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A methodology is presented for the detection of partial blockages in single pipelines by the frequency response method. A steady-oscillatory flow produced by the periodic opening and closing of a valve located at the downstream end is analyzed in the frequency domain by using the transfer matrix method, and a peak pressure frequency response at the valve is developed. The comparison between the peak pressure frequency responses obtained by using the frequency response method and the method of characteristics is satisfactory. If there is a single partial blockage in a piping system, its location may be detected by the pattern and the number of peaks in the peak pressure frequency response. The size of the partial blockage may be determined from the mean peak pressure fluctuation. For two partial blockages, the effective size of the blockages can be determined from the peak pressure frequency response. Knowing the pre- and postdevelopmental frequency responses of a system with an additional partial blockage, the location and size of this additional partial blockage can be detected. CE Database subject headings: Oscillatory flow; Water pipelines: Pipe flow; Frequency response.

Background: Thiazide-type diuretics are associated with an increased incidence of diabetes compared with other antihypertensive medications. In this study, we determined the long-term cardiovascular disease (CVD) consequences of incident diuretic-associated diabetes compared with the effects of incident diabetes associated with calcium channel blocker and angiotensin-converting enzyme inhibitor use.Methods and Results: A total of 22 418 participants from the ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) with baseline diabetes, incident diabetes (7.5% with chlorthalidone, 5.6% with amlodipine, and 4.3% with lisinopril), or no diabetes at 2 years of in-trial follow-up were followed for a mean total of 6.9 years (2.9 years in-trial and 4 additional years posttrial) through the use of national databases. The primary outcome was CVD mortality (death from coronary heart disease [CHD], stroke, heart failure, or other CVD). Among other outcomes were all-cause mortality, non-CVD mortality, and CHD (nonfatal myocardial infarction or fatal CHD). Participants on chlorthalidone with incident diabetes versus no diabetes had consistently lower, nonsignificant risk for CVD mortality (hazard ratio [HR], 1.04; 95% CI, 0.74-1.47), all-cause mortality (HR, 1.04; 95% CI, 0.82-1.30), and non-CVD mortality (HR, 1.05; 95% CI, 0.77-1.42) than participants on amlodipine or lisinopril with incident diabetes (HR range, 1.22-1.53). Participants with incident diabetes had elevated CHD risk compared with those with no diabetes (HR, 1.46; 95% CI, 1.09-1.96), but those on chlorthalidone had significantly lower risk than those on lisinopril (HR, 1.18 versus 2.57; P=0.04 for interaction).Conclusions: The findings suggest that thiazide-related incident diabetes has less adverse long-term CVD impact than incident diabetes that develops while on other antihypertensive medications. [ABSTRACT FROM AUTHOR]

This study examines longitudinal mental health service use patterns of a school-based sample of adolescents. Based on the Center for Epidemiologic Studies Depression Scale scores, a stratified sample of middle-school students was interviewed using the Schedule for Affective Disorders and Schizophrenia for School-Aged Children: cycle one (n = 579; mean age 12.83) and cycle two (n = 490; mean age 18.65). Service use also was assessed by mailed questionnaire: cycle three (n = 330; mean age 20.60). Service use decreased over time. Whites and males received significantly more treatment in the first cycle. In the second cycle, service use by race and gender was equal; in the third cycle, females received more treatment. Those with a psychiatric diagnosis (first cycle, 54%; second cycle, 33%) received treatment in the prior year. Under-treatment of youth with psychiatric diagnoses is a significant problem, with differences in service use by race and gender over time. [ABSTRACT FROM AUTHOR]

