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81.
Mohammad Iqbal Hossain Sultana Parvin Md. Samiul Islam Mohammad Jane Alam Subrata Podder Raj Datta Touhidul Karim Majumdar Mir Jakib Hossain Faruque Ahmed 《Medicine》2021,100(37)
In December 2019, with pneumonia-like clinical manifestations, a new severe acute respiratory syndrome coronavirus 2 emerged and quickly escalated into a pandemic. Since the first case detected in early March of last year, 8668 have died with an infection mortality rate of 1.52%, as of March 20, 2021. Bangladesh has been struck by the 2nd wave from mid-march 2021. As data on the second wave are sparse, the present study observed the demographic profile, symptoms, and outcomes of Coronavirus Disease 2019 (COVID-19) patients during this wave.The study was conducted at Sheikh Russel National Gastroliver Institute on 486 admitted cases during the 2nd wave of COVID-19 in Bangladesh (March 24–April 24, 2021) using a cross-sectional study design and a convenient sampling technique.Out of 486 cases, 306 (62.9%) were male, and 180 were female, with a mean age of 53.47 ± 13.86. The majority of patients (32.5%) were between the ages of 51 and 60. While fever and cough being the predominant symptoms (>70% cases), the most common co-morbidities were hypertension (41.4) and diabetes mellitus (39.4). Intensive care unit utilization rate was 25%, and a half of the patients had 51% to 70% tomographic lung involvement with an overall mortality rate of 19.3%. Older age, chronic renal disease, percentage of lung involvement, and intensive care unit necessity were important mortality determinants.The present study gives an insight into the demographic profiles and outcomes of admitted patients with COVID-19 during the second wave at a covid dedicated hospital in Bangladesh. 相似文献
82.
Benjamin M. Van Doren David E. Willard Mary Hennen Kyle G. Horton Erica F. Stuber Daniel Sheldon Ashwin H. Sivakumar Julia Wang Andrew Farnsworth Benjamin M. Winger 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(24)
Millions of nocturnally migrating birds die each year from collisions with built structures, especially brightly illuminated buildings and communication towers. Reducing this source of mortality requires knowledge of important behavioral, meteorological, and anthropogenic factors, yet we lack an understanding of the interacting roles of migration, artificial lighting, and weather conditions in causing fatal bird collisions. Using two decades of collision surveys and concurrent weather and migration measures, we model numbers of collisions occurring at a large urban building in Chicago. We find that the magnitude of nocturnal bird migration, building light output, and wind conditions are the most important predictors of fatal collisions. The greatest mortality occurred when the building was brightly lit during large nocturnal migration events and when winds concentrated birds along the Chicago lakeshore. We estimate that halving lighted window area decreases collision counts by 11× in spring and 6× in fall. Bird mortality could be reduced by ∼60% at this site by decreasing lighted window area to minimum levels historically recorded. Our study provides strong support for a relationship between nocturnal migration magnitude and urban bird mortality, mediated by light pollution and local atmospheric conditions. Although our research focuses on a single site, our findings have global implications for reducing or eliminating a critically important cause of bird mortality.North America has lost nearly one-third of its birdlife in the last half-century, with migratory species experiencing particularly acute declines (1). Fatal collisions with built structures represent a major source of direct, human-caused bird mortality across North America, second only to predation by domestic cats (2). Estimates indicate that between 365 million and 988 million birds die annually in collisions with buildings in the United States, with another 16 million to 42 million annual deaths in Canada (2, 3). Birds may collide with glass windows because they reflect the surrounding environment or allow birds to perceive a seemingly open pathway to the interior of the building (4). For the billions of birds that migrate at night, outdoor lighting (e.g., streetlights and floodlights) and interior lighting from buildings may be disorienting and draw birds into built-up areas, at high risk to collide with infrastructure (5–8). Light pollution not only alters nocturnal migratory behavior on a large scale (5, 7), but is also an acute conservation concern. Nocturnal collisions with well-lit communication towers alone are estimated to kill appreciable percentages of the populations of sensitive species (9).Avian collisions with lighted structures have been documented in the scientific literature as early as the 19th century (10–12). In recent decades, this link between collisions and light pollution has been the subject of detailed investigation (8, 13–16). Observers of bird–building collisions and tower kills have long remarked on the apparent influence of meteorological factors such as cloud ceiling, fog, frontal passage, and abrupt changes in conditions, all of which have been associated with large mortality events (10, 13, 17–24). Steady-burning lights may be particularly hazardous (25). Due to high building density and intensity of artificial lighting, cities are of particular concern. Reports of mass collisions at lighted buildings in urban areas are frequent in both the popular and scientific press (13, 19–21, 26).Understanding, predicting, and preventing collision mortality are areas of active scientific inquiry and priorities for policymakers (1, 13). Collisions occur more frequently during migration seasons and impact numerous species of migratory birds (29), and recent work suggests that nocturnal migratory movements can be useful for predicting bird–window collisions (30). Lights-out programs, which encourage the public to extinguish outdoor lighting to protect migratory birds, are receiving increasing attention (13). The act of extinguishing lighting allows birds to immediately return to normal, safe behavior (7) and reduces mortality at lighted buildings (13). Presently, advisories are generally issued for a given time period (e.g., peak migration periods) or on specific nights when weather conditions are favorable for large migratory movements [e.g., using migration forecasting, (31, 32)].Here, we integrate meteorological, migration-intensity, and window-radiance data to understand how these factors interact to cause bird collisions. We use a 21-y dataset of fatal collisions recorded at a single large building (McCormick Place Lakeside Center) in Chicago, IL (Fig. 1), to understand the behavioral, environmental, and anthropogenic drivers of these mortality events. Chicago poses the greatest potential risk from light pollution to migrating birds of all cities in the United States (33), and over 40,000 dead birds have been recovered from McCormick Place alone since 1978 (Figs. 2 and and3).3). Since 2000, we have recorded the number of birds and the lighting status of each window bay during dawn collision monitoring. Nocturnal lighting at McCormick Place correlates positively with bird collisions in many songbird species (34), but this association has not been quantified in the context of other important factors, including migration intensity and weather conditions. We estimate the effect of window lighting on collision counts and assess how the intensity of nocturnal bird migration mediates this relationship. We also test whether wind and weather conditions may magnify these associations. Finally, we investigate the spatiotemporal scales at which weather and migration data best explain collision mortality, identifying the times of night and areas of airspace associated with these events.Open in a separate windowFig. 1.Location of McCormick Place along the Chicago lakefront. The Lakeside Center building monitored in this study is highlighted in red in a three-dimensional rendering.Open in a separate windowFig. 2.Summary of collisions recorded at McCormick Place and regional bird migration between 2000 and 2020. (Upper) Individual years are drawn in different colors. Dates are given for mortality events totaling more than 50 birds. Pie charts show the family (fam.) composition of collected birds, with families representing less than 5% of total collisions merged into a single “other” category. (Lower) Summed annual migration passage at the KLOT radar in estimated number of individual birds (years colored). (Lower, Inset) Summed seasonal passage totals in estimated number of birds crossing a 75-km transect, with each point representing a year. Estimates are based on methods from ref. 35.Open in a separate windowFig. 3.Recorded collisions by year and window lighting. (A) Collisions recorded at McCormick Place between 1982 and 2020 for spring (light gray) and fall (dark gray) seasons. Horizontal lines with numeric labels show average seasonal collision totals before and after the window-lighting regime changed from fully lighted to partially lighted in 1999. The year 1997 is not shown because construction limited access to the site during that year. (B) Mean recorded daily collisions by window-lighting status from 2000 to 2020. 相似文献
83.
84.
Francisco J. Jeanneret Brith María J. Reyes Andreani María A. Cruz Contreras Csar M. Castillo Vega Juan E. Jeanneret Brith Juan F. Pavez Prez Manuela Badilla Rajevic 《Journal of community psychology》2021,49(1):58-76
In Latin America, one of the key tasks of Community and Liberation Psychology has been to recover the memories of marginalized and excluded communities that have experienced multiple pasts marked by political violence. In Chile, researchers have focused on poor urban neighborhoods, where the question of how memories are transmitted in areas where conflicts and violence are still present has been overlooked. In this context, the following article aims to analyze the ways in which memories are transmitted in a neighborhood that has a long organizational history in the struggle against social inequalities; while at the same time being classified as a critical area by the state due to its current levels of violence and social conflict. The researchers led a 3‐year case study from an ethnographic perspective, and applied a collaborative methodology that brought together the research team and the members of a territorial organization. The analysis is based on 72 interviews, 5 conversation groups and ethnographic observation. The data was analyzed using discourse analysis. The results revealed that the main form of memory transmission is not based on intergenerational narratives of the past, but rather on joint action; namely, dialogical practices among neighborhood residents that generate an ethos; a common way of life. 相似文献
85.
86.
Md R. Rahaman Karen A. Alroy Chris A. Van Beneden Michael S. Friedman Erin D. Kennedy Mahmudur Rahman Arunmozhi Balajee A.K.M. Muraduzzaman Tahmina Shirin Meerjady S. Flora Eduardo Azziz-Baumgartner 《Emerging infectious diseases》2021,27(1):324
In April 2017, surveillance detected a surge in severe acute respiratory infections (SARI) in Bangladesh. We collected specimens from SARI patients and asymptomatic controls for analysis with multipathogen diagnostic tests. Influenza A(H1N1)pdm09 was associated with the SARI epidemic, suggesting that introducing vaccines and empiric antiviral drugs could be beneficial. 相似文献
87.
The incidence of lung cancer is affected by air pollution, especially in high-density urban areas with heavy road traffic and dense urban form. Several studies have examined the direct relationship between lung cancer incidence and road traffic as well as urban form. However, the results are still inconsistent for high-density urban areas. This study focused on urban form and road traffic, aiming at revealing their relationship with lung cancer incidence in high-density urban areas at the neighborhood level. For this, an ecological study was conducted in downtown Shanghai to identify important indicators and explore quantitative associations. Negative binomial regression was fitted with lung cancer incidence as the dependent variable. The independent variables included indicators for road traffic and urban form, greenness, demographic, and socio-economic factors. The results showed that building coverage, averaged block perimeter area ratio, density of metro station without the glass barrier system, and the percentage of low-quality residential land were positively correlated with lung cancer incidence in the neighborhood, while population density was negatively correlated with lung cancer incidence. This study found a strong self-selection effect of socio-economic factors in the relationship between lung cancer incidence and greenness. These results may be useful for conducting health impact assessments and developing spatial planning interventions for respiratory health in high-density urban areas. 相似文献
88.
Ozone is the third most important anthropogenic greenhouse gas after carbon dioxide and methane but has a larger uncertainty in its radiative forcing, in part because of uncertainty in the source characteristics of ozone precursors, nitrogen oxides, and volatile organic carbon that directly affect ozone formation chemistry. Tropospheric ozone also negatively affects human and ecosystem health. Biomass burning (BB) and urban emissions are significant but uncertain sources of ozone precursors. Here, we report global-scale, in situ airborne measurements of ozone and precursor source tracers from the NASA Atmospheric Tomography mission. Measurements from the remote troposphere showed that tropospheric ozone is regularly enhanced above background in polluted air masses in all regions of the globe. Ozone enhancements in air with high BB and urban emission tracers (2.1 to 23.8 ppbv [parts per billion by volume]) were generally similar to those in BB-influenced air (2.2 to 21.0 ppbv) but larger than those in urban-influenced air (−7.7 to 6.9 ppbv). Ozone attributed to BB was 2 to 10 times higher than that from urban sources in the Southern Hemisphere and the tropical Atlantic and roughly equal to that from urban sources in the Northern Hemisphere and the tropical Pacific. Three independent global chemical transport models systematically underpredict the observed influence of BB on tropospheric ozone. Potential reasons include uncertainties in modeled BB injection heights and emission inventories, export efficiency of BB emissions to the free troposphere, and chemical mechanisms of ozone production in smoke. Accurately accounting for intermittent but large and widespread BB emissions is required to understand the global tropospheric ozone burden.Tropospheric ozone (O3) has been the focus of decades of scientific research due to its central role in atmospheric chemistry (1), its adverse impact on human and ecosystem health (2, 3), and its role as a climate forcer (4, 5). Despite this focus, there remains considerable uncertainty in tropospheric O3 production pathways, precursor sources, and long-term trends. Sources of tropospheric O3 include downward transport from the stratosphere and photochemical production from a complex set of coupled reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs), each of which is in turn emitted from both anthropogenic and natural sources (1, 6). The contribution of fossil fuel combustion to tropospheric O3 has recently declined in the United States and in Europe, proportionally increasing the contribution from natural sources (7–10). However, the spatial distribution of anthropogenic O3 precursor emissions have shifted to lower latitudes (11, 12), where they are still increasing (13). Additionally, globally averaged tropospheric O3 has increased over the past five decades (14, 15). Understanding the sources of tropospheric O3 is thus essential to explain this trend and to inform the development of effective mitigation strategies from regional to hemispheric scales.Biomass burning (BB) is an important source of O3 precursors (16–19). A recent study based on observed O3 to carbon monoxide (CO) enhancements in smoke plumes attributed 3.5% of the global tropospheric chemical O3 production to BB emissions (19). Other studies have accounted for the numerous production and destruction pathways of O3 in the troposphere using global chemical transport models (CTMs) to estimate the global budget of O3 (20, 21). However, few studies separately quantify the contributions of fossil fuel combustion and BB emissions to global tropospheric O3 (22). Global inventories attribute five times more NOx (23, 24) but roughly equal VOC emissions (17, 25) to fossil fuel combustion (hereafter referred to as urban sources) compared with BB. However, precursor emissions do not necessarily determine tropospheric O3 production close to the sources because of the nonlinearity of O3 formation chemistry (26, 27). Additionally, global CTMs do not always agree on the tropospheric O3 burden, suggesting possible deficiencies with emission inventories of O3 precursors and/or an incomplete representation of O3 chemistry (21, 28–30), although a recent model intercomparison study showed that the model ensemble reproduced well the salient spatial, seasonal, and decadal variability and trends of tropospheric O3 (31).Large-scale in situ observational constraints commensurate with the grid resolution of current global CTMs are rare. Instead, modeling studies often rely on ozonesonde-derived climatologies and satellite-based remote sensing observations to constrain tropospheric O3 distributions and precursor sources (20, 32, 33). The recent NASA Atmospheric Tomography (ATom) mission provides global-scale and seasonally resolved in situ measurements of O3 and CO and a comprehensive suite of trace gases and aerosol parameters, including tracers of BB and urban emissions (34). ATom sampled the remote troposphere from the Arctic to the Antarctic over the Pacific and Atlantic Oceans using repeated vertical profiles from ∼0.2 to ∼13 km in altitude during four seasonal deployments between 2016 and 2018 (Fig. 1). Recently, the ubiquitous presence of dilute BB smoke in the remote troposphere and its significant contribution to aerosol mass loading was established using ATom observations (35). Here, we use ATom measurements to quantify the individual contributions of urban and BB emissions to O3 in the remote global troposphere using tracers specific to each source. We compare this analysis with simulations from three global CTMs that alternatively set BB and urban emissions to zero to evaluate their impact on modeled tropospheric O3.Open in a separate windowFig. 1.Map of ATom flight tracks from the four seasonal global circuits colored by tropospheric O3 mixing ratios. Note that the color scale terminates at 70 ppbv of O3, and higher values are shown in red. Measurements with a strong stratospheric influence were parsed out as indicated in Materials and Methods. 相似文献
89.
Elonore Resongles Volker Dietze David C. Green Roy M. Harrison Raquel Ochoa-Gonzalez Anja H. Tremper Dominik J. Weiss 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(26)
Although leaded gasoline was banned at the end of the last century, lead (Pb) remains significantly enriched in airborne particles in large cities. The remobilization of historical Pb deposited in soils from atmospheric removal has been suggested as an important source providing evidence for the hypothetical long-term persistency of lead, and possibly other pollutants, in the urban environment. Here, we present data on Pb isotopic composition in airborne particles collected in London (2014 to 2018), which provide strong support that lead deposited via gasoline combustion still contributes significantly to the lead burden in present-day London. Lead concentration and isotopic signature of airborne particles collected at a heavily trafficked site did not vary significantly over the last decade, suggesting that sources remained unchanged. Lead isotopic composition of airborne particles matches that of road dust and topsoils and can only be explained with a significant contribution (estimate of 32 ± 10 to 43 ± 9% based on a binary mixing model) of Pb from leaded gasoline. The lead isotopes furthermore suggest significant contributions from nonexhaust traffic emissions, even though isotopic signatures of anthropogenic sources are increasingly overlapping. Lead isotopic composition of airborne particles collected at building height shows a similar signature to that collected at street level, suggesting effective mixing of lead within the urban street canyon. Our results have important implications on the persistence of Pb in urban environments and suggest that atmospheric Pb reached a baseline in London that is difficult to decrease further with present policy measures.Risk assessments of environmental lead (Pb) exposure have drawn the conclusion that it is not possible to identify a blood Pb level below which no adverse impact is detectable (1, 2). Even very low blood Pb levels in children are associated with a loss of full-scale intelligence quotient (IQ) score, and the curve steepens at lower blood Pb levels, with a greater loss of IQ points per unit of blood Pb in the lowest exposure groups (1, 2). Although currently available research has included subjects with very low blood Pb, it is not possible for such studies to go to zero Pb, but it is prudent to treat Pb as a nonthreshold toxin (3). Bellinger estimated full-scale IQ point losses in the early 2000s in the US child population associated with six medical conditions, four neurodevelopmental disorders, two socioeconomic, nutritional, and psychosocial factors, and three environmental chemical exposures (methylmercury, organophosphate pesticides, and Pb) (1). Pb exposure ranked second among all fifteen risk factors, behind only preterm birth and first among the environmental chemical exposures. Much of the summed IQ loss occurred among the lowest-exposed groups due to their larger numbers, and even if population blood Pb levels have declined since the Bellinger study and more children have hence moved into the lower exposure groups (4), the total IQ loss across the population may remain substantial.A major policy achievement in our efforts to reduce Pb in the environment has been the global phaseout of Pb from gasoline at the end of the last century, which resulted in a drastic decrease of atmospheric Pb concentration, especially in urban and remote areas of Europe and North America. While exposure to Pb from paints, Pb pipes, and Pb-containing toys are now recognized as the main cause of elevated blood Pb levels in children in nonindustrial environments, Pb remains an environmental pollutant of great concern (5), as its ongoing existence in the environment affects environmental quality in cities and is raising particular concerns regarding long-term exposure (6). A significant association between Pb concentration in particulate matter smaller than 10 µm (PM10) and the US population’s blood was recently demonstrated (7), suggesting that inhalation and/or ingestion of coarse particles might be an important pathway for human exposure to Pb. Viewed in this context, Pb in the environment remains a significant threat to public health, and it is absolutely essential to accurately identify and monitor the sources and pathways of Pb in the urban environment.While it has been suggested that Pb sources in urban environments today include local and/or distant emissions from industries, coal burning, and traffic (exhaust and nonexhaust emissions) (8–11), recent works studying Pb contamination of airborne particles in (peri-)urban environments (10, 12) have suggested that ongoing contributions of lead released into the environment by leaded gasoline combustion during the last century remain an important but underestimated source. If confirmed more widely, then abatement strategies aimed at eliminating Pb fully from the urban environment need to be adjusted. It is very important to note that these recent findings are in line with an early study of Pb in sediments and water of the San Francisco Bay, suggesting already in the early 2000s that recycling of legacy Pb from leaded gasoline may be a continuing threat to environmental health (13, 14). Furthermore, a shift in Pb concentrations within size distribution, from the fine range (PM2.5) to the coarse range (PM10), has been highlighted after the ban of leaded gasoline in the United States and Europe and ascribed to a change in dominant Pb sources consisting of industrial emissions and road dust resuspension instead of direct vehicle exhausts (15).Alkyl Pb motor fuel additives were used in the United Kingdom from the 1930s until phaseout was completed at the end of 1999. Although added in an organometallic form, Pb emissions from vehicles were predominantly in the form of a fine aerosol of inorganic Pb salts (16). The maximum permitted level of Pb in UK motor fuel was 0.84 g ⋅ L−1. The limit fell successively to 0.40 g ⋅ L−1 in 1981 and 0.15 g ⋅ L−1 in 1986. At its peak in the early 1980s, of the order of 7,000 tons per year of Pb were emitted from road traffic exhaust in the United Kingdom, which had fallen to just 30 tons by the year 2000 (17). Until its final ban, leaded gasoline combustion remained the most important source of Pb emissions in the UK atmosphere (17). In the early 1980s, annual average airborne Pb concentrations at background sites in central London were around 500 to 600 ng ⋅ m−3, which fell to around 300 ng ⋅ m−3 in the second half of the 1980s and then dropped progressively to around 20 ng ⋅ m−3 in 2000. Airborne concentrations now are generally less than 10 ng ⋅ m−3 and have remained steady over the last decade (18).Using Pb isotope composition of atmospheric particles has been a crucial tool in tracing the origin of Pb in the environment and identifying leaded gasoline as a dominant source during the 20th century (19). Following the removal of Pb additives from gasoline in Europe, Pb isotope ratios of atmospheric particles generally changed toward more radiogenic values due to the increase in the relative contribution of other Pb sources (19). Such an evolution was recorded in London airborne particles between 1998 and 2001 during the final phasing out of leaded gasoline in the United Kingdom (20). However, this trend was no longer observed a decade later, leading to the suggestion that leaded gasoline remained an important source of atmospheric Pb (9).The aim of this study was to test if remobilization of historical gasoline-derived Pb remains today an important and persistent source of Pb in London and the urban environment. To this end, we studied the Pb isotope composition of airborne particles collected in central London between 1995 and 2018 using new and historical data and quantified the possible contribution of historical gasoline Pb. London is representative of many large cities in developed countries, where particle emissions from industries and coal combustion are now relatively low, and where traffic emissions and dust resuspension represent dominant sources of airborne particles. Therefore, it constitutes an ideal site to study the persistence of Pb in urban environments almost 20 y after the complete phaseout of leaded gasoline. The variability of Pb concentration and isotopic composition was determined in PM10 and total suspended particles (TSPpassive) during 1 mo at a heavily trafficked site in central London (Marylebone Road site [MR]), where particle emissions are dominated by traffic. The data were compared with the previously published isotopic composition of potential Pb sources and PM10 from this historically monitored site. In addition, the variability of Pb isotopic composition in TSPpassive collected between 2014 and 2018 at building height in central London (Imperial College London site [IC]) is reported to determine mixing and source contributions within the urban canyon. 相似文献
90.
Abdul Azeez E P G. Anbu Selvi Garima Sharma Senthil Kumar A P 《The International journal of health planning and management》2021,36(1):83-99
The practice of allopathic medicine by informal healthcare practitioners (IHPs) is ubiquitous in India. However, a little is known about the patients' experiences and IHPs' perspectives. The core questions guided the present study were (1) why do urban poor approach IHPs for healthcare? (2) what are their experiences of availing services from IHPs? and (3) what are the perspectives of IHPs about their practice with the population they serve? A qualitative research design guided the study. The study was conducted in the Gurugram city of Haryana, India. Nine IHPs and twenty‐seven patients who fit into the pre‐established inclusion criteria were interviewed. The findings of the study underline the structural constrains of healthcare access to the poor in India and the mutual dependencies between IHPs and the urban poor. Three themes were emerged corresponding to the perspectives of IHPs, and five themes were generated, which describes patients' experiences and perspectives of availing treatment. The factors that attract and sustain patients to IHPs are a mixture of socio‐economic aspects, which include poverty, inaccessibility, unaffordability, inefficient public healthcare facilities, and the positive behavioural and treatment attributes of the practitioners. The study implies urgent policy interventions to ensure quality healthcare to urban poor. 相似文献