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Sample records for 24-hour systolic bp

  1. 24-hour central aortic systolic pressure and 24-hour central pulse pressure are related to diabetic complications in type 1 diabetes – a cross-sectional study

    PubMed Central

    2013-01-01

    Background Non-invasive measurements of 24 hour ambulatory central aortic systolic pressure (24 h-CASP) and central pulse pressure (24 h-CPP) are now feasible. We evaluate the relationship between 24 h central blood pressure and diabetes-related complications in patients with type 1 diabetes. Methods The study was cross-sectional, including 715 subjects: 86 controls (C), 69 patients with short diabetes duration (< 10 years), normoalbuminuria (< 30 mg/24 h) without receiving antihypertensive treatment (SN), 211 with longstanding diabetes (≥ 10 years) and normoalbuminuria (LN), 163 with microalbuminuria (30-299 mg/24 h) (Mi) and 186 with macroalbuminuria (> 300 mg/24 h) (Ma). 24 h-CASP and 24 h-CPP was measured using a tonometric wrist-watch-like device (BPro, HealthStats, Singapore) and derived using N-point moving average. Results In C, SN, LN, Mi and Ma mean ± SD 24 h-CASP was: 114 ± 17, 115 ± 13, 121 ± 13, 119 ± 16 and 121 ± 13 mmHg (p < 0.001); and 24 h-CPP: 38 ± 8, 38 ± 7, 44 ± 10, 46 ± 11 and 46 ± 11 mmHg, (p < 0.001). Following rigorous adjustment (24 h mean arterial pressure and conventional risk factors), 24 h-CASP and 24 h-CPP increased with diabetes, albuminuria degree, previous cardiovascular disease (CVD), retinopathy and autonomic dysfunction (p ≤ 0.031). Odds ratios per 1 standard deviation increase in 24 h-CASP, 24 h-CPP and 24 h systolic blood pressure (24 h-SBP) were for CVD: 3.19 (1.68-6.05), 1.43 (1.01-2.02) and 2.39 (1.32-4.33), retinopathy: 4.41 (2.03-9.57), 1.77 (1.17-2.68) and 3.72 (1.85-7.47) and autonomic dysfunction: 3.25 (1.65-6.41), 1.64 (1.12-2.39) and 2.89 (1.54-5.42). Conclusions 24 h-CASP and 24 h-CPP was higher in patients vs. controls and increased with diabetic complications independently of covariates. Furthermore, 24 h-CASP was stronger associated to complications than 24 h-SBP. The prognostic significance of 24 h-CASP and 24 h-CPP needs to be determined in follow-up studies. Trial

  2. [Ambulatory 24-hour blood pressure monitoring in patients with resistant hypertension].

    PubMed

    Sznajderman, M; Popławska, W; Cybulska, I; Niegowska, J; Makowiecka-Cieśla, M; Baranowski, R

    1990-01-01

    The aim of the study was to assess the usefulness of 24-hour blood pressure (BP) and heart rate (HR) monitoring in patients with "resistant" hypertension. 30 patients (44.1 +/- 9.9 years) with diastolic BP 100 mm Hg or more in spite of treatment with three or more antihypertensive drugs were studied. Ambulatory recording of BP and HR was performed by means of Del Mar Avionics monitoring system 9000. Mean recording time was 21.5 hours and mean number of measurements during one recording--56.7. Mean ambulatory systolic and diastolic BP values were significantly lower than mean value of three casual measurements (146.0 +/- 24.6 vs 171.5 +/- 21.2 mm Hg for systolic and 97.2 +/- 11.3 vs 110.4 +/- 7.5 mm Hg for diastolic BP p less than 0.01) In 14 (46.6%) systolic BP and in 10 patients (33.3%) diastolic BP were normal. The patients with normal and abnormal ambulatory BP recordings did not differ in regard to age and mean clinic BP levels. However, patients with abnormal ambulatory BP recordings were more often overweight and showed a greater frequency of left ventricular hypertrophy and family history of hypertension and its complications. The results of the study show that ambulatory BP monitoring may be of value in assessing the response to antihypertensive treatment in patients with so called resistant hypertension as judged on the basis of clinic pressure. PMID:2074634

  3. Physician-pharmacist co-management and 24-hour blood pressure control.

    PubMed

    Chen, Ziqian; Ernst, Michael E; Ardery, Gail; Xu, Yinghui; Carter, Barry L

    2013-05-01

    The objectives of this study were to compare indices of 24-hour blood pressure (BP) following a physician-pharmacist collaborative intervention and to describe the associated changes in antihypertensive medications. This was a secondary analysis of a prospective, cluster-randomized clinical trial conducted in 6 family medicine clinics randomized to co-managed (n=3 clinics, 176 patients) or control (n=3 clinics, 198 patients) groups. Mean ambulatory systolic BP (SBP) was significantly lower in the co-managed vs the control group: daytime BP 122.8 mm Hg vs 134.4 mm Hg (P<.001); nighttime SBP 114.8 mm Hg vs 123.7 mm Hg (P<.001); and 24-hour SBP 120.4 mm Hg vs 131.8 mm Hg (P<.001), respectively. Significantly more drug changes were made in the co-managed than in the control group (2.7 vs 1.1 changes per patient, P<.001), and there was greater diuretic use in co-managed patients (79.6% vs 62.6%, P<.001). Ambulatory BPs were significantly lower for the patients who had a diuretic added during the first month compared with those who never had a diuretic added (P<.01). Physician-pharmacist co-management significantly improved ambulatory BP compared with the control group. Antihypertensive drug therapy was intensified much more for patients in the co-managed group. PMID:23614849

  4. Sleep-Disordered Breathing and 24-Hour Blood Pressure Pattern Among Older Adults

    PubMed Central

    White, William B.; Kutner, Michael; Ouslander, Joseph G.; Bliwise, Donald L.

    2009-01-01

    Background To examine the association between sleep-disordered breathing (SDB) and 24-hour blood pressure (BP) pattern among community-dwelling older adults. Methods A convenience sample of 70 community-dwelling older adults, recruited from senior housing, community centers, and learning centers, were admitted to General Clinical Research Center, Emory University Hospital, Atlanta, Ga. Information regarding demographic and clinical history was obtained using questionnaires. Twenty-four–hour BP monitoring in supine position was performed using Spacelabs model 20207. Breathing during sleep was monitored with the use of a modified sleep recording system (Embletta, PDS), which monitors nasal and oral airflow, chest and abdominal movements, and pulse oximetry. Night time–daytime (night-day) BP ratio (average night-time BP divided by daytime BP) was calculated both for systolic and diastolic BPs. Results Sixty-nine participants, mean age 74.9 ± 6.4 years (41 [57%] women), completed the study. The mean apnea-hypopnea index (AHI) was 13 ± 13 per hour of sleep, and 20 participants (29%) had AHI ≥15 per hour of sleep, indicating moderate to severe SDB. Moderate to severe SDB (AHI ≥15 per hour of sleep) was significantly associated with nocturnal hypertension, whereas there was no statistically significant difference in wake-time BP between those with and without moderate to severe SDB. Stepwise multiple regressions showed that AHI independently predicted increased night-day systolic and night-day diastolic BP ratio, even after controlling for nocturia frequency. Conclusions The results indicate increased BP load associated with increased AHI in this group of older adults. This increased BP load may contribute to increased hypertension-related morbidity and disease burden. PMID:19196901

  5. The impact of kidney transplantation on 24-hour ambulatory blood pressure in end-stage renal disease patients.

    PubMed

    Lee, Myung Hyun; Ko, Kyung Min; Ahn, Seung Won; Bae, Myoung Nam; Choi, Bum Soon; Park, Cheol Whee; Kim, Yong-Soo; Yang, Chul Woo; Chung, Byung Ha

    2015-06-01

    In this study, we prospectively investigated the impact of kidney transplantation (KT) on the status of hypertension, including circadian rhythm in end-stage renal disease (ESRD) patients. We performed 24-hour ambulatory blood pressure (BP) monitoring and office BP measurement in 48 patients before and 1 year after KT. According to the nocturnal reduction in systolic BP (ΔSBP), the patients were divided into dippers, non-dippers, and reverse dippers. After KT, the mean BP value in office BP and 24-hour ambulatory BP monitoring did not change, but the proportion of patients taking anti-hypertensive drugs and the pill number significantly decreased. In contrast, the mean ΔSBP significantly decreased, and the proportion of non-dippers and reverse dippers did not decrease. Decrease in ΔSBP after KT was associated with inferior allograft function during follow-up. Our study suggests that KT improved the overall BP level, but it did not affect abnormal circadian rhythm in ESRD patients. PMID:26051924

  6. 24-Hour Academic Libraries: Adjusting to Change

    ERIC Educational Resources Information Center

    Bowman, Adam C.

    2013-01-01

    The purpose of this study was to explore the adaptive measures that academic libraries perform when implementing and operating a 24-hour schedule. Five in-depth interviews were conducted with current managerial-level librarians at 24-hour academic libraries. The exploratory interviews revealed similar measures for security, budgeting, employee…

  7. The pressor effect of NO synthase inhibition correlates to pre-existing systolic BP in the rat.

    PubMed

    Elayan, Hamzeh H; Kennedy, Brian P; Ziegler, Michael G

    2002-01-10

    A number of studies have found that the vasopressor effect of nitric oxide (NO) synthase inhibition is small following treatment with hypotensive agents but is enhanced after hypertensive agents, and have implicated NO in the mechanism of action of these drugs. We investigated the hypothesis that the rate of vascular NO synthesis is directly related to blood pressure. The vasopressor effect of 10 mg/kg of L-nitro-L-arginine methyl ester (L-NAME) was studied in relation to changes in BP induced by a variety of treatments in both pentobarbital sodium anesthetized and pithed rats. BP reductions were induced by blood withdrawal, surgery and pithing. BP increases were made by injecting 10 and 15 microg/kg boluses of phenylephrine or by injecting 5% albumin solution. Pithing decreased baseline BP and attenuated the vasopressor effect of L-NAME while phenylephrine increased both BP levels and the hypertensive effect of L-NAME. Volume expansion with 5% albumin solution increased both BP and the vasopressor effect of L-NAME. Both surgery (abdominal incision) and withdrawal of 1 ml blood reduced BP and attenuated the pressor effect of L-NAME. When the results of all these studies were combined, systolic BP was found to correlate strongly with the vasopressor effect of L-NAME (R2 = 0.73, P < 0.0001). Diastolic BP correlated less well with L-NAME (R2 = 0.36, P < 0.0003). The results suggest that shear stress generated by blood flow during the systole releases NO, and lowers BP. The pressor effect of NO synthase inhibition is closely related to pre-existing systolic BP. PMID:11871783

  8. Depressive Symptoms and 24-Hour Ambulatory Blood Pressure in Africans: The SABPA Study

    PubMed Central

    Hamer, Mark; Frasure-Smith, Nancy; Lespérance, François; Harvey, Brian H.; Malan, Nico T.; Malan, Leoné

    2012-01-01

    Disturbances in circadian rhythm might play a central role in the neurobiology of depression. We examined the association between depressive symptoms and 24-hour ambulatory BP in a sample of 405 (197 black and 208 Caucasian) urbanized African teachers aged 25 to 60 yrs (mean 44.6 ± 9.6 yrs). Depressive symptoms were assessed using the self-administered 9-item Patient Health Questionnaire (PHQ-9). After adjusting for age, sex, and ethnicity, participants with severe depressive symptoms (PHQ-9 ≥ 15) had higher odds of hypertension defined from ambulatory BP and/or use of antihypertensive medication (odds ratio = 2.19, 95% CI, 1.00–4.90) in comparison to participants with no symptoms. Compared to Caucasians with no depressive symptoms, those with severe symptoms had blunted nocturnal systolic BP drop of 4.7 mmHg (95% CI, −0.5 to 10.0, P = 0.07). In summary, depressive symptoms were associated with the circadian BP profile in black and Caucasian Africans. PMID:22028954

  9. Validation of the BPLab® 24-hour blood pressure monitoring system in a pediatric population according to the 1993 British Hypertension Society protocol

    PubMed Central

    Ledyaev, Mikhail Y; Stepanova, Olga V; Ledyaeva, Anastasia M

    2015-01-01

    Background Automatic 24-hour ambulatory blood pressure (BP) monitoring (ABPM) is a basic procedure performed in adults with arterial hypertension, but ABPM monitors have become widely used in pediatric practice only recently. The main problem is the lack of common normative data sets for ABPM in children and the small number of appropriate monitors that can be used for analysis of the 24-hour BP profile in this age group. The aim of this study was to validate the BPLab® ABPM monitor according to the 1993 British Hypertension Society (BHS-93) protocol, as well as to work out solutions regarding the feasibility of this device in pediatric practice. Methods Our study included 30 children of both sexes and aged 5–15 years, ie, “older” children according to the BHS-93 protocol. Before starting the study, we obtained ethical approval from the regional scientific ethics committee. All participants and their parents signed their written consent for participation in the study. The data were simultaneously obtained by three experts, who had completed a noninvasive BP measurement training course. BP values were measured using the Korotkoff auscultatory method (Phase I for systolic BP and Phase V for diastolic BP). Discrepancies in the systolic and diastolic BP measurements (n=180; 90 for each expert) were analyzed according to the criteria specified in the BHS-93 protocol. Results The device was graded “A” for both systolic BP and diastolic BP according to the criteria of the BHS-93 protocol. Conclusion The BPLab ABPM device may be recommended for extensive pediatric use. PMID:25674018

  10. The 24-Hour Mathematical Modeling Challenge

    ERIC Educational Resources Information Center

    Galluzzo, Benjamin J.; Wendt, Theodore J.

    2015-01-01

    Across the mathematics curriculum there is a renewed emphasis on applications of mathematics and on mathematical modeling. Providing students with modeling experiences beyond the ordinary classroom setting remains a challenge, however. In this article, we describe the 24-hour Mathematical Modeling Challenge, an extracurricular event that exposes…

  11. Beetroot supplementation lowers daily systolic blood pressure in older, overweight subjects.

    PubMed

    Jajja, A; Sutyarjoko, A; Lara, J; Rennie, K; Brandt, K; Qadir, O; Siervo, M

    2014-10-01

    Although inorganic nitrate and beetroot juice supplementation are associated with decreased systolic blood pressure (BP), these results have primarily been obtained from short-term trials that focused on healthy young adults. Therefore, we hypothesized that oral supplementation of beetroot juice concentrate would decrease systolic BP in overweight older participants but that the decline in BP would not be sustained after a 1-week interruption of the beetroot juice supplementation. For 3 weeks, 24 participants were randomized to either the beetroot juice concentrate or blackcurrant juice group, with a 1-week postsupplementation phase (week 4). Changes in systolic and diastolic BP were assessed during the supplementation and postsupplementation phases. Blood pressure was measured using 3 different methods: (1) resting clinic BP, (2) 24-hour ambulatory BP monitoring, and (3) home monitoring of daily resting BP. The first 2 methods were applied at baseline and after weeks 3 and 4. Daily measurements were conducted throughout the study, with 21 subjects completing the study (beetroot/blackcurrant = 10/11; male/female = 12/9; age = 62.0 ± 1.4 years; body mass index = 30.1 ± 1.2 kg/m(2)). After 3 weeks, beetroot juice supplementation was not associated with significant changes in resting clinic BP or 24-hour ABPM. Conversely, beetroot juice concentrate reduced daily systolic BP after 3 weeks (-7.3 ± 5.9 mm Hg, P = .02); however, the effect was not maintained after the interruption of the supplementation (week 4, 2.8 ± 6.1 mm Hg, P = .09). In overweight older subjects, beetroot juice concentrate supplementation was associated with beneficial effects on daily systolic BP, although the effects were not significant when measured by 24-hour ABPM or resting clinic BP. PMID:25294299

  12. Longitudinal Study of Left Ventricular Mass Growth: Comparative Study of Clinic and Ambulatory Systolic Blood Pressure in Chronic Kidney Disease.

    PubMed

    Agarwal, Rajiv

    2016-04-01

    Left ventricular (LV) hypertrophy is an established cardiovascular risk factor, yet little is known about its trajectory in people with chronic kidney disease. The goal of this prospective research study was to describe the trajectory of LV mass index, its relationship with blood pressure (BP), and specifically to compare the relationship of BP measured in the clinic and 24-hour ambulatory BP monitoring with LV mass index. Among 274 veterans with chronic kidney disease followed for over ≤ 4 years, the rate of growth of log LV mass index was inversely related to baseline LV mass index; it was rapid in the first 2 years, and plateaued subsequently. Systolic BP also significantly increased, but linearly, 1.7 mm Hg/y by clinic measurements and 1.8 mm Hg/y by 24-hour ambulatory BP. Cross-sectional and longitudinal associations of both clinic BP and 24-hour ambulatory BP with LV mass index were similar; both BP recording methods were associated with LV mass index and its growth over time. Controlled hypertension, masked uncontrolled hypertension, and uncontrolled hypertension categories had increasing LV mass index when diagnosed by 24-hour ambulatory and awake BP (P<0.05 for linear trend) but not sleep BP. After accounting for clinic BP both at baseline and longitudinally, LV mass index among individuals was additionally predicted by the difference in sleep systolic BP and clinic systolic BP (P=0.032). In conclusion, among people with chronic kidney disease, the growth of LV mass index is rapid. Research-grade clinic BP is useful to assess LV mass index and its growth over time. PMID:26831191

  13. 24-hour central blood pressure and intermediate cardiovascular phenotypes in untreated subjects

    PubMed Central

    Bednarek, Agnieszka; Jankowski, Piotr; Olszanecka, Agnieszka; Windak, Adam; Kawecka-Jaszcz, Kalina; Czarnecka, Danuta

    2014-01-01

    Background: Recently, 24-hour monitoring of central systolic blood pressure (SBP) has become available. However, the relation between end-organ damage and the 24-hour central SBP profile and variability has not so far been analyzed. Therefore, the aim of this cross-sectional study was to evaluate the relation between 24-hour central SBP, 24-hour central SBP profile as well as central SBP short-term variability and parameters of cardiac and vascular intermediate phenotypes. Methods: The study group consisted of 50 patients with newly diagnosed, untreated hypertension (age 40.4 ± 11.5 years, 35 men) and 50 normotensive subjects (age 38.3 ± 12.0 years, 35 men). Applanation tonometry of the radial artery and the “n-point forward moving average” method were used to determine 24-hour central SBP. Each study participant underwent echocardiography and carotid ultrasonography. Results: 24-hour, daytime, and nighttime central SBP was related to left ventricle end-diastole diameter (p < 0.05), left ventricular mass index (p < 0.001), relative wall thickness (p < 0.05), E/E’ ratio (p < 0.01), and left atrium volume (p < 0.01). The nocturnal central SBP fall was not related to any of the mentioned parameters, whereas parameters of short-term variability were related to IMT in hypertensives only (p < 0.05). Conclusions: The present study showed that 24-hour central SBP is related to intermediate cardiac phenotypes as assessed by echocardiography whereas short-term central SBP variability is mainly related to vascular phenotype as determined by IMT. PMID:25628959

  14. Human prolactin - 24-hour pattern with increased release during sleep.

    NASA Technical Reports Server (NTRS)

    Sassin, J. F.; Weitzman, E. D.; Kapen, S.; Frantz, A. G.

    1972-01-01

    Human prolactin was measured in plasma by radioimmunoassay at 20-minute intervals for a 24-hour period in each of six normal adults, whose sleep-wake cycles were monitored polygraphically. A marked diurnal variation in plasma concentrations was demonstrated, with highest values during sleep. Periods of episodic release occurred throughout the 24 hours.

  15. HEART RATE VARIABILITY AND 24-HOUR MINIMUM HEART RATE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heart rate variability (HRV) indices based on 24-hour electrocardiograph recordings have been used in clinical research studies to assess the aggregate activity of the autonomic nervous system. While 24-hour HRV is generally considered non-invasive, use in research protocols typically involves cons...

  16. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  17. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  18. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  19. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  20. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  1. [24-hour blood pressure measurement in normal pregnancy in hypertensive pregnant patients].

    PubMed

    Rath, W; Schrader, J; Guhlke, U; Buhr-Schinner, H; Haupt, A; Kramer, A; Kuhn, W

    1990-08-01

    Noninvasive 24-hour ambulatory blood pressure monitoring was performed in 17 normotensive and 19 preeclamptic pregnant women. The normotensive women showed a significant nightly decline in their systolic and diastolic blood pressure. In contrast, the preeclamptic women demonstrated either an attenuated circadian rhythm or no circadian rhythm at all. This result was even more pronounced in patients with severe hypertension, some of whom had a nocturnal increase in blood pressure in spite of being treated with antihypertensive drugs in an evening dose. The lack of nocturnal blood pressure decrease was also found 24 hours post partum. In summary, these results suggest that preeclamptic women are endangered by hypertensive emergencies mostly during the night. Therefore blood pressure controls should be extended into the night, and antihypertensive drugs should also be given in a sufficient evening dose. PMID:2214601

  2. Effect of overtime work on 24-hour ambulatory blood pressure.

    PubMed

    Hayashi, T; Kobayashi, Y; Yamaoka, K; Yano, E

    1996-10-01

    Recently, the adverse effects of long working hours on the cardiovascular systems of workers in Japan, including "Karoshi" (death from overwork), have been the focus of social concern. However, conventional methods of health checkups are often unable to detect the early signs of such adverse effects. To evaluate the influence of overtime work on the cardiovascular system, we compared 24-hour blood pressure measurements among several groups of male white-collar workers. As a result, for those with normal blood pressure and those with mild hypertension, the 24-hour average blood pressure of the overtime groups was higher than that of the control groups; for those who periodically did overtime work, the 24-hour average blood pressure and heart rate during the busy period increased. These results indicate that the burden on the cardiovascular system of white-collar workers increases with overtime work. PMID:8899576

  3. Chapter 4: 24-hour recall and diet record methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The two methods described in this chapter, the 24-hour dietary recall (24hdr) and the food record (FR) method, are the currently preferred methods of dietary intake assessment, and are based on foods and amounts actually consumed by an individual on one or more specific days. This minimizes some sou...

  4. The 24 Hours before Hospitalization: Factors Related to Suicide Attempting.

    ERIC Educational Resources Information Center

    Chiles, John A.; And Others

    1986-01-01

    Psychiatric inpatients (N=59) were interviewd concerning psychological and environmental events that occurred in the 24 hours prior to their hospitalization. Suicide attempters were more likely to have used alcohol or marijuana and less likely to have contacted a health care professional than suicide ideators, even when past history of suicide…

  5. Seasonal changes of 24-hour intraocular pressure rhythm in healthy Shanghai population

    PubMed Central

    Cheng, Jingyi; Xiao, Ming; Xu, Huan; Fang, Shaobin; Chen, Xu; Kong, Xiangmei; Sun, Xinghuai

    2016-01-01

    Abstract The aim of the present study was to investigate and compare the 24-hour intraocular pressure (IOP) rhythms in winter and summer in the healthy population of Shanghai, China. This is a cross-sectional study in which 24-hour IOP measurements were taken for all eligible healthy volunteers in winter and summer, respectively, and the temperature, hours of sunlight (sunlight time), and circulatory parameters, including heart rate, systolic blood pressure, and diastolic blood pressure, were also recorded. The 24-hour IOP curves and IOP parameters (mean, peak, trough, and fluctuation of IOP together with the diurnal-to-nocturnal IOP change) in winter and summer were obtained and compared. The magnitude of IOP changes from summer to winter was also calculated. A total of 29 participants (58 eyes), 14 (48.28%) male and 15 (51.72%) female, aged 43.66 ± 12.20 (19–61) years, were considered eligible for this study. Generally, IOP decreased progressively before noon, increased notably in the nocturnal period, and peaked at 12:00 am in winter and at 2:00 am in summer. The pattern of 24-hour IOP in winter and summer was significantly different (P = 0.002). The average IOPs from 4:00 pm to 8:00 am, except for 6:00 am, were significantly higher in winter (P < 0.05). However, no significant differences were shown after adjusting for temperature and/or sunlight time. From summer to winter, the extent of IOP increase was mostly around 0 to 3 mm Hg, and the IOPs increased more significantly in the nocturnal period than in the diurnal period (P = 0.05). The 24-hour IOP rhythms were different in winter and summer, with higher IOP level in winter. Temperature and sunlight time, which are independent of heart rate and blood pressure, affected the 24-hour IOP rhythms in healthy people in Shanghai, China. Further investigations are expected for the rhythm of some endogenous substance secretion and the inner mechanism of regulation of IOP. PMID:27495076

  6. Seasonal changes of 24-hour intraocular pressure rhythm in healthy Shanghai population.

    PubMed

    Cheng, Jingyi; Xiao, Ming; Xu, Huan; Fang, Shaobin; Chen, Xu; Kong, Xiangmei; Sun, Xinghuai

    2016-08-01

    The aim of the present study was to investigate and compare the 24-hour intraocular pressure (IOP) rhythms in winter and summer in the healthy population of Shanghai, China.This is a cross-sectional study in which 24-hour IOP measurements were taken for all eligible healthy volunteers in winter and summer, respectively, and the temperature, hours of sunlight (sunlight time), and circulatory parameters, including heart rate, systolic blood pressure, and diastolic blood pressure, were also recorded. The 24-hour IOP curves and IOP parameters (mean, peak, trough, and fluctuation of IOP together with the diurnal-to-nocturnal IOP change) in winter and summer were obtained and compared. The magnitude of IOP changes from summer to winter was also calculated.A total of 29 participants (58 eyes), 14 (48.28%) male and 15 (51.72%) female, aged 43.66 ± 12.20 (19-61) years, were considered eligible for this study. Generally, IOP decreased progressively before noon, increased notably in the nocturnal period, and peaked at 12:00 AM in winter and at 2:00 AM in summer. The pattern of 24-hour IOP in winter and summer was significantly different (P = 0.002). The average IOPs from 4:00 PM to 8:00 AM, except for 6:00 AM, were significantly higher in winter (P < 0.05). However, no significant differences were shown after adjusting for temperature and/or sunlight time. From summer to winter, the extent of IOP increase was mostly around 0 to 3 mm Hg, and the IOPs increased more significantly in the nocturnal period than in the diurnal period (P = 0.05).The 24-hour IOP rhythms were different in winter and summer, with higher IOP level in winter. Temperature and sunlight time, which are independent of heart rate and blood pressure, affected the 24-hour IOP rhythms in healthy people in Shanghai, China. Further investigations are expected for the rhythm of some endogenous substance secretion and the inner mechanism of regulation of IOP. PMID:27495076

  7. Breast milk intake: 12 hour versus 24 hour assessment.

    PubMed

    De Carvalho, M; Pittard, W

    1982-11-01

    Letter to the editor commenting on "Clinical and field studies of human lactation: methodological considerations," by Brown et al. The point is made that in test-weighing infants to estimate breast milk intake, culture related breastfeeding practices must be studied before a 12 hour test period is used to estimate intake for a complete 24 hour period. In western cultures milk intake between 7 am and 7 pm was found to differ significantly from intake between 7 pm and 7 am, whereas in a Bangladesh study milk intake during the 2 12 hour periods was comparable. PMID:7137079

  8. [Isolation of Mycobacterium avium complex from the "24-hour bath"].

    PubMed

    Saito, H; Murakami, K; Ishii, N; Kwon, H H

    2000-01-01

    The "24-HOUR BATH" is an apparatus which circulates the bath water, keeps it clean and warm, and makes it possible to take a bath at any time during the day or night. It consists of apparatus for cleaning (sponge or mesh filter and filter material), heating (ceramic heater), and sterilizing (UV lamp). Recently, three cases of skin disease due to M. avium infection in private homes, in which "24-HOUR BATH" water was suspected to be the source of infection, have been reported. We attempted to isolate M. avium complex from the water (32 specimens), sponge filter (29 specimens), and filter material (32 specimens) of the "24-HOUR BATH". One hundred-ml samples of bath water, and 50-ml samples of rinse from a sponge filter or filter material were centrifuged at 3000 rpm for 20 min. Sediment was suspended in distilled water and a smear was prepared, and then digested and decontaminated with 2% sodium hydroxide. The processed specimens were cultured on 2% Ogawa medium containing ofloxacin (1 microgram/ml) and ethambutol (2.5 micrograms/ml) for 8 weeks at 37 degrees C. Positive smears were 3 (9.4%), 25 (86.2%) and 25 (78.1%) specimens from the water, sponge and filter material, respectively. A few bacterial clumps were observed, especially in the sponge specimens. The number of positive culture was 5 (15.6%), 24 (82.8%) and 25 (78.1%) from the water, sponge and filter material, respectively. Among them the number of Runyon's Group III-positive cultures was 5 (100%), 22 (91.7%) and 20 (80%) in the water, sponge, and filter material specimens, respectively. In most cases, cultures were positive for both the sponge and filter material specimens. All of the Group III mycobacteria were smooth, grew at 28, 37, 42, and 45 degrees C, negative for niacin, nitrate reductase, semiquantitative catalase, urease and Tween80 hydrolysis, and positive for 68 degrees C catalase. All of the strains reacted with M. avium complex AccuProbe and M. avium AccuProbe, but none of the strains reacted

  9. [A validation of the data obtained with the simultaneous recording of blood pressure and the 24-hour electrocardiogram].

    PubMed

    Germanò, G; Caparra, A; Valentino, S; Coia, F; Federico, L; Santucci, A

    1993-06-01

    Aim of this study was to evaluate the blood pressure (BP) measurement reliability of a light weight ambulatory BP and ECG recorder. Micro AM is a new 300 g portable apparatus that combines in one device both the ambulatory BP and solid state ECG recording. The dimensions of the Micro AM are 75 x 140 x 29 mm. The monitor measures BP using Korotkoff phase 1 for systolic and phase 5 for diastolic BP, and concurrently measures oscillometric BP, one method validating the other. In addition, the manual and programmed BP measurement modes can be supplemented by an "intelligent" mode in which the ECG triggers an ambulatory BP reading during an abnormal ST segment change. A standard mercury manometer was connected with the cuff of the Micro AM with a Y-shaped part, and 12 BP measurements were simultaneously taken at 5 min intervals by the automatic device in auscultatory mode and by a trained technician in 86 normotensive volunteers (aged from 18 to 44 years, 37 males and 49 females). The algebraic differences, the frequency distribution and the difference distribution of systolic and diastolic data between the 2 methods were calculated. The results show that the automatic method gives values for systolic BP that are lower than conventional ones (average differences -0.643 mmHg), whereas for diastolic BP, the values are higher (average differences +0.229 mmHg). Then, Student's paired t-test was used to evaluate statistically significant differences. The test relative to systolic BP was significant to the critical level of 0.1%, but the differences being 3 times smaller than the instrumental tolerance. On the contrary, diastolic BP differences were non significant. In conclusion, we found a good agreement between BP recorded automatically and by sphygmomanometer. PMID:8402748

  10. The 24-hour pulse wave velocity, aortic augmentation index, and central blood pressure in normotensive volunteers

    PubMed Central

    Kuznetsova, Tatyana Y; Korneva, Viktoria A; Bryantseva, Evgeniya N; Barkan, Vitaliy S; Orlov, Artemy V; Posokhov, Igor N; Rogoza, Anatoly N

    2014-01-01

    The purpose of this study was to examine the pulse wave velocity, aortic augmentation index corrected for heart rate 75 (AIx@75), and central systolic and diastolic blood pressure during 24-hour monitoring in normotensive volunteers. Overall, 467 subjects (206 men and 261 women) were recruited in this study. Participants were excluded from the study if they were less than 19 years of age, had blood test abnormalities, had a body mass index greater than 2 7.5 kg/m2, had impaired glucose tolerance, or had hypotension or hypertension. Ambulatory blood pressure monitoring (ABPM) with the BPLab® device was performed in each subject. ABPM waveforms were analyzed using the special automatic Vasotens® algorithm, which allows the calculation of pulse wave velocity, AIx@75, central systolic and diastolic blood pressure for “24-hour”, “awake”, and “asleep” periods. Circadian rhythms and sex differences in these indexes were identified. Pending further validation in prospective outcome-based studies, our data may be used as preliminary diagnostic values for the BPLab ABPM additional index in adult subjects. PMID:24812515

  11. Physical and Mental Health of Patients Immediately After Discharge From Intensive Care Unit and 24 Hours Later

    PubMed Central

    Momennasab, Marzieh; Ghahramani, Tahereh; Yektatalab, Shahrzad; Zand, Farid

    2016-01-01

    Background: Monitoring the health status of patients discharged from intensive care units is a crucial method of service evaluation. Objectives: This study aimed to assess the physical and mental health status of patients immediately after discharge from the ICU and 24 hours later. Patients and Methods: This descriptive comparative study was conducted on 104 patients discharged from the ICUs of a referral trauma center in Shiraz, Southwest Iran. Physical parameters, including respiratory rate, need for supplemental oxygen, heart rate, blood pressure, and need for cardiac monitoring, were assessed. Hospital anxiety and depression scale (HADS) was used for mental health evaluation. The mental and physical status of patients were assessed before ICU discharge and 24 hours later; data were recorded in information forms and were analyzed using SPSS statistical software version 17. Results: At the time of discharge, the respiratory rate of 28% of the participants was more than 24 minutes, and 95.2% received supplemental oxygen. However, after 24 hours these values decreased to 10% and 21.6%, respectively. The mean heart rate and systolic blood pressure were within the normal range at both time points. Additionally, 63% of the patients had anxiety scores above 11 at both time points, reflecting high anxiety. The number of patients who reported depression increased from 58.7% at ICU discharge to 69.6% after 24 hours. Conclusions: Despite the considerable improvement in most of the patients’ physical condition in the first 24 hours after discharge from ICU, a significant number of them remain at risk for the development of adverse effects from this transition. The high prevalence of mental health disorders in these patients reveals the necessity to conduct follow-up consultations. PMID:27218059

  12. Managing sleep and wakefulness in a 24-hour world

    PubMed Central

    Coveney, Catherine M

    2014-01-01

    This article contributes to literature on the sociology of sleep by exploring the sleeping practices and subjective sleep experiences of two social groups: shift workers and students. It draws on data, collected in the UK from 25 semi-structured interviews, to discuss the complex ways in which working patterns and social activities impact upon experiences and expectations of sleep in our wired awake world. The data show that, typically, sleep is valued and considered to be important for health, general wellbeing, appearance and physical and cognitive functioning. However, sleep time is often cut back on in favour of work demands and social activities. While shift workers described their efforts to fit in an adequate amount of sleep per 24-hour period, for students, the adoption of a flexible sleep routine was thought to be favourable for maintaining a work–social life balance. Collectively, respondents reported using a wide range of strategies, techniques, technologies and practices to encourage, overcome or delay sleep(iness) and boost, promote or enhance wakefulness/alertness at socially desirable times. The analysis demonstrates how social context impacts not only on how we come to think about sleep and understand it, but also how we manage or self-regulate our sleeping patterns. PMID:23957268

  13. [Necessity of a 24-hour system of blood transfusion testing].

    PubMed

    Kishimoto, Yuji

    2003-01-01

    The preventive effects of a 24-hour system of blood transfusion testing on mistyping of transfused blood was examined. Blood transfusion tests have been performed by blood transfusion technologists during working hours and by physicians at other times. In March 2000, we introduced a system in which technologists perform blood transfusion tests after working hours. Technologists of the Blood Transfusion Unit and Central Clinical Laboratory perform the test jointly, and column agglutination technology was introduced as the test method. A computer system setup exclusively for the testing was also introduced to perform computer cross-matching. Since transfusion error is likely to occur during emergency blood transfusion, a manual was established to prioritize safety. After introduction of the system, mistyping that may have been caused by inaccurate blood test results markedly decreased, confirming the usefulness of this system for prevention of mistyping. In addition, transfusion errors also decreased in wards and the improved system increased the safety of the entire medical care system. The frequency of mistyping was about 1% when physicians performed blood typing, showing the importance of clinical technologists for blood transfusion tests. PMID:12652691

  14. Cognitive Performance during a 24-Hour Cold Exposure Survival Simulation

    PubMed Central

    Hartley, Geoffrey L.; Zaharieva, Dessi; Basset, Fabien A.; Hynes, Zach

    2016-01-01

    Survivor of a ship ground in polar regions may have to wait more than five days before being rescued. Therefore, the purpose of this study was to explore cognitive performance during prolonged cold exposure. Core temperature (Tc) and cognitive test battery (CTB) performance data were collected from eight participants during 24 hours of cold exposure (7.5°C ambient air temperature). Participants (recruited from those who have regular occupational exposure to cold) were instructed that they could freely engage in minimal exercise that was perceived to maintaining a tolerable level of thermal comfort. Despite the active engagement, test conditions were sufficient to significantly decrease Tc after exposure and to eliminate the typical 0.5–1.0°C circadian rise and drop in core temperature throughout a 24 h cycle. Results showed minimal changes in CTB performance regardless of exposure time. Based on the results, it is recommended that survivors who are waiting for rescue should be encouraged to engage in mild physical activity, which could have the benefit of maintaining metabolic heat production, improve motivation, and act as a distractor from cold discomfort. This recommendation should be taken into consideration during future research and when considering guidelines for mandatory survival equipment regarding cognitive performance. PMID:27478839

  15. Cognitive Performance during a 24-Hour Cold Exposure Survival Simulation.

    PubMed

    Taber, Michael J; Hartley, Geoffrey L; McGarr, Gregory W; Zaharieva, Dessi; Basset, Fabien A; Hynes, Zach; Haman, Francois; Pinet, Bernard M; DuCharme, Michel B; Cheung, Stephen S

    2016-01-01

    Survivor of a ship ground in polar regions may have to wait more than five days before being rescued. Therefore, the purpose of this study was to explore cognitive performance during prolonged cold exposure. Core temperature (T c) and cognitive test battery (CTB) performance data were collected from eight participants during 24 hours of cold exposure (7.5°C ambient air temperature). Participants (recruited from those who have regular occupational exposure to cold) were instructed that they could freely engage in minimal exercise that was perceived to maintaining a tolerable level of thermal comfort. Despite the active engagement, test conditions were sufficient to significantly decrease T c after exposure and to eliminate the typical 0.5-1.0°C circadian rise and drop in core temperature throughout a 24 h cycle. Results showed minimal changes in CTB performance regardless of exposure time. Based on the results, it is recommended that survivors who are waiting for rescue should be encouraged to engage in mild physical activity, which could have the benefit of maintaining metabolic heat production, improve motivation, and act as a distractor from cold discomfort. This recommendation should be taken into consideration during future research and when considering guidelines for mandatory survival equipment regarding cognitive performance. PMID:27478839

  16. Preparation and results of a 24-hour orbital flight.

    PubMed

    Titov, G S

    1963-01-01

    The space age presents man with unprecedented opportunities for discovery and for cooperative endeavors to benefit all mankind. My flight of August 6-7, 1961 was conducted for the purpose of determining whether man can stay and work effectively and whether all systems of the spaceship can operate successfully during a period of 24 hours in space. The flight of Vostok II represents an experimental step in a logical sequence which included the first earth orbiting flight of USSR citizen Yuri A. Gagarin. Preparation for the flight included the study of theoretical and applied subjects, testing in various kinds of apparatus which provide acceleration, heat and isolation experience, brief airborne weightless flights and parachute landings, in addition to extensive training in a real spacecraft having simulators for normal and emergency contingencies of space flight. The actual flight was therefore carried out with a sense of confidence and familiarity and with continuous close radio contact with ground centers from whom my fellow cosmonauts served as spokesmen. Sequential boosters totaling 600 000 kg thrust placed the 4731 kg spaceship into a perfect orbit varying in altitude from 178-246 km in a plane 64 degrees 58' inclined to the equator. The spaceship made 17 orbits around the earth landing 25 hours, 18 minutes after take-off. The cabin had full atmospheric pressure and a comfortable habitability which could be extended for 10 days. I was able to maneuver the spaceship and perform many other control functions, make observations and take pictures of the earth and its cloud cover, eat meals and sleep all with good efficiency. I experienced mild symptoms suggestive of seasickness which were aggravated by head turning, ameliorated by sleep and entirely relieved by resumption of g-loading during descent. Altogether analyses of the physical and structural performance of the spaceship and the continuously monitored physiological responses of the pilot indicate that all

  17. [Exercise tolerance in angina patients 3 and 24 hours after administration of a new delayed-action preparation of metoprolol].

    PubMed

    Giusti, C; Verdecchia, P; Pentimone, F; Regoli, F; Cordoni, M; Bongini, A M

    1981-01-01

    To assess the duration of improved exercise tolerance by metoprolol given in a new sustained-release formulation, 40 in-patients affected by stable exercise-induced angina pectoris received single-blind placebo in day 1 and thereafter, in double-blind cross-over once daily administration, metoprolol RETARD 100 mg and 200 mg in days 3 and 5. Symptom-limited cycloergometric exercise tests were performed at 3 and 24 hours after placebo and after each of the two doses of metoprolol RETARD. Duration of exercise, maximal workload and total work performed did significantly increase at 3 and 24 hours after metoprolol RETARD 100 mg (P less than 0.01) and 200 mg (P less than 0.01), without any significant difference between the two doses. Peak systolic arterial pressure and heart rate were lowered by metoprolol RETARD 200 mg at 3 (P less than 0.01) and 24 (P less than 0.01) hours, whereas only the peak heart rate at 3 hours was lowered (P less than 0.05) by the 100 mg dose. It is concluded that in patients with stable exercise-induced angina pectoris, metoprolol RETARD 200 mg appears to be able to increase exercise tolerance and to reduce exercise-induced myocardial oxygen consumption throughout 24 hours period. This may justify a once daily dosing schedule of the 200 mg dose, aimed at improving patient compliance. PMID:7343379

  18. Systolic arrays

    SciTech Connect

    Moore, W.R.; McCabe, A.P.H.; Vrquhart, R.B.

    1987-01-01

    Selected Contents of this book are: Efficient Systolic Arrays for the Solution of Toeplitz Systems, The Derivation and Utilization of Bit Level Systolic Array Architectures, an Efficient Systolic Array for Distance Computation Required in a Video-Codec Based Motion-Detection, On Realizations of Least-Squares Estimation and Kalman Filtering by Systolic Arrays, and Comparison of Systolic and SIMD Architectures for Computer Vision Computations.

  19. A comparison between 24-hour and 2-hour urine collection for the determination of proteinuria.

    PubMed

    Somanathan, N; Farrell, T; Galimberti, A

    2003-07-01

    Proteinuria is one of the fundamental criteria for the diagnosis of pre-eclampsia with quantitative assessment based on the 24-hour urine protein estimation as the gold standard. This study was undertaken to determine whether a 2-hour protein estimation correlated with that of a formal 24-hour collection. Thirty women with proteinuric hypertension were recruited. There was significant correlation between the 2-hour and 24-hour urine protein levels (Pearson's correlation coefficient 0.76 (P 0.000). A positive 2-hour test was associated more closely with significant levels of 24-hour proteinuria than dipstick analysis alone. We conclude from this study that a random 2-hour sample could be used for the initial assessment of proteinuria and so avoid the delay associated with 24-hour quantification of urinary protein. PMID:12881076

  20. Recruiting Strategy and 24-Hour Biomonitoring of Paraquat in Agricultural Workers

    PubMed Central

    Park, Eun-Kee; Tagles, Hector Duarte; Gee, Shirley J.; Hammock, Bruce D.; Lee, Kiyoung; Schenker, Marc B.

    2010-01-01

    The objectives of this study were to recruit agricultural workers in Costa Rica to participate in a 24-hour urine collection for paraquat exposure assessment and to compare the 24-hour sampling to end-of-shift sampling. The authors recruited 187 handlers and 54 nonhandlers from coffee, banana, and palm oil plantations. The completeness of 24-hour urine samples collected (a total of 393 samples) was confirmed by questionnaire and urinary creatinine level. For a subset of 12 samples, the absorbed paraquat level was determined in 24-hours and end-of-shift spot urine samples. The participation rate for handlers was ~90%. The completeness of 24-hour urine collections was verified as the overall average of creatinine levels from 393 urines (1.11 ± 0.50 g/L). A total of 92.4% to 96.7% of urine samples were considered within the acceptable range of urinary creatinine, whereas 94.7% of the samples were described as “complete” from the questionnaire. Measured creatinine correlated well to predicted values (r = .327, p = .0024, 95% CI .12–.51). Detected paraquat levels in spot urine samples had a sensitivity of 96.9% at the high specificity of 100% compared to 24-hour urine samples as the gold standard. There was a significant (p < .0001) correlation between spot and 24-hour urine paraquat levels (r = .7825, 95% CI .61–.88). The recruiting strategy was successful in getting 24-hour urine samples from a farm worker population. Comparison between the paraquat levels in spot and 24-hour urine samples demonstrated that for this compound, end-of-shift spot urine samples would be an appropriate substitute for 24-hour collections. PMID:19064412

  1. Enhanced carotid-cardiac baroreflex response and elimination of orthostatic hypotension 24 hours after acute exercise in paraplegics

    NASA Technical Reports Server (NTRS)

    Engelke, K. A.; Shea, J. D.; Doerr, D. F.; Convertino, V. A.

    1992-01-01

    To test the hypothesis that an acute bout of maximal exercise can ameliorate orthostatic hypotension consequent to prolonged wheelchair confinement, we evaluated heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure responses during 15 minutes of 70 degrees head-up tilt (HUT) in 10 paraplegic subjects 24 hours after arm crank exercise designed to elicit maximal effort, and during a control (no exercise) conditions. Additionally, the carotid baroreceptor stimulus-cardiac response relationship was determined by measurement of R-R interval during external application of graded pressures to the carotid sinuses. One week separated the treatment conditions. The maximum slope of the carotid-cardiac baroreflex response was increased (p = 0.049) by exercise (6.2 +/- 1.7 msec/mmHg) compared to control (3.3 +/- 0.6). During control HUT, HR increased from 61 +/- 1 to 90 +/- 7 bpm (p = 0.001) while SBP decreased from 118 +/- 5 to 106 +/- 9 mmHg (p = 0.025). During HUT 24 hours after exercise, HR increased from 60 +/- 2 to 90 +/- 4 bpm (p = 0.001), but the reduction in SBP was essentially eliminated (116 +/- 5 to 113 +/- 5 mmHg).

  2. Derivation of a measure of systolic blood pressure mutability: a novel information theory-based metric from ambulatory blood pressure tests.

    PubMed

    Contreras, Danitza J; Vogel, Eugenio E; Saravia, Gonzalo; Stockins, Benjamin

    2016-03-01

    We provide ambulatory blood pressure (BP) exams with tools based on information theory to quantify fluctuations thus increasing the capture of dynamic test components. Data from 515 ambulatory 24-hour BP exams were considered. Average age was 54 years, 54% were women, and 53% were under BP treatment. The average systolic pressure (SP) was 127 ± 8 mm Hg. A data compressor (wlzip) designed to recognize meaningful information is invoked to measure mutability which is a form of dynamical variability. For patients with the same average SP, different mutability values are obtained which reflects the differences in dynamical variability. In unadjusted linear regression models, mutability had low association with the mean systolic BP (R(2) = 0.056; P < .000001) but larger association with the SP deviation (R(2) = 0.761; P < .001). Wlzip allows detecting levels of variability in SP that could be hazardous. This new indicator can be easily added to the 24-hour BP monitors improving information toward diagnosis. PMID:26965751

  3. Aldosterone-to-Renin Ratio Is Associated With Reduced 24-Hour Heart Rate Variability and QTc Prolongation in Hypertensive Patients

    PubMed Central

    Grübler, Martin R.; Kienreich, Katharina; Gaksch, Martin; Verheyen, Nicolas; Hartaigh, Bríain Ó.; Fahrleitner-Pammer, Astrid; März, Winfried; Schmid, Johannes; Oberreither, Eva-Maria; Wetzel, Julia; Catena, Cristiana; Sechi, Leonardo A.; Pieske, Burkert; Tomaschitz, Andreas; Pilz, Stefan

    2016-01-01

    Abstract Aldosterone is considered to exert direct effects on the myocardium and the sympathetic nervous system. Both QT time and heart rate (HR) variability (HRV) are considered to be markers of arrhythmic risk and autonomous dysregulation. In this study, we investigated the associations between aldosterone, QT time, and HRV in patients with arterial hypertension. We recruited 477 hypertensive patients (age: 60.2 ± 10.2 years; 52.3% females) with a mean systolic/diastolic 24-hour ambulatory blood pressure monitoring (ABPM) value of 128 ± 12.8/77.1 ± 9.2 mmHg and with a median of 2 (IQR: 1–3) antihypertensive agents. Patients were recruited from the outpatient clinic at the Department of Internal Medicine of the Medical University of Graz, Austria. Blood samples, 24-hour HRV derived from 24-hour blood pressure monitoring (ABPM) and ECG's were obtained. Plasma aldosterone and plasma renin concentrations were measured by means of a radioimmunoassay. Twenty-four-hour urine specimens were collected in parallel with ABPM. Mean QTc was 423.3 ± 42.0 milliseconds for males and 434.7 ± 38.3 milliseconds for females. Mean 24H-HR and 24H-HRV was 71.9 ± 9.8 and 10.0 ± 3.6 bpm, respectively. In linear regression analyses adjusted for age, sex, body mass index, ABPM, and current medication, aldosterone to active renin ratio (AARR) was significantly associated with the QTc interval, a marker for cardiac repolarization abnormalities (mean = 426 ± 42.4 milliseconds; β-coefficient = 0.121; P = 0.03) as well as with the 24-hour heart rate variability a surrogate for autonomic dysfunction (median = 9.67 [IQR = 7.38–12.22 bpm]; β-coefficient = −0.133; P = 0.01). In hypertensive patients, AARR is significantly related to QTc prolongation as well as HRV. Further studies investigating the effects of mineralocorticoid receptor blocker and aldosterone synthase inhibitors on QTc and HRV are warranted

  4. Systolic flow

    SciTech Connect

    Tsay, J.C.; Yuan, S. )

    1990-03-01

    This paper presents a formal algebraic notation to express the global data interacting activities of a systolic array. The notation we use is the generating function. Using generating functions, we can describe the velocity and the moving path of a data stream at any time. Several generating functions can be grouped together to form a systolic flow which can aid the specification, design, and verification of a systolic array.

  5. Different systolic blood pressure targets for people with history of stroke or transient ischaemic attack: PAST-BP (Prevention After Stroke—Blood Pressure) randomised controlled trial

    PubMed Central

    McManus, Richard J; Roalfe, Andrea; Fletcher, Kate; Taylor, Clare J; Martin, Una; Virdee, Satnam; Greenfield, Sheila; Hobbs, F D Richard

    2016-01-01

    Objective To assess whether using intensive blood pressure targets leads to lower blood pressure in a community population of people with prevalent cerebrovascular disease. Design Open label randomised controlled trial. Setting 99 general practices in England, with participants recruited in 2009-11. Participants People with a history of stroke or transient ischaemic attack whose systolic blood pressure was 125 mm Hg or above. Interventions Intensive systolic blood pressure target (<130 mm Hg or 10 mm Hg reduction from baseline if this was <140 mm Hg) or standard target (<140 mm Hg). Apart from the different target, patients in both arms were actively managed in the same way with regular reviews by the primary care team. Main outcome measure Change in systolic blood pressure between baseline and 12 months. Results 529 patients (mean age 72) were enrolled, 266 to the intensive target arm and 263 to the standard target arm, of whom 379 were included in the primary analysis (182 (68%) intensive arm; 197 (75%) standard arm). 84 patients withdrew from the study during the follow-up period (52 intensive arm; 32 standard arm). Mean systolic blood pressure dropped by 16.1 mm Hg to 127.4 mm Hg in the intensive target arm and by 12.8 mm Hg to 129.4 mm Hg in the standard arm (difference between groups 2.9 (95% confidence interval 0.2 to 5.7) mm Hg; P=0.03). Conclusions Aiming for target below 130 mm Hg rather than 140 mm Hg for systolic blood pressure in people with cerebrovascular disease in primary care led to a small additional reduction in blood pressure. Active management of systolic blood pressure in this population using a <140 mm Hg target led to a clinically important reduction in blood pressure. Trial registration Current Controlled Trials ISRCTN29062286. PMID:26919870

  6. The association of resting state heart rate variability and 24-hour blood pressure variability in spinal cord injury.

    PubMed

    Thayer, Julian F; Sollers, John J; Clamor, Annika; Koenig, Julian; Hagglund, Kristofer J

    2016-02-15

    Patients with high cervical complete spinal cord injuries (tetraplegia) sustain damage to the autonomic neural pathways that influence cardiovascular functioning and produce variability in the heart rate (HR) and blood pressure (BP). In non-injured individuals, an inverse relationship exists between resting autonomic control of the heart (as evidenced by HR variability (HRV)) and BP variability (BPV). This study examined the relationship between HRV, BP and BPV in individuals with tetraplegic (n=10) and paraplegic (n=10) spinal cord injuries, and a group of healthy controls (n=14). Resting HRV at baseline and 24-hour ambulatory BP measurements were collected from electrocardiogram measures of each participant. HRV was quantified using time- and frequency-domain measures. The standard deviation of the BP measurements was used as an index of BPV. Multivariate analyses of variance were performed to examine group differences for laboratory-based and 24-h dependent variables. The MANOVAs for HRV parameters (λ(14,50)=.352, p=.010, η(2)=.407) and for BP indices and HR (λ(16,48)=.318, p=.013, η(2)=.436) were significant. Furthermore, in line with existing evidence, we found that vagally mediated HRV was inversely related to BPV in healthy controls. However, this relationship did not hold for the tetraplegia group (ρ<|.42|), and mixed results were found for the paraplegia group (e.g., ρ<|.29| for time domain HRV, ρ>|.65| for low-frequency power). These results support the conclusion that the damage to the spinal sympathetic pathways to the heart found in people with tetraplegia causes a significant disruption in baroreflex control of BP. PMID:26810517

  7. Ocean tide loading effects on 24 hour GPS height estimates and resulting time series

    NASA Astrophysics Data System (ADS)

    Penna, N. T.; Stewart, M. P.

