576 research outputs found
Submarine glacial landforms on the Bay of Fundyânorthern Gulf of Maine continental shelf
Author Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here by permission of Geological Society of London for personal use, not for redistribution. The definitive version was published in Geological Society, London, Memoirs 46 (2016): 429-436, doi:10.1144/M46.154.The Bay of Fundyânorthern Gulf of Maine region surrounds the southern part of Nova Scotia,
encompassing, from west to east, the Bay of Fundy, Grand Manan Basin, German Bank, Browns
Bank, Northeast Channel, and northeastern Georges Bank (Fig. 1a). During the last glacial
maximum (~24â20 14C ka BP), the southeast margin of the Laurentide Ice Sheet (LIS) occupied
the study area, the rest of the Gulf of Maine, and the continental Scotian Shelf off Atlantic
Canada (see Dyke et al. 2002, Fig. 1; Hundert & Piper 2008, Fig. 16; Shaw et al. 2006, Fig. 8).
Early mapping of the glaciated region on the Scotian Shelf using side-scan sonar imagery and
seismic reflection profiles revealed topographic features interpreted to be recessional moraines
indicative of retreat of the LIS (King et al. 1972; King 1996; Stea et al. 1998). Subsequently,
multibeam sonar seafloor mapping of local-scale glacial landforms on the inner Scotian Shelf off
Halifax, Nova Scotia (Fig. 1a) provided further information on the dynamics of the advance and
retreat of the ice sheet (Loncarevic et al. 1994). Interpretation of seismic reflection profiles
across Georges Bank revealed that the surficial sediment is a veneer of glacial debris transported
to Georges Bank by the LIS during the late Pleistocene from continental areas to the north
(Shepard et al. 1934; Knott & Hoskins 1968; Oldale & Uchupi 1970; Schlee 1973; Schlee &
Pratt 1970; Twichell et al. 1987; Fader et al. 1988). Recent high-resolution multibeam sonar
surveys of German Bank and the Bay of Fundy mapped a complex of ice-advance and ice-retreat
features attributed to the activity of the LIS (Todd et al. 2007; Todd & Shaw 2012).2017-11-0
A spectral adjustment for spatial confounding
Adjusting for an unmeasured confounder is generally an intractable problem, but in the spatial setting it may be possible under certain conditions. In this paper, we derive necessary conditions on the coherence between the treatment variable of interest and the unmeasured confounder that ensure the causal effect of the treatment is estimable. We specify our model and assumptions in the spectral domain to allow for different degrees of confounding at different spatial resolutions. The key assumption that ensures identifiability is that confounding present at global scales dissipates at local scales. We show that this assumption in the spectral domain is equivalent to adjusting for global-scale confounding in the spatial domain by adding a spatially smoothed version of the treatment variable to the mean of the response variable. Within this general framework, we propose a sequence of confounder adjustment methods that range from parametric adjustments based on the Matérn coherence function to more robust semiparametric methods that use smoothing splines. These ideas are applied to areal and geostatistical data for both simulated and real datasets
Comparison of embedded and added motor imagery training in patients after stroke: Results of a randomised controlled pilot trial
Copyright @ 2012 Schuster et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Motor imagery (MI) when combined with physiotherapy can offer functional benefits after stroke. Two MI integration strategies exist: added and embedded MI. Both approaches were compared when learning a complex motor task (MT): âGoing down, laying on the floor, and getting up againâ. Methods: Outpatients after first stroke participated in a single-blinded, randomised controlled trial with MI embedded into physiotherapy (EG1), MI added to physiotherapy (EG2), and a control group (CG). All groups participated in six physiotherapy sessions. Primary study outcome was time (sec) to perform the motor task at pre and post-intervention. Secondary outcomes: level of help needed, stages of MT-completion, independence, balance, fear of falling (FOF), MI ability. Data were collected four times: twice during one week baseline phase (BL, T0), following the two week intervention (T1), after a two week follow-up (FU). Analysis of variance was performed. Results: Thirty nine outpatients were included (12 females, age: 63.4 ± 10 years; time since stroke: 3.5 ± 2 years; 29 with an ischemic event). All were able to complete the motor task using the standardised 7-step procedure and reduced FOF at T0, T1, and FU. Times to perform the MT at baseline were 44.2 ± 22s, 64.6 ± 50s, and 118.3 ± 93s for EG1 (N = 13), EG2 (N = 12), and CG (N = 14). All groups showed significant improvement in time to complete the MT (p < 0.001) and degree of help needed to perform the task: minimal assistance to supervision (CG) and independent performance (EG1+2). No between group differences were found. Only EG1 demonstrated changes in MI ability over time with the visual indicator increasing from T0 to T1 and decreasing from T1 to FU. The kinaesthetic indicator increased from T1 to FU. Patients indicated to value the MI training and continued using MI for other difficult-to-perform tasks. Conclusions: Embedded or added MI training combined with physiotherapy seem to be feasible and benefi-cial to learn the MT with emphasis on getting up independently. Based on their baseline level CG had the highest potential to improve outcomes. A patient study with 35 patients per group could give a conclusive answer of a superior MI integration strategy.The research project was partially funded by the Gottfried und Julia Bangerter-Rhyner Foundation
Revascularization of Chronic Hibernating Myocardium Stimulates Myocyte Proliferation and Partially Reverses Chronic Adaptations to Ischemia
AbstractBackgroundThe time course and extent of recovery after revascularization of viable dysfunctional myocardium are variable. Although fibrosis is a major determinant, myocyte structural and molecular remodeling may also play important roles.ObjectivesThis study sought to determine whether persistent myocyte loss and/or irreversibility of protein changes that develop in hibernating myocardium have an impact on functional recovery in the absence of infarction.MethodsSwine implanted with a chronic left anterior descending artery (LAD) stenosis to produce hibernating myocardium underwent percutaneous revascularization, with serial functional recovery evaluated for 1 month (n = 12). Myocardial tissue was evaluated to assess myocyte size, nuclear density, and proliferation indexes in comparison with those of normal animals and nonrevascularized controls. Proteomic analysis by 2-dimensional differential in-gel electrophoresis was used to determine the reversibility of molecular adaptations of hibernating myocytes.ResultsAt 3 months, physiological features of hibernating myocardium were confirmed, with depressed LAD wall thickening and no significant infarction. Revascularization normalized LAD flow reserve, with no immediate change in LAD wall thickening. Regional LAD wall thickening slowly improved but remained depressed 1 month postâpercutaneous coronary intervention. Surprisingly, revascularization was associated with histological evidence of myocytes re-entering the growth phase of the cell cycle and increases in the number of c-Kit+ cells. Myocyte nuclear density returned to normal, whereas regional myocyte hypertrophy regressed. Proteomic analysis demonstrated heterogeneous effects of revascularization. Up-regulated stress and cytoskeletal proteins normalized, whereas reduced contractile and metabolic proteins persisted.ConclusionsDelayed recovery of hibernating myocardium in the absence of scar may reflect persistent reductions in the amounts of contractile and metabolic proteins. Although revascularization appeared to stimulate myocyte proliferation, the persistence of small immature myocytes may have contributed to delayed functional recovery
Reporting guidelines for health research: protocol for a cross-sectional analysis of the EQUATOR Network Library
INTRODUCTION: Transparency and completeness of health research is highly variable, with important deficiencies in the reporting of methods and results of studies. Reporting guidelines aim to improve transparency and quality of research reports, and are often developed by consortia of journal editors, peer reviewers, authors, consumers and other key stakeholders. The objective of this study will be to investigate the characteristics of scientific collaboration among developers and the citation metrics of reporting guidelines of health research. METHODS AND ANALYSIS: This is the study protocol for a cross-sectional analysis of completed reporting guidelines indexed in the Enhancing the QUAlity and Transparency Of health Research Network Library. We will search PubMed/MEDLINE and the Web of Science. Screening, selection and data abstraction will be conducted by one researcher and verified by a second researcher. Potential discrepancies will be resolved via discussion. We will include published papers of reporting guidelines written in English. Published papers will have to meet the definition of a reporting guideline related to health research (eg, a checklist, flow diagram or explicit text), with no restrictions by study design, medical specialty, disease or condition. Raw data from each included paper (including title, publication year, journal, subject category, keywords, citations, and the authors' names, author's affiliated institution and country) will be exported from the Web of Science. Descriptive analyses will be conducted (including the number of papers, citations, authors, countries, journals, keywords and main collaboration metrics). We will identify the most prolific authors, institutions, countries, journals and the most cited papers. Network analyses will be carried out to study the structure of collaborations. ETHICS AND DISSEMINATION: No ethical approval will be required. Findings from this study will be published in peer-reviewed journals. All data will be deposited in a cross-disciplinary public repository. It is anticipated the study findings could be relevant to a variety of audiences.Instituto de Salud Carlos III; Australian National Health and Medical Research Council; Canadian Institutes of Health Research; Universidad de Ottawa. FC-L and RT-S are supported by the Institute of Health Carlos III/CIBERSAM. MJP is supported by an Australian National Health and Medical Research Council Early Career Fellowship (1088535). BH is supported by a New Investigator Award from the Canadian Institutes of Health Research and the Drug Safety and Effectiveness Network. MR is supported by the Institute of Health Carlos III/Spanish Health Services Research on Chronic Patients Network (REDISSEC). DM is supported by a University Research Chair, University of Ottawa.S
Quiet Supersonic Flights 2018 (QSF18) Test: Galveston, Texas Risk Reduction for Future Community Testing with a Low-Boom Flight Demonstration Vehicle
The Quiet Supersonic Flights 2018 (QSF18) Program was designed to develop tools and methods for demonstration of overland supersonic flight with an acceptable sonic boom, and collect a large dataset of responses from a representative sample of the population. Phase 1 provided the basis for a low amplitude sonic boom testing in six different climate regions that will enable international regulatory agencies to draft a noise-based standard for certifying civilian supersonic overland flight. Phase 2 successfully executed a large scale test in Galveston, Texas, developed well documented data sets, calculated dose response relationships, yielded lessons, and identified future risk reduction activities
Intrachromosomal homologous recombination between inverted amplicons on opposing Y-chromosome arms
Amplicons â large, nearly identical repeats in direct or inverted orientation â are abundant in the male-specific region of the human Y chromosome (MSY) and provide targets for intrachromosomal non-allelic homologous recombination (NAHR). Thus far, NAHR events resulting in deletions, duplications, inversions, or isodicentric chromosomes have been reported only for amplicon pairs located exclusively on the short arm (Yp) or the long arm (Yq). Here we report our finding of four men with Y chromosomes that evidently formed by intrachromosomal NAHR between inverted repeat pairs comprising one amplicon on Yp and one amplicon on Yq. In two men with spermatogenic failure, sister-chromatid crossing-over resulted in pseudoisoYp chromosome formation and loss of distal Yq. In two men with normal spermatogenesis, intrachromatid crossing-over generated pericentric inversions. These findings highlight the recombinogenic nature of the MSY, as intrachromosomal NAHR occurs for nearly all Y-chromosome amplicon pairs, even those located on opposing chromosome arms.National Institutes of Health (U.S.)Netherlands Organization for Scientific ResearchAcademic Medical Center (University of Amsterdam
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