In this work, we present a compact laser-produced plasma source of X-rays, developed and characterized for application in soft X-ray contact microscopy (SXCM). The source is based on a double stream ...gas puff target, irradiated with a commercially available Nd:YAG laser, delivering pulses with energy up to 740mJ and 4ns pulse duration at 10Hz repetition rate. The target is formed by pulsed injection of a stream of high-Z gas (argon) into a cloud of low Z-gas (helium) by using an electromagnetic valve with a double nozzle setup. The source is designed to irradiate specimens, both in vacuum and in helium atmosphere with nanosecond pulses of soft X-rays in the “water-window” spectral range. The source is capable of delivering a photon fluence of about 1.09×103photon/μm2/pulse at a sample placed in vacuum at a distance of about 20mm downstream the source. It can also deliver a photon fluence of about 9.31×102photons/µm2/pulse at a sample placed in a helium atmosphere at the same position. The source design and results of the characterization measurements as well as the optimization of the source are presented and discussed. The source was successfully applied in the preliminary experiments on soft X-ray contact microscopy and images of microstructures and biological specimens with ∼80nm half-pitch spatial resolution, obtained in helium atmosphere, are presented.
BACKGROUND AND PURPOSE—This American Heart Association (AHA) scientific statement provides a comprehensive overview of current evidence on the burden cardiovascular disease (CVD) among Hispanics in ...the United States. Hispanics are the largest minority ethnic group in the United States, and their health is vital to the public health of the nation and to achieving the AHA’s 2020 goals. This statement describes the CVD epidemiology and related personal beliefs and the social and health issues of US Hispanics, and it identifies potential prevention and treatment opportunities. The intended audience for this statement includes healthcare professionals, researchers, and policy makers.
METHODS—Writing group members were nominated by the AHA’s Manuscript Oversight Committee and represent a broad range of expertise in relation to Hispanic individuals and CVD. The writers used a general framework outlined by the committee chair to produce a comprehensive literature review that summarizes existing evidence, indicate gaps in current knowledge, and formulate recommendations. Only English-language studies were reviewed, with PubMed/MEDLINE as our primary resource, as well as the Cochrane Library Reviews, Centers for Disease Control and Prevention, and the US Census data as secondary resources. Inductive methods and descriptive studies that focused on CVD outcomes incidence, prevalence, treatment response, and risks were included. Because of the wide scope of these topics, members of the writing committee were responsible for drafting individual sections selected by the chair of the writing committee, and the group chair assembled the complete statement. The conclusions of this statement are the views of the authors and do not necessarily represent the official view of the AHA. All members of the writing group had the opportunity to comment on the initial drafts and approved the final version of this document. The manuscript underwent extensive AHA internal peer review before consideration and approval by the AHA Science Advisory and Coordinating Committee.
RESULTS—This statement documents the status of knowledge regarding CVD among Hispanics and the sociocultural issues that impact all subgroups of Hispanics with regard to cardiovascular health. In this review, whenever possible, we identify the specific Hispanic subgroups examined to avoid generalizations. We identify specific areas for which current evidence was less robust, as well as inconsistencies and evidence gaps that inform the need for further rigorous and interdisciplinary approaches to increase our understanding of the US Hispanic population and its potential impact on the public health and cardiovascular health of the total US population. We provide recommendations specific to the 9 domains outlined by the chair to support the development of these culturally tailored and targeted approaches.
CONCLUSIONS—Healthcare professionals and researchers need to consider the impact of culture and ethnicity on health behavior and ultimately health outcomes. There is a need to tailor and develop culturally relevant strategies to engage Hispanics in cardiovascular health promotion and cultivate a larger workforce of healthcare providers, researchers, and allies with the focused goal of improving cardiovascular health and reducing CVD among the US Hispanic population.
PURPOSE—The aim of this statement is to summarize data on stroke risk factors that are unique to and more common in women than men and to expand on the data provided in prior stroke guidelines and ...cardiovascular prevention guidelines for women. This guideline focuses on the risk factors unique to women, such as reproductive factors, and those that are more common in women, including migraine with aura, obesity, metabolic syndrome, and atrial fibrillation.
METHODS—Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association (AHA) Stroke Council’s Scientific Statement Oversight Committee and the AHA’s Manuscript Oversight Committee. The panel reviewed relevant articles on adults using computerized searches of the medical literature through May 15, 2013. The evidence is organized within the context of the AHA framework and is classified according to the joint AHA/American College of Cardiology and supplementary AHA Stroke Council methods of classifying the level of certainty and the class and level of evidence. The document underwent extensive AHA internal peer review, Stroke Council Leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the AHA Science Advisory and Coordinating Committee.
