337 research outputs found

    Laser ablation loading of a radiofrequency ion trap

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    The production of ions via laser ablation for the loading of radiofrequency (RF) ion traps is investigated using a nitrogen laser with a maximum pulse energy of 0.17 mJ and a peak intensity of about 250 MW/cm^2. A time-of-flight mass spectrometer is used to measure the ion yield and the distribution of the charge states. Singly charged ions of elements that are presently considered for the use in optical clocks or quantum logic applications could be produced from metallic samples at a rate of the order of magnitude 10^5 ions per pulse. A linear Paul trap was loaded with Th+ ions produced by laser ablation. An overall ion production and trapping efficiency of 10^-7 to 10^-6 was attained. For ions injected individually, a dependence of the capture probability on the phase of the RF field has been predicted. In the experiment this was not observed, presumably because of collective effects within the ablation plume.Comment: submitted to Appl. Phys. B., special issue on ion trappin

    A time-lagged association between the gut microbiome, nestling weight and nestling survival in wild great tits

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    Natal body mass is a key predictor of viability and fitness in many animals. While variation in body mass and therefore juvenile viability may be explained by genetic and environmental factors, emerging evidence points to the gut microbiota as an important factor influencing host health. The gut microbiota is known to change during development, but it remains unclear whether the microbiome predicts fitness, and if it does, at which developmental stage it affects fitness traits. We collected data on two traits associated with fitness in wild nestling great tits Parus major: weight and survival to fledging. We characterised the gut microbiome using 16S rRNA sequencing from nestling faeces and investigated temporal associations between the gut microbiome and fitness traits across development at Day-8 (D8) and Day-15 (D15) post-hatching. We also explored whether particular microbial taxa were ‘indicator species’ that reflected whether nestlings survived or not. There was no link between mass and microbial diversity on D8 or D15. However, we detected a time-lagged relationship where weight at D15 was negatively associated with the microbial diversity at D8, controlling for weight at D8, therefore reflecting relative weight gain over the intervening period. Indicator species analysis revealed that specificity values were high and fidelity values were low, suggesting that indicator taxa were primarily detected within either the survived or not survived groups, but not always detected in birds that either survived or died. Therefore these indicator taxa may be sufficient, but not necessary for determining either survival or mortality, perhaps owing to functional overlap in microbiota. We highlight that measuring microbiome-fitness relationships at just one time point may be misleading, especially early in life. Instead, microbial-host fitness effects may be best investigated longitudinally to detect critical development windows for key microbiota and host traits associated with neonatal weight. Our findings should inform future hypothesis testing to pinpoint which features of the gut microbial community impact on host fitness, and when during development this occurs. Such confirmatory research will shed light on population level processes and could have the potential to support conservation

    Identification of leukocyte surface P2X7 as a biomarker associated with Alzheimer\u27s disease

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    Alzheimer\u27s disease (AD) has shown altered immune responses in the periphery. We studied P2X7 (a proinflammatory receptor and a scavenger receptor) and two integrins, CD11b and CD11c, on the surface of circulating leukocytes and analysed their associations with Aβ-PET, brain atrophy, neuropsychological assessments, and cerebrospinal fluid (CSF) biomarkers. Total 287 age-matched, sex-balanced participants were recruited in a discovery cohort and two validation cohorts through the AIBL study and studied using tri-colour flow cytometry. Our results demonstrated reduced expressions of P2X7, CD11b, and CD11c on leukocytes, particularly monocytes, in Aβ +ve cases compared with Aβ -ve controls. P2X7 and integrin downregulation was observed at pre-clinical stage of AD and stayed low throughout disease course. We further constructed a polygenic risk score (PRS) model based on 12 P2RX7 risk alleles to assess the genetic impact on P2X7 function in AIBL and ADNI cohorts. No significant association was identified between the P2RX7 gene and AD, indicating that P2X7 downregulation in AD is likely caused by environmental changes rather than genetic factors. In conclusion, the downregulation of P2X7 and integrins at pre-clinical stage of AD indicates altered pro-inflammatory responses, phagocytic functions, and migrating capabilities of circulating monocytes in early AD pathogenesis. Our study not only improves our understanding of peripheral immune involvement in early stage of AD but also provides more insights into novel biomarker development, diagnosis, and prognosis of AD