    2003-04-01

    GPS data from continuously operating GPS receivers are usually made available on a daily basis in 24 hour data files, so it is convenient for the user to adopt 24 hour data processing sessions. Time series are often then formed from the discrete 24 hour solutions, used for such applications as crustal deformation monitoring or high quality coordinate determination. When heights are estimated, ocean tide loading is a systematic error source that must be considered. Since the principal ocean tide loading effects have periods close to 12 and 24 hours respectively, it has been suggested from previous works that if models for ocean tide loading are not applied when processing GPS data as 24 hour sessions, at worst a small increase in the variance of the height time series will result. This paper further investigates the effects of ocean tide loading on 24 hour GPS height estimates and resulting time series, by considering a year of both simulated and real data from sites in Australia, at which the ocean tide loading effects differ substantially. The effect of each of the individual constituents is also considered. The role of the tropospheric delay mitigation strategy is addressed, regarding the effect on the height estimates when ocean tide loading effects are modelled or ignored.

  8. [THE INFLUENCE OF CYTOFLAVIN AND CARDIOXIPIN ON THE PARAMETERS OF 24-HOUR ARTERIAL PRESSURE MONITORING IN PATIENTS WITH CHRONIC CEREBRAL CIRCULATION INSUFFICIENCY, ARTERIAL HYPERTENSION AND HYPERCHOLESTEROLEMIA].

    PubMed

    Vodop'ianova, O A; Moiseeva, I Ia; Rodina, O P; Kustikova, I N; Antropova, N V

    2015-01-01

    This comparative study of the influence of cytoflavin and cardioxipin on the parameters of 24-hour arterial pressure monitoring in 56 patients with chronic cerebral circulation insufficiency, arterial hypertension and hypercholesterolemia included 32 women and 24 men aged 42-72 years divided into 3 groups matchedfor the stage of diseases, age, sex, severity of AH, total cholesterol level, and antihypertensive therapy. Patients of group 1 were treated without cytoflavin and cardioxipin. Those in group 2 received daily i/v droplet infusion of 10 mg/kg cardioxipin (20-30 droplets/min). Patients of group 3 were given daily i/v droplet infusion of 10 ml cytoflavin in 200 ml 0.9% sodium chloride solution for 10 days. 24-hour arterial pressure monitoring was used to estimate the influence of the two drugs on systolic and diastolic pressure, its daily rhythm, AP variability and frequency of elevation. The study showed that both therapeutic modalities improved daily AP rhythm as manifested in a significant increase of the number of patients with the dipper rhythm and a decrease in the number of systolic/diastolic non-dipper patients. Moreover cytoflavin significantly decreased the number of systolic over-dippers compared with control group. PMID:26117922

  9. Ambulatory 24-hour cardiac oxygen consumption and blood pressure-heart rate variability: effects of nebivolol and valsartan alone and in combination.

    PubMed

    Izzo, Joseph L; Khan, Safi U; Saleem, Osman; Osmond, Peter J

    2015-07-01

    We compared an angiotensin receptor blocker (valsartan; VAL), a beta-blocker (nebivolol; NEB) and the combination of NEB/VAL with respect to 24-hour myocardial oxygen consumption (determined by 24-hour ambulatory heart rate-central systolic pressure product [ACRPP]) and its components. Subjects with hypertension (systolic blood pressure >140 or diastolic blood pressure >90; n = 26) were studied in a double-blinded, double-dummy, forced-titration, crossover design with 3 random-order experimental periods: VAL 320 mg, NEB 40 mg, and NEB/VAL 320/40 mg daily. After 4 weeks of each drug, ambulatory pulse wave analysis (MobilOGraph) was performed every 20 minutes for 24 hours. All three treatments resulted in nearly identical brachial and central systolic blood pressures. NEB alone or in combination with VAL resulted in lower ACRPP (by 11%-14%; P < .001 each) and heart rate (by 18%-20%; P < .001 each) compared with VAL, but stroke work (ACRPP per beat) was lower with VAL. Relative and adjusted variability (standard deviation and coefficient of variation) of heart rate were also lower with NEB and NEB/VAL than VAL. Results in African Americans, the majority subpopulation, were similar to those of the entire treatment group. We conclude that the rate-slowing effects of NEB cause ambulatory cardiac myocardial oxygen consumption to be lower with NEB monotherapy or NEB/VAL combination therapy than with VAL monotherapy. NEB/VAL is not superior to NEB alone in controlling heart rate, blood pressure, or ACRPP. Heart rate variability but not ACRPP variability is reduced by NEB or the combination NEB/VAL. There is no attenuation of beta-blocker-induced rate-slowing effects of in African Americans. PMID:26116459

  10. Insights about serum sodium behavior after 24 hours of continuous renal replacement therapy

    PubMed Central

    Romano, Thiago Gomes; Martins, Cassia Pimenta Barufi; Mendes, Pedro Vitale; Besen, Bruno Adler Maccagnan Pinheiro; Zampieri, Fernando Godinho; Park, Marcelo

    2016-01-01

    Objective The aim of this study was to investigate the clinical and laboratorial factors associated with serum sodium variation during continuous renal replacement therapy and to assess whether the perfect admixture formula could predict 24-hour sodium variation. Methods Thirty-six continuous renal replacement therapy sessions of 33 patients, in which the affluent prescription was unchanged during the first 24 hours, were retrieved from a prospective collected database and then analyzed. A mixed linear model was performed to investigate the factors associated with large serum sodium variations (≥ 8mEq/L), and a Bland-Altman plot was generated to assess the agreement between the predicted and observed variations. Results In continuous renal replacement therapy 24-hour sessions, SAPS 3 (p = 0.022) and baseline hypernatremia (p = 0.023) were statistically significant predictors of serum sodium variations ≥ 8mEq/L in univariate analysis, but only hypernatremia demonstrated an independent association (β = 0.429, p < 0.001). The perfect admixture formula for sodium prediction at 24 hours demonstrated poor agreement with the observed values. Conclusions Hypernatremia at the time of continuous renal replacement therapy initiation is an important factor associated with clinically significant serum sodium variation. The use of 4% citrate or acid citrate dextrose - formula A 2.2% as anticoagulants was not associated with higher serum sodium variations. A mathematical prediction for the serum sodium concentration after 24 hours was not feasible. PMID:27410407

  11. 24-hour ambulatory blood pressure and renal disease in young subjects with type I diabetes.

    PubMed

    Garg, S K; Chase, H P; Icaza, G; Rothman, R L; Osberg, I; Carmain, J A

    1997-01-01

    Twenty-four hour ambulatory blood pressure (ABP) was evaluated in 150 teenage and young adults with insulin-dependent diabetes mellitus (IDDM) to define high-risk subjects who are likely to develop early diabetic nephropathy. Their age range was 16-28 years with diabetes of 3.5-25.8 years duration. All subjects had office blood pressure (BP) measured, wore an ABP monitor for 24 h, and collected two or more timed urine samples for albumin excretion rates (AERs). Eighty-six subjects had no elevation of AER (< 7.6 micrograms/min), 29 subjects had borderline elevations (7.6-20 micrograms/min), 24 subjects had microalbuminuria (20.1-200 micrograms/min), and 11 had macroalbuminuria (> 200 micrograms/min). Age, gender, duration of diabetes, and single office BP readings were similar in the four groups (p > 0.05, logistic regression). All 24-h ABP parameters were significantly higher in subjects with diabetes having AER values greater than 7.6 micrograms/min when compared with healthy age- and gender-matched nondiabetic controls (p < 0.05, Dunnett's t test). The percent of nighttime systolic and diastolic ABP readings above the 90th percentile of normal for age, gender, and race and the percent of readings in the hypertensive range (> 140/90) were significantly related with AERs (p < 0.01; logistic regression). A higher percentage of ABP values above the 90th percentile for age, gender, and ethnic group or of ABP readings above hypertensive levels (> or = 140/90) are associated with diabetic renal disease. PMID:9334907

  12. The Road Ahead to Continuous 24-Hour Intraocular Pressure Monitoring in Glaucoma

    PubMed Central

    Mansouri, Kaweh

    2014-01-01

    Intraocular pressure (IOP) is the only treatable risk factor for glaucoma. Yet, current glaucoma management usually relies on single IOP measurements during clinic hours despite the fact that IOP is a dynamic parameter with individual rhythms. Single IOP measurements underpin all major clinical guidelines on treatment of glaucoma. Other potentially informative parameters, such as IOP fluctuations and peak IOP, have been neglected, and effects of IOP-lowering interventions on such measures are largely unknown. The search for continuous 24-hour IOP monitoring started over 50 years ago, but only recent technological advances have provided clinician-researchers with devices for continuous IOP monitoring. Herein, we discuss innovative approaches with permanent and temporary devices for 24-hour IOP monitoring, such as a contact lens sensor. Despite being in their infancy, these devices may soon enable clinicians to use 24-hour IOP data to improve glaucoma management and reduce the glaucoma-related burden of disease. PMID:25279129

  13. Microtensile bond strength of resin-resin interfaces after 24-hour and 2-month soaking.

    PubMed

    Leavitt, Curry; Boberick, Kenneth G; Winkler, Sheldon

    2007-01-01

    Evaluate the bond strengths of denture base-repair materials to minimize recurrent failure rate. Use microtensile bond strength (muTBS) testing to evaluate the interfacial bonding strength of 6 commercial denture repair materials after 24-hour and 12-month soaking. Blocks of poly(methyl metacrylate) (PMMA) and Triad were fabricated, fractured, and repaired. Twenty bars (1 x 1 x 30 mm) per group were sectioned from each block parallel to the long axis and approximately 90 degrees to the resin-resin repair interface and stored before muTBS testing in a servo-hydraulic tensile-testing machine. Intact PMMA and Triad bars that had been soaked for 24 hours and 12 months were tested for reference. The 24-hour repair strengths for PMMA ranged from 52% to 84% of original strength. Soaking for 12 months resulted in a 20% decrease in strength for the PMMA control. The 12-month repair strengths for PMMA ranged from 43% to 74% of the 12-month soaked material strength. Triad repair tested 35% of original strength after soaking for 24 hours. Permabond (cyanoacrylate) to PMMA tested 47% of original strength after 24 hours of soaking and 26% of the 12-month soaked material strength. Permabond to Triad tested 30% of original strength after 24 hours of soaking. Permabond and Triad showed a 100% adhesive mode of failure. All other materials tested exhibited either an adhesive mode of failure at the denture base-repair-material interface or a complex cohesive failure within the repair-material interface. The muTBS approach can be used to analyze the resin-resin interface of repaired acrylics. The relatively small standard deviations make the muTBS approach attractive. In this study, muTBS was used to evaluate the repair strength of 6 denture repair materials enabling clinicians to make clinical judgments regarding the strongest repair bond available. PMID:17987865

  14. The Three-Continent, 24-Hour Help Desk: An Academic First?

    ERIC Educational Resources Information Center

    Sykes, Jean

    2002-01-01

    Describes Follow the Sun, a computer help-desk service that takes advantage of time differences around the world to permit four universities (University of Colorado Boulder, Australia's Macquarie and Newcastle universities, and the London School of Economics) to share services and provide 24-hour support to users. (EV)

  15. Oropharyngeal 24-Hour pH Monitoring in Children With Airway-Related Problems

    PubMed Central

    Mesallam, Tamer A.

    2016-01-01

    Objectives Diagnosis and clinical presentation of pediatric laryngopharyngeal reflux (LPR) is still controversial. The aims of this work were to study the possibility of performing 24-hour oropharyngeal pH monitoring for children in the outpatient clinic setup and to explore the results of this test in correlation to airway-related problems. Methods In this descriptive qualitative study, 26 children suffering from airway-related problems were included. Oropharyngeal 24-hour pH monitoring was performed for all subjects in the outpatient clinic setting. The distribution of airway diagnoses among the study group was studied versus the results of the pH monitoring. Results There were 16 males and 10 females participated in the study with a mean age of 6.88 (SD, ±5.77) years. Thirty-five percent of the patients were under the age of 3 years (range, 11 months to 3 years). Eight-five percent of the patients tolerated the pH probe insertion and completed 24-hour of pH recording. Laryngomalacia and subglottic stenosis (SGS) were more frequently reported in the positive LPR patients (77%). Conclusion Oropharyngeal 24-hour pH monitoring can be conducted for children in the outpatient setup even in young age children below 3 years old. Among the positive LPR group, SGS and laryngomalacia were the most commonly reported airway findings. PMID:27090271

  16. Assessing dietary intake in childhood cancer survivors: Food frequency questionnaire versus 24-hour diet recalls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cancer diagnosis and treatment may influence dietary intake. The validity of using self-reported methods to quantify dietary intake has not been evaluated in childhood cancer survivors. We validated total energy intake (EI) reported from Food Frequency Questionnaire (FFQ) and repeated 24-hour diet r...

  17. 24-Hour Access: Responding to Students' Need for Late Library Hours at the University of Denver

    ERIC Educational Resources Information Center

    Sewell, Bethany B.

    2013-01-01

    The University of Denver's Penrose Library saw a substantial increase in use as a result of several new and enhanced services over a six-year period. In turn, longer operating hours and increased staffing for a 24-hours-a-day, five-days-a-week (24 x 5) operating schedule was funded. This case study analyzes student need for longer library hours…

  18. Mood-Dependent Cognitive Change in a Man with Bipolar Disorder Who Cycles Every 24 Hours

    ERIC Educational Resources Information Center

    Lam, Dominic; Mansell, Warren

    2008-01-01

    A case study of a bipolar patient whose mood changes every 24 hours is described to illustrate the changes in cognitive processing and content during different phases of bipolar disorder. The participant completed a battery of questionnaires and tasks on 4 separate occasions: twice when depressed and twice when manic. Depression tended to be…

  19. Urinary electrolyte excretion in 24 hours and blood pressure in the INTERSALT Study. I. Estimates of reliability. The INTERSALT Cooperative Research Group.

    PubMed

    Dyer, A R; Shipley, M; Elliott, P

    1994-05-01

    This is the first of two reports dealing with the reliability of measurements of 24-hour urinary electrolyte excretion and blood pressure and estimates of electrolyte-blood pressure associations in INTERSALT, an international study of the relations of electrolyte excretion and other factors to blood pressure, involving more than 10,000 persons from 52 centers in 32 countries. This first report describes methods for estimating reliability, taking into account age and sex, and provides estimates for several urinary variables, blood pressure, and pulse rate. The second report (Am J Epidemiol 1994; 139:940-51) uses these estimates of reliability and multivariate procedures to correct multiple regression coefficients from regressions of blood pressure on 24-hour urinary sodium and potassium excretion, body mass index, and alcohol intake for "regression dilution bias." Age- and sex-adjusted estimates of reliability were computed from data on 805 INTERSALT participants with repeat measurements. These estimates ranged from 0.37 to 0.40 for 24-hour urinary sodium, from 0.47 to 0.52 for potassium, from 0.32 to 0.36 for the sodium:potassium ratio, from 0.64 to 0.69 for calcium, from 0.59 to 0.65 for creatinine, from 0.49 to 0.57 for urinary volume, from 0.49 to 0.51 for magnesium, from 0.58 to 0.62 for pulse, from 0.69 to 0.74 for systolic blood pressure, and from 0.63 to 0.67 for diastolic blood pressure. In addition, estimates of within- and between-person covariances among electrolytes indicated that about half of the observed covariance for sodium and potassium excretion in a single 24-hour urine collection was due to within-person covariation in excretion. PMID:8166143

  20. [Identification of paroxysmal, transient arrhythmias: Intermittent registration more efficient than the 24-hour Holter monitoring].

    PubMed

    Hendrikx, Tijn; Rosenqvist, Mårten; Sandström, Herbert; Persson, Mats; Hörnsten, Rolf

    2015-01-01

    Many patients suffer from palpitations or dizziness/presyncope. These patients are often referred for Holter ECG (24 hour), although the sensitivity for detecting arrhythmias is low. A new method, short intermittent regular and symptomatic ECG registrations at home, might be a convenient and more sensitive alternative also suitable for primary health care. In this case report we present a patient who had contacted health care several times during a seven year period for paroxysmal palpitations. Routine examination with 24 hour Holter ECG and event recorder did not result in a diagnosis. Using intermittent handheld ECG registration at home, a paroxysmal supraventricular arrhythmia was diagnosed. Further investigation revealed that the patient had a concealed Wolff-Parkinson-White (WPW) syndrome. PMID:25584602

  1. Circadian Polymorphisms in Night Owls, in Bipolars, and in Non-24-Hour Sleep Cycles

    PubMed Central

    Klimecki, Walter T.; Nievergelt, Caroline M.; Rex, Katharine M.; Murray, Sarah S.; Shekhtman, Tatyana; Tranah, Gregory J.; Loving, Richard T.; Lee, Heon-Jeong; Rhee, Min Kyu; Shadan, Farhad F.; Poceta, J. Steven; Jamil, Shazia M.; Kline, Lawrence E.; Kelsoe, John R.

    2014-01-01

    People called night owls habitually have late bedtimes and late times of arising, sometimes suffering a heritable circadian disturbance called delayed sleep phase syndrome (DSPS). Those with DSPS, those with more severe progressively-late non-24-hour sleep-wake cycles, and those with bipolar disorder may share genetic tendencies for slowed or delayed circadian cycles. We searched for polymorphisms associated with DSPS in a case-control study of DSPS research participants and a separate study of Sleep Center patients undergoing polysomnography. In 45 participants, we resequenced portions of 15 circadian genes to identify unknown polymorphisms that might be associated with DSPS, non-24-hour rhythms, or bipolar comorbidities. We then genotyped single nucleotide polymorphisms (SNPs) in both larger samples, using Illumina Golden Gate assays. Associations of SNPs with the DSPS phenotype and with the morningness-eveningness parametric phenotype were computed for both samples, then combined for meta-analyses. Delayed sleep and "eveningness" were inversely associated with loci in circadian genes NFIL3 (rs2482705) and RORC (rs3828057). A group of haplotypes overlapping BHLHE40 was associated with non-24-hour sleep-wake cycles, and less robustly, with delayed sleep and bipolar disorder (e.g., rs34883305, rs34870629, rs74439275, and rs3750275 were associated with n=37, p=4.58E-09, Bonferroni p=2.95E-06). Bright light and melatonin can palliate circadian disorders, and genetics may clarify the underlying circadian photoperiodic mechanisms. After further replication and identification of the causal polymorphisms, these findings may point to future treatments for DSPS, non-24-hour rhythms, and possibly bipolar disorder or depression. PMID:25395965

  2. Recovery of amplitude integrated electroencephalographic background patterns within 24 hours of perinatal asphyxia

    PubMed Central

    van Rooij, L G M; Toet, M; Osredkar, D; van Huffelen, A C; Groenendaal, F; de Vries, L S

    2005-01-01

    Objective: To assess the time course of recovery of severely abnormal initial amplitude integrated electroencephalographic (aEEG) patterns (flat trace (FT), continuous low voltage (CLV), or burst suppression (BS)) in full term asphyxiated neonates, in relation to other neurophysiological and neuroimaging findings and neurodevelopmental outcome. Methods: A total of 190 aEEGs of full term infants were reviewed. The neonates were admitted within 6 hours of birth to the neonatal intensive care unit because of perinatal asphyxia, and aEEG recording was started immediately. In all, 160 infants were included; 65 of these had an initial FT or CLV pattern and 25 an initial BS pattern. Neurodevelopmental outcome was assessed using a full neurological examination and the Griffiths' mental developmental scale. Results: In the FT/CLV group, the background pattern recovered to continuous normal voltage within 24 hours in six of the 65 infants (9%). All six infants survived the neonatal period; one had a severe disability, and five were normal at follow up. In the BS group, the background pattern improved to normal voltage in 12 of the 25 infants (48%) within 24 hours. Of these infants, one died, five survived with moderate to severe disability, two with mild disability, and four were normal. The patients who did not recover within 24 hours either died in the neonatal period or survived with a severe disability. Conclusion: In this study there was a small group of infants who presented with a severely abnormal aEEG background pattern within six hours of birth, but who achieved recovery to a continuous normal background pattern within the first 24 hours. Sixty one percent of these infants survived without, or with a mild, disability. PMID:15846017

  3. Patients in 24-hour home care striving for control and safety

    PubMed Central

    2012-01-01

    Background This article concerns Swedish patients receiving 24-hour home care from health care assistants (HC assistants) employed by the municipality. Home care is a complex interactive process involving the patient, family, HC assistants as well as professional care providers. Previous studies exploring patient perspectives on home care have been based mainly on patient interviews. In contrast, the present study took a broad perspective on patients’ experiences and thoughts by combining field observations on care situations with patient and HC assistant interviews. The aim of the study presented in this article was to promote a new and broadened understanding of patients receiving 24-hour home care by constructing a theoretical model to illuminate their main concern. Methods Field observations and semi-structured interviews were conducted with four patients receiving 24-hour home care and their HC assistants. Grounded theory methodology was used. Results The core process identified was Grasping the lifeline, which describes compensatory processes through which patients strived for control and safe care when experiencing a number of exposed states due to inadequate home care. Patients tried to take control by selecting their own HC assistants and sought safe hands by instructing untrained HC assistants in care procedures. When navigating the care system, the patients maintained contacts with professional care providers and coordinated their own care. When necessary, a devoted HC assistant could take over the navigating role. The results are illuminated in a theoretical model. Conclusions The results accentuate the importance to patients of participating in their own care, especially in the selection of HC assistants. The model illustrates some challenging areas for improvement within the organisation of 24-hour home care, such as personnel continuity and competence, collaboration, and routines for acute care. Furthermore, it may be used as a basis for reflection

  4. Mechanical properties of direct and indirect composites after storage for 24 hours and 10 months

    PubMed Central

    Alves, Paula Barbosa; Brandt, William Cunha; Neves, Ana Christina Claro; Cunha, Leonardo Gonçalves; Silva-Concilio, Lais Regiane

    2013-01-01

    Objective: The objective of this study was to evaluate the diametral tensile strength (DTS) and Knoop hardness (KH) of direct (Filtek Z350-3M/ESPE and Charisma-Heraeus Kulzer) and indirect composites (Sinfony-3M/ESPE and Signum-Heraeus Kulzer) kept in storage for two periods of time, 24 hours and 10 months, in distilled water. Methods: Twenty-five specimens of each material were prepared. DTS (n=10) was tested using a universal testing machine (Versat, model 2000) at a crosshead speed of 1.0 mm/min. KH (n=5) was measured using Knoop micro-hardness (HMV-2000; 50 gf for 15 s). All tests were performed 24 hours after polymerization and after 10 months of storage in distilled water at 37°C. The data were statistically analyzed using Kolmogorov-Smirnov, ANOVA and t-Student (P=.05). Results: Filtek Z350, Sinfony, and Signum showed higher DTS values than Charisma after 24 hours. After storage, Sinfony and Signum showed higher DTS values because the storage did not influence the DTS values of the indirect composites. Filtek Z350 showed higher KH values after 24 hours and after storage than other composites; the storage influenced the KH of all composites except Sinfony. Conclusion: Storage for 10 months did not influence the properties of the indirect composite Sinfony. In general, the indirect composites showed higher DTS values than direct composites, especially after 10 months storage. The direct composite Filtek Z350 obtained the highest KH values regardless of storage. PMID:23407869

  5. Analogue step-by-step DC component eliminator for 24-hour PPG signal monitoring.

    PubMed

    Pilt, Kristjan; Meigas, Kalju; Lass, Jaanus; Rosmann, Mart; Kaik, Jüri

    2007-01-01

    For applications where PPG signal AC component needs to be measured without disturbances in its shape and recorded digitally with high digitalization accuracy, the step-by-step DC component eliminator is developed. This paper describes step-by-step DC component eliminator, which is utilized with analogue comparator and operational amplifier. It allows to record PPG signal without disturbances in its shape in 24-hours PPG signal monitoring system. The experiments with PPG signal have been carried out. PMID:18002130

  6. 24-hour-restraint stress induces long-term depressive-like phenotypes in mice.

    PubMed

    Chu, Xixia; Zhou, Ying; Hu, Zhiqiang; Lou, Jingyu; Song, Wei; Li, Jing; Liang, Xiao; Chen, Chen; Wang, Shuai; Yang, Beimeng; Chen, Lei; Zhang, Xu; Song, Jinjing; Dong, Yujie; Chen, Shiqing; He, Lin; Xie, Qingguo; Chen, Xiaoping; Li, Weidong

    2016-01-01

    There is an increasing risk of mental disorders, such as acute stress disorder (ASD), post-traumatic stress disorder (PTSD) and depression among survivors who were trapped in rubble during earthquake. Such long-term impaction of a single acute restraint stress has not been extensively explored. In this study, we subjected mice to 24-hour-restraint to simulate the trapping episode, and investigated the acute (2 days after the restraint) and long-term (35 days after the restraint) impacts. Surprisingly, we found that the mice displayed depression-like behaviors, decreased glucose uptake in brain and reduced adult hippocampal neurogenesis 35 days after the restraint. Differential expression profiling based on microarrays suggested that genes and pathways related to depression and other mental disorders were differentially expressed in both PFC and hippocampus. Furthermore, the depression-like phenotypes induced by 24-hour-restraint could be reversed by fluoxetine, a type of antidepressant drug. These findings demonstrated that a single severe stressful event could produce long-term depressive-like phenotypes. Moreover, the 24-hour-restraint stress mice could also be used for further studies on mood disorders. PMID:27609090

  7. 24-hour-restraint stress induces long-term depressive-like phenotypes in mice

    PubMed Central

    Zhou, Ying; Hu, Zhiqiang; Lou, Jingyu; Song, Wei; Li, Jing; Liang, Xiao; Chen, Chen; Wang, Shuai; Yang, Beimeng; Chen, Lei; Zhang, Xu; Song, Jinjing; Dong, Yujie; Chen, Shiqing; He, Lin; Xie, Qingguo; Chen, Xiaoping; Li, Weidong

    2016-01-01

    There is an increasing risk of mental disorders, such as acute stress disorder (ASD), post-traumatic stress disorder (PTSD) and depression among survivors who were trapped in rubble during earthquake. Such long-term impaction of a single acute restraint stress has not been extensively explored. In this study, we subjected mice to 24-hour-restraint to simulate the trapping episode, and investigated the acute (2 days after the restraint) and long-term (35 days after the restraint) impacts. Surprisingly, we found that the mice displayed depression-like behaviors, decreased glucose uptake in brain and reduced adult hippocampal neurogenesis 35 days after the restraint. Differential expression profiling based on microarrays suggested that genes and pathways related to depression and other mental disorders were differentially expressed in both PFC and hippocampus. Furthermore, the depression-like phenotypes induced by 24-hour-restraint could be reversed by fluoxetine, a type of antidepressant drug. These findings demonstrated that a single severe stressful event could produce long-term depressive-like phenotypes. Moreover, the 24-hour-restraint stress mice could also be used for further studies on mood disorders. PMID:27609090

  8. A New Method to Make 24-Hour Urine Collection More Convenient: A Validity Study

    PubMed Central

    2014-01-01

    Background and Objectives. This study proposes a novel urine collection device that can divide each urine collection into 20 parts and store and cool just one part. The aim of the current study is to compare measured biomarkers from the proposed urine collection device to those of conventional 24-hour sampling method. We also hypothesized that the new method would significantly increase patients' adherence to the timed urine collection. Methods. Two 24-hour urine samples with the conventional method and with the new automated urine collection device that uses just one-twentieth of each void were obtained from 40 healthy volunteers. Urine parameters including volume, creatinine, and protein levels were compared between the two methods and the agreement of two measurements for each subject was reported through Bland-Altman plots. Results. Our results confirmed that for all three variables, there is a positive correlation (P < 0.001) between the two measurements and high degree of agreement could be seen in Bland-Altman plots. Moreover, more subjects reported the new method as “more convenient” for 24-hour urine collection. Conclusions. Our results clearly indicate that a fixed proportion of each void may significantly reduce the urine volume in timed collections and this, in turn, may increase subjects' adherence to this difficult sampling. PMID:24963405

  9. Phase II trial of cyclophosphamide, leucovorin, 5-fluorouracil 24-hour infusion and tamoxifen in pancreatic cancer.

    PubMed

    Eckel, F; Lersch, C; Lippl, F; Assmann, G; Schulte-Frohlinde, E

    2000-09-01

    Leucovorin modulates the cytotoxic effects of 5-fluorouracil (5-FU) in the treatment of cancer. 24-hour infusion of 5-FU has been shown to enhance antitumor activity in colorectal cancer compared to bolus infusion. According to experimental data cyclophosphamide and tamoxifen may enhance the effectiveness of leucovorin and 5-FU. A phase II trial was initiated to evaluate the effect of a combination of low-dose cyclophosphamide (C), leucovorin (L), 5-FU (F) and tamoxifen (T) (CLFT) in advanced pancreatic cancer. Fifty patients were treated monthly with 300 mg/m2 cyclophosphamide and weekly with 500 mg/m2 leucovorin followed by a 24-hour infusion of 2000 mg/m2 5-FU and tamoxifen 20 mg bid. Three patients had a partial response (6%), two a minor response (4%) and 32 (64%) no change of disease. The median survival time was 8.5 months for all patients, the median time to progression of disease was 4.6 months and the 1-year survival rate was 28%. CLFT was fairly well tolerated. These data suggest that biochemical modulation of 24-hour infusional 5-FU with leucovorin together with cyclophosphamide and tamoxifen has some positive effects in the treatment of pancreatic cancer. PMID:11144522

  10. [Formula creatinine clearance as a substitute for 24-hour creatine clearance in children with kidney transplantation].

    PubMed

    Aufricht, C; Balbisi, A; Gerdov, C; Müller, T; Lothaller, M A; Balzar, E

    1995-01-01

    Despite many theoretical advantages, formula-creatininclearance (Schwartz et al, Journal of Pediatrics 1976) has not found broad clinical acceptance in everyday pediatric patient care. In this study we report our results of long term observations (11.7 +/- 6.8 (1.7-24.8) months) of measured and computed creatininclearance in 27 children after renal transplantation (15 boys, 12 girls, mean age 14.5 +/- 4.2 (5.5-20) years) at the Kinderdialyse of the Universitäts-Kinderklinik of Vienna. We found a wide scattered correlation between the measured and computed creatininclearance values with a 90% confidence interval between -30% to +60% of the 24 hour creatininclearance. Formula creatininclearance (SD 17.8%) was markedly better reproducable than the 24 hour creatininclearancethe (SD 37.8%), the intraindividuell collecting error (36.1%) was almost twice the interindividuell "coefficient" error (20.27%). We therefore conclude that the 24 hour creatininclearance is by far not as accurate as the complexity of the procedure pretends and support broad clinical acceptance for the formula creatininclearance. PMID:7752601

  11. Impact of diet on 24-hour intragastric pH profile in healthy horses.

    PubMed

    Damkel, Cornelia; Snyder, Alice; Uhlig, Albrecht; Coenen, Manfred; Schusser, Gerald Fritz

    2015-01-01

    An electrode incorporated into a polyethylene hose was introduced under endoscopic control into the stomach of six fasting adult horses for long-lasting pH measurements. The intragastric pH was recorded every four seconds for a period of 24 hours. The Warmblood horses were assigned randomly to receive hay ad libitum (H group); 1.5 kg hay/100 kg BW/day and 1 kg concentrate/100 kg BW/ day (C group) or protocol C plus 75 g pectin-lecithin supplement/100 kg BW/day (P group). The horses were adapted to each diet for 14 days. The 24-hour median pH value for protocol H (2.69) was significantly lower compared to protocol C (3.35) and P (3.44) (p < 0.05). The horses in protocol P had a significant higher percentage (40.1 %) of 24-hour intragastric pH values ≥ 4 than in protocol C (36.2 %) or in protocol H (25.3 %) (p < 0.05). PMID:26591378

  12. Factors Associated With High Sodium Intake Based on Estimated 24-Hour Urinary Sodium Excretion

    PubMed Central

    Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

    2016-01-01

    Abstract Although reducing dietary salt consumption is the most cost-effective strategy for preventing progression of cardiovascular and renal disease, policy-based approaches to monitor sodium intake accurately and the understanding factors associated with excessive sodium intake for the improvement of public health are lacking. We investigated factors associated with high sodium intake based on the estimated 24-hour urinary sodium excretion, using data from the 2009 to 2011 Korea National Health and Nutrition Examination Survey (KNHANES). Among 21,199 adults (≥19 years of age) who participated in the 2009 to 2011 KNHANES, 18,000 participants (weighted n = 33,969,783) who completed urinary sodium and creatinine evaluations were analyzed in this study. The 24-hour urinary sodium excretion was estimated using Tanaka equation. The mean estimated 24-hour urinary sodium excretion level was 4349 (4286–4413) mg per day. Only 18.5% (weighted n = 6,298,481/3,396,973, unweighted n = 2898/18,000) of the study participants consumed less the 2000 mg sodium per day. Female gender (P < 0.001), older age (P < 0.001), total energy intake ≥50 percentile (P < 0.005), and obesity (P < 0.001) were associated with high sodium intake, even after adjusting for potential confounders. Senior high school/college graduation in education and managers/professionals in occupation were associated with lower sodium intake (P < 0.001). According to hypertension management status, those who had hypertension without medication consumed more sodium than those who were normotensive. However, those who receiving treatment for hypertension consumed less sodium than those who were normotensive (P < 0.001). The number of family members, household income, and alcohol drinking did not affect 24-hour urinary sodium excretion. The logistic regression analysis for the highest estimated 24-hour urinary sodium excretion quartile (>6033 mg/day) using the

  13. 77 FR 65310 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-26

    ... the 2006 24-hour Fine Particle (PM 2.5 ) National Ambient Air Quality Standards,'' 74 FR 58688... Federal Regulations DC District of Columbia EO Executive Order EPA Environmental Protection Agency FR... EPA finalized designations for the 2006 24-hour PM 2.5 NAAQS (74 FR 58688, November 13, 2009), the...

  14. 40 CFR 52.1990 - Interstate Transport for the 2006 24-hour PM2.5 NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Interstate Transport for the 2006 24-hour PM2.5 NAAQS. 52.1990 Section 52.1990 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1990 Interstate Transport for the 2006 24-hour PM2.5 NAAQS. (a) EPA approves the portion of...

  15. 40 CFR 52.1990 - Interstate Transport for the 2006 24-hour PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Interstate Transport for the 2006 24-hour PM2.5 NAAQS. 52.1990 Section 52.1990 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1990 Interstate Transport for the 2006 24-hour PM2.5 NAAQS. (a) EPA approves the portion of...

  16. 40 CFR 52.1990 - Interstate Transport for the 2006 24-hour PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Interstate Transport for the 2006 24-hour PM2.5 NAAQS. 52.1990 Section 52.1990 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1990 Interstate Transport for the 2006 24-hour PM2.5 NAAQS. (a) EPA approves the portion of...

  17. Tasimelteon for the treatment of non-24-hour sleep-wake disorder.

    PubMed

    Neubauer, D N

    2015-01-01

    Tasimelteon (Hetlioz®), a melatonin receptor agonist, is the first, and, at the time of the publication, the only drug to be approved by the U.S. Food and Drug Administration (FDA) for the treatment of non-24-hour sleep-wake disorder (non-24). This circadian rhythm disorder occurs most commonly in blind individuals without light perception, and it results from their inability to entrain to the 24-hour photoperiod, although the indication does not specify a particular patient population. Non-24 is characterized by a persistent cycle of nighttime insomnia and daytime sleepiness, alternating with asymptomatic periods depending on an individual's degree of circadian rhythm synchronization with the photoperiod at any particular time. Phase II clinical trials in healthy individuals confirmed the circadian phase-shifting potential of tasimelteon. Phase III trials in totally blind subjects diagnosed with non-24 demonstrated the efficacy of tasimelteon in reducing both nighttime wakefulness and daytime napping. Physiologic monitoring revealed that tasimelteon resulted in a higher proportion of individuals becoming entrained to the 24-hour cycle compared with placebo. Safety assessments indicated that tasimelteon is well tolerated, with the most common adverse events being headache, alanine aminotransferase elevation, nightmares or unusual dreams, and upper respiratory or urinary tract infections. Tasimelteon is available as a capsule in a single 20-mg dose and it must be obtained through Vanda Pharmaceutical's HetliozSolutions program with dispensing through a specialty pharmacy. Safety studies in blind individuals diagnosed with non-24 are ongoing and a future clinical trial with Smith-Magenis syndrome patients is planned. PMID:25685859

  18. 24-Hour Measurement of Gastric pH in Rural South Africa

    PubMed Central

    Sammon, Alastair M.; Ndebia, Eugene J.; Umapathy, Ekambaram; Iputo, Jehu E.

    2015-01-01

    Background. Previous studies have established norms of 24-hour gastric pH profiles for western countries. This study was designed to establish the pattern for a rural African population with a high incidence of oesophageal cancer. Methods. After lower oesophageal manometry a probe was placed 10 cm distal to the lower oesophageal sphincter. We carried out 24-hour ambulatory monitoring of gastric pH on 59 healthy subjects. This was satisfactorily completed on 26 female and 18 male (age 21–64, median 35) subjects in the Transkei region of South Africa. Results. The mean 24 hour gastric pH was 2.84 and the mean night-time pH was 3.7. 40 volunteers recorded a night-time pH reaching over 4. 33 volunteers recorded a night-time pH over 7. Night-time alkalinisation was present for 136.4 minutes (25th centile 22.8, 75th centile 208.1) at pH4 or over, and 79.3 (2.5, 122.7) minutes at pH7 or over. Episodes of rapid alkaline rise were 17 (10, 47). 21.1% of these occurred while supine. 35 of 36 tested subjects were positive for H. pylori IgG. Conclusion. Gastric alkalinisation is common in Transkei, at a higher pH than that reported in other studies, and is sustained longer. Nighttime alkalinisation is frequent. This suggests a high level of duodenogastric reflux. PMID:25861260

  19. Bioenergetical and Cardiac Adaptations of Pilots to a 24-Hour Team Kart Race.

    PubMed

    Durand, Sylvain; Ripamonti, Michael; Rahmani, Abderrahmane; Beaune, Bruno

    2015-11-01

    This study aimed to evaluate energy expenditure (EE) and heart rate (HR) response in kart pilots to successive driving bouts during a 24-hour team race. Eight adult male pilots (22.8 ± 4.1 years) participated to a team 24-hour speedway kart race in Le Mans (France). They alternatively piloted a 390 cm kart. Each relay was 45 minutes long and each pilot performed 4 relays. For each pilot, mean speeds were calculated from lap-to-lap duration recordings using a telemetric infrared timing device. Heart rate values were recorded continuously on 5-second intervals using a portable cardiometric device. Total energy expenditure (EET) and physical activity ratio (PAR) were determined by accelerometry. To pilot a kart during 45 minutes at a mean speed around 62 km·h induces a 300-kcal EET, corresponding to a 5.6-Mets PAR. This effort is responsive for a 73 b·min increase in HR, from 84.1 ± 7.6 to 157.4 ± 11.0 b·min (82% maximal heart rate intensity). However, during this relay period, HR values seemed independent to mean speed performance and bioenergetical values. Thus, in the context of the 24-hour team race, the variability in effort made during each relay and relay succession did not alter bioenergetical adaptation of pilots to kart driving. The high EE and HR values would be better explained by both emotional stress and environmental constraints such as speedway configuration and vibrations. The way how these factors specifically influence bioenergetical demand, and their relative importance, has to be specified to optimize training procedure and recommendations. PMID:25029011

  20. Evaluation of Intradermal and Subcutaneous Infusion Set Performance Under 24-Hour Basal and Bolus Conditions

    PubMed Central

    McVey, Elaine; Keith, Steven; Herr, Joshua K.; Sutter, Diane; Pettis, Ronald J.

    2015-01-01

    Background: This study sought to assess the function and delivery reliability of intradermal (ID) infusion sets used with commercial insulin pumps. Method: Healthy subjects (n = 43) were randomized to either ID or subcutaneous (SC) arms, and received basal/bolus placebo delivery for 24 hours. Subjects received 4 of 8 infusion set combinations (ID: microneedle design A or B, with 2 pump brands [Animas or MiniMed]; SC: Teflon Quickset or steel Rapid-D, Animas pump only, with or without overtaping) and were evaluated for pump occlusion alarms, fluid leakage, pain, and tissue tolerability. A novel algorithm was developed to determine flow consistency based on fluid pressure, and the duration and occurrence rate for periods of unalarmed but interrupted flow (“silent occlusions’”) were compared. Results: ID delivery was successfully maintained over the 24-hour infusion period. The number of silent occlusions was lower for ID microneedle cannula design B than A (P < .01) and lower for Rapid-D SC device compared to Quick-set (P = .03). There was no significant difference in the number of occlusion alarms between the ID and SC devices with the Animas pump. However, the pumps tested with ID devices had significantly different alarm rates (MiniMed 29.5%, Animas 0%, P < .001). Leakage and tissue tolerability were comparable across devices. Conclusion: The ID infusion set reliably delivered diluent for an extended 24-hour period in healthy subjects and was well tolerated. Silent occlusion flow interruptions could be detected in both ID and SC infusion sets using a proprietary algorithm. This algorithm is a promising method for quantitatively evaluating infusion set flow performance. PMID:26319228

  1. Implementation of a 24-Hour Pharmacy Service with Prospective Medication Review in the Emergency Department

    PubMed Central

    Yee, Linda; Claudio-Saez, Maria; Halim, Qazi; Marshall, Lewis; Hayes-Quinn, Mary

    2015-01-01

    Background: It is reported that more than 128 million patients are seen in emergency departments (EDs) annually. Patient overcrowding had been associated with an increased occurrence of medication errors. Purpose: Due to increased patient volume and the need for improved patient safety, a 24-hour pharmacy service was established for our institution’s ED. The purpose of the study is to quantify and demonstrate the impact of a 24-hour pharmacy service in an urban ED. Methods: This was a retrospective descriptive study conducted at a regional level 1 trauma center. The study period occurred between December 2012 and July 2013. The following variables were quantified and analyzed: number of medication orders reviewed, number of intravenous medications compounded, and number of clinical interventions that were recommended by the ED pharmacy team (EDPT) and accepted by ED clinicians. Results: A total of 3,779 medication orders were reviewed by the EDPT. Of these orders, 3,482 (92%) were prospectively reviewed. A total of 3,068 (81.2%) and 711 (18.8%) orders were reviewed for the adult and pediatric ED, respectively. During the study period, the EDPT procured 549 intravenous admixtures and conducted 642 clinical interventions. Most of the interventions involved providing drug information for physicians and nurses (45.9%), adjusting drug dosages (21.1%), and recommending antimicrobial therapy (15.1%). Conclusion: The implementation of a 24-hour pharmacy service at our institution was an innovative practice that increased the role of pharmacists in the ED. The EDPT conducted prospective medication review, procured intravenous admixtures from a sterile environment, and provided therapeutic recommendations for the ED interdisciplinary team. PMID:25717209

  2. Treating allergic conjunctivitis: A once-daily medication that provides 24-hour symptom relief

    PubMed Central

    Schaeffer, Jack; Donnenfeld, Eric

    2016-01-01

    Background: Allergic conjunctivitis (AC) is a common ocular inflammatory manifestation of allergen exposure in sensitized individuals. Signs and symptoms of AC can decrease quality of life, interfere with productivity, and lead to considerable economic burden. Consistent suppression of conjunctival inflammation is necessary for managing AC, but currently available medications require frequent administration and exhibit limited duration of action. Methods: In this review, we summarized AC pathogenesis, diagnosis, and current treatment options as well as their limitations. Findings from the literature were discussed in the context of the unmet need for a once-daily medication with sustained 24-hour effectiveness. Results: Topical pharmacologic treatments are the most common approach for managing extant AC; however, most available medications require multiple daily instillations. Dual-acting antihistamine-mast cell stabilizing agents are currently considered first-line therapeutics for AC because they provide acute relief of signs and symptoms and block persistent inflammation to promote regression of AC. Recent studies of a newly-developed, higher-concentration formulation of a dual-acting antihistamine-mast cell stabilizer have demonstrated that this formulation provides a 24-hour duration of action with once-daily dosing. Conclusions: Dual-acting AC medications exhibit a high degree of overall effectiveness and are well tolerated for chronic use. A newly available once-daily medication that manages signs and symptoms of AC for a full 24 hours may be considered a treatment of choice for patients experiencing seasonal or perennial AC. ClinicalTrials.gov NCT01743027 and NCT01479374 PMID:27466061

  3. Comparison of observation level versus 24-hour average atmospheric loading corrections in VLBI analysis

    NASA Astrophysics Data System (ADS)

    MacMillan, D. S.; van Dam, T. M.

    2009-04-01

    Variations in the horizontal distribution of atmospheric mass induce displacements of the Earth's surface. Theoretical estimates of the amplitude of the surface displacement indicate that the predicted surface displacement is often large enough to be detected by current geodetic techniques. In fact, the effects of atmospheric pressure loading have been detected in Global Positioning System (GPS) coordinate time series [van Dam et al., 1994; Dong et al., 2002; Scherneck et al., 2003; Zerbini et al., 2004] and very long baseline interferometery (VLBI) coordinates [Rabble and Schuh, 1986; Manabe et al., 1991; van Dam and Herring, 1994; Schuh et al., 2003; MacMillan and Gipson, 1994; and Petrov and Boy, 2004]. Some of these studies applied the atmospheric displacement at the observation level and in other studies, the predicted atmospheric and observed geodetic surface displacements have been averaged over 24 hours. A direct comparison of observation level and 24 hour corrections has not been carried out for VLBI to determine if one or the other approach is superior. In this presentation, we address the following questions: 1) Is it better to correct geodetic data at the observation level rather than applying corrections averaged over 24 hours to estimated geodetic coordinates a posteriori? 2) At the sub-daily periods, the atmospheric mass signal is composed of two components: a tidal component and a non-tidal component. If observation level corrections reduce the scatter of VLBI data more than a posteriori correction, is it sufficient to only model the atmospheric tides or must the entire atmospheric load signal be incorporated into the corrections? 3) When solutions from different geodetic techniques (or analysis centers within a technique) are combined (e.g., for ITRF2008), not all solutions may have applied atmospheric loading corrections. Are any systematic effects on the estimated TRF introduced when atmospheric loading is applied?

  4. Pulse wave velocity 24-hour monitoring with one-site measurements by oscillometry

    PubMed Central

    Posokhov, Igor N

    2013-01-01

    This review describes issues for the estimation of pulse wave velocity (PWV) under ambulatory conditions using oscillometric systems. The difference between the principles of measuring the PWV by the standard method and by oscillometry is shown, and information on device validation studies is summarized. It was concluded that currently oscillometry is a method that is very convenient to use in the 24-hour monitoring of the PWV, is relatively accurate, and is reasonably comfortable for the patient. Several indices with the same principles as those in the analysis of blood pressure in ambulatory monitoring of blood pressure, namely the assessment of load, variability, and circadian rhythm, are proposed. PMID:23549868

  5. [Program for early detection of illness level in foals during the first 24 hours of life].

