143 research outputs found
Thrust vector control study for large /260 inch/ rocket motor applications
Design concepts of thrust vector control for large rocket motor application
Science-based restoration monitoring of coastal habitats, Volume One: A framework for monitoring plans under the Estuaries and Clean Waters Act of 2000 (Public Law 160-457)
Executive Summary:
The Estuary Restoration Act of 2000 (ERA), Title I of the Estuaries and Clean Waters Act of 2000, was created to promote the restoration of habitats along the coast of the United States (including the US protectorates and the Great Lakes). The NOAA National Centers for Coastal Ocean Science was charged with the development of a guidance manual for monitoring plans under this Act.
This guidance manual, titled Science-Based Restoration Monitoring of Coastal Habitats, is written in two volumes. It provides technical assistance, outlines necessary steps, and provides useful tools for the development and implementation of sound scientific monitoring of coastal restoration efforts. In addition, this manual offers a means to detect early warnings that the restoration is on track or not, to gauge how well a restoration site is functioning, to coordinate projects and efforts for consistent and successful restoration, and to evaluate the ecological health of specific coastal habitats both before and after project completion (Galatowitsch et al. 1998).
The following habitats have been selected for discussion in this manual: water column, rock bottom, coral reefs, oyster reefs, soft bottom, kelp and other macroalgae, rocky shoreline, soft shoreline, submerged aquatic vegetation, marshes, mangrove swamps, deepwater swamps, and riverine forests. The classification of habitats used in this document is generally based on that of Cowardin et al. (1979) in their Classification of Wetlands and Deepwater Habitats of the United States, as called for in the ERA Estuary Habitat Restoration Strategy.
This manual is not intended to be a restoration monitoring “cookbook” that provides templates of monitoring plans for specific habitats. The interdependence of a large number of site-specific factors causes habitat types to vary in physical and biological structure within and between regions and geographic locations (Kusler and Kentula 1990). Monitoring approaches used should be tailored to these differences. However, even with the diversity of habitats that may need to be restored and the extreme geographic range across which these habitats occur, there are consistent principles and approaches that form a common basis for effective monitoring.
Volume One, titled A Framework for Monitoring Plans under the Estuaries and Clean Waters Act of 2000, begins with definitions and background information. Topics such as restoration, restoration monitoring, estuaries, and the role of socioeconomics in restoration are discussed. In addition, the habitats selected for discussion in this manual are briefly described. (PDF contains 116 pages
Six-minute walk distance after coronary artery bypass grafting compared with medical therapy in ischaemic cardiomyopathy
Background: In patients with ischaemic left ventricular dysfunction, coronary artery bypass surgery (CABG) may decrease mortality, but it is not known whether CABG improves functional capacity.
Objective: To determine whether CABG compared with medical therapy alone (MED) increases 6 min walk distance in patients with ischaemic left ventricular dysfunction and coronary artery disease amenable to revascularisation.
Methods: The Surgical Treatment in Ischemic Heart disease trial randomised 1212 patients with ischaemic left ventricular dysfunction to CABG or MED. A 6 min walk distance test was performed both at baseline and at least one follow-up assessment at 4, 12, 24 and/or 36 months in 409 patients randomised to CABG and 466 to MED. Change in 6 min walk distance between baseline and follow-up were compared by treatment allocation.
Results: 6 min walk distance at baseline for CABG was mean 340±117 m and for MED 339±118 m. Change in walk distance from baseline was similar for CABG and MED groups at 4 months (mean +38 vs +28 m), 12 months (+47 vs +36 m), 24 months (+31 vs +34 m) and 36 months (−7 vs +7 m), P>0.10 for all. Change in walk distance between CABG and MED groups over all assessments was also similar after adjusting for covariates and imputation for missing values (+8 m, 95% CI −7 to 23 m, P=0.29). Results were consistent for subgroups defined by angina, New York Heart Association class ≥3, left ventricular ejection fraction, baseline walk distance and geographic region.
Conclusion: In patients with ischaemic left ventricular dysfunction CABG compared with MED alone is known to reduce mortality but is unlikely to result in a clinically significant improvement in functional capacity
Effect of Oral Iron Repletion on Exercise Capacity in Patients With Heart Failure With Reduced Ejection Fraction and Iron Deficiency: The IRONOUT HF Randomized Clinical Trial.
Importance: Iron deficiency is present in approximately 50% of patients with heart failure with reduced left ventricular ejection fraction (HFrEF) and is an independent predictor of reduced functional capacity and mortality. However, the efficacy of inexpensive readily available oral iron supplementation in heart failure is unknown.
