146 research outputs found
Optimizing the tuning range of the Fermilab Recycler 53MHz RF cavities by exploiting the avoided crossing of the tuner and cavity modes
The electromagnetic eigenmodes of the Fermilab Recycler RF cavities were
simulated with ACE3P running on NERSC's 'Perlmutter' supercomputer in an
attempt to optimize their tuning range to comfortably support slip-stacking. A
theory, based on coupled circuits and avoided crossings, was developed to
explain the origins of the tuning range for tuner-cavity waveguide systems.
This provided a logical, rigorous method to carry out this optimization,
although engineering problems due to high voltages in the tuner and the
operational range of the garnet had to be carefully implemented. It was
shown that the desired goal of 10kHz of tuning was not attainable with the
current cavity specifications. The maximum tuning range obtained was 5.59kHz
for a single tuner with a coaxial line of length 63in. A double tuner cavity
was also studied using the simulation software, although with little
improvement in the tuning range. A promising technique to improve the tuning
range involving the desynchronization of the garnets' magnetic permeabilities
is proposed
An experimental and computational study of tip clearance effects on a transonic turbine stage
This paper describes an experimental and computational investigation into the influence of tip clearance on the blade tip heat load of a high-pressure (HP) turbine stage. Experiments were performed in the Oxford Rotor facility which is a 1½ stage, shroudless, transonic, high pressure turbine. The experiments were conducted at an engine representative Mach number and Reynolds number. Rotating frame instrumentation was used to capture both aerodynamic and heat flux data within the rotor blade row. Two rotor blade tip clearances were tested (1.5% and 1.0% of blade span). The experiments were compared with computational fluid dynamics (CFD) predictions made using a steady Reynolds-averaged Navier–Stokes (RANS) solver. The experiments and computational predictions were in good agreement. The blade tip heat transfer was observed to increase with reduced tip gap in both the CFD and the experiment. The augmentation of tip heat load at smaller clearances was found to be due to the ingestion of high relative total temperature fluid near the casing, generated through casing shear.This work was sponsored by Rolls-Royce plc and the Isle of Man Government.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.ijheatfluidflow.2015.09.00
Testing self-report time-use diaries against objective instruments in real time
This study provides a new test of time-use diary methodology, comparing diaries with a pair of objective criterion measures: wearable cameras and accelerometers. A volunteer sample of respondents (n = 148) completed conventional self-report paper time-use diaries using the standard UK Harmonised European Time Use Study (HETUS) instrument. On the diary day, respondents wore a camera that continuously recorded images of their activities during waking hours (approximately 1,500–2,000 images/day) and also an accelerometer that tracked their physical activity continuously throughout the 24-hour period covered by the diary. Of the initial 148 participants recruited, 131 returned usable diary and camera records, of whom 124 also provided a usable whole-day accelerometer record. The comparison of the diary data with the camera and accelerometer records strongly supports the use of diary methodology at both the aggregate (sample) and individual levels. It provides evidence that time-use data could be used to complement physical activity questionnaires for providing population-level estimates of physical activity. It also implies new opportunities for investigating techniques for calibrating metabolic equivalent of task (MET) attributions to daily activities using large-scale, population-representative time-use diary studies
Participant recruitment and retention in a pilot program to prevent weight gain in low-income overweight and obese mothers
<p>Abstract</p> <p>Background</p> <p>Recruitment and retention are key functions for programs promoting nutrition and other lifestyle behavioral changes in low-income populations. This paper describes strategies for recruitment and retention and presents predictors of early (two-month post intervention) and late (eight-month post intervention) dropout (non retention) and overall retention among young, low-income overweight and obese mothers participating in a community-based randomized pilot trial called <it>Mothers In Motion</it>.