Salinity change induces distinct climate feedbacks of nitrogen removal in saline lakes.

Current estimations of nitrogen biogeochemical cycling and N2O emissions in global lakes as well as predictions of their future changes are overrepresented by freshwater datasets, while less consideration is given to widespread saline lakes with different salinity (representing salinization or desalinization). Here, we show that N2O production by denitrification is the main process of reactive nitrogen (Nr, the general abbreviations of NH4+-N, NO2--N and NO3--N) removal in hypersaline lake sediments (e.g. Lake Chaka). The integration of our field measurements and literature data shows that in response to natural salinity decrease, potential Nr removal increases while N2O production decreases. Furthermore, denitrification-induced N2 production exhibits higher salinity sensitivity than denitrification-induced N2O production, suggesting that the contribution of N2O to Nr removal decreases with decreasing salinity. This field-investigation-based salinity response model of Nr removal indicates that under global climate change, saline lakes in the process of salinization or desalination may have distinct Nr removal and climate feedback effects: salinized lakes tend to generate a positive climate feedback, while desalinated lakes show a negative feedback. Therefore, salinity change should be considered as an important factor in assessing future trend of N2O emissions from lakes under climate change.

Simulation-based estimates and projections of global, regional and country-level maternal mortality by cause, 1990-2050.

Maternal mortality is a major global health challenge. Although progress has been made globally in reducing maternal deaths, measurement remains challenging given the many causes and frequent underreporting of maternal deaths. We developed the Global Maternal Health microsimulation model for women in 200 countries and territories, accounting for individual fertility preferences and clinical histories. Demographic, epidemiologic, clinical and health system data were synthesized from multiple sources, including the medical literature, Civil Registration Vital Statistics systems and Demographic and Health Survey data. We calibrated the model to empirical data from 1990 to 2015 and assessed the predictive accuracy of our model using indicators from 2016 to 2020. We projected maternal health indicators from 1990 to 2050 for each country and estimate that between 1990 and 2020 annual global maternal deaths declined by over 40% from 587,500 (95% uncertainty intervals (UI) 520,600-714,000) to 337,600 (95% UI 307,900-364,100), and are projected to decrease to 327,400 (95% UI 287,800-360,700) in 2030 and 320,200 (95% UI 267,100-374,600) in 2050. The global maternal mortality ratio is projected to decline to 167 (95% UI 142-188) in 2030, with 58 countries above 140, suggesting that on current trends, maternal mortality Sustainable Development Goal targets are unlikely to be met. Building on the development of our structural model, future research can identify context-specific policy interventions that could allow countries to accelerate reductions in maternal deaths.

A simulation-based comparative effectiveness analysis of policies to improve global maternal health outcomes.

The Sustainable Development Goals include a target to reduce the global maternal mortality ratio (MMR) to less than 70 maternal deaths per 100,000 live births by 2030, with no individual country exceeding 140. However, on current trends the goals are unlikely to be met. We used the empirically calibrated Global Maternal Health microsimulation model, which simulates individual women in 200 countries and territories to evaluate the impact of different interventions and strategies from 2022 to 2030. Although individual interventions yielded fairly small reductions in maternal mortality, integrated strategies were more effective. A strategy to simultaneously increase facility births, improve the availability of clinical services and quality of care at facilities, and improve linkages to care would yield a projected global MMR of 72 (95% uncertainty interval (UI) = 58-87) in 2030. A comprehensive strategy adding family planning and community-based interventions would have an even larger impact, with a projected MMR of 58 (95% UI = 46-70). Although integrated strategies consisting of multiple interventions will probably be needed to achieve substantial reductions in maternal mortality, the relative priority of different interventions varies by setting. Our regional and country-level estimates can help guide priority setting in specific contexts to accelerate improvements in maternal health.

Putative Nickel-Dependent Anaerobic Carbon Monoxide Uptake Occurs Commonly in Soils and Sediments at Ambient Temperature and Might Contribute to Atmospheric and Sub-Atmospheric Carbon Monoxide Uptake During Anoxic Conditions.