    Developing User‐Friendly Habitat Suitability Tools from Regional Stream Fish Survey Data

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    We developed user‐friendly fish habitat suitability tools (plots) for fishery managers in Michigan; these tools are based on driving habitat variables and fish population estimates for several hundred stream sites throughout the state. We generated contour plots to show patterns in fish biomass for over 60 common species (and for 120 species grouped at the family level) in relation to axes of catchment area and low‐flow yield (90% exceedance flow divided by catchment area) and also in relation to axes of mean and weekly range of July temperatures. The plots showed distinct patterns in fish habitat suitability at each level of biological organization studied and were useful for quantitatively comparing river sites. We demonstrate how these plots can be used to support stream management, and we provide examples pertaining to resource assessment, trout stocking, angling regulations, chemical reclamation of marginal trout streams, indicator species, instream flow protection, and habitat restoration. These straightforward and effective tools are electronically available so that managers can easily access and incorporate them into decision protocols and presentations.Received April 9, 2010; accepted November 8, 2010Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141005/1/nafm0041.pd

    Trends in seasonal influenza vaccine uptake during pregnancy in Western Australia: Implications for midwives

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    Background: Antenatal influenza vaccination is an important public health intervention for preventing serious illness in mothers and newborns, yet uptake remains low. Aim: To evaluate trends in seasonal influenza vaccine coverage and identify determinants for vaccination among pregnant women in Western Australia. Methods: We conducted an annual telephone survey in a random sample of post-partum women who delivered a baby in Western Australia between 2012 and 2014. Women were asked whether influenza vaccination was recommended and/or received during their most recent pregnancy; women were also asked why or why they were not immunised. Findings: Between 2012 and 2014, influenza vaccine coverage increased from 22.9% to 41.4%. Women who reported receiving the majority of their antenatal care from a private obstetrician were significantly more likely to have influenza vaccination recommended to them than those receiving the majority of their care from a public antenatal hospital or general practitioner (p \u3c 0.001). In 2014, the most common reason women reported for accepting influenza vaccination was to protect the baby (92.8%) and the most common reason for being unimmunised was lack of a healthcare provider recommendation (48.5%). Discussion: Antenatal influenza vaccination uptake is increasing, but coverage remains below 50%. A recommendation from the principal care provider is an important predictor of maternal influenza vaccination. Conclusion: Antenatal care providers, including midwives, have a key role in providing appropriate information and evidence-based recommendations to pregnant women to ensure they are making informed decisions. Consistent recommendations from antenatal care providers are critical to improving influenza vaccine coverage in pregnant women

    ACC/AHA Special Report: Clinical Practice Guideline Implementation Strategies: A Summary of Systematic Reviews by the NHLBI Implementation Science Work Group: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

