5,271 research outputs found

    Aeolian And Fluvial Depositional Systems Discrimination In Wireline Logs: Unayzah Formation, Central Saudi Arabia

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    The objective of tills study is to discriminate between aeolian and fluvial deposits of the Permian Unayzah formation in Central Saudi Arabia by using wireline logs. The analysis is conducted on wire-line logs (field data): Density, sonic, gamma, and neutron, from two vertical wells (U1 and U2) in Central Saudi Arabia. Core data are available at well location U1 but not at U2. We apply an automated neural-network method to the wireline data for facies discrimination. Our analysis has been applied to the logs of well U2 after training the method on U1 logs using available core information. Results indicate that the Unayzah formation at well location U2 consists mainly of fluvial deposits (about 90%), which is consistent with previous studies and is supported by surface seismic images. We also investigate an analysis method based On the Fourier transform. We study the decay of the energy spectrum in the frequency domain and estimate the associated power-law exponent (i.e., the slope of the decay) for each depositional system. Analysis on the porosity logs (density, neutron, sonic, and shear), which are highly influenced by deposition composition and texture, has shown that the exponent is about the same for fluvial deposits at both well locations, while it is different for aeolian deposits.Massachusetts Institute of Technology. Borehole Acoustics and Logging ConsortiumMassachusetts Institute of Technology. Earth Resources Laboratory. Reservoir Delineation Consortiu

    Rising rural body-mass index is the main driver of the global obesity epidemic in adults

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    Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities1,2. This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity3,4,5,6. Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017—and more than 80% in some low- and middle-income regions—was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing—and in some countries reversal—of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories

    Wellness and coping of physicians who worked in ICUs during the pandemic: A multicenter cross-sectional North American survey

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    OBJECTIVES: Few surveys have focused on physician moral distress, burnout, and professional fulfilment. We assessed physician wellness and coping during the COVID-19 pandemic. DESIGN: Cross-sectional survey using four validated instruments. SETTING: Sixty-two sites in Canada and the United States. SUBJECTS: Attending physicians (adult, pediatric; intensivist, nonintensivist) who worked in North American ICUs. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: We analysed 431 questionnaires (43.3% response rate) from 25 states and eight provinces. Respondents were predominantly male (229 [55.6%]) and in practice for 11.8 ± 9.8 years. Compared with prepandemic, respondents reported significant intrapandemic increases in days worked/mo, ICU bed occupancy, and self-reported moral distress (240 [56.9%]) and burnout (259 [63.8%]). Of the 10 top-ranked items that incited moral distress, most pertained to regulatory/organizational ( n = 6) or local/institutional ( n = 2) issues or both ( n = 2). Average moral distress (95.6 ± 66.9), professional fulfilment (6.5 ± 2.1), and burnout scores (3.6 ± 2.0) were moderate with 227 physicians (54.6%) meeting burnout criteria. A significant dose-response existed between COVID-19 patient volume and moral distress scores. Physicians who worked more days/mo and more scheduled in-house nightshifts, especially combined with more unscheduled in-house nightshifts, experienced significantly more moral distress. One in five physicians used at least one maladaptive coping strategy. We identified four coping profiles (active/social, avoidant, mixed/ambivalent, infrequent) that were associated with significant differences across all wellness measures. CONCLUSIONS: Despite moderate intrapandemic moral distress and burnout, physicians experienced moderate professional fulfilment. However, one in five physicians used at least one maladaptive coping strategy. We highlight potentially modifiable factors at individual, institutional, and regulatory levels to enhance physician wellness

    141: Similar Risks for Hypothyroidism in Myeloablative and Reduced-Intensity Allogeneic Hematopoietic Cell Transplant Survivors

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    Similar Risks for Chronic Kidney Disease in Long-Term Survivors of Myeloablative and Reduced-Intensity Allogeneic Hematopoietic Cell Transplantation