    PubMed

    Bostedt, H; Hospes, R; Herfen, K

    1997-11-01

    Basing on exact investigations of normal behaviour and abnormalities in newborn and up to 24 hours old foals a program for evaluation, comprehending exogeniously judgable criteria, was developed. It aims at a quick recognition of aberrations in behaviour. The program includes a score, which allows early diagnosis of even subtile abnormalities. As a result, a veterinary surgeon should be consulted if the score exposes a critical situation, so that therapy can be started in time. Furthermore informations about investigations on blood-glucose- and immunoglobulin-G-concentration in relation to neonatal foal diseases are given. PMID:9451764

  6. Intermittent short ECG recording is more effective than 24-hour Holter ECG in detection of arrhythmias

    PubMed Central

    2014-01-01

    Background Many patients report symptoms of palpitations or dizziness/presyncope. These patients are often referred for 24-hour Holter ECG, although the sensitivity for detecting relevant arrhythmias is comparatively low. Intermittent short ECG recording over a longer time period might be a convenient and more sensitive alternative. The objective of this study is to compare the efficacy of 24-hour Holter ECG with intermittent short ECG recording over four weeks to detect relevant arrhythmias in patients with palpitations or dizziness/presyncope. Methods Design: prospective, observational, cross-sectional study. Setting: Clinical Physiology, University Hospital. Patients: 108 consecutive patients referred for ambiguous palpitations or dizziness/presyncope. Interventions: All individuals underwent a 24-hour Holter ECG and additionally registered 30-second handheld ECG (Zenicor EKG® thumb) recordings at home, twice daily and when having cardiac symptoms, during 28 days. Main outcome measures: Significant arrhythmias: atrial fibrillation (AF), paroxysmal supraventricular tachycardia (PSVT), atrioventricular (AV) block II–III, sinus arrest (SA), wide complex tachycardia (WCT). Results 95 patients, 42 men and 53 women with a mean age of 54.1 years, completed registrations. Analysis of Holter registrations showed atrial fibrillation (AF) in two patients and atrioventricular (AV) block II in one patient (= 3.2% relevant arrhythmias [95% CI 1.1–8.9]). Intermittent handheld ECG detected nine patients with AF, three with paroxysmal supraventricular tachycardia (PSVT) and one with AV-block-II (= 13.7% relevant arrhythmias [95% CI 8.2–22.0]). There was a significant difference between the two methods in favour of intermittent ECG with regard to the ability to detect relevant arrhythmias (P = 0.0094). With Holter ECG, no symptoms were registered during any of the detected arrhythmias. With intermittent ECG, symptoms were registered during half of the arrhythmia

  7. Assessing Dietary Intake in Childhood Cancer Survivors: Food Frequency Questionnaire Versus 24-Hour Diet Recalls.

    PubMed

    Zhang, Fang Fang; Roberts, Susan B; Must, Aviva; Wong, William W; Gilhooly, Cheryl H; Kelly, Michael J; Parsons, Susan K; Saltzman, Edward

    2015-10-01

    Cancer diagnosis and treatment may influence dietary intake. The validity of using self-reported methods to quantify dietary intake has not been evaluated in childhood cancer survivors. We validated total energy intake (EI) reported from Food Frequency Questionnaire (FFQ) and repeated 24-hour diet recalls (24HRs) against total energy expenditure (TEE) measured using the doubly labeled water method in 16 childhood cancer survivors. Dietary underreporting, assessed by (EI-TEE)/TEE × 100%, was 22% for FFQ and 1% for repeated 24HRs. FFQ significantly underestimates dietary intake and should not be used to assess the absolute intake of foods and nutrients in childhood cancer survivors. PMID:25883059

  8. The Application of a Contact Lens Sensor in Detecting 24-Hour Intraocular Pressure-Related Patterns

    PubMed Central

    2016-01-01

    Glaucoma is one of the leading causes of blindness worldwide. Recent studies suggest that intraocular pressure (IOP) fluctuations, peaks, and rhythm are important factors in disease advancement. Yet, current glaucoma management remains hinged on single IOP measurements during clinic hours. To overcome this limitation, 24-hour IOP monitoring devices have been employed and include self-tonometry, permanent IOP, and temporary IOP monitoring. This review discusses each IOP measuring strategy and focuses on the recently FDA-approved contact lens sensor (CLS). The CLS records IOP-related ocular patterns for 24 hours continuously. Using the CLS, IOP-related parameters have been found to be associated with the rate of visual field progression in primary open-angle glaucoma, disease progression in primary angle-closure glaucoma, and various clinical variables in ocular hypertension. The CLS has been used to quantify blink rate and limbal strain and measure the circadian rhythm in a variety of disease states including normal-tension glaucoma and thyroid eye disease. The effects of various IOP-lowering interventions were also characterized using the CLS. CLS provides a unique, safe, and well-tolerated way to study IOP-related patterns in a wide range of disease states. IOP-related patterns may help identify patients most at risk for disease progression and assist with the development of tailored treatments. PMID:27525110

  9. Comparison of 3 different anesthetic techniques on 24-hour recovery after otologic surgical procedures.

    PubMed

    Jellish, W S; Leonetti, J P; Fahey, K; Fury, P

    1999-03-01

    Intravenous propofol anesthesia is better than inhalational anesthesia for otologic surgery, but cost and intraoperative movement make this technique prohibitive. This study compares a propofol sandwich anesthetic with a total propofol or inhalational anesthetic for otologic surgery to determine which produces the best perioperative conditions and least expense. One hundred twenty patients undergoing ear surgery were randomly chosen to receive an anesthetic with either isoflurane (INHAL), total propofol (TPROP), or propofol used in conjunction with isoflurane (PSAND). Postoperative wakeup and the incidence and severity of nausea, vomiting, and pain were compared among groups. Antiemetic administration and discharge times from recovery and the hospital were also compared. The groups were similar, but anesthesia times were longer in the INHAL group. Emergence from anesthesia after PSAND or TPROP was more rapid than after INHAL. Recovery during the next 24 hours was associated with less nausea and vomiting with PSAND than with INHAL. The cost of the PSAND anesthetic was similar to that of INHAL, and both were less than TPROP. PSAND anesthesia may be similar to TPROP and better than INHAL for otologic procedures. PSAND was less expensive than TPROP and produced a similar recovery profile and antiemetic effect in the 24-hour period after surgery. PMID:10064647

  10. Regional Neurodegeneration and Gliosis Are Amplified by Mild Traumatic Brain Injury Repeated at 24-Hour Intervals

    PubMed Central

    Bolton, Amanda Nicholle; Saatman, Kathryn Eileen

    2014-01-01

    Most traumatic brain injuries (TBIs) that occur every year are classified as ‘mild’. Individuals involved in high-risk activities may sustain multiple mild TBIs. We evaluated the acute physiological and histopathological consequences of mild TBI in a mouse model, comparing sham injury, single impact, or 5 impacts at a 24- or 48-hour inter-injury interval. A single closed skull impact resulted in bilateral gliosis in the hippocampus and entorhinal cortex that was proportional to impact depth. Midline impact, at a depth just above the threshold to induce transient unconsciousness, produced occasional axonal injury and degenerating neurons accompanied by astrogliosis in the entorhinal cortex and cerebellum. Mild TBI repeated every 24 hours resulted in bilateral hemorrhagic lesions in the entorhinal cortex along with significantly increased neurodegeneration and microglial activation despite diminished durations of apnea and unconsciousness with subsequent impacts. Astrogliosis and diffusely distributed axonal injury were also observed bilaterally in the cerebellum and the brainstem. When the interval between mild TBIs was increased to 48 hours, the pathological consequences were comparable to a single TBI. Together, these data suggest that in mice the brain remains at increased risk for damage for 24 hours after mild TBI despite reduced acute physiological responses to subsequent mild impacts. PMID:25232942

  11. Sleep in healthy elderly subjects: a 24-hour ambulatory polysomnographic study.

    PubMed

    Gigli, G L; Placidi, F; Diomedi, M; Maschio, M; Silvestri, G; Scalise, A; Marciani, M G

    1996-04-01

    It is still debated whether the deterioration of the sleep pattern, frequently reported by elderly subjects, is due only to aging per se. Other factors associated with aging or modifications of biological rhythms could also be involved. Elderly subjects frequently complain of daytime sleepiness, but it is not clear whether this actually represents a return to a polyphasic structure of sleep, or only a consequence of a disturbed night sleep. Ten healthy, independent and active elderly subjects (age > 72 years) were elevated by means of 24-hour ambulatory polysomnography. Findings of nocturnal sleep were compared with sleep of the same group in the 24-hour period and with sleep of young healthy controls. We observed a fragmentation of nocturnal sleep, but a fairly good representation of stages and a preservation of cyclicity. Except for three cases, with early or late times of sleep onset and wake-up, sleep disruption did not seem to be related to modification of circadian rhythms. Only three subjects presented undesired daytime naps, whereas the others either did not show daytime sleep at all, or were used to having their siesta after lunch since their young adulthood. In normal aging, daytime sleep does not constitute a social problem. Ambulatory polysomnography is a valid alternative to laboratory recordings in the identification of daytime sleep. PMID:8734563

  12. Deviation of innate circadian period from 24 hours reduces longevity in mice

    PubMed Central

    Libert, Sergiy; Bonkowski, Michael S.; Pointer, Kelli; Pletcher, Scott D.; Guarente, Leonard

    2012-01-01

    Summary The variation of individual lifespans, even in highly inbred cohorts of animals and under strictly controlled environmental conditions, is substantial and not well understood. This variation in part could be due to epigenetic variation, which later affects the animal’s physiology and ultimately longevity. Identification of the physiological properties that impact health and lifespan is crucial for longevity research and the development of anti-aging therapies. Here we measured individual circadian and metabolic characteristics in a cohort of inbred F1 hybrid mice and correlated these parameters to their lifespans. We found that mice with innate circadian periods close to 24 hours (revealed during 30 days of housing in total darkness) enjoyed nearly 20% longer lifespans than their littermates, which had shorter or longer innate circadian periods. These findings show that maintenance of a 24 hour intrinsic circadian period is a positive predictor of longevity. Our data suggest that circadian period may be used to predict individual longevity and that processes that control innate circadian period affect aging. PMID:22702406

  13. The Application of a Contact Lens Sensor in Detecting 24-Hour Intraocular Pressure-Related Patterns.

    PubMed

    Xu, Sarah C; Gauthier, Angela C; Liu, Ji

    2016-01-01

    Glaucoma is one of the leading causes of blindness worldwide. Recent studies suggest that intraocular pressure (IOP) fluctuations, peaks, and rhythm are important factors in disease advancement. Yet, current glaucoma management remains hinged on single IOP measurements during clinic hours. To overcome this limitation, 24-hour IOP monitoring devices have been employed and include self-tonometry, permanent IOP, and temporary IOP monitoring. This review discusses each IOP measuring strategy and focuses on the recently FDA-approved contact lens sensor (CLS). The CLS records IOP-related ocular patterns for 24 hours continuously. Using the CLS, IOP-related parameters have been found to be associated with the rate of visual field progression in primary open-angle glaucoma, disease progression in primary angle-closure glaucoma, and various clinical variables in ocular hypertension. The CLS has been used to quantify blink rate and limbal strain and measure the circadian rhythm in a variety of disease states including normal-tension glaucoma and thyroid eye disease. The effects of various IOP-lowering interventions were also characterized using the CLS. CLS provides a unique, safe, and well-tolerated way to study IOP-related patterns in a wide range of disease states. IOP-related patterns may help identify patients most at risk for disease progression and assist with the development of tailored treatments. PMID:27525110

  14. A Compute Perspective: Delivering Decision Support Products in 24 Hours from the Airborne Snow Observatory

    NASA Astrophysics Data System (ADS)

    Ramirez, P.; Mattmann, C. A.; Painter, T. H.; Seidel, F. C.; Trangsrud, A.; Hart, A. F.; Goodale, C. E.; Boardman, J. W.; Heneghan, C.; Verma, R.; Khudikyan, S.; Boustani, M.; Zimdars, P. A.; Horn, J.; Neely, S.

    2013-12-01

    The JPL Airborne Snow Observatory (ASO) must process 100s of GB of raw data to 100s of Terabytes of derived data in 24 hour Near Real Time (NRT) latency in a geographically distributed mobile compute and data-intensive processing setting. ASO provides meaningful information to water resource managers in the Western US letting them know how much water to maintain; or release, and what the prospectus of the current snow season is in the Sierra Nevadas. Providing decision support products processed from airborne data in a 24 hour timeframe is an emergent field and required the team to develop a novel solution as this process is typically done over months. We've constructed a system that combines Apache OODT; with Apache Tika; with the Interactive Data Analysis (IDL)/ENVI programming environment to rapidly and unobtrusively generate, distribute and archive ASO data as soon as the plane lands near Mammoth Lakes, CA. Our system is flexible, underwent several redeployments and reconfigurations, and delivered this critical information to stakeholders during the recent "Snow On" campaign March 2013 - June 2013. This talk will take you through a day in the life of the compute team from data acquisition, delivery, processing, and dissemination. Within this context, we will discuss the architecture of ASO; the open source software we used; the data we stored; and how it was delivered to its users. Moreover we will discuss the logistics, system engineering, and staffing that went into the developing, deployment, and operation of the mobile compute system.

  15. Acute respiratory distress induced by repeated saline lavage provides stable experimental conditions for 24 hours in pigs.

    PubMed

    Muellenbach, Ralf M; Kredel, Markus; Zollhoefer, Bernd; Bernd, Zollhoefer; Johannes, Amelie; Kuestermann, Julian; Schuster, Frank; Schwemmer, Ulrich; Wurmb, Thomas; Wunder, Christian; Roewer, Norbert; Brederlau, Jörg

    2009-04-01

    Surfactant depletion is most often used to study acute respiratory failure in animal models. Because model stability is often criticized, the authors tested the following hypotheses: Repeated pulmonary lavage with normal saline provides stable experimental conditions for 24 hours with a PaO2/FiO2 ratio < 300 mm Hg. Lung injury was induced by bilateral pulmonary lavages in 8 female pigs (51.5 +/- 4.8 kg). The animals were ventilated for 24 hours (PEEP: 5 cm H2O; tidal volume: 6 mL/kg; respiratory rate: 30/min). After 24 hours the animals were euthanized. For histopathology slides from all pulmonary lobes were obtained. Supernatant of the bronchoalveolar fluid collected before induction of acute respiratory distress syndrome (ARDS) and after 24 hours was analyzed. A total of 19 +/- 6 lavages were needed to induce ARDS. PaO2/FiO2 ratio and pulmonary shunt fraction remained significantly deteriorated compared to baseline values after 24 hours (P < .01). Slight to moderate histopathologic changes were detected. Significant increases of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-6 were observed after 24 hours (P < .01). The presented surfactant depletion-based lung injury model was associated with increased pulmonary inflammation and fulfilled the criteria of acute ling injury (ALI) for 24 hours. PMID:19337905

  16. Association between Sleep Duration and 24-Hour Urine Free Cortisol in the MrOS Sleep Study

    PubMed Central

    Rao, Madhu N.; Blackwell, Terri; Redline, Susan; Punjabi, Naresh M.; Barrett-Connor, Elizabeth; Neylan, Thomas C.; Stone, Katie L.

    2013-01-01

    Context Short sleep duration is associated with adverse health outcomes, but the mechanisms involved are unknown. It has been postulated that short sleep duration may elevate cortisol levels, but studies have had conflicting results. It is unclear whether these differing findings may be due to methodological issues, such as assessment of sleep duration. Specifically, objective versus subjective methods of measuring habitual sleep duration may account for the conflicting results found in epidemiological studies. Objective Our goal was to determine whether habitual sleep duration, measured objectively (by actigraphy) and subjectively (by self-report), was associated with 24-hour urine free cortisol (UFC), a measure of integrated cortisol secretion. Our secondary goal was to determine whether slow wave sleep (SWS, determined by polysomnography) was associated with 24-hour UFC. Design/Setting Cross sectional study of community dwelling older men. Patients/Participants 325 men (mean age = 76.6 years, SD = 5.5) from the Portland site of the MrOS Sleep Study, who underwent 24-hour urine collection, polysomnography, actigraphy and sleep questionnaire. Primary Outcome 24-hour UFC. Results In this study of community dwelling older men, self-reported sleep duration was inversely related to 24-hour UFC levels. Participants reporting <5 hours of habitual sleep had an adjusted mean 24-hour UFC of 29.8 ug, compared to 28.0 ug in participants reporting >5 to <8 hours of sleep 25.5 ug in those reporting >8 hours of habitual sleep. However, sleep duration determined by actigraphy was not associated with 24-hour UFC in either univariable or multivariable regression models. SWS was not associated with 24-hour UFC. Conclusion Objectively measured (i.e., actigraphic) sleep duration is not associated with 24-hour UFC in these community dwelling older men. This finding, together with prior studies, suggests that elevated levels of integrated cortisol secretion is not the

  17. Pattern of 24 hour intragastric acidity in active duodenal ulcer disease and in healthy controls.

    PubMed Central

    Merki, H S; Fimmel, C J; Walt, R P; Harre, K; Röhmel, J; Witzel, L

    1988-01-01

    Twenty four hour intragastric acidity was measured by continuous recording using intragastric combined glass electrodes in 46 duodenal ulcer patients within 48 hours of endoscopic confirmation of active ulceration. Acidity during predefined time periods was compared with that measured in 40 healthy controls without gastrointestinal disease: it was significantly higher in duodenal ulcer patients at all times, but 25% of ulcer patients had median 24 hour acidity within the interquartile range of the normal group. During the evening (18,00 to 22,00 h) ulcer patients had considerable acidity with a median of 39.8 (63.1-31.6) mmol/l (interquartile range) compared with 5.6 (22.3-0.4) mmol/l of controls. It is suggested that antisecretory treatment be directed to decrease this period of unbuffered acidity, as well as during the night, which is presently considered of prime importance. PMID:3209116

  18. The Effects of 24-hour Sleep Deprivation on the Exploration-Exploitation Trade-off

    PubMed Central

    Glass, Brian D.; Maddox, W. Todd; Bowen, Christopher; Savarie, Zachary R.; Matthews, Michael D.; Markman, Arthur B.; Schnyer, David M.

    2010-01-01

    Sleep deprivation has a complex set of neurological effects that go beyond a mere slowing of mental processes. While cognitive and perceptual impairments in sleep deprived individuals are widespread, some abilities remain intact. In an effort to characterize these effects, some have suggested an impairment of complex decision making ability despite intact ability to follow simple rules. To examine this trade-off, 24-hour total sleep deprived individuals performed two versions of a resource acquisition foraging task, one in which exploration is optimal (to succeed, abandon low value, high saliency options) and another in which exploitation is optimal (to succeed, refrain from switching between options). Sleep deprived subjects exhibited decreased performance on the exploitation task compared to non-sleep deprived controls, yet both groups exhibited increased performance on the exploratory task. These results speak to previous neuropsychological work on cognitive control. PMID:21686036

  19. After 24-hour scrub, another tower rollback for the Boeing Delta II rocket carrying Stardust

    NASA Technical Reports Server (NTRS)

    1999-01-01

    As tower rollback begins, the Boeing Delta II rocket carrying the Stardust spacecraft waits on Launch Pad 17-A, Cape Canaveral Air Station, for the second launch attempt at 4:04 p.m. EST. The original launch was scrubbed on Feb. 6 for 24 hours. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  20. Tasimelteon: A Review in Non-24-Hour Sleep-Wake Disorder in Totally Blind Individuals.

    PubMed

    Keating, Gillian M

    2016-05-01

    Tasimelteon (Hetlioz(®)) is a dual melatonin receptor agonist indicated for the treatment of Non-24-Hour Sleep-Wake Disorder (Non-24) (free-running disorder). In two randomized, double-masked, multicentre, phase III trials, totally blind individuals with Non-24 who received oral tasimelteon 20 mg once nightly were significantly more likely than those receiving placebo to entrain the circadian pacemaker (the SET trial) and maintain entrainment (the RESET trial). Sleep/wake parameters and functioning were also improved with tasimelteon. Oral tasimelteon was generally well tolerated in totally blind patients with Non-24. In conclusion, tasimelteon is a useful drug for the treatment of Non-24 in totally blind individuals. PMID:27003694

  1. Setting Spacecraft Maximum Allowable Concentrations for 1 hour or 24 hour contingency exposures to airborne chemicals

    NASA Technical Reports Server (NTRS)

    Garcia, Hector D.; Limero, Thomas F.; James, John T.

    1992-01-01

    Since the early years of the manned space program, NASA has developed and used exposure limits called Spacecraft Maximum Allowable Concentrations (SMACs) to help protect astronauts from airborne toxicants. Most of these SMACS are based on an exposure duration of 7 days, since this is the duration of a 'typical' mission. A set of 'contingency SMACs' is also being developed for scenarios involving brief (1-hour or 24- hour) exposures to relatively high levels of airborne toxicants from event-related 'contingency' releases of contaminants. The emergency nature of contingency exposures dictates the use of different criteria for setting exposure limits. The NASA JSC Toxicology Group recently began a program to document the rationales used to set new SMACs and plans to review the older, 7-day SMACs. In cooperation with the National Research Council's Committee on Toxicology, a standard procedure has been developed for researching, setting, and documenting SMAC values.

  2. Novel description of the 24-hour circadian rhythms of brachial versus central aortic blood pressure and the impact of blood pressure treatment in a randomized controlled clinical trial: The Ambulatory Central Aortic Pressure (AmCAP) Study.

    PubMed

    Williams, Bryan; Lacy, Peter S; Baschiera, Fabio; Brunel, Patrick; Düsing, Rainer

    2013-06-01

    Elevated brachial blood pressure (BP) is associated with increased cardiovascular risk and predicts morbidity and mortality in humans. Recently, 24-hour ambulatory BP monitoring and assessment of central aortic BP have been introduced to improve BP phenotyping. The Ambulatory Central Aortic Pressure (AmCAP) study combines these approaches and describes, for the first time, the diurnal patterns of simultaneously measured 24-hour ambulatory brachial and central pressures in a prespecified substudy embedded within a clinical trial of BP lowering in patients with hypertension. Twenty-four-hour ambulatory brachial and central pressure measurements were acquired using a tonometer mounted into the articulating strap of a wristwatch-like device (BPro) in 171 participants with hypertension recruited into the ASSERTIVE (AliSkiren Study of profound antihypERtensive efficacy in hyperTensIVE patients) trial. Participants were randomly assigned to BP lowering with either aliskiren 300 mg QD or telmisartan 80 mg QD for 12 weeks. Ambulatory brachial and central BP was measured in all participants both at baseline and at study end. Brachial and central BP both demonstrated typical diurnal patterns with lower pressures at night. However, night time was associated with smaller reductions in central relative to brachial pressure and decreased pulse pressure amplification (P<0.0001 for both). These effects were not modulated after BP lowering and were maintained after adjustment for day and night-time BP and heart rate (P=0.02). This study demonstrates that brachial and central pressure show different diurnal patterns, which are not modulated by BP-lowering therapy, with relatively higher night-time central pressures. These novel data indicate that night-time central BP may provide prognostic importance and warrants further investigation. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00865020. PMID:23630950

  3. The association of knowledge, attitudes and behaviours related to salt with 24-hour urinary sodium excretion

    PubMed Central

    2014-01-01

    Aim Salt reduction efforts usually have a strong focus on consumer education. Understanding the association between salt consumption levels and knowledge, attitudes and behaviours towards salt should provide insight into the likely effectiveness of education-based programs. Methods A single 24-hour urine sample and a questionnaire describing knowledge, attitudes and behaviours was obtained from 306 randomly selected participants and 113 volunteers from a regional town in Australia. Results Mean age of all participants was 55 years (range 20–88), 55% were women and mean 24-hour urinary salt excretion was 8.8(3.6) g/d. There was no difference in salt excretion between the randomly selected and volunteer sample. Virtually all participants (95%) identified that a diet high in salt can cause serious health problems with the majority of participants (81%) linking a high salt diet to raised blood pressure. There was no difference in salt excretion between those who did 8.7(2.1) g/d and did not 7.5(3.3) g/d identify that a diet high in salt causes high blood pressure (p = 0.1). Nor was there a difference between individuals who believed they consumed “too much” 8.9(3.3) g/d “just the right amount” 8.4(2.6) g/d or “too little salt” 9.1(3.7) g/d (p = 0.2). Likewise, individuals who indicated that lowering their salt intake was important 8.5(2.9) g/d vs. not important 8.8(2.4) g/d did not have different consumption levels (p = 0.4). Conclusion The absence of a clear association between knowledge, attitudes and behaviours towards salt and actual salt consumption suggests that interventions focused on knowledge, attitudes and behaviours alone may be of limited efficacy. PMID:24708561

  4. Fasting for 24 Hours Heightens Reward from Food and Food-Related Cues

    PubMed Central

    Cameron, Jameason D.; Goldfield, Gary S.; Finlayson, Graham; Blundell, John E.; Doucet, Éric

    2014-01-01

    Introduction We examined the impact of a 24 hour complete fast (vs. fed state) on two measures of food reward: 1) ‘wanting’, as measured by response to food images and by the relative-reinforcing value of food (RRV), and 2) ‘liking’, as measured by response to food images and the hedonic evaluation of foods consumed. Methods Utilizing a randomized crossover design, 15 subjects (9 male; 6 female) aged 28.6±4.5 yrs with body mass index 25.3±1.4 kg/m2 were randomized and counterbalanced to normal feeding (FED) and 24-hour fast (FASTED) conditions. Trait characteristics were measured with the Three Factor Eating Questionnaire. Two computer tasks measured food reward: 1) RRV progressive ratio task, 2) explicit ‘liking’ and ‘wanting’ (Leeds Food Preference Questionnaire, LFPQ). Also measured were ad libitum energy intake (EI; buffet) and food ‘liking’ (visual analogue scale) of personalized stimuli. Results There were no significant anthropometric changes between conditions. Appetite scores, hedonic ratings of ‘liking’, and ad libitum EI all significantly increased under the FASTED condition (p<0.05). Under the FASTED condition there were significant increases in the RRV of snack foods; similarly, explicit ‘wanting’ and ‘liking’ significantly increased for all food categories. ‘Liking’ of sweet foods remained high across-meals under FASTED, but savory foods decreased in hedonic saliency. Conclusion Relative to a fed state, we observed an increase in hedonic ratings of food, the rewarding value of food, and food intake after a 24 hr fast. Alliesthesia to food and food cues is suggested by heightened hedonic ratings under the FASTED condition relative to FED. PMID:24454949

  5. A 24-Hour Study of the Hypothalamo-Pituitary Axes in Huntington’s Disease

    PubMed Central

    Nambron, Rajasree; Costelloe, Seán J.; Martin, Nicholas G.; Hill, Nathan R.; Frost, Chris; Watt, Hilary C.; Hindmarsh, Peter; Björkqvist, Maria; Warner, Thomas T.

    2015-01-01

    Background Huntington’s disease is an inherited neurodegenerative disorder characterised by motor, cognitive and psychiatric disturbances. Patients exhibit other symptoms including sleep and mood disturbances, muscle atrophy and weight loss which may be linked to hypothalamic pathology and dysfunction of hypothalamo-pituitary axes. Methods We studied neuroendocrine profiles of corticotropic, somatotropic and gonadotropic hypothalamo-pituitary axes hormones over a 24-hour period in controlled environment in 15 healthy controls, 14 premanifest and 13 stage II/III Huntington’s disease subjects. We also quantified fasting levels of vasopressin, oestradiol, testosterone, dehydroepiandrosterone sulphate, thyroid stimulating hormone, free triiodothyronine, free total thyroxine, prolactin, adrenaline and noradrenaline. Somatotropic axis hormones, growth hormone releasing hormone, insulin-like growth factor-1 and insulin-like factor binding protein-3 were quantified at 06:00 (fasting), 15:00 and 23:00. A battery of clinical tests, including neurological rating and function scales were performed. Results 24-hour concentrations of adrenocorticotropic hormone, cortisol, luteinizing hormone and follicle-stimulating hormone did not differ significantly between the Huntington’s disease group and controls. Daytime growth hormone secretion was similar in control and Huntington’s disease subjects. Stage II/III Huntington’s disease subjects had lower concentration of post-sleep growth hormone pulse and higher insulin-like growth factor-1:growth hormone ratio which did not reach significance. In Huntington’s disease subjects, baseline levels of hypothalamo-pituitary axis hormones measured did not significantly differ from those of healthy controls. Conclusions The relatively small subject group means that the study may not detect subtle perturbations in hormone concentrations. A targeted study of the somatotropic axis in larger cohorts may be warranted. However, the lack

  6. The effect of Operation 24 Hours on reducing collision in the City of Edmonton.

    PubMed

    Halim, Siana; Jiang, Heming

    2013-09-01

    In the City of Edmonton, in order to reduce the prevalence of collisions, the Operation 24 Hours program (OPS24) was developed by using existing police and transportation services resources. The program uses traditional manned police speed enforcement method, which are supplemented by traffic safety messages displayed on permanent and mobile dynamic messaging signs (DMS). In this paper, collision data analysis was performed by looking at the daily number of collisions from 2008 to 2011 that covers 28 Operation 24 Hours (OPS24) events. The objective of the collision data analysis is to analyze if there is a reduction in collision frequencies after OPS24 was held and examined how long the collision reduction effect last. Weather factors such as temperature, thickness of snow, and wind gust have been considered by many as a great influence on collision occurrences, especially in a city with long and cold winter such as Edmonton. Therefore, collision modeling was performed by considering these external weather factors. To analyze the linear and periodic trend of different collision types (injury, fatal, and property damage only (PDO)) and examine the influence of weather factors on collisions, negative binomial time series model that accounts for seasonality and weather factors was used to model daily collision data. The modeling also considered collision proportion to account for missing traffic volume data; the Gaussian time series model that accounts for seasonality and weather factors was used to model collision proportion. To estimate the collision trend and test for changes in collision levels before/after OPS24, interrupted time series model with segmented regression was used. While for estimating how long the effect of the OPS24 last, change point method was applied. PMID:23727551

  7. Heart rate variability and arrhythmic patterns of 24-hour Holter electrocardiography among Nigerians with cardiovascular diseases

    PubMed Central

    Adebayo, Rasaaq Ayodele; Ikwu, Amanze Nkemjika; Balogun, Michael Olabode; Akintomide, Anthony Olubunmi; Ajayi, Olufemi Eyitayo; Adeyeye, Victor Oladeji; Mene-Afejuku, Tuoyo Omasan; Bamikole, Olaniyi James; Ogunyemi, Suraj Adefabi; Ajibare, Adeola Olubunmi; Oketona, Omolola Abiodun

    2015-01-01

    Background Facilities for Holter electrocardiography (ECG) monitoring in many Nigerian hospitals are limited. There are few published works in Nigeria on the use of 24-hour Holter ECG in cardiac arrhythmic evaluation of patients with cardiovascular diseases. Objective To study the clinical indications, arrhythmic pattern, and heart rate variability (HRV) among subjects referred for 24-hour Holter ECG at our Cardiac Care Unit. Methods Three-hundred and ten patients (134 males and 176 females) were studied consecutively over a 48-month period using Schiller type (MT-101) Holter ECG machine. Results Out of the 310 patients reviewed, 134 were males (43.2%) and 176 were females (56.8%). The commonest indication for Holter ECG was palpitation followed by syncope in 71 (23%) and 49 (15.8%) of subjects, respectively. Premature ventricular complex and premature atrial complex were the commonest types of arrhythmia in 51.5% and 15% subjects, respectively. Ventricular arrhythmia was more prevalent in dilated cardiomyopathy patients (85.7%). The HRV of subjects with palpitation, stroke, and diabetes mellitus with autonomic neuropathy, using standard deviation of normal to normal intervals average (milliseconds), were 107.32±49.61, 79.15±49.15, and 66.50±15.54, respectively. The HRV, using standard deviation of averages of normal to normal intervals average (milliseconds), of patients with palpitation, stroke, and diabetes mellitus with autonomic neuropathy were 77.39±62.34, 57.82±37.05, and 55.50±12.71, respectively. Conclusion Palpitation and syncope were the commonest indications for Holter ECG among our subjects. The commonest arrhythmic patterns were premature ventricular complex and premature atrial complex, with ventricular arrhythmia being more prevalent in dilated cardiomyopathy. There was a reduction in HRV in patients with stroke and diabetic autonomic neuropathy. PMID:26170685

  8. Effects of exenatide and liraglutide on 24-hour glucose fluctuations in type 2 diabetes.

    PubMed

    Nagakura, Jo; Yamakawa, Tadashi; Taguri, Masataka; Tsuchiya, Hirohisa; Shigematsu, Erina; Suzuki, Jun; Morita, Satoshi; Kadonosono, Kazuaki; Terauchi, Yasuo

    2016-03-31

    We evaluated the influence of short-term treatment with exenatide twice daily or liraglutide once daily on daily blood glucose fluctuations in 40 patients with type 2 diabetes inadequately controlled by sulfonylureas. The patients in a multicenter, open-label trial were randomly assigned to receive add-on exenatide (10 μg/day, n = 21) or add-on liraglutide (0.3-0.9 mg/day, n = 19), and underwent 24-hour continuous subcutaneous glucose monitoring. There was no significant between-group difference in glucose fluctuations during the day, as assessed by calculating mean amplitude of glycemic excursion (MAGE) and standard deviation (SD). However, the mean blood glucose levels at 3 hours after breakfast and dinner were significantly lower in the exenatide group than the liraglutide group (breakfast: 127.3 ± 24.1 vs. 153.4 ± 28.7 mg/dL; p = 0.006, dinner: 108.7 ± 17.3 vs. 141.9 ± 24.2 mg/dL; p < 0.001). In contrast, mean blood glucose levels and their SD were significantly lower between 0000 h and 0600 h in the liraglutide group than the exenatide group (average glucose: 126.9 ± 27.1 vs. 107.1 ± 24.0 mg/dL; p = 0.029, SD: 15.2 ± 10.5 vs. 8.7 ± 3.8; p = 0.020). Both groups had similar glucose fluctuations despite differences in 24-hour blood glucose profiles. Therefore, each of these agents may have advantages or disadvantages and should be selected according to the blood glucose profile of the patient. PMID:26743240

  9. Time-Based Measurement of Personal Mite Allergen Bioaerosol Exposure over 24 Hour Periods.

    PubMed

    Tovey, Euan R; Liu-Brennan, Damien; Garden, Frances L; Oliver, Brian G; Perzanowski, Matthew S; Marks, Guy B

    2016-01-01

    Allergic diseases such as asthma and rhinitis are common in many countries. Globally the most common allergen associated with symptoms is produced by house dust mites. Although the bed has often been cited as the main site of exposure to mite allergens, surprisingly this has not yet been directly established by measurement due to a lack of suitable methods. Here we report on the development of novel methods to determine the pattern of personal exposure to mite allergen bioaerosols over 24-hour periods and applied this in a small field study using 10 normal adults. Air was sampled using a miniature time-based air-sampler of in-house design located close to the breathing zone of the participants, co-located with a miniature time-lapse camera. Airborne particles, drawn into the sampler at 2L/min via a narrow slot, were impacted onto the peripheral surface of a disk mounted on the hour-hand of either a 12 or 24 hour clock motor. The impaction surface was either an electret cloth, or an adhesive film; both novel for these purposes. Following a review of the time-lapse images, disks were post-hoc cut into subsamples corresponding to eight predetermined categories of indoor or outdoor location, extracted and analysed for mite allergen Der p 1 by an amplified ELISA. Allergen was detected in 57.2% of the total of 353 subsamples collected during 20 days of sampling. Exposure patterns varied over time. Higher concentrations of airborne mite allergen were typically measured in samples collected from domestic locations in the day and evening. Indoor domestic Der p 1 exposures accounted for 59.5% of total exposure, whereas total in-bed-asleep exposure, which varied 80 fold between individuals, accounted overall for 9.85% of total exposure, suggesting beds are not often the main site of exposure. This study establishes the feasibility of novel methods for determining the time-geography of personal exposure to many bioaerosols and identifies new areas for future technical

  10. Time-Based Measurement of Personal Mite Allergen Bioaerosol Exposure over 24 Hour Periods

    PubMed Central

    Tovey, Euan R.; Liu-Brennan, Damien; Garden, Frances L.; Oliver, Brian G.; Perzanowski, Matthew S.; Marks, Guy B.

    2016-01-01

    Allergic diseases such as asthma and rhinitis are common in many countries. Globally the most common allergen associated with symptoms is produced by house dust mites. Although the bed has often been cited as the main site of exposure to mite allergens, surprisingly this has not yet been directly established by measurement due to a lack of suitable methods. Here we report on the development of novel methods to determine the pattern of personal exposure to mite allergen bioaerosols over 24-hour periods and applied this in a small field study using 10 normal adults. Air was sampled using a miniature time-based air-sampler of in-house design located close to the breathing zone of the participants, co-located with a miniature time-lapse camera. Airborne particles, drawn into the sampler at 2L/min via a narrow slot, were impacted onto the peripheral surface of a disk mounted on the hour-hand of either a 12 or 24 hour clock motor. The impaction surface was either an electret cloth, or an adhesive film; both novel for these purposes. Following a review of the time-lapse images, disks were post-hoc cut into subsamples corresponding to eight predetermined categories of indoor or outdoor location, extracted and analysed for mite allergen Der p 1 by an amplified ELISA. Allergen was detected in 57.2% of the total of 353 subsamples collected during 20 days of sampling. Exposure patterns varied over time. Higher concentrations of airborne mite allergen were typically measured in samples collected from domestic locations in the day and evening. Indoor domestic Der p 1 exposures accounted for 59.5% of total exposure, whereas total in-bed-asleep exposure, which varied 80 fold between individuals, accounted overall for 9.85% of total exposure, suggesting beds are not often the main site of exposure. This study establishes the feasibility of novel methods for determining the time-geography of personal exposure to many bioaerosols and identifies new areas for future technical

  11. Non-24-Hour Sleep-Wake Disorder Revisited – A Case Study

    PubMed Central

    Garbazza, Corrado; Bromundt, Vivien; Eckert, Anne; Brunner, Daniel P.; Meier, Fides; Hackethal, Sandra; Cajochen, Christian

    2016-01-01

    The human sleep-wake cycle is governed by two major factors: a homeostatic hourglass process (process S), which rises linearly during the day, and a circadian process C, which determines the timing of sleep in a ~24-h rhythm in accordance to the external light–dark (LD) cycle. While both individual processes are fairly well characterized, the exact nature of their interaction remains unclear. The circadian rhythm is generated by the suprachiasmatic nucleus (“master clock”) of the anterior hypothalamus, through cell-autonomous feedback loops of DNA transcription and translation. While the phase length (tau) of the cycle is relatively stable and genetically determined, the phase of the clock is reset by external stimuli (“zeitgebers”), the most important being the LD cycle. Misalignments of the internal rhythm with the LD cycle can lead to various somatic complaints and to the development of circadian rhythm sleep disorders (CRSD). Non-24-hour sleep-wake disorders (N24HSWD) is a CRSD affecting up to 50% of totally blind patients and characterized by the inability to maintain a stable entrainment of the typically long circadian rhythm (tau > 24.5 h) to the LD cycle. The disease is rare in sighted individuals and the pathophysiology less well understood. Here, we present the case of a 40-year-old sighted male, who developed a misalignment of the internal clock with the external LD cycle following the treatment for Hodgkin’s lymphoma (ABVD regimen, four cycles and AVD regimen, four cycles). A thorough clinical assessment, including actigraphy, melatonin profiles and polysomnography led to the diagnosis of non-24-hour sleep-wake disorders (N24HSWD) with a free-running rhythm of tau = 25.27 h. A therapeutic intervention with bright light therapy (30 min, 10,000 lux) in the morning and melatonin administration (0.5–0.75 mg) in the evening failed to entrain the free-running rhythm, although a longer treatment duration and more intense therapy

  12. Non-24-Hour Sleep-Wake Disorder Revisited - A Case Study.

    PubMed

    Garbazza, Corrado; Bromundt, Vivien; Eckert, Anne; Brunner, Daniel P; Meier, Fides; Hackethal, Sandra; Cajochen, Christian

    2016-01-01

    The human sleep-wake cycle is governed by two major factors: a homeostatic hourglass process (process S), which rises linearly during the day, and a circadian process C, which determines the timing of sleep in a ~24-h rhythm in accordance to the external light-dark (LD) cycle. While both individual processes are fairly well characterized, the exact nature of their interaction remains unclear. The circadian rhythm is generated by the suprachiasmatic nucleus ("master clock") of the anterior hypothalamus, through cell-autonomous feedback loops of DNA transcription and translation. While the phase length (tau) of the cycle is relatively stable and genetically determined, the phase of the clock is reset by external stimuli ("zeitgebers"), the most important being the LD cycle. Misalignments of the internal rhythm with the LD cycle can lead to various somatic complaints and to the development of circadian rhythm sleep disorders (CRSD). Non-24-hour sleep-wake disorders (N24HSWD) is a CRSD affecting up to 50% of totally blind patients and characterized by the inability to maintain a stable entrainment of the typically long circadian rhythm (tau > 24.5 h) to the LD cycle. The disease is rare in sighted individuals and the pathophysiology less well understood. Here, we present the case of a 40-year-old sighted male, who developed a misalignment of the internal clock with the external LD cycle following the treatment for Hodgkin's lymphoma (ABVD regimen, four cycles and AVD regimen, four cycles). A thorough clinical assessment, including actigraphy, melatonin profiles and polysomnography led to the diagnosis of non-24-hour sleep-wake disorders (N24HSWD) with a free-running rhythm of tau = 25.27 h. A therapeutic intervention with bright light therapy (30 min, 10,000 lux) in the morning and melatonin administration (0.5-0.75 mg) in the evening failed to entrain the free-running rhythm, although a longer treatment duration and more intense therapy might have

  13. Personal best marathon time and longest training run, not anthropometry, predict performance in recreational 24-hour ultrarunners.

    PubMed

    Knechtle, Beat; Knechtle, Patrizia; Rosemann, Thomas; Lepers, Romuald

    2011-08-01

    In recent studies, a relationship between both low body fat and low thicknesses of selected skinfolds has been demonstrated for running performance of distances from 100 m to the marathon but not in ultramarathon. We investigated the association of anthropometric and training characteristics with race performance in 63 male recreational ultrarunners in a 24-hour run using bi and multivariate analysis. The athletes achieved an average distance of 146.1 (43.1) km. In the bivariate analysis, body mass (r = -0.25), the sum of 9 skinfolds (r = -0.32), the sum of upper body skinfolds (r = -0.34), body fat percentage (r = -0.32), weekly kilometers ran (r = 0.31), longest training session before the 24-hour run (r = 0.56), and personal best marathon time (r = -0.58) were related to race performance. Stepwise multiple regression showed that both the longest training session before the 24-hour run (p = 0.0013) and the personal best marathon time (p = 0.0015) had the best correlation with race performance. Performance in these 24-hour runners may be predicted (r2 = 0.46) by the following equation: Performance in a 24-hour run, km) = 234.7 + 0.481 (longest training session before the 24-hour run, km) - 0.594 (personal best marathon time, minutes). For practical applications, training variables such as volume and intensity were associated with performance but not anthropometric variables. To achieve maximum kilometers in a 24-hour run, recreational ultrarunners should have a personal best marathon time of ∼3 hours 20 minutes and complete a long training run of ∼60 km before the race, whereas anthropometric characteristics such as low body fat or low skinfold thicknesses showed no association with performance. PMID:21642857

  14. Continuous 24 hour ambulatory monitoring of intragastric pH in man.

    PubMed

    Kapur, B K; Howlett, P J; Kenyon, N G; Lunt, M J; Mills, J G; Smallwood, R H; Wilson, A J; Bardhan, K D

    1987-05-01

    A system has been developed which permits continuous 24 hour ambulatory recording of intragastric pH under near-physiological conditions. The system utilises a Cecar combination pH electrode connected through a pre-amplifier to an Oxford Medical Systems Medilog 4-24 cassette recorder, and the pH recorded continuously on to tape. The data is replayed at high speed, digitised and then analysed. Sources of error included system drift, system noise and the effect of changes in electrode environment due to saliva, food, loss of fluid contact, temperature variations and electrode time constant. These were found to be small. In contrast, the major changes in pH detected reflect real changes at the electrode tip. These changes can be recorded by the system. Developments in electronics and improvements in both the size and quality of pH electrodes, over the past few decades, has enabled intragastric pH recordings to be made with greater ease. However, a large number of investigators still assess gastric acidity by infrequent, intermittent sampling of gastric secretion through a naso-gastric tube. This new ambulatory system is a significant improvement and its versatility allows studies in acid secretion physiology, pharmacology and pathophysiology. PMID:3595080

  15. The Canadian 24-Hour Movement Guidelines for Children and Youth: Implications for practitioners, professionals, and organizations.

    PubMed

    Latimer-Cheung, Amy E; Copeland, Jennifer L; Fowles, Jonathon; Zehr, Lori; Duggan, Mary; Tremblay, Mark S

    2016-06-01

    The new Canadian 24-Hour Movement Guidelines for Children and Youth emphasize the integration of all movement behaviours that occur over a whole day (i.e., light, moderate, and vigorous physical activity, sedentary behaviour, and sleep). These guidelines shift the paradigm away from considering each behaviour in isolation. This concept of the "whole day matters" not only calls for a change in thinking about movement but also for redevelopment of dissemination and implementation practice. Past guideline launch activities largely have aimed to create awareness through passive dissemination strategies (e.g., Website posts, distribution of print resources). For the integrated guidelines to have public health impact, we must move beyond dissemination and raising of awareness to implementation and behaviour change. Shifting this focus requires new, innovative approaches to intervention, including interdisciplinary collaboration, policy change, and refocused service provision. The purpose of this paper is to identify practitioners, professionals, and organizations with potential to disseminate and/or implement the guidelines, discuss possible implementation strategies for each of these groups, and describe the few resources being developed and those needed to support dissemination and implementation efforts. This discussion makes readily apparent the need for a well-funded, comprehensive, long-term dissemination, implementation, and evaluation plan to ensure uptake and activation of the guidelines. PMID:27306438

  16. [The diagnostic impact and limitations of 24 hour pH monitoring with multichannel intraluminal impedance].

    PubMed

    Korszun, Karolina; Dyrla, Przemysław; Wojtuń, Stanisław; Gil, Jerzy

    2014-08-01

    Gastroesophageal reflux disease (GERD) is a result of reflux of gastric contents into the esophagus. Gastroscopy is often the first examination performed in GERD diagnosis. Some patients have macroscopic lesions, namely erosions, in the esophagus above the cardia of stomach. It enables to diagnose gastroesophageal reflux disease. However, many patients have no macroscopic lesions of the esophageal mucosa in endoscopy. That is why 24-hour pH monitoring with multichannel intraluminal impedance is the gold standard in diagnosis establishing of GERD and make feasible to distinguish acid, weakly acid and nonacid reflux and its correlation with reported symptoms. Impedance-pH is used to establish diagnosis of GERD, in patient qualification to anti-reflux surgery, to find the cause of not efficient reflux disease treatment as well as the cause of extra-esophageal symptoms of reflux disease. During impedance-pH test catheter connected with the recorder is placed in patient's esophagus. Recorded data is analyzed with the computer program. The examination is safe, the only complication that can occur is nasal bleeding, which can be a result of mucosa damage caused while catheter implementation. Nowadays disposable catheters are used, that excludes the risk of catheter related infection. On the basis of pH-impedance results it is possible to divide patients into 3 groups: patients with functional heartburn, patients with esophageal hypersensitivity and abnormal esophageal acid exposure. This classification is very helpful in the choice of treatment - antireflux surgery, proton pump inhibitor or prokinetic therapy. PMID:25252438

  17. Evaluation study of the California Expanded Food and Nutrition Education Program: 24-hour food recall data.

    PubMed

    Del Tredici, A M; Joy, A B; Omelich, C L; Laughlin, S G

    1988-02-01

    The California Expanded Food and Nutrition Education program (EFNEP) Evaluation Study evaluated the effectiveness of the California program. The eating habits of 683 persons were studied in a group receiving EFNEP instruction (355 participants) and a control group (328 participants) that received no instruction. The 24-hour food recall was used to assess eating habits using the Synectics method. At the beginning of the study, there were no differences in food recall scores between the EFNEP and the control groups. After 6 months of instruction in the EFNEP group, there was a significant increase in food recall score for that group and no change in the control group. The improvements observed in the EFNEP group resulted from increased intakes from the milk, protein, and fruit and vegetable food groups. The program characteristics that led to those changes were determined to be in the length of the EFNEP visit, the number of EFNEP visits, and the EFNEP instruction topics. These results show that the California EFNEP is effective in producing significant changes in the eating habits of the low-income individuals it serves. PMID:3339205

  18. Electrodes for 24 hours pH monitoring--a comparative study.

    PubMed

    McLauchlan, G; Rawlings, J M; Lucas, M L; McCloy, R F; Crean, G P; McColl, K E

    1987-08-01

    Three pH electrodes in clinical use were examined--(1) antimony electrode with remote reference electrode (Synectics 0011), (2) glass electrode with remote reference electrode (Microelectrodes Inc. MI 506) and (3) combined glass electrode with integral reference electrode (Radiometer GK2801C). In vitro studies showed that both glass electrodes were similar and superior to the antimony electrode with respect to response time, drift, and sensitivity. The effect of the siting of the reference electrode on the recorded pH was examined in five human volunteers. The pH reading using a remote skin reference electrode was higher by a mean of 0.3 pH units (range 0.0-0.6) in the stomach, lower by 0.65 pH units (0.5-0.8) in the duodenum and lower by 0.3 pH units (0.0-0.6) in the oesophagus than that simultaneously obtained with an intraluminal reference electrode. Buccal reference electrodes gave similar readings to skin. Combined reference and glass pH electrodes are recommended for 24-hour ambulatory pH monitoring. PMID:3666560

  19. After 24-hour scrub, the Boeing Delta II rocket carrying Stardust launches on time

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Flames sear the pristine blue sky behind the Boeing Delta II rocket carrying the Stardust spacecraft after the 4:04:15 p.m. launch from Launch Pad 17-A, Cape Canaveral Air Station. A 24- hour scrub postponed the launch from the originally scheduled date of Feb. 6. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  20. After 24-hour scrub, the Boeing Delta II rocket carrying Stardust waits for launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    In the late morning light at Launch Pad 17-A, Cape Cananveral Air Station, the fixed utility tower (right) casts a long shadow across the base of the Boeing Delta II rocket (left) waiting to launch the Stardust spacecraft. After a 24-hour scrub, the new targeted launch time is 4:04 p.m. EST. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  1. After 24-hour scrub, the Boeing Delta II rocket carrying Stardust waits for launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    After a 24-hour postponement, the Boeing Delta II rocket carrying the Stardust spacecraft waits on Launch Pad 17-A, Cape Canaveral Air Station, for its scheduled launch at 4:04 p.m. EST. Umbilical lines (at top) still attached to the fixed utility tower (at right) feed electricity, air conditioning and coolants for the Stardust spacecraft inside the fairing (enclosing the upper stage) before launch. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  2. Age and individual sleep characteristics affect cognitive performance in anesthesiology residents after a 24-hour shift.

    PubMed

    Tadinac, Meri; Sekulić, Ante; Hromatko, Ivana; Mazul-Sunko, Branka; Ivancić, Romina

    2014-03-01

    Previous research has shown that both shift work and sleep deprivation have an adverse influence on various aspects of human cognitive performance. The aim of this study was to explore changes in cognitive functioning and subjective sleepiness of anesthesiology residents after a 24-hour shift. Twenty-six anesthesiology residents completed a set of psychological instruments at the beginning and at the end of the shift, as well as a questionnaire regarding information about the shift, Stanford Sleepiness Scale, and Circadian Type Questionnaire. There was a significant decline in cognitive performance measured by the Auditory Verbal Learning Test after the shift. The effect was stronger in older participants and in those with high scores on rigidity of sleep scale and low scores on the ability to overcome sleepiness scale. There were no differences in the digits forward test (a measure of concentration), while digits backward test (a measure of working memory) even showed an improved performance after the shift. Although participants reported being significantly sleepier after the shift, the subjective sleepiness did not correlate with any of the objective measures of cognitive performance. In conclusion, the performance in short tasks involving concentration and working memory was not impaired, while performance in long-term and monotone tasks declined after sleep deprivation, and the magnitude of this decline depended on the specific individual characteristics of sleep and on age Surprisingly, age seemed to have an important impact on cognitive functions after shift work even in the relatively age-homogeneous population of young anesthesiology residents. PMID:24974663

  3. Importance of all movement behaviors in a 24 hour period for overall health.

    PubMed

    Chaput, Jean-Philippe; Carson, Valerie; Gray, Casey E; Tremblay, Mark S

    2014-12-01

    Physical inactivity and childhood obesity are well-recognized public health concerns that are associated with a range of adverse health outcomes. Historically, the benefits of physical activity (e.g., moderate-to-vigorous physical activity-MVPA) to overall health have dominated discussions and emerging evidence indicates that a broader, more integrated approach is needed to better understand and address current public health crises. Existing guidelines for children and youth around the world only focus on MVPA, and recently sedentary behavior, despite an accumulating body of evidence showing that light-intensity physical activity (LPA) such as walking can provide important health benefits. Furthermore, there is accumulating support for the importance of adequate sleep and that these behaviors moderate the health impact of each other. Ignoring the other components of the movement continuum (i.e., sleep, sedentary time, LPA) while focusing efforts exclusively on MVPA (accounting for <5% of the time in a 24 h period) limits the potential to optimize the health benefits of movement behaviors. In order to address this limitation, experts in Canada are currently developing the world's first Integrated 24 Hour Movement Behaviour Guidelines for Children and Youth to help advance an integrated healthy active living agenda that has the potential to significantly improve the overall health and well-being of children and youth. PMID:25485978

  4. Accuracy of commercial 24-hour electrocardiogram analyzers for quantitation of total and repetitive ventricular arrhythmias.

    PubMed

    Salerno, D M; Granrud, G; Hodges, M

    1987-12-01

    The accuracy of 2 commercial 24-hour electrocardiogram analyzers was tested for quantitation of ventricular premature complexes (VPCs). Scanner 1 was the Cardiodata Systems Mark III and scanner 2 was the Avionics Trendsetter DCG VII. Twenty-four-hour electrocardiographic recordings from 19 consecutive ambulatory patients with frequent VPCs were analyzed by each device. Results were compared with those from hand counts of complete printouts of each of the 19 recordings. For total VPCs, scanner 1 had an average error of 13% (range 0 to 58%) and scanner 2 had an average error of 24% (range (1 to 80%). Scanner 1 had an error of more than 10% for 9 of the 19 recordings and scanner 2 more than 10% for 11 of the 19 recordings. For paired VPCs, scanner 1 had a mean error of 23% (range 4 to 77%), and scanner 2 of 56% (range 34 to 79%). For nonsustained ventricular tachycardia, scanner 1 had an average error of 20% (range 8 to 41%) and scanner 2 had an error of 56% (range 34 to 78%). Thus, when recordings from consecutive ambulatory patients with frequent VPCs were analyzed, neither device was consistently accurate for quantitation of total VPCs. Both analyzers had an unacceptable error for quantitation of repetitive VPCs. All currently available devices may have comparably large errors. This possibility is confirmed by recalculation of the reported data from a third scanner. PMID:2446488

  5. Obtaining liver tridimensional scaffold through the decellularization of rabbit whole liver in 24 hours

    NASA Astrophysics Data System (ADS)

    Federico, Schliamser; Ayelen, Rinaldi; Romina, Comin; Alba Nelly, Borchert; Adrian, Nari Gustavo; Alicia, Salvatierra Nancy; Mariana Paula, Cid

    2016-04-01

    In the present work, we development a new protocol for liver decellularization in which the hole decellularization was reached over 24 h. Introduction: the availability of transplantable livers is not sufficient to fulfill the current demand for grafts, with the search for therapeutic alternatives having generated different lines of research, one of which is the use of decellularized three-dimensional biological matrices and subsequent cell seeding to obtain a functional organ. Objective: to produce a decellularization protocol from rabbit liver to generate a three-dimensional matrixin which the time period involved didn't pass 24 h. Methods: The decellularization is obtained through the use of water and SDS (0,1-0,3 %), after freezing at -80 degrees, is the best alternative of different physical and/or chemical mechanisms to break down organ cells and leave only the extracellular matriz. After 24 h of retrograde perfusion, a decellularized translucent matrix was generated. To evaluate if the decellularization protocol was successful, with the extracellular matrix being preserved, we carried out histological (light microscopy) and biochemical (DNA quantification) studies. Results: the decellularization process was verified by macroscopic observation of the organ using microscopic observation corroborated the macroscopic results, with the hematoxylin-eosin and Masson staining showing no cells or nuclear material. In addition, the DNA quantification was less than 10% in the decellularized liver compared to control. Finally,the time taken to develop the decellularization protocol was less than 24 hours.

