819 research outputs found

    Comparing the retinal structures and functions in two species of gulls (Larus delawarensis and Larus modestus) with significant nocturnal behaviours

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    AbstractRing-billed gulls (Larus delawarensis) and gray gulls (Larus modestus) are two species active both by day and night. We have investigated the retinal adaptations that allow the diurnal and nocturnal behaviours of these two species. Electroretinograms and histological analyses show that both species have a duplex retina in which cones outnumber rods, but the number of rods appears sufficient to provide vision at night. Their retinas respond over the same scotopic dynamic range of 3.4logcdm−2, which encompasses all of the light levels occurring at night in their photic environment. The amplitudes of the scotopic saturated a- and b-wave responses as well as the photopic saturated b-wave response and the photopic sensitivity parameter S are however higher in ring-billed gulls than in gray gulls. Moreover, the process of dark adaptation is about 30min faster in gray gulls than in ring-billed gulls. Our results suggest that both species have acquired in the course of their evolution functional adaptations that can be related to their specific photic environment

    Andreev reflection at QGP/CFL interface

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    In this letter we address the question of the phenomena of Andreev reflection between the cold quark-gluon plasma phase and CFL color superconductor. We show that there are two different types of reflections connected to the structure of the CFL phase. We also calculate the probability current at the interface and we show that it vanishes for energy of scattering quarks below the superconducting gap.Comment: 6 pages, 1 figure. Minor changes in the "Conclusions

    Bolstering Confidence in Obesity Prevention and Treatment Counseling for Resident and Community Pediatricians

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    Objective- To assess whether equipping resident pediatricians and community pediatricians with both training and practical tools improves their perceived confidence, ease, and frequency of obesity related counseling to patients. Methods- In 2005-2006, resident pediatricians (n = 49) and community pediatricians (n=18) received training regarding three evidence-based obesity prevention/treatment tools and responded to pre-and post-intervention questionnaires. We analyzed changes in reported mean confidence, ease, and frequency of dietary, physical activity, and weight status counseling. Results- Baseline scores of confidence, ease, and frequency of counseling were higher in community pediatricians than residents. Mean scores increased significantly in the combined group, among residents only, and trended towards improvement in the community pediatricians following the intervention. Means for "control" questions were unchanged. Conclusion- Training and tools for residents and community pediatricians improved their confidence, ease, and frequency of obesity-related counseling. Practice Implications- This study demonstrates that when feasible and appropriate tools and training were provided through a simple intervention, physicians gained confidence and ease and increased their counseling frequency. The results here suggest that widespread implementation of such educational interventions for community practitioners and practitioners in training could change the way physicians counsel patients to prevent the often frustrating problem of childhood obesity. Originally published Patient Education and Counseling, Vol. 73, No. 2, Nov 200

    Lactobacillus casei Abundance Is Associated with Profound Shifts in the Infant Gut Microbiome

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    Colonization of the infant gut by microorganisms over the first year of life is crucial for development of a balanced immune response. Early alterations in the gastrointestinal microbiota of neonates has been linked with subsequent development of asthma and atopy in older children. Here we describe high-resolution culture-independent analysis of stool samples from 6-month old infants fed daily supplements of Lactobacillus casei subsp. Rhamnosus (LGG) or placebo in a double-blind, randomized Trial of Infant Probiotic Supplementation (TIPS). Bacterial community composition was examined using a high-density microarray, the 16S rRNA PhyloChip, and the microbial assemblages of infants with either high or low LGG abundance were compared. Communities with high abundance of LGG exhibited promotion of phylogenetically clustered taxa including a number of other known probiotic species, and were significantly more even in their distribution of community members. Ecologically, these aspects are characteristic of communities that are more resistant to perturbation and outgrowth of pathogens. PhyloChip analysis also permitted identification of taxa negatively correlated with LGG abundance that have previously been associated with atopy, as well as those positively correlated that may prove useful alternative targets for investigation as alternative probiotic species. From these findings we hypothesize that a key mechanism for the protective effect of LGG supplementation on subsequent development of allergic disease is through promotion of a stable, even, and functionally redundant infant gastrointestinal community

    Magnetically Decorated Multiwalled Carbon Nanotubes as Dual MRI and SPECT Contrast Agents

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    Carbon nanotubes (CNTs) have been proposed as one of the most promising nanomaterials to be used in biomedicine for their applications in drug/gene delivery as well as biomedical imaging. The present study developed radio-labeled iron oxide decorated multi-walled CNTs (MWNT) as dual magnetic resonance (MR) and single photon emission computed tomography (SPECT) imaging agents. Hybrids containing different amounts of iron oxide were synthesized by in situ generation. Physicochemical characterisations revealed the presence of superparamagnetic iron oxide nanoparticles (SPION) granted the magnetic properties of the hybrids. Further comprehensive examinations including high resolution transmission electron microscopy (HRTEM), fast Fourier transform simulations (FFT), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) assured the conformation of prepared SPION as Îł-Fe(2)O(3). High r(2) relaxivities were obtained in both phantom and in vivo MRI compared to the clinically approved SPION Endorem(ÂŽ). The hybrids were successfully radio-labeled with technetium-99m through a functionalized bisphosphonate and enabled SPECT/CT imaging and Îł-scintigraphy to quantitatively analyze the biodistribution in mice. No abnormality was found by histological examination and the presence of SPION and MWNT were identified by Perls stain and Neutral Red stain, respectively. TEM images of liver and spleen tissues showed the co-localization of SPION and MWNT within the same intracellular vesicles, indicating the in vivo stability of the hybrids after intravenous injection. The results demonstrated the capability of the present SPION-MWNT hybrids as dual MRI and SPECT contrast agents for in vivo use