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    BACKGROUND: In 2008, the National Heart, Lung, and Blood Institute convened an Implementation Science Work Group to assess evidence-based strategies for effectively implementing clinical practice guidelines. This was part of a larger effort to update existing clinical practice guidelines on cholesterol, blood pressure, and overweight/obesity. OBJECTIVES: Review evidence from the published implementation science literature and identify effective or promising strategies to enhance the adoption and implementation of clinical practice guidelines. METHODS: This systematic review was conducted on 4 critical questions, each focusing on the adoption and effectiveness of 4 intervention strategies: (1) reminders, (2) educational outreach visits, (3) audit and feedback, and (4) provider incentives. A scoping review of the Rx for Change database of systematic reviews was used to identify promising guideline implementation interventions aimed at providers. Inclusion and exclusion criteria were developed a priori for each question, and the published literature was initially searched up to 2012, and then updated with a supplemental search to 2015. Two independent reviewers screened the returned citations to identify relevant reviews and rated the quality of each included review. RESULTS: Audit and feedback and educational outreach visits were generally effective in improving both process of care (15 of 21 reviews and 12 of 13 reviews, respectively) and clinical outcomes (7 of 12 reviews and 3 of 5 reviews, respectively). Provider incentives showed mixed effectiveness for improving both process of care (3 of 4 reviews) and clinical outcomes (3 reviews equally distributed between generally effective, mixed, and generally ineffective). Reminders showed mixed effectiveness for improving process of care outcomes (27 reviews with 11 mixed and 3 generally ineffective results) and were generally ineffective for clinical outcomes (18 reviews with 6 mixed and 9 generally ineffective results). Educational outreach visits (2 of 2 reviews), reminders (3 of 4 reviews), and provider incentives (1 of 1 review) were generally effective for cost reduction. Educational outreach visits (1 of 1 review) and provider incentives (1 of 1 review) were also generally effective for cost-effectiveness outcomes. Barriers to clinician adoption or adherence to guidelines included time constraints (8 reviews/overviews); limited staffing resources (2 overviews); timing (5 reviews/overviews); clinician skepticism (5 reviews/overviews); clinician knowledge of guidelines (4 reviews/overviews); and higher age of the clinician (1 overview). Facilitating factors included guideline characteristics such as format, resources, and end-user involvement (6 reviews/overviews); involving stakeholders (5 reviews/overviews); leadership support (5 reviews/overviews); scope of implementation (5 reviews/overviews); organizational culture such as multidisciplinary teams and low-baseline adherence (9 reviews/overviews); and electronic guidelines systems (3 reviews). CONCLUSION: The strategies of audit and feedback and educational outreach visits were generally effective in improving both process of care and clinical outcomes. Reminders and provider incentives showed mixed effectiveness, or were generally ineffective. No general conclusion could be reached about cost effectiveness, because of limitations in the evidence. Important gaps exist in the evidence on effectiveness of implementation interventions, especially regarding clinical outcomes, cost effectiveness and contextual issues affecting successful implementation

    A 2x2 randomised factorial SWAT of the use of a pen and small, financial incentive to improve recruitment in a randomised controlled trial of yoga for older adults with multimorbidity [version 2; peer review: 2 approved]

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    Background: Monetary and other incentives may increase recruitment to randomised controlled trials. Methods: 2x2 factorial ‘study within a trial’ of including a pen and/or £5 (GBP) in cash with a postal recruitment pack to increase the number of participants randomised into the host trial (‘Gentle Years Yoga’) for older adults with multimorbidity. Secondary outcomes: return, and time to return, of screening form, and the cost per additional participant randomised. Binary data were analysed using logistic regression and time to return using Cox proportional hazards regression. Results: 818 potential host trial participants were included. Between those sent a pen (n=409) and not sent a pen (n=409), there was no evidence of a difference in the proportion of participants randomised (15 (3.7%) versus 11 (2.7%); OR 1.38, 95% CI 0.63–3.04), in returning a screening form (66 (16.1%) versus 61 (14.9%); OR 1.10, 95% CI 0.75–1.61) nor in time to return the screening form (HR 1.09, 95% CI 0.77–1.55). Between those sent £5 (n=409) and not sent £5 (n=409), there was no evidence of increased randomisation (14 (3.4%) versus 12 (2.9%); OR 1.18, 95% CI 0.54–2.57), but more screening forms were returned (77 (18.8%) versus 50 (12.2%); OR 1.67, 95% CI 1.13–2.45) and there was decreased time to return screening form (HR 1.56, 95% CI 1.09–2.22). No significant interaction between the interventions was observed. The cost per additional participant randomised was £32 and £1000 for the pen and £5, respectively. Conclusion: A small, monetary incentive did not result in more participants being randomised into the host trial but did encourage increased and faster response to the recruitment invitation. Since it is relatively costly, we do not recommend this intervention for use to increase recruitment in this population. Pens were cheaper but did not provide evidence of benefit

    Yoga for older adults with multimorbidity (the Gentle Years Yoga Trial): study protocol for a randomised controlled trial