</p> <p>Methods</p> <p>Low-income overweight and obese African American and white mothers ages 18 to 34 were recruited from the Special Supplemental Nutrition Program for Women, Infants, and Children in southern Michigan. Participants (n = 129) were randomly assigned to an intervention (n = 64) or control (n = 65) group according to a stratification procedure to equalize representation in two racial groups (African American and white) and three body mass index categories (25.0-29.9 kg/m<sup>2</sup>, 30.0-34.9 kg/m<sup>2</sup>, and 35.0-39.9 kg/m<sup>2</sup>). The 10-week theory-based culturally sensitive intervention focused on healthy eating, physical activity, and stress management messages that were delivered via an interactive DVD and reinforced by five peer-support group teleconferences. Forward stepwise multiple logistic regression was performed to examine whether dietary fat, fruit and vegetable intake behaviors, physical activity, perceived stress, positive and negative affect, depression, and race predicted dropout as data were collected two-month and eight-month after the active intervention phase.</p> <p>Results</p> <p>Trained personnel were successful in recruiting subjects. Increased level of depression was a predictor of early dropout (odds ratio = 1.04; 95% CI = 1.00, 1.08; p = 0.03). Greater stress predicted late dropout (odds ratio = 0.20; 95% CI = 0.00, 0.37; p = 0.01). Dietary fat, fruit, and vegetable intake behaviors, physical activity, positive and negative affect, and race were not associated with either early or late dropout. Less negative affect was a marginal predictor of participant retention (odds ratio = 0.57; 95% CI = 0.31, 1.03; p = 0.06).</p> <p>Conclusion</p> <p>Dropout rates in this study were higher for participants who reported higher levels of depression and stress.</p> <p>Trial registration</p> <p>Current Controlled Trials NCT00944060</p
Working group on cephalopod fisheries and life history (Wgceph; outputs from 2022 meeting)
Rapports Scientifiques du CIEM. Volume 5, nº 1WGCEPH worked on six Terms of Reference. These involved reporting on the status of stocks;
reviewing advances in stock identification, assessment for fisheries management and for the Ma-
rine Strategy Framework Directive (MSFD), including some exploratory stock assessments; re-
viewing impacts of human activities on cephalopods; developing identification guides and rec-
ommendations for fishery data collection; describing the value chain and evaluating market driv-
ers; and reviewing advances in research on environmental tolerance of cephalopods.
ToR A is supported by an annual data call for fishery and survey data. During 2019–2021, com-
pared to 1990–2020, cuttlefish remained the most important cephalopod group in terms of weight
landed along the European North Atlantic coast, while loliginid squid overtook octopus as the
second most important group. Short-finned squid remained the least important group in land-
ings although their relative importance was almost double in 2019–2022 compared to 1992–2020.
Total cephalopod landings have been fairly stable since 1992.
Cuttlefish landings are towards the low end of the recent range, part of a general downward
trend since 2004. Loliginid squid landings in 2019 were close to the maximum seen during the
last 20 years but totals for 2020 and 2021 were lower. Annual ommastrephid squid landings are
more variable than those of the other two groups and close to the maximum seen during 1992–
2021. Octopod landings have generally declined since 2002 but the amount landed in 2021 was
higher than in the previous four years.
Under ToR B we illustrate that the combination of genetic analysis and statolith shape analysis
is a promising method to provide some stock structure information for L. forbsii. With the sum-
mary of cephalopod assessments, we could illustrate that many cephalopod species could al-
ready be included into the MSFD. We further provide material from two reviews in preparation,
covering stock assessment methods and challenges faced for cephalopod fisheries management.
Finally, we summarise trends in abundance indices, noting evidence of recent declines in cuttle-
fish and some octopuses of the genus Eledone.
Under ToR C, we describe progress on the reviews of (i) anthropogenic impacts on cephalopods
and (ii) life history and ecology. In relation to life history, new information on Eledone cirrhosa
from Portugal is included.
Under ToR D we provide an update on identification guides, discuss best practice in fishery data
collection in relation to maturity determination and sampling intensity for fishery monitoring.
Among others, we recommend i) to include the sampling of cephalopods in any fishery that (a)
targets cephalopods, (b) targets both cephalopods and demersal fishes or (c) takes cephalopods
as an important bycatch, ii) Size-distribution sampling, iii) the use of standardized sampling pro-
tocols, iv) an increased sampling effort in cephalopod.
Work under ToR E on value chains and market drivers, in conjunction with the Cephs & Chefs
INTERREG project, has resulted in two papers being submitted. Abstracts of these are in the
report.
Finally, progress under ToR F on environmental tolerance limits of cephalopods and climate en-
velope models is discussed, noting the need to continue this work during the next cycle.info:eu-repo/semantics/publishedVersio
Evaluation of DNA Methylation Episignatures for Diagnosis and Phenotype Correlations in 42 Mendelian Neurodevelopmental Disorders.
