227 research outputs found
Spatial relationships between land-use, habitat, water quality and lotic macroinvertebrates in two Swiss catchments
We examined the influence of land-use, habitat, and water quality on the spatial distribution of aquatic macroinvertebrates in two human-dominated catchments in the Swiss Plateau (Gürbe, Mönchaltorfer Aa). Land-use in the Gürbe catchment was dominated by agriculture, whereas urban land-use was more common in the Mönchaltorfer Aa. Study sites in each catchment were characterized using measures of local habitat conditions, water quality parameters including water temperature, and organic matter resources. A strong longitudinal gradient in temperature, conductivity and nitrogen was evident among sites in the Gürbe catchment, although sites on a main tributary had a strong agricultural signature and deviated from this pattern. Percentage agricultural land-use in the Gürbe was strongly correlated with algal biomass and the water quality PCA axes associated with conductivity, nitrogen (axis-1) and temperature (axis-3). Spatial grouping of sites by water quality was less evident in the Mönchaltorfer Aa, except for a strong signal by wastewater treatment plant effluents and partial differences between upper and lower basin sites. Percentage forest and agricultural land-use in the Mönchaltorfer Aa were correlated with water quality PCA axis-2, being associated with phosphorus and temperature. Macroinvertebrate densities, taxonomic richness, and axis-1 from a non-metric multidimensional scaling analysis (NMDS) of taxonomic composition were significantly correlated with water quality PCA axis-1 in the Gürbe catchment. Here, macroinvertebrate densities and NMDS axis-1 scores based on taxon relative abundances and densities were correlated with land-use features. Spatial distances between sites also were related to site differences in macroinvertebrates, reflecting the strong longitudinal environmental gradient in the Gürbe. Taxonomic differences between water quality PCA site groups were less pronounced in the Mönchaltorfer Aa, although differences were significant for trichopterans, ephemeropterans, chironomids, gastropods and coleopterans. Here, NMDS axis-1 based on taxon relative abundances and densities was correlated with forest land-use. Spatial distances between sites were not evident in macroinvertebrate site differences, reflecting the less pronounced spatial and longitudinal patterns in environmental attributes in this catchment. Our results support the hypothesis that spatial distributions of macroinvertebrates are related to spatial relationships among environmental attributes like land-use, habitat, and water quality in human-dominated catchments that depend on river network complexity, a habitat-filtering template in line with ecological niche theory
How to make ecological models useful for environmental management
Understanding and predicting the ecological consequences of different management alternatives is becoming increasingly important to support environmental management decisions. Ecological models could contribute to such predictions, but in the past this was often not the case. Ecological models are often developed within research projects but are rarely used for practical applications. In this synthesis paper, we discuss how to strengthen the role of ecological modeling in supporting environmental management decisions with a focus on methodological aspects. We address mainly ecological modellers but also potential users of modeling results. Various modeling approaches can be used to predict the response of ecosystems to anthropogenic interventions, including mechanistic models, statistical models, and machine learning approaches. Regardless of the chosen approach, we outline how to better align the modeling to the decision making process, and identify six requirements that we believe are important to increase the usefulness of ecological models for management support, especially if management decisions need to be justified to the public. These cover: (i) a mechanistic understanding regarding causality, (ii) alignment of model input and output with the management decision, (iii) appropriate spatial and temporal resolutions, (iv) uncertainty quantification, (v) sufficient predictive performance, and (vi) transparent communication. We discuss challenges and synthesize suggestions for addressing these points. © 2019 The Author(s)This paper was initialized during a special session on Ecological Modelling at the 10th Symposium for European Freshwater Science 2017 ( http://www.sefs10.cz/ ) and further developed during the AQUACROSS project, funded by European Union's Horizon 2020 research and innovation programme (Grant agreement No. 642317 ). SD, SDL and MF were partly funded by the “GLANCE” project (Global Change Effects in River Ecosystems; 01 LN1320A) through the German Federal Ministry of Education and Research ( BMBF ). SDL has received additional funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 748625 . JML acknowledges the support of the Spanish Government through María de Maeztu excellence accreditation 2018–2021 (Ref. MDM-2017-0714 )
Does faculty development influence the quality of in-training evaluation reports in pharmacy?
