2,401 research outputs found

    A Systems Approach to Improving Tdap Immunization Within 5 Community-Based Family Practice Settings: Working Differently (and Better) by Transforming the Structure and Process of Care.

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    OBJECTIVES: We examined how family medicine clinic physicians and staff worked in collaborative teams to implement an automated clinical reminder to improve tetanus, diphtheria, and acellular pertussis (Tdap) booster vaccine administration and documentation. METHODS: A clinical reminder was developed at 5 University of Michigan family medicine clinics to identify patients 11 to 64 years old who were in need of the Tdap booster vaccine. Quality improvement cycles were used to improve clinic care processes. Immunization rates from 2008 to 2011 were compared with rates at 4 primary care control clinics. RESULTS: Vaccination rates among eligible patients increased from 15.5% to 47.3% within the family medicine clinics and from 14.1% to 30.2% within the control clinics. After adjustment for covariates, family medicine patients had a higher probability of vaccination than control patients during each measurement period (0.17 vs 0.15 at baseline, 0.53 vs 0.22 during year 1, and 0.50 vs 0.30 during year 2). CONCLUSIONS: Automated clinical reminders, when designed and implemented via a consensus-based framework that addresses the process of care, can dramatically improve provision of preventive health care

    Haploinsufficiency for BRCA1 is associated with normal levels of DNA nucleotide excision repair in breast tissue and blood lymphocytes

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    BACKGROUND: Screening mammography has had a positive impact on breast cancer mortality but cannot detect all breast tumors. In a small study, we confirmed that low power magnetic resonance imaging (MRI) could identify mammographically undetectable tumors by applying it to a high risk population. Tumors detected by this new technology could have unique etiologies and/or presentations, and may represent an increasing proportion of clinical practice as new screening methods are validated and applied A very important aspect of this etiology is genomic instability, which is associated with the loss of activity of the breast cancer-predisposing genes BRCA1 and BRCA2. In sporadic breast cancer, however, there is evidence for the involvement of a different pathway of DNA repair, nucleotide excision repair (NER), which remediates lesions that cause a distortion of the DNA helix, including DNA cross-links. CASE PRESENTATION: We describe a breast cancer patient with a mammographically undetectable stage I tumor identified in our MRI screening study. She was originally considered to be at high risk due to the familial occurrence of breast and other types of cancer, and after diagnosis was confirmed as a carrier of a Q1200X mutation in the BRCA1 gene. In vitro analysis of her normal breast tissue showed no differences in growth rate or differentiation potential from disease-free controls. Analysis of cultured blood lymphocyte and breast epithelial cell samples with the unscheduled DNA synthesis assay (UDS) revealed no deficiency in nucleotide excision repair (NER). CONCLUSION: As new breast cancer screening methods become available and cost effective, patients such as this one will constitute an increasing proportion of the incident population, so it is important to determine whether they differ from current patients in any clinically important ways. Despite her status as a BRCA1 mutation carrier, and her mammographically dense breast tissue, we did not find increased cell proliferation or deficient differentiation potential in her breast epithelial cells, which might have contributed to her cancer susceptibility. Although NER deficiency has been demonstrated repeatedly in blood samples from sporadic breast cancer patients, analysis of blood cultured lymphocytes and breast epithelial cells for this patient proves definitively that heterozygosity for inactivation of BRCA1 does not intrinsically confer this type of genetic instability. These data suggest that the mechanism of genomic instability driving the carcinogenic process may be fundamentally different in hereditary and sporadic breast cancer, resulting in different genotoxic susceptibilities, oncogene mutations, and a different molecular pathogenesis

    Cambial Phenology Informs Tree-Ring Analysis of Fire Seasonality in Coastal Plain Pine Savannas