  6. Association between Diurnal Variation of Ozone Concentration and Stroke Occurrence: 24-Hour Time Series Study

    PubMed Central

    Han, Myung-Hoon; Yi, Hyeong-Joong; Kim, Young-Seo; Ko, Yong; Kim, Young-Soo

    2016-01-01

    Background and Purpose Increasing ozone concentrations have been known to damage human health and ecosystems. Although ozone tends to display diurnal variation, most studies have reported only on the association between daily ozone concentrations and ischemic stroke occurrence on the same day, or with a 1-day lag. We investigated the effect of the diurnal variation of ozone on ischemic stroke occurrence during the same day. Methods We included a consecutive series of 1,734 patients from January 1, 2008, to December 31, 2014, at a single tertiary hospital in Seoul, South Korea. We evaluated differences between temperature and pollutants at the time of stroke onset for each time interval and averaged those parameters across the 7-year study period. Results During the interval from 13:00 to 16:59, we found a positive association between ischemic stroke occurrence and ozone concentration relative to other time periods. Upper median ozone levels from 13:00 to 16:59 were positively correlated with ischemic stroke (odds ratio, 1.550; 95% confidence intervals, 1.220 to 1.970; P = <0.001) when compared with lower median levels. Conclusions The results show diurnal patterns of ischemic stroke occurrence based on upper and lower median ozone levels for a 24-hour period, which extends understanding of the association between stroke occurrence and environmental influences. PMID:27015421

  7. Deep venous thrombophlebitis: detection with 4-hour versus 24-hour platelet scintigraphy

    SciTech Connect

    Seabold, J.E.; Conrad, G.R.; Ponto, J.A.; Kimball, D.A.; Frey, E.E.; Ahmed, F.; Coughlan, J.D.; Jensen, K.C.

    1987-11-01

    Thirty-one nonheparinized patients with suspected deep venous thrombophlebitis (DVT) underwent contrast venography and indium-111 platelet scintigraphy (In-111 PS). Venography permitted identification of acute DVT in 12 of 31 cases (39%). One additional patient was considered to have acute DVT despite nonconclusive venography results. In-111 PS results were positive at 4 hours in nine of 13 cases (69%) and at 24 hours in 12 of 13 cases (92%). Two of four patients with false-negative 4-hour In-111 PS studies had received warfarin. Thus, the sensitivity of 4-hour In-111 PS in patients not receiving anticoagulants was 82%. Venography results were negative for acute DVT in 18 cases, and 4-hour In-111 PS studies were negative or equivocal in each. In-111 PS is an alternative to contrast venography for detecting acute DVT. If 4-hour In-111 PS results are positive, anticoagulation can be initiated. Delayed images are necessary if the 4-hour images are negative or equivocal.

  8. Severe community-acquired pneumonia: timely management measures in the first 24 hours.

    PubMed

    Phua, Jason; Dean, Nathan C; Guo, Qi; Kuan, Win Sen; Lim, Hui Fang; Lim, Tow Keang

    2016-01-01

    Mortality rates for severe community-acquired pneumonia (CAP) range from 17 to 48 % in published studies.In this review, we searched PubMed for relevant papers published between 1981 and June 2016 and relevant files. We explored how early and aggressive management measures, implemented within 24 hours of recognition of severe CAP and carried out both in the emergency department and in the ICU, decrease mortality in severe CAP.These measures begin with the use of severity assessment tools and the application of care bundles via clinical decision support tools. The bundles include early guideline-concordant antibiotics including macrolides, early haemodynamic support (lactate measurement, intravenous fluids, and vasopressors), and early respiratory support (high-flow nasal cannulae, lung-protective ventilation, prone positioning, and neuromuscular blockade for acute respiratory distress syndrome).While the proposed interventions appear straightforward, multiple barriers to their implementation exist. To successfully decrease mortality for severe CAP, early and close collaboration between emergency medicine and respiratory and critical care medicine teams is required. We propose a workflow incorporating these interventions. PMID:27567896

  9. A 24-HOUR AMBULATORY ECG MONITORING IN ASSESSMENT OF QT INTERVAL DURATION AND DISPERSION IN ROWERS WITH PHYSIOLOGICAL MYOCARDIAL HYPERTROPHY

    PubMed Central

    Kim, Z.F.; Bilalova, R.R.; Tsibulkin, N.A.; Almetova, R.R.; Mudarisova, R.R.; Ahmetov, I.I.

    2013-01-01

    Myocardial hypertrophy (MH) due to cardiac pathology is characterized by an increase in QT interval duration and dispersion, while the findings for exercise-induced myocardial hypertrophy are contradictory. The majority of published research findings have not explored this relationship, but there have only been a few conducted studies using 24-hour ECG monitoring. The aim of the study was to determine the QT interval duration and dispersion in short-term and 24-hour ECG in endurance athletes with myocardial hypertrophy and without it. Methods: A total of 26 well-trained rowers underwent a resting 12-lead ECG, 24-hour ECG monitoring and echocardiography. Results: Athletes with MH (n = 7) at rest did not show any increase in QTc interval duration and dispersion, or mean and maximal QTc duration in Holter monitoring compared to athletes without MH (n = 19). Left ventricular mass was not significantly correlated with any QTc characteristics. Furthermore, athletes with MH had significantly longer mean QT (P = 0.01) and maximal QT (P = 0.018) intervals in Holter monitoring and higher 24-hour heart rate variability indexes due to stronger vagal effects. Conclusions: The present study demonstrated that athlete's heart syndrome with myocardial hypertrophy as a benign phenomenon does not lead to an increase in QT interval duration, or increases in maximal and mean duration in a 24-hour ECG. An increase in QT interval duration in athletes may have an autonomic nature. PMID:24744494

  10. Gender differences in the relationship between resting heart rate variability and 24-hour blood pressure variability.

    PubMed

    Thayer, Julian F; Sollers, John J; Friedman, Bruce H; Koenig, Julian

    2016-02-01

    The study explored the relationship between time- and frequency-domain indices of cardiac autonomic control and 24 h blood pressure variability (BPV) in a sample of healthy men and women. Vagally mediated cardiac control was inversely related to 24 h BPV, and measures of cardiac autonomic control were better predictors of systolic BPV in men and better predictors of diastolic BPV in women. These findings may help researchers to understand the disparity in cardiovascular disease morbidity and mortality between men and women. PMID:26415550

  11. Usability of a smartphone food picture app for assisting 24-hour dietary recall: a pilot study

    PubMed Central

    Pope, Benjamin T.; Bilgiç, Pelin; Orr, Barron J.; Suzuki, Asuka; Kim, Angela Sarah; Merchant, Nirav C.; Roe, Denise J.

    2015-01-01

    BACKGROUND/OBJECTIVES The Recaller app was developed to help individuals record their food intakes. This pilot study evaluated the usability of this new food picture application (app), which operates on a smartphone with an embedded camera and Internet capability. SUBJECTS/METHODS Adults aged 19 to 28 years (23 males and 22 females) were assigned to use the Recaller app on six designated, nonconsecutive days in order to capture an image of each meal and snack before and after eating. The images were automatically time-stamped and uploaded by the app to the Recaller website. A trained nutritionist administered a 24-hour dietary recall interview 1 day after food images were taken. Participants' opinions of the Recaller app and its usability were determined by a follow-up survey. As an evaluation indicator of usability, the number of images taken was analyzed and multivariate Poisson regression used to model the factors determining the number of images sent. RESULTS A total of 3,315 food images were uploaded throughout the study period. The median number of images taken per day was nine for males and 13 for females. The survey showed that the Recaller app was easy to use, and 50% of the participants would consider using the app daily. Predictors of a higher number of images were as follows: greater interval (hours) between the first and last food images sent, weekend, and female. CONCLUSIONS The results of this pilot study provide valuable information for understanding the usability of the Recaller smartphone food picture app as well as other similarly designed apps. This study provides a model for assisting nutrition educators in their collection of food intake information by using tools available on smartphones. This innovative approach has the potential to improve recall of foods eaten and monitoring of dietary intake in nutritional studies. PMID:25861429

  12. Difference in 24-Hour Urine Composition between Diabetic and Non-Diabetic Adults without Nephrolithiasis

    PubMed Central

    Qin, Jing; Duan, Xiaolu; Liu, Yang; Zhao, Zhijian; Yuan, Jian; Wan, Shaw P.; Zeng, Guohua

    2016-01-01

    Background Diabetic patients are more likely to develop kidney stones than the general population. The underlying mechanisms for this disparity remain to be elucidated. Little is known about the relationship between urine composition and diabetes mellitus in non-stone-forming individuals. We sought to examine the differences in the 24-hour (24-h) urine composition between diabetic and non-diabetic adults who were not stone formers. Methods A convenience sample of 538 individuals without a history of nephrolithiasis, gout, hyperparathyroidism, or gastroenteric diseases participated in this study. The 24-h urine profiles of 115 diabetic adults were compared with those of 423 non-diabetic adults. Diabetes was defined by self-reported physician diagnosis or medication use. All participants were non-stone formers confirmed by urinary tract ultrasonography. Participants provided a fasting blood sample and a single 24-h urine collection for stone risk analysis. Student’s t-test was used to compare mean urinary values. Linear regression models were adjusted for age, gender, body mass index, hypertension, fasting serum glucose, serum total cholesterol, estimated creatinine clearance rate and urinary factors. Results Univariable analysis showed that the diabetic participants had significantly higher 24-h urine volumes and lower urine calcium and magnesium excretions than non-diabetic participants (all P < 0.05). After multivariate adjustment, no significant differences in 24-h urine composition were observed between diabetic and non-diabetic participants except for a slightly increased 24-h urine volume in diabetic participants (all P > 0.05). The main limitation of this study is that the convenience samples and self-reported data may have been sources of bias. Conclusion Our data showed that there were no differences in 24-h urine composition between diabetic and non-diabetic adults who are not stone formers. The reason for it might be the improved glycemic control in

  13. To Compare the Microleakage Among Experimental Adhesives Containing Nanoclay Fillers after the Storages of 24 Hours and 6 Months

    PubMed Central

    Mousavinasab, Seyed Mostafa; Atai, Mohammad; Alavi, Bagher

    2011-01-01

    Objectives: To compare the microleakage among experimental adhesives containing nanoclay fillers after the storages of 24 hours and 6 months. Materials and Methods: Class V cavities were prepared on extracted human molars with the occlusal margins located in enamel and the cervical margins in cementum. Phosphoric acid was applied to the enamel and dentin margins.Subsequently, the cavities were treated using four groups of experimental adhesive systems and restored with a resin composite. Adper Single Bond® was used as control group. After 24- hour and 6- month storages, the samples were subjected to thermocycling shocks and then immersed in silver nitrate as well as developer solution and finally evaluated for leakage. The data were analyzed using SPSS software. Results: Based on Kruskal –Wallis test, significant differences were found between groups regarding microleakage. The Mann- Whitney test showed that Leakage was significantly lower in Adper Single Bond® compared to the other groups in dentinal margins after 24 hours and 6 months and in enamel margins after 6 months. The Wilcoxon Signed Ranks test showed that the enamel leakage in experimental adhesives was significantly lower than dentinal leakage after 24 hours as well as enamel leakage in Adper Single Bond and adhesive with 0.5% PMAA-g-nanoclay was significantly lower than dentinal margins after storage period of 6 months. Conclusion: All the experimental adhesives were effective in reducing enamel leakage after 24 hours, but were not effective in reducing dentinal leakage after 24 hours as well as in enamel and dentinal leakage after a 6-month storage. No improvement was observed in the microleakage in dentin in both short (24 hrs) and long times (6 months). The high microleakage in the adhesives is probably attributed to the high concentration of HEMA in the recipe of the bonding agent. PMID:21566692

  14. Executive Functions are not Affected by 24 Hours of Sleep Deprivation: A Color-Word Stroop Task Study

    PubMed Central

    Dixit, Abhinav; Mittal, Tushar

    2015-01-01

    Background: Sleep is an important factor affecting cognitive performance. Sleep deprivation results in fatigue, lack of concentration, confusion and sleepiness along with anxiety, depression and irritability. Sleep deprivation can have serious consequences in professions like armed forces and medicine where quick decisions and actions need to be taken. Color-Word Stroop task is one of the reliable tests to assess attention and it analyzes the processing of information in two dimensions i.e., reading of words and naming of colour. The evidence regarding the effect of sleep deprivation on Stroop interference is conflicting. The present study evaluated the effect of 24 hours of sleep deprivation on reaction time and interference in Stroop task. Materials and Methods: The present study was done on 30 healthy male medical student volunteers in the age group of 18-25 years after taking their consent and clearance from Institute Ethics Committee. Recordings of Stroop task were at three times: baseline (between 7-9 am), after 12 hours (7-9 pm) and after 24 hours (7-9 am, next day). The subjects were allowed to perform normal daily activities. Results: The study revealed a significant increase in reaction time after 24 hours of sleep deprivation in comparison to baseline and after 12 hours of sleep deprivation. There was no significant change in interference and facilitation after sleep deprivation in comparison to baseline. The number of errors also did not show any significant change after sleep deprivation. Conclusion: The study indicated that there was slowing of responses without change in executive functions after 24 hours of sleep deprivation. It is probable that 24 hours of sleep deprivation does not bring about change in areas of brain affecting executive functions in healthy individuals who have normal sleep cycle. The present study indicated that in professions like armed forces and medicine working 24 hours at a stretch can lead to decrease in motor responses

  15. Resistance training decreases 24-hour blood pressure in women with metabolic syndrome

    PubMed Central

    2013-01-01

    Background The purpose of this study was to verify the effects of eight weeks of resistance training (RT) on 24 hour blood pressure (BP) in patients with and without metabolic syndrome (MetS). Methods Seventeen women volunteered to participate in this study, 9 with MetS (37.0 ± 8.7 yrs; body mass 77.3 ± 9.7 kg; body mass index 30.3 ± 4.2 kg · m-2) and 8 without MetS (35.1 ± 7.2 yrs; body mass 61.3 ± 8.1 kg; body mass index 24.2 ± 2.5 kg · m-2). Individuals were subjected to eight weeks (3 times/week) of whole body RT comprised of one exercise for each main muscle group with three sets of 8–12 repetitions of each subject’s maximal load . A rest interval of one minute was allowed between sets and exercises. Twenty-four hour BP was measured by ambulatory blood pressure monitoring. Results Mean and diastolic night-time BP decreased (−3.9 mmHg, p = 0.04; -5.5 mmHg, p = 0.03, respectively) after eight weeks of training in MetS patients. This decrease was observed at 11:00 pm, 02:00 am (only diastolic), 07:00 am, and 6:00 pm. There was no training effect on BP in women without MetS. Conclusions Considering the elevation of BP as a contributor to the pathogenesis of MetS, and also to the increase of cardiovascular risk, this study supports RT as a non-pharmacological therapy in the management of BP control for MetS. PMID:23711286

  16. Tasimelteon (Hetlioz™): A New Melatonin Receptor Agonist for the Treatment of Non-24-Hour Sleep-Wake Disorder.

    PubMed

    Bonacci, Janene M; Venci, Jineane V; Gandhi, Mona A

    2015-10-01

    In January 2014, the US Food and Drug Administration approved tasimelteon (Hetlioz™), a melatonin-receptor agonist for the treatment of non-24-hour sleep-wake disorder. This article provides an overview of the mechanism of action, pharmacokinetic properties, as well as the clinical efficacy, safety, and tolerability of tasimelteon. Relevant information was identified through a comprehensive literature search of several databases using the key words tasimelteon, Non-24-hour Sleep-Wake disorder, Non-24, and melatonin. Further information was obtained from the tasimelteon package insert, fda.gov, clinicaltrials.gov, briefing materials provided by Vanda Pharmaceuticals, and posters from scientific meetings. PMID:25092604

  17. Characterisation of sleep in intensive care using 24-hour polysomnography: an observational study

    PubMed Central

    2013-01-01

    Introduction Many intensive care patients experience sleep disruption potentially related to noise, light and treatment interventions. The purpose of this study was to characterise, in terms of quantity and quality, the sleep of intensive care patients, taking into account the impact of environmental factors. Methods This observational study was conducted in the adult ICU of a tertiary referral hospital in Australia, enrolling 57 patients. Polysomnography (PSG) was performed over a 24-hour period to assess the quantity (total sleep time: hh:mm) and quality (percentage per stage, duration of sleep episode) of patients' sleep while in ICU. Rechtschaffen and Kales criteria were used to categorise sleep. Interrater checks were performed. Sound pressure and illuminance levels and care events were simultaneously recorded. Patients reported on their sleep quality in ICU using the Richards Campbell Sleep Questionnaire and the Sleep in Intensive Care Questionnaire. Data were summarised using frequencies and proportions or measures of central tendency and dispersion as appropriate and Cohen's Kappa statistic was used for interrater reliability of the sleep data analysis. Results Patients' median total sleep time was 05:00 (IQR: 02:52 to 07:14). The majority of sleep was stage 1 and 2 (medians: 19 and 73%) with scant slow wave and REM sleep. The median duration of sleep without waking was 00:03. Sound levels were high (mean Leq 53.95 dB(A) during the day and 50.20 dB(A) at night) and illuminance levels were appropriate at night (median <2 lux) but low during the day (median: 74.20 lux). There was a median 1.7 care events/h. Patients' mean self-reported sleep quality was poor. Interrater reliability of sleep staging was highest for slow wave sleep and lowest for stage 1 sleep. Conclusions The quantity and quality of sleep in intensive care patients are poor and may be related to noise, critical illness itself and treatment events that disturb sleep. The study highlights the

  18. Self-Renewal and Differentiation Capacity of Urine-Derived Stem Cells after Urine Preservation for 24 Hours

    PubMed Central

    Shi, Yingai; Bharadwaj, Shantaram; Leng, Xiaoyan; Zhou, Xiaobo; Liu, Hong; Atala, Anthony; Zhang, Yuanyuan

    2013-01-01

    Despite successful approaches to preserve organs, tissues, and isolated cells, the maintenance of stem cell viability and function in body fluids during storage for cell distribution and transportation remains unexplored. The aim of this study was to characterize urine-derived stem cells (USCs) after optimal preservation of urine specimens for up to 24 hours. A total of 415 urine specimens were collected from 12 healthy men (age range 20–54 years old). About 6×104 cells shed off from the urinary tract system in 24 hours. At least 100 USC clones were obtained from the stored urine specimens after 24 hours and maintained similar biological features to fresh USCs. The stored USCs had a “rice grain” shape in primary culture, and expressed mesenchymal stem cell surface markers, high telomerase activity, and normal karyotypes. Importantly, the preserved cells retained bipotent differentiation capacity. Differentiated USCs expressed myogenic specific proteins and contractile function when exposed to myogenic differentiation medium, and they expressed urothelial cell-specific markers and barrier function when exposed to urothelial differentiation medium. These data demonstrated that up to 75% of fresh USCs can be safely persevered in urine for 24 hours and that these cells stored in urine retain their original stem cell properties, indicating that preserved USCs could be available for potential use in cell-based therapy or clinical diagnosis. PMID:23349776

  19. Accuracy and Usefulness of Select Methods for Assessing Complete Collection of 24-Hour Urine: A Systematic Review.

    PubMed

    John, Katherine A; Cogswell, Mary E; Campbell, Norm R; Nowson, Caryl A; Legetic, Branka; Hennis, Anselm J M; Patel, Sheena M

    2016-05-01

    Twenty-four-hour urine collection is the recommended method for estimating sodium intake. To investigate the strengths and limitations of methods used to assess completion of 24-hour urine collection, the authors systematically reviewed the literature on the accuracy and usefulness of methods vs para-aminobenzoic acid (PABA) recovery (referent). The percentage of incomplete collections, based on PABA, was 6% to 47% (n=8 studies). The sensitivity and specificity for identifying incomplete collection using creatinine criteria (n=4 studies) was 6% to 63% and 57% to 99.7%, respectively. The most sensitive method for removing incomplete collections was a creatinine index <0.7. In pooled analysis (≥2 studies), mean urine creatinine excretion and volume were higher among participants with complete collection (P<.05); whereas, self-reported collection time did not differ by completion status. Compared with participants with incomplete collection, mean 24-hour sodium excretion was 19.6 mmol higher (n=1781 specimens, 5 studies) in patients with complete collection. Sodium excretion may be underestimated by inclusion of incomplete 24-hour urine collections. None of the current approaches reliably assess completion of 24-hour urine collection. PMID:26726000

  20. Population Pharmacokinetic Model Characterizing 24-Hour Variation in the Pharmacokinetics of Oral and Intravenous Midazolam in Healthy Volunteers

    PubMed Central

    van Rongen, A; Kervezee, L; Brill, MJE; van Meir, H; den Hartigh, J; Guchelaar, H-J; Meijer, JH; Burggraaf, J; van Oosterhout, F

    2015-01-01

    Daily rhythms in physiology may affect the pharmacokinetics of a drug. The aim of this study was to evaluate 24-hour variation in the pharmacokinetics of the CYP3A substrate midazolam. Oral (2 mg) and intravenous (1 mg) midazolam was administered at six timepoints throughout the 24-hour period in 12 healthy volunteers. Oral bioavailability (population mean value [RSE%] of 0.28 (7.1%)) showed 24-hour variation that was best parameterized as a cosine function with an amplitude of 0.04 (17.3%) and a peak at 12:14 in the afternoon. The absorption rate constant was 1.41 (4.7%) times increased after drug administration at 14:00. Clearance (0.38 L/min (4.8%)) showed a minor 24-hour variation with an amplitude of 0.03 (14.8%) L/min and a peak at 18:50. Simulations show that dosing time minimally affects the concentration time profiles after intravenous administration, while concentrations are higher during the day compared to the night after oral dosing, reflecting considerable variation in intestinal processes. PMID:26380154

  1. Population Pharmacokinetic Model Characterizing 24-Hour Variation in the Pharmacokinetics of Oral and Intravenous Midazolam in Healthy Volunteers.

    PubMed

    van Rongen, A; Kervezee, L; Brill, Mje; van Meir, H; den Hartigh, J; Guchelaar, H-J; Meijer, J H; Burggraaf, J; van Oosterhout, F

    2015-08-01

    Daily rhythms in physiology may affect the pharmacokinetics of a drug. The aim of this study was to evaluate 24-hour variation in the pharmacokinetics of the CYP3A substrate midazolam. Oral (2 mg) and intravenous (1 mg) midazolam was administered at six timepoints throughout the 24-hour period in 12 healthy volunteers. Oral bioavailability (population mean value [RSE%] of 0.28 (7.1%)) showed 24-hour variation that was best parameterized as a cosine function with an amplitude of 0.04 (17.3%) and a peak at 12:14 in the afternoon. The absorption rate constant was 1.41 (4.7%) times increased after drug administration at 14:00. Clearance (0.38 L/min (4.8%)) showed a minor 24-hour variation with an amplitude of 0.03 (14.8%) L/min and a peak at 18:50. Simulations show that dosing time minimally affects the concentration time profiles after intravenous administration, while concentrations are higher during the day compared to the night after oral dosing, reflecting considerable variation in intestinal processes. PMID:26380154

  2. Value of 24-hour Delayed Film of Barium Enema for Evaluation of Colon Transit Function in Young Children with Constipation

    PubMed Central

    Yoo, Ha Yeong; Son, Jae Sung; Park, Hye Won; Kwak, Byung Ok; Kim, Hyeong Su; Bae, Sun Hwan

    2016-01-01

    Background/Aims A colon transit time test using radio-opaque markers (CTTRM) is considered the gold standard for evaluating colon transit function. A 24-hour delayed film of barium enema (BE) has been used as a supplementary method in structural evaluations. The aim of this study was to evaluate the utility of a 24-hour delayed BE film for assessing colon transit function in young children with constipation. Methods In total, 93 children with constipation who performed both single-contrast BE and CTTRM were enrolled in this study. Of these, the data from 70 children were analyzed (males 33, females 37; mean age [range], 5.63 ± 2.94 [2–14] years). The basic principle of the study is “velocity = distance/time”. Time values were identified in both studies, and the colon length and distance of barium movement were measured on the 24-hour delayed BE film. Thus, colon transit velocity values could be calculated using both methods. The correlation between colon transit velocity using a 24-hour delayed BE film versus CTTRM was analyzed statistically. Results Median value (interquartile range) of colon transit velocity using CTTRM was 1.57 (1.07–2.89) cm/hr, and that using BE of that was 1.58 (0.94–2.07) cm/hr. The Spearman correlation coefficient was 0.438 (P < 0.001) for the overall group. The correlation was strongest in children younger than 4 years (r = 0.537, P = 0.032). Conclusions Although the correlation between BE and CTTRM was not very strong, the 24-hour delayed BE film could provide broad information about colon transit function in young children, especially those under 4 years who usually cannot undergo CTTRM. PMID:26979249

  3. Microleakage of Two Self-Adhesive Cements in the Enamel and Dentin After 24 Hours and Two Months

    PubMed Central

    Jaberi Ansari, Zahra; Kalantar Motamedi, Mojdeh

    2014-01-01

    Objective: Microleakage is a main cause of restorative treatment failure. In this study, we compared occlusal and cervical microleakage of two self-adhesive cements after 24 hours and two months. Materials and Methods: In this in-vitro experimental study, class II inlay cavities were prepared on 60 sound human third molars. Composite inlays were fabricated with Z100 composite resin. The teeth were randomly assigned to six groups. RelyX-Arc (control), RelyX-Unicem and Maxcem were used for the first three groups and specimens were stored in distilled water at 37°C for 24 hours. The same cements were used for the remaining three groups, but the specimens were stored for 2 months. The teeth were subjected to 500 thermal cycles (5°C and 55°C) and immersed in 0.5% basic fuchsin for 24 hours and then sectioned mesiodistally and dye penetration was evaluated in a class II cavity with occlusal and cervical margins using X20 magnification stereomicroscope. Data were analyzed using Kruskal Wallis and Mann-Whitney U tests. Results: After 24 hours, cements had significant differences only in cervical margin microleakage (P=0.0001) and microleakage of RelyX-Unicem and Maxcem was significantly more than that of RelyX-Arc (both P=0.0001). Cervical microleakage in RelyX-Unicem and Maxcem was greater than occlusal (P=0.0001 and P=0.001, respectively). Microleakage was not significantly different between the occlusal and cervical margins after 2 months. Conclusion: Cervical microleakage was greater than occlusal in RelyX-Unicem and Maxcem after 24h. The greatest microleakage was reported for the cervical margin of RelyX-Unicem after 24 hours. PMID:25584053

  4. Changes in platelet morphology and function during 24 hours of storage.

    PubMed

    Braune, S; Walter, M; Schulze, F; Lendlein, A; Jung, F

    2014-01-01

    aggregates could be visualized microscopically. After four hours, first debris and very small aggregates occurred. After 24 hours, platelet aggregates and also debris progressively increased. In accordance to this, the CASY system revealed an increase of platelet aggregates (up to 90 μm diameter) with increasing storage time. The percentage of CD62P positive platelets and PF4 increased significantly with storage time in resting PRP. When soluble ADP was added to stored PRP samples, the number of activatable platelets decreased significantly over storage time. The present study reveals the importance of a consequent standardization in the preparation of WB and PRP. Platelet morphology and function, particularly platelet reactivity to adherent or soluble agonists in their surrounding milieu, changed rapidly outside the vascular system. This knowledge is of crucial interest, particularly in the field of biomaterial development for cardiovascular applications, and may help to define common standards in the in vitro hemocompatibility testing of biomaterials. PMID:25227196

  5. Irregular 24-hour Activity Rhythms and the Metabolic Syndrome in Older Adults

    PubMed Central

    Sohail, Shahmir; Yu, Lei; Bennett, David A.; Buchman, Aron S.; Lim, Andrew S.P.

    2015-01-01

    Circadian rhythms – near 24-hour intrinsic biological rhythms – modulate many aspects of human physiology and hence disruption of circadian rhythms may have an important impact on human health. Experimental work supports a potential link between irregular circadian rhythms and several key risk factors for cardiovascular disease including hypertension, obesity, diabetes, and dyslipidemia, collectively termed the metabolic syndrome. While several epidemiological studies have demonstrated an association between shift-work and the components of the metabolic syndrome in working-age adults, there is a relative paucity of data concerning the impact of non-occupational circadian irregularity in older women and men. To address this question, we studied 7 days of actigraphic data from 1137 older woman and men participating in the Rush Memory and Aging Project, a community-based cohort study of the chronic conditions of aging. The regularity of activity rhythms was quantified using the nonparametric interdaily stability metric, and was related to the metabolic syndrome and its components obesity, hypertension, diabetes, and dyslipidemia. More regular activity rhythms were associated with a lower odds of having the metabolic syndrome (OR=0.69, 95%CI=0.60–0.80, p=5.8×10−7), being obese (OR=0.73, 95%CI=0.63–0.85, p=2.5×10−5), diabetic (OR=0.76, 95%CI=0.65–0.90, p=9.3×10−4), hypertensive (OR=0.78, 95%CI=0.66–0.91, p=2.0×10−3), or dyslipidemic (OR=0.82, 95%CI=0.72–0.92, p=1.2×10−3). These associations were independent of differences in objectively measured total daily physical activity or rest, and were not accounted for by prevalent coronary artery disease, stroke, or peripheral artery disease. Moreover, more regular activity rhythms were associated with lower odds of having cardiovascular disease (OR=0.83; 95%CI=0.73–0.95, p=5.7×10−3), an effect that was statistically mediated by the metabolic syndrome. We conclude that irregular activity

  6. Invasively Measured Aortic Systolic Blood Pressure and Office Systolic Blood Pressure in Cardiovascular Risk Assessment: A Prospective Cohort Study.

    PubMed

    Laugesen, Esben; Knudsen, Søren T; Hansen, Klavs W; Rossen, Niklas B; Jensen, Lisette Okkels; Hansen, Michael G; Munkholm, Henrik; Thomsen, Kristian K; Søndergaard, Hanne; Bøttcher, Morten; Raungaard, Bent; Madsen, Morten; Hulman, Adam; Witte, Daniel; Bøtker, Hans Erik; Poulsen, Per L

    2016-09-01

    Aortic systolic blood pressure (BP) represents the hemodynamic cardiac and cerebral burden more directly than office systolic BP. Whether invasively measured aortic systolic BP confers additional prognostic value beyond office BP remains debated. In this study, office systolic BP and invasively measured aortic systolic BP were recorded in 21 908 patients (mean age: 63 years; 58% men; 14% with diabetes mellitus) with stable angina pectoris undergoing elective coronary angiography during January 2001 to December 2012. Multivariate Cox models were used to assess the association with incident myocardial infarction, stroke, and death. Discrimination and reclassification were assessed using Harrell's C and the Continuous Net Reclassification Index. Data were analyzed with and without stratification by diabetes mellitus status. During a median follow-up period of 3.7 years (range: 0.1-10.8 years), 422 strokes, 511 myocardial infarctions, and 1530 deaths occurred. Both office and aortic systolic BP were associated with stroke in patients with diabetes mellitus (hazard ratio per 10 mm Hg, 1.18 [95% confidence interval, 1.07-1.30] and 1.14 [95% confidence interval, 1.05-1.24], respectively) and with myocardial infarction in patients without diabetes mellitus (hazard ratio, 1.07 [95% confidence interval, 1.02-1.12] and 1.05 [95% confidence interval, 1.01-1.10], respectively). In models including both BP measurements, aortic BP lost statistical significance and aortic BP did not confer improvement in either C-statistics or net reclassification analysis. In conclusion, invasively measured aortic systolic BP does not add prognostic information about cardiovascular outcomes and all-cause mortality compared with office BP in patients with stable angina pectoris, either with or without diabetes mellitus. PMID:27402917

  7. Changes in foot volume, body composition, and hydration status in male and female 24-hour ultra-mountain bikers

    PubMed Central

    2014-01-01

    Background The effects of running and cycling on changes in hydration status and body composition during a 24-hour race have been described previously, but data for 24-hour ultra-mountain bikers are missing. The present study investigated changes in foot volume, body composition, and hydration status in male and female 24-hour ultra-mountain bikers. Methods We compared in 49 (37 men and 12 women) 24-hour ultra-mountain bikers (ultra-MTBers) changes (Δ) in body mass (BM). Fat mass (FM), percent body fat (%BF) and skeletal muscle mass (SM) were estimated using anthropometric methods. Changes in total body water (TBW), extracellular fluid (ECF) and intracellular fluid (ICF) were determined using bioelectrical impedance and changes in foot volume using plethysmography. Haematocrit, plasma [Na+], plasma urea, plasma osmolality, urine urea, urine specific gravity and urine osmolality were measured in a subgroup of 25 ultra-MTBers (16 men and 9 women). Results In male 24-hour ultra-MTBers, BM (P < 0.001), FM (P < 0.001), %BF (P < 0.001) and ECF (P < 0.05) decreased whereas SM and TBW did not change (P > 0.05). A significant correlation was found between post-race BM and post-race FM (r = 0.63, P < 0.001). In female ultra-MTBers, BM (P < 0.05), %BF (P < 0.05) and FM (P < 0.001) decreased, whereas SM, ECF and TBW remained stable (P > 0.05). Absolute ranking in the race was related to Δ%BM (P < 0.001) and Δ%FM in men (P < 0.001) and to Δ%BM (P < 0.05) in women. In male ultra-MTBers, increased post-race plasma urea (P < 0.001) was negatively related to absolute ranking in the race, Δ%BM, post-race FM and Δ%ECF (P < 0.05). Foot volume remained stable in both sexes (P > 0.05). Conclusions Male and female 24-hour ultra-MTBers experienced a significant loss in BM and FM, whereas SM remained stable. Body weight changes and increases in plasma urea do not reflect a change in body hydration status. No oedema

  8. Reasoning about systolic algorithms

    SciTech Connect

    Purushothaman, S.

    1986-01-01

    Systolic algorithms are a class of parallel algorithms, with small grain concurrency, well suited for implementation in VLSI. They are intended to be implemented as high-performance, computation-bound back-end processors and are characterized by a tesselating interconnection of identical processing elements. This dissertation investigates the problem of providing correctness of systolic algorithms. The following are reported in this dissertation: (1) a methodology for verifying correctness of systolic algorithms based on solving the representation of an algorithm as recurrence equations. The methodology is demonstrated by proving the correctness of a systolic architecture for optimal parenthesization. (2) The implementation of mechanical proofs of correctness of two systolic algorithms, a convolution algorithm and an optimal parenthesization algorithm, using the Boyer-Moore theorem prover. (3) An induction principle for proving correctness of systolic arrays which are modular. Two attendant inference rules, weak equivalence and shift transformation, which capture equivalent behavior of systolic arrays, are also presented.

  9. Food Intake Recording Software System, version 4 (FIRSSt4): A Self-Completed 24 Hour Dietary Recall for Children

    PubMed Central

    Baranowski, Tom; Islam, Noemi; Douglass, Deirdre; Dadabhoy, Hafza; Beltran, Alicia; Baranowski, Janice; Thompson, Debbe; Cullen, Karen W.; Subar, Amy F.

    2012-01-01

    The Food Intake Recording Software System, version 4(FIRSSt4), is a web-based 24 hour dietary recall (24hdr) self-administered by children based on the Automated Self-Administered 24-hour recall (ASA24) (a self-administered 24hdr for adults). The food choices in FIRSST4 are abbreviated to include only those reported by children in U.S. national surveys; and detailed food probe questions are simplified to exclude those that children could not be expected to answer (for example questions regarding food preparation and added fats). ASA24 and FIRSSt4 incorporate 10,000+ food images with up to eight images per food to assist in portion size estimation. This paper reviews the formative research conducted during the development of FIRSSt4. When completed, FIRSSt4 will be hosted and maintained for investigator use on the National Cancer Institute’s ASA24 website. PMID:22616645

  10. Dipstick Spot urine pH does not accurately represent 24 hour urine PH measured by an electrode

    PubMed Central

    Omar, Mohamed; Sarkissian, Carl; Jianbo, Li; Calle, Juan; Monga, Manoj

    2016-01-01

    ABSTRACT Objectives To determine whether spot urine pH measured by dipstick is an accurate representation of 24 hours urine pH measured by an electrode. Materials and Methods We retrospectively reviewed urine pH results of patients who presented to the urology stone clinic. For each patient we recorded the most recent pH result measured by dipstick from a spot urine sample that preceded the result of a 24-hour urine pH measured by the use of a pH electrode. Patients were excluded if there was a change in medications or dietary recommendations or if the two samples were more than 4 months apart. A difference of more than 0.5 pH was considered an inaccurate result. Results A total 600 patients were retrospectively reviewed for the pH results. The mean difference in pH between spot urine value and the 24 hours collection values was 0.52±0.45 pH. Higher pH was associated with lower accuracy (p<0.001). The accuracy of spot urine samples to predict 24-hour pH values of <5.5 was 68.9%, 68.2% for 5.5 to 6.5 and 35% for >6.5. Samples taken more than 75 days apart had only 49% the accuracy of more recent samples (p<0.002). The overall accuracy is lower than 80% (p<0.001). Influence of diurnal variation was not significant (p=0.588). Conclusions Spot urine pH by dipstick is not an accurate method for evaluation of the patients with urolithiasis. Patients with alkaline urine are more prone to error with reliance on spot urine pH. PMID:27286119

  11. 24-hour evaluation of dental plaque bacteria and halitosis after consumption of a single placebo or dental treat by dogs.

    PubMed

    Jeusette, Isabelle C; Román, Aurora Mateo; Torre, Celina; Crusafont, Josep; Sánchez, Nuria; Sánchez, Maria C; Pérez-Salcedo, Leire; Herrera, David

    2016-06-01

    OBJECTIVE To determine whether consumption of a single dental treat with specific mechanical properties and active ingredients would provide a 24-hour effect on dental plaque bacteria and halitosis in dogs. ANIMALS 10 dogs of various breeds from a privately owned colony that had received routine dental scaling and polishing 4 weeks before the study began. PROCEDURES Dogs were randomly assigned to receive 1 placebo or dental treat first. A 4-week washout period was provided, and then dogs received the opposite treatment. Oral plaque and breath samples were collected before and 0.5, 3, 12, and 24 hours after treat consumption. Volatile sulfur compounds (VSCs) concentration was measured in breath samples. Total aerobic, total anaerobic, Porphyromonas gulae, Prevotella intermedia-like, Tannerella forsythia, and Fusobacterium nucleatum bacterial counts (measured via bacterial culture) and total live bacterial counts, total live and dead bacterial counts, and bacterial vitality (measured via quantitative real-time PCR assay) were assessed in plaque samples. RESULTS Compared with placebo treat consumption, dental treat consumption resulted in a significant decrease in breath VSCs concentration and all plaque bacterial counts, without an effect on bacterial vitality. Effects of the dental treat versus the placebo treat persisted for 12 hours for several bacterial counts and for 24 hours for breath VSCs concentration. CONCLUSIONS AND CLINICAL RELEVANCE Although clinical benefits should be investigated in larger scale, longer-term studies, results of this study suggested that feeding the evaluated dental treat may help to decrease oral bacterial growth in dogs for 12 hours and oral malodor for 24 hours. A feeding interval of 12 hours is therefore recommended. PMID:27227499

  12. Reliability and Predictive Validity of Caloric Intake Measures from the 24-Hour Dietary Recalls of Homebound Older Adults

    PubMed Central

    Sun, Yanhui; Roth, David L.; Ritchie, Christine S.; Burgio, Kathryn L.; Locher, Julie L.

    2010-01-01

    24-hour dietary recalls are used frequently to study homebound older adults’ eating behaviors. However, the reliability and predictive validity of this method have not been established in this population. The purpose of this study is to examine whether homebound older adults provide reliable and valid measures of total caloric intake in 24-hour dietary recalls. 230 homebound older adults were interviewed in their homes using a questionnaire to assess eating behaviors and factors that could affect those behaviors. Participants completed three 24-hour dietary recalls at baseline and again at 6-month follow-up. Two sub-samples were identified for analyses. For participants who were not hospitalized during the 6-month interval and had their weight measured at both assessments (n = 52), sufficient test-retest reliability of caloric intake was observed (r = 0.59); but caloric intake deficiencies relative to estimated energy requirements did not predict actual weight loss (r = 0.08). When this sample was supplemented with 91 participants who experienced any adverse event (weight loss of 2.5% or more, hospitalization, institutionalization, or mortality) in the 6-month period (n = 143), adverse events were more likely to occur for those with insufficient caloric intake (odds ratio = 3.49, p = .009), and in White participants compared to African American participants (odds ratio = 3.13, p=0.016). Adequate test-retest reliability of the 24-hour dietary recall was demonstrated, but additional research with larger samples and longer follow-up intervals are needed to better evaluate the predictive validity of caloric intake measures for this population. PMID:20430140

  13. HOW RELIABLE IS 24 HOUR SERUM LITHIUM LEVEL AFTER A TEST DOSE OF LITHIUM IN PREDICTING OPTIMAL LITHIUM DOSE?

    PubMed Central

    Kuruvilla, K.; Shaji, K.S.

    1989-01-01

    SUMMARY 57% of a group of 35 patients treated with Lithium Carbonate at dosages predicted by the nomogram suggested by Cooper et al (1973) failed to reach therapeutic levels of serum lithium. This finding casts serious doubts on the usefulness of the claim by Cooper et al (1973 & 1976) that 24 hour serum lithium level after a test dose of 600 mg. lithium can predict the daily lithium dose. PMID:21927360

  14. Comparing food intake using the Dietary Risk Assessment with multiple 24-hour dietary recalls and the 7-Day Dietary Recall.

    PubMed

    Olendzki, B; Hurley, T G; Hebert, J R; Ellis, S; Merriam, P A; Luippold, R; Rider, L; Ockene, I S

    1999-11-01

    The Dietary Risk Assessment (DRA) is a brief dietary assessment tool used to identify dietary behaviors associated with cardiovascular disease. Intended for use by physicians and other nondietitians, the DRA identifies healthful and problematic dietary behaviors and alerts the physician to patients who require further nutrition counseling. To determine the relative validity of this tool, we compared it to the 7-Day Dietary Recall (an instrument developed to assess intake of dietary fat) and to the average of 7 telephone-administered 24-hour dietary recalls. Forty-two free-living subjects were recruited into the study. The 7-Day Dietary Recall and DRA were administered to each subject twice, at the beginning and the end of the study period, and the 24-hour recalls were conducted during the intervening time period. Correlation coefficients were computed to compare the food scores derived from the 3 assessment methods. Correlations between the DRA and 7-Day Dietary Recall data were moderate (r = .47, on average, for postmeasures); correlations between the DRA and 24-hour recalls were lower. The ability of the DRA to assess dietary fat consumption and ease of administration make it a clinically useful screening instrument for the physician when counseling patients about dietary fat reduction. PMID:10570682

  15. Flow cytometric comparison of platelets from a whole blood and finger-prick sample: impact of 24 hours storage.

    PubMed

    Swanepoel, Albe C; Stander, Andre; Pretorius, Etheresia

    2013-03-01

    In this study, we investigate the validity and laboratory utility of flow cytometry when analyzing platelet activation by studying CD41, CD42b, CD62P and CD63. We compare flow cytometry results from citrated whole-blood and finger-prick samples directly after collection and also after storing both a finger-prick and whole-blood sample for 24 hours. Citrated whole-blood and finger-prick samples were taken from three healthy individuals on two occasions, and a total of 60,000 cells were analyzed for each of the four phycoerythrin-labeled monoclonal antibodies. Half of each sample was analyzed immediately after sampling while the other half was kept in the fridge at 6 °C for 24 hours before analysis. No significant difference was found between the sampling methods or the period of time before analysis. Results therefore suggest that an appropriately prepared finger-prick sample can be used for platelet function analysis, and samples can be stored for 24 hours in the fridge at 6 °C before analysis. PMID:23320994

  16. Assessment of 24-hours Aldosterone Administration on Protein Abundances in Fluorescence-Sorted Mouse Distal Renal Tubules by Mass Spectrometry

    PubMed Central

    Jensen, Thomas B; Pisitkun, Trairak; Hoffert, Jason D; Jensen, Uffe B; Fenton, Robert A; Praetorius, Helle A; Knepper, Mark A; Praetorius, Jeppe

    2013-01-01

    Background/Aims Aldosterone exerts multiple long-term effects in the distal renal tubules. The aim of this study was to establish a method for identifying proteins in these tubules that change in abundance by only 24-hours aldosterone administration. Methods Mice endogenously expressing green fluorescent protein (eGFP) in the connecting tubule and cortical collecting ducts were treated with a subcutaneous injection of 2.0 mg/kg aldosterone or vehicle (n=5), and sacrificed 24 hours later. Suspensions of single cells were obtained enzymatically, and eGFP positive cells were isolated by fluorescence activated cell sorting (FACS). Samples of 100 μg proteins were digested with trypsin and labeled with 8-plex iTRAQ reagents and processed for liquid chromatography tandem mass spectrometry (LC-MS/MS). Results FACS yielded 1.4 million cells per mouse. The LC-MS/MS spectra were matched to peptides by the SEQUEST search algorithm, which identified 3002 peptides corresponding to 506 unique proteins of which 20 significantly changed abundance 24-hours after aldosterone injection. Conclusion We find the method suitable and useful for studying hormonal effects on protein abundance in distal tubular segments. PMID:23428628

  17. Reasoning about systolic algorithms

    SciTech Connect

    Purushothaman, S.; Subrahmanyam, P.A.

    1988-12-01

    The authors present a methodology for verifying correctness of systolic algorithms. The methodology is based on solving a set of Uniform Recurrence Equations obtained from a description of systolic algorithms as a set of recursive equations. They present an approach to mechanically verify correctness of systolic algorithms, using the Boyer-Moore theorem proven. A mechanical correctness proof of an example from the literature is also presented.

  18. The Automated Self-Administered 24-Hour Dietary Recall for Children, 2012 version, for youth aged 9 to 11 Years: A validation study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our objective was to validate the 2012 version of the Automated Self-Administered 24-Hour Dietary Recall for Children (ASA24-Kids-2012), a self-administered web-based 24-hour dietary recall (24hDR) instrument, among children aged 9 to 11 years, in two sites using a quasiexperimental design. In one s...

  19. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR CLEANING: 24 HOUR FOOD DIARY (HAND ENTRY) (UA-D-40.0)

    EPA Science Inventory

    The purpose of the SOP is to define the particular steps involved in cleaning the electronic data generated from data entry of the 24 Hour Food Diary. The procedure was developed to use during the Arizona NHEXAS project and the "Border" study. Keywords: data; cleaning; 24 hour ...

  20. Arrhythmias Seen in Baseline 24-Hour Holter ECG Recordings in Healthy Normal Volunteers During Phase 1 Clinical Trials.

    PubMed

    Hingorani, Pooja; Karnad, Dilip R; Rohekar, Prashant; Kerkar, Vaibhav; Lokhandwala, Yash Y; Kothari, Snehal

    2016-07-01

    Regulatory agencies encourage sponsors to submit 24-hour ambulatory ECG data for assessing cardiac safety of new drugs, and some arrhythmias, hitherto considered rare, have been observed in some early-phase studies. Interpretation of these observations is difficult given the dearth of published data on the prevalence of cardiac arrhythmias seen during 24-hour continuous ECG monitoring in healthy volunteers (HV) from clinical trials. We analyzed drug-free ambulatory ECG recordings from 1273 HV (1000 males, 273 females; age 18-65 years) from 22 phase 1 studies that were analyzed in a core ECG laboratory; all subjects had normal screening ECGs. Supraventricular arrhythmias such as supraventricular premature complexes were observed in 60.8% of healthy volunteers, supraventricular tachycardia in 2.2%, and atrial fibrillation in 0.1%. Ventricular arrhythmias included premature ventricular complexes (PVCs) in 43.4%, >200 PVCs per 24 hours in 3.3%, multifocal PVCs in 5.3%, nonsustained ventricular tachycardia in 0.7%, and accelerated idioventricular rhythm in 0.3%. Bradyarrhythmias included sinus pause >3 seconds in 0.3%, and second-degree AV block in 2.4%. Complete heart block and torsades de pointes were not seen in any subject. Based on the observed incidence, we estimated the maximum number of healthy subjects in whom these arrhythmias may be seen as a matter of chance in studies with smaller sample sizes if the study drug has no arrhythmogenic effect. Our results and these estimates could help interpret whether cardiac arrhythmias observed in early-phase studies are due to chance or possibly are a drug effect. PMID:26626443

  1. Developing a Method to Test the Validity of 24 Hour Time Use Diaries Using Wearable Cameras: A Feasibility Pilot

    PubMed Central

    Kelly, Paul; Thomas, Emma; Doherty, Aiden; Harms, Teresa; Burke, Órlaith; Gershuny, Jonathan; Foster, Charlie

    2015-01-01

    Self-report time use diaries collect a continuous sequenced record of daily activities but the validity of the data they produce is uncertain. This study tests the feasibility of using wearable cameras to generate, through image prompted interview, reconstructed 'near-objective' data to assess their validity. 16 volunteers completed the Harmonised European Time Use Survey (HETUS) diary and used an Autographer wearable camera (recording images at approximately 15 second intervals) for the waking hours of the same 24-hour period. Participants then completed an interview in which visual images were used as prompts to reconstruct a record of activities for comparison with the diary record. 14 participants complied with the full collection protocol. We compared time use and number of discrete activities from the diary and camera records (using 10 classifications of activity). In terms of aggregate totals of daily time use we found no significant difference between the diary and camera data. In terms of number of discrete activities, participants reported a mean of 19.2 activities per day in the diaries, while image prompted interviews revealed 41.1 activities per day. The visualisations of the individual activity sequences reveal some potentially important differences between the two record types, which will be explored at the next project stage. This study demonstrates the feasibility of using wearable cameras to reconstruct time use through image prompted interview in order to test the concurrent validity of 24-hour activity time-use budgets. In future we need a suitably powered study to assess the validity and reliability of 24-hour time use diaries. PMID:26633807

  2. Axial Diffusivity of the Corona Radiata at 24 Hours Post-Stroke: A New Biomarker for Motor and Global Outcome.

    PubMed

    Moulton, Eric; Amor-Sahli, Mélika; Perlbarg, Vincent; Pires, Christine; Crozier, Sophie; Galanaud, Damien; Valabregue, Romain; Yger, Marion; Baronnet-Chauvet, Flore; Samson, Yves; Dormont, Didier; Rosso, Charlotte

    2015-01-01

    Fractional anisotropy (FA) is an effective marker of motor outcome at the chronic stage of stroke yet proves to be less efficient at early time points. This study aims to determine which diffusion metric in which location is the best marker of long-term stroke outcome after thrombolysis with diffusion tensor imaging (DTI) at 24 hours post-stroke. Twenty-eight thrombolyzed patients underwent DTI at 24 hours post-stroke onset. Ipsilesional and contralesional FA, mean (MD), axial (AD), and radial (RD) diffusivities values were calculated in different Regions-of-Interest (ROIs): (1) the white matter underlying the precentral gyrus (M1), (2) the corona radiata (CoRad), (3) the posterior limb of the internal capsule (PLIC) and (4) the cerebral peduncles (CP). NIHSS scores were acquired at admission, day 1, and day 7; modified Rankin Scores (mRS) at 3 months. Significant decreases were found in FA, MD, and AD of the ipsilesional CoRad and M1. MD and AD were also significantly lower in the PLIC. The ratio of ipsi and contralesional AD of the CoRad (CoRad-rAD) was the strongest diffusion parameter correlated with motor NIHSS scores on day 7 and with the mRS at 3 months. A Receiver-Operator Curve analysis yielded a model for the CoRad-rAD to predict good outcome based on upper limb NIHSS motor scores and mRS with high specificity and sensitivity. FA values were not correlated with clinical outcome. In conclusion, axial diffusivity of the CoRad from clinical DTI at 24 hours post-stroke is the most appropriate diffusion metric for quantifying stroke damage to predict outcome, suggesting the importance of early axonal damage. PMID:26562509

  3. Caffeine does not entrain the circadian clock but improves daytime alertness in blind patients with non-24-hour rhythms

    PubMed Central

    St. Hilaire, Melissa A.; Lockley, Steven W.

