38 research outputs found

    Shifts in Soil Structure, Biological, and Functional Diversity Under Long-Term Carbon Deprivation

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    Soil organic matter is composed of a variety of carbon (C) forms. However, not all forms are equally accessible to soil microorganisms. Deprivation of C inputs will cause changes in the physical and microbial community structures of soils; yet the trajectories of such changes are not clear. We assessed microbial communities using phospholipid fatty acid profiling, metabarcoding, CO2 emissions, and functional gene microarrays in a decade-long C deprivation field experiment. We also assessed changes in a range of soil physicochemical properties, including using X-ray Computed Tomography imaging to assess differences in soil structure. Two sets of soils were deprived of C inputs by removing plant inputs for 10 years and 1 year, respectively. We found a reduction in diversity measures, after 10 years of C deprivation, which was unexpected based on previous research. Fungi appeared to be most impacted, likely due to competition for scarce resources after exhausting the available plant material. This suggestion was supported by evidence of bioindicator taxa in non-vegetated soils that may directly compete with or consume fungi. There was also a reduction in copies of most functional genes after 10 years of C deprivation, though gene copies increased for phytase and some genes involved in decomposing recalcitrant C and methanogenesis. Additionally, soils under C deprivation displayed expected reductions in pH, organic C, nitrogen, and biomass as well as reduced mean pore size, especially in larger pores. However, pore connectivity increased after 10 years of C deprivation contrary to expectations. Our results highlight concurrent collapse of soil structure and biodiversity following long-term C deprivation. Overall, this study shows the negative trajectory of continuous C deprivation and loss of organic matter on a wide range of soil quality indicators and microorganisms

    Glastir Monitoring & Evaluation Programme. First year annual report

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    The Welsh Government has commissioned a comprehensive new ecosystem monitoring and evaluation programme to monitor the effects of Glastir, its new land management scheme, and to monitor progress towards a range of international biodiversity and environmental targets. A random sample of 1 km squares stratified by landcover types will be used both to monitor change at a national level in the wider countryside and to provide a backdrop against which intervention measures are assessed using a second sample of 1 km squares located in areas eligible for enhanced payments for advanced interventions. Modelling in the first year has forecast change based on current understanding, whilst a rolling national monitoring programme based on an ecosystem approach will provide an evidence-base for on-going, adaptive development of the scheme by Welsh Government. To our knowledge, this will constitute the largest and most in-depth ecosystem monitoring and evaluation programme of any member state of the European Union

    Non‐specific amplification compromises environmental DNA metabarcoding with COI

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    1. Metabarcoding extra-organismal DNA from environmental samples is now a key technique in aquatic biomonitoring and ecosystem health assessment. However, choice of genetic marker and primer set is a critical consideration when designing experiments, especially so when developing community standards and legislative frameworks. Mitochondrial cytochrome c oxidase subunit I (COI), the standard DNA barcode marker for animals, with its extensive reference library, taxonomic discriminatory power, and predictable sequence variation, is the natural choice for many metabarcoding applications such as the bulk sequencing of invertebrates. However, the overall utility of COI for environmental sequencing of targeted taxonomic groups has yet to be fully scrutinised. 2. Here, by using a case study of marine and freshwater fishes from the British Isles, we quantify the in silico performance of twelve mitochondrial primer pairs from COI, cytochrome b, 12S and 16S, in terms of reference library coverage, taxonomic discriminatory power, and primer universality. We subsequently test in vitro three COI primer pairs and one 12S pair for their specificity, reproducibility, and congruence with independent datasets derived from traditional survey methods at five estuarine and coastal sites in the English Channel and North Sea coast. 3. Our results show that for aqueous extra-organismal DNA at low template concentrations, both metazoan and fish-targeted COI primers perform poorly in comparison to 12S, exhibiting low levels of reproducibility due to non-specific amplification of prokaryotic and non-target eukaryotic DNAs. 4. An ideal metabarcode would have an extensive reference library for which custom primer sets can be designed for either broad assessments of biodiversity or taxon specific surveys, but unfortunately, low primer specificity hinders the use of COI, while the paucity of reference sequences is problematic for 12S. The latter, however, can be mitigated by expanding the concept of DNA barcodes to include whole mitochondrial genomes generated by genome-skimming existing tissue collections