An Anatomy Massive Open Online Course as a Continuing Professional Development Tool for Healthcare Professionals
Massive open online courses (MOOCs) remain a novel and under-evaluated learning tool within anatomical and medical education. This study aimed to provide valuable information by using an anatomy MOOC to investigate the demographic profile, patterns of engagement and self-perceived benefits to healthcare professionals. A 21-item survey aimed at healthcare professionals was embedded into the Exploring Anatomy: The Human Abdomen MOOC, in April 2016. The course attracted 2711 individual learners with 94 of these completing the survey, and 79 of those confirming they worked full- or part-time as healthcare professionals. Variations in use across healthcare profession (allied healthcare professional, nurse or doctor) were explored using a Fisher’s exact test to calculate significance across demographic, motivation and engagement items; one-way ANOVA was used to compare self-perceived benefits. Survey data revealed that 53.2% were allied healthcare professionals, 35.4% nurses and 11.4% doctors. Across all professions, the main motivation for enrolling was to learn new things in relation to their clinical practice, with a majority following the prescribed course pathway and utilising core, and clinically relevant, material. The main benefits were in relation to improving anatomy knowledge, which enabled better support for patients. This exploratory study assessing engagement and self-perceived benefits of an anatomy MOOC has shown a high level of ordered involvement, with some indicators suggesting possible benefits to patients by enhancing the subject knowledge of those enrolled. It is suggested that this type of learning tool should be further explored as an approach to continuing professional, and interprofessional, education
The reliability of in-training assessment when performance improvement is taken into account
During in-training assessment students are frequently assessed over a longer period of time and therefore it can be expected that their performance will improve. We studied whether there really is a measurable performance improvement when students are assessed over an extended period of time and how this improvement affects the reliability of the overall judgement. In-training assessment results were obtained from 104 students on rotation at our university hospital or at one of the six affiliated hospitals. Generalisability theory was used in combination with multilevel analysis to obtain reliability coefficients and to estimate the number of assessments needed for reliable overall judgement, both including and excluding performance improvement. Students’ clinical performance ratings improved significantly from a mean of 7.6 at the start to a mean of 7.8 at the end of their clerkship. When taking performance improvement into account, reliability coefficients were higher. The number of assessments needed to achieve a reliability of 0.80 or higher decreased from 17 to 11. Therefore, when studying reliability of in-training assessment, performance improvement should be considered
A-Site Residues Move Independently from P-Site Residues in all-Atom Molecular Dynamics Simulations of the 70S Bacterial Ribosome
The ribosome is a large macromolecular machine, and correlated motion between residues is necessary for coordinating function across multiple protein and RNA chains. We ran two all-atom, explicit solvent molecular dynamics simulations of the bacterial ribosome and calculated correlated motion between residue pairs by using mutual information. Because of the short timescales of our simulation (ns), we expect that dynamics are largely local fluctuations around the crystal structure. We hypothesize that residues that show coupled dynamics are functionally related, even on longer timescales. We validate our model by showing that crystallographic B-factors correlate well with the entropy calculated as part of our mutual information calculations. We reveal that A-site residues move relatively independently from P-site residues, effectively insulating A-site functions from P-site functions during translation
Optimization of Ribosome Structure and Function by rRNA Base Modification
BACKGROUND: Translating mRNA sequences into functional proteins is a fundamental process necessary for the viability of organisms throughout all kingdoms of life. The ribosome carries out this process with a delicate balance between speed and accuracy. This work investigates how ribosome structure and function are affected by rRNA base modification. The prevailing view is that rRNA base modifications serve to fine tune ribosome structure and function. METHODOLOGY/PRINCIPAL FINDINGS: To test this hypothesis, yeast strains deficient in rRNA modifications in the ribosomal peptidyltransferase center were monitored for changes in and translational fidelity. These studies revealed allele-specific sensitivity to translational inhibitors, changes in reading frame maintenance, nonsense suppression and aa-tRNA selection. Ribosomes isolated from two mutants with the most pronounced phenotypic changes had increased affinities for aa-tRNA, and surprisingly, increased rates of peptidyltransfer as monitored by the puromycin assay. rRNA chemical analyses of one of these mutants identified structural changes in five specific bases associated with the ribosomal A-site. CONCLUSIONS/SIGNIFICANCE: Together, the data suggest that modification of these bases fine tune the structure of the A-site region of the large subunit so as to assure correct positioning of critical rRNA bases involved in aa-tRNA accommodation into the PTC, of the eEF-1A•aa-tRNA•GTP ternary complex with the GTPase associated center, and of the aa-tRNA in the A-site. These findings represent a direct demonstration in support of the prevailing hypothesis that rRNA modifications serve to optimize rRNA structure for production of accurate and efficient ribosomes
SecM-Stalled Ribosomes Adopt an Altered Geometry at the Peptidyl Transferase Center
A structure of a ribosome stalled during translation of the SecM peptide provides insight into the mechanism by which the large subunit active site is inactivated
Scaffolded Active Learning: Nine Pedagogical Principles for Building a Modern Veterinary Curriculum
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