    2015-01-01

    Objective/Background Totally blind individuals are highly likely to suffer from Non-24-Hour Sleep-Wake Disorder due to a failure of light to reset the circadian pacemaker in the suprachiasmatic nuclei. In this outpatient case series, we investigated whether daily caffeine administration could entrain the circadian pacemaker in non-entrained blind patients to alleviate symptoms of non-24-hour sleep–wake disorder. Patients/Methods Three totally blind males (63.0 ± 7.5 years old) were studied at home over ~4 months. Urinary 6-sulphatoxymelatonin (aMT6s) rhythms were measured for 48 h every 1–2 weeks. Participants completed daily sleep–wake logs, and rated their alertness and mood using nine-point scales every ~2–4 h while awake on urine sampling days. Caffeine capsules (150 mg per os) were self-administered daily at 10 a.m. for approximately one circadian beat cycle based on each participant's endogenous circadian period τ and compared to placebo (n = 2) or no treatment (n = 1) in a single-masked manner. Results Non-24-h aMT6s rhythms were confirmed in all three participants (τ range = 24.32–24.57 h). Daily administration of 150 mg caffeine did not entrain the circadian clock. Caffeine treatment significantly improved daytime alertness at adverse circadian phases (p < 0.0001) but did not decrease the occurrence of daytime naps compared with placebo. Conclusions Although caffeine was able to improve daytime alertness acutely and may therefore provide temporary symptomatic relief, the inability of caffeine to correct the underlying circadian disorder means that an entraining agent is required to treat Non-24-Hour Sleep–Wake Disorder in the blind appropriately. PMID:25891543

  4. The Relationship Between 24-Hour Symptoms and COPD Exacerbations and Healthcare Resource Use: Results from an Observational Study (ASSESS).

    PubMed

    Miravitlles, Marc; Worth, Heinrich; Soler-Cataluña, Juan José; Price, David; De Benedetto, Fernando; Roche, Nicolas; Godtfredsen, Nina S; van der Molen, Thys; Löfdahl, Claes-Göran; Padullés, Laura; Ribera, Anna

    2016-10-01

    This observational study assessed the relationship between nighttime, early-morning and daytime chronic obstructive pulmonary disease (COPD) symptoms and exacerbations and healthcare resource use. COPD symptoms were assessed at baseline in patients with stable COPD using a standardised questionnaire during routine clinical visits. Information was recorded on exacerbations and healthcare resource use during the year before baseline and during a 6-month follow-up period. The main objective of the analysis was to determine the predictive nature of current symptoms for future exacerbations and healthcare resource use. 727 patients were eligible (65.8% male, mean age: 67.2 years, % predicted forced expiratory volume in 1 second: 52.8%); 698 patients (96.0%) provided information after 6 months. Symptoms in any part of the day were associated with a prior history of exacerbations (all p < 0.05) and nighttime and early-morning symptoms were associated with the frequency of primary care visits in the year before baseline (both p < 0.01). During follow-up, patients with baseline symptoms during any part of the 24-hour day had more exacerbations than patients with no symptoms in each period (all p < 0.05); there was also an association between 24-hour symptoms and the frequency of primary care visits (all p ≤ 0.01). Although there was a significant association between early-morning and daytime symptoms and exacerbations during follow-up (both p < 0.01), significance was not maintained when adjusted for potential confounders. Prior exacerbations were most strongly associated with future risk of exacerbation. The results suggest 24-hour COPD symptoms do not independently predict future exacerbation risk. PMID:26983349

  5. Axial Diffusivity of the Corona Radiata at 24 Hours Post-Stroke: A New Biomarker for Motor and Global Outcome

    PubMed Central

    Moulton, Eric; Amor-Sahli, Mélika; Perlbarg, Vincent; Pires, Christine; Crozier, Sophie; Galanaud, Damien; Valabregue, Romain; Yger, Marion; Baronnet-Chauvet, Flore; Samson, Yves; Dormont, Didier; Rosso, Charlotte

    2015-01-01

    Fractional anisotropy (FA) is an effective marker of motor outcome at the chronic stage of stroke yet proves to be less efficient at early time points. This study aims to determine which diffusion metric in which location is the best marker of long-term stroke outcome after thrombolysis with diffusion tensor imaging (DTI) at 24 hours post-stroke. Twenty-eight thrombolyzed patients underwent DTI at 24 hours post-stroke onset. Ipsilesional and contralesional FA, mean (MD), axial (AD), and radial (RD) diffusivities values were calculated in different Regions-of-Interest (ROIs): (1) the white matter underlying the precentral gyrus (M1), (2) the corona radiata (CoRad), (3) the posterior limb of the internal capsule (PLIC) and (4) the cerebral peduncles (CP). NIHSS scores were acquired at admission, day 1, and day 7; modified Rankin Scores (mRS) at 3 months. Significant decreases were found in FA, MD, and AD of the ipsilesional CoRad and M1. MD and AD were also significantly lower in the PLIC. The ratio of ipsi and contralesional AD of the CoRad (CoRad-rAD) was the strongest diffusion parameter correlated with motor NIHSS scores on day 7 and with the mRS at 3 months. A Receiver-Operator Curve analysis yielded a model for the CoRad-rAD to predict good outcome based on upper limb NIHSS motor scores and mRS with high specificity and sensitivity. FA values were not correlated with clinical outcome. In conclusion, axial diffusivity of the CoRad from clinical DTI at 24 hours post-stroke is the most appropriate diffusion metric for quantifying stroke damage to predict outcome, suggesting the importance of early axonal damage. PMID:26562509

  6. Comparison of Interviewer-Administered and Automated Self-Administered 24-Hour Dietary Recalls in 3 Diverse Integrated Health Systems.

    PubMed

    Thompson, Frances E; Dixit-Joshi, Sujata; Potischman, Nancy; Dodd, Kevin W; Kirkpatrick, Sharon I; Kushi, Lawrence H; Alexander, Gwen L; Coleman, Laura A; Zimmerman, Thea P; Sundaram, Maria E; Clancy, Heather A; Groesbeck, Michelle; Douglass, Deirdre; George, Stephanie M; Schap, TusaRebecca E; Subar, Amy F

    2015-06-15

    Twenty-four-hour dietary recalls provide high-quality intake data but have been prohibitively expensive for large epidemiologic studies. This study's goal was to assess whether the web-based Automated Self-Administered 24-Hour Recall (ASA24) performs similarly enough to the standard interviewer-administered, Automated Multiple-Pass Method (AMPM) 24-hour dietary recall to be considered a viable alternative. In 2010-2011, 1,081 adults from 3 integrated health systems in Detroit, Michigan; Marshfield, Wisconsin; and Kaiser-Permanente Northern California participated in a field trial. A quota design ensured a diverse sample by sex, age, and race/ethnicity. Each participant was asked to complete 2 recalls and was randomly assigned to 1 of 4 protocols differing by type of recall and administration order. For energy, the mean intakes were 2,425 versus 2,374 kcal for men and 1,876 versus 1,906 kcal for women by AMPM and ASA24, respectively. Of 20 nutrients/food groups analyzed and controlling for false discovery rate, 87% were judged equivalent at the 20% bound. ASA24 was preferred over AMPM by 70% of the respondents. Attrition was lower in the ASA24/AMPM study group than in the AMPM/ASA24 group, and it was lower in the ASA24/ASA24 group than in the AMPM/AMPM group. ASA24 offers the potential to collect high-quality dietary intake information at low cost with less attrition. PMID:25964261

  7. Modeling of 24-hour glucose and insulin profiles in patients with type 2 diabetes mellitus treated with biphasic insulin aspart.

    PubMed

    Røge, Rikke M; Klim, Søren; Kristensen, Niels R; Ingwersen, Steen H; Kjellsson, Maria C

    2014-07-01

    Insulin therapy for diabetes patients is designed to mimic the endogenous insulin response of healthy subjects and thereby generate normal blood glucose levels. In order to control the blood glucose in insulin-treated diabetes patients, it is important to be able to predict the effect of exogenous insulin on blood glucose. A pharmacokinetic/pharmacodynamic model for glucose homoeostasis describing the effect of exogenous insulin would facilitate such prediction. Thus the aim of this work was to extend the previously developed integrated glucose-insulin (IGI) model to predict 24-hour glucose profiles for patients with Type 2 diabetes following exogenous insulin administration. Clinical data from two trials were included in the analysis. In both trials, 24-hour meal tolerance tests were used as the experimental setup, where exogenous insulin (biphasic insulin aspart) was administered in relation to meals. The IGI model was successfully extended to include the effect of exogenous insulin. Circadian variations in glucose homeostasis were assessed on relevant parameters, and a significant improvement was achieved by including a circadian rhythm on the endogenous glucose production in the model. The extended model is a useful tool for clinical trial simulation and for elucidating the effect profile of new insulin products. PMID:24446385

  8. QTc interval prolongation in HIV-infected patients: a case–control study by 24-hour Holter ECG recording

    PubMed Central

    2012-01-01

    Background Aim of the study was to assess QTc interval by a 24-hour ECG recording in a group of HIV-infected individuals with a basal prolonged QTc. The risk factors associated with QTc prolongation and the indices of cardiovascular autonomic control were also evaluated. Methods A case–control study was performed using as cases 32 HIV-infected patients with prolonged (>440 msec) QTc interval as assessed by Holter ECG, and as controls 64 HIV-infected subjects with normal QTc interval. Autonomic function was evaluated by heart rate variability analysis during 24-hour recording. Results Duration of HIV disease was significantly longer among cases than among controls (p=0.04). Waist/hip ratio was also higher among cases than among controls (p=0.05). Frequency domain analysis showed the absence of physiologic decrease of low frequency (LF) in the night period in both cases and controls. The LF night in cases showed a statistically significant reduction when compared with controls (p=0.007). Conclusions In our study group, QTc interval prolongation was associated with a longer duration of HIV infection and with a greater waist/hip ratio. HIV patients with QTc interval prolongation and with a longer duration of HIV infection were more likely to have an impairment of parasympathetic and sympathetic cardiac component. PMID:23259665

  9. Designing linear systolic arrays

    SciTech Connect

    Kumar, V.K.P.; Tsai, Y.C. . Dept. of Electrical Engineering)

    1989-12-01

    The authors develop a simple mapping technique to design linear systolic arrays. The basic idea of the technique is to map the computations of a certain class of two-dimensional systolic arrays onto one-dimensional arrays. Using this technique, systolic algorithms are derived for problems such as matrix multiplication and transitive closure on linearly connected arrays of PEs with constant I/O bandwidth. Compared to known designs in the literature, the technique leads to modular systolic arrays with constant hardware in each PE, few control lines, lexicographic data input/output, and improved delay time. The unidirectional flow of control and data in this design assures implementation of the linear array in the known fault models of wafer scale integration.

  10. 24-hour urine protein

    MedlinePlus

    ... of fluid (dehydration) Any type of x-ray exam with dye (contrast material) within 3 days before the urine test Fluid from the vagina that gets into the urine Severe emotional stress Strenuous exercise Urinary tract infection

  11. Urine 24-hour volume

    MedlinePlus

    ... test results: Dehydration Any type of x-ray exam with dye (contrast material) within 3 days before the urine test Fluid from the vagina that gets into the urine Emotional stress Heavy exercise Urinary tract infection

  12. 24-hour care programs.

    PubMed

    Hergenrader, R

    1996-06-01

    Twenty-four-hour care programs, which combine group health programs with workers' compensation and disability benefits, hold considerable potential for cost savings and greater efficiency. This article explains these programs and uses a care history to show the savings they can achieve. PMID:10157798

  13. Urine 24-hour volume

    MedlinePlus

    ... in a day, such as: Creatinine Sodium Potassium Nitrogen Protein This test may also be done if ... disease Potassium urine test Sodium urine test Urea nitrogen urine test Urination - excessive amount Urine output - decreased ...

  14. 24-hour urine protein

    MedlinePlus

    ... a blockage of blood vessels, or other causes Multiple myeloma Healthy people may have higher than normal urine ... Distal Hemolytic anemia Macroglobulinemia of Waldenstrom Microalbuminuria test Multiple myeloma Nephrotic syndrome Proximal Wilson disease Update Date 11/ ...

  15. A 24-hour Approach to the Study of Health Behaviors: Temporal Relationships between Waking Health Behaviors and Sleep

    PubMed Central

    Irish, Leah A.; Kline, Christopher E.; Rothenberger, Scott D.; Krafty, Robert T.; Buysse, Daniel J.; Kravitz, Howard M.; Bromberger, Joyce T.; Zheng, Huiyong; Hall, Martica H.

    2013-01-01

    Background Although sleep is often associated with waking health behaviors (WHB) such as alcohol consumption, caffeine use, smoking, and exercise, the causal direction of these relationships is unclear. Purpose The present study used time-series data to examine the temporal dynamics of WHB and sleep characteristics in participants of the SWAN Sleep Study. Methods 303 women completed daily assessments of WHB and wore wrist actigraphs to measure sleep characteristics for the duration of the study (Mean=29.42 days, SD=6.71). Results Vector autoregressive modeling revealed that weekly patterns of sleep and WHB best predicted subsequent sleep and WHB, suggesting that the associations between WHB and sleep persist beyond their immediate influence. Some WHB predicted some subsequent sleep characteristics, but sleep did not predict subsequent WHB. Conclusions These novel findings provide insight into the temporal dynamics of 24-hour behaviors and encourage consideration of both sleep and WHB in health promotion and behavior change efforts. PMID:24043549

  16. Ultra-Rapid dUT1 Measurements on Japan-Fennoscandian Baselines - Application to 24-hour Sessions

    NASA Technical Reports Server (NTRS)

    Matsuzaka, Shigeru; Kurihara, Shinobu; Sekido, Mamoru; Hobiger, Thomas; Haas, Rudiger; Ritakari, Jouko; Wagner, Jan

    2010-01-01

    GSI, NICT, OSO, and MRO have been engaged in Ultra-rapid dUT1 experiments since 2007 aiming at the technological possibility of real-time dUT1 results using the e-VLBI technique. We have already successfully determined dUT1 in less than four minutes after the end of an experimental Intensive session in 2008, and at present we routinely get the results within 30 minutes for regular Intensives. In 2009 we applied the technique to 24-hour sessions and continuously obtained dUT1 values by processing and analyzing Tsukuba Onsala data in near real-time. It showed a detailed behavior of UT1 variations, which could be very valuable for scientific study as well as for precise prediction of UT1-UTC.

  17. Tolvaptan Prolongs Blockage of the Vasopressin Type II Receptor Over 24 Hours in Responders With Stage D Heart Failure.

    PubMed

    Imamura, Teruhiko; Kinugawa, Koichiro; Komuro, Issei

    2016-01-01

    The urine aquaporin-2 (U-AQP2) level relative to the plasma arginine vasopressin (P-AVP) level is a novel predictor of the responsiveness to the vasopressin type 2 receptor (V2R) antagonist tolvaptan (TLV). However, little has been reported about the concentration-time profile of U-AQP2 after TLV treatment. We evaluated 24 patients with decompensated stage D heart failure (HF) who had received 3.75 mg/day of TLV on a de novo basis for > 7 days to treat congestion refractory to conventional diuretics. Seventeen patients were TLV-responders, whose 24-hour urine volume (UV) increased after TLV initiation; the other 7 patients were TLV-non-responders. The U-AQP2 of the TLV-responders, corrected for the urine creatinine concentration, decreased significantly at 4 hours after TLV administration without returning to the day-1 morning level on the morning of day-7. The TLV-non-responder U-AQP2 levels remained low even before the TLV treatment. On the morning of day-7, the TLV-responder U-AQP2/P-AVP ratio was comparable to that of the TLV-non-responders. Among 18 patients (11 responders and 7 non-responders), the day-7 TLV trough concentration was 64 ± 62 ng/mL and was negatively correlated with the estimated glomerular filtration rate (eGFR). TLV has antagonistic effects on the V2R over 24 hours in TLV-responders with advanced heart failure and chronic kidney disease, probably due to persistently elevated blood TLV concentration. The unresponsiveness to TLV in the TLV-non-responders is not attributable to malabsorption. PMID:26742881

  18. Prognostic Value of the 24-Hour Neurological Examination in Anterior Circulation Ischemic Stroke: A post hoc Analysis of Two Randomized Controlled Stroke Trials

    PubMed Central

    Rangaraju, Srikant; Frankel, Michael; Jovin, Tudor G.

    2016-01-01

    Background Early prognostication of long-term outcomes following ischemic stroke can facilitate medical decision-making. We hypothesized that the 24-hour National Institute of Health Stroke Scale (NIHSS) predicts 3-month clinical outcomes in anterior circulation stroke. Methods Secondary analyses of the Interventional Management of Stroke 3 (IMS3) and intravenous tissue plasminogen activator (IV tPA) for acute ischemic stroke [National Institute of Neurological Diseases and Stroke (NINDS) IV tPA] trials were performed. In participants with documented 24-hour NIHSS and 3-month Modified Rankin Scale (mRS), the predictive power of the 24-hour NIHSS and 24-hour NIHSS improvement for 3-month outcomes [mRS 0-2 and Barthel Index (BI) ≥95] was assessed. Percentages of good outcome (mRS 0-2 or BI ≥95) at 3, 6, and 12 months and mean quality of life (EQ5D™) index at 3 months across 24-hour NIHSS quartiles were compared. Results The majority of the study participants were included (IMS3 n = 587/656, NINDS IV tPA n = 619/624). The 24-hour NIHSS was correlated with 3-month mRS (R = 0.73) with excellent predictive power for mRS 0-2 [area under the curve (AUC) = 0.91] and BI ≥95 (AUC = 0.9) in both cohorts. A model with the 24-hour NIHSS alone correctly classified 82-84% of patients in both cohorts. The percentages of good outcomes at 3-12 months across 24-hour NIHSS quartiles were similar in both cohorts. mRS 0-2 was achieved by 75.6-77.7% of patients with 24-hour NIHSS ≤11 but by only 1.4-3.6% with 24-hour NIHSS ≥20. The EQ5D index at 3 months varied among NIHSS 0-4 (mean 0.86 ± 0.16), 5-11 (0.77 ± 0.18), and 12-19 (0.59 ± 0.26) quartiles. Conclusions The 24-hour NIHSS strongly predicts long-term stroke outcomes and is associated with quality of life. Its easy availability, reliability, and validity support its use as an early prognostic marker and surrogate of clinical outcome in ischemic stroke. PMID:27051408

  19. The prevalence of exercise-associated hyponatremia in 24-hour ultra-mountain bikers, 24-hour ultra-runners and multi-stage ultra-mountain bikers in the Czech Republic

    PubMed Central

    2014-01-01

    Background To assess the prevalence of exercise-associated hyponatremia (EAH) in two 24-hour mountain bike (MTB) (R1,R2), one 24-hour running (R3) and one multi-stage MTB (R4) races held in the Czech Republic in a cluster of four cross-sectional studies. Methods In 27 ultra-mountain bikers (ultra-MTBers), 12 ultra-runners, and 14 multi-stage MTBers, fluid intake, changes (Δ) in body mass, hematocrit, plasma volume, plasma [Na+], plasma [K+], plasma osmolality, urine [Na+], urine [K+], urine specific gravity, urine osmolality, K+/Na+ ratio in urine, transtubular potassium gradient and glomerular filtration rate were measured and calculated. The use of non-steroidal anti-inflammatory drugs and symptoms of EAH were recorded using post-race questionnaires. Results Of the 53 finishers, three (5.7%) developed post-race EAH, thereof one (3.7%) ultra-MTBer, one (8.3%) ultra-runner and one (7.1%) multi-stage MTBer. Plasma [Na+] decreased significantly (p < 0.001) only in R4. Urine osmolality (R1, R3, R4 p < 0.001; R2 p < 0.05) and glomerular filtration rate (p < 0.001) increased, and body mass decreased in all races (p < 0.05). Δ body mass was inversely related to the number of kilometers achieved (p < 0.001) in R2 where better ultra-MTBers tended to lose more weight. Δ body mass (p < 0.001) and %Δ body mass (p = 0.05) were positively related to lower post-race plasma [Na+] in R3 that was associated with increased loss in body mass. Fluid intake was positively related to race performance in R1 and R2 (R1: p = 0.04; R2: p = 0.01) where ultra-MTBers in R1 and R2 who drank more finished ahead of those who drank less. Post-race plasma [Na+] was negatively associated with race performance in ultra-MTBers in R2 (p < 0.05), similarly ultra-runners in R3 (p < 0.05) where finishers with more kilometres had lower post-race plasma [Na+]. Conclusions The prevalence of EAH in the Czech Republic was no higher compared to existing reports on ultra-endurance athletes in other countries

  20. Synchronizing large systolic arrays

    SciTech Connect

    Fisher, A.L.; Kung, H.T.

    1982-04-01

    Parallel computing structures consist of many processors operating simultaneously. If a concurrent structure is regular, as in the case of systolic array, it may be convenient to think of all processors as operating in lock step. Totally synchronized systems controlled by central clocks are difficult to implement because of the inevitable problem of clock skews and delays. An alternate means of enforcing necessary synchronization is the use of self-timed, asynchronous schemes, at the cost of increased design complexity and hardware cost. Realizing that different circumstances call for different synchronization methods, this paper provides a spectrum of synchronization models; based on the assumptions made for each model, theoretical lower bounds on clock skew are derived, and appropriate or best-possible synchronization schemes for systolic arrays are proposed. This paper represents a first step towards a systematic study of synchronization problems for large systolic arrays.

  1. Systolic and semisystolic design

    SciTech Connect

    Leiserson, C.E.

    1983-01-01

    Architectural transformation techniques which can be used to help produce efficient systolic and semisystolic architectures for signal processing, image processing, numerical computation and raster graphics are identified. The transformations include: retiming, slowdown, broadcast and census elimination, coalescing, interlacing, code motion, resetting, register elimination and parallel/serial compromises. All the transformations are at the architectural or algorithmic level, as distinct from the electrical circuit level, and provide high-level tools for a designer. In addition, they provide a step toward automatic compilation of systolic and semisystolic systems. 12 references.

  2. Mean 24-hours sympathetic nervous system activity decreases during head-down tilted bed rest but not during microgravity

    NASA Astrophysics Data System (ADS)

    Christensen, Nj; Heer, M.; Ivanova, K.; Norsk, P.

    Sympathetic nervous system activity is closely related to gravitational stress in ground based experiments. Thus a high activity is present in the standing-up position and a very low activity is observed during acute head-out water immersion. Adjustments in sympathetic activity are necessary to maintain a constant blood pressure during variations in venous return. Head-down tilted bed rest is applied as a model to simulate changes observed during microgravity. The aim of the present study was to test the hypothesis that mean 24-hours sympathetic activity was low and similar during space flight and in ground based observation obtained during long-term head-down tilted bed rest. Forearm venous plasma noradrenaline was measured by a radioenzymatic technique as an index of muscle sympathetic activity and thrombocyte noradrenaline and adrenaline were measured as indices of mean 24-hours sympathoadrenal activity. Previous results have indicated that thrombocyte noradrenaline level has a half-time of 2 days. Thus to reflect sympathetic activity during a specific experiment the study period must last for at least 6 days and a sample must be obtained within 12 hours after the experiment has ended. Ten normal healthy subjects were studied before and during a 14 days head-down tilted bed rest as well as during an ambulatory study period of a similar length. The whole experiment was repeated while the subjects were on a low calorie diet. Thrombocyte noradrenaline levels were studied in 4 cosmonauts before and within 12 hours after landing after more than 7 days in flight. Thrombocyte noradrenaline decreased markedly during the head-down tilted bed rest (p<0.001), whereas there were no significant changes in the ambulatory study. Plasma noradrenaline decreased in the adaptation period but not during the intervention. During microgravity thrombocyte noradrenaline increased in four cosmonauts and the percentage changes were significantly different in cosmonauts and in subjects

  3. Dietary quality varies according to data collection instrument: a comparison between a food frequency questionnaire and 24-hour recall.

    PubMed

    Rodrigues, Paulo Rogério Melo; de Souza, Rita Adriana Gomes; De Cnop, Mara Lima; Monteiro, Luana Silva; Coura, Camila Pinheiro; Brito, Alessandra Page; Pereira, Rosangela Alves

    2016-02-01

    The objective of this study was to assess the agreement between the Brazilian Healthy Eating Index - Revised (BHEI-R), estimated by a food frequency questionnaire (FFQ) and multiple 24-hour recalls (24h-R). The Wilcoxon paired test, partial correlations (PC), intraclass correlation coefficient (ICC), and Bland-Altman method were used. The total BHEI-R scores and its components ("total fruits", "whole fruits", "total vegetables", "integral cereals", "saturated fat", "sodium", and "energy intake derived from solid fat, added sugar, and alcoholic beverages") were statistically different, with the ICC and PC indicating poor concordance and correlation. The mean concordance estimated for the total BHEI-R and its components varied from 68% for "integral cereals" to 147% for "whole fruits". The suitable concordance limits were violated for most of the components of the BHEI-R. Poor concordance was observed between the BHEI-R estimated by the FFQ and by multiple 24h-R, which indicated a strong reliability of the BHEI-R on the instrument used to collect information on food consumption. PMID:26910251

  4. Relative prognostic value of rest thallium-201 imaging, radionuclide ventriculography and 24 hour ambulatory electrocardiographic monitoring after acute myocardial infarction

    SciTech Connect

    Hakki, A.H.; Nestico, P.F.; Heo, J.; Unwala, A.A.; Iskandrian, A.S.

    1987-07-01

    Rest thallium-201 scintigraphy, radionuclide ventriculography and 24 hour Holter monitoring are acceptable methods to assess myocardial necrosis, performance and electrical instability. This study examined the relative value of the three tests, when obtained a mean of 7 days after acute myocardial infarction, in predicting 1 year mortality in 93 patients. Planar thallium-201 images were obtained in three projections and were scored on a scale of 0 to 4 in 15 segments (normal score = 60). Patients were classified as having high risk test results as follows: thallium score less than or equal to 45 (33 patients), left ventricular ejection fraction less than or equal to 40% (51 patients) and complex ventricular arrhythmias on Holter monitoring (36 patients). During the follow-up of 6.4 +/- 3.4 months (mean +/- SD), 15 patients died of cardiac causes. All three tests were important predictors of survival by univariate Cox survival analysis; the thallium score, however, was the only important predictor by multivariate analysis. The predictive power of the thallium score was comparable with that of combined ejection fraction and Holter monitoring (chi-square = 21 versus chi-square = 22). Thus, rest thallium-201 imaging performed before hospital discharge provides important prognostic information in survivors of acute myocardial infarction which is comparable with that provided by left ventricular ejection fraction and Holter monitoring. Patients with a lower thallium score (large perfusion defects) are at high risk of cardiac death during the first year after infarction.

  5. Extracorporeal membrane oxygenation improves survival in a novel 24-hour pig model of severe acute respiratory distress syndrome.

    PubMed

    Araos, Joaquín; Alegría, Leyla; García, Patricio; Damiani, Felipe; Tapia, Pablo; Soto, Dagoberto; Salomon, Tatiana; Rodriguez, Felipe; Amthauer, Macarena; Erranz, Benjamín; Castro, Gabriel; Carreño, Pamela; Medina, Tania; Retamal, Jaime; Cruces, Pablo; Bugedo, Guillermo; Bruhn, Alejandro

    2016-01-01

    Extracorporeal membrane oxygenation (ECMO) is increasingly being used to treat severe acute respiratory distress syndrome (ARDS). However, there is limited clinical evidence about how to optimize the technique. Experimental research can provide an alternative to fill the actual knowledge gap. The purpose of the present study was to develop and validate an animal model of acute lung injury (ALI) which resembled severe ARDS, and which could be successfully supported with ECMO. Eighteen pigs were randomly allocated into three groups: sham, ALI, and ALI + ECMO. ALI was induced by a double-hit consisting in repeated saline lavage followed by a 2-hour period of injurious ventilation. All animals were followed up to 24 hours while being ventilated with conventional ventilation (tidal volume 10 ml/kg). The lung injury model resulted in severe hypoxemia, increased airway pressures, pulmonary hypertension, and altered alveolar membrane barrier function, as indicated by an increased protein concentration in bronchoalveolar fluid, and increased wet/dry lung weight ratio. Histologic examination revealed severe diffuse alveolar damage, characteristic of ARDS. Veno-venous ECMO was started at the end of lung injury induction with a flow > 60 ml/kg/min resulting in rapid reversal of hypoxemia and pulmonary hypertension. Mortality was 0, 66.6 and 16.6% in the SHAM, ALI and ALI + ECMO groups, respectively (p < 0.05). This is a novel clinically relevant animal model that can be used to optimize the approach to ECMO and foster translational research in extracorporeal lung support. PMID:27398166

  6. Extracorporeal membrane oxygenation improves survival in a novel 24-hour pig model of severe acute respiratory distress syndrome

    PubMed Central

    Araos, Joaquín; Alegría, Leyla; García, Patricio; Damiani, Felipe; Tapia, Pablo; Soto, Dagoberto; Salomon, Tatiana; Rodriguez, Felipe; Amthauer, Macarena; Erranz, Benjamín; Castro, Gabriel; Carreño, Pamela; Medina, Tania; Retamal, Jaime; Cruces, Pablo; Bugedo, Guillermo; Bruhn, Alejandro

    2016-01-01

    Extracorporeal membrane oxygenation (ECMO) is increasingly being used to treat severe acute respiratory distress syndrome (ARDS). However, there is limited clinical evidence about how to optimize the technique. Experimental research can provide an alternative to fill the actual knowledge gap. The purpose of the present study was to develop and validate an animal model of acute lung injury (ALI) which resembled severe ARDS, and which could be successfully supported with ECMO. Eighteen pigs were randomly allocated into three groups: sham, ALI, and ALI + ECMO. ALI was induced by a double-hit consisting in repeated saline lavage followed by a 2-hour period of injurious ventilation. All animals were followed up to 24 hours while being ventilated with conventional ventilation (tidal volume 10 ml/kg). The lung injury model resulted in severe hypoxemia, increased airway pressures, pulmonary hypertension, and altered alveolar membrane barrier function, as indicated by an increased protein concentration in bronchoalveolar fluid, and increased wet/dry lung weight ratio. Histologic examination revealed severe diffuse alveolar damage, characteristic of ARDS. Veno-venous ECMO was started at the end of lung injury induction with a flow > 60 ml/kg/min resulting in rapid reversal of hypoxemia and pulmonary hypertension. Mortality was 0, 66.6 and 16.6% in the SHAM, ALI and ALI + ECMO groups, respectively (p < 0.05). This is a novel clinically relevant animal model that can be used to optimize the approach to ECMO and foster translational research in extracorporeal lung support. PMID:27398166

  7. An Analysis of 24-Hour Ambulatory Blood Pressure Monitoring Data using Orthonormal Polynomials in the Linear Mixed Model

    PubMed Central

    Edwards, Lloyd J.; Simpson, Sean L.

    2014-01-01

    Background The use of 24-hour ambulatory blood pressure monitoring (ABPM) in clinical practice and observational epidemiological studies has grown considerably in the past 25 years. ABPM is a very effective technique for assessing biological, environmental, and drug effects on blood pressure. Objectives In order to enhance the effectiveness of ABPM for clinical and observational research studies via analytical and graphical results, developing alternative data analysis approaches using modern statistical techniques are important. Methods The linear mixed model for the analysis of longitudinal data is particularly well-suited for the estimation of, inference about, and interpretation of both population (mean) and subject-specific trajectories for ABPM data. We propose using a linear mixed model with orthonormal polynomials across time in both the fixed and random effects to analyze ABPM data. Results We demonstrate the proposed analysis technique using data from the Dietary Approaches to Stop Hypertension (DASH) study, a multicenter, randomized, parallel arm feeding study that tested the effects of dietary patterns on blood pressure. Conclusions The linear mixed model is relatively easy to implement (given the complexity of the technique) using available software, allows for straight-forward testing of multiple hypotheses, and the results can be presented to research clinicians using both graphical and tabular displays. Using orthonormal polynomials provides the ability to model the nonlinear trajectories of each subject with the same complexity as the mean model (fixed effects). PMID:24667908

  8. Dipper and non-dipper blood pressure 24-hour patterns: circadian rhythm-dependent physiologic and pathophysiologic mechanisms.

    PubMed

    Fabbian, Fabio; Smolensky, Michael H; Tiseo, Ruana; Pala, Marco; Manfredini, Roberto; Portaluppi, Francesco

    2013-03-01

    Neuroendocrine mechanisms are major determinants of the normal 24-h blood pressure (BP) pattern. At the central level, integration of the major driving factors of this temporal variability is mediated by circadian rhythms of monoaminergic systems in conjunction with those of the hypothalamic-pituitary-adrenal, hypothalamic-pituitary-thyroid, opioid, renin-angiotensin-aldosterone, plus endothelial systems and specific vasoactive peptides. Humoral secretions are typically episodic, coupled either to sleep and/or the circadian endogenous (suprachiasmatic nucleus) central pacemaker clock, but exhibiting also weekly, monthly, seasonal, and annual periodicities. Sleep induction and arousal are influenced also by many hormones and chemical substances that exhibit 24-h variation, e.g., arginine vasopressin, vasoactive intestinal peptide, melatonin, somatotropin, insulin, steroids, serotonin, corticotropin-releasing factor, adrenocorticotropic hormone, thyrotropin-releasing hormone, endogenous opioids, and prostaglandin E2, all with established effects on the cardiovascular system. As a consequence, physical, mental, and pathologic stimuli that activate or inhibit neuroendocrine effectors of biological rhythmicity may also interfere with, or modify, the temporal BP structure. Moreover, immediate adjustment to exogenous components/environment demands by BP rhythms is modulated by the circadian-time-dependent responsiveness of biological oscillators and their neuroendocrine effectors. This knowledge contributes to a better understanding of the pathophysiology of abnormalities of the 24-h BP pattern and level and their correction through circadian rhythm-based chronotherapeutic strategies. PMID:23002916

  9. Under-reporting of Energy Intake from 24-hour Dietary Recalls in the Korean National Health and Nutrition Examination Survey

    PubMed Central

    Kye, Seunghee; Kwon, Sung-Ok; Lee, Soon-Young; Lee, Jiyoon; Kim, Bok Hee; Suh, Hee-Jae; Moon, Hyun-Kyung

    2014-01-01

    Objectives Chronic degenerative diseases are closely related to daily eating habits, nutritional status, and, in particular, energy intake. In clarifying these relationships it is very important for dietary surveys to report accurate information about energy intake. This study attempted to identify the prevalence of the under-reporting of energy intake and its related characteristics based on the Korean National Health and Nutrition Examination Survey conducted in the years 2007–2009. Methods The present study analyzed dietary intake data from 15,133 adults aged ≥19 years using 24-hour dietary recalls. Basal metabolic rates were calculated from the age- and gender-specific equations of Schofield and under-reporting was defined as an energy intake <0.9, represented by the ratio of energy intake to estimated basal metabolic rate. Results Under-reporters (URs) accounted for 14.4% of men and 23.0% of women and the under-reporting rate was higher in the age group 30–49 years for both men and women. The results from an analysis of the age-specific socioeconomic characteristics of participants classified as URs showed that under-reporting was high in women living alone and in women with only elementary school education or no education. The results from an analysis of the health-specific characteristics of URs showed that a large proportion of URs had poor self-rated health or were obese, or both, compared with non-URs. The proportion of participants who consumed less than the estimated average requirements for nutrients was significantly higher in URs compared with non-URs. Conclusion The under-reporting of energy intake was associated with age, gender, education level, income level, household status (single-person or multi-person), self-rated health, physical activity, and obesity. PMID:24955317

  10. Variants in the LEPR gene are nominally associated with higher BMI and lower 24 hour energy expenditure in Pima Indians

    PubMed Central

    Traurig, Michael; Perez, Jessica; Ma, Lijun; Bian, Li; Kobes, Sayuko; Hanson, Robert L.; Knowler, William C.; Krakoff, Jonathan; Bogardus, Clifton; Baier, Leslie J.

    2012-01-01

    Genome-wide association studies (GWASs) have been used to search for susceptibility genes for type 2 diabetes and obesity in the Pima Indians, a population with high a prevalence of both diseases. In these studies, a variant (rs2025804) in the LEPR gene was nominally associated with BMI in 1082 subjects (P=0.03 adjusted for age, sex, birth year, and family membership). Therefore the LEPR and leptin overlapping transcript (LEPROT) genes were selected for further sequencing and genotyping in larger population-based samples for association analyses with obesity-related phenotypes. Selected variants (n=80) spanning these genes were genotyped in a sample of full-heritage Pima Indians (n=2842) and several common variants including rs2025804 were nominally associated with BMI (P=0.05-0.003 adjusted for age, sex, birth year, and family membership). Four common tag variants associated with BMI in the full-heritage Pima Indian sample were genotyped in a second sample of mixed-heritage Native Americans (n=2969) and 3 of the variants showed nominal replication (P=0.03-0.006 adjusted as above and additionally for Indian heritage). Combining both samples provided the strongest evidence for association (adjusted P=0.0003-0.0001). A subset of these individuals (n=403) had been metabolically characterized for predictors of obesity and the BMI risk alleles for the variants tagged by rs2025804 were also associated with lower 24 hour energy expenditure as assessed in a human respiratory chamber (P=0.0007 adjusted for age, sex, fat mass, fat free mass, activity, and family membership). We conclude that common non-coding variation in the LEPR gene is associated with higher BMI and lower energy expenditure in Native Americans. PMID:22810975

  11. 24-hour human urine and serum profiles of bisphenol A: Evidence against sublingual absorption following ingestion in soup.

    PubMed

    Teeguarden, Justin G; Twaddle, Nathan C; Churchwell, Mona I; Yang, Xiaoxia; Fisher, Jeffrey W; Seryak, Liesel M; Doerge, Daniel R

    2015-10-15

    Extensive first-pass metabolism of ingested bisphenol A (BPA) in the gastro-intestinal tract and liver restricts blood concentrations of bioactive BPA to <1% of total BPA in humans and non-human primates. Absorption of ingested BPA through non-metabolizing tissues of the oral cavity, recently demonstrated in dogs, could lead to the higher serum BPA concentrations reported in some human biomonitoring studies. We hypothesized that the extensive interaction with the oral mucosa by a liquid matrix, like soup, relative to solid food or capsules, might enhance absorption through non-metabolizing oral cavity tissues in humans, producing higher bioavailability and higher serum BPA concentrations. Concurrent serum and urine concentrations of d6-BPA, and its glucuronide and sulfate conjugates, were measured over a 24hour period in 10 adult male volunteers following ingestion of 30μg d6-BPA/kg body weight in soup. Absorption of d6-BPA was rapid (t1/2=0.45h) and elimination of the administered dose was complete 24h post-ingestion, evidence against any tissue depot for BPA. The maximum serum d6-BPA concentration was 0.43nM at 1.6h after administration and represented <0.3% of total d6-BPA. Pharmacokinetic parameters, pharmacokinetic model simulations, and the significantly faster appearance half-life of d6-BPA-glucuronide compared to d6-BPA (0.29h vs 0.45h) were evidence against meaningful absorption of BPA in humans through any non-metabolizing tissue (<1%). This study confirms that typical exposure to BPA in food produces picomolar to subpicomolar serum BPA concentrations in humans, not nM concentrations reported in some biomonitoring studies. PMID:25620055

  12. Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep.

    PubMed

    Tremblay, Mark S; Carson, Valerie; Chaput, Jean-Philippe; Connor Gorber, Sarah; Dinh, Thy; Duggan, Mary; Faulkner, Guy; Gray, Casey E; Gruber, Reut; Janson, Katherine; Janssen, Ian; Katzmarzyk, Peter T; Kho, Michelle E; Latimer-Cheung, Amy E; LeBlanc, Claire; Okely, Anthony D; Olds, Timothy; Pate, Russell R; Phillips, Andrea; Poitras, Veronica J; Rodenburg, Sophie; Sampson, Margaret; Saunders, Travis J; Stone, James A; Stratton, Gareth; Weiss, Shelly K; Zehr, Lori

    2016-06-01

    Leaders from the Canadian Society for Exercise Physiology convened representatives of national organizations, content experts, methodologists, stakeholders, and end-users who followed rigorous and transparent guideline development procedures to create the Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep. These novel guidelines for children and youth aged 5-17 years respect the natural and intuitive integration of movement behaviours across the whole day (24-h period). The development process was guided by the Appraisal of Guidelines for Research Evaluation (AGREE) II instrument and systematic reviews of evidence informing the guidelines were assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Four systematic reviews (physical activity, sedentary behaviour, sleep, integrated behaviours) examining the relationships between and among movement behaviours and several health indicators were completed and interpreted by expert consensus. Complementary compositional analyses were performed using Canadian Health Measures Survey data to examine the relationships between movement behaviours and health indicators. A stakeholder survey was employed (n = 590) and 28 focus groups/stakeholder interviews (n = 104) were completed to gather feedback on draft guidelines. Following an introductory preamble, the guidelines provide evidence-informed recommendations for a healthy day (24 h), comprising a combination of sleep, sedentary behaviours, light-, moderate-, and vigorous-intensity physical activity. Proactive dissemination, promotion, implementation, and evaluation plans have been prepared in an effort to optimize uptake and activation of the new guidelines. Future research should consider the integrated relationships among movement behaviours, and similar integrated guidelines for other age groups should be developed. PMID:27306437

  13. Relationships Between Blood Pressure and 24-Hour Urinary Excretion of Sodium and Potassium by Body Mass Index Status in Chinese Adults.

    PubMed

    Yan, Liuxia; Bi, Zhenqiang; Tang, Junli; Wang, Linhong; Yang, Quanhe; Guo, Xiaolei; Cogswell, Mary E; Zhang, Xiaofei; Hong, Yuling; Engelgau, Michael; Zhang, Jiyu; Elliott, Paul; Angell, Sonia Y; Ma, Jixiang

    2015-12-01

    This study examined the impact of overweight/obesity on sodium, potassium, and blood pressure associations using the Shandong-Ministry of Health Action on Salt Reduction and Hypertension (SMASH) project baseline survey data. Twenty-four-hour urine samples were collected in 1948 Chinese adults aged 18 to 69 years. The observed associations of sodium, potassium, sodium-potassium ratio, and systolic blood pressure (SBP) were stronger in the overweight/obese population than among those of normal weight. Among overweight/obese respondents, each additional standard deviation (SD) higher of urinary sodium excretion (SD=85 mmol) and potassium excretion (SD=19 mmol) was associated with a 1.31 mm Hg (95% confidence interval, 0.37-2.26) and -1.43 mm Hg (95% confidence interval, -2.23 to -0.63) difference in SBP, and each higher unit in sodium-potassium ratio was associated with a 0.54 mm Hg (95% confidence interval, 0.34-0.75) increase in SBP. The association between sodium, potassium, sodium-potassium ratio, and prevalence of hypertension among overweight/obese patients was similar to that of SBP. Our study indicated that the relationships between BP and both urinary sodium and potassium might be modified by BMI status in Chinese adults. PMID:26332433

  14. Jack Healy Remembers - Anecdotal Evidence for the Origin of the Approximate 24-hour Urine Sampling Protocol Used for Worker Bioassay Monitoring

    SciTech Connect

    Carbaugh, Eugene H.

    2008-10-01

    The origin of the approximate 24-hour urine sampling protocol used at Hanford for routine bioassay is attributed to an informal study done in the mid-1940s. While the actual data were never published and have been lost, anecdotal recollections by staff involved in the initial bioassay program design and administration suggest that the sampling protocol had a solid scientific basis. Numerous alternate methods for normalizing partial day samples to represent a total 24-hour collection have since been proposed and used, but no one method is obviously preferred.

  15. Efficacy of combination therapy for systolic blood pressure in patients with severe systolic hypertension: the Systolic Evaluation of Lotrel Efficacy and Comparative Therapies (SELECT) study.

    PubMed

    Neutel, Joel M; Smith, David H G; Weber, Michael A; Schofield, Lesley; Purkayastha, Das; Gatlin, Marjorie

    2005-11-01

    Systolic hypertension is predominant among patients over 50 years of age, is a more important cardiovascular risk factor than diastolic blood pressure, and is more difficult to control than diastolic blood pressure. Consequently, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) recommends combination therapy as first-line treatment for patients with stage 2 hypertension. In the Systolic Evaluation of Lotrel Efficacy and Comparative Therapies (SELECT) study, 24-hour ambulatory blood pressure monitoring was used to identify patients with systolic hypertension and to determine the impact of 8 weeks of treatment with either amlodipine besylate/benazepril HCl 5/20 mg combination therapy (n=149), amlodipine besylate 5 mg (n=146), or benazepril HCl 20 mg (n=148). Combination therapy was significantly more effective in reducing systolic blood pressure and pulse pressure than either monotherapy (p<0.0001). Significantly greater percentages of patients in the combination group compared with either monotherapy achieved blood pressure control (p<0.0001). Adverse events were low in all three treatment arms, with less peripheral edema in the combination group than in the amlodipine-treated group. The combination of amlodipine besylate/benazepril HCl given to patients with stage 2 systolic hypertension resulted in significantly greater reductions in blood pressure and pulse pressure than those seen with monotherapy and was at least as well tolerated as the separate components. This data supports the recommendation of the JNC 7 for the use of combination therapy in patients with stage 2 hypertension. PMID:16278521

  16. Design of robust systolic algorithms

    SciTech Connect

    Varman, P.J.; Fussell, D.S.

    1983-01-01

    A primary reason for the susceptibility of systolic algorithms to faults is their strong dependence on the interconnection between the processors in a systolic array. A technique to transform any linear systolic algorithm into an equivalent pipelined algorithm that executes on arbitrary trees is presented. 5 references.

  17. Perfusion-CT - Can We Predict Acute Pancreatitis Outcome within the First 24 Hours from the Onset of Symptoms?

    PubMed Central

    Pieńkowska, Joanna; Gwoździewicz, Katarzyna; Skrobisz-Balandowska, Katarzyna; Marek, Iwona; Kostro, Justyna; Szurowska, Edyta; Studniarek, Michał

    2016-01-01

    Purpose Severe acute pancreatitis (AP) is still a significant clinical problem which is associated with a highly mortality. The aim of this study was the evaluation of prognostic value of CT regional perfusion measurement performed on the first day of onset of symptoms of AP, in assessing the risk of developing severe form of acute pancreatitis. Material and Methods 79 patients with clinical symptoms and biochemical criteria indicative of acute pancreatitis (acute upper abdominal pain, elevated levels of serum amylase and lipase) underwent perfusion CT within 24 hours after onset of symptoms. The follow-up examinations were performed after 4–6 days to detect progression of the disease. Perfusion parameters were compared in 41 people who developed severe form of AP (pancreatic and/or peripancreatic tissue necrosis) with parameters in 38 consecutive patients in whom course of AP was mild. Blood flow, blood volume, mean transit time and permeability surface area product were calculated in the three anatomic pancreatic subdivisions (head, body and tail). At the same time the patient's clinical status was assessed by APACHE II score and laboratory parameters such as CRP, serum lipase and amylase, AST, ALT, GGT, ALP and bilirubin were compared. Results Statistical differences in the perfusion parameters between the group of patients with mild and severe AP were shown. Blood flow, blood volume and mean transit time were significantly lower and permeability surface area product was significantly higher in patients who develop severe acute pancreatitis and presence of pancreatic and/or peripancreatic necrosis due to pancreatic ischemia. There were no statistically significant differences between the two groups in terms of evaluated on admission severity of pancreatitis assessed using APACHE II score and laboratory tests. Conclusions CT perfusion is a very useful indicator for prediction and selection patients in early stages of acute pancreatitis who are at risk of

  18. Systolic processor for signal processing

    SciTech Connect

    Frank, G.A.; Greenawalt, E.M.; Kulkarni, A.V.

    1982-01-01

    A systolic array is a natural architecture for a high-performance signal processor, in part because of the extensive use of inner-product operations in signal processing. The modularity and simple interconnection of systolic arrays promise to simplify the development of cost-effective, high-performance, special-purpose processors. ESL incorporated has built a proof of concept model of a systolic processor. It is flexible enough to permit experimentation with a variety of algorithms and applications. ESL is exploring the application of systolic processors to image- and signal-processing problems. This paper describes this experimental system and some of its applications to signal processing. ESL is also pursuing new types of systolic architectures, including the VLSI implementation of systolic cells for solving systems of linear equations. These new systolic architectures allow the real-time design of adaptive filters. 14 references.

  19. Characterization of pulmonary protein profiles in response to zinc oxide nanoparticles in mice: a 24-hour and 28-day follow-up study

    PubMed Central

    Pan, Chih-Hong; Chuang, Kai-Jen; Chen, Jen-Kun; Hsiao, Ta-Chih; Lai, Ching-Huang; Jones, Tim P; BéruBé, Kelly A; Hong, Gui-Bing; Ho, Kin-Fai; Chuang, Hsiao-Chi

    2015-01-01

    Although zinc oxide nanoparticles (ZnONPs) are recognized to cause systemic disorders, little is known about the mechanisms that underlie the time-dependent differences that occur after exposure. The objective of this study was to investigate the mechanistic differences at 24 hours and 28 days after the exposure of BALB/c mice to ZnONPs via intratracheal instillation. An isobaric tag for the relative and absolute quantitation coupled with liquid chromatography/tandem mass spectrometry was used to identify the differential protein expression, biological processes, molecular functions, and pathways. A total of 18 and 14 proteins displayed significant changes in the lung tissues at 24 hours and 28 days after exposure, respectively, with the most striking changes being observed for S100-A9 protein. Metabolic processes and catalytic activity were the main biological processes and molecular functions, respectively, in the responses at the 24-hour and 28-day follow-up times. The glycolysis/gluconeogenesis pathway was continuously downregulated from 24 hours to 28 days, whereas detoxification pathways were activated at the 28-day time-point after exposure. A comprehensive understanding of the potential time-dependent effects of exposure to ZnONPs was provided, which highlights the metabolic mechanisms that may be important in the responses to ZnONP. PMID:26251593

  20. VALIDATION OF THREE FOOD FREQUENCY QUESTIONNAIRES AND 24-HOUR RECALLS WITH SERUM CAROTENOID LEVELS IN A SAMPLE OF AFRICAN-AMERICAN ADULTS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The validity of self-reported fruit and vegetable intake in minority populations has not been adequately established. In this study, the authors examined the association of three food frequency questionnaires (FFQs) and 24-hour dietary recalls with serum carotenoid levels. Approximately 1,000 Africa...

  1. Validation of the automated self-administered 24-hour dietary recall for children (ASA24-Kids) among 9- to 11-year-old youth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our purpose was to validate ASA24-Kids-2012, a self-administered web-based 24-hour dietary recall (24hDR) among 9- to 11-year-old children. Sixty-nine children in two sites participated in the study. In one site, trained staff observed and recorded types and portions of foods and drinks consumed by ...

  2. Identifying nutrients that are under-reported by an automated 24-hour dietary recall method in overweight and obese women after weight loss

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Underreporting of energy intake by 15-50% is a common problem in dietary assessment. Evidence suggests overweight/obese respondents are more likely to under-report than normal weight. This study compared Automated Self-Administered 24-hour recall (ASA24)-reported dietary intake to true intake in ove...

  3. Normal values of 24-hour ambulatory esophageal impedance-pH monitoring in a rural South African cohort of healthy participants.

    PubMed

    Ndebia, E J; Sammon, A M; Umapathy, E; Iputo, J E

    2016-05-01

    There are no data on 24-hour multichannel intraluminal impedance and pH monitoring in African populations. The purpose of this study was to provide the normal values of esophageal impedance and pH monitoring in a rural African populations. South African healthy rural participants were recruited and underwent 24 hours of esophageal impedance and pH monitoring. The median and the 95th percentiles of the total reflux episodes were 49 and 97, respectively, of which the corresponding number of acidic, weakly acidic, and weakly alkaline reflux were 15 and 55, 17 and 51, and 8 and 36, respectively. The compositions of the total reflux were 5 and 21 for liquid, 27 and 72 for mixed, and 10 and 39 for gas reflux, respectively. The median bolus clearance was 18 seconds and the median bolus exposure was 14 minutes/24 hours. The proximal extent was 6%. The 95th percent time of esophageal exposure to acid was 8.6 in 24 hours. Female and overweight participants were associated with an increased number of reflux events. There were more reflux episodes, and of which, more were weakly alkaline compared with previous similar studies. The findings provide reference values of gastroesophageal reflux for a South African rural population. PMID:25721534

  4. 24-HOUR DIFFUSIVE SAMPLING OF 1,3-BUTADIENE IN AIR ONTO CARBONPAK X SOLID ADSORBENT WITH THEMAL DESORPTION/GC/MS ANALYSIS - FEASIBILITY STUDIES

    EPA Science Inventory

    Diffusive sampling of 1,3-butadiene for 24 hours onto the graphitic adsorbent Carbopack X contained in a stainless steel tube badge (6.3 mm OD, 5 mm ID, and 90 mm in length) with analysis by thermal desorption/GC/MS has been evaluated in controlled tests. A test matrix of 42 tr...

  5. Characterization of pulmonary protein profiles in response to zinc oxide nanoparticles in mice: a 24-hour and 28-day follow-up study.