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    AbstractChronic kidney disease (CKD) in recipients of myeloablative (MA) allogeneic hematopoietic cell transplantation (HCT) has been well characterized. However, the risk of CKD after HCT using reduced-intensity conditioning (RIC) is not well known. We compared the incidence of CKD by conditioning regimen in 221 allogeneic HCT recipients (MA = 117, RIC = 104) who had survived for ≄1 year post-HCT and had no history of CKD pretransplant. CKD was defined as glomerular filtration rate (GFR) <60 mL/min/1.73 m2 for ≄3 months anytime after 180 days post-HCT. The median follow-up was 28 months (range: 12-75) for MA and 25 months (range: 12-67) for the RIC group. The 3-year cumulative incidence rate of CKD was 28% (95% confidence intervals [CI], 19%-36%) in MA and 29% (95% CI, 20%-38%) in the RIC group (P = .44). In multivariate analysis, conditioning regimen intensity had no impact on the risk of developing CKD (relative risk [RR] for MA 1.50 [95% CI, 0.78-2.89] versus the RIC regimen). Factors independently associated with an increased risk of CKD were older age at transplant, acute graft-versus-host disease, cyclosporine use for >6 months, and acute kidney injury in the early posttransplant period. CKD is frequent in long-term adult allogeneic HCT survivors, but RIC is associated with similar risks as MA conditioning. Continuous monitoring of renal function is necessary in allogeneic HCT survivors, and studies exploring prevention strategies are needed

    Global patterns of mortality in international migrants: a systematic review and meta-analysis.

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    BACKGROUND: 258 million people reside outside their country of birth; however, to date no global systematic reviews or meta-analyses of mortality data for these international migrants have been done. We aimed to review and synthesise available mortality data on international migrants. METHODS: In this systematic review and meta-analysis, we searched MEDLINE, Embase, the Cochrane Library, and Google Scholar databases for observational studies, systematic reviews, and randomised controlled trials published between Jan 1, 2001, and March 31, 2017, without language restrictions. We included studies reporting mortality outcomes for international migrants of any age residing outside their country of birth. Studies that recruited participants exclusively from intensive care or high dependency hospital units, with an existing health condition or status, or a particular health exposure were excluded. We also excluded studies limited to maternal or perinatal outcomes. We screened studies using systematic review software and extracted data from published reports. The main outcomes were all-cause and International Classification of Diseases, tenth revision (ICD-10) cause-specific standardised mortality ratios (SMRs) and absolute mortality rates. We calculated summary estimates using random-effects models. This study is registered with PROSPERO, number CRD42017073608. FINDINGS: Of the 12 480 articles identified by our search, 96 studies were eligible for inclusion. The studies were geographically diverse and included data from all global regions and for 92 countries. 5464 mortality estimates for more than 15·2 million migrants were included, of which 5327 (97%) were from high-income countries, 115 (2%) were from middle-income countries, and 22 (<1%) were from low-income countries. Few studies included mortality estimates for refugees (110 estimates), asylum seekers (144 estimates), or labour migrants (six estimates). The summary estimate of all-cause SMR for international migrants was lower than one when compared with the general population in destination countries (0·70 [95% CI 0·65-0·76]; I2=99·8%). All-cause SMR was lower in both male migrants (0·72 [0·63-0·81]; I2=99·8%) and female migrants (0·75 [0·67-0·84]; I2=99·8%) compared with the general population. A mortality advantage was evident for refugees (SMR 0·50 [0·46-0·54]; I2=89·8%), but not for asylum seekers (1·05 [0·89-1·24]; I2=54·4%), although limited data was available on these groups. SMRs for all causes of death were lower in migrants compared with the general populations in the destination country across all 13 ICD-10 categories analysed, with the exception of infectious diseases and external causes. Heterogeneity was high across the majority of analyses. Point estimates of all-cause age-standardised mortality in migrants ranged from 420 to 874 per 100 000 population. INTERPRETATION: Our study showed that international migrants have a mortality advantage compared with general populations, and that this advantage persisted across the majority of ICD-10 disease categories. The mortality advantage identified will be representative of international migrants in high-income countries who are studying, working, or have joined family members in these countries. However, our results might not reflect the health outcomes of more marginalised groups in low-income and middle-income countries because little data were available for these groups, highlighting an important gap in existing research. Our results present an opportunity to reframe the public discourse on international migration and health in high-income countries. FUNDING: Wellcome Trust, National Institute for Health Research, Medical Research Council, Alliance for Health Policy and Systems Research, Department for International Development, Fogarty International Center, Grand Challenges Canada, International Development Research Centre Canada, Inter-American Institute for Global Change Research, National Cancer Institute, National Heart, Lung and Blood Institute, National Institute of Mental Health, Swiss National Science Foundation, World Diabetes Foundation, UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, and European Society for Clinical Microbiology and Infectious Diseases (ESCMID) Study Group Research Funding for the ESCMID Study Group for Infections in Travellers and Migrants