Objective: To test whether therapy with oral iron improves peak exercise capacity in patients with HFrEF and iron deficiency.
Design, Setting, and Participants: Phase 2, double-blind, placebo-controlled randomized clinical trial of patients with HFrEF (
Interventions: Oral iron polysaccharide (n = 111) or placebo (n = 114), 150 mg twice daily for 16 weeks.
Main Outcomes and Measures: The primary end point was a change in peak oxygen uptake (V̇o2) from baseline to 16 weeks. Secondary end points were change in 6-minute walk distance, plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, and health status as assessed by Kansas City Cardiomyopathy Questionnaire (KCCQ, range 0-100, higher scores reflect better quality of life).
Results: Among 225 randomized participants (median age, 63 years; 36% women) 203 completed the study. The median baseline peak V̇o2 was 1196 mL/min (interquartile range [IQR], 887-1448 mL/min) in the oral iron group and 1167 mL/min (IQR, 887-1449 mL/min) in the placebo group. The primary end point, change in peak V̇o2 at 16 weeks, did not significantly differ between the oral iron and placebo groups (+23 mL/min vs -2 mL/min; difference, 21 mL/min [95% CI, -34 to +76 mL/min]; P = .46). Similarly, at 16 weeks, there were no significant differences between treatment groups in changes in 6-minute walk distance (-13 m; 95% CI, -32 to 6 m), NT-proBNP levels (159; 95% CI, -280 to 599 pg/mL), or KCCQ score (1; 95% CI, -2.4 to 4.4), all P \u3e .05.
Conclusions and Relevance: Among participants with HFrEF with iron deficiency, high-dose oral iron did not improve exercise capacity over 16 weeks. These results do not support use of oral iron supplementation in patients with HFrEF.
Trial Registration: clinicaltrials.gov Identifier: NCT02188784
Sudden cardiac death in patients with ischemic heart failure undergoing coronary artery bypass grafting results from the STICH randomized clinical trial (Surgical Treatment for Ischemic Heart Failure)
Background—The risk of sudden cardiac death (SCD) in patients with heart failure following CABG has not been examined in a contemporary clinical trial of surgical revascularization. This analysis describes the incidence, timing and clinical predictors of SCD after CABG.
Methods—Patients enrolled in the Surgical Treatment of Ischemic Heart Failure (STICH) trial who underwent CABG with or without surgical ventricular reconstruction (SVR) were included. We excluded patients with prior ICD and those randomized only to medical therapy. The primary outcome was SCD as adjudicated by a blinded committee. A Cox model was used to examine and identify predictors of SCD. The Fine and Gray method was used to estimate the incidence of SCD accounting for the competing risk of other deaths.
Results—Over a median follow-up of 46 months, 113 patients of 1411 patients who received CABG without (n = 934) or with SVR (n = 477) had SCD; 311 died of other causes. The mean LVEF at enrollment was 28±9%. The 5-year cumulative incidence of SCD was 8.5%. Patients who had SCD and those who did not die were younger and had fewer comorbid conditions than those who died for reasons other than SCD. In the first 30 days after CABG, SCD (n=5) accounted for 7% of all deaths. The numerically greatest monthly rate of SCD was in the 31-90 day time period. In a multivariable analysis including baseline demographics, risk factors, coronary anatomy and LV function, ESVI and BNP were most strongly associated with SCD.
Conclusions—The monthly risk of SCD shortly after CABG among patients with a low LVEF is highest between the first and third month, suggesting that risk stratification for SCD should occur early in the postoperative period, particularly in patients with increased preoperative ESVI and/or BNP
Coronary-artery bypass surgery in patients with ischemic cardiomyopathy
BACKGROUND
The survival benefit of a strategy of coronary-artery bypass grafting (CABG) added to
guideline-directed medical therapy, as compared with medical therapy alone, in patients
with coronary artery disease, heart failure, and severe left ventricular systolic
dysfunction remains unclear.
METHODS
From July 2002 to May 2007, a total of 1212 patients with an ejection fraction of 35%
or less and coronary artery disease amenable to CABG were randomly assigned to
undergo CABG plus medical therapy (CABG group, 610 patients) or medical therapy
alone (medical-therapy group, 602 patients). The primary outcome was death from any
cause. Major secondary outcomes included death from cardiovascular causes and death
from any cause or hospitalization for cardiovascular causes. The median duration of
follow-up, including the current extended-follow-up study, was 9.8 years.
