fine-tuning genetically complex yield and end-use quality parameters while maintaining stable yields and adapting the crop to regionally specific biotic and abiotic stresses.
Rationale:
Breeding efforts are limited by insufficient knowledge and understanding of wheat biology and the molecular basis of central agronomic traits. To meet the demands of human population growth, there is an urgent need for wheat research and breeding to accelerate genetic gain as well as to increase and protect wheat yield and quality traits. In other plant and animal species, access to a fully annotated and ordered genome sequence, including regulatory sequences and genome-diversity information, has promoted the development of systematic and more time-efficient approaches for the selection and understanding of important traits. Wheat has lagged behind, primarily owing to the challenges of assembling a genome that is more than five times as large as the human genome, polyploid, and complex, containing more than 85% repetitive DNA. To provide a foundation for improvement through molecular breeding, in 2005, the International Wheat Genome Sequencing Consortium set out to deliver a high-quality annotated reference genome sequence of bread wheat.
Results:
An annotated reference sequence representing the hexaploid bread wheat genome in the form of 21 chromosome-like sequence assemblies has now been delivered, giving access to 107,891 high-confidence genes, including their genomic context of regulatory sequences. This assembly enabled the discovery of tissue- and developmental stage–related gene coexpression networks using a transcriptome atlas representing all stages of wheat development. The dynamics of change in complex gene families involved in environmental adaptation and end-use quality were revealed at subgenome resolution and contextualized to known agronomic single-gene or quantitative trait loci. Aspects of the future value of the annotated assembly for molecular breeding and research were exemplarily illustrated by resolving the genetic basis of a quantitative trait locus conferring resistance to abiotic stress and insect damage as well as by serving as the basis for genome editing of the flowering-time trait.
Conclusion:
This annotated reference sequence of wheat is a resource that can now drive disruptive innovation in wheat improvement, as this community resource establishes the foundation for accelerating wheat research and application through improved understanding of wheat biology and genomics-assisted breeding. Importantly, the bioinformatics capacity developed for model-organism genomes will facilitate a better understanding of the wheat genome as a result of the high-quality chromosome-based genome assembly. By necessity, breeders work with the genome at the whole chromosome level, as each new cross involves the modification of genome-wide gene networks that control the expression of complex traits such as yield. With the annotated and ordered reference genome sequence in place, researchers and breeders can now easily access sequence-level information to precisely define the necessary changes in the genomes for breeding programs. This will be realized through the implementation of new DNA marker platforms and targeted breeding technologies, including genome editing
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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
Policy research organisations in South Asia
The aim is to broadly understand factors that have led to the rise of policy research organisations in South Asia and the kind of roles they perform. Economic liberalisation has created an increasing role for multilateral institutions in social and economic development. The research conducted by these institutions does not always meet the standards of value-neutral scientifically rigorous social science research. Many social scientists across South Asian countries feel that such institutions neither reflect local social needs nor high standards of social science research. As the policy research organisations are not necessarily autonomous, they may be influenced positively by democratisation, participation, and liberalisation
Bureaucratic thinking: A study of Block Development Officers of Rajasthan and Uttar Pradesh in India
Typescript.Bibliography: leaves [149]-160.vii, 160 l illus., graphs, tablesThis dissertation is an examination and analysis of bureaucratic perceptions towards development and democracy. It is an effort to provide greater understanding of the individual bureaucrat in his performance as an agent of change. It is also an attempt to build an empirical base for formulating meaningful propositions about Indian bureaucratic behavior. It is addressed to the following research goals: 1. To delineate the major dimensions of thinking and perceptions of the bureaucrats; 2. To place the individual bureaucrat in his work and social setting; 3. To investigate the relationship between the social background of bureaucrats and their perceptions; 4. To develop typologies of bureaucrats in the total developmental context. Data for this study were based on a survey questionnaire administered to a random sample of Block Development Officers (BDOs) of the two states of Rajasthan and Uttar Pradesh. BDOs were chosen because they are local administrators coming in direct contact with the people and political leadership. They are also important functionaries of Community Development Administration and are thus agents of change. We found that bureaucrats in our study came from a rural and parochial background and showed no evidence of elitist character. In their social aspirations, they showed a strong indication of a desire to move from rural to urban and enter the urban elite. We found that rural background did not lead to rural affinity. If given a choice, they would not join the government service again and also would not ask their children to follow them in their governmental profession. The general views of bureaucrats were marked by a widespread suspicion of the social environment and intense hostility towards the politicians. They perceive common people as lacking in ability to discern their own good and easily swayed by parochial influences. They are corruption to be rising in the villages with the advent of democracy. But the bureaucrats hold themselves in high regard and are confident that if they had power a well administered state will emerge. They display, therefore, a desire to monopolize all power in their own hands in order to be effective. We have classified such bureaucrats as 'Power Monopolizers.' BDOs are pessimistic and widely believe that there is a progressive deterioration in the general conditions and administration. We have classified these bureaucrats as 'past oriented.' Seven major dimensions of bureaucratic perceptions emerged from factor analysis. They were named Cynicism, Power Monopolizer, Decision Maker, Departmental Skepticism, Hierarchical Barriers, Democratism and Trust. From the factors of Democratism and Trust, which form one group, to the other five factors, which form a group by themselves, the wide Trust/Cynicism syndrome is tapped. Political perceptions and personal perceptions were related. Socio-cultural variables failed to predict effective variation in the above dimensions. However, we found that Technical Education and Seniority were more important predictor variables. Both canonical and regression analyses demonstrated that Negative Seniority and Cynicism, and Technical Education and Power Monopolizer were associated. We have suggested that these perceptions may be better explained by the socializing experiences of the bureaucratic institutions themselves. Discriminant analysis demonstrated that bureaucrats of Rajasthan and Uttar Pradesh differed significantly along these dimensions. Profiles showed that Rajasthan bureaucrats scored higher on Power Monopolizer dimension. This difference could be possibly due to differing career patterns, educational background and political heritage in the two states
Battling for Clean Environment Supreme Court, Technocrats and Populist Politics in Delhi
The role of Supreme Court in controlling air pollution in Delhi in the face of political contestation and government reluctance in implementing what had already long been on the statute books. Focus is given to transport vehicles and their contribution to air pollution [CSLG WP 03-01].politics, populist, court, pollution, Delhi, political, transport, vehicles, air, industries, technocrats