    PubMed

    Pan, Chih-Hong; Chuang, Kai-Jen; Chen, Jen-Kun; Hsiao, Ta-Chih; Lai, Ching-Huang; Jones, Tim P; BéruBé, Kelly A; Hong, Gui-Bing; Ho, Kin-Fai; Chuang, Hsiao-Chi

    2015-01-01

    Although zinc oxide nanoparticles (ZnONPs) are recognized to cause systemic disorders, little is known about the mechanisms that underlie the time-dependent differences that occur after exposure. The objective of this study was to investigate the mechanistic differences at 24 hours and 28 days after the exposure of BALB/c mice to ZnONPs via intratracheal instillation. An isobaric tag for the relative and absolute quantitation coupled with liquid chromatography/tandem mass spectrometry was used to identify the differential protein expression, biological processes, molecular functions, and pathways. A total of 18 and 14 proteins displayed significant changes in the lung tissues at 24 hours and 28 days after exposure, respectively, with the most striking changes being observed for S100-A9 protein. Metabolic processes and catalytic activity were the main biological processes and molecular functions, respectively, in the responses at the 24-hour and 28-day follow-up times. The glycolysis/gluconeogenesis pathway was continuously downregulated from 24 hours to 28 days, whereas detoxification pathways were activated at the 28-day time-point after exposure. A comprehensive understanding of the potential time-dependent effects of exposure to ZnONPs was provided, which highlights the metabolic mechanisms that may be important in the responses to ZnONP. PMID:26251593

  6. 49 CFR 375.607 - What must I do if I am able to tender a shipment for final delivery more than 24 hours before a...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false What must I do if I am able to tender a shipment... INTERSTATE COMMERCE; CONSUMER PROTECTION REGULATIONS Transportation of Shipments § 375.607 What must I do if I am able to tender a shipment for final delivery more than 24 hours before a specified date?...

  7. The effect of low level radiofrequency electromagnetic radiation on the excretion rates of stress hormones in operators during 24-hour shifts.

    PubMed

    Vangelova, K; Israel, M; Mihaylov, S

    2002-06-01

    The aim of the study was to investigate the effect of long term exposure to low level radiofrequency (RF) electromagnetic (EM) radiation on the excretion rates of stress hormones in satellite station operators during 24-hour shifts. Twelve male operators at a satellite station for TV communications and space research were studied during 24-hour shifts. Dosimetric evaluation of the exposure was carried out and showed low level exposure with specific absorption of 0.1127 J.kg-1. A control group of 12 unexposed male operators with similar job task and the same shift system were studied, too. The 11-oxycorticosteroids (11-OCS), adrenaline and noradrenaline were followed by spectrofluorimetric methods on 3-hour intervals during the 24-hour shifts. The data were analyzed by tests for interindividual analysis, Cosinor analysis and analysis of variance (ANOVA). Significant increase in the 24-hour excretion of 11-OCS and disorders in its circadian rhythm, manifested by increase in the mesor, decrease in the amplitude and shift in the acrophase were found in the exposed operators. The changes in the excretion rates of the catecholamines were significant and showed greater variability of both variables. The long term effect of the exposure to low-level RF EM radiation evoked pronounced stress reaction with changes in the circadian rhythm of 11-OCS and increased variability of catecholamines secretion. The possible health hazards associated with observed alteration in the stress system need to be clarified by identification of their significance and prognostic relevance. PMID:12096679

  8. The Automated Self-Administered 24-hour dietary recall (ASA24): A resource for researchers, clinicians, and educators from the National Cancer Institute

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive evidence has demonstrated that 24-hour dietary recalls (24HDRs) provide high-quality dietary intake data with minimal bias, making them the preferred tool for monitoring the diets of populations and, increasingly, for studying diet and disease associations. Traditional 24HDRs, however, are...

  9. Screening for proteinuria in a rheumatology clinic: comparison of dipstick testing, 24 hour urine quantitative protein, and protein/creatinine ratio in random urine samples.

    PubMed

    Ralston, S H; Caine, N; Richards, I; O'Reilly, D; Sturrock, R D; Capell, H A

    1988-09-01

    Measurements of protein/creatinine ratio in 'spot' urine samples were compared with measurements of 24 hour quantitative proteinuria and side room 'dipstick' testing in 104 samples from 90 patients presenting consecutively to a rheumatology unit. Linear regression analysis showed a highly significant correlation between the random urinary protein/creatinine ratio and total protein excretion in 24 hour urine samples (r = 0.92, p less than 0.001, y = 6.55x + 0.04). Although an approximation of 24 hour urinary protein excretion could have been made from the regression line: 24 hour urine protein = 6.55 x protein/creatinine ratio + 0.04 (g/l), there was a wide scatter of values, particularly in patients with greater than 1 g/24 h urinary protein excretion. Nevertheless, significant proteinuria (greater than 300 mg/24 h) could have been confirmed or excluded with a sensitivity and specificity of 97% by adopting random protein/creatinine values of less than 0.04 as 'normal'. Specificity and sensitivity could have been increased to 100%, however, by excluding patients with values lying between 0.01 and 0.10 as all the false negatives (n = 3) and false positives (n = 3) lay within this range. In comparison, dipstick testing, although 100% sensitive, had a poor specificity due to the high false positive rate (40/83 (48%] in patients with 1+ to 3+ readings. Assessment of random urinary protein/creatinine ratio may obviate the need for 24 hour urine collections in the initial assessment of suspected proteinuria. A wider application of this technique seems indicated in view of the obvious advantages in terms of cost, time, and patient convenience. PMID:3263087

  10. Interventricular Septum and Posterior Wall Thickness Are Associated With Higher Systolic Blood Pressure.

    PubMed

    Eliakim-Raz, Noa; Prokupetz, Alex; Gordon, Barak; Shochat, Tzippy; Grossman, Alon

    2016-07-01

    Elevated blood pressure (BP) is a known factor that affects the structure of the left ventricle. The association between left ventricular hypertrophy (LVH) and BP in normotensive individuals is poorly understood. All individuals who underwent routine echocardiography and BP measurements as aircrew candidates for the Israeli Air Force in the years 2006 to 2012 were identified. Participants with normal values were included. Associations between echocardiographic characteristics and BP were studied. A total of 2386 participants were included. Mean systolic BP was 125.31±11.18 mm Hg and mean diastolic BP was 68.69±9.02 mm Hg. Interventricular septal (IVS) thickness was positively correlated with systolic BP (P<.001, correlation coefficient 0.121) and significantly inversely correlated with heart rate and hematocrit level (P<.001 for both). Men with evidence of IVS or posterior wall thickening on echocardiography, even within the normal range, may require a closer follow-up of BP. PMID:26607051

  11. Systolic systems: algorithms and complexity

    SciTech Connect

    Chang, J.H.

    1986-01-01

    This thesis has two main contributions. The first is the design of efficient systolic algorithms for solving recurrence equations, dynamic programming problems, scheduling problems, as well as new systolic implementation of data structures such as stacks, queues, priority queues, and dictionary machines. The second major contribution is the investigation of the computational power of systolic arrays in comparison to sequential models and other models of parallel computation.

  12. Review of isolated systolic hypertension in older adults.

    PubMed

    Kamath, Neetha; Cappuzzo, Kimberly A

    2010-06-01

    A 75-year-old patient comes to a community pharmacy to refill her blood pressure (BP) medications. She approached the pharmacist complaining of a headache and an unusually high BP reading that she had gotten from the automated machine. The patient was unaware of her usual BP, but knew that the reading was unusually high for her. Following evaluation of the patient and after obtaining several high systolic BP readings, the pharmacist appropriately calls for an ambulance. At the hospital, the patient is told she is in need of triple-bypass surgery. After her hospital stay, the patient is now diligent about refilling her BP medications on time and consistently monitors and records her BP at home. Isolated systolic hypertension is a growing concern in older adults, and a large percentage of adults are not appropriately managed. Pharmacists play an active role in educating patients on the importance of high BP monitoring and adherence to minimize the risk of cardiovascular events. PMID:20534408

  13. Initial emergency department systolic blood pressure predicts left ventricular systolic function in acute decompensated heart failure.

    PubMed

    Styron, Joseph F; Jois-Bilowich, Preeti; Starling, Randall; Hobbs, Robert E; Kontos, Michael C; Pang, Peter S; Peacock, W Frank

    2009-01-01

    Ejection fraction (EF) is often unknown in patients who present with acute decompensated heart failure (ADHF). The objective of this study was to determine whether a patient's systolic blood pressure is associated with their left ventricular EF. This study was a retrospective chart review of all patients admitted to an emergency department (ED) observation unit from January 2002 to December 2004. A low EF was defined as <40%. Among 475 patients, the median age was 72 years, 53% were men, 40% were white, 59% were black, and 59% had a low EF. Patients with low EFs were more likely male ( P<.0001), with prior congestive heart disease ( P<.0001), longer QRS duration ( P<.0001), left bundle branch block ( P<.0001), and higher B-type natriuretic peptide ( P<.0001). The low EF group was less likely to have diabetes ( P<.0001). Adjusted odds ratios for an EF >or=40% were significant at all systolic blood pressure readings >120 mm Hg. Having an ED systolic BP >120 mm Hg is associated with significantly higher rates of preserved left ventricular systolic function in patients with ADHF. PMID:19187401

  14. Bit-level systolic arrays

    SciTech Connect

    De Groot, A.J.

    1989-01-01

    In this dissertation the author considered the design of bit - level systolic arrays where the basic computational unit consists of a simple one - bit logic unit, so that the systolic process is carried out at the level of individual bits. In order to pursue the foregoing research, several areas have been studied. First, the concept of systolic processing has been investigated. Several important algorithms were investigated and put into systolic form using graph-theoretic methods. The bit-level, word-level and block-level systolic arrays which have been designed for these algorithms exhibit linear speedup with respect to the number of processors and exhibit efficiency close to 100%, even with low interprocessor communication bandwidth. Block-level systolic arrays deal with blocks of data with block-level operations and communications. Block-level systolic arrays improve cell efficiency and are more efficient than their word-level counterparts. A comparison of bit-level, word-level and block-level systolic arrays was performed. In order to verify the foregoing theory and analysis a systolic processor called the SPRINT was developed to provide and environment where bit-level, word-level and block-level systolic algorithms could be confirmed by direct implementation rather than by computer simulation. The SPRINT is a supercomputer class, 64-element multiprocessor with a reconfigurable interconnection network. The theory has been confirmed by the execution on the SPRINT of the bit-level, word-level, and block-level systolic algorithms presented in the dissertation.

  15. A systolic array parallelizing compiler

    SciTech Connect

    Tseng, P.S. )

    1990-01-01

    This book presents a completely new approach to the problem of systolic array parallelizing compiler. It describes the AL parallelizing compiler for the Warp systolic array, the first working systolic array parallelizing compiler which can generate efficient parallel code for complete LINPACK routines. This book begins by analyzing the architectural strength of the Warp systolic array. It proposes a model for mapping programs onto the machine and introduces the notion of data relations for optimizing the program mapping. Also presented are successful applications of the AL compiler in matrix computation and image processing. A complete listing of the source program and compiler-generated parallel code are given to clarify the overall picture of the compiler. The book concludes that systolic array parallelizing compiler can produce efficient parallel code, almost identical to what the user would have written by hand.

  16. A systolic radiation monitoring system

    SciTech Connect

    Shpancer, I.; Kinsner, W.

    1982-12-01

    This paper describes a data acquisition system for radiation monitoring which significantly improves performance over conventional systems by providing higher throughput, elimination of data skew, easier and inexpensive isolation, improved system accuracy, and compact implementation. The novel systolic data acquisition system, including systolic converter, processor and networking was developed to alleviate drawbacks of various conventional data acquisition systems used in radiation monitoring. The system is based on a systolic conversion, processing and networking method amenable to highly integrated vector architecture. The method employs systolic rules which can be developed for a selected problem. The rules for the radiation monitoring problem have been developed so as to apply not only locally but also globally to the systolic network. A form of the network has been implemented and is operational in a nuclear reactor site. Other forms are being implemented and tested for other data skew sensitive problems.

  17. Factors Associated With High Sodium Intake Based on Estimated 24-Hour Urinary Sodium Excretion: The 2009-2011 Korea National Health and Nutrition Examination Survey.

    PubMed

    Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

    2016-03-01

    Although reducing dietary salt consumption is the most cost-effective strategy for preventing progression of cardiovascular and renal disease, policy-based approaches to monitor sodium intake accurately and the understanding factors associated with excessive sodium intake for the improvement of public health are lacking. We investigated factors associated with high sodium intake based on the estimated 24-hour urinary sodium excretion, using data from the 2009 to 2011 Korea National Health and Nutrition Examination Survey (KNHANES). Among 21,199 adults (≥19 years of age) who participated in the 2009 to 2011 KNHANES, 18,000 participants (weighted n = 33,969,783) who completed urinary sodium and creatinine evaluations were analyzed in this study. The 24-hour urinary sodium excretion was estimated using Tanaka equation. The mean estimated 24-hour urinary sodium excretion level was 4349 (4286-4413) mg per day. Only 18.5% (weighted n = 6,298,481/3,396,973, unweighted n = 2898/18,000) of the study participants consumed less the 2000 mg sodium per day. Female gender (P < 0.001), older age (P < 0.001), total energy intake ≥50 percentile (P < 0.005), and obesity (P < 0.001) were associated with high sodium intake, even after adjusting for potential confounders. Senior high school/college graduation in education and managers/professionals in occupation were associated with lower sodium intake (P < 0.001). According to hypertension management status, those who had hypertension without medication consumed more sodium than those who were normotensive. However, those who receiving treatment for hypertension consumed less sodium than those who were normotensive (P < 0.001). The number of family members, household income, and alcohol drinking did not affect 24-hour urinary sodium excretion. The logistic regression analysis for the highest estimated 24-hour urinary sodium excretion quartile (>6033 mg/day) using the abovementioned variables

  18. Systolic architecture for heirarchical clustering

    SciTech Connect

    Ku, L.C.

    1984-01-01

    Several hierarchical clustering methods (including single-linkage complete-linkage, centroid, and absolute overlap methods) are reviewed. The absolute overlap clustering method is selected for the design of systolic architecture mainly due to its simplicity. Two versions of systolic architectures for the absolute overlap hierarchical clustering algorithm are proposed: one-dimensional version that leads to the development of a two dimensional version which fully takes advantage of the underlying data structure of the problems. The two dimensional systolic architecture can achieve a time complexity of O(m + n) in comparison with the conventional computer implementation of a time complexity of O(m/sup 2*/n).

  19. Systolic algorithms and their implementation

    SciTech Connect

    Kung, H.T.

    1984-01-01

    Very high performance computer systems must rely heavily on parallelism since there are severe physical and technological limits on the ultimate speed of any single processor. The systolic array concept developed in the last several years allows effective use of a very large number of processors in parallel. This article illustrates the basic ideas by reviewing a systolic array design for matrix triangularization and describing its use in the on-the-fly updating of Cholesky decomposition of covariance matrices-a crucial computation in adaptive signal processing. Following this are discussions on issues related to the hardware implementation of systolic algorithms in general, and some guidelines for designing systolic algorithms that will be convenient for implementation. 33 references.

  20. Development and validity of a 3-day smartphone-assisted 24-hour recall to assess beverage consumption in a Chinese population: a randomized cross-over study

    PubMed Central

    Smith, Lindsey P.; Hua, Jenna; Seto, Edmund; Du, Shufa; Zang, Jiajie; Zou, Shurong; Popkin, Barry M.; Mendez, Michelle A.

    2014-01-01

    This paper addresses the need for diet assessment methods that capture the rapidly changing beverage consumption patterns in China. The objective of this study was to develop a 3-day smartphone-assisted 24-hour recall to improve the quantification of beverage intake amongst young Chinese adults (n=110) and validate, in a small subset (n=34), the extent to which the written record and smartphone-assisted recalls adequately estimated total fluid intake, using 24-hour urine samples. The smartphone-assisted method showed improved validity compared to the written-assisted method, when comparing reported total fluid intake to total urine volume. However, participants reported consuming fewer beverages on the smartphone-assisted method compared to the written-assisted method, primarily due to decreased consumption of traditional zero-energy beverages (i.e. water, tea) in the smartphone-assisted method. It is unclear why participants reported fewer beverages in the smartphone-assisted method than the written-assisted method. One possibility is that participants found the smartphone method too cumbersome, and responded by decreasing beverage intake. These results suggest that smartphone-assisted 24-hour recalls perform comparably but do not appear to substantially improve beverage quantification compared to the current written record based approach. In addition, we piloted a beverage screener to identify consumers of episodically consumed SSBs. As expected, a substantially higher proportion of consumers reported consuming SSBs on the beverage screener compared to either recall type, suggesting that a beverage screener may be useful in characterizing consumption of episodically consumed beverages in China’s dynamic food and beverage landscape. PMID:25516327

  1. Decreased striatal dopamine release underlies increased expression of long-term synaptic potentiation at corticostriatal synapses 24 hours after 3-nitropropionic acid induced chemical hypoxia

    PubMed Central

    Akopian, Garnik; Crawford, Cynthia; Beal, M. Flint; Cappelletti, Maurand; Jakowec, Michael W.; Petzinger, Giselle M.; Zheng, Ling; Gheorghe, Stacey L.; Reichel, Carmela M.; Chow, Robert; Walsh, John P

    2008-01-01

    The striatum is particularly sensitive to the irreversible inhibitor of succinate dehyrdrogenase 3-nitropropionic acid (3-NP). In the present study we examined early changes in behavior and dopamine and glutamate synaptic physiology created by a single systemic injection of 3-NP in Fischer 344 rats. Hind limb dystonia was seen 2 hours after 3-NP injections and rats performed poorly on balance beam and rota-rod motor tests 24 hours later. Systemic 3-NP increased NMDA receptor-dependent long-term potentiation (LTP) at corticostriatal synapses over the same time period. The 3-NP induced corticostriatal LTP was not due to increased NMDA receptor number or function, since 3-NP did not change MK-801 binding or NMDA/AMPA receptor current ratios. The LTP seen 24 hours after 3-NP was D1 receptor-dependent and reversed by exogenous addition of dopamine or a D2 receptor agonist to brain slices. High performance liquid chromatography and fast scan cyclic voltammetry revealed a decrease in dopamine content and release in rats injected 24 hours earlier with 3-NP, and much like the enhanced LTP, dopamine changes were reversed by 48 hours. Tyrosine hydroxylase expression was not changed and there was no evidence of striatal cell loss at 24–48 hours after 3-NP exposure. Sprague-Dawley rats showed similar physiological responses to systemic 3-NP, albeit with reduced sensitivity. Thus, 3-NP causes significant changes in motor behavior marked by parallel changes in striatal dopamine release and corticostriatal synaptic plasticity. PMID:18799690

  2. Broadcast normalization in systolic design

    SciTech Connect

    Lin, F.C. ); Wu, I.C. )

    1988-11-01

    When a sequential algorithm is directly mapped into an array of processing elements, quite likely data broadcasts are required and their source places vary during the computation. The authors introduce a normalization method to fix the positions of the broadcast sources so that the derived design can be further transformed by retimings into a systolic array. The authors' method is fully illustrated in designing systolic arrays for enumeration sort, solving simultaneous linear equations, and computing transitive closure.

  3. Dynamically Reconfigurable Systolic Array Accelorators

    NASA Technical Reports Server (NTRS)

    Dasu, Aravind (Inventor); Barnes, Robert C. (Inventor)

    2014-01-01

    A polymorphic systolic array framework that works in conjunction with an embedded microprocessor on an FPGA, that allows for dynamic and complimentary scaling of acceleration levels of two algorithms active concurrently on the FPGA. Use is made of systolic arrays and hardware-software co-design to obtain an efficient multi-application acceleration system. The flexible and simple framework allows hosting of a broader range of algorithms and extendable to more complex applications in the area of aerospace embedded systems.

  4. Treatment of burns in the first 24 hours: simple and practical guide by answering 10 questions in a step-by-step form

    PubMed Central

    2012-01-01

    Residents in training, medical students and other staff in surgical sector, emergency room (ER) and intensive care unit (ICU) or Burn Unit face a multitude of questions regarding burn care. Treatment of burns is not always straightforward. Furthermore, National and International guidelines differ from one region to another. On one hand, it is important to understand pathophysiology, classification of burns, surgical treatment, and the latest updates in burn science. On the other hand, the clinical situation for treating these cases needs clear guidelines to cover every single aspect during the treatment procedure. Thus, 10 questions have been organised and discussed in a step-by-step form in order to achieve the excellence of education and the optimal treatment of burn injuries in the first 24 hours. These 10 questions will clearly discuss referral criteria to the burn unit, primary and secondary survey, estimation of the total burned surface area (%TBSA) and the degree of burns as well as resuscitation process, routine interventions, laboratory tests, indications of Bronchoscopy and special considerations for Inhalation trauma, immediate consultations and referrals, emergency surgery and admission orders. Understanding and answering the 10 questions will not only cover the management process of Burns during the first 24 hours but also seems to be an interactive clear guide for education purpose. PMID:22583548

  5. Effect of current and lifetime posttraumatic stress disorder on 24-hour urinary catecholamines and cortisol: results from the Mind Your Heart Study

    PubMed Central

    Wingenfeld, Katja; Whooley, Mary A.; Neylan, Thomas C.; Otte, Christian; Cohen, Beth E.

    2014-01-01

    Summary Posttraumatic stress disorder (PTSD) is associated with an increased risk of cardiovascular disease and several other chronic illnesses. Alterations in the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenal (HPA) axis in PTSD might contribute to these associations but findings regarding SNS and HPA activity in PTSD are heterogeneous. We measured 24-hour urinary catecholamines and cortisol in a large cohort of adult outpatients recruited from 2 Veterans Affairs medical centers. 24-hour urinary norepinephrine, epinephrine, dopamine and cortisol were measured by tandem mass spectrometry. Lifetime and current PTSD were assessed with the Clinician Administered PTSD Scale using DSM-IV-TR criteria. Out of 613 participants, 199 (32.5%) had current PTSD, 100 (16.3%) had lifetime but not current PTSD, and 314 (51.2%) never had PTSD. Patients with current PTSD had significantly higher norepinephrine secretion compared to those without PTSD. Patients in the lifetime PTSD group exhibited lower cortisol values compared to those without PTSD. Participants who never had PTSD showed the lowest norepinephrine and the highest cortisol values. All results remained stable when controlling for potentially confounding variables. This study provides evidence for increased norepinephrine secretion and decreased cortisol in PTSD. Future longitudinal studies are needed to determine whether these changes contribute to adverse health outcomes in patients with PTSD. PMID:25459895

  6. Estimation of 24-hour thyroid uptake of I-131 sodium iodide using a 5-minute uptake of technetium-99m pertechnetate

    SciTech Connect

    Smith, J.J.; Croft, B.Y.; Brookeman, V.A.; Teates, C.D. )

    1990-02-01

    The authors have developed a method to estimate the 24-hour sodium iodide thyroid uptake based on a 5-minute Tc-99m pertechnetate thyroid uptake using the equation: Estimated Iodide Uptake = 17.72*In(Pertechnetate Uptake) + 30.40. This estimation has a correlation coefficient of 0.90. It is based on a data pool of 44 patients who underwent I-131 and Tc-99m studies within 2 weeks of each other from 1978-1988, with established diagnoses as follows: 12 euthyroid, 6 hyperthyroid with multinodular goiters, 15 hyperthyroid with diffuse goiters, 4 with subacute thyroiditis, and 7 unknown. The population consisted of 30 women and 14 men with a mean age of 52.0 +/- 17.5 years; this sample was screened for use of thyroid hormone, propylthiouracil, and radiographic contrast. The authors believe this estimation method is of value whenever a 24-hour iodide uptake is desired, and where speed and minimizing radiation dose are factors. This method is strongly recommended for thyroid uptake evaluation before I-131 therapy.

  7. Estimate of the time zero lung burden of depleted uranium in Persian Gulf War veterans by the 24-hour urinary excretion and exponential decay analysis.

    PubMed

    Durakovic, Asaf; Horan, Patricia; Dietz, Leonard A; Zimmerman, Isaac

    2003-08-01

    The aim of this study was to estimate the amount of depleted uranium (DU) in the respiratory system of Allied Forces Gulf War Veterans. Mass spectrometry (thermal ionization mass spectrometry) analysis of 24-hour urinary excretion of DU isotopes in five positive (238U/235U > 191.00) and six negative (238U/235U > 138.25) veterans was utilized in the mathematical estimation of the pulmonary burden at the time of exposure. A minimum value for the biological half-life of ceramic DU oxide in the lungs was derived from the Battelle report of the minimum dissolution half-time in simulated interstitial lung fluid corresponding to 3.85 years. The average DU concentration was 3.27 x 10(-5) mg per 24 hours in DU-positive veterans and 1.46 x 10(-8) mg in DU-negative veterans. The estimated lung burden was 0.34 mg in the DU-positive and 0.00015 mg in the DU-negative veterans. Our results provide evidence that the pulmonary concentration of DU at time zero can be quantitated as late as 9 years after inhalational exposure. PMID:12943033

  8. Prognostic factors for death and survival with or without complications in cardiac arrest patients receiving CPR within 24 hours of anesthesia for emergency surgery

    PubMed Central

    Siriphuwanun, Visith; Punjasawadwong, Yodying; Lapisatepun, Worawut; Charuluxananan, Somrat; Uerpairojkit, Ketchada

    2014-01-01

    Purpose To determine prognostic factors for death and survival with or without complications in cardiac arrest patients who received cardiopulmonary resuscitation (CPR) within 24 hours of receiving anesthesia for emergency surgery. Patients and methods A retrospective cohort study approved by the Maharaj Nakorn Chiang Mai University Hospital Ethical Committee. Data used were taken from records of 751 cardiac arrest patients who received their first CPR within 24 hours of anesthesia for emergency surgery between January 1, 2003 and October 31, 2011. The reviewed data included patient characteristics, surgical procedures, American Society of Anesthesiologist (ASA) physical status classification, anesthesia information, the timing of cardiac arrest, CPR details, and outcomes at 24 hours after CPR. Univariate and polytomous logistic regression analyses were used to determine prognostic factors associated with the outcome variable. P-values of less than 0.05 were considered statistically significant. Results The outcomes at 24 hours were death (638/751, 85.0%), survival with complications (73/751, 9.7%), and survival without complications (40/751, 5.3%). The prognostic factors associated with death were: age between 13–34 years (OR =3.08, 95% CI =1.03–9.19); ASA physical status three and higher (OR =6.60, 95% CI =2.17–20.13); precardiopulmonary comorbidity (OR =3.28, 95% CI =1.09–9.90); the condition of patients who were on mechanical ventilation prior to receiving anesthesia (OR =4.11, 95% CI =1.17–14.38); surgery in the upper abdominal site (OR =14.64, 95% CI =2.83–75.82); shock prior to cardiac arrest (OR =6.24, 95% CI =2.53–15.36); nonshockable electrocardiography (EKG) rhythm (OR =5.67, 95% CI =1.93–16.62); cardiac arrest occurring in postoperative period (OR =7.35, 95% CI =2.89–18.74); and duration of CPR more than 30 minutes (OR =4.32, 95% CI =1.39–13.45). The prognostic factors associated with survival with complications were being greater

  9. Dynamically Reconfigurable Systolic Array Accelerator

    NASA Technical Reports Server (NTRS)

    Dasu, Aravind; Barnes, Robert

    2012-01-01

    A polymorphic systolic array framework has been developed that works in conjunction with an embedded microprocessor on a field-programmable gate array (FPGA), which allows for dynamic and complimentary scaling of acceleration levels of two algorithms active concurrently on the FPGA. Use is made of systolic arrays and a hardware-software co-design to obtain an efficient multi-application acceleration system. The flexible and simple framework allows hosting of a broader range of algorithms, and is extendable to more complex applications in the area of aerospace embedded systems. FPGA chips can be responsive to realtime demands for changing applications needs, but only if the electronic fabric can respond fast enough. This systolic array framework allows for rapid partial and dynamic reconfiguration of the chip in response to the real-time needs of scalability, and adaptability of executables.

  10. Systoles in discrete dynamical systems

    NASA Astrophysics Data System (ADS)

    Fernandes, Sara; Grácio, Clara; Ramos, Carlos Correia

    2013-01-01

    The fruitful relationship between Geometry and Graph Theory has been explored by several authors benefiting also the Theory of discrete dynamical systems seen as Markov chains in graphs. In this work we will further explore the relation between these areas, giving a geometrical interpretation of notions from dynamical systems. In particular, we relate the topological entropy with the systole, here defined in the context of discrete dynamical systems. We show that for continuous interval maps the systole is trivial; however, for the class of interval maps with one discontinuity point the systole acquires relevance from the point of view of the dynamical behavior. Moreover, we define the geodesic length spectrum associated to a Markov interval map and we compute the referred spectrum in several examples.

  11. New Advantage 24 contraceptive gel claims 24-hour effectiveness. But proposed FDA rule could put N-9 products to the test.

    PubMed

    1995-04-01

    Advantage 24 is a new contraceptive gel that makes use of bioadhesive technology to offer 24 hours of protection relying on the spermicide nonoxynol-9 (N-9) in lower concentrations. If a proposed US Food and Drug Administration (FDA) rule is enforced N-9 may be examined closely. The manufacturer, Whitehall-Robins Healthcare in New Jersey, stopped production of the Today contraceptive sponge because of the costs of complying with FDA standards. The Advantage 24 gel costs twice as much as the sponge. It is made in Switzerland and distributed by an Illinois company. Any vaginal contraceptive containing N-9 would be approved by the FDA as long as it complied with guidelines laid down in an FDA monograph. However, the registration of the gel could not be confirmed. The product uses a bioadhesive technology concept that natural substances adhere to epithelial and mucosal tissues in the body. Polycarbofil is mixed with water, N-9, and mineral oil to create an emulsion that allows for a time-release mechanism, but at any given time only 2 mg of N-9 is available to kill sperm. The final formula for Advantage 24 is 52.5 mg per dose. Too much N-9 can be toxic, as demonstrated by the Today sponge, which contained 1000 mg of N-9. In Kenya prostitutes using it frequently experienced 3 times as many genital lesions as those using a placebo. A study of Advantage 24 by a Miami laboratory involved 250 women, 22-45 years old, who had had prior tubal ligations. When the gel was applied 15-30 minutes before intercourse the efficacy rate was 98%; it was 91% for those applying it 12 hours before; and it was 86% when the gel was applied 24 hours ahead of time. FDA compliance officers are intrigued about the claim that the gel lasts 24 hours. However, if the claim is held up by research data, women will have an easily available, portable, efficient, aesthetic, and highly effective contraceptive. PMID:12347026

  12. Proposal of RAS-diuretic vs. RAS-calcium antagonist strategies in high-risk hypertension: insight from the 24-hour ambulatory blood pressure profile and central pressure.

    PubMed

    Kario, Kazuomi

    2010-01-01

    I here propose an individualized renin angiotensin system (RAS) inhibitor-based combination therapy with calcium-channel blockers (CCBs) or with diuretics, based on the 24-hr ambulatory blood pressure (BP) profiles and central pressure in relation to the target organ damage in high-risk hypertensive patients. For high-risk patients with increased circulating volume, such as that caused by chronic kidney disease (CKD) or congestive heart failure (CHF), who are likely to exhibit a non-dipper/riser pattern of nocturnal BP fall, diuretics are recommended in combination with a RAS inhibitor to reduce nocturnal BP preferentially. For high-risk patients with arterial diseases such as cardiovascular disease and increased arterial stiffness, who are likely to exhibit exaggerated BP variability, such as morning BP surge and day-to-day BP variability, a CCB is recommended for use in combination with a RAS inhibitor to reduce BP variability and central BP. In particular, bedtime dosing of a RAS inhibitor targeting sleep-early morning activation of RAS may be particularly effective for cardiorenal protection. PMID:20728424

  13. Electronic Dietary Intake Assessment (e-DIA): Comparison of a Mobile Phone Digital Entry App for Dietary Data Collection With 24-Hour Dietary Recalls

    PubMed Central

    O'Connor, Sarah; Giannelli, Valentina; Yap, Megan LH; Tang, Lie Ming; Roy, Rajshri; Louie, Jimmy Chun Yu; Hebden, Lana; Kay, Judy; Allman-Farinelli, Margaret

    2015-01-01

    Background The electronic Dietary Intake Assessment (e-DIA), a digital entry food record mobile phone app, was developed to measure energy and nutrient intake prospectively. This can be used in monitoring population intakes or intervention studies in young adults. Objective The objective was to assess the relative validity of e-DIA as a dietary assessment tool for energy and nutrient intakes using the 24-hour dietary recall as a reference method. Methods University students aged 19 to 24 years recorded their food and drink intake on the e-DIA for five days consecutively and completed 24-hour dietary recalls on three random days during this 5-day study period. Mean differences in energy, macro-, and micronutrient intakes were evaluated between the methods using paired t tests or Wilcoxon signed-rank tests, and correlation coefficients were calculated on unadjusted, energy-adjusted, and deattenuated values. Bland-Altman plots and cross-classification into quartiles were used to assess agreement between the two methods. Results Eighty participants completed the study (38% male). No significant differences were found between the two methods for mean intakes of energy or nutrients. Deattenuated correlation coefficients ranged from 0.55 to 0.79 (mean 0.68). Bland-Altman plots showed wide limits of agreement between the methods but without obvious bias. Cross-classification into same or adjacent quartiles ranged from 75% to 93% (mean 85%). Conclusions The e-DIA shows potential as a dietary intake assessment tool at a group level with good ranking agreement for energy and all nutrients. PMID:26508282

  14. Demand and characteristics of a psychiatric 24-hour emergency service performed by mandatory rotation of licensed psychiatrists in Swiss primary care

    PubMed Central

    Chmiel, Corinne; Rosemann, Thomas; Senn, Oliver

    2014-01-01

    Background To investigate characteristics of and satisfaction with psychiatric 24-hour emergency primary care performed by mandatory rotation of licensed psychiatrists as a viable baseline for possible reorganizational measures. Methods This was a questionnaire-based cross-sectional study (November 2010–April 2011). The number of patient–psychiatrist encounters, modes of contact, and patient and psychiatrist characteristics were assessed. Diagnoses were coded with ICD-10 (International Classification of Diseases, version 10). Results From 167 duty episodes, 74 (44%) were recorded. Of the psychiatrists (n=44), 52% were female, and mean age (standard deviation) was 49.9 (5.2) years. The median number of encounters per episode was 4 (interquartile range 0–8), mainly in the evenings. Demand for “face-to-face” (direct) patient visits was significantly more common (64.0%) than practice (1.3%) or telephone consultations (34.7%). In 83.8%, psychiatrists judged the encounter as adequate at the patient’s location. A total of 43 different diagnoses were recorded: mainly schizophrenic disorders (23.9%), suicidal behavior (15.2%), and acute stress reactions (10.3%). Psychiatrists felt burdened by services (62.5%): in 39.2%, they felt threatened; and in 6.8%, violence occurred. In 32.4%, bills were not paid for. If services were optional, 45.2% would participate. Conclusion Our findings indicate justified demand for direct mobile patient visits, suggesting that emergency care should be multifaceted, and sole provision of psychiatric care at stationed emergency facilities may not always be appropriate. Reorganization of 24-hour emergency services should carefully evaluate patient and provider’s needs before changing established structures. PMID:24707172

  15. Correlation of Occupational Stress Index with 24-hour Urine Cortisol and Serum DHEA Sulfate among City Bus Drivers: A Cross-sectional Study

    PubMed Central

    Lin, Mia Chihya; Lu, Luo; Tai, John Jen

    2011-01-01

    Objectives The questionnaire of occupational stress index (OSI) has been popular in the workplace, and it has been tailored for bus drivers in Taiwan. Nevertheless, its outcomes for participants are based on self-evaluations, thus validation by their physiological stress biomarker is warranted and this is the main goal of this study. Methods A cross-sectional study of sixty-three city bus drivers and fifty-four supporting staffs for comparison was conducted. Questionnaire surveys, 24-hour urine cortisol testing, and blood draws for dehydroepiandrosterone-sulfate (DHEA-S) testing were performed. The measured concentrations of these biological measures were logarithmically transformed before the statistical analysis where various scores of stressor factors, moderators, and stress effects of each OSI domain were analyzed by applying multiple linear regression models. Results For drivers, the elevated 24-hour urine cortisol level was associated with a worker's relationship with their supervisor and any life change events in the most recent 3 months. The DHEA-S level was higher in drivers of younger age as well as drivers with more concerns relating to their salary and bonuses. Non-drivers showed no association between any stressor or satisfaction and urine cortisol and blood DHEA-S levels. Conclusion Measurements of biomarkers may offer additional stress evaluations with OSI questionnaires for bus drivers. Increased DHEA-S and cortisol levels may result from stressors like income security. Prevention efforts towards occupational stress and life events and health promotional efforts for aged driver were important anti-stress remedies. PMID:22953199

  16. Design of optimal systolic arrays

    SciTech Connect

    Li, G.J.; Wah, B.W.

    1985-01-01

    Conventional design of systolic arrays is based on the mapping of an algorithm onto an interconnection of processing elements in a VLSI chip. This mapping is done in an ad hoc manner, and the resulting configuration usually represents a feasible but suboptimal design. In this paper, systolic arrays are characterized by three classes of parameters: the velocities of data flows, the spatial distributions of data, and the periods of computation. By relating these parameters in constraint equations that govern the correctness of the design, the design is formulated into an optimization problem. The size of the search space is a polynomial of the problem size, and a methodology to systematically search and reduce this space and to obtain the optimal design is proposed. Some examples of applying the method, including matrix multiplication, finite impulse response filtering, deconvolution, and triangular-matrix inversion, are given. 30 references.

  17. Prediction of Appropriate Shocks Using 24-Hour Holter Variables and T-Wave Alternans After First Implantable Cardioverter-Defibrillator Implantation in Patients With Ischemic or Nonischemic Cardiomyopathy.

    PubMed

    Seegers, Joachim; Bergau, Leonard; Expósito, Pascal Muñoz; Bauer, Axel; Fischer, Thomas H; Lüthje, Lars; Hasenfuß, Gerd; Friede, Tim; Zabel, Markus

    2016-07-01

    In patients treated with implantable cardioverter defibrillator (ICD), prediction of both overall survival and occurrence of shocks is important if improved patient selection is desired. We prospectively studied the predictive value of biomarkers and indexes of cardiac and renal function and spectral microvolt T-wave alternans testing and 24-hour Holter variables in a population who underwent first ICD implantation. Consecutive patients in sinus rhythm with ischemic or dilated cardiomyopathy scheduled for primary or secondary prophylactic ICD implantation were enrolled. Exercise microvolt T-wave alternans and 24-hour Holter for number of ventricular premature contractions (VPCs), deceleration capacity, heart rate variability, and heart rate turbulence were done. Death of any cause and first appropriate ICD shock were defined as end points. Over 33 ± 15 months of follow-up, 36 of 253 patients (14%) received appropriate shocks and 39 of 253 patients (15%) died. Only 3 of 253 patients (1%) died after receiving at least 1 appropriate shock. In univariate analyses, New York Heart Association class, ejection fraction, N-terminal pro brain-type natriuretic peptide (NT-proBNP), renal function, ICD indication, deceleration capacity, heart rate variability, and heart rate turbulence were predictive of all-cause mortality and VPC number and deceleration capacity predicted first appropriate shock. NT-proBNP (≥1,600 pg/ml) was identified as the only independent predictor of all-cause mortality (hazard ratio 3.0, confidence interval 1.3 to 7.3, p = 0.014). In contrast, VPC number predicted appropriate shocks (hazard ratio 2.3, confidence interval 1.0 to 5.5, p = 0.047) as the only independent risk marker. In conclusion, NT-proBNP is a strong independent predictor of mortality in a typical prospective cohort of newly implanted patients with ICD, among many electrocardiographic and clinical variables studied. Number of VPCs was identified as a predictor of appropriate shocks

  18. Metabolic Engineering of Light and Dark Biochemical Pathways in Wild-Type and Mutant Strains of Synechocystis PCC 6803 for Maximal, 24-Hour Production of Hydrogen Gas

    SciTech Connect

    Ely, Roger L.; Chaplen, Frank W.R.

    2014-03-11

    This project used the cyanobacterial species Synechocystis PCC 6803 to pursue two lines of inquiry, with each line addressing one of the two main factors affecting hydrogen (H2) production in Synechocystis PCC 6803: NADPH availability and O2 sensitivity. H2 production in Synechocystis PCC 6803 requires a very high NADPH:NADP+ ratio, that is, the NADP pool must be highly reduced, which can be problematic because several metabolic pathways potentially can act to raise or lower NADPH levels. Also, though the [NiFe]-hydrogenase in PCC 6803 is constitutively expressed, it is reversibly inactivated at very low O2 concentrations. Largely because of this O2 sensitivity and the requirement for high NADPH levels, a major portion of overall H2 production occurs under anoxic conditions in the dark, supported by breakdown of glycogen or other organic substrates accumulated during photosynthesis. Also, other factors, such as N or S limitation, pH changes, presence of other substances, or deletion of particular respiratory components, can affect light or dark H2 production. Therefore, in the first line of inquiry, under a number of culture conditions with wild type (WT) Synechocystis PCC 6803 cells and a mutant with impaired type I NADPH-dehydrogenase (NDH-1) function, we used H2 production profiling and metabolic flux analysis, with and without specific inhibitors, to examine systematically the pathways involved in light and dark H2 production. Results from this work provided rational bases for metabolic engineering to maximize photobiological H2 production on a 24-hour basis. In the second line of inquiry, we used site-directed mutagenesis to create mutants with hydrogenase enzymes exhibiting greater O2 tolerance. The research addressed the following four tasks: 1. Evaluate the effects of various culture conditions (N, S, or P limitation; light/dark; pH; exogenous organic carbon) on H2 production profiles of WT cells and an NDH-1 mutant; 2. Conduct metabolic flux analyses for

  19. Shortening the retention interval of 24-hour dietary recalls increases fourth-grade children’s accuracy for reporting energy and macronutrient intake at school meals

    PubMed Central

    Guinn, Caroline H.; Royer, Julie A.; Hardin, James W.; Mackelprang, Alyssa J.; Smith, Albert F.

    2010-01-01

    Background Accurate information about children’s intake is crucial for national nutrition policy and for research and clinical activities. To analyze accuracy for reporting energy and nutrients, most validation studies utilize the conventional approach which was not designed to capture errors of reported foods and amounts. The reporting-error-sensitive approach captures errors of reported foods and amounts. Objective To extend results to energy and macronutrients for a validation study concerning retention interval (elapsed time between to-be-reported meals and the interview) and accuracy for reporting school-meal intake, the conventional and reporting-error-sensitive approaches were compared. Design and participants/setting Fourth-grade children (n=374) were observed eating two school meals, and interviewed to obtain a 24-hour recall using one of six interview conditions from crossing two target periods (prior-24-hours; previous-day) with three interview times (morning; afternoon; evening). Data were collected in one district during three school years (2004–2005; 2005–2006; 2006–2007). Main outcome measures Report rates (reported/observed), correspondence rates (correctly reported/observed), and inflation ratios (intruded/observed) were calculated for energy and macronutrients. Statistical analyses performed For each outcome measure, mixed-model analysis of variance was conducted with target period, interview time, their interaction, and sex in the model; results were adjusted for school year and interviewer. Results Conventional approach — Report rates for energy and macronutrients did not differ by target period, interview time, their interaction, or sex. Reporting-error-sensitive approach — Correspondence rates for energy and macronutrients differed by target period (four P-values<0.0001) and the target-period by interview-time interaction (four P-values<0.0001); inflation ratios for energy and macronutrients differed by target period (four P

  20. [Arterial hypertension in special situations: mild, systolic and in pregnancy].

    PubMed

    Luque Otero, M; Fernández Pinilla, C

    1990-01-01

    Mild hypertension is very common, 50% of hypertensives being with their diastolic BP between 90 and 104 mmHg. Many large studies, especially HDFP, had shown not only the deleterious cardiovascular effects of mild hypertension but also the benefits obtained with the therapy. The non-pharmacological approach should be the first step in the treatment of mild hypertension. Isolated systolic hypertension have a high prevalence in the elderly, increasing the cardiovascular morbidity and mortality. Sodium restriction and, if necessary, vasodilators increasing the arterial compliance seem to be the logical approach to treat isolated systolic hypertension. Finally, eclampsia is the most serious complication of pregnancy - induced hypertension. The treatment with bed rest and either betablockers or methyldopa is beneficial. If eclampsia occurs hydralazine, magnesium sulphate or nifedipine should be used. PMID:2186454

  1. Control of bleeding by silk ligation and diathermy coagulation during tonsillectomy: A comparison of efficacy of the two techniques in the first 24 hours after surgery

    PubMed Central

    Anwar, Khurshid; Ahmad, Rafiq; Khan, Muneeb

    2015-01-01

    Objective: To assess and compare the relative efficacy of silk ligation and diathermy coagulation techniques in controlling bleeding during tonsillectomy in the first 24 hours. Methods: This prospective study was conducted at the Department of ENT, Khalifa Gul Nawaz Teaching Hospital, Bannu and this department related consultants’ private clinics from January 1, 2012 to December 31, 2014. The study included 180 cases. All patients included were having history of recurrent, acute tonsillitis, with more than 6–7 episodes in one year, five episodes per year for two years, or three episodes per year for three years. All the surgeries were performed by dissection method. Haemostasis during the procedure was secured by either ligation with silk 1 or using diathermy. The results were analyzed using SPSS 16.0 for windows. Results: A total of180 cases were included in the study. The ages of the patients ranged from 5 to 40 years with the mean age of 15.56 years and a std.deviation of +/- 8.24. The male to female ratio was 1.25:1. The number of hemorrhages occurring was greater in the ‘diathermy coagulation’ group as compared to the ‘silk ligation’ group. However, the observed difference was statistically insignificant (p >.05). Conclusion: Primary haemorrhage occurring during tonsillectomy is a serious threat and control of bleeding during the procedure should therefore be meticulous. Both suture ligation and coagulation diathermy for control of bleeders during the procedure by dissection method are equally effective. PMID:26430438

  2. A Day in the Life of Millisecond Pulsar J1713+0747: Limits on Timing Precision Over 24 Hours and Implications for Gravitational Wave Detection

    NASA Astrophysics Data System (ADS)

    Dolch, Timothy; Bailes, M.; Bassa, C.; Bhat, R.; Bhattacharyya, B.; Champion, D.; Chatterjee, S.; Cognard, I.; Cordes, J. M.; Crowter, K.; Demorest, P.; Finn, L. S.; Fonseca, E.; Hessels, J.; Hobbs, G.; Janssen, G.; Jones, G.; Jordan, C.; Karuppusamy, R.; Keith, M.; Kramer, M.; Kraus, A.; Lam, M. T.; Lazarus, P.; Lazio, J.; Lee, K.; Levin, L.; Liu, K.; Lorimer, D.; Manchester, R. N.; McLaughlin, M.; Palliyaguru, N.; Perrodin, D.; Petroff, E.; Rajwade, K.; Rankin, J. M.; Ransom, S. M.; Rosenblum, J.; Roy, J.; Shannon, R.; Stappers, B.; Stinebring, D.; Stovall, K.; Teixeira, M.; van Leeuwen, J.; van Straten, W.; Verbiest, J.; Zhu, W.

    2014-01-01

    A 24-hour global observation of millisecond radio pulsar J1713+0747 was undertaken by the International Pulsar Timing Array (IPTA) collaboration as an effort to better quantify sources of noise in this object, which is regularly timed for the purpose of detecting gravitational waves (GWs). Given an 8-year timing RMS of 30ns, it is regarded as one of the best precision clocks in the PTA. However, sources of timing noise visible on timescales longer than the usual 20-30min biweekly observation may nonetheless be present. Data from the campaign were taken contiguously with the Parkes, Arecibo, Green Bank, GMRT, LOFAR, Effelsberg, WSRT, Lovell, and Nancay radio telescopes. The combined pulse times-of-arrival provide an estimate of the absolute noise floor, in other words, what unaccounted sources of timing noise impede an otherwise simple sqrt(N) improvement in timing precision, where N is the number of pulses in a single observing session. We present first results of specific phenomena probed on the unusual timescale of tens of hours, in particular interstellar scattering (ISS), and discuss the degree to which ISS affects precision timing. Finally, we examine single pulse information during selected portions of the observation and determine the degree to which the pulse jitter of J1713+0747 varies throughout the course of the day-long dataset.

  3. Canadian 24-Hour Movement Guidelines for Children and Youth: Exploring the perceptions of stakeholders regarding their acceptability, barriers to uptake, and dissemination.

    PubMed

    Faulkner, Guy; White, Lauren; Riazi, Negin; Latimer-Cheung, Amy E; Tremblay, Mark S

    2016-06-01

    Engaging stakeholders in the development of guidelines and plans for implementation is vital. The purpose of this study was to examine stakeholders' (parents, teachers, exercise professionals, paediatricians, and youth) perceptions of the Canadian 24-Hour Movement Behaviour Guidelines for Children and Youth ("Movement Guidelines"). Stakeholders (n = 104) engaged in semi-structured focus groups or interviews to discuss the perceived acceptability of the guidelines, potential barriers to implementation, and preferred methods and messengers of dissemination. A thematic analysis was conducted. Overall, there was consistent support across all stakeholder groups, with the exception of youth participants, for the Movement Guidelines. Stakeholders identified a range of barriers to the uptake of the guidelines including concerns with accurately defining key terms such as "recreational" screen time; everyday challenges such as financial and time constraints; and the possibility of the Movement Guidelines becoming just another source of stress and guilt for already busy and overwhelmed parents. Participants identified a range of recommended methods and messengers for future dissemination. School and medical settings were the most commonly recommended settings through which dissemination efforts should be delivered. Overall, participants representing a range of stakeholder groups were receptive to the new Movement Guidelines and endorsed their value. In complementing the Movement Guidelines, messaging and resources will need to be developed that address common concerns participants had regarding their dissemination and implementation. PMID:27306436

  4. Tele-ECG and 24-hour physician support over telephone for rural doctors can help early treatment of acute myocardial infarction in rural areas.

    PubMed

    Vivek, Chauhan; Vikrant, Kanwar

    2016-04-01

    We observed that many patients of acute myocardial infarction (AMI) were reaching our hospital out of the 12 hour window period for thrombolysis. This led to poor patient outcomes. There were multiple reasons for the delay, prominent among them was lack of diagnostic facilities in the rural health care centers. We therefore planned a Tele-Electrocardiography (Tele-ECG) based pilot project in Kangra District of Himachal Pradesh in India, which was funded by the Indian Council of Medical Research. The intention was to reduce the pre-hospital delay in AMI by enabling the rural doctors of Kangra using Tele-ECG facility and a 24-hour physician support to manage patients of AMI. We did a baseline knowledge, attitude, and practice (KAP) assessment study of the doctors in our intervention centers to understand their needs. The data obtained through the KAP study was an eye opener for us and justifies the need for a Tele-ECG facility for rural doctors in India. PMID:26187625

  5. Intersalt: an international study of electrolyte excretion and blood pressure. Results for 24 hour urinary sodium and potassium excretion. Intersalt Cooperative Research Group.

    PubMed Central

    1988-01-01

    The relations between 24 hour urinary electrolyte excretion and blood pressure were studied in 10,079 men and women aged 20-59 sampled from 52 centres around the world based on a highly standardised protocol with central training of observers, a central laboratory, and extensive quality control. Relations between electrolyte excretion and blood pressure were studied in individual subjects within each centre and the results of these regression analyses pooled for all 52 centres. Relations between population median electrolyte values and population blood pressure values were also analysed across the 52 centres. Sodium excretion ranged from 0.2 mmol/24 h (Yanomamo Indians, Brazil) to 242 mmol/24 h (north China). In individual subjects (within centres) it was significantly related to blood pressure. Four centres found very low sodium excretion, low blood pressure, and little or no upward slope of blood pressure with age. Across the other 48 centres sodium was significantly related to the slope of blood pressure with age but not to median blood pressure or prevalence of high blood pressure. Potassium excretion was negatively correlated with blood pressure in individual subjects after adjustment for confounding variables. Across centres there was no consistent association. The relation of sodium to potassium ratio to blood pressure followed a pattern similar to that of sodium. Body mass index and heavy alcohol intake had strong, significant independent relations with blood pressure in individual subjects. PMID:3416162

  6. Computer simulation of the effect of dDAVP with saline loading on fluid balance after 24-hour head-down tilt

    NASA Technical Reports Server (NTRS)

    Srinivasan, R. S.; Simanonok, K. E.; Charles, J. B.