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    Background Multimorbidity is common in older adults and associated with high levels of illness burden and healthcare expenditure. The evidence base for how to manage older adults with multimorbidity is weak. Yoga might be a useful intervention because it has the potential to improve health-related quality of life, physical functioning, and several medical conditions. The British Wheel of Yoga’s Gentle Years Yoga© (GYY) programme was developed specifically for older adults, including those with chronic medical conditions. Data from a pilot trial suggested feasibility of using GYY in this population, but its effectiveness and cost-effectiveness remain uncertain. Methods This is a multi-site, individually randomised, superiority trial with an embedded process evaluation and an economic analysis of cost-effectiveness. The trial will compare an experimental strategy of offering a 12-week GYY programme against a control strategy of no offer in community-dwelling adults aged 65 or over who have multimorbidity, defined as having two or more chronic conditions from a predefined list. The primary outcome is health-related quality of life measured using the EQ-5D-5L, the primary endpoint being the overall difference over 12 months. Both groups will continue to be able to access their usual care from primary, secondary, community, and social services. Participants, care providers, and yoga teachers will not be blinded to the allocated intervention. Outcome measures are primarily self-reported. The analysis will follow intention-to-treat principles. Discussion This pragmatic randomised controlled trial will demonstrate if the GYY programme is an effective, cost-effective, and viable addition to the management of older adults with multimorbidity. Trial registration ISRCTN ISRCTN13567538. Registered on 18 March 201

    Leukocyte surface biomarkers implicate deficits of innate immunity in sporadic Alzheimer\u27s disease

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    Introduction: Blood-based diagnostics and prognostics in sporadic Alzheimer\u27s disease (AD) are important for identifying at-risk individuals for therapeutic interventions. Methods: In three stages, a total of 34 leukocyte antigens were examined by flow cytometry immunophenotyping. Data were analyzed by logistic regression and receiver operating characteristic (ROC) analyses. Results: We identified leukocyte markers differentially expressed in the patients with AD. Pathway analysis revealed a complex network involving upregulation of complement inhibition and downregulation of cargo receptor activity and Aβ clearance. A proposed panel including four leukocyte markers – CD11c, CD59, CD91, and CD163 – predicts patients’ PET Aβ status with an area under the curve (AUC) of 0.93 (0.88 to 0.97). CD163 was the top performer in preclinical models. These findings have been validated in two independent cohorts. Conclusion: Our finding of changes on peripheral leukocyte surface antigens in AD implicates the deficit in innate immunity. Leukocyte-based biomarkers prove to be both sensitive and practical for AD screening and diagnosis

    Carbonate chemistry covariation with temperature and oxygen in the Salish Sea and California Current Ecosystems: implications for the design of ocean acidification experiments

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    A central goal of ocean acidification (OA) research is to understand the ecological consequences that future changes in ocean chemistry will have on marine ecosystems. To address this uncertainty researchers rely heavily on manipulative experiments where biological responses are evaluated across different pCO2 treatments. In coastal systems, however, contemporary carbonate chemistry variability remains only partially characterized and patterns of covariation with other biologically important variables such as temperature and oxygen are rarely evaluated or incorporated into experimental design. Here, we compiled a large carbonate chemistry data set that consists of measurements from multiple moorings and ship-based sampling campaigns from the Salish Sea and larger California Current Ecosystem (CCE). We evaluated patterns of pCO2 variability and highlight important covariation between pCO2, temperature, and oxygen. We subsequently compared environmental pCO2-temperature measurements with conditions maintained in OA experiments that used organisms from the Salish Sea and CCE. By drawing such comparisons, researchers can gain insight into the ecological relevancy of previously published OA experimental designs, but also identify species or life history stages that may already be influenced by contemporary carbonate chemistry conditions. We illustrate the implications that covariation among environmental variables can have for the interpretation of OA experimental results and suggest an approach for developing experimental designs with pCO2 levels that better reflect OA hypotheses while simultaneously recognizing natural covariation with other biologically relevant variables
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