    Membrane-Spanning DNA Nanopores with Cytotoxic Effect.

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    DNA-based cytotoxic agents: Nanopores composed of folded DNA featuring a hydrophobic belt of ethyl phosphorothioate groups insert into bilayer membranes and kill cancer cells. The mode by which the pores achieve cell killing is elucidated with confocal microscopy

    A contribution to the deterministic modelling of circadian rhythms in cell proliferation activity

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    This paper presents a deterministic continuous model of proliferative cell activity. The classical series of connected compartments is revisited along with a simple mathematical treatment of two hypotheses: constant transit times and harmonic Ts. Several examples are presented to support these ideas, both taken from previous literature and recent experiences with the fish Carassius auratus, developed at the Junta de EnergĂ­a Nuclear, Madrid, Spain

    Emotions in context: examining pervasive affective sensing systems, applications, and analyses

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    Pervasive sensing has opened up new opportunities for measuring our feelings and understanding our behavior by monitoring our affective states while mobile. This review paper surveys pervasive affect sensing by examining and considering three major elements of affective pervasive systems, namely; “sensing”, “analysis”, and “application”. Sensing investigates the different sensing modalities that are used in existing real-time affective applications, Analysis explores different approaches to emotion recognition and visualization based on different types of collected data, and Application investigates different leading areas of affective applications. For each of the three aspects, the paper includes an extensive survey of the literature and finally outlines some of challenges and future research opportunities of affective sensing in the context of pervasive computing

    Modelling diverse root density dynamics and deep nitrogen uptake — a simple approach

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    We present a 2-D model for simulation of root density and plant nitrogen (N) uptake for crops grown in agricultural systems, based on a modification of the root density equation originally proposed by Gerwitz and Page in J Appl Ecol 11:773–781, (1974). A root system form parameter was introduced to describe the distribution of root length vertically and horizontally in the soil profile. The form parameter can vary from 0 where root density is evenly distributed through the soil profile, to 8 where practically all roots are found near the surface. The root model has other components describing root features, such as specific root length and plant N uptake kinetics. The same approach is used to distribute root length horizontally, allowing simulation of root growth and plant N uptake in row crops. The rooting depth penetration rate and depth distribution of root density were found to be the most important parameters controlling crop N uptake from deeper soil layers. The validity of the root distribution model was tested with field data for white cabbage, red beet, and leek. The model was able to simulate very different root distributions, but it was not able to simulate increasing root density with depth as seen in the experimental results for white cabbage. The model was able to simulate N depletion in different soil layers in two field studies. One included vegetable crops with very different rooting depths and the other compared effects of spring wheat and winter wheat. In both experiments variation in spring soil N availability and depth distribution was varied by the use of cover crops. This shows the model sensitivity to the form parameter value and the ability of the model to reproduce N depletion in soil layers. This work shows that the relatively simple root model developed, driven by degree days and simulated crop growth, can be used to simulate crop soil N uptake and depletion appropriately in low N input crop production systems, with a requirement of few measured parameters
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