Genetic syndromes frequently present with overlapping clinical features and inconclusive or ambiguous genetic findings which can confound accurate diagnosis and clinical management. An expanding number of genetic syndromes have been shown to have unique genomic DNA methylation patterns (called episignatures ). Peripheral blood episignatures can be used for diagnostic testing as well as for the interpretation of ambiguous genetic test results. We present here an approach to episignature mapping in 42 genetic syndromes, which has allowed the identification of 34 robust disease-specific episignatures. We examine emerging patterns of overlap, as well as similarities and hierarchical relationships across these episignatures, to highlight their key features as they are related to genetic heterogeneity, dosage effect, unaffected carrier status, and incomplete penetrance. We demonstrate the necessity of multiclass modeling for accurate genetic variant classification and show how disease classification using a single episignature at a time can sometimes lead to classification errors in closely related episignatures. We demonstrate the utility of this tool in resolving ambiguous clinical cases and identification of previously undiagnosed cases through mass screening of a large cohort of subjects with developmental delays and congenital anomalies. This study more than doubles the number of published syndromes with DNA methylation episignatures and, most significantly, opens new avenues for accurate diagnosis and clinical assessment in individuals affected by these disorders
International genome-wide meta-analysis identifies new primary biliary cirrhosis risk loci and targetable pathogenic pathways.
Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 × 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist
The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study
Background:
Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy.
Methods:
Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored.
Results:
A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays.
Conclusions:
IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients
Effect of SGLT2 inhibitors on stroke and atrial fibrillation in diabetic kidney disease: Results from the CREDENCE trial and meta-analysis
BACKGROUND AND PURPOSE: Chronic kidney disease with reduced estimated glomerular filtration rate or elevated albuminuria increases risk for ischemic and hemorrhagic stroke. This study assessed the effects of sodium glucose cotransporter 2 inhibitors (SGLT2i) on stroke and atrial fibrillation/flutter (AF/AFL) from CREDENCE (Canagliflozin and Renal Events in Diabetes With Established Nephropathy Clinical Evaluation) and a meta-Analysis of large cardiovascular outcome trials (CVOTs) of SGLT2i in type 2 diabetes mellitus. METHODS: CREDENCE randomized 4401 participants with type 2 diabetes mellitus and chronic kidney disease to canagliflozin or placebo. Post hoc, we estimated effects on fatal or nonfatal stroke, stroke subtypes, and intermediate markers of stroke risk including AF/AFL. Stroke and AF/AFL data from 3 other completed large CVOTs and CREDENCE were pooled using random-effects meta-Analysis. RESULTS: In CREDENCE, 142 participants experienced a stroke during follow-up (10.9/1000 patient-years with canagliflozin, 14.2/1000 patient-years with placebo; hazard ratio [HR], 0.77 [95% CI, 0.55-1.08]). Effects by stroke subtypes were: ischemic (HR, 0.88 [95% CI, 0.61-1.28]; n=111), hemorrhagic (HR, 0.50 [95% CI, 0.19-1.32]; n=18), and undetermined (HR, 0.54 [95% CI, 0.20-1.46]; n=17). There was no clear effect on AF/AFL (HR, 0.76 [95% CI, 0.53-1.10]; n=115). The overall effects in the 4 CVOTs combined were: Total stroke (HRpooled, 0.96 [95% CI, 0.82-1.12]), ischemic stroke (HRpooled, 1.01 [95% CI, 0.89-1.14]), hemorrhagic stroke (HRpooled, 0.50 [95% CI, 0.30-0.83]), undetermined stroke (HRpooled, 0.86 [95% CI, 0.49-1.51]), and AF/AFL (HRpooled, 0.81 [95% CI, 0.71-0.93]). There was evidence that SGLT2i effects on total stroke varied by baseline estimated glomerular filtration rate (P=0.01), with protection in the lowest estimated glomerular filtration rate (45 mL/min/1.73 m2]) subgroup (HRpooled, 0.50 [95% CI, 0.31-0.79]). CONCLUSIONS: Although we found no clear effect of SGLT2i on total stroke in CREDENCE or across trials combined, there was some evidence of benefit in preventing hemorrhagic stroke and AF/AFL, as well as total stroke for those with lowest estimated glomerular filtration rate. Future research should focus on confirming these data and exploring potential mechanisms
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