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BioTIME: A database of biodiversity time series for the Anthropocene.
MotivationThe BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.Main types of variables includedThe database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grainBioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2).Time period and grainBioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.Major taxa and level of measurementBioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.Software format.csv and .SQL
Intra-Organ Variation in Age-Related Mutation Accumulation in the Mouse
Using a transgenic mouse model harboring chromosomally integrated lacZ mutational target genes, we previously demonstrated that mutations accumulate with age much more rapidly in the small intestine than in the brain. Here it is shown that in the small intestine point mutations preferentially accumulate in epithelial cells of the mucosa scraped off the underlying serosa. The mucosal cells are the differentiated villus cells that have undergone multiple cell divisions. A smaller age-related increase, also involving genome rearrangements, was observed in the serosa, which consists mainly of the remaining crypts and non-dividing smooth muscle cells. In the brain we observed an accumulation of only point mutations in no other areas than hypothalamus and hippocampus. To directly test for cell division as the determining factor in the generation of point mutations we compared mutation induction between mitotically active and quiescent embryonic fibroblasts from the same lacZ mice, treated with either UV (a point mutagen) or hydrogen peroxide (a clastogen). The results indicate that while point mutations are highly replication-dependent, genome rearrangements are as easily induced in non-dividing cells as in mitotically active ones. This strongly suggests that the point mutations found to have accumulated in the mucosal part of the small intestine are the consequence of replication errors. The same is likely true for point mutations accumulating in hippocampus and hypothalamus of the brain since neurogenesis in these two areas continues throughout life. The observed intra-organ variation in mutation susceptibility as well as the variation in replication dependency of different types of mutations indicates the need to not only extend observations made on whole organs to their sub-structures but also take the type of mutations and mitotic activity of the cells into consideration. This should help elucidating the impact of genome instability and its consequences on aging and disease
Age- and Temperature-Dependent Somatic Mutation Accumulation in Drosophila melanogaster
Using a transgenic mouse model harboring a mutation reporter gene that can be efficiently recovered from genomic DNA, we previously demonstrated that mutations accumulate in aging mice in a tissue-specific manner. Applying a recently developed, similar reporter-based assay in Drosophila melanogaster, we now show that the mutation frequency at the lacZ locus in somatic tissue of flies is about three times as high as in mouse tissues, with a much higher fraction of large genome rearrangements. Similar to mice, somatic mutations in the fly also accumulate as a function of age, but they do so much more quickly at higher temperature, a condition which in invertebrates is associated with decreased life span. Most mutations were found to accumulate in the thorax and less in abdomen, suggesting the highly oxidative flight muscles as a possible source of genotoxic stress. These results show that somatic mutation loads in short-lived flies are much more severe than in the much longer-lived mice, with the mutation rate in flies proportional to biological rather than chronological aging
Evaluation of health care providers’ role transition and satisfaction in hospital-at-home for chronic obstructive pulmonary disease exacerbations: a survey study
__Abstract__
__Background__: Hospital-at-home is an accepted alternative for usual hospital treatment for patients with a Chronic
Obstructive Pulmonary Disease (COPD) exacerbation. The introduction of hospital-at-home may lead to changes in
health care providers’ roles and responsibilit
Ambulatory health service users' experience of waiting time and expenditure and factors associated with the perception of low quality of care in Mexico
<p>Abstract</p> <p>Background</p> <p>A principal reason for low use of public health care services is the perception of inferior quality of care. Studying health service user (HSU) experiences with their care and their perception of health service quality is critical to understanding health service utilization. The aim of this study was to define reference points for some aspects of health care quality and to analyze which HSU experiences resulted in perceptions of overall low quality of care.</p> <p>Methods</p> <p>Data from the National Health Survey 2006 were used to compare the experiences of HSUs with their ambulatory care at Ministry of Health and affiliated institutions (MOH), social security institutions (SSI) and private institutions (PrivI). Reference points of quality of care related to waiting time and expenditure were defined for each of the three types of institutions by analyzing HSU experiences rated as 'acceptable'. A multivariable logistic regression model was used to identify the principal factors associated with the general perception of low quality of care.</p> <p>Results</p> <p>A total of 11,959 HSUs were included in the analysis, of whom 37.6% (n = 4,500) HSUs received care at MOH facilities; 31.2% (n = 3,730) used SSI and 31.2% (n = 3,729) PrivI. An estimated travel and waiting time of 10 minutes respectively was rated as acceptable by HSUs from all institutions. The differences between the waiting time rated as acceptable and the actual waiting time were the largest for SSI (30 min) in comparison to MoH (20 min) and PrivI (5 min) users. The principal factors associated with an overall perception of low quality of care are type of institution (OR 4.36; 95% CI 2.95-6.44), waiting time (OR 3.20; 95% CI 2.35-4.35), improvement of health after consultation (OR 2.93; CI 2.29-3.76) and consultation length of less than 20 minutes (2.03; 95% CI 1.60-2.57).</p> <p>Conclusions</p> <p>The reference points derived by the HSUs' own ratings are useful in identifying where quality improvements are required. Prioritizing the reduction of waiting times and improving health status improvement after consultation would increase overall quality of care ratings.</p
The 1.2 A resolution crystal structure of TcpG, the Vibrio cholerae DsbA disulfide-forming protein required for pilus and cholera-toxin production
The enzyme TcpG is a periplasmic protein produced by the Gram-negative pathogen Vibrio cholerae. TcpG is essential for the production of ToxR-regulated proteins, including virulence-factor pilus proteins and cholera toxin, and is therefore a target for the development of a new class of anti-virulence drugs. Here, the 1.2 Å resolution crystal structure of TcpG is reported using a cryocooled crystal. This structure is compared with a previous crystal structure determined at 2.1 Å resolution from data measured at room temperature. The new crystal structure is the first DsbA crystal structure to be solved at a sufficiently high resolution to allow the inclusion of refined H atoms in the model. The redox properties of TcpG are also reported, allowing comparison of its oxidoreductase activity with those of other DSB proteins. One of the defining features of the Escherichia coli DsbA enzyme is its destabilizing disulfide, and this is also present in TcpG. The data presented here provide new insights into the structure and redox properties of this enzyme, showing that the binding mode identified between E. coli DsbB and DsbA is likely to be conserved in TcpG and that the [beta]5-[alpha]7 loop near the proposed DsbB binding site is flexible, and suggesting that the tense oxidized conformation of TcpG may be the consequence of a short contact at the active site that is induced by disulfide formation and is relieved by reduction
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