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    © 2018, The Author(s). Understanding of historical fire seasonality should facilitate development of concepts regarding fire as an ecological and evolutionary process. In tree-ring based fire-history studies, the seasonality of fire scars can be classified based on the position of the fire scar within or between growth rings. Cambial phenology studies are needed to precisely relate a fire-scar position to months within a year because the timing of dormancy, earlywood production, and latewood production varies by species and location. We examined cambial phenology patterns of longleaf pine (Pinus palustris Mill.), slash pine (P. elliottii Engelm.), and South Florida slash pine (P. densa [Little & K.W Dorman] Silba) at sites in southern Georgia and south-central and northern Florida, USA. We developed long-term (2.5 yr to 12 yr) datasets of monthly growth and dormancy and determined when trees transitioned from producing early-wood to producing latewood each year. Most trees were dormant for a period of 1 to 2 months in the winter and transitioned from earlywood to latewood in June. Given the annual growth ring morphology of the pines that we studied and the timing of the lightning-fire season in our study area, we propose a new classification system for assigning seasonality to fire scars found in the three native upland pine species that we studied. This new system, which we name the Coastal Plain Pine System, accounts for the large proportion of latewood typical of these pines and includes a position (the transition position) that corresponds with the time of year when lightning fires occur most frequently. Our findings demonstrate how cambial phenology data can improve interpretation of fire-scar data for determining historical fire seasonality

    Biogeographical comparison of the emergent macrophyte, Sagittaria platyphylla in its native and introduced ranges

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    Understanding why some plant species become invasive is important to predict and prevent future weed threats and identify appropriate management strategies. Many hypotheses have been proposed to explain why plants become invasive, yet few studies have quantitatively compared plant and population parameters between native and introduced range populations to gain an objective perspective on the causes of plant invasion. The present study uses a biogeographical field survey to compare morphological and reproductive traits and abundance between the native range (USA) and two introduced ranges (Australia and South Africa) of Sagittaria platyphylla (Engelm.) J.G. Sm (Alismataceae), a highly invasive freshwater macrophyte. Introduced and native populations differed in sexual reproductive output with the number of achenes per fruiting head and individual achene weight found to be 40% and 50% greater in introduced populations respectively. However, no other morphological traits were found to be consistently different between the native and both introduced ranges, especially after taking into account differences in environmental conditions between the three ranges. Although populations in introduced regions were larger and occupied greater percentage cover, no differences in plant density were evident. Our results suggest that, apart from sexual reproduction, many of the trait patterns observed in S. platyphylla are influenced by environmental and habitat conditions within the native and invaded ranges. We conclude that the enemy release hypothesis best explains the results observed for sexual reproduction. In particular, we hypothesise that a release from natural enemies, specifically a pre-dispersal seed predator, may induce reproductive plasticity in S. platyphylla

    An ALMA Survey of M-dwarfs in the Beta Pictoris Moving Group with Two New Debris Disc Detections

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    Previous surveys in the far-infrared have found very few, if any, M-dwarf debris discs among their samples. It has been questioned whether M-dwarf discs are simply less common than earlier types, or whether the low detection rate derives from the wavelengths and sensitivities available to those studies. The highly sensitive, long wavelength Atacama Large Millimetre/submillimetre Array can shed light on the problem. This paper presents a survey of M-dwarf stars in the young and nearby Beta Pictoris Moving Group with ALMA at Band 7 (880\,μ\mum). From the observational sample we detect two new sub-mm excesses that likely constitute unresolved debris discs around GJ\,2006\,A and AT\,Mic\,A and model distributions of the disc fractional luminosities and temperatures. From the science sample of 36 M-dwarfs including AU\,Mic we find a disc detection rate of 4/36 or 11.13.3+7.4^{+7.4}_{-3.3}\% that rises to 23.15.5+8.3^{+8.3}_{-5.5}\% when adjusted for completeness. We conclude that this detection rate is consistent with the detection rate of discs around G and K type stars and that the disc properties are also likely consistent with earlier type stars. We additionally conclude that M-dwarf stars are not less likely to host debris discs, but instead their detection requires longer wavelength and higher sensitivity observations than have previously been employed.Comment: Accepted to MNRA

    Focusing and Diffraction of Light by Periodic Si Micropyramidal Arrays

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    This research was devoted to modeling of the optical properties of Si micropyramids aimed at designing optimal structures for applications as light concentrators in mid-wave infrared (MWIR) focal place arrays (FPAs). It is shown that completely different optical properties of such structures can be realized using two types of boundary conditions (BCs): i) periodical and ii) perfectly matched layer. The first type (periodical BC) allowed us to describe the Talbot effect under plane wave coherent illumination conditions. This effect was experimentally demonstrated in the proposed structures. The second type (perfectly matched layer BC) allows describing the optical properties of individual micropyramids concentrating or focusing light on the photodetector. The optimal geometries of micropyramids required for maximizing the intensity of photonic nanojets emerging from their truncated tips are determined.Comment: 4 pages, 5 figures, GOMACTech 202

    Uphill sprinting load – and force – velocity profiling : Assessment and potential applications

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    This study aimed to quantify the validity and reliability of load–velocity (LV) relationship of hill sprinting using a range of different hill gradients and to describe the effect of hill gradient on sprint performance. Twenty-four collegiate-level athletes performed a series of maximal sprints on either flat terrain or hills of gradients 5.2, 8.8 and 17.6%. Velocity–time curves were recorded using a radar device. LV relationships were established using the maximal velocity achieved in each sprinting condition, whilst force–velocity–power (FVP) profiles were established using only the flat terrain sprint. LV profiles were shown to be valid (R2 = 0.99) and reliable (TE < 4.4%). For every 1-degree increase in slope, subjects’ velocity decreased by 1.7 ± 0.1% on average. All the slopes used represented low resistance relative to the entire LV spectrum (<25% velocity loss). Subjects who exhibited greater horizontal force output at higher velocities on flat terrain were most affected by the gradient of the hill. Hills of gradients up to 17.6% do not provide sufficient resistance to optimize power development. However, such hills could be used to develop late-stage technical ability, due to the prolonged horizontally oriented body position that occurs as subjects attempt to overcome the acceleration due to gravity

    Collisions of particles in locally AdS spacetimes I. Local description and global examples

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    We investigate 3-dimensional globally hyperbolic AdS manifolds containing "particles", i.e., cone singularities along a graph Γ\Gamma. We impose physically relevant conditions on the cone singularities, e.g. positivity of mass (angle less than 2π2\pi on time-like singular segments). We construct examples of such manifolds, describe the cone singularities that can arise and the way they can interact (the local geometry near the vertices of Γ\Gamma). We then adapt to this setting some notions like global hyperbolicity which are natural for Lorentz manifolds, and construct some examples of globally hyperbolic AdS manifolds with interacting particles.Comment: This is a rewritten version of the first part of arxiv:0905.1823. That preprint was too long and contained two types of results, so we sliced it in two. This is the first part. Some sections have been completely rewritten so as to be more readable, at the cost of slightly less general statements. Others parts have been notably improved to increase readabilit

    Regulation of hepatic cardiolipin metabolism by TNFα: Implication in cancer cachexia

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    International audienceCardiolipin (CL) content accumulation leads to an increase in energy wasting in liver mitochondria in a rat model of cancer cachexia in which tumor necrosis factor alpha (TNFα) is highly expressed. In this study we investigated the mechanisms involved in liver mitochondria CL accumulation in cancer cachexia and examined if TNFα was involved in this process leading to mitochondrial bioenergetics alterations. We studied gene, protein expression and activity of the main enzymes involved in CL metabolism in liver mitochondria from a rat model of cancer cachexia and in HepaRG hepatocyte-like cells exposed to 20 ng/ml of TNFα for 12 h. Phosphatidylglycerolphosphate synthase (PGPS) gene expression was increased 2.3-fold (p < 0.02) and cardiolipin synthase (CLS) activity decreased 44% (p < 0.03) in cachectic rat livers compared to controls. CL remodeling enzymes monolysocardiolipin acyltransferase (MLCL AT-1) activity and tafazzin (TAZ) gene expression were increased 30% (p < 0.01) and 50% (p < 0.02), respectively, in cachectic rat livers compared to controls. Incubation of hepatocytes with TNFα increased CL content 15% (p < 0.05), mitochondrial oxygen consumption 33% (p < 0.05), PGPS gene expression 44% (p < 0.05) and MLCL AT-1 activity 20% (p < 0.05) compared to controls. These above findings strongly suggest that in cancer cachexia, TNFα induces a higher energy wasting in liver mitochondria by increasing CL content via upregulation of PGPS expression
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