Carbon monoxide (CO) occurs naturally in the atmosphere where it plays a critical role in tropospheric chemistry. Atmospheric CO uptake by soils has been well documented as an important CO sink and has been attributed to a group of aerobic bacteria that possess a molybdenum-dependent CO dehydrogenase (Mo-CODH). CO can also be oxidized by obligate Ni-dependent anaerobes (Ni-COX) that possess nickel-dependent CODHs (Ni-CODH) but relatively little is known about their ecology or their potential to contribute to CO dynamics within soils and sediments or to soil-atmosphere CO exchanges. Results from a series of assays undertaken with diverse soils and sediments and CO concentrations of 10 ppm and 25% with incubation temperatures of 10, 25, and 60°C revealed anaerobic uptake rates with 10 ppm CO that were comparable to those measured under oxic conditions; further, anaerobic CO uptake occurred without a lag and at atmospheric and sub-atmospheric CO concentrations. Assays with 25% CO revealed previously undocumented activity at 10°C and showed extensive activity at 25°C. Results from prior studies with isolates and soils suggest that anaerobic uptake at both 10 ppm and 25% CO concentrations might be attributed to Ni-COX. Collectively the results considerably expand the ecological range for Ni-COX and indicate that they could play previously unsuspected roles in soil CO dynamics.

Short-Term Exposure to Thermophilic Temperatures Facilitates CO Uptake by Thermophiles Maintained under Predominantly Mesophilic Conditions.

Three phylogenetically and phenotypically distinct CO-oxidizing thermophiles (Alicyclobacillus macrosporangiidus CPP55 (Firmicutes), Meiothermus ruber PS4 (Deinococcus-Thermus) and Thermogemmatispora carboxidovorans PM5T (Chloroflexi)) and one CO-oxidizing mesophile (Paraburkholderia paradisi WAT (Betaproteobacteria)) isolated from volcanic soils were used to assess growth responses and CO uptake rates during incubations with constant temperatures (25 °C and 55 °C) and during multi-day incubations with a temperature regime that cycled between 20 °C and 55 °C on a diurnal basis (alternating mesophilic and thermophilic temperatures, AMTT). The results were used to test a conjecture that some thermophiles can survive in mesothermal habitats that experience occasional thermophilic temperatures. Meiothermus ruber PS4, which does not form spores, was able to grow and oxidize CO under all conditions, while the spore-forming Alicyclobacillus macrosporangiidus CPP55 grew and oxidized CO during the AMTT regime and at 55 °C, but was not active at 25 °C. Thermogemmatispora carboxidovorans PM5T, also a spore former, only grew at 55 °C but oxidized CO during AMTT and 55 °C incubations. In contrast, the non-sporing mesophile, Paraburkholderia paradisi WAT, was only able to grow and oxidize CO at 25 °C; growth and CO uptake ceased during the AMTT incubations after exposure to the initial round of thermophilic temperatures. Collectively, these results suggest that temporary, periodic exposure to permissive growth temperatures could help maintain populations of thermophiles in mesothermal habitats after deposition from the atmosphere or other sources.

Distribution and diversity of anaerobic thermophiles and putative anaerobic nickel-dependent carbon monoxide-oxidizing thermophiles in mesothermal soils and sediments.

Even though thermophiles are best known from geothermal and other heated systems, numerous studies have demonstrated that they occur ubiquitously in mesothermal and permanently cold soils and sediments. Cultivation based studies of the latter have revealed that the thermophiles within them are mostly spore-forming members of the Firmicutes. Since the geographic distribution of spores is presumably unconstrained by transport through the atmosphere, similar communities (composition and diversity) of thermophiles might be expected to emerge in mesothermal habitats after they are heated. Alternatively, thermophiles might experience environmental selection before or after heating leading to divergent communities. After demonstrating the ubiquity of anaerobic thermophiles and CO uptake in a variety of mesothermal habitats and two hot springs, we used high throughput sequencing of 16S rRNA genes to assess the composition and diversity of populations that emerged after incubation at 60°C with or without headspace CO concentrations of 25%. Anaerobic Firmicutes dominated relative abundances at most sites but anaerobic thermophilic members of the Acidobacteria and Proteobacteria were also common. Nonetheless, compositions at the amplicon sequence variant (ASV) level varied among the sites with no convergence resulting from heating or CO addition as indicated by beta diversity analyses. The distinctions among thermophilic communities paralleled patterns observed for unheated "time zero" mesothermal soils and sediments. Occupancy analyses showed that the number of ASVs occupying each of n sites decreased unimodally with increasing n; no ASV occupied all 14 sites and only one each occupied 11 and 12 sites, while 69.3% of 1873 ASVs occupied just one site. Nonetheless, considerations of distances among the sites occupied by individual ASVs along with details of their distributions indicated that taxa were not dispersal limited but rather were constrained by environmental selection. This conclusion was supported by ßMNTD and ßNTI analyses, which showed dispersal limitation was only a minor contributor to taxon distributions.