    1994-01-01

    Fluid loading (FL) before Shuttle reentry is a countermeasure currently in use by NASA to improve the orthostatic tolerance of astronauts during reentry and postflight. The fluid load consists of water and salt tablets equivalent to 32 oz (946 ml) of isotonic saline. However, the effectiveness of this countermeasure has been observed to decrease with the duration of spaceflight. The countermeasure's effectiveness may be improved by enhancing fluid retention using analogs of vasopressin such as lypressin (LVP) and desmopressin (dDAVP). In a computer simulation study reported previously, we attempted to assess the improvement in fluid retention obtained by the use of LVP administered before FL. The present study is concerned with the use of dDAVP. In a recent 24-hour, 6 degree head-down tilt (HDT) study involving seven men, dDAVP was found to improve orthostatic tolerance as assessed by both lower body negative pressure (LBNP) and stand tests. The treatment restored Luft's cumulative stress index (cumulative product of magnitude and duration of LBNP) to nearly pre-bedrest level. The heart rate was lower and stroke volume was marginally higher at the same LBNP levels with administration of dDAVP compared to placebo. Lower heart rates were also observed with dDAVP during stand test, despite the lower level of cardiovascular stress. These improvements were seen with only a small but significant increase in plasma volume of approximately 3 percent. This paper presents a computer simulation analysis of some of the results of this HDT study.

  7. Heritability of HR and BP Response To Exercise Training in the HERITAGE Family Study.

    ERIC Educational Resources Information Center

    Rice, Treva; Gagnon, Jacques; Leon, Arthur S.; Skinner, James S.; Wilmore, Jack H.; Bouchard, Claude; Rao, D. C.

    2002-01-01

    Assessed the heritability of response to exercise training in resting blood pressure (BP) and heart rate (HR) among sedentary Caucasians comprising 98 families who completed an exercise training program. Results indicated that the trainability of systolic BP and HR in families with elevated BP was partially determined by genetic factors. Diastolic…

  8. Analysis of systolic and systolic-type arrays

    SciTech Connect

    Jover, J.M.

    1986-01-01

    Synchronous, multiprocessor systems interconnected by fixed links are studied. These special-purpose systems, called systolic-type arrays, perform specific algorithms at a higher throughput rate than the sequential architecture of van Neumann. The main contributions of this thesis are the analysis of systolic-type arrays, and the design of one such complex system. In the analysis problem the topology of the network, the function performed by each processor (including timing information), and the input data streams are given. I/O algorithm performed by the array, and the iteration interval (i.e., the time between two consecutive input samples) are to be determined. Solution to the analysis problem turns out to be based on the simple, at least in retrospect, observation that analysis is the reverse of synthesis (design). In design, the start is with a mathematical algorithm and a representation of it as a signal flow graph (SFG) in which the computations (function evaluations) are presented by delay-free (instantaneous) blocks and the index shifts in the sequences processed by the algorithm are all lumped into so-called z/sup -1/ blocks. In the analysis problem, start is also with a physical implementation described by its computational blocks, their associated processing times, and their interconnections. Also presented is parallel architecture for the measurement update step of the Kalman filter, which estimates a vector parameter.

  9. Systolic VLSI for Kalman filters

    NASA Technical Reports Server (NTRS)

    Yeh, H.-G.; Chang, J. J.

    1986-01-01

    A novel two-dimensional parallel computing method for real-time Kalman filtering is presented. The mathematical formulation of a Kalman filter algorithm is rearranged to be the type of Faddeev algorithm for generalizing signal processing. The data flow mapping from the Faddeev algorithm to a two-dimensional concurrent computing structure is developed. The architecture of the resulting processor cells is regular, simple, expandable, and therefore naturally suitable for VLSI chip implementation. The computing methodology and the two-dimensional systolic arrays are useful for Kalman filter applications as well as other matrix/vector based algebraic computations.

  10. "2001: A Space Odyssey" Revisited: The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners. Revised

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; Dudzinski, Leonard A.

    2001-01-01

    The prospects for "24 hour" commuter flights to the Moon. similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale. are examined using two near term. "high leverage" technologies-liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and "lunar-derived" oxygen (LUNOX) production. Iron-rich volcanic glass. or "orange soil," discovered during the Apollo 17 mission to Taurus-Littrow. has produced a 4% oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way. LANTR utilizes the large divergent section of its nozzle as an "afterburner" into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the engine's choked sonic throat-essentially "scramjet propulsion in reverse." By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that "big engine" performance can be obtained using smaller. more affordable. easier to test NTR engines. The use of high-density LOX in place of low-density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or "in-line" Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an "expendable mode" initially, to maximize delivered surface payload on each mission. The increased

  11. "2001: A Space Odyssey" Revisited--The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; Dudzinski, Leonard A.

    1998-01-01

    The prospects for "24 hour" commuter flights to the Moon, similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale, are examined using two near term, "high leverage" technologies--liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and "lunar-derived" oxygen (LUNOX) production. Ironrich volcanic glass, or "orange soil," discovered during the Apollo 17 mission to Taurus-Littrow, has produced a 4% oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way, LANTR utilizes the large divergent section of its nozzle as an "afterburner" into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging front the engine's choked sonic throat--essentially "scramjet propulsion in reverse." By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that "big engine" performance can be obtained using smaller, more affordable, easier to test NTR engines. The use of high-density LOX in place of low-density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or "in-line" Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an "expendable mode" initially, to maximize delivered surface payload on each mission. The increased

  12. 2001: A Space Odyssey Revisited: The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners. Revised

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley; Dudzinski, Leonard A.

    2003-01-01

    The prospects for 24 hour commuter flights to the Moon, similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale, are examined using two near term, high leverage technologies: liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and lunar-derived oxygen (LUNOX) production. Iron-rich volcanic glass, or orange soil, discovered during the Apollo 17 mission to Taurus-Littrow, has produced a 4 percent oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way. LANTR utilizes the large divergent section of its nozzle as an afterburner into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the engine's choked sonic throat, essentially scramjet propulsion in reverse. By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that big engine performance can be obtained using smaller, more affordable, easier to test NTR engines. The use of high-density LOX in place of low density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or in-line Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an expendable mode initially, to maximize delivered surface payload on each mission. The increased payload is

  13. External Beam Radiotherapy Plus 24-Hour Continuous Infusion of Gemcitabine in Unresectable Pancreatic Carcinoma: Long-Term Results of a Phase II Study

    SciTech Connect

    Mattiucci, Gian C.; Morganti, Alessio G.; Valentini, Vincenzo; Ippolito, Edy; Alfieri, Sergio; Antinori, Armando; Crucitti, Antonio; D'Agostino, Giuseppe R.; Di Lullo, Liberato; Luzi, Stefano; Mantini, Giovanna; Smaniotto, Daniela; Doglietto, Gian B.; Cellini, Numa

    2010-03-01

    Purpose: To evaluate the efficacy of gemcitabine-based chemoradiation (CT-RT) in treating patients (pts) affected by locally advanced pancreatic cancers (LAPC). Methods and Materials: Weekly gemcitabine (100 mg/m{sup 2}) was given as a 24-hour infusion during the course of three-dimensional radiotherapy (50.4 Gy to the tumor, 39.6 Gy to the nodes). After CT-RT, pts received five cycles of sequential chemotherapy with gemcitabine (1000 mg/m{sup 2}; 1, 8, q21). Response rate was assessed according to World Health Organization criteria 6 weeks after the end of CT-RT. Local control (LC), time to progression (TTP), metastases-free survival (MFS), and overall survival (OS) were analyzed by the Kaplan Meier method. Results: Forty pts (male/female 22/18; median age 62 years, range, 36-76) were treated from 2000 to 2005. The majority had T4 tumour (n = 34, 85%), six pts (15%) had T3 tumour. Sixteen pts (40%) were node positive at diagnosis. Grade 3-4 acute toxicity was observed in 21 pts (52.5%). Thirty pts (75%) completed the treatment schedule. A clinical response was achieved in 12 pts (30%). With a median follow-up of 76 months (range, 32-98), 2-year LC was 39.6% (median, 12 months), 2-year TTP was 18.4% (median, 10 months), and 2-year MFS was 29.7% (median, 10 months). Two-year OS (25%; median, 15.5 months) compared with our previous study on 5-fluorouracil-based CT-RT (2.8%) was significantly improved (p <0.001). Conclusions: Gemcitabine CT-RT seems correlated with improved outcomes. Healthier patients who are likely to complete the treatment schedule may benefit most from this therapy.

  14. Effects of ranitidine and cisapride on acid reflux and oesophageal motility in patients with reflux oesophagitis: a 24 hour ambulatory combined pH and manometry study.

    PubMed

    Inauen, W; Emde, C; Weber, B; Armstrong, D; Bettschen, H U; Huber, T; Scheurer, U; Blum, A L; Halter, F; Merki, H S

    1993-08-01

    The effect of ranitidine and cisapride on acid reflux and oesophageal motility was investigated in 18 patients with endoscopically verified erosive reflux oesophagitis. Each patient was treated with placebo, ranitidine (150 mg twice daily), and ranitidine (150 mg twice daily) plus cisapride (20 mg twice daily) in a double blind, double dummy, within subject, three way cross over design. Oesophageal acidity and motility were monitored under ambulatory conditions for 24 hours on the fourth day of treatment, after a wash out period of 10 days during which patients received only antacids for relief of symptoms. Acid reflux was monitored by a pH electrode located 5 cm above the lower oesophageal sphincter. Intraoesophageal pressure was simultaneously recorded from four transducers placed 20, 15, 10, and 5 cm above the lower oesophageal sphincter. Upright reflux was three times higher than supine reflux (median (range) 13.3 (3.7-35.0)% v 3.7 (0-37.6)% of the time with pH < 4.0, p < 0.01, n = 18). Compared with placebo, ranitidine decreased total reflux (from 10.0 (3.2-32.6)% to 6.4 (1.2-22.9)%, p < 0.01), upright reflux (p < 0.05), supine reflux (p < 0.001), and postprandial reflux (p < 0.01), but did not affect oesophageal motility. The combination of ranitidine with cisapride further diminished the acid reflux found with ranitidine--that is, cisapride led to an additional reduction of total reflux (from 6.4 (1.2-22.9)% to 3.7 (1.0-12.7)%, p < 0.01), supine reflux (p < 0.05), and postprandial reflux (p < 0.05). Cisapride also reduced both the number (p<0.01) and duration (p<0.05) of reflux episodes and significantly increased amplitude, duration, and propagation velocity of oesophageal contractions (p<0.05) but did not affect the number of contractions. The findings show that the 30% reduction of oesophageal acid exposure achieved by a conventional dose of ranitidine (150 mg twice daily) can be improved to more than 60% by combination with cisapride (20 mg twice daily

  15. Sex and age-related differences in performance in a 24-hour ultra-cycling draft-legal event – a cross-sectional data analysis

    PubMed Central

    2014-01-01

    Background The purpose of this study was to examine the sex and age-related differences in performance in a draft-legal ultra-cycling event. Methods Age-related changes in performance across years were investigated in the 24-hour draft-legal cycling event held in Schötz, Switzerland, between 2000 and 2011 using multi-level regression analyses including age, repeated participation and environmental temperatures as co-variables. Results For all finishers, the age of peak cycling performance decreased significantly (β = −0.273, p = 0.036) from 38 ± 10 to 35 ± 6 years in females but remained unchanged (β = −0.035, p = 0.906) at 41.0 ± 10.3 years in males. For the annual fastest females and males, the age of peak cycling performance remained unchanged at 37.3 ± 8.5 and 38.3 ± 5.4 years, respectively. For all female and male finishers, males improved significantly (β = 7.010, p = 0.006) the cycling distance from 497.8 ± 219.6 km to 546.7 ± 205.0 km whereas females (β = −0.085, p = 0.987) showed an unchanged performance of 593.7 ± 132.3 km. The mean cycling distance achieved by the male winners of 960.5 ± 51.9 km was significantly (p < 0.001) greater than the distance covered by the female winners with 769.7 ± 65.7 km but was not different between the sexes (p > 0.05). The sex difference in performance for the annual winners of 19.7 ± 7.8% remained unchanged across years (p > 0.05). The achieved cycling distance decreased in a curvilinear manner with advancing age. There was a significant age effect (F = 28.4, p < 0.0001) for cycling performance where the fastest cyclists were in age group 35–39 years. Conclusion In this 24-h cycling draft-legal event, performance in females remained unchanged while their age of peak cycling performance decreased and performance in males improved while their age of peak cycling performance remained unchanged. The annual fastest females and males were 37.3 ± 8.5 and 38.3 ± 5.4 years old, respectively. The sex

  16. Introduction to systolic algorithms and architectures

    SciTech Connect

    Bentley, J.L.; Kung, H.T.

    1983-01-01

    The authors survey the class of systolic special-purpose computer architectures and algorithms, which are particularly well-suited for implementation in very large scale integrated circuitry (VLSI). They give a brief introduction to systolic arrays for a reader with a broad technical background and some experience in using a computer, but who is not necessarily a computer scientist. In addition they briefly survey the technological advances in VLSI that led to the development of systolic algorithms and architectures. 38 references.

  17. When an Increase in Central Systolic Pressure Overrides the Benefits of Heart Rate Lowering.

    PubMed

    Messerli, Franz H; Rimoldi, Stefano F; Bangalore, Sripal; Bavishi, Chirag; Laurent, Stephane

    2016-08-16

    An elevated resting heart rate has been unequivocally linked to adverse cardiovascular events. Conversely, a physiologically low heart rate may confer longevity benefits. Moreover, pharmacological heart rate lowering reduces cardiovascular outcomes in patients with heart failure, with the magnitude of the reduction associated with survival benefit. In contrast, pharmacological heart rate lowering paradoxically increases cardiovascular events in hypertension, possibly because it elicits a ventricular-vascular mismatch, leading to increased central systolic blood pressure (BP). By the same hemodynamic mechanism, pharmacological heart rate lowering also engenders an increase in central (aortic) BP in coronary heart disease and, as a consequence, fails to decrease myocardial oxygen consumption. Whether in heart failure, hypertension, or coronary heart disease, or even athletes, heart rate lowering consistently increases central systolic pressure. The increase in central systolic BP is prone to abolish the potential benefits of heart rate lowering interventions, possibly accounting for failure to reduce outcomes in patients with hypertension and coronary artery disease. PMID:27515336

  18. Separate estimation of long- and short-term systolic blood pressure variability from photoplethysmograph.

    PubMed

    Kondo, Riho; Bhuiyan, Md Shoaib; Kawanaka, Haruki; Oguri, Koji

    2014-01-01

    This paper proposed a method to monitor systolic blood pressure (BP) variability without using a cuff during the daytime. In this method, BP variability of long-term and short-term were separated and estimated respectively from features of phoplethysmograph (PPG) through the use of a frequency filter. Then, total variability was obtained from the combination of long-term and short-term. BP by using a cuff (ground truth) and PPG of nine healthy young subjects were measured during the daytime; then BP variability was estimated from PPG to verify the validity of our method. As a result, the correlation coefficients between measured BP variability and estimated BP variability was improved from r = 0.35 in previous method to r = 0.41 in proposed method. In particular, the estimation results in short-term BP variability showed good accuracy (r = 0.67). This method of estimating BP variability has the potential to be a simple and continuous BP monitoring system during the daytime. PMID:25570338

  19. SLAPP: A systolic linear algebra parallel processor

    SciTech Connect

    Drake, B.L.; Luk, F.T.; Speiser, J.M.; Symanski, J.J.

    1987-07-01

    Systolic array computer architectures provide a means for fast computation of the linear algebra algorithms that form the building blocks of many signal-processing algorithms, facilitating their real-time computation. For applications to signal processing, the systolic array operates on matrices, an inherently parallel view of the data, using numerical linear algebra algorithms that have been suitably parallelized to efficiently utilize the available hardware. This article describes work currently underway at the Naval Ocean Systems Center, San Diego, California, to build a two-dimensional systolic array, SLAPP, demonstrating efficient and modular parallelization of key matric computations for real-time signal- and image-processing problems.

  20. Matrix computations on systolic-type meshes

    SciTech Connect

    Moreno, J.H.; Lang, T. )

    1990-04-01

    This article focuses on the execution of matrix computations on systolic-type arrays in an application-specific environment. The authors first present an extension to the concept of a systolic cell by incorporating a small, fixed amount of storage inside the cells, and they discuss the trade-offs this storage gives rise to. Then they review different approaches to decomposing (partitioning) large problems, highlighting their bandwidth requirements and their capabilities for using the storage in the cells. Finally, the authors discuss the basic characteristics of methods for the design of systolic-type arrays, describe the multimesh graph (MMG) design method, and illustrate its application to the transitive closure algorithm.

  1. Systolic temporal arithmetic: A new formalism for specification, verification, and synthesis of systolic arrays

    SciTech Connect

    Ling, N.

    1989-01-01

    A novel formalism, termed Systolic Temporal Arithmetic (STA), is introduced. It provides necessary constructs to describe arithmetic operations in dynamic environments. The motivation behind the development of STA is to use it for systolic array design at the array architecture level. It is particularly useful for formally specifying systolic array designs, and for formally verifying their correctness with respect to the algorithm specifications. Besides providing value and operation abstractions from the lower level, the formalism exploits unique systolic features such as synchrony, regularity, repeatability, modularity, pipelinability, parallel processing ability, as well as spatial and temporal locality, to provide constructs and verification techniques for simple, efficient, and effective systolic array specification verification. STA overcomes many limitations of current specification and verification techniques. It can be used with lower level formalism for multilevel reasoning of systolic arrays. Application examples are given to show how STA can be applied to specify and verify several different systolic arrays. To present a more unified design environment, STA is also extended to describe systolic array synthesis process. A synthesis procedure for systolic arrays is presented which also includes an algorithm transformation technique developed that can improve the computation time of resulting arrays for suitable algorithms, without much increase in area requirement. Several systolic array synthesis examples are also provided in this dissertation.

  2. Some results concerning linear iterative (systolic) arrays

    SciTech Connect

    Ibarra, O.H.; Palis, M.A.; Kim, S.M.

    1985-05-01

    The authors have shown some new interesting results concerning the properties, power, and limitations of various types of linear iterative (systolic) arrays. The method they employed consisted of finding sequential machine characterizations of these array models, and then using the characterizations to prove the results. Because of the absence of any concurrency and synchronization problems, the authors obtained simple proofs to results which when proved directly on the arrays would seem very difficult. The characterizations, therefore, provide a novel and promising method which can be used to analyze other systolic systems. In the future they hope to extend this methodology to the study of two-dimensional and multidimensional systolic arrays, and other systolic systems with different interconnection networks.

  3. Systolic arrays - From concept to implementation

    SciTech Connect

    Fortes, J.A.B.; Wah, B.W.

    1987-07-01

    Systolic arrays are the result of advances in semiconductor technology and of applications that require extensive throughput. Their realization requires human ingenuity combined with techniques and tools for algorithm development, architecture design, and hardware implementation. Invariably, the first reaction of people who are exposed to the systolic-array concept is one of admiration for the concept's elegance and for its potential for high performance. However, those who next attempt to implement a systolic array for a specific application soon realize that a wealth of subsumed concepts and engineering solutions must be mastered and understood. This special issue attempts to provide insights into the implementation process and to illustrate the different techniques and theories that contribute to the design of systolic arrays.

  4. Implementation and use of systolic array processes

    SciTech Connect

    Kung, H.T.

    1983-01-01

    Major effort are now underway to use systolic array processors in large, real-life applications. The author examines various implementation issues and alternatives, the latter from the viewpoints of flexibility and interconnection topologies. He then identifies some work that is essential to the eventual wide use of systolic array processors, such as the development of building blocks, system support and suitable algorithms. 24 references.

  5. Restructuring for fault-tolerant systolic arrays

    SciTech Connect

    Li, H.F.; Jayakumar, R.; Lam, C.

    1989-02-01

    The problem of restructuring systolic arrays with faulty cells is considered. An approach to derive the required data flow paths and computational sites is proposed. The data skewing requirement, which must be satisfied to find an input schedule, is also discussed. Algorithms to restructure systolic arrays for three different architecture of the processing elements are presented. A systematic method to retime the restructure array using additional programmable delays so that the retimed array satisfies the data skewing requirement is developed.

  6. Systolic acousto-optic binary convolver

    SciTech Connect

    Guilfoyle, P.S.

    1984-01-01

    A novel high speed array processing optical architecture is described. A multichannel acousto-optic binary convolver is architecturally configured as a systolic array processor. The architecture provides a high speed means of matrix/vector multiplications using the digital multiplication via an analog convolution algorithm. This algorithm and a systolic acousto-optic implementation permit the speed of optics to be combined with the accuracy of digital computation. 15 references.

  7. Baseline characteristics of African Americans in the Systolic Blood Pressure Intervention Trial.

    PubMed

    Still, Carolyn H; Craven, Timothy E; Freedman, Barry I; Van Buren, Peter N; Sink, Kaycee M; Killeen, Anthony A; Bates, Jeffrey T; Bee, Alberta; Contreras, Gabriel; Oparil, Suzanne; Pedley, Carolyn M; Wall, Barry M; White, Suzanne; Woods, Delia M; Rodriguez, Carlos J; Wright, Jackson T

    2015-09-01

    The Systolic Blood Pressure Intervention Trial (SPRINT) will compare treatment to a systolic blood pressure goal of <120 mm Hg to treatment to the currently recommended goal of <140 mm Hg for effects on incident cardiovascular, renal, and neurologic outcomes including cognitive decline. The objectives of this analysis are to compare baseline characteristics of African American (AA) and non-AA SPRINT participants and explore factors associated with uncontrolled blood pressure (BP) by race. SPRINT enrolled 9361 hypertensive participants aged older than 50 years. This cross-sectional analysis examines sociodemographics, baseline characteristics, and study measures among AAs compared with non-AAs. AAs made up 31% of participants. AAs (compared with non-AAs) were younger and less frequently male, had less education, and were more likely uninsured or covered by Medicaid. In addition, AAs scored lower on the cognitive screening test when compared with non-AAs. Multivariate logistic regression analysis found BP control rates to <140/90 mm Hg were higher for AAs who were male, had higher number of chronic diseases, were on diuretic treatment, and had better medication adherence. SPRINT is well poised to examine the effects of systolic blood pressure targets on clinical outcomes as well as predictors influencing BP control in AAs. PMID:26320890

  8. Design and descriptive tools for systolic architectures

    SciTech Connect

    Lewis, P.S.

    1984-01-01

    Automated design and descriptive tools are essential for the practical application of highly parallel special-purpose hardware such as systolic arrays. The use of special-purpose hardware can greatly increase the capabilities of signal processing systems. However, the more limited applications base makes design costs a critical factor in determining technical and economic viability. Systolic systems can be described at several levels of abstraction, each of which has unique descriptive requirements. This paper focuses on the descriptive issues involved at the system architectural level. Tools at this level must bridge the gap between logic- and circuit-oriented computer-aided design tools and algorithmic descriptions of systolic architectures. Traditionally, hardware description languages (HDLs) have been used at this level to describe conventional computer architectures. Systolic architectures, however, have different requirements. This paper examines these requirements and develops a set of criteria for evaluating HDLs. Four popular HDLs are evaluated and their strengths and weaknesses noted. The final section of the paper summarizes ongoing efforts at Los Alamos to develop a systolic array HDL based on the CONLAN family of languages.

  9. Design and descriptive tools for systolic architectures

    SciTech Connect

    Lewis, P.S.

    1984-01-01

    Automated design and descriptive tools are essential for the practical application of highly parallel special-purpose hardware such as systolic arrays. The use of special-purpose hardware can greatly increase the capabilities of signal processing systems. However, the more limited applications base makes design costs a critical factor in determining technical and economic viability. Systolic systems can be described at several levels of abstraction, each of which has unique descriptive requirements. This paper focuses on the descriptive issues involved at the system architectural level. Tools at this level must bridge the gap between logic- and circuit-oriented computer-aided design tools and algorithmic descriptions of systolic architectures. Traditionally, hardware description languages (HDLs) have been used at this level to describe conventional computer architectures. Systolic architectures, however, have different requirements. This paper examines these requirements and develops a set of criteria for evaluating HDLs. Four popular DHLs are evaluated and their strengths and weaknesses noted. The final section of the paper summarizes ongoing efforts at Los Alamos to develop a systolic array HDL based on the CONLAN family of languages. 14 references.

  10. Programming environments for systolic arrays. Technical report

    SciTech Connect

    Snyder, L.

    1986-02-01

    Although a systolic array is often thought of as a hard-wired device, there are many reasons to want to program systolic algorithms. In this paper the problem of providing an efficacious programming environment is addressed. The difficulties of programming complex parallel algorithms are shown to be reduced by using a new concept of a parallel program which maximizes the use of graphical abstractions and minimizes the need for symbolic text. This concept is illustrated by the Poker Parallel Programming Environment which, although designed for a broader class of algorithms, illustrates the main features that a programming environment specialized to systolic computation should have. In the event that the programming environment is for systolic arrays, the programs are parallel and thus impose additional demands on the system such as data formatting, management of multiple process sets, and the specification of data routings. Providing all of these facilities in a single integrated system requires a new concept of parallel program, which, although it is quite different from FORTRAN and PASCAL, is nevertheless easier to use for a systolic array than a conventional programming language. The key to achieving this simplicity is to use graphics so extensively that the resulting programs appear to be dynamic versions of the diagrams presented in textbooks.

  11. Systolic temporal arithmetic; A new formalism for specification and verification of systolic arrays

    SciTech Connect

    Ling, N. ); Bayoumi, M.A. )

    1990-08-01

    This paper introduces a novel formalism named systolic temporal arithmetic (STA) suitable for describing arithmetic operations in dynamic environments. The motivation behind the development of STA is to use it for formal specifications and verifications of systolic arrays at the array architecture level. Besides providing value and operation abstraction from the lower level, it also exploits several features of systolic arrays such as synchrony, regularity, repeatability, modularity, pipelinability, parallel processing ability, as well as spatial and temporal locality. STA provides constructs and verification techniques for simple, efficient, and effective systolic array specification and verification. Verification techniques such as mathematical induction are suggested to exploit these systolic array features so as to speedup the process.

  12. On mapping systolic algorithms onto the hypercube

    SciTech Connect

    Ibarra, O.H.; Sohn, S.M. )

    1990-01-01

    Much effort has been devoted toward developing efficient algorithms for systolic arrays. Here the authors consider the problem of mapping these algorithms into efficient algorithms for a fixed-size hypercube architecture. They describe in detail several optimal implementations of algorithms given for one-way one and two-dimensional systolic arrays. Since interprocessor communication is many times slower than local computation in parallel computers built to date, the problem of efficient communication is specifically addressed for these mappings. In order to experimentally validate the technique, five systolic algorithms were mapped in various ways onto a 64-node NCUBE/7 MMD hypercube machine. The algorithms are for the following problems: the shuffle scheduling problem, finite impulse response filtering, linear context-free language recognition, matrix multiplication, and computing the Boolean transitive closure. Experimental evidence indicates that good performance is obtained for the mappings.

  13. Algorithms for systolic-array synthesis

    SciTech Connect

    Wong, Yiwan.

    1989-01-01

    This dissertation presents efficient algorithms for solving some crucial transformation/optimization problems in the automatic synthesis of systolic arrays from algorithm specifications. The synthesis process consists of two steps. First, the given algorithm specification is transformed into a functionally equivalent form more amenable to systolic array implementation. Then, the computations defined by the equivalent form are assigned for execution on the processors (processor allocation) at different time steps (scheduling), with the objective that the time and space costs of the implementation be minimized. Many computation intensive algorithms, when expressed in their natural form, are unsuitable for systolic array implementations because they contain many-to-one data dependences (data sharing) which cannot be directly realized on processors with bounded fan-out and localized interconnections. A data routing scheme, called data propagation, is proposed which can be implemented as pipelining on a systolic array. It is shown that any data sharing can be transformed into data propagation and that the increase in I/O bandwidth requirement due to such transformation is bounded. Polynomial time procedures are devised for determining the necessary transformations. The time cost of a systolic array implementation of an algorithm is given by the product of two related quantities: the total number of systolic cycles required and the maximum duration of a cycle. It is shown that the scheduling which minimizes the time cost can be determined from solving a discrete optimization problem. Furthermore, the optimization problem is shown to have a bounded solution space, an efficient branch-and-bound method is proposed for determining the optimal solution. The space cost, on the other hand, is defined as the number of processors required for constructing the array.

  14. Sodium nitroprusside: low price and safe drug to control BP during thrombolysis in AIS.

    PubMed

    Koslyk, Jessyca L; Ducci, Renata D; Nóvak, Edison M; Zétola, Viviane F; Lange, Marcos C

    2015-09-01

    This study analyzes the use of sodium nitroprusside (SN) as an option to reduce blood pressure (BP) below 180/105 mmHg during the management of acute ischemic stroke (AIS) in patients submitted to intravenous thrombolysis.Method The sample was composed by 60 patients who had AIS and were submitted to intravenous rtPA, split in two groups: half in the control group (CG) with BP < 180/105 mmHg and half in SN group with BP > 180/105 mmHg. Outcome variables were any hemorrhagic transformation (HT); the presence of symptomatic HT, National Institute of Health Stroke Scale (NIHSS) after 24 hours of treatment; the independence on discharge and death until three months after stroke onset.Results There were no statistical differences between both groups to any of the outcome variables analyzed.Conclusion The SN might be safe for BP control during thrombolysis to AIS. PMID:26352493

  15. Investigation of cattle methane production and emission over a 24-hour period using measurements of δ13C and δD of emitted CH4 and rumen water

    NASA Astrophysics Data System (ADS)

    Bilek, R. S.; Tyler, S. C.; Kurihara, M.; Yagi, K.

    2001-07-01

    We have conducted a series of experiments to determine the effects different diets, including the addition of unsaturated fatty acids, had on isotopic signatures of CH4 emissions from dairy cattle. Measurements of emitted δ13CH4, δ13CO2, and δD-CH4 were made on gases collected over a 24-hour period from animal chambers containing individual Holstein cows. Some measurements of δD-H2O from samples collected directly from the rumen were also made. We observed variation in δ13CH4 values with time after feeding and a correlation in δ13C between emitted gases and diet. The average δ13CH4 value, which includes all samples of emitted gases, was -70.6±4.9‰ (n = 57). Measurements of δD-CH4 over the 24-hour sampling period had an average value of -357.8±15.0‰ (n = 56). These δD measurements are among the lightest reported for CH4 produced by cattle. Our cattle data indicate that hydrogen incorporated into the CH4 produced by CO2 reduction in high H2 concentration environments is fractionated to a greater degree than that incorporated in systems with relatively low H2 conditions, such as wetlands. Our results support bacterial studies that have demonstrated large hydrogen fractionation in high H2 concentration systems during methanogenesis.

  16. Synthesis, verification, and optimization of systolic arrays

    SciTech Connect

    Rajopadhye, S.V.

    1986-01-01

    This dissertation addresses the issue of providing a sound theoretical basis for three important issues relating to systolic arrays, namely synthesis, verification, and optimization. Former research has concentrated on analysis of the dependency structure of the computation, and there have been numerous approaches to map this dependency structure onto a locally interconnected network. This study pursues a similar approach, but with a major generalization of the class of problems analyzed. In earlier research, it was essential that the dependencies were expressible as constant vectors (from a point in the domain to the points that it depended on); here they are permitted to be arbitrary linear functions of the point. Theory for synthesizing systolic architectures from such generalized specifications is developed. Also a systematic (mechanizable) approach to the synthesis of systolic architectures that have control signals is presented. In the areas of verification and optimization, a rigorous mathematical framework is presented that permits reasoning about the behavior of systolic arrays as functions on streams of data. Using this approach, the verification of such architectures reduces to the problem of verification of functional program.s

  17. A unified systolic array for adaptive beamforming

    SciTech Connect

    Bojanczyk, A.W.; Luk, F.T. )

    1990-04-01

    The authors present a new algorithm and systolic array for adaptive beamforming. The authors algorithm uses only orthogonal transformations and thus should have better numerical properties. The algorithm can be implemented on one single p {times} p triangular array of programmable processors that offers a throughput of one residual element per cycle.

  18. 24-hour urinary aldosterone excretion rate

    MedlinePlus

    ... RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods . 22nd ed. Philadelphia, PA: Elsevier Saunders; ... by: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University ...

  19. Toys Remain Viral Playground for 24 Hours

    MedlinePlus

    ... a toy's surface at typical indoor temperatures and humidity levels. Specifically, they tested the ability of so- ... East Respiratory Syndrome (MERS). At 60 percent relative humidity, 1 percent of the virus remained infectious on ...

  20. Elevated BP after AKI.

    PubMed

    Hsu, Chi-Yuan; Hsu, Raymond K; Yang, Jingrong; Ordonez, Juan D; Zheng, Sijie; Go, Alan S

    2016-03-01

    The connection between AKI and BP elevation is unclear. We conducted a retrospective cohort study to evaluate whether AKI in the hospital is independently associated with BP elevation during the first 2 years after discharge among previously normotensive adults. We studied adult members of Kaiser Permanente Northern California, a large integrated health care delivery system, who were hospitalized between 2008 and 2011, had available preadmission serum creatinine and BP measures, and were not known to be hypertensive or have BP>140/90 mmHg. Among 43,611 eligible patients, 2451 experienced AKI defined using observed changes in serum creatinine concentration measured during hospitalization. Survivors of AKI were more likely than those without AKI to have elevated BP-defined as documented BP>140/90 mmHg measured during an ambulatory, nonemergency department visit-during follow-up (46.1% versus 41.2% at 730 days; P<0.001). This difference was evident within the first 180 days (30.6% versus 23.1%; P<0.001). In multivariable models, AKI was independently associated with a 22% (95% confidence interval, 12% to 33%) increase in the odds of developing elevated BP during follow-up, with higher adjusted odds with more severe AKI. Results were similar in sensitivity analyses when elevated BP was defined as having at least two BP readings of >140/90 mmHg or those with evidence of CKD were excluded. We conclude that AKI is an independent risk factor for subsequent development of elevated BP. Preventing AKI during a hospitalization may have clinical and public health benefits beyond the immediate hospitalization. PMID:26134154

  1. Cross-Sectional Study of 24-Hour Urinary Electrolyte Excretion and Associated Health Outcomes in a Convenience Sample of Australian Primary Schoolchildren: The Salt and Other Nutrients in Children (SONIC) Study Protocol

    PubMed Central

    Baxter, Janet R; Campbell, Karen J; Riddell, Lynn J; Rigo, Manuela; Liem, Djin Gie; Keast, Russell S; He, Feng J; Nowson, Caryl A

    2015-01-01

    Background Dietary sodium and potassium are involved in the pathogenesis of cardiovascular disease. Data exploring the cardiovascular outcomes associated with these electrolytes within Australian children is sparse. Furthermore, an objective measure of sodium and potassium intake within this group is lacking. Objective The primary aim of the Salt and Other Nutrient Intakes in Children (“SONIC”) study was to measure sodium and potassium intakes in a sample of primary schoolchildren located in Victoria, Australia, using 24-hour urine collections. Secondary aims were to identify the dietary sources of sodium and potassium, examine the association between these electrolytes and cardiovascular risk factors, and assess children’s taste preferences and saltiness perception of manufactured foods. Methods A cross-sectional study was conducted in a convenience sample of schoolchildren attending primary schools in Victoria, Australia. Participants completed one 24-hour urine collection, which was analyzed for sodium, potassium, and creatinine. Completeness of collections was assessed using collection time, total volume, and urinary creatinine. One 24-hour dietary recall was completed to assess dietary intake. Other data collected included blood pressure, body weight, height, waist and hip circumference. Children were also presented with high and low sodium variants of food products and asked to discriminate salt level and choose their preferred variant. Parents provided demographic information and information on use of discretionary salt. Descriptive statistics will be used to describe sodium and potassium intakes. Linear and logistic regression models with clustered robust standard errors will be used to assess the association between electrolyte intake and health outcomes (blood pressure and body mass index/BMI z-score and waist circumference) and to assess differences in taste preference and discrimination between high and low sodium foods, and correlations between

  2. Bidiagonalization and symmetric tridiagonalization by systolic arrays

    NASA Technical Reports Server (NTRS)

    Schreiber, Robert

    1988-01-01

    A systolic algorithm and an array for bidiagonalization of an nxn matrix in O(nlog(2)n) time, using O(n to the 2nd power) cells are given. Bandedness of the input matrix may be effectively exploited. If the matrix is banded, with p nonzero subdiagonals and q nonzero superdiagonals, then 4nln(p + q) + O(n) clocks and 2n(p + q) + O((p + q) to the 2nd power + n) cells are needed. This is faster than the best previously reported result by the factor log(2)e = 1.44.... Moreover, in contrast to earlier systolic designs, which require the matrix to be preloaded into the array and the result matrix extracted after bidiagonalization, the present arrays are pipelined.

  3. Hardware description languages for systolic architectures

    SciTech Connect

    Lewis, P.S.

    1984-10-01

    Systolic principles can be used to construct special purpose computer systems that achieve high throughput by exploiting algorithmic properties. These principles of regularity, localized communications, and parallel/pipelined execution nicely match the capabilities of integrated circuit technology. Hence, systolic arrays are an attractive method for building high-speed special-purpose hardware to rapidly solve sophisticated problems. However, the use of special-purpose hardware limits the applications base, making fixed costs such as those associated with system design much more critical. Although design costs are in part reduced by the very nature of systolic systems, further reduction can result from the use of automated design and descriptive tools. The design process stretches from the conception of the algorithm and its mapping onto an architecture down to the electronic implementation. In general, a good set of design tools allows the designer to describe, test, and trade off only those factors that are important at that particular point in the design process. A principle requirement in automating the design process is a formal notational mechanism that is capable of providing complete and unambiguous descriptions of the concepts being explored. This notational mechanism then provides a common basis for comparisons between alternate methods and an input mechanism to automated design tools. This thesis identifies the notational features that are necessary for the description of highly parallel, regular architectures such as systolic arrays. A set of language criteria is developed. A number of the more popular HDLs are evaluated using these criteria and their shortcomings noted. 65 references.

  4. Optical systolic array processor using residue arithmetic

    NASA Technical Reports Server (NTRS)

    Jackson, J.; Casasent, D.

    1983-01-01

    The use of residue arithmetic to increase the accuracy and reduce the dynamic range requirements of optical matrix-vector processors is evaluated. It is determined that matrix-vector operations and iterative algorithms can be performed totally in residue notation. A new parallel residue quantizer circuit is developed which significantly improves the performance of the systolic array feedback processor. Results are presented of a computer simulation of this system used to solve a set of three simultaneous equations.

  5. Systolic Time Intervals and New Measurement Methods.

    PubMed

    Tavakolian, Kouhyar

    2016-06-01

    Systolic time intervals have been used to detect and quantify the directional changes of left ventricular function. New methods of recording these cardiac timings, which are less cumbersome, have been recently developed and this has created a renewed interest and novel applications for these cardiac timings. This manuscript reviews these new methods and addresses the potential for the application of these cardiac timings for the diagnosis and prognosis of different cardiac diseases. PMID:27048269

  6. Tomographic image reconstruction using systolic array algorithms

    SciTech Connect

    Azevedo, S.G.; DeGroot, A.J.; Schneberk, D.J.; Brase, J.M.; Martz, H.E.; Jain, A.K.; Current, K.W.; Hurst, P.J.

    1988-12-22

    Image reconstruction for Computed Tomography (CT) is a time consuming operation on current uniprocessor computers and even on array processors. This is particularly true for three-dimensional data sets or for limited-data reconstructions requiring iterative procedures. In these cases, the projection operation (Radon transform) and its inverse (filtered back-projection) are major computational tasks that are performed many times. Multiprocessor computers, especially in systolic array configurations, can provide dramatic improvements in reconstruction times at reasonable costs. An in-house systolic processor, called SPRINT, has been programmed to demonstrate these improved speeds while achieving near 100% efficiency of all processor elements. We report on these results in this paper. In addition, two proposed hardware implementations of a new architecture are shown to have even greater speedup possibilities. One, using standard DSP chips, has been simulated to give a factor of three improvement over SPRINT, while the other, using custom VLSI that is now in the early stages of design, could potentially perform 512/sup 2/ reconstructions at video rates (100 times further speedup). These processors are also interconnected in a systolic array configuration. Experimental and projected results, with future plans, are also reported in this paper. 11 refs., 5 figs., 1 tab.

  7. Systolic blood pressure and systolic hypertension in adolescence of atomic bomb survivors exposed in utero.

    PubMed

    Nakashima, Eiji; Akahoshi, Masazumi; Neriishi, Kazuo; Fujiwara, Saeko

    2007-11-01

    Annual medical examinations were conducted during adolescence for the in utero clinical study sample subjects exposed prenatally to the atomic bombs in Hiroshima and Nagasaki. Systolic blood pressure and several anthropometric measurements were recorded during these examinations. For 1014 persons exposed in utero, two types of longitudinal analyses were performed, for a total of 7029 observations (6.93 observations per subject) of systolic blood pressure (continuous data) and systolic hypertension (binary data) for persons aged 9 to 19 years. Body mass index (BMI) and/or body weight were considered in the analyses as potential confounders. For the measurements of systolic blood pressure, the common dose effect was 2.09 mmHg per Gy and was significant (P = 0.017). The dose by trimester interaction was suggestive (P = 0.060). A significant radiation dose effect was found in the second trimester (P = 0.001), with an estimated 4.17 mmHg per Gy, but in the first and third trimesters, radiation dose effects were not significant (P > 0.50). For prevalence of systolic hypertension, the radiation dose effect was significant (P = 0.009); the odds ratio at 1 Gy was 2.23 [95% confidence interval (CI): 1.23, 4.04], and the dose by trimester interaction was not significant (P = 0.778). The dose response of systolic hypertension had no dose threshold, with a threshold point estimate of 0 Gy (95% CI: <0.0, 1.1 Gy). The dose response for systolic blood pressure was most pronounced in the second trimester, the most active organogenesis period for the organs relevant to blood pressure. PMID:17973553

  8. A chair for cuffless real-time estimation of systolic blood pressure based on pulse transit time.

    PubMed

    Tang, Zunyi; Sekine, Masaki; Tamura, Toshiyo; Yoshida, Masaki; Chen, Wenxi

    2015-01-01

    This study presents an unobtrusive cuffless blood pressure (BP) monitoring system for estimating beat-by-beat systolic blood pressure (SBP) in real-time based on pulse transit time (PTT). The system mainly includes an electrocardiograph with three conductive textile electrodes, a pulse monitor with a LED and a photodetector, a control circuit with a Bluetooth module, and a battery, all of which are mounted on a common armchair to measure ECG and photoplethysmography (PPG) signals from users during sitting on the armchair. The measured ECG and PPG data are transmitted to the software terminal installed on a tablet PC and are further derived to obtain a series of PTT for estimating beat-by-beat BP using Chen's method. We had 9 healthy subjects undergo the BP monitoring experiments of still sitting on a chair for 3 minutes, lying on a bed for 10 minutes, and pedaling using ergometer for 11 minutes in order to assess the accuracy of the estimated BP. A Finometer and a cuff-type BP meter were used as references in the experiments. Preliminary results showed that the mean error and mean absolute difference (MAD) of estimated BP were within -0.5 ± 5.3 mmHg and 4.1 ± 3.4 mmHg, respectively, compared to references. The result suggests that the proposed BP estimation system has the potential for long-term home BP monitoring. PMID:26737443

  9. Adaptive identification by systolic arrays. Master's thesis

    SciTech Connect

    Willis, P.A.

    1987-12-01

    This thesis is concerned with the implementation of an adaptive-identification algorithm using parallel processing and systolic arrays. In particular, discrete samples of input and output data of a system with uncertain characteristics are used to determine the parameters of its model. The identification algorithm is based on recursive least squares, QR decomposition, and block-processing techniques with covariance resetting. Along similar lines as previous approaches, the identification process is based on the use of Givens rotations. This approach uses the Cordic algorithm for improved numerical efficiency in performing the rotations. Additionally, floating-point and fixed-point arithmetic implementations are compared.

  10. Systolic hypertension: an increasing clinical challenge in Asia

    PubMed Central

    Park, Jeong Bae; Kario, Kazuomi; Wang, Ji-Guang

    2015-01-01

    Systolic hypertension, the predominant form of hypertension in patients aged over 50–60 years, is a growing health issue as the Asian population ages. Elevated systolic blood pressure is mainly caused by arterial stiffening, resulting from age-related vascular changes. Elevated systolic pressure increases the risk of cardiovascular disease, mortality and renal function decline, and this risk may increase at lower systolic pressure levels in Asian than Western subjects. Hence, effective systolic pressure lowering is particularly important in Asians yet blood pressure control remains inadequate despite the availability of numerous antihypertensive medications. Reasons for poor blood pressure control include low awareness of hypertension among health-care professionals and patients, under-treatment, and tolerability problems with antihypertensive drugs. Current antihypertensive treatments also lack effects on the underlying vascular pathology of systolic hypertension, so novel drugs that address the pathophysiology of arterial stiffening are needed for optimal management of systolic hypertension and its cardiovascular complications. PMID:25503845

  11. Isolated Systolic Hypertension in Young and Middle-Aged Adults and 31-Year Risk for Cardiovascular Mortality

    PubMed Central

    Yano, Yuichiro; Stamler, Jeremiah; Garside, Daniel B.; Daviglus, Martha L.; Franklin, Stanley S.; Carnethon, Mercedes R.; Liu, Kiang; Greenland, Philip; Lloyd-Jones, Donald M.

    2016-01-01

    BACKGROUND Isolated systolic hypertension (ISH), defined as systolic blood pressure (SBP) ≥140 mm Hg and diastolic blood pressure (DBP) <90 mm Hg, in younger and middle-aged adults is increasing in prevalence. OBJECTIVE The aim of this study was to assess the risk for cardiovascular disease (CVD) with ISH in younger and middle-aged adults. METHODS CVD risks were explored in 15,868 men and 11,213 women 18 to 49 years of age (mean age 34 years) at baseline, 85% non-Hispanic white, free of coronary heart disease (CHD) and antihypertensive therapy, from the Chicago Heart Association Detection Project in Industry study. Participant classifications were as follows: 1) optimal-normal blood pressure (BP) (SBP <130 mm Hg and DBP <85 mm Hg); 2) high-normal BP (130 to 139/85 to 89 mm Hg); 3) ISH; 4) isolated diastolic hypertension (SBP <140 mm Hg and DBP ≥90 mm Hg); and 5) systolic diastolic hypertension (SBP ≥140 mm Hg and DBP ≥90 mm Hg). RESULTS During a 31-year average follow-up period (842,600 person-years), there were 1,728 deaths from CVD, 1,168 from CHD, and 223 from stroke. Cox proportional hazards models were adjusted for age, race, education, body mass index, current smoking, total cholesterol, and diabetes. In men, with optimal-normal BP as the reference stratum, hazard ratios for CVD and CHD mortality risk for those with ISH were 1.23 (95% confidence interval [CI]: 1.03 to 1.46) and 1.28 (95% CI: 1.04 to 1.58), respectively. ISH risks were similar to those with high-normal BP and less than those associated with isolated diastolic hypertension and systolic diastolic hypertension. In women with ISH, hazard ratios for CVD and CHD mortality risk were 1.55 (95% CI: 1.18 to 2.05) and 2.12 (95% CI: 1.49 to 3.01), respectively. ISH risks were higher than in those with high-normal BP or isolated diastolic hypertension and less than those associated with systolic diastolic hypertension. CONCLUSIONS Over long-term follow-up, younger and middle-aged adults with ISH

  12. The Relationship of the Increase in the 'Time of the Earth Day,' from 18 Hours to 24 Hours, to the Increase in the Size of the Earth, Using the Laws of the Conservation of Momentum

    NASA Astrophysics Data System (ADS)

    Cimorelli, S. A.; Samuels, C.

    2010-12-01

    There are three articles, by others, which discuss the increase in the Earth's day, from 18 hours to 24 hours, over a period of time of about a billion years. One article refers to Striations in the Substructure of Coral, C.T. Scrutton, et al, 1965. Another article refers to the Laws of the Conservation of Momentum, as related to the relationship of the Earth and the Moon, the lunar tides, the reduction of the Earth year from 481 days to our present 365.25 days, and an increase in the lunar orbit time from 20 days to 28 days. The third article is based on the dates of tidal sediment deposits, tidalites, C. P. Sonett, et al, in the late 1980's. In this paper, we explain how the Earth's Day could have increased from 18 hours to 24 hours, as related to the Laws of Conservation of Momentum (L). Wherein we use the simple formulation from the Law of the Conservation of Angular Momentum, L=Iω, in which I=Moment of Inertia and ω=Angular Velocity; for which we assume the earth to be a perfect sphere, for which I=0.4MR2, where M and R are the Mass and radius of the earth, respectively. We evaluate the radius of the earth over a time period of several billion years, during which time the earth's angular momentum, L=Iω, is conserved. In this formulation, we show a growth in the size of the earth; and present a curve, using just three points in time, which indicates that the rate of growth is increasing over time. The first point is from about 4.5 billion years ago, the second point is from about 1 billion years ago, and the third point represents present day, with an average growth of about 1mm per year. Although evidence has been presented, by others, showing circumferential growth at the Red Sea and in the Atlantic Ocean, at about 1.5cm per year, total. However, no proof of reduction in the size of the Earth has been shown to occur in the Pacific, or anywhere else, including in references to subduction. Some might say that the subduction is occurring at the rim of the

  13. Effects of aliskiren- and ramipril-based treatment on central aortic blood pressure in elderly with systolic hypertension: a substudy of AGELESS

    PubMed Central

    Baschiera, Fabio; Chang, William; Brunel, Patrick

    2014-01-01

    Background Systolic hypertension is the most common form of hypertension in elderly patients. There is increasing evidence that measurement of central aortic pressure (CAP) better accounts for cardiovascular risk than brachial blood pressure (BP). The Aliskiren for GEriatric LowEring of SyStolic hypertension (AGELESS) study in elderly patients with systolic hypertension showed that aliskiren-based therapy provided greater reductions in peripheral BP than ramipril-based therapy over 12 and 36 weeks of treatment. Here, we present CAP results in a substudy of elderly patients from the AGELESS study. Methods This was a post hoc analysis of a 36-week, randomized, double-blind, parallel-group, active-controlled, optional-titration study in patients ≥65 years of age with systolic BP ≥140 mmHg. Changes in both central and peripheral BP and pulse pressure (PP) and changes in systolic and PP amplification ratios from baseline to the week 36 end point with aliskiren-based versus ramipril-based therapy were analyzed. Results Of the 901 patients randomized in the overall study, 154 patients (aliskiren, n=78; ramipril, n=76) had CAP data. Numerically comparable reductions were seen for central aortic systolic pressure (CASP) in aliskiren-based therapy (baseline: 143.7±15.0; week 36: −20.3±16.2) compared with ramipril-based therapy (baseline: 147.9±11.9; week 36: −20.7±14.6). However, for the change in central aortic diastolic pressure, the least squares mean between-treatment difference (−3.6 mmHg [95% confidence interval, −6.76, −0.43; P=0.0263]) was in favor of aliskiren, while the other changes were comparable between the two groups with a trend in favor of aliskiren for CASP as well (−2.6 mmHg [95% confidence interval, −7.38, 2.19; P=0.2855)]. Correlation coefficients for change from baseline between CASP and systolic BP and between central aortic pulse pressure and PP (r=0.8, P<0.0001) were highly significant. Conclusion Aliskiren-based therapy

  14. The Preoperative Patient With a Systolic Murmur

    PubMed Central

    Cowie, Brian

    2015-01-01

    Context: Patients with undifferentiated systolic murmurs present commonly during the perioperative period. Traditional bedside assessment and auscultation has not changed significantly in almost 200 years and relies on interpreting indirect acoustic events as a means of evaluating underlying cardiac pathology. This is notoriously inaccurate, even in expert cardiology hands, since many different valvular and cardiac diseases present with a similar auditory signal. Evidence Acquisition: The data on systolic murmurs, physical examination, perioperative valvular disease in the setting of non-cardiac surgery is reviewed. Results: Significant valvular heart disease increases perioperative risk in major non-cardiac surgery and increases long term patient morbidity and mortality. We propose a more modern approach to physical examination that incorporates the use of focused echocardiography to allow direct visualization of cardiac structure and function. This improves the diagnostic accuracy of clinical assessment, allows rational planning of surgery and anaesthesia technique, risk stratification, postoperative monitoring and appropriate referral to physicians and cardiologists. Conclusions: With a thorough preoperative assessment incorporating focused echocardiography, anaesthetists are in the unique position to enhance their role as perioperative physicians and influence short and long term outcomes of their patients. PMID:26705529

  15. 78 FR 60270 - BP America Inc., BP Corporation North America Inc., BP America Production Company, and BP Energy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission BP America Inc., BP Corporation North America Inc., BP America Production Company, and BP Energy Company; Notice of Designation of Commission Staff as Non-Decisional With...