RESULTS
A primary outcome event occurred in 359 patients (58.9%) in the CABG group and in
398 patients (66.1%) in the medical-therapy group (hazard ratio with CABG vs. medical
therapy, 0.84; 95% confidence interval [CI], 0.73 to 0.97; P=0.02 by log-rank test). A
total of 247 patients (40.5%) in the CABG group and 297 patients (49.3%) in the
medical-therapy group died from cardiovascular causes (hazard ratio, 0.79; 95% CI,
0.66 to 0.93; P=0.006 by log-rank test). Death from any cause or hospitalization for
cardiovascular causes occurred in 467 patients (76.6%) in the CABG group and in 524
patients (87.0%) in the medical-therapy group (hazard ratio, 0.72; 95% CI, 0.64 to 0.82;
P<0.001 by log-rank test).
CONCLUSIONS
In a cohort of patients with ischemic cardiomyopathy, the rates of death from any
cause, death from cardiovascular causes, and death from any cause or hospitalization
for cardiovascular causes were significantly lower over 10 years among patients who
underwent CABG in addition to receiving medical therapy than among those who received
medical therapy alone. (Funded by the National Institutes of Health; STICH [and
STICHES] ClinicalTrials.gov number, NCT00023595.
Ethnic Minorities and their Health Needs: Crisis of Perception and Behaviours
There is considerable evidence to suggest that racial and ethnic disparities exist in the provision of emergency and wider healthcare. The importance of collecting patient ethnic data has received attention in literature across the world and eliminating ethnic and racial health equalities is one of the primary aims of healthcare providers internationally. The poor health status of certain racial and ethnic groups has been well documented. The improvement of racial and ethnic disparities in healthcare is at the forefront of many public health agendas. This article addresses important policy, practice, and cultural issues confronted by the pre-hospital emergency care setup. This aspect of care plays a unique role in the healthcare safety net in providing a service to a very diverse population, including members of ethnic and racial minorities. Competent decision making by the emergency care practitioners requires patient-specific information and the health provider's prior medical knowledge and clinical training. The article reviews the current ethnicity trends in the UK along with international evidence linking ethnicity and health inequalities. The study argues that serious difficulties will arise between the health provider and the patient if they come from different backgrounds and therefore experience difficulties in cross-cultural communication. This adversely impacts on the quality of diagnostic and clinical decision making for minority patients. The article offers few strategies to address health inequalities in emergency care and concludes by arguing that much more needs to be done to ensure that we are hearing the voices of more diverse groups, groups who are often excluded from engagement through barriers such as language or mobility difficulties
Coronary bypass surgery with or without surgical ventricular reconstruction
Coronary bypass surgery with or without surgical ventricular reconstruction.
Jones RH, Velazquez EJ, Michler RE, Sopko G, Oh JK, O'Connor CM, Hill JA, Menicanti L, Sadowski Z, Desvigne-Nickens P, Rouleau JL, Lee KL; STICH Hypothesis 2 Investigators.
Collaborators (379)Bochenek A, Krejca M, Trusz-Gluza M, Wita K, Zembala M, Przybylski R, Kukulski T, Cherniavsky A, Marchenko A, Romanov A, Wos S, Deja M, Golba K, Kot J, Rao V, Iwanochko M, Renton J, Hemeon S, Rogowski J, Rynkiewicz A, Betlejewski P, Sun B, Crestanello J, Binkley P, Chang J, Ferrazzi P, Gavazzi A, Senni M, Sadowski J, Kapelak B, Sobczyk D, Wrobel K, Pirk J, Jandova R, Velazquez E, Smith P, Milano C, Adams P, Menicanti L, Di Donato M, Castelvecchio S, Dagenais F, Dussault G, Dupree C, Sheridan B, Schuler C, Yii M, Prior D, Mack J, Racine N, Bouchard D, Ducharme A, Lavoignat J, Maurer G, Grimm M, Lang I, Adlbrecht C, Religa Z, Biederman A, Szwed H, Sadowski Z, Rajda M, Ali I, Howlett J, MacFarlane M, Siepe M, Beyersdorf F, Cuerten C, Wiechowski S, Mokrzycki K, Hill J, Beaver T, Olitsky D, Bernstein V, Janusz M, O'Neill V, Grayburn P, Hebeler R, Hamman B, Aston S, Gradinac S, Vukovic M, Djokovic L, Benetis R, Jankauskiene L, Friedrich I, Buerke M, Paraforos A, Quaini E, Cirillo M, Chua L, Lim C, Kwok B, Kong S, Stefanelli G, Labia C, Bergh C, Gustafsson C, Daly R, Rodeheffer R, Nelson S, Maitland A, Isaac D, Holland M, Di Benedetto G, Attisano T, Sievers H, Schunkert H, Stierle U, Haddad H, Hendry P, Donaldson J, Birjiniuk V, Harrington M, Nawarawong W, Woragidpunpol S, Kuanprasert S, Mekara W, Konda S, Neva C, Hathaway W, Groh M, Blakely J, Lamy A, Demers C, Rizzo T, Drazner M, DiMaio J, Joy J, Benedik J, Marketa K, Beghi C, De Blasi M, Helou J, Dallaire S, Kron I, Kern J, Bergin J, Phillips J, Aldea G, Verrier E, Harrison L, Piegas L, Paulista P, Farsky P, Veiga-Kantorowitz C, Philippides G, Shemin R, Thompson J, White H, Alison P, Stewart R, Clapham T, Rich J, Herre J, Pine L, Kalil R, Nesralla I, Santos M, Pereira de Moraes M, Michler R, Swayze R, Arnold M, McKenzie N, Smith J, Nicolau J, Oliveira S, Stolf N, Ferraz M, Filgueira J, Batlle C, Rocha A, Gurgel Camara A, Huynh T, Cecere R, Finkenbine S, St-Jacques B, Ilton M, Wittstein I, Conte J, Breton E, Panza J, Boyce S, McNulty M, Starnes V, Lopez B, Biederman R, Magovern J, Dean D, Grant S, Hammon J, Wells G, De Pasquale C, Knight J, Healy H, Maia L, Souza A, McRae R, Pierson M, Gullestad L, Sorensen G, Murphy E, Ravichandran P, Avalos K, Horowitz J, Owen E, Ascheim D, Naka Y, Yushak M, Gerometta P, Arena V, Borghini E, Johnsson P, Ekmehag B, Engels K, Rosenblum W, Swayze R, Amanullah A, Krzeminska-Pakula M, Drozdz J, Larbalestier R, Wang X, Busmann C, Horkay F, Szekely L, Keltai M, Hetzer R, Knosalla C, Nienkarken T, Chiariello L, Nardi P, Arom K, Ruengsakulrach P, Hayward C, Jansz P, Stuart S, Oto O, Sariomanoglu O, Dignan R, French J, Gonzalez M, Edes I, Szathmarine V, Yakub M, Sarip S, Alotti N, Lupkovics G, Smedira N, Pryce J, Cokkinos D, Palatianos G, Kremastinos D, Stewart R, Rinkes L, Esrig B, Baptiste M, Booth D, Ramaiah C, Ferraris V, Menon S, Martin L, Couper G, Rosborough D, Vanhaecke J, Strijckmans A, Carson P, Dupree C, Miller A, Pina I, Selzman C, Wertheimer J, Goldstein S, Cohn F, Hlatky M, Kennedy K, Rankin S, Robbins R, Zaret B, Rouleau J, Desvigne-Nickens P, Jones R, Lee K, Michler R, O'Connor C, Oh J, Rankin G, Velazquez E, Hill J, Beyersdorf F, Bonow R, Desvigne-Nickens P, Jones R, Lee K, Oh J, Panza J, Rouleau J, Sadowski Z, Velazquez E, White H, Jones R, Velazquez E, O'Connor C, Rankin G, Sellers M, Sparrow-Parker B, McCormick A, Albright J, Dandridge R, Rittenhouse L, Wagstaff D, Wakeley N, Burns S, Williams M, Bailey D, Parrish L, Daniels H, Grissom G, Medlin K, Lee K, She L, McDaniel A, Lokhnygina Y, Greene D, Moore V, Pohost G, Agarwal S, Apte P, Bahukha P, Chow M, Chu X, Doyle M, Forder J, Ocon M, Reddy V, Santos N, Tripathi R, Varadarajan P, Oh J, Blahnik F, Bruce C, Lin G, Manahan B, Miller D, Miller F, Pellikka P, Springer R, Welper J, Wiste H, Mark D, Anstrom K, Baloch K, Burnette A, Clapp-Channing N, Cowper P, Davidson-Ray N, Drew L, Harding T, Hunt V, Knight D, Patterson A, Redick T, Sanderford B, Feldman A, Bristow M, Chan T, Diamond M, Maisel A, Mann D, McNamara D, Bonow R, Berman D, Helmer D, Holly T, Leonard S, Woods M, Panza J, McNulty M, Grayburn P, Aston S.
SourceDuke Clinical Research Institute, Duke University Medical Center, Durham, NC 27710, USA. [email protected]
Abstract
BACKGROUND: Surgical ventricular reconstruction is a specific procedure designed to reduce left ventricular volume in patients with heart failure caused by coronary artery disease. We conducted a trial to address the question of whether surgical ventricular reconstruction added to coronary-artery bypass grafting (CABG) would decrease the rate of death or hospitalization for cardiac causes, as compared with CABG alone.
METHODS: Between September 2002 and January 2006, a total of 1000 patients with an ejection fraction of 35% or less, coronary artery disease that was amenable to CABG, and dominant anterior left ventricular dysfunction that was amenable to surgical ventricular reconstruction were randomly assigned to undergo either CABG alone (499 patients) or CABG with surgical ventricular reconstruction (501 patients). The primary outcome was a composite of death from any cause and hospitalization for cardiac causes. The median follow-up was 48 months.
RESULTS: Surgical ventricular reconstruction reduced the end-systolic volume index by 19%, as compared with a reduction of 6% with CABG alone. Cardiac symptoms and exercise tolerance improved from baseline to a similar degree in the two study groups. However, no significant difference was observed in the primary outcome, which occurred in 292 patients (59%) who were assigned to undergo CABG alone and in 289 patients (58%) who were assigned to undergo CABG with surgical ventricular reconstruction (hazard ratio for the combined approach, 0.99; 95% confidence interval, 0.84 to 1.17; P=0.90).
CONCLUSIONS: Adding surgical ventricular reconstruction to CABG reduced the left ventricular volume, as compared with CABG alone. However, this anatomical change was not associated with a greater improvement in symptoms or exercise tolerance or with a reduction in the rate of death or hospitalization for cardiac causes. (ClinicalTrials.gov number, NCT00023595.
GenTAC registry report: Gender differences among individuals with genetically triggered thoracic aortic aneurysm and dissection
Previous data suggest women are at increased risk of death from aortic dissection. Therefore, we analyzed data from the GenTAC registry, the NIH‐sponsored program that collects information about individuals with genetically triggered thoracic aortic aneurysms and cardiovascular conditions. We performed cross‐sectional analyses in adults with Marfan syndrome (MFS), familial thoracic aortic aneurysm or dissection (FTAAD), bicuspid aortic valve (BAV) with thoracic aortic aneurysm or dissection, and subjects under 50 years of age with thoracic aortic aneurysm or dissection (TAAD <50 years). Women comprised 32% of 1,449 subjects and were 21% of subjects with BAV, 34% with FTAAD, 22% with TAAD <50 years, and 47% with MFS. Thoracic aortic dissections occurred with equal gender frequency yet women with BAV had more extensive dissections. Aortic size was smaller in women but was similar after controlling for BSA. Age at operation for aortic valve dysfunction, aneurysm or dissection did not differ by gender. Multivariate analysis (adjusting for age, BSA, hypertension, study site, diabetes, and subgroup diagnoses) showed that women had fewer total aortic surgeries (OR = 0.65, P < 0.01) and were less likely to receive angiotensin converting enzyme inhibitors (ACEi; OR = 0.68, P < 0.05). As in BAV, other genetically triggered aortic diseases such as FTAAD and TAAD <50 are more common in males. In women, decreased prevalence of aortic operations and less treatment with ACEi may be due to their smaller absolute aortic diameters. Longitudinal studies are needed to determine if women are at higher risk for adverse events. © 2013 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97193/1/35836_ftp.pd
Visible and Invisible Trends in Black Men's Health: Pitfalls and Promises for Addressing Racial, Ethnic, and Gender Inequities in Health
Over the past two decades, there has been growing interest in improving black men's health and the health disparities affecting them. Yet, the health of black men consistently ranks lowest across nearly all groups in the United States. Evidence on the health and social causes of morbidity and mortality among black men has been narrowly concentrated on public health problems (e.g., violence, prostate cancer, and HIV/AIDS) and determinants of health (e.g., education and male gender socialization). This limited focus omits age-specific leading causes of death and other social determinants of health, such as discrimination, segregation, access to health care, employment, and income. This review discusses the leading causes of death for black men and the associated risk factors, as well as identifies gaps in the literature and presents a racialized and gendered framework to guide efforts to address the persistent inequities in health affecting black men
- …