RESULTS—We provide current evidence, research gaps, and recommendations on risk of stroke related to preeclampsia, oral contraceptives, menopause, and hormone replacement, as well as those risk factors more common in women, such as obesity/metabolic syndrome, atrial fibrillation, and migraine with aura.
CONCLUSIONS—To more accurately reflect the risk of stroke in women across the lifespan, as well as the clear gaps in current risk scores, we believe a female-specific stroke risk score is warranted.
Objectives This study sought to assess the effect of the addition of coronary artery bypass grafting (CABG) to medical therapy on mode of death in heart failure. Background Although CABG therapy is ...widely used in ischemic cardiomyopathy patients, there are no prospective clinical trial data on mode of death. Methods The STICH (Surgical Treatment for Ischemic Heart Failure ) trial compared the strategy of CABG plus medical therapy to medical therapy alone in 1,212 ischemic cardiomyopathy patients with reduced ejection fraction. A clinical events committee adjudicated deaths using pre-specified definitions for mode of death. Results In the STICH trial, there were 462 deaths over a median follow-up of 56 months. The addition of CABG therapy tended to reduce cardiovascular deaths (hazard ratio HR: 0.83; 95% confidence interval CI: 0.68 to 1.03; p = 0.09) and significantly reduced the most common modes of death: sudden death (HR: 0.73; 95% CI: 0.54 to 0.99; p = 0.041) and fatal pump failure events (HR: 0.64; 95% CI: 0.41 to 1.00; p = 0.05). Time-dependent estimates indicate that the protective effect of CABG principally occurred after 24 months in both categories. Deaths post-cardiovascular procedures were increased in CABG patients (HR: 3.11; 95% CI: 1.47 to 6.60), but fatal myocardial infarction deaths were lower (HR: 0.07; 95% CI: 0.01 to 0.57). Noncardiovascular deaths were infrequent and did not differ between groups. Conclusions In the STICH trial, the addition of CABG to medical therapy reduced the most common modes of death: sudden death and fatal pump failure events. The beneficial effects were principally seen after 2 years. Post-procedure deaths were increased in patients randomized to CABG, whereas myocardial infarction deaths were decreased.
CONTEXT Findings from previous studies of the effects of exercise training on patient-reported health status have been inconsistent. OBJECTIVE To test the effects of exercise training on health ...status among patients with heart failure. DESIGN, SETTING, AND PATIENTS Multicenter, randomized controlled trial among 2331 medically stable outpatients with heart failure with left ventricular ejection fraction of 35% or less. Patients were randomized from April 2003 through February 2007. INTERVENTIONS Usual care plus aerobic exercise training (n = 1172), consisting of 36 supervised sessions followed by home-based training, vs usual care alone (n = 1159). Randomization was stratified by heart failure etiology, which was a covariate in all models. MAIN OUTCOME MEASURES Kansas City Cardiomyopathy Questionnaire (KCCQ) overall summary scale and key subscales at baseline, every 3 months for 12 months, and annually thereafter for up to 4 years. The KCCQ is scored from 0 to 100 with higher scores corresponding to better health status. Treatment group effects were estimated using linear mixed models according to the intention-to-treat principle. RESULTS Median follow-up was 2.5 years. At 3 months, usual care plus exercise training led to greater improvement in the KCCQ overall summary score (mean, 5.21; 95% confidence interval, 4.42 to 6.00) compared with usual care alone (3.28; 95% confidence interval, 2.48 to 4.09). The additional 1.93-point increase (95% confidence interval, 0.84 to 3.01) in the exercise training group was statistically significant (P < .001). After 3 months, there were no further significant changes in KCCQ score for either group (P = .85 for the difference between slopes), resulting in a sustained, greater improvement overall for the exercise group (P < .001). Results were similar on the KCCQ subscales, and no subgroup interactions were detected. CONCLUSIONS Exercise training conferred modest but statistically significant improvements in self-reported health status compared with usual care without training. Improvements occurred early and persisted over time. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00047437.
Type 2 diabetes mellitus is a risk factor for incident heart failure and increases the risk of morbidity and mortality in patients with established disease. Secular trends in the prevalence of ...diabetes mellitus and heart failure forecast a growing burden of disease and underscore the need for effective therapeutic strategies. Recent clinical trials have demonstrated the shared pathophysiology between diabetes mellitus and heart failure, the synergistic effect of managing both conditions, and the potential for diabetes mellitus therapies to modulate the risk of heart failure outcomes. This scientific statement on diabetes mellitus and heart failure summarizes the epidemiology, pathophysiology, and impact of diabetes mellitus and its control on outcomes in heart failure; reviews the approach to pharmacological therapy and lifestyle modification in patients with diabetes mellitus and heart failure; highlights the value of multidisciplinary interventions to improve clinical outcomes in this population; and outlines priorities for future research.
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