Importance: Race and ethnicity have been studied as risk factors in cardiovascular disease. How risk factors, epicardial coronary artery disease, and cardiac events differ between Black and White individuals undergoing noninvasive testing for coronary artery disease is not known., Objective: To assess differences in cardiovascular risk burden, coronary plaque, and major adverse cardiac events between Black and White individuals assigned to receive coronary computed tomography angiography (CCTA) or functional testing for stable chest pain., Design, Setting, and Participants: A nested observational cohort study within the PROMISE trial was conducted at 193 outpatient sites in North America. A total of 1071 non-Hispanic Black (hereafter Black) and 7693 non-Hispanic White (hereafter White) participants with stable chest pain undergoing noninvasive cardiovascular testing were included. This analysis was conducted from February 13, 2015, to November 2, 2021., Main Outcomes and Measures: The primary end point was the composite of death, myocardial infarction, or hospitalization for unstable angina over a median follow-up of 24.4 months., Results: Among 1071 Black individuals (12.2%) (women, 646 [60.3%]; mean [SD] age, 59 [8] years) and 7693 White individuals (87.8%) (women, 4029 [52.4%]; mean [SD] age, 61.1 [8.4] years), Black participants had a higher cardiovascular risk burden (more hypertension and diabetes), yet there was a similarly low major adverse cardiovascular events rate over a median 2-year follow-up (32 [3.0%] vs 243 [3.2%]; P = .84). Sensitivity analyses restricted to the 79.8% (6993 of 8764) individuals with a normal or mildly abnormal noninvasive testing result and the 54.3% (4559 of 8396) not receiving statin therapy yielded similar findings. In comparison of Black and White individuals in the CCTA group (n = 3323), significant coronary stenosis (hazard ratio [HR], 7.21; 95% CI, 1.94-26.76 vs HR, 4.30; 95% CI, 2.62-7.04) and high-risk plaque (HR, 3.47; 95% CI, 1.00-12.06 vs HR, 2.21; 95% CI, 1.37-3.57) were associated with major adverse cardiovascular events in both Black and White patients. However, with respect to epicardial coronary artery disease burden, Black individuals had a less-prevalent coronary artery calcium score greater than 0 (45.1% vs 63.2%; P < .001), coronary stenosis greater than or equal to 50% (32 [8.7%] vs 430 [14.6%]; P = .001), and high-risk plaque (139 [37.6%] vs 1547 [52.4%]; P < .001)., Conclusions and Relevance: The findings of this study suggest that, despite a greater cardiovascular risk burden in Black persons, rates of coronary artery calcium, stenosis, and high-risk plaque observed via CCTA were lower in Black persons than White persons. This result suggests differences in cardiovascular risk burden and coronary plaque in Black and White individuals with stable chest pain.

Background/aims: The value of the Framingham equation in predicting cardiovascular risk in African Americans and patients with chronic kidney disease (CKD) is unclear. The purpose of the study was to evaluate whether the addition of CKD and race to the Framingham equation improves risk stratification in hypertensive patients., Methods: Participants in the ALLHAT were studied. Those randomized to doxazosin, older than 74 years, and those with a history of coronary heart disease were excluded. Two risk stratification models were developed using Cox proportional hazards models in a two-thirds developmental sample. The first model included the traditional Framingham risk factors. The second model included the traditional risk factors plus CKD, defined by estimated glomerular filtration rate categories, and stratification by race (black vs non-black). The primary outcome was a composite of fatal coronary heart disease, nonfatal myocardial infarction, coronary revascularization, and hospitalized angina., Results: There were a total of 19,811 eligible subjects. In the validation cohort, there was no difference in C-statistics between the Framingham equation and the ALLHAT model including CKD and race. This was consistent across subgroups by race and sex and among those with CKD. One exception was among Non-Black women where the C-statistic was higher for the Framingham equation (0.68 vs 0.65, P = .02). In addition, net reclassification improvement was not significant for any subgroup based on race and sex, ranging from -5.5% to 4.4%., Conclusion: The addition of CKD status and stratification by race does not improve risk prediction in high-risk hypertensive patients., (Copyright © 2012 Mosby, Inc. All rights reserved.)