Trends in Internet Safety Education by Healthcare Providers.

INTRODUCTION: The purpose of this study was to explore healthcare provider training, comfort, and provision of internet safety counseling. Prior research has demonstrated increased parental concern regarding the pervasive access to the internet by children, including the potential impacts of risky internet behavior and adverse media exposure. METHODS: A self-reported survey was provided to a convenience sample of 31 healthcare providers during a mental health training seminar. Responses were analyzed using descriptive statistics. RESULTS: Internet safety counseling, especially regarding risky online behavior, was not a focal point of provider-patient interaction in the sample population. This finding was reinforced with more than half of the respondents indicating that they infrequently or never provide internet safety counseling (n = 17, 56%). While research has placed an emphasis on the importance of discussing the risks of exposure to violence, drugs, and sexually explicit media online, this study found that the topics most often discussed were setting time limits (77%), limiting access to media devices (67%), and supervising internet use (50%). This may be due in part to the fact that most respondents (n = 17, 57%) reported never receiving training on internet safety counseling. CONCLUSIONS: Overall, significant deficits were identified in internet safety counseling training for professionals and provision of education for families. These finding were inconsistent with the American Academy of Pediatrics recommendations around media use counseling and a point of urgent concern given the increasing time spent on media devices, particularly during the COVID pandemic.

Smoking and obesity among long-haul truck drivers in France.

INTRODUCTION: This study examines the health status of long-haul truck drivers (LHTDs) and more specifically smoking and obesity, in France. METHODS: A total of 373 French and other LHTDs were randomly interviewed at six highway rest stops. Variables recorded were self-reported sociodemographic characteristics (age, gender, marital status, and nationality), behavioral variables (consumption of sodas, daily exercise, smoking status), weight and height. Body mass index (BMI) was also calculated. Statistical analysis was conducted using chi-squared analysis and multiple logistic ordinal regression models (MLR) were developed. RESULTS: The mean age was 43.4 and the largest proportion (41.2%) of respondents were aged 40-50 years. Most respondents were French (70.3%), married (73.8%) and did not report having an active exercise routine (66.0%). Almost two-thirds of the drivers consumed daily 1-2 sodas (34.2%) or 3-4 sodas (33.2%). Based on the BMI, respondents were divided into normal (34.3%), overweight (39.8%), obese (19.5%) or morbidly obese (9.4%) categories. The mean BMI was 27.9 kg/m2 and 51.1% of LHTDs were current or active smokers. MLR analysis revealed that French LHTDs were more likely (OR=3.04; 95% CI: 1.62-5.69) to have a normal BMI compared to other drivers. Smokers were significantly more likely than non-smokers (OR=2.12; 95% CI: 1.26-3.58) to have an above normal BMI. CONCLUSIONS: These results confirm that French and other LHTDs are at high risk of non-communicable diseases. They also highlight the need to address the health risks associated with smoking and obesity among LHTDs using multifaceted strategies.

Precision mapping child undernutrition for nearly 600,000 inhabited census villages in India.

There are emerging opportunities to assess health indicators at truly small areas with increasing availability of data geocoded to micro geographic units and advanced modeling techniques. The utility of such fine-grained data can be fully leveraged if linked to local governance units that are accountable for implementation of programs and interventions. We used data from the 2011 Indian Census for village-level demographic and amenities features and the 2016 Indian Demographic and Health Survey in a bias-corrected semisupervised regression framework to predict child anthropometric failures for all villages in India. Of the total geographic variation in predicted child anthropometric failure estimates, 54.2 to 72.3% were attributed to the village level followed by 20.6 to 39.5% to the state level. The mean predicted stunting was 37.9% (SD: 10.1%; IQR: 31.2 to 44.7%), and substantial variation was found across villages ranging from less than 5% for 691 villages to over 70% in 453 villages. Estimates at the village level can potentially shift the paradigm of policy discussion in India by enabling more informed prioritization and precise targeting. The proposed methodology can be adapted and applied to diverse population health indicators, and in other contexts, to reveal spatial heterogeneity at a finer geographic scale and identify local areas with the greatest needs and with direct implications for actions to take place.

Survey data and human computation for improved flu tracking.

While digital trace data from sources like search engines hold enormous potential for tracking and understanding human behavior, these streams of data lack information about the actual experiences of those individuals generating the data. Moreover, most current methods ignore or under-utilize human processing capabilities that allow humans to solve problems not yet solvable by computers (human computation). We demonstrate how behavioral research, linking digital and real-world behavior, along with human computation, can be utilized to improve the performance of studies using digital data streams. This study looks at the use of search data to track prevalence of Influenza-Like Illness (ILI). We build a behavioral model of flu search based on survey data linked to users' online browsing data. We then utilize human computation for classifying search strings. Leveraging these resources, we construct a tracking model of ILI prevalence that outperforms strong historical benchmarks using only a limited stream of search data and lends itself to tracking ILI in smaller geographic units. While this paper only addresses searches related to ILI, the method we describe has potential for tracking a broad set of phenomena in near real-time.

Anaerobic Carbon Monoxide Uptake by Microbial Communities in Volcanic Deposits at Different Stages of Successional Development on O-yama Volcano, Miyake-jima, Japan.

Research on Kilauea and O-yama Volcanoes has shown that microbial communities and their activities undergo major shifts in response to plant colonization and that molybdenum-dependent CO oxidizers (Mo-COX) and their activities vary with vegetation and deposit age. Results reported here reveal that anaerobic CO oxidation attributed to nickel-dependent CO oxidizers (Ni-COX) also occurs in volcanic deposits that encompass different developmental stages. Ni-COX at three distinct sites responded rapidly to anoxia and oxidized CO from initial concentrations of about 10 ppm to sub-atmospheric levels. CO was also actively consumed at initial 25% concentrations and 25 °C, and during incubations at 60 °C; however, uptake under the latter conditions was largely confined to an 800-year-old forested site. Analyses of microbial communities based on 16S rRNA gene sequences in treatments with and without 25% CO incubated at 25 °C or 60 °C revealed distinct responses to temperature and CO among the sites and evidence for enrichment of known and potentially novel Ni-COX. The results collectively show that CO uptake by volcanic deposits occurs under a wide range of conditions; that CO oxidizers in volcanic deposits may be more diverse than previously imagined; and that Ni-dependent CO oxidizers might play previously unsuspected roles in microbial succession.

Reconstructing Genomes of Carbon Monoxide Oxidisers in Volcanic Deposits Including Members of the Class Ktedonobacteria.

Microorganisms can potentially colonise volcanic rocks using the chemical energy in reduced gases such as methane, hydrogen (H2) and carbon monoxide (CO). In this study, we analysed soil metagenomes from Chilean volcanic soils, representing three different successional stages with ages of 380, 269 and 63 years, respectively. A total of 19 metagenome-assembled genomes (MAGs) were retrieved from all stages with a higher number observed in the youngest soil (1640: 2 MAGs, 1751: 1 MAG, 1957: 16 MAGs). Genomic similarity indices showed that several MAGs had amino-acid identity (AAI) values >50% to the phyla Actinobacteria, Acidobacteria, Gemmatimonadetes, Proteobacteria and Chloroflexi. Three MAGs from the youngest site (1957) belonged to the class Ktedonobacteria (Chloroflexi). Complete cellular functions of all the MAGs were characterised, including carbon fixation, terpenoid backbone biosynthesis, formate oxidation and CO oxidation. All 19 environmental genomes contained at least one gene encoding a putative carbon monoxide dehydrogenase (CODH). Three MAGs had form I coxL operon (encoding the large subunit CO-dehydrogenase). One of these MAGs (MAG-1957-2.1, Ktedonobacterales) was highly abundant in the youngest soil. MAG-1957-2.1 also contained genes encoding a [NiFe]-hydrogenase and hyp genes encoding accessory enzymes and proteins. Little is known about the Ktedonobacterales through cultivated isolates, but some species can utilise H2 and CO for growth. Our results strongly suggest that the remote volcanic sites in Chile represent a natural habitat for Ktedonobacteria and they may use reduced gases for growth.

Population-scale longitudinal mapping of COVID-19 symptoms, behaviour and testing.

Despite the widespread implementation of public health measures, coronavirus disease 2019 (COVID-19) continues to spread in the United States. To facilitate an agile response to the pandemic, we developed How We Feel, a web and mobile application that collects longitudinal self-reported survey responses on health, behaviour and demographics. Here, we report results from over 500,000 users in the United States from 2 April 2020 to 12 May 2020. We show that self-reported surveys can be used to build predictive models to identify likely COVID-19-positive individuals. We find evidence among our users for asymptomatic or presymptomatic presentation; show a variety of exposure, occupational and demographic risk factors for COVID-19 beyond symptoms; reveal factors for which users have been SARS-CoV-2 PCR tested; and highlight the temporal dynamics of symptoms and self-isolation behaviour. These results highlight the utility of collecting a diverse set of symptomatic, demographic, exposure and behavioural self-reported data to fight the COVID-19 pandemic.

Population-scale Longitudinal Mapping of COVID-19 Symptoms, Behavior, and Testing Identifies Contributors to Continued Disease Spread in the United States.

Despite social distancing and shelter-in-place policies, COVID-19 continues to spread in the United States. A lack of timely information about factors influencing COVID-19 spread and testing has hampered agile responses to the pandemic. We developed How We Feel, an extensible web and mobile application that aggregates self-reported survey responses, to fill gaps in the collection of COVID-19-related data. How We Feel collects longitudinal and geographically localized information on users' health, behavior, and demographics. Here we report results from over 500,000 users in the United States from April 2, 2020 to May 12, 2020. We show that self- reported surveys can be used to build predictive models of COVID-19 test results, which may aid in identification of likely COVID-19 positive individuals. We find evidence among our users for asymptomatic or presymptomatic presentation, as well as for household and community exposure, occupation, and demographics being strong risk factors for COVID-19. We further reveal factors for which users have been SARS-CoV-2 PCR tested, as well as the temporal dynamics of self- reported symptoms and self-isolation behavior in positive and negative users. These results highlight the utility of collecting a diverse set of symptomatic, demographic, and behavioral self- reported data to fight the COVID-19 pandemic.

Publisher Correction: Building an international consortium for tracking coronavirus health status.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Ecological and Genomic Attributes of Novel Bacterial Taxa That Thrive in Subsurface Soil Horizons.

While most bacterial and archaeal taxa living in surface soils remain undescribed, this problem is exacerbated in deeper soils, owing to the unique oligotrophic conditions found in the subsurface. Additionally, previous studies of soil microbiomes have focused almost exclusively on surface soils, even though the microbes living in deeper soils also play critical roles in a wide range of biogeochemical processes. We examined soils collected from 20 distinct profiles across the United States to characterize the bacterial and archaeal communities that live in subsurface soils and to determine whether there are consistent changes in soil microbial communities with depth across a wide range of soil and environmental conditions. We found that bacterial and archaeal diversity generally decreased with depth, as did the degree of similarity of microbial communities to those found in surface horizons. We observed five phyla that consistently increased in relative abundance with depth across our soil profiles: Chloroflexi, Nitrospirae, Euryarchaeota, and candidate phyla GAL15 and Dormibacteraeota (formerly AD3). Leveraging the unusually high abundance of Dormibacteraeota at depth, we assembled genomes representative of this candidate phylum and identified traits that are likely to be beneficial in low-nutrient environments, including the synthesis and storage of carbohydrates, the potential to use carbon monoxide (CO) as a supplemental energy source, and the ability to form spores. Together these attributes likely allow members of the candidate phylum Dormibacteraeota to flourish in deeper soils and provide insight into the survival and growth strategies employed by the microbes that thrive in oligotrophic soil environments.IMPORTANCE Soil profiles are rarely homogeneous. Resource availability and microbial abundances typically decrease with soil depth, but microbes found in deeper horizons are still important components of terrestrial ecosystems. By studying 20 soil profiles across the United States, we documented consistent changes in soil bacterial and archaeal communities with depth. Deeper soils harbored communities distinct from those of the more commonly studied surface horizons. Most notably, we found that the candidate phylum Dormibacteraeota (formerly AD3) was often dominant in subsurface soils, and we used genomes from uncultivated members of this group to identify why these taxa are able to thrive in such resource-limited environments. Simply digging deeper into soil can reveal a surprising number of novel microbes with unique adaptations to oligotrophic subsurface conditions.

Atmospheric carbon monoxide oxidation is a widespread mechanism supporting microbial survival.

Carbon monoxide (CO) is a ubiquitous atmospheric trace gas produced by natural and anthropogenic sources. Some aerobic bacteria can oxidize atmospheric CO and, collectively, they account for the net loss of ~250 teragrams of CO from the atmosphere each year. However, the physiological role, genetic basis, and ecological distribution of this process remain incompletely resolved. In this work, we addressed these knowledge gaps through culture-based and culture-independent work. We confirmed through shotgun proteomic and transcriptional analysis that the genetically tractable aerobic soil actinobacterium Mycobacterium smegmatis upregulates expression of a form I molydenum-copper carbon monoxide dehydrogenase by 50-fold when exhausted for organic carbon substrates. Whole-cell biochemical assays in wild-type and mutant backgrounds confirmed that this organism aerobically respires CO, including at sub-atmospheric concentrations, using the enzyme. Contrary to current paradigms on CO oxidation, the enzyme did not support chemolithoautotrophic growth and was dispensable for CO detoxification. However, it significantly enhanced long-term survival, suggesting that atmospheric CO serves a supplemental energy source during organic carbon starvation. Phylogenetic analysis indicated that atmospheric CO oxidation is widespread and an ancestral trait of CO dehydrogenases. Homologous enzymes are encoded by 685 sequenced species of bacteria and archaea, including from seven dominant soil phyla, and we confirmed genes encoding this enzyme are abundant and expressed in terrestrial and marine environments. On this basis, we propose a new survival-centric model for the evolution of aerobic CO oxidation and conclude that, like atmospheric H2, atmospheric CO is a major energy source supporting persistence of aerobic heterotrophic bacteria in deprived or changeable environments.

Developing national strategies for reaching men with HIV testing services in Tanzania: results from the male catch-up plan.

BACKGROUND: According to the 2016-2017 Tanzania HIV Impact Survey, 55% of men diagnosed with HIV during the survey self-reported that they were unaware of their HIV status. As a response, the Government of Tanzania launched a Test and Treat campaign in June 2018 with a focus on reaching men and developed the 2018-2020 Male Catch-Up plan. This article reports (1) the enablers and barriers of HIV testing services (HTS) uptake among men (2) and describes the strategies that were proposed as part of the Male Catch-Up Plan to address some of these barriers. METHOD: Qualitative in-depth interviews were conducted with 23 men in Dar es Salaam to explore HTS enablers and barriers. To develop the Male Catch-Up Plan strategies, a desk review of published studies, and analyses of national implementers of HIV/AIDS interventions were conducted. An additional 123 interviews were also carried out with key implementers of HIV/AIDS interventions, healthcare workers, secondary school boys and members of the community in Iringa and Tanga. RESULTS: Enablers of HTS included the desire to check one's health, high HIV risk perception, wanting to protect oneself if tested negative, and being encouraged by their sexual partners. Barriers of HTS were fear of a positive test result, and low HIV risk perception. Proposed strategies from the Male Catch-Up Plan to address these barriers included non-biomedical and biomedical approaches. Non-biomedical strategies are social and cultural approaches to promote an enabling environment to encourage health seeking behavior, safe behavior, and providing peer education programs and social marketing to promote condoms. Biomedical approaches consisted of expanding targeted HIV testing, HIV self-testing, and integrating HIV services with other health services. CONCLUSION: A number of barriers contribute to the low uptake of HTS among men in Tanzania. National strategies have been developed to address these HTS barriers and guide the national Test and Treat campaign focusing on increasing HTS uptake among men.