    Communication within low income families and the management of asthma

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    This study examines the effects of communication between low income urban parents and children about a chronic disease on the extent to which parent and child effectively manage the illness. Four asthma communication factors were identified by principal component analysis. We found that mothers whose preferred language was Spanish, and families who were not receiving public assistance, communicated more frequently about asthma in general. Spanish speaking mothers and their children communicated more about potential home treatments for asthma, and the more adults in the household the less there was communication about the need for emergency services for asthma. Mothers who preferred to speak Spanish had higher levels of management of the most recent asthma attack. Those whose children communicated with them about asthma in general were higher level managers. Children who influenced their parents' decisions about school attendance, and those whose mothers were more highly educated, had higher levels of asthma attack management. More educated mothers, ones whose children were younger at the time of the onset of asthma, and ones who received public assistance, were more involved "in general" in their child's asthma care.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28643/1/0000458.pd

    A communal catalogue reveals Earth's multiscale microbial diversity

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    Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe

    A communal catalogue reveals Earth’s multiscale microbial diversity

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    Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth’s microbial diversity

    Distinguishing reality from fantasy in adults with autism spectrum disorder: Evidence from eye movements and reading

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    Understanding fictional events requires one to distinguish reality from fantasy, and thus engages high-level processes including executive functions and imagination, both of which are impaired in autism spectrum disorder (ASD). We examined how adults with and without ASD make sense of reality-violating fantasy narratives by testing real-time understanding of counterfactuals. Participants were eye-tracked as they read narratives that depicted novel counterfactual scenarios that violate reality (e.g. “If margarine contained detergent, Mum could use margarine in her washing/baking”, Experiment 1), or counterfactual versions of known fictional worlds (e.g. “If Harry Potter had lost all his magic powers, he would use his broom to sweep/fly”, Experiment 2). Results revealed anomaly detection effects in the early moments of processing (immediately in Experiment 1, and from the post-critical region in Experiment 2), which were not modulated by group. We discuss these findings in relation to the constraints from real-world and fantasy contexts that compete to influence language comprehension, and identify a dissociation between ToM impairments and counterfactual processing abilities

    Running enhances spatial pattern separation in mice

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    Increasing evidence suggests that regular exercise improves brain health and promotes synaptic plasticity and hippocampal neurogenesis. Exercise improves learning, but specific mechanisms of information processing influenced by physical activity are unknown. Here, we report that voluntary running enhanced the ability of adult (3 months old) male C57BL/6 mice to discriminate between the locations of two adjacent identical stimuli. Improved spatial pattern separation in adult runners was tightly correlated with increased neurogenesis. In contrast, very aged (22 months old) mice had impaired spatial discrimination and low basal cell genesis that was refractory to running. These findings suggest that the addition of newly born neurons may bolster dentate gyrus-mediated encoding of fine spatial distinctions

    Human Cord Blood Progenitors with High Aldehyde Dehydrogenase Activity Improve Vascular Density in a Model of Acute Myocardial Infarction

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    Human stem cells from adult sources have been shown to contribute to the regeneration of muscle, liver, heart, and vasculature. The mechanisms by which this is accomplished are, however, still not well understood. We tested the engraftment and regenerative potential of human umbilical cord blood-derived ALDH(hi)Lin(-), and ALDH(lo)Lin(-) cells following transplantation to NOD/SCID or NOD/SCID beta2m null mice with experimentally induced acute myocardial infarction. We used combined nanoparticle labeling and whole organ fluorescent imaging to detect human cells in multiple organs 48 hours post transplantation. Engraftment and regenerative effects of cell treatment were assessed four weeks post transplantation. We found that ALDH(hi)Lin(-) stem cells specifically located to the site of injury 48 hours post transplantation and engrafted the infarcted heart at higher frequencies than ALDH(lo)Lin(-) committed progenitor cells four weeks post transplantation. We found no donor derived cardiomyocytes and few endothelial cells of donor origin. Cell treatment was not associated with any detectable functional improvement at the four week endpoint. There was, however, a significant increase in vascular density in the central infarct zone of ALDH(hi)Lin(-) cell-treated mice, as compared to PBS and ALDH(lo)Lin(-) cell-treated mice. CONCLUSIONS: Our data indicate that adult human stem cells do not become a significant part of the regenerating tissue, but rapidly home to and persist only temporarily at the site of hypoxic injury to exert trophic effects on tissue repair thereby enhancing vascular recovery
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