Objectives: This study was designed to determine the usefulness of coronary computed tomography angiography (CTA) in patients with acute chest pain., Background: Triage of chest pain patients in the emergency department remains challenging., Methods: We used an observational cohort study in chest pain patients with normal initial troponin and nonischemic electrocardiogram. A 64-slice coronary CTA was performed before admission to detect coronary plaque and stenosis (>50% luminal narrowing). Results were not disclosed. End points were acute coronary syndrome (ACS) during index hospitalization and major adverse cardiac events during 6-month follow-up., Results: Among 368 patients (mean age 53 +/- 12 years, 61% men), 31 had ACS (8%). By coronary CTA, 50% of these patients were free of coronary artery disease (CAD), 31% had nonobstructive disease, and 19% had inconclusive or positive computed tomography for significant stenosis. Sensitivity and negative predictive value for ACS were 100% (n = 183 of 368; 95% confidence interval [CI]: 98% to 100%) and 100% (95% CI: 89% to 100%), respectively, with the absence of CAD and 77% (95% CI: 59% to 90%) and 98% (n = 300 of 368, 95% CI: 95% to 99%), respectively, with significant stenosis by coronary CTA. Specificity of presence of plaque and stenosis for ACS were 54% (95% CI: 49% to 60%) and 87% (95% CI: 83% to 90%), respectively. Only 1 ACS occurred in the absence of calcified plaque. Both the extent of coronary plaque and presence of stenosis predicted ACS independently and incrementally to Thrombolysis In Myocardial Infarction risk score (area under curve: 0.88, 0.82, vs. 0.63, respectively; all p < 0.0001)., Conclusions: Fifty percent of patients with acute chest pain and low to intermediate likelihood of ACS were free of CAD by computed tomography and had no ACS. Given the large number of such patients, early coronary CTA may significantly improve patient management in the emergency department.

Background: Personalized pharmaceutical marketing to physicians, including the provision of gifts and sponsorship of educational and recreational activities, raises ethical issues. We sought to determine the degree to which physicians regarded common pharmaceutical marketing activities as ethically problematic, and to compare the views of experienced physicians and physicians-in-training., Methods: A questionnaire that included 18 scenarios portraying interactions between physicians and the pharmaceutical industry was distributed to residents and faculty members at a US medical school., Results: Most marketing activities were not thought to pose major ethical problems. Respondents tended to make distinctions about the ethical appropriateness of gifts on the basis of the monetary value and type of gift. Some respondents' views would be in violation of recent professional guidelines that address interactions between physicians and pharmaceutical companies. However, some respondents were troubled by activities that are permitted by professional guidelines. The responses of residents and faculty physicians were similar., Conclusions: Despite the recent publicity about ethical problems in relationships between physicians and the pharmaceutical industry, inexperienced and experienced physicians at a single institution continue to have a rather permissive view about a variety of marketing activities.

Despite a massive expansion of Medicaid and an upswing in the economy, the total number of Americans uninsured in 1993 was 39.7 million, more than at any time since the passage of Medicaid and Medicare in the 1960s. Since 1989, the ranks of the uninsured have swelled by 6.3 million. Millions more would be uninsured if Medicaid enrollment had not risen dramatically, by 10.5 million people since 1989. Loss of health coverage is a growing problem for middle-income families, women, and children, as it has long been for low-income families. Even in Hawaii, whose employer mandate program is often cited as a model of universal coverage, there was a large increase in uninsurance. Nationwide, the sharp upswing in the number of Americans who are uninsured has coincided with government and corporate policies to encourage medical competition and push people into managed care plans. Republican proposals to limit AFDC benefits threaten to further increase uninsurance, particularly among women and children. Only a Canadian-style single-payer reform can assure universal coverage and simultaneously contain costs.

A panel of nine monoclonal antibodies has been produced against a major nuclear protein, B-36, purified from the slime mold Physarum polycephalum. B-36, a 34 kD protein biochemically similar to the major structural proteins of mammalian hnRNP particles, was previously shown to be largely associated with the nucleolus. Eight of the monoclonal antibodies are specific for B-36 protein in Physarum and at least three different epitopes are represented among these eight. Using the monoclonal antibodies B-36 has been shown to be localized exclusively to the nucleolus in actively-growing Physarum cultures. The nucleolar localization of B-36 is dependent on the presence of intact RNA, but not DNA, supporting the hypothesis that B-36 is associated with nucleolar RNA, possibly in some analogous manner to the interaction of the related proteins within heterogeneous nuclear ribonucleoproteins (hnRNP) particles. B-36 is apparently a highly conserved nucleolar protein in eukaryotes as all eight of the monoclonal antibodies specific for B-36 in Physarum are also specific for a 34.5 kD nucleolar protein in rat liver. This indicates that a minimum of three distinct epitopes are conserved in B-36 protein from slime mold to rat.