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Atmospheric oxygen (O2) is one of the predominant features that enable Earth as a habitable planet for active and diverse biology. However, observations since the late 1980s indicate that O2 content in the atmosphere is falling steadily at part-per-million level. Although a scientific consensus has emerged that the current decline is generally attributed to the combustion of fossil fuel, a quantitative assessment of the anthropogenic impact on the O2 cycle on both global and regional scale is currently lacking. This paper quantifies the anthropogenic and biological O2 flux over land and provides a quantitative and dynamic description of land O2 budget under impacts of human activities on grid scale. It is found that total anthropogenic O2 flux over land has risen from 35.6 Gt/yr in 2000 to 46.0 Gt/yr in 2013, while the compensation from land (11.5 Gt/yr averaged from 2000 to 2013) displays a faint increase during the same period. High anthropogenic fluxes mainly occur in Eastern Asia, India, North America and Europe caused by fossil fuel combustion and in Central Africa caused by wildfire. Due to strong heterotrophic soil respiration under higher temperature conditions, the positive O2 flux in the tropics is not significant. Instead, boreal forest and Tibetan plateau become the most important sources of atmospheric O2 in the Anthropocene. [ABSTRACT FROM AUTHOR]

This study investigated the places of origin of international students and their distribution in the United States higher education. The data concerning the population of international students were obtained from the official website of International Institution of Education (IIE), and transferred into three maps using geographic information systems (GIS) software so that a more direct view of the data was available. The results of the study showed that (1) A larger proportion of international students come from Asian countries; (2) California, New York, and Texas are the top three states hosting international students; (3) most of the universities enrolling international students are located in the eastern part of the country; and (4) the states with already large international student populations experienced a faster growth in the population of international students over the past five years. Some implications for policy planning are discussed at the end of this paper.

The paper examines trends and issues in digital education programmes globally, drawing examples of developmental growth of Library Information Science (LIS), schools and digital education courses in North America, Britain, and Southern Asia, the slow growth of LIS schools and digital education in Nigeria and some countries in Africa and India. The literature so far visited dictated problems of inadequacy in digital education globally to dearth of faculty, training facilities, no collaboration among LIS schools in developing countries, encouraging collaborations in developed countries and not many students attracted to the course. Recommended solutions are suggested for attracting students into the programme and what to do to make it competitive like other programmes in the universities.

In this work we couple the HTAP_v2.2 global air pollutant emission inventory with the global source receptor model TM5-FASST to evaluate the relative contributions of the major anthropogenic emission sources (power generation, industry, ground transport, residential, agriculture and international shipping) to air quality and human health in 2010. We focus on particulate matter (PM) concentrations because of the relative importance of PM 2.5 emissions in populated areas and the well-documented cumulative negative effects on human health. We estimate that in 2010, depending on the region, annual averaged anthropogenic PM 2.5 concentrations varied between ca. 1 and 40 µ g m -3 , with the highest concentrations observed in China and India, and lower concentrations in Europe and North America. The relative contribution of anthropogenic emission sources to PM 2.5 concentrations varies between the regions. European PM pollution is mainly influenced by the agricultural and residential sectors, while the major contributing sectors to PM pollution in Asia and the emerging economies are the power generation, industrial and residential sectors. We also evaluate the emission sectors and emission regions in which pollution reduction measures would lead to the largest improvement on the overall air quality. We show that air quality improvements would require regional policies, in addition to local- and urban-scale measures, due to the transboundary features of PM pollution. We investigate emission inventory uncertainties and their propagation to PM 2.5 concentrations, in order to identify the most effective strategies to be implemented at sector and regional level to improve emission inventories, knowledge and air quality modelling. We show that the uncertainty of PM concentrations depends not only on the uncertainty of local emission inventories, but also on that of the surrounding regions. Countries with high emission uncertainties are often impacted by the uncertainty of pollution coming from surrounding regions, highlighting the need for effective efforts in improving emissions not only within a region but also from extra-regional sources. Finally, we propagate emission inventory uncertainty to PM concentrations and health impacts. We estimate 2.1 million premature deaths per year with an uncertainty of more than 1 million premature deaths per year due to the uncertainty associated only with the emissions. [ABSTRACT FROM AUTHOR]

Background: The use of early morning sputum samples (EMS) to diagnose tuberculosis (TB) can result in treatment delay given the need for the patient to return to the clinic with the EMS, increasing the chance of patients being lost during their diagnostic workup. However, there is little evidence to support the superiority of EMS over spot sputum samples. In this new analysis of the REMoxTB study, we compare the diagnostic accuracy of EMS with spot samples for identifying Mycobacterium tuberculosis pre- and post-treatment.Methods: Patients who were smear positive at screening were enrolled into the study. Paired sputum samples (one EMS and one spot) were collected at each trial visit pre- and post-treatment. Microscopy and culture on solid LJ and liquid MGIT media were performed on all samples; those missing corresponding paired results were excluded from the analyses.Results: Data from 1115 pre- and 2995 post-treatment paired samples from 1931 patients enrolled in the REMoxTB study were analysed. Patients were recruited from South Africa (47%), East Africa (21%), India (20%), Asia (11%), and North America (1%); 70% were male, median age 31 years (IQR 24-41), 139 (7%) co-infected with HIV with a median CD4 cell count of 399 cells/μL (IQR 318-535). Pre-treatment spot samples had a higher yield of positive Ziehl-Neelsen smears (98% vs. 97%, P = 0.02) and LJ cultures (87% vs. 82%, P = 0.006) than EMS, but there was no difference for positivity by MGIT (93% vs. 95%, P = 0.18). Contaminated and false-positive MGIT were found more often with EMS rather than spot samples. Surprisingly, pre-treatment EMS had a higher smear grading and shorter time-to-positivity, by 1 day, than spot samples in MGIT culture (4.5 vs. 5.5 days, P < 0.001). There were no differences in time to positivity in pre-treatment LJ culture, or in post-treatment MGIT or LJ cultures. Comparing EMS and spot samples in those with unfavourable outcomes, there were no differences in smear or culture results, and positive results were not detected earlier in Kaplan-Meier analyses in either EMS or spot samples.Conclusions: Our data do not support the hypothesis that EMS samples are superior to spot sputum samples in a clinical trial of patients with smear positive pulmonary TB. Observed small differences in mycobacterial burden are of uncertain significance and EMS samples do not detect post-treatment positives any sooner than spot samples. [ABSTRACT FROM AUTHOR]

"The post-mid-1970's picture of international migration from India...gives the impression that its 'brain drain' to the developed countries of the West, particularly the U.S.A. declined.... The impression was also consolidated by changes in the American Immigration Law wherein the emphasis had seemingly shifted from the 'occupational usefulness' of the immigrants in the American labour market to their 'family reunification.'.... The paper argues that human capital transfers through migration from India [have] not abated simply because of immigration under the 'occupational preference' categories. Rather what happened is that the brain drain has continued through alternative channels...." (SUMMARY IN FRE AND SPA), (excerpt)