  16. Very high central aortic systolic pressures in a young hypertensive patient on telmisartan: Is central aortic systolic pressure associated with white coat hypertension?

    PubMed

    Sule, Ashish Anil; Hwang, Teong Hui; Chin, Tay Jam

    2010-01-01

    Central aortic systolic pressure (CASP) is a very well-recognized tool to assess the end organ damage in patients with hypertension. It is known that angiotensin-converting enzyme inhibitors, angiotensin receptor blockers and calcium channel blockers reduce CASP more than some antihypertensives such as beta-blockers. White coat hypertension with CASP has not been described and validated. The present report describes a very anxious 24-year-old patient on telmisartan (an angiotensin receptor blocker), with a very high CASP compared with his peripheral blood pressure (BP). He had a strong family history of hypertension, and was fairly well controlled on 80 mg/day telmisartan, with his BP ranging from 125/80 mmHg to 130/85 mmHg (home BP monitoring). In May 2009, he underwent routine CASP at Tan Tock Seng Hospital (Singapore), and ambulatory BP measurements using a BPro watch (HealthSTATS, Singapore). The patient had a CASP of 132 mmHg at the hospital, but his calculated CASP by ambulatory BP measurement at 1 pm was 120 mmHg. His ambulatory BPs were 137/94 mmHg; thus, hydrochlorothiazide was added for further control. He was advised to repeat CASP measurements on follow-up in six weeks. He followed up on June 18, 2009, and July 30, 2009, and his CASPs were 139 mmHg and 137 mmHg, respectively. He underwent a magnetic resonance aortogram to exclude any obstructive cause for very high CASPs. His magnetic resonance aortogram revealed no evidence of coarctation of the aorta. CASP may have significant variations due to white coat phenomenon. Further 24 h CASP studies are needed to observe whether CASP is subject to white coat phenomenon. PMID:22479144

  17. Effective cross-over to granisetron after failure to ondansetron, a randomized double blind study in patients failing ondansetron plus dexamethasone during the first 24 hours following highly emetogenic chemotherapy

    PubMed Central

    de Wit, R; de Boer, A C; vd Linden, G H M; Stoter, G; Sparreboom, A; Verweij, J

    2001-01-01

    In view of the similarity in chemical structure of the available 5HT3-receptor antagonists it is assumed, whilst these agents all act at the same receptor, that failure to one agent would predict subsequent failure to all 5HT3-receptor antagonists. We conducted a randomized double blind trial of granisetron 3 mg plus dexamethasone 10 mg versus continued treatment with ondansetron 8 mg plus dexamethasone 10 mg in patients with protection failure on ondansetron 8 mg plus dexamethasone 10 mg during the first 24 hours following highly emetogenic chemotherapy. Of 40 eligible patients, 21 received ondansetron + dexamethasone and 19 received granisetron + dexamethasone. We found a significant benefit from crossing-over to granisetron after failure on ondansetron. Of the 19 patients who crossed over to granisetron, 9 patients obtained complete protection, whereas this was observed in 1 of the 21 patients continuing ondansetron, P = 0.005. These results indicate that there is no complete cross-resistance between 5HT3-receptor antagonists, and that patients who have acute protection failure on one 5HT3-receptor antagonist should be offered cross-over to another 5HT3-receptor antagonist. © 2001 Cancer Research Campaign  http://www.bjcancer.com PMID:11710819

  18. Management of Patients With Recovered Systolic Function.

    PubMed

    Basuray, Anupam; Fang, James C

    2016-01-01

    Advancements in the treatment of heart failure (HF) with systolic dysfunction have given rise to a new population of patients with improved ejection fraction (EF). The management of this distinct population is not well described due to a lack of consensus on the definition of myocardial recovery, a scarcity of data on the natural history of these patients, and the absence of focused clinical trials. Moreover, an improvement in EF may have different prognostic and management implications depending on the underlying etiology of cardiomyopathy. This can be challenging for the clinician who is approached by a patient inquiring about a reduction of medical therapy after apparent EF recovery. This review explores management strategies for HF patients with recovered EF in a disease-specific format. PMID:26796969

  19. Optical systolic solutions of linear algebraic equations

    NASA Technical Reports Server (NTRS)

    Neuman, C. P.; Casasent, D.

    1984-01-01

    The philosophy and data encoding possible in systolic array optical processor (SAOP) were reviewed. The multitude of linear algebraic operations achievable on this architecture is examined. These operations include such linear algebraic algorithms as: matrix-decomposition, direct and indirect solutions, implicit and explicit methods for partial differential equations, eigenvalue and eigenvector calculations, and singular value decomposition. This architecture can be utilized to realize general techniques for solving matrix linear and nonlinear algebraic equations, least mean square error solutions, FIR filters, and nested-loop algorithms for control engineering applications. The data flow and pipelining of operations, design of parallel algorithms and flexible architectures, application of these architectures to computationally intensive physical problems, error source modeling of optical processors, and matching of the computational needs of practical engineering problems to the capabilities of optical processors are emphasized.

  20. Singular value decomposition with systolic arrays

    NASA Technical Reports Server (NTRS)

    Ipsen, I. C. F.

    1984-01-01

    Systolic arrays for determining the singular value decomposition of a mxn, m n, matrix A of bandwidth w are presented. After A has been reduced to bidiagonal form B by means of Givens plane rotations, the singular values of B are computed by the Golub-Reinsch iteration. The products of plane rotations form the matrices of left and right singular vectors. Assuming each processor can compute or supply a plane rotation, O(wn) processors accomplish the reduction to bidiagonal form in O(np) steps, where p is the number of superdiagonals. A constant number of processors then determines each singular value in about 6n steps. The singular vectors are computed by rerouting the rotations through the arrays used for the reduction to bidiagonal form, or else along the way by employing another rectangular array of O(wm) processors.

  1. Using redundancy for testable and repairable systolic arrays

    SciTech Connect

    Shombert, L.A.

    1985-01-01

    This thesis presents a method of using spares to enhance the reliability and testability of systolic arrays. The method, called roving spares, provides fault detection and fault isolation without interrupting array operation, essentially providing a self testing array. Systolic arrays are defined, and the design space of systolic arrays is identified. The methodology for roving spares on the simplest, but still very powerful, type of systolic array is then derived. Several detailed designs are generated to provide sample data points for analysis. The analysis shows that reliability is increased by factors of two to ten, over a nonredundant array, and that this improvement is achieved at low cost. The testing capability of roving spares does not significantly decrease the reliability benefits of spares. A brief analysis of a more complex systolic array indicates that the benefits achievable for the simple array can be expected for all types of systolic arrays.

  2. Disrupting the EMMPRIN-Cyclophilin A interaction reduces infarct size and preserves systolic function after myocardial ischemia and reperfusion

    PubMed Central

    Seizer, Peter; Ochmann, Carmen; Schönberger, Tanja; Zach, Sebastian; Rose, Melanie; Borst, Oliver; Klingel, Karin; Kandolf, Reinhard; MacDonald, H. Robson; Nowak, Romana A.; Engelhardt, Stefan; Lang, Florian; Gawaz, Meinrad; May, Andreas E.

    2011-01-01

    Introduction Inflammation and proteolysis crucially contribute to myocardial ischemia and reperfusion injury. The Extracellular Matrix Metalloproteinase Inducer (EMMPRIN, CD147) and its ligand Cyclophilin A (CyPA) may be involved in both processes. The aim of the study was to characterize the role of the CD147 and CyPA interplay in myocardial ischemia/reperfusion (I/R) injury. Methods and results Immunohistochemistry showed enhanced expression of CD147 and CyPA in myocardial sections from human autopsies of patients who had died from acute myocardial infarction and from mice at 24 hours after I/R. At 24 hours and 7 days after I/R, the infarct size was reduced in CD147+/− mice versus CD147+/+ mice (C57Bl/6), in mice (C57Bl/6) treated with mAb anti-CD147 vs. control mAb, and in CyPA−/− mice vs. CyPA+/+ mice (129S6/SvEv), all of which being associated with reduced monocyte and neutrophil recruitment at 24h and with a preserved systolic function at 7 days. Combination of CyPA−/− mice with anti-CD147 treatment did not yield further protection in comparison to either inhibition strategy alone. In vitro, treatment with CyPA induced monocyte chemotaxis in a CD147- and PI3-kinase dependent manner and induced monocyte rolling and adhesion to endothelium (HUVEC) under flow in a CD147-dependent manner. Conclusion CD147 and its ligand CyPA are inflammatory mediators after myocardial ischemia and reperfusion and represent potential targets to prevent myocardial I/R injury. PMID:21441138

  3. Blood pressure (BP) assessment-from BP level to BP variability.

    PubMed

    Feber, Janusz; Litwin, Mieczyslaw

    2016-07-01

    The assessment of blood pressure (BP) can be challenging in children, especially in very young individuals, due to their variable body size and lack of cooperation. In the absence of data relating BP with cardiovascular outcomes in children, there is a need to convert absolute BP values (in mmHg) into age-, gender- and height appropriate BP percentiles or Z-scores in order to compare a patient's BP with the BP of healthy children of the same age, but also of children of different ages. Traditionally, the interpretation of BP has been based mainly on the assessment of the BP level obtained by office, home or 24-h BP monitoring. Recent studies suggest that it is not only BP level (i.e. average BP) but also BP variability that is clinically important for the development of target organ damage, including the progression of chronic kidney disease. In this review we describe current methods to evaluate of BP level, outline available methods for BP variability assessment and discuss the clinical consequences of BP variability, including its potential role in the management of hypertension. PMID:26201477

  4. Recursive least squares estimation and Kalman filtering by systolic arrays

    NASA Technical Reports Server (NTRS)

    Chen, M. J.; Yao, K.

    1988-01-01

    One of the most promising new directions for high-throughput-rate problems is that based on systolic arrays. In this paper, using the matrix-decomposition approach, a systolic Kalman filter is formulated as a modified square-root information filter consisting of a whitening filter followed by a simple least-squares operation based on the systolic QR algorithm. By proper skewing of the input data, a fully pipelined time and measurement update systolic Kalman filter can be achieved with O(n squared) processing cells, resulting in a system throughput rate of O (n).

  5. Comparison of validity of food group intake by food frequency questionnaire between pre- and post- adjustment estimates derived from 2-day 24-hour recalls in combination with the probability of consumption.

    PubMed

    Kim, Dong Woo; Oh, Se-Young; Kwon, Sung-Ok; Kim, Jeongseon

    2012-01-01

    Validation of a food frequency questionnaire (FFQ) utilising a short-term measurement method is challenging when the reference method does not accurately reflect the usual food intake. In addition, food group intake that is not consumed on daily basis is more critical when episodically consumed foods are related and compared. To overcome these challenges, several statistical approaches have been developed to determine usual food intake distributions. The Multiple Source Method (MSM) can calculate the usual food intake by combining the frequency questions of an FFQ with the short-term food intake amount data. In this study, we applied the MSM to estimate the usual food group intake and evaluate the validity of an FFQ with a group of 333 Korean children (aged 3-6 y) who completed two 24-hour recalls (24HR) and one FFQ in 2010. After adjusting the data using the MSM procedure, the true rate of non-consumption for all food groups was less than 1% except for the beans group. The median Spearman correlation coefficients against FFQ of the mean of 2-d 24HRs data and the MSM-adjusted data were 0.20 (range: 0.11 to 0.40) and 0.35 (range: 0.14 to 0.60), respectively. The weighted kappa values against FFQ ranged from 0.08 to 0.25 for the mean of 2-d 24HRs data and from 0.10 to 0.41 for the MSM-adjusted data. For most food groups, the MSM-adjusted data showed relatively stronger correlations against FFQ than raw 2-d 24HRs data, from 0.03 (beverages) to 0.34 (mushrooms). The results of this study indicated that the application of the MSM, which was a better estimate of the usual intake, could be worth considering in FFQ validation studies among Korean children. PMID:22938437

  6. L-NAME raises systolic blood pressure in the pithed rat by a direct adrenal epinephrine releasing action.

    PubMed

    Elayan, Hamzeh H; Kennedy, Brian P; Ziegler, Michael G

    2002-04-21

    It is generally thought that inhibition of nitric oxide synthase leads to blood pressure elevation largely through reduction in vascular levels of the vasodilator nitric oxide. However, there are several reports suggesting that NO synthase inhibitors cause adrenal epinephrine (E) release by both central and peripheral mechanisms. We investigated the role of adrenal E in the pressor effects of the nitric oxide synthase inhibitor L-NAME in the pithed rat to help distinguish central from peripherally mediated actions. L-NAME (10 mg/kg) raised both systolic and diastolic BP by about 30 mm Hg (P < .01) in the absence of exogenous electrical stimulation of sympathetic nerves. During stimulation at 10 V and frequencies of 1 or 2 Hz, systolic BP was about 70 mm Hg higher in L-NAME treated rats than in drug free stimulated rats. This enhancement of systolic BP by L-NAME was less pronounced at 5 or 10 Hz stimulation frequencies. Following these types of electrical stimulations of pithed rats, both plasma norepinephrine (NE) and E levels were dramatically elevated above resting plasma levels. L-NAME pretreatment of these electrically stimulated rats increased plasma E levels by an additional 60% and decreased NE by 18%. Acute adrenalectomy dramatically reduced plasma E levels and abolished the ability of L-NAME to enhance the pressor effect of sympathetic stimulation. In contrast, acute adrenalectomy of unstimulated pithed rats did not significantly reduce the pressor response to L-NAME. We conclude that adrenal E release may mediate much of the systolic pressor response of L-NAME in the stimulated pithed rat, but the magnitude of this effect varies with stimulation frequency. Since pithing disrupts central pathways, this induction of adrenal E release by L-NAME is a peripheral effect. PMID:12173412

  7. Nesfatin-1 and Vitamin D levels may be associated with systolic and diastolic blood pressure values and hearth rate in polycystic ovary syndrome.

    PubMed

    Sahin, Figen Kir; Sahin, Serap Baydur; Ural, Ulku Mete; Cure, Medine Cumhur; Senturk, Senol; Tekin, Yesim Bayoglu; Balik, Gulsah; Cure, Erkan; Yuce, Suleyman; Kirbas, Aynur

    2015-01-01

    Obesity, insulin resistance (IR), inflammation, and hyperandrogenism may lead to polycystic ovary syndrome (PCOS) and hypertension. Nesfatin-1 (N1) may be related to IR, obesity, and hypertension. Furthermore, a vitamin D (VD) deficiency is associated with hypertension and PCOS. We aimed to investigate N1 and VD levels in PCOS that have an effect on systolic and diastolic blood pressure (BP) and heart rate (HR).This study included 54 patients with PCOS and 48 age-body mass index (BMI)-matched healthy controls. PCOS was diagnosed according to clinical practice guidelines. Ferriman-Gallwey scores (FGS) were calculated, while N1, VD, and other hormonal and biochemical parameters were measured for all subjects. Systolic and diastolic BP was measured as well. HR was calculated using an electrocardiogram.The levels of N1 (p < 0.001), high-sensitivity C-reactive protein (hs-CRP) (p = 0.036), homeostasis model assessment as an index of insulin resistance (HOMA-IR) (p < 0.001), systolic (p < 0.001) and diastolic (p < 0.001) BP and HR (p < 0.001) in the PCOS group were significantly higher than in the control group. However, the VD levels of the PCOS group were lower than the control group (p = 0.004). N1 had a strong positive correlation with BMI, HOMA-IR, hs-CRP, luteinizing hormone, systolic and diastolic BP, and HR. VD levels were negatively correlated with HOMA-IR and luteinizing hormone.Elevated N1 and decreased VD levels may be related to the presence of high-normal BP or hypertension in PCOS subjects.  N1 level may be associated with an increased BP due to its relation to inflammation and IR. PMID:26295295

  8. Nesfatin-1 and Vitamin D levels may be associated with systolic and diastolic blood pressure values and hearth rate in polycystic ovary syndrome

    PubMed Central

    Sahin, Figen Kir; Sahin, Serap Baydur; Ural, Ulku Mete; Cure, Medine Cumhur; Senturk, Senol; Tekin, Yesim Bayoglu; Balik, Gulsah; Cure, Erkan; Yuce, Suleyman; Kirbas, Aynur

    2015-01-01

    Obesity, insulin resistance (IR), inflammation, and hyperandrogenism may lead to polycystic ovary syndrome (PCOS) and hypertension. Nesfatin-1 (N1) may be related to IR, obesity, and hypertension. Furthermore, a vitamin D (VD) deficiency is associated with hypertension and PCOS. We aimed to investigate N1 and VD levels in PCOS that have an effect on systolic and diastolic blood pressure (BP) and heart rate (HR). This study included 54 patients with PCOS and 48 age-body mass index (BMI)-matched healthy controls. PCOS was diagnosed according to clinical practice guidelines. Ferriman-Gallwey scores (FGS) were calculated, while N1, VD, and other hormonal and biochemical parameters were measured for all subjects. Systolic and diastolic BP was measured as well. HR was calculated using an electrocardiogram. The levels of N1 (p < 0.001), high-sensitivity C-reactive protein (hs-CRP) (p = 0.036), homeostasis model assessment as an index of insulin resistance (HOMA-IR) (p < 0.001), systolic (p < 0.001) and diastolic (p < 0.001) BP and HR (p < 0.001) in the PCOS group were significantly higher than in the control group. However, the VD levels of the PCOS group were lower than the control group (p = 0.004). N1 had a strong positive correlation with BMI, HOMA-IR, hs-CRP, luteinizing hormone, systolic and diastolic BP, and HR. VD levels were negatively correlated with HOMA-IR and luteinizing hormone. Elevated N1 and decreased VD levels may be related to the presence of high-normal BP or hypertension in PCOS subjects. N1 level may be associated with an increased BP due to its relation to inflammation and IR. PMID:26295295

  9. Design of easily testable and reconfigurable systolic arrays

    SciTech Connect

    Kim, J.H.

    1987-01-01

    Systolic arrays are considered to be preferred architectures for executing linear algebraic operations. In this thesis, easily testable and reconfigurable (ETAR) systolic arrays are studied to achieve the yield enhancement. New 2-D systolic arrays that lend themselves to easy reconfiguration as well as efficient implementations of algorithms are proposed. The 2-D bidirectional and unidirectional systolic arrays proposed are often better architectures than the rectangular and hexagonal systolic arrays proposed earlier, if one considers area, time and reconfigurability. Methods to design linear and 2-D ETAR systolic arrays are proposed. Procedures to design linear and 2-D unidirectional and bidirectional systolic arrays are given. The main feature of the proposed designs is that the COMUs of the PEs in the linear array can all be tested simultaneously. Another feature is that the throughputs of the reconfigured linear unidirectional as well as bidirectional arrays can remain to be equal to those of the fault-free linear arrays. A reconfiguration algorithm for 2-D systolic arrays is also proposed.

  10. Systoles on Heisenberg groups with Carnot-Caratheodory metrics

    SciTech Connect

    Dontsov, V V

    2001-04-30

    The systolic properties of the nilmanifolds N{sup 2n+1} associated with the higher Heisenberg groups H{sub 2n+1} are studied. Effective estimates of the systolic constants {sigma}(N{sup 2n+1}) in the Carnot-Caratheodory geometry, as functions of the parameters defining a uniform lattice on H{sub 2n+1}, are obtained.

  11. Efficacy of a classical antiobesity Unani pharmacopial formulation (Safoof-e-Muhazzil) in systolic and diastolic blood pressure: A randomized, open-labeled, controlled clinical study

    PubMed Central

    Khan, Asim Ali; Jahangir, Umar; Jalees, Farhan; Kapoor, Prem; Urooj, Shaista

    2013-01-01

    The aim of this study is to evaluate the efficacy of a Unani formulation in hypertension. A total of 90 patients with total cholesterol level of more than 220 mg/dl with associated conditions were included in this study. A total of 30 patients having a mean systolic blood pressure (BP) of 133.86 mmHg comprising Group A received Unani formulation Safoof-e-Muhazzil (SM) in its classical powder form in the dose of 5 g twice a day orally. Group B comprising of 30 patients with a mean systolic BP of 133.13 mmHg received same drug, but in compressed tablet form in the same dosage, whereas, 30 patients comprising Group C with a mean systolic BP of 129.45 mmHg, received Atorvastatin 10 mg as a standard control. Patients were evaluated on each follow-up at 2nd, 4th and 6th week. The mean systolic BP in Group A and B before treatment was 133.86 ± 3.028 mmHg and 133.13 ± 2.852 mmHg, which significantly decreased to 119.33 ± 1.922 mmHg (P < 0.001) and 119 ± 1.760 mmHg (P < 0.001) respectively. In the control Group C before treatment BP was 129.45 ± 2.499 mmHg and after treatment it significantly decreased to 124.34 ± 1.794 mmHg (P < 0.01). The percentage change after treatment was 10.85%, 10.61% and 3.94% respectively in each group. Mean diastolic BP in Group A and B before treatment was 85.06 ± 2.11 mmHg and 84.56 ± 1.5 mmHg, which significantly decreased to 79.06 ± 1.56 mmHg (P < 0.001) and 79.96 ± 1.15 mmHg (P < 0.001) respectively, BP before treatment in Group C was 83.23 ± 1.588 mmHg, which was decreased to 124.34 ± 1.794 mmHg (P < 0.01). The study results indicate that the test drug was quite effective in reducing both systolic as well as diastolic BP. PMID:24350049

  12. The otolaryngologic manifestations of gastroesophageal reflux disease (GERD): a clinical investigation of 225 patients using ambulatory 24-hour pH monitoring and an experimental investigation of the role of acid and pepsin in the development of laryngeal injury.

    PubMed

    Koufman, J A

    1991-04-01

    Occult (silent) gastroesophageal reflux disease (GER, GERD) is believed to be an important etiologic factor in the development of many inflammatory and neoplastic disorders of the upper aerodigestive tract. In order ot test this hypothesis, a human study and an animal study were performed. The human study consisted primarily of applying a new diagnostic technique (double-probe pH monitoring) to a population of otolaryngology patients with GERD to determine the incidence of overt and occult GERD. The animal study consisted of experiments to evaluate the potential damaging effects of intermittent GER on the larynx. Two hundred twenty-five consecutive patients with otolaryngologic disorders having suspected GERD evaluated from 1985 through 1988 are reported. Ambulatory 24-hour intraesophageal pH monitoring was performed in 197; of those, 81% underwent double-probe pH monitoring, with the second pH probe being placed in the hypopharynx at the laryngeal inlet. Seventy percent of the patients also underwent barium esophagography with videofluoroscopy. The patient population was divided into seven diagnostic subgroups: carcinoma of the larynx (n = 31), laryngeal and tracheal stenosis (n = 33), reflux laryngitis (n = 61), globus pharyngeus (n = 27), dysphagia (n = 25), chronic cough (n = 30), and a group with miscellaneous disorders (n = 18). The most common symptoms were hoarseness (71%), cough (51%), globus (47%), and throat clearing (42%). Only 43% of the patients had gastrointestinal symptoms (heartburn or acid regurgitation). Thus, by traditional symptomatology, GER was occult or silent in the majority of the study population. Twenty-eight patients (12%) refused or could not tolerate pH monitoring. Of the patients undergoing diagnostic pH monitoring, 62% had abnormal esophageal pH studies, and 30% demonstrated reflux into the pharynx. The results of diagnostic pH monitoring for each of the subgroups were as follows (percentage with abnormal studies): carcinoma (71

  13. Systolic array IC for genetic computation

    NASA Technical Reports Server (NTRS)

    Anderson, D.

    1991-01-01

    Measuring similarities between large sequences of genetic information is a formidable task requiring enormous amounts of computer time. Geneticists claim that nearly two months of CRAY-2 time are required to run a single comparison of the known database against the new bases that will be found this year, and more than a CRAY-2 year for next year's genetic discoveries, and so on. The DNA IC, designed at HP-ICBD in cooperation with the California Institute of Technology and the Jet Propulsion Laboratory, is being implemented in order to move the task of genetic comparison onto workstations and personal computers, while vastly improving performance. The chip is a systolic (pumped) array comprised of 16 processors, control logic, and global RAM, totaling 400,000 FETS. At 12 MHz, each chip performs 2.7 billion 16 bit operations per second. Using 35 of these chips in series on one PC board (performing nearly 100 billion operations per second), a sequence of 560 bases can be compared against the eventual total genome of 3 billion bases, in minutes--on a personal computer. While the designed purpose of the DNA chip is for genetic research, other disciplines requiring similarity measurements between strings of 7 bit encoded data could make use of this chip as well. Cryptography and speech recognition are two examples. A mix of full custom design and standard cells, in CMOS34, were used to achieve these goals. Innovative test methods were developed to enhance controllability and observability in the array. This paper describes these techniques as well as the chip's functionality. This chip was designed in the 1989-90 timeframe.

  14. Blood Pressure, Left Ventricular Geometry, and Systolic Function in Children Exposed to Inorganic Arsenic

    PubMed Central

    Osorio-Yáñez, Citlalli; Ayllon-Vergara, Julio C.; Arreola-Mendoza, Laura; Aguilar-Madrid, Guadalupe; Hernández-Castellanos, Erika; Sánchez-Peña, Luz C.

    2015-01-01

    Background: Inorganic arsenic (iAs) is a ubiquitous element present in the groundwater worldwide. Cardiovascular effects related to iAs exposure have been studied extensively in adult populations. Few epidemiological studies have been focused on iAs exposure–related cardiovascular disease in children. Objective: In this study we investigated the association between iAs exposure, blood pressure (BP), and functional and anatomical echocardiographic parameters in children. Methods: A cross-sectional study of 161 children between 3 and 8 years was conducted in Central Mexico. The total concentration of arsenic (As) species in urine (U-tAs) was determined by hydride generation–cryotrapping–atomic absorption spectrometry and lifetime iAs exposure was estimated by multiplying As concentrations measured in drinking water by the duration of water consumption in years (LAsE). BP was measured by standard protocols, and M-mode echocardiographic parameters were determined by ultrasonography. Results: U-tAs concentration and LAsE were significantly associated with diastolic (DBP) and systolic blood pressure (SBP) in multivariable linear regression models: DBP and SBP were 0.013 (95% CI: 0.002, 0.024) and 0.021 (95% CI: 0.004, 0.037) mmHg higher in association with each 1-ng/mL increase in U-tAs (p < 0.025), respectively. Left ventricular mass (LVM) was significantly associated with LAsE [5.5 g higher (95% CI: 0.65, 10.26) in children with LAsE > 620 compared with < 382 μg/L-year; p = 0.03] in an adjusted multivariable model. The systolic function parameters left ventricular ejection fraction (EF) and shortening fraction were 3.67% (95% CI: –7.14, –0.20) and 3.41% (95% CI: –6.44, –0.37) lower, respectively, in children with U-tAs > 70 ng/mL compared with < 35 ng/mL. Conclusion: Early-life exposure to iAs was significantly associated with higher BP and LVM and with lower EF in our study population of Mexican children. Citation: Osorio-Yáñez C, Ayllon-Vergara JC

  15. New methodology for systematic construction of systolic arrays

    SciTech Connect

    Faroughi, N.

    1987-01-01

    Transforming an algorithm, represented by mathematical expressions with uniform and bounded index spaces, into a systolic-array architecture is discussed. Systolic arrays are highly structured architectures tailored to a specific application. They have specific architectural properties such as simple processing elements (cells), simple and regular data and control communication, and local-cell interconnections. The new design method is based on an understanding of the relationship between two highly structured representations of the algorithms: the mathematical expressions and their systolic solutions. The method consists of three major steps: algorithm representation, algorithm model, and architecture specification. The algorithm representation involves the translation of mathematical expressions into a set of equivalent simple computations which are grouped into subsets based on the required set of operations and same type operands. In the algorithm model, the properties of systolic arrays are represented in terms of feature interrelationships. A sub-systolic array is designed separately for each subset of the simple computations. The final array is constructed by joining the sub-systolic arrays. Other architecture specifications, such as data movement and cell count ratio, are determined early in a design process and thus can be used to select systolic solutions that require fewest cells and lowest I/O bandwidth.

  16. Casein-Derived Lactotripeptides Reduce Systolic and Diastolic Blood Pressure in a Meta-Analysis of Randomised Clinical Trials

    PubMed Central

    Fekete, Ágnes A.; Givens, D. Ian; Lovegrove, Julie A.

    2015-01-01

    There is an urgent need to treat individuals with high blood pressure (BP) with effective dietary strategies. Previous studies suggest a small, but significant decrease in BP after lactotripeptides (LTP) ingestion, although the data are inconsistent. The study aim was to perform a comprehensive meta-analysis of data from all relevant randomised controlled trials (RCT). Medline, Cochrane library, EMBASE and Web of Science were searched until May 2014. Eligibility criteria were RCT that examined the effects of LTP on BP in adults, with systolic BP (SBP) and diastolic BP (DBP) as outcome measures. Thirty RCT met the inclusion criteria, which resulted in 33 sets of data. The pooled treatment effect for SBP was −2.95 mmHg (95% CI: −4.17, −1.73; p < 0.001), and for DBP was −1.51 mmHg (95% CI: −2.21, −0.80; p < 0.001). Sub-group analyses revealed that reduction of BP in Japanese studies was significantly greater, compared with European studies (p = 0.002 for SBP and p < 0.001 for DBP). The 24-h ambulatory BP (AMBP) response to LTP supplementation was statistically non-significant (p = 0.101 for SBP and p = 0.166 for DBP). Both publication bias and “small-study effect” were identified, which shifted the treatment effect towards less significant SBP and non-significant DBP reduction after LTP consumption. LTP may be effective in BP reduction, especially in Japanese individuals; however sub-group, meta-regression analyses and statistically significant publication biases suggest inconsistencies. PMID:25608938

  17. The application of systolic arrays to radar signal processing

    NASA Astrophysics Data System (ADS)

    Spearman, R.; Spracklen, C. T.; Miles, J. H.

    The design of a systolic array processor radar system is examined, and its performance is compared to that of a conventional radar processor. It is shown how systolic arrays can be used to replace the boards of high speed logic normally associated with a high performance radar and to implement all of the normal processing functions associated with such a system. Multifunctional systolic arrays are presented that have the flexibility associated with a general purpose digital processor but the speed associated with fixed function logic arrays.

  18. [The influence of citoflavin on molecular mechanisms of hypertensive encephalopathy development in patients with systolic arterial hypertension].

    PubMed

    Kartashova, E A; Romantsov, M G; Sarvilina, I V

    2014-01-01

    The molecular pharmacological effects of cytoflavin in patients with hypertensive encephalopathy (HE) and isolated systolic arterial hypertension (ISAH) have been investigated using the following methods: assessment of complaints, 24-hour arterial pressure monitoring, ultrasound diagnostics including echocardiography, measurement of lipid profiles and coagulograms, and molecular phenotyping by MALDI-TOF/TOF-MS. A combination of cytoflavin administration with standard therapy of HE and ISAH led to the most expressed return development of clinical symptoms, restoration of the hemodynamic, structural, and geometrical parameters of cardiovascular system, and normalization of the indices of lipid profiles and coagulograms in comparison to patients with HE and ISAH, which accepted only standard therapy. Molecular mechanisms of cytoflavin action have been revealed, which include control of the activity of cellular signaling pathways by means of intermolecular interactions. The optimized therapy of HE and ISAH is recommended for clinical application, which assumes a combined use of standard therapy and cytoflavin and provides a geroprotective action upon the cardiovascular system. PMID:25102730

  19. Proceedings of the international conference on systolic arrays

    SciTech Connect

    Not Available

    1988-01-01

    The proceedings of this conference are grouped under the following headings: signal processing algorithms; applications; matrix algorithms; applications; architecture; algorithms; mapping methodology; design methodologies and tools; fault-tolerance and testing; hardware implementation; implementation; bit-level systolic systems.

  20. Systematic designs of buffers in macropipelines of systolic arrays

    SciTech Connect

    Wah, B.W.; Aboelaze, M.; Shang, W.

    1988-02-01

    In a macropipeline of systolic arrays, outputs of one systolic array in a given format have to be fed as inputs to another systolic array in a possibly different format. A common memory becomes a bottleneck and limits the number of systolic arrays that can be connected together. In this paper, they study designs of buffers to convert data from one format to another. The minimum number of buffers is determined by a dynamic-programming algorithm with THETA(n/sup 2/) computational complexity, where n is the problem size. A general-purpose converter to convert data from any distribution to any other in a subset of the possible data distribution is also proposed. Last, buffer designs for a macropipeline to perform feature extraction and pattern classification are used to exemplify the design process.

  1. A class of SIMD machines simulated by systolic arrays

    SciTech Connect

    Umeo, H.

    1985-11-01

    In this paper the authors introduce a new subclass of single instruction steam/multiple data stream (SIMD) machines, referred to as a simple SIMD, then consider an implementation of a class of simple SIMD parallel algorithms onto systolic arrays, which have been considered as one candidate for VLSI-based cellular computers. The class of simple SIMD algorithms is so large that it includes many conventional SIMD algorithms, such as sorting, image processing, and graph algorithms. We develop several time-efficient algorithms for the simulations of simple SIMD machines, which have global data communications, by systolic arrays with only local data communications. The systolic simulation theorems enable us to use many conventional SIMD algorithms on the systolic arrays with little loss of time efficiency.

  2. Loewner's conjecture, the Besicovitch barrel, and relative systolic geometry

    SciTech Connect

    Babenko, I K

    2002-04-30

    The paper is devoted to relative systolic geometry on a compact manifold with boundary. Sufficient conditions ensuring the intersystolic rigidity or intersystolic softness of such manifolds are analyzed. Several open questions are formulated.

  3. Late systolic click in non-obstructive cardiomyopathy

    PubMed Central

    Mercer, Edward N.; Frye, Robert L.; Giuliani, Emilio R.

    1970-01-01

    Two patients with seriously impaired left ventricular function, abnormal left ventricular conduction on the electrocardiogram, mitral regurgitation, and a very late systolic click are reported. Idiopathic non-obstructive cardiomyopathy seemed to be the cause of the left ventricular dysfunction in both cases. The mitral valve was anatomically normal at the time of operation in one patient, except for dilatation of the annulus, and the mitral regurgitation appeared to be secondary to left ventricular failure. The very late timing of the mitral systolic clicks in these two patients may be related to a large left ventricular end-diastolic volume and impaired left ventricular function, or to an abnormal sequence of excitation of the left ventricle. The timing of the late systolic click in these patients is in contrast to that in patients with mid systolic clicks, hearts of normal size, and little cardiac disability. Images PMID:5470052

  4. Systolic s/sup 2/-way merge sort is optimal

    SciTech Connect

    Schmeck, H.; Schroder, H.; Starke, C.

    1989-07-01

    The time complexity of Thompson and Kun's s/sup 2/-way merge sort is analyzed and shown to be asymptotically optimal with respect to the recently improved lower bound on sorting on a mesh-connected n x n array. Furthermore, new lower bounds for systolic sorting are derived. A systolic version of s/sup 2/-way merge sort is systematically constructed and shown to be asymptotically optimal as well.

  5. A virtual zero-time, monolithic systolic sorting array

    SciTech Connect

    Britton, C.L.; Ericson, M.N.; Bouldin, D.W.

    1989-01-01

    A virtual zero-time monolithic sorting chip is described. The chip has a systolic array architecture and implements the ''sinking sort'' algorithm. The basic functional module of the systolic array is detailed and development techniques employed as well as functional simulation and results are presented. Lessons learned and educational significance of the development of this chip at a university are discussed. 3 refs., 4 figs.

  6. Minimum complexity FIR filters and sparse systolic arrays

    SciTech Connect

    Ferrari, L.A.; Sankar, P.V.

    1988-06-01

    The properties of BETA-spline approximation and the integral/derivative properties of convolution lead to efficient algorithms for the implementation of multidimensional FIR filters. The implementations are of minimum time complexity under the Nyquist criterion. The algorithm can easily be implemented using a sparse systolic array architecture. The resulting BETA-spline convolvers have much lower circuit complexity than systolic architectures based on conventional convolution algorithms. A two-dimensional hardware implementation based on simplifications of current architectures is presented.

  7. A virtual zero-time, monolithic systolic sorting array

    SciTech Connect

    Britton, C.L. Jr.; Ericson, M.N.; Bouldin, D.W.; Tennessee Univ., Knoxville, TN )

    1990-01-01

    A virtual zero-time monolithic sorting chip is described. The chip has a systolic array architecture and implements the sinking sort'' algorithm. The basic functional module of the systolic array is detailed and development techniques employed as well as functional simulation and results are presented. Lessons learned and educational significance of the development of this chip at a university are discussed. 3 refs., 4 figs.

  8. Vibration white finger and digital systolic pressure during cooling.

    PubMed Central

    Ekenvall, L; Lindblad, L E

    1986-01-01

    A cold provocation test (measurement of finger systolic pressure during combined body and local finger cooling) was performed on 111 male patients exposed to vibration and with a typical history of cold induced white finger. A new method of calculating the test result is described--namely, digital systolic blood pressure in the cooled test finger as a percentage of the systolic pressure in the arm (DP%). The conventional way of calculating the result, the systolic pressure in the cooled test finger as a percentage of the systolic pressure in the test finger when heated to 30 degrees C, corrected for changes in systemic pressure by the use of a reference finger (FSP%), requires the measurement of the systolic pressure in a reference finger. The two ways of calculating the test results give a similar sensitivity (74% for FSP%, 79% for DP% if all histories are regarded as true) but the new method does not require pressure measurements in a reference finger. This makes the test easier to perform and the result easier to understand. PMID:3964577

  9. Attenuation of systolic blood pressure and pulse transit time hysteresis during exercise and recovery in cardiovascular patients.

    PubMed

    Liu, Qing; Yan, Bryan P; Yu, Cheuk-Man; Zhang, Yuan-Ting; Poon, Carmen C Y

    2014-02-01

    Pulse transit time (PTT) is a cardiovascular parameter of emerging interest due to its potential to estimate blood pressure (BP) continuously and without a cuff. Both linear and nonlinear equations have been used in the estimation of BP based on PTT. This study, however, demonstrates that there is a hysteresis phenomenon between BP and PTT during and after dynamic exercise. A total of 46 subjects including 16 healthy subjects, 13 subjects with one or more cardiovascular risk factors, and 17 patients with cardiovascular disease underwent graded exercise stress test. PTT was measured from electrocardiogram and photoplethysmogram of the left index finger of the subject, i.e., a pathway that includes predominately aorta, brachial, and radial arteries. The results of this study showed that, for the same systolic BP (SBP), PTT measured during exercise was significantly larger than PTT measured during recovery for all subject groups. This hysteresis was further quantified as both normalized area bounded by the SBP-PTT relationship (AreaN) and SBP difference at PTT during peak exercise plus 20 ms (ΔSBP20). Significant attenuation of both AreaN (p <; 0.05) and ΔSBP20 (p <; 0.01) is observed in cardiovascular patients compared with healthy subjects, independent of resting BP. Since the SBP-PTT relationship are determined by the mechanical properties of arterial wall, which is predominately mediated by the sympathetic nervous system through altered vascular smooth muscle (VSM) tone during exercise, results of this study are consistent with the previous findings of autonomic nervous dysfunction in cardiovascular patients. We further conclude that VSM tone has a nonnegligible influence on the BP-PTT relationship and thus should be considered in the PTT-based BP estimation. PMID:24158470

  10. Arterial Wave Reflection and Subclinical Left Ventricular Systolic Dysfunction

    PubMed Central

    Russo, Cesare; Jin, Zhezhen; Takei, Yasuyoshi; Hasegawa, Takuya; Koshaka, Shun; Palmieri, Vittorio; Elkind, Mitchell S.V.; Homma, Shunichi; Sacco, Ralph L.; Di Tullio, Marco R.

    2011-01-01

    Objectives Increased arterial wave reflection is a predictor of cardiovascular events and has been hypothesized to be a cofactor in the pathophysiology of heart failure. Whether increased wave reflection is inversely associated with left ventricular (LV) systolic function in subjects without heart failure is not clear. Methods Arterial wave reflection and LV systolic function were assessed in 301 participants from the Cardiovascular Abnormalities and Brain Lesions (CABL) study using 2-dimensional echocardiography and applanation tonometry of the radial artery to derive central arterial waveform by a validated transfer function. Aortic augmentation index (AIx) and wasted energy index (WEi) were used as indices of wave reflection. LV systolic function was measured by ejection fraction (LVEF) and tissue Doppler imaging (TDI). Mitral annulus peak systolic velocity (Sm), peak longitudinal strain and strain rate were measured. Participants with history of coronary artery disease, atrial fibrillation, LVEF <50% or wall motion abnormalities were excluded. Results Mean age of the study population was 68.3±10.2 years (64.1% women, 65% hypertensive). LV systolic function by TDI was lower with increasing wave reflection, whereas LVEF was not. In multivariate analysis, TDI parameters of LV longitudinal systolic function were significantly and inversely correlated to AIx and WEi (p values from 0.05 to 0.002). Conclusions In a community cohort without heart failure and with normal LVEF, an increased arterial wave reflection was associated with subclinical reduction in LV systolic function assessed by novel TDI techniques. Further studies are needed to investigate the prognostic implications of this relationship. PMID:21169863

  11. Use of systolic pressure variation to predict the cardiovascular response to mini-fluid challenge in anaesthetised dogs.

    PubMed

    Rabozzi, R; Franci, P

    2014-11-01

    Systolic pressure variation (SPV), the maximum variation in systolic pressure values following a single positive pressure breath delivered by controlled mechanical ventilation (CMV), is highly correlated with volaemia in dogs. The aim of this study was to determine an SPV value that would indicate when fluid administration would be beneficial in clinical practice. Twenty-six client-owned dogs were anaesthetised, following which CMV with a peak inspiratory pressure (PIP) of 8 cmH2O was applied. After SPV measurement and recording of heart rate (HR) and blood pressure (BP), 3 mL/kg fluid were administered, then HR and BP were recorded again. Dogs exhibiting a 10% decrease in HR and/or an increase in BP were defined as responders, and their SPV pre-bolus was analysed retrospectively. SPV values > 4 mmHg or >4.5% predicted haemodynamic improvement in dogs with normal cardiovascular function, with a sensitivity of 90% and a specificity of 87%. The area under the curve receiver operating characteristic value for SPV was 0.931 mmHg (95% confidence interval, CI, 0.76-0.99 mmHg) and 0.944% (95% CI 0.78-0.99%). It is proposed that SPV values > 4.5% in dogs with a normal cardiovascular function, anaesthetised with isoflurane in oxygen and air, and on CMV (PIP 8 cmH2O), can be used to predict a cardiovascular response (>10% increase in mean arterial BP and/or >10% decrease in heart rate). PMID:25199508

  12. Mapping nested loop algorithms into multidimensional systolic arrays

    SciTech Connect

    Lee, P.Z. ); Kedem, Z.M. )

    1990-01-01

    This paper is concerned with transforming depth p-nested for loop algorithms into q-dimensional systolic VLSI arrays where 1 {le} q {le} p {minus} 1. Previously there existed complete characterizations of correct transformations only for the cases when q = p {minus} 1 or q = 1. The authors fill in this gap by giving formal necessary and sufficient conditions for correct transformation of a p-nested loop algorithm into a q-dimensional systolic array for any q, 1 {le} q {le} p {minus} 1. They also provide practical methods to derive optimal or suboptimal systolic array implementations. They apply the techniques developed by us to the automatic design of special purpose and programmable systolic arrays. The author's results also contribute towards automatic compilation onto more general purpose programmable arrays. Synthesis of linear and planar systolic array implementations for a three-dimensional cube-graph algorithm and a reindexed Warshall-Floyd pathfinding algorithm is used to illustrate our method.

  13. Heart Rate and Systolic Blood Pressure Variability on Recently Diagnosed Diabetics

    PubMed Central

    Michel-Chávez, Anaclara; Estañol, Bruno; Gien-López, José Antonio; Robles-Cabrera, Adriana; Huitrado-Duarte, María Elena; Moreno-Morales, René; Becerra-Luna, Brayans

    2015-01-01

    Background Diabetes affects approximately 250 million people in the world. Cardiovascular autonomic neuropathy is a common complication of diabetes that leads to severe postural hypotension, exercise intolerance, and increased incidence of silent myocardial infarction. Objective To determine the variability of heart rate (HR) and systolic blood pressure (SBP) in recently diagnosed diabetic patients. Methods The study included 30 patients with a diagnosis of type 2 diabetes of less than 2 years and 30 healthy controls. We used a Finapres® device to measure during five minutes beat-to-beat HR and blood pressure in three experimental conditions: supine position, standing position, and rhythmic breathing at 0.1 Hz. The results were analyzed in the time and frequency domains. Results In the HR analysis, statistically significant differences were found in the time domain, specifically on short-term values such as standard deviation of NN intervals (SDNN), root mean square of successive differences (RMSSD), and number of pairs of successive NNs that differ by more than 50 ms (pNN50). In the BP analysis, there were no significant differences, but there was a sympathetic dominance in all three conditions. The baroreflex sensitivity (BRS) decreased in patients with early diabetes compared with healthy subjects during the standing maneuver. Conclusions There is a decrease in HR variability in patients with early type 2 diabetes. No changes were observed in the BP analysis in the supine position, but there were changes in BRS with the standing maneuver, probably due to sympathetic hyperactivity. PMID:26176187

  14. A new bit-serial systolic multiplier over GF(2/sup m/)

    SciTech Connect

    Zhou, B.B.

    1988-06-01

    A new bit-serial systolic array is developed to compute multiplications over GF(2/sup m/). In contrast to another systolic multiplier, this new systolic algorithm allows the input elements to enter a linear systolic array in the same order and the system only requires one control signal.

  15. A Josephson systolic array processor for multiplication/addition operations

    SciTech Connect

    Morisue, M.; Li, F.Q.; Tobita, M.; Kaneko, S. )

    1991-03-01

    A novel Josephson systolic array processor to perform multiplication/addition operations is proposed. The systolic array processor proposed here consists of a set of three kinds of interconnected cells of which main circuits are made by using SQUID gates. A multiplication of 2 bits by 2 bits is performed in the single cell at a time and an addition of three data with two bits is simultaneously performed in an another type of cell. Furthermore, information in this system flows between cells in a pipeline fashion so that a high performance can be achieved. In this paper the principle of Josephson systolic array processor is described in detail and the simulation results are illustrated for the multiplication/addition of (4 bits {times} 4 bits + 8 bits). The results show that these operations can be executed in 330ps.

  16. Design of the PSC: a programmable systolic chip

    SciTech Connect

    Fisher, A.L.; Kung, H.T.; Monier, L.M.; Walker, H.; Dohi, Y.

    1983-01-01

    The programmable systolic chip (PSC) is a high performance special-purpose single-chip microprocessor intended to be used in groups of tens or hundreds for the efficient implementation of a broad variety of systolic arrays. For implementing these systolic arrays, the psc is expected to be at least an order of magnitude more efficient than conventional microprocessors. The development of the psc design, from initial concept to a silicon layout, took slightly less than a year. This project represents an integration of many disciplines including applications, algorithms, architecture, microprocessor design, and chip layout. The author describes the goals of the project, the design process, major design features and current status. 22 references.

  17. Systolic array for fast computation of moment invariants

    NASA Astrophysics Data System (ADS)

    Liu, Jianguo; Chan, Francis H. Y.; Li, H. F.; Lam, F. K.

    1998-09-01

    Moment invariants, by virtue of invariance properties under translation, scaling and rotation, have played an important role in pattern recognition and computer vision. In the present paper, extending the systolic array for computing moments, a global systolic structure for fast computation of moment invariants has been proposed. This structure fully exploits parallelism of the network architecture and reduces computational time complexity from O(n2) in the case of direct computation to O(n) (n denotes image size). The systolic structure nearly consists of adders with area complexity O(n) and are highly regular and structurally very simple, resulting in simple hardware implementation. The method is suitable for both binary images and gray level images and is also suitable for image sequence moments.

  18. Systolic multipliers for finite fields GF(2 exp m)

    NASA Technical Reports Server (NTRS)

    Yeh, C.-S.; Reed, I. S.; Truong, T. K.

    1984-01-01

    Two systolic architectures are developed for performing the product-sum computation AB + C in the finite field GF(2 exp m) of 2 exp m elements, where A, B, and C are arbitrary elements of GF(2 exp m). The first multiplier is a serial-in, serial-out one-dimensional systolic array, while the second multiplier is a parallel-in, parallel-out two-dimensional systolic array. The first multiplier requires a smaller number of basic cells than the second multiplier. The second multiplier needs less average time per computation than the first multiplier, if a number of computations are performed consecutively. To perform single computations both multipliers require the same computational time. In both cases the architectures are simple and regular and possess the properties of concurrency and modularity. As a consequence, they are well suited for use in VLSI systems.

  19. FFT Computation with Systolic Arrays, A New Architecture

    NASA Technical Reports Server (NTRS)

    Boriakoff, Valentin

    1994-01-01

    The use of the Cooley-Tukey algorithm for computing the l-d FFT lends itself to a particular matrix factorization which suggests direct implementation by linearly-connected systolic arrays. Here we present a new systolic architecture that embodies this algorithm. This implementation requires a smaller number of processors and a smaller number of memory cells than other recent implementations, as well as having all the advantages of systolic arrays. For the implementation of the decimation-in-frequency case, word-serial data input allows continuous real-time operation without the need of a serial-to-parallel conversion device. No control or data stream switching is necessary. Computer simulation of this architecture was done in the context of a 1024 point DFT with a fixed point processor, and CMOS processor implementation has started.

  20. Design and programming of systolic array cells for signal processing

    SciTech Connect

    Smith, R.A.W.

    1989-01-01

    This thesis presents a new methodology for the design, simulation, and programming of systolic arrays in which the algorithms and architecture are simultaneously optimized. The algorithms determine the initial architecture, and simulation is used to optimize the architecture. The simulator provides a register-transfer level model of a complete systolic array computation. To establish the validity of this design methodology two novel programmable systolic array cells were designed and programmed. The cells were targeted for applications in high-speed signal processing and associated matrix computations. A two-chip programmable systolic array cell using a 16-bit multiplier-accumulator chip and a semi-custom VLSI controller chip was designed and fabricated. A low chip count allows large arrays to be constructed, but the cell is flexible enough to be a building-block for either one- or two-dimensional systolic arrays. Another more flexible and powerful cell using a 32-bit floating-point processor and a second VLSI controller chip was also designed. It contains several architectural features that are unique in a systolic array cell: (1) each instruction is 32 bits, yet all resources can be updated every cycle, (2) two on-chip interchangeable memories are used, and (3) one input port can be used as either a global or local port. The key issues involved in programming the cells are analyzed in detail. A set of modules is developed which can be used to construct large programs in an effective manner. The utility of this programming approach is demonstrated with several important examples.

  1. Arrhythmias and Electrocardiographic Changes in Systolic Heart Failure

    PubMed Central

    Devkota, Ashok; Bakhit, Ahmed; Dufresne, Alix; Oo, Aung Naing; Parajuli, Premraj; Manhas, Saveena

    2016-01-01

    Background: Heart failure is a common condition that that leads to hospitalization. It is associated with various atrial and ventricular arrhythmias. Aim: The aim of this study is to find common arrhythmias and electrocardiographic changes in hospitalized patients who have systolic heart failure. Materials and Methods: This is a retrospective study of medical records, and electrocardiograms (EKGs) of 157 patients admitted to our hospital who had systolic heart failure with ejection fraction (EF) <50% on echocardiogram. Based on EF, the patients were divided into two groups; one with EF ≤ 35% and the other with EF > 35%. Twelve-lead EKG of these patients was studied to identify common arrhythmia and demographic variables; laboratory results were compared to identify the differences. Results: A total of 157 patients with systolic heart failure, 63.7% had an EF ≤ 35%. Hypertension 82.8%, diabetes 49%, coronary artery disease 40.8%, chronic obstructive pulmonary disease or bronchial asthma 22.3%, and stroke 12.1% were common associated co-morbidities. On analysis of EKG, 28.6% had tachycardia, 21.9% had prolonged PR > 200 ms, 16.3% had wide QRS > 120 ms, 70.7% had prolonged corrected QT (QTc), and 42.2% had left axis deviation. The most common arrhythmias were sinus tachycardia and atrial fibrillation/flutter which were found in 14.6% and 13.4%, respectively. The left ventricular hypertrophy was a common abnormality found in 22.4% followed by ventricular premature contractions 18.4%, atrial premature contractions 9.5%, and left bundle branch block 6.1%. Patients with severe systolic heart failure had prolonged QRS (P = 0.02) and prolonged QTc (P = 0.01) as compared to the other group. Conