2,582 research outputs found
Atmospheric observation-based global SF6 emissions - comparison of top-down and bottom-up estimates
Emissions of sulphur hexafluoride (SF6), one of the strongest greenhouse gases on a per molecule basis, are targeted to be collectively reduced under the Kyoto Protocol. Because of its long atmospheric lifetime (≈3000 years), the accumulation of SF6 in the atmosphere is a direct measure of its global emissions. Examination of our extended data set of globally distributed high-precision SF6 observations shows an increase in SF6 abundance from near zero in the 1970s to a global mean of 6.7 ppt by the end of 2008. In-depth evaluation of our long-term data records shows that the global source of SF6 decreased after 1995, most likely due to SF6 emission reductions in industrialised countries, but increased again after 1998. By subtracting those emissions reported by Annex I countries to the United Nations Framework Convention of Climatic Change (UNFCCC) from our observation-inferred SF6 source leaves a surprisingly large gap of more than 70–80% of non-reported SF6 emissions in the last decade
Accessing the SEED Genome Databases via Web Services API: Tools for Programmers
<p>Abstract</p> <p>Background</p> <p>The SEED integrates many publicly available genome sequences into a single resource. The database contains accurate and up-to-date annotations based on the subsystems concept that leverages clustering between genomes and other clues to accurately and efficiently annotate microbial genomes. The backend is used as the foundation for many genome annotation tools, such as the Rapid Annotation using Subsystems Technology (RAST) server for whole genome annotation, the metagenomics RAST server for random community genome annotations, and the annotation clearinghouse for exchanging annotations from different resources. In addition to a web user interface, the SEED also provides Web services based API for programmatic access to the data in the SEED, allowing the development of third-party tools and mash-ups.</p> <p>Results</p> <p>The currently exposed Web services encompass over forty different methods for accessing data related to microbial genome annotations. The Web services provide comprehensive access to the database back end, allowing any programmer access to the most consistent and accurate genome annotations available. The Web services are deployed using a platform independent service-oriented approach that allows the user to choose the most suitable programming platform for their application. Example code demonstrate that Web services can be used to access the SEED using common bioinformatics programming languages such as Perl, Python, and Java.</p> <p>Conclusions</p> <p>We present a novel approach to access the SEED database. Using Web services, a robust API for access to genomics data is provided, without requiring large volume downloads all at once. The API ensures timely access to the most current datasets available, including the new genomes as soon as they come online.</p
Synthesis and structure - Activity relationship study of potent cytotoxic analogues of the marine alkaloid Lamellarin D
The marine alkaloid, Lamellarin D (Lam-D), has shown potent cytotoxicity in numerous cancer cell lines, and was recently identified as a potent topoisomerase I inhibitor. A library of open lactone analogs of Lam-D was prepared from a methyl 5,6-dihydropyrrolo[2,1-a]isoquinoline-3- carboxylate scaffold (1) by introducing various aryl groups through sequential and regioselective bromination, followed by Pd(0)-catalyzed Suzuki cross-coupling chemistry. The compounds were obtained in a 24-44% overall yield, and tested in a panel of three human tumor cell lines, MDA-MB- 231 (breast), A-549 (lung), and HT-29 (colon), to evaluate their cytotoxic potential. From these data the SAR study concluded that more than 75% of the open-chain Lam-D analogs tested showed cytotoxicity in a low micromolar GI50 range
Exploring providers’ perspectives of a community based TB approach in Southern Ethiopia: implication for community based approaches
Abstract
Background
There is increasing interest in the role of close-to-community providers in supporting universal health coverage, but questions remain about the best approaches to supporting and motivating these providers, and the optimal package they can deliver indifferent contexts and support required. We report on the experiences of different health providers involved in a community based intervention to support access to tuberculosis diagnosis and treatment in Southern Ethiopia.
Methods
The aim of the study is to explore the experiences of health providers in delivering a community-based tuberculosis package in southern Ethiopia and to draw lessons for community-based programmes. A qualitative methodology was used. Methods included in-depth interviews (IDIs, n= 37) with all health provider groups: Community health promoters (CHPs), health extension workers (HEWs), district supervisors and laboratory technicians were undertaken to obtain a detailed understanding of the experiences of providers in the community based tuberculosis package. These were complemented with cadre specific focus group discussions (n= 3). We used the framework approach for qualitative analysis.
Results
The key theme that emerged was the positive impact the community-based intervention had on vulnerable groups’ access to diagnosis, care and treatment for tuberculosis. Providers found the positive feedback from, and visible impact on, communities very motivating. Other themes related to motivation and performance included supervision and support; learning new skills; team problem solving/ addressing challenges and incentives. Against the backdrop of the Ethiopian Health Extension Programme (HEP), HEWs were successfully able to take on new tasks (collecting sputum and preparing smears) with additional training and appropriate support from supervisors, laboratory technicians and CHPs.
Conclusion
All categories of providers were motivated by the high visible impact of the community-based intervention on poor and vulnerable communities and households. HEWs role in the community-based intervention was supported and facilitated through the structures and processes established within the community-based intervention and the broader nation-wide Health Extension Programme. Within community based approaches there is need to develop context embedded strategies to support, sustain and motivate this critical cadre who play a pivotal role in linking health systems and rural communities
Lockdown Measures and their Impact on Single- and Two-age-structured Epidemic Model for the COVID-19 Outbreak in Mexico
The role of lockdown measures in mitigating COVID-19 in Mexico is investigated using a comprehensive
nonlinear ODE model. The model includes both asymptomatic and presymptomatic populations with the latter
leading to sickness (with recovery, hospitalization and death possibilities). We consider the situation involving
the imposed application of partial social distancing measures in the time series of interest and find optimal parametric fits to the time series of deaths (only), as well as to that of deaths and cumulative infections. We discuss
the merits and disadvantages of each approach, we interpret the parameters of the model and assess the realistic
nature of the parameters resulting from the optimization procedure. Importantly, we explore a model involving
two sub-populations (younger and older than a specific age), to more accurately reflect the observed impact as
concerns symptoms and behavior in different age groups. For definitiveness and to separate people that are (typically) in the active workforce, our partition of population is with respect to members younger vs. older than the
age of 65. The basic reproductive number of the model is computed for both the single- and the two-population
variant. Finally, we consider what would be the impact on the number of deaths and cumulative infections upon
imposition of partial lockdown (involving only the older population) and full lockdown (involving the entire
population)
Patient and community experiences of tuberculosis diagnosis and care within a community-based intervention in Ethiopia: a qualitative study
Background
The Ethiopian TB control programme relies on passive case finding of TB cases. The predominantly rural-based population in Ethiopia has limited access to health facilities creating barriers to TB services. An intervention package aimed to bring TB diagnosis and treatment services closer to communities has been implemented through partnership with health extension workers (HEWs). They undertook advocacy, communication and social mobilization (ACSM) activities, identified symptomatic individuals, collected sputum, prepared smears and fixed slides at community level. Field supervisors supported HEWs by delivering smeared slides to the laboratory, feeding back results to the HEWs and following up smear-negative cases. Patients diagnosed with TB initiated treatment in the community, they were supported by supervisors and HEWs through the local health post. Case notification increased from 64 to 127/100,000 population/year.
Methods
This qualitative study assessed community members’ treatment seeking behaviour and their perceptions of the intervention. In-depth interviews (n=36) were undertaken with participants in six districts. Participants were clients of the community-based intervention, currently on TB treatment or those screened negative for TB. Transcripts were translated to English and a thematic analytical framework was developed guided by the different steps symptomatic individuals take within the intervention package. Coding was done and queries run using NVivo software.
Results
Prior to the intervention many patients with chronic cough did not access TB services. Participants described difficulties they faced in accessing district level health facilities that required travel outside their communities. Giving sputum samples and receiving results from within their home communities was appreciated by all participants. The intervention had a high level of acceptability; particularly clear benefits emerged for poor women and men and those too weak to travel. Some participants appeared to prefer a diagnosis of TB, this is likely because receiving a negative smear microscopy result brought further uncertainty and necessitated seeking further investigation.
Conclusions
There is evidence rural populations with high levels of poverty, and in particular women, are at high risk of unmet health needs and undiagnosed TB. Embedding TB services within communities was an acceptable approach for vulnerable groups experiencing poor access to health facilities. In the Ethiopian context this approach can facilitate early diagnosis and improve treatment outcomes
PROPÓSITOS E REPRESENTAÇÕES DE ESTUDANTES UNIVERSITÁRIOS SOBRE O ENSINO SUPERIOR
PURPOSES AND REPRESENTATIONS OF COLLEGE STUDENTS ABOUT COLLEGE EDUCATION
Abstract: College time is a slice of the scholar education that has the purpose to provide the development of human capacities and potentials in the technical, scientific and personal aspects and the development of a conscious, participative and interventional citizenship. The article, a partial result of an international cross-sectional research, qualitative and quantitative, aims to introduce representations of college students about studying in the university and its hole in life purpose. The data was obtained through a transversal research with data collection via digital in 2019 with the participation of n=1112 students and n=10 countries. There were registered a variety of representations associated to the personal development and socioeconomic insertion.
Keywords: College Students. Representativity. Psychology of College Education. Life PurposeO ensino superior é uma esfera da educação escolar que tem como propósito atuar para favorecer o desenvolvimento dos potenciais e capacidades humanas nos aspectos técnicos, científicos, pessoais e desenvolvimento da cidadania consciente, participativa e interventiva. O artigo, resultado parcial de pesquisa internacional de cunho transversal, quanti-qualitativa, tem como objetivo apresentar representações de estudantes universitários sobre estudar na universidade e sua função no propósito de vida. Os dados foram obtidos por meio de pesquisa transversal com coleta de dados via digital em 2019 contando com participação de n=1112 estudantes de n=10 países. Foram registradas diferentes representações associadas ao desenvolvimento pessoal e inserção socioeconômica.
Palavras-chave: Estudantes universitários. Representações. Psicologia do Ensino superior. Propósito de vida.
 
Total and high molecular weight adiponectin have similar utility for the identification of insulin resistance
<p>Abstract</p> <p>Background</p> <p>Insulin resistance (IR) and related metabolic disturbances are characterized by low levels of adiponectin. High molecular weight adiponectin (HMWA) is considered the active form of adiponectin and a better marker of IR than total adiponectin. The objective of this study is to compare the utility of total adiponectin, HMWA and the HMWA/total adiponectin index (S<sub>A </sub>index) for the identification of IR and related metabolic conditions.</p> <p>Methods</p> <p>A cross-sectional analysis was performed in a group of ambulatory subjects, aged 20 to 70 years, in Mexico City. Areas under the receiver operator characteristic (ROC) curve for total, HMWA and the S<sub>A </sub>index were plotted for the identification of metabolic disturbances. Sensitivity and specificity, positive and negative predictive values, and accuracy for the identification of IR were calculated.</p> <p>Results</p> <p>The study included 101 men and 168 women. The areas under the ROC curve for total and HMWA for the identification of IR (0.664 <it>vs</it>. 0.669, <it>P </it>= 0.74), obesity (0.592 <it>vs</it>. 0.610, <it>P </it>= 0.32), hypertriglyceridemia (0.661 <it>vs</it>. 0.671, <it>P </it>= 0.50) and hypoalphalipoproteinemia (0.624 <it>vs</it>. 0.633, <it>P </it>= 0.58) were similar. A total adiponectin level of 8.03 μg/ml was associated with a sensitivity of 57.6%, a specificity of 65.9%, a positive predictive value of 50.0%, a negative predictive value of 72.4%, and an accuracy of 62.7% for the diagnosis of IR. The corresponding figures for a HMWA value of 4.25 μg/dl were 59.6%, 67.1%, 51.8%, 73.7% and 64.2%.</p> <p>The area under the ROC curve of the S<sub>A </sub>index for the identification of IR was 0.622 [95% CI 0.554-0.691], obesity 0.613 [95% CI 0.536-0.689], hypertriglyceridemia 0.616 [95% CI 0.549-0.683], and hypoalphalipoproteinemia 0.606 [95% CI 0.535-0.677].</p> <p>Conclusions</p> <p>Total adiponectin, HMWA and the S<sub>A </sub>index had similar utility for the identification of IR and metabolic disturbances.</p
Absolute spin-valve effect with superconducting proximity structures
We investigate spin dependent transport in hybrid
superconductor(S)--normal-metal(N)--ferromagnet(F) structures under conditions
of proximity effect. We demonstrate the feasibility of the absolute spin-valve
effect for a certain interval of voltages in a system consisting of two coupled
tri-layer structures. Our results are also valid for non-collinear magnetic
configurations of the ferromagnets.Comment: 1 TEX file, 2 Postscript files. Accepted for publication in Physical
Review Letter
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Dietary prophage inducers and antimicrobials: toward landscaping the human gut microbiome.
The approximately 1011 viruses and microbial cells per gram of fecal matter (dry weight) in the large intestine are important to human health. The responses of three common gut bacteria species, and one opportunistic pathogen, to 117 commonly consumed foods, chemical additives, and plant extracts were tested. Many compounds, including Stevia rebaudiana and bee propolis extracts, exhibited species-specific growth inhibition by prophage induction. Overall, these results show that various foods may change the abundances of gut bacteria by modulating temperate phage and suggests a novel path for landscaping the human gut microbiome
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