    How much do health care providers value a community-based asthma care program? – a survey to collect their opinions on the utilities of and barriers to its uptake

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    <p>Abstract</p> <p>Background</p> <p>A comprehensive asthma care program (ACP) based on Canadian Asthma Consensus Guidelines was implemented in 8 primary care sites in Ontario, Canada. A survey was distributed to health care providers' (HCPs) to collect their opinions on the utilities of and barriers to the uptake of the ACP.</p> <p>Methods</p> <p>A 39-item self-administered survey was mailed to 184 HCPs and support staff involved in delivering the ACP at the end of implementation. The items were presented in mixed formats with most items requiring responses on a five-point Likert scale. Distributions of responses were analyzed and compared across types of HCPs and sites.</p> <p>Results</p> <p>Of the 184 surveys distributed, 108 (59%) were returned, and of that, 83 were completed by HCPs who had clinical contact with the patients. Overall, 95% of the HCPs considered the ACP useful for improving asthma care management. Most HCPs favored using the asthma care map (72%), believed it decreased uncertainties and variations in patient management (91%), and considered it a convenient and reliable source of information (86%). The most commonly reported barrier was time required to complete the asthma care map. Over half of the HCPs reported challenges to using spirometry, while almost 40% identified barriers to using the asthma action plan.</p> <p>Conclusion</p> <p>Contrary to the notion that physicians believe that guidelines foster cookbook medicine, our study showed that HCPs believed that the ACP offered an effective and reliable approach for enhancing asthma care and management in primary care.</p

    The breadth of primary care: a systematic literature review of its core dimensions

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    Background: Even though there is general agreement that primary care is the linchpin of effective health care delivery, to date no efforts have been made to systematically review the scientific evidence supporting this supposition. The aim of this study was to examine the breadth of primary care by identifying its core dimensions and to assess the evidence for their interrelations and their relevance to outcomes at (primary) health system level. Methods: A systematic review of the primary care literature was carried out, restricted to English language journals reporting original research or systematic reviews. Studies published between 2003 and July 2008 were searched in MEDLINE, Embase, Cochrane Library, CINAHL, King's Fund Database, IDEAS Database, and EconLit. Results: Eighty-five studies were identified. This review was able to provide insight in the complexity of primary care as a multidimensional system, by identifying ten core dimensions that constitute a primary care system. The structure of a primary care system consists of three dimensions: 1. governance; 2. economic conditions; and 3. workforce development. The primary care process is determined by four dimensions: 4. access; 5. continuity of care; 6. coordination of care; and 7. comprehensiveness of care. The outcome of a primary care system includes three dimensions: 8. quality of care; 9. efficiency care; and 10. equity in health. There is a considerable evidence base showing that primary care contributes through its dimensions to overall health system performance and health. Conclusions: A primary care system can be defined and approached as a multidimensional system contributing to overall health system performance and health

    A hospital-site controlled intervention using audit and feedback to implement guidelines concerning inappropriate treatment of catheter-associated asymptomatic bacteriuria

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    <p>Abstract</p> <p>Background</p> <p>Catheter-associated urinary tract infection (CAUTI) is one of the most common hospital-acquired infections. However, many cases treated as hospital-acquired CAUTI are actually asymptomatic bacteriuria (ABU). Evidence-based guidelines recommend that providers neither screen for nor treat ABU in most catheterized patients, but there is a significant gap between these guidelines and clinical practice. Our objectives are (1) to evaluate the effectiveness of an audit and feedback intervention for increasing guideline-concordant care concerning catheter-associated ABU and (2) to measure improvements in healthcare providers' knowledge of and attitudes toward the practice guidelines associated with the intervention.</p> <p>Methods/Design</p> <p>The study uses a controlled pre/post design to test an intervention using audit and feedback of healthcare providers to improve their compliance with ABU guidelines. The intervention and the control sites are two VA hospitals. For objective 1 we will review medical records to measure the clinical outcomes of inappropriate screening for and treatment of catheter-associated ABU. For objective 2 we will survey providers' knowledge and attitudes. Three phases of our protocol are proposed: the first 12-month phase will involve observation of the baseline incidence of inappropriate screening for and treatment of ABU at both sites. This surveillance for clinical outcomes will continue at both sites throughout the study. Phase 2 consists of 12 months of individualized audit and feedback at the intervention site and guidelines distribution at both sites. The third phase, also over 12 months, will provide unit-level feedback at the intervention site to assess sustainability. Healthcare providers at the intervention site during phase 2 and at both sites during phase 3 will complete pre/post surveys of awareness and familiarity (knowledge), as well as of acceptance and outcome expectancy (attitudes) regarding the relevant practice guidelines.</p> <p>Discussion</p> <p>Our proposal to bring clinical practice in line with published guidelines has significant potential to decrease overdiagnosis of CAUTI and associated inappropriate antibiotic use. Our study will also provide information about how to maximize effectiveness of audit and feedback to achieve guideline adherence in the inpatient setting.</p> <p>Trial Registration</p> <p><a href="http://www.clinicaltrials.gov/ct2/show/NCT01052545">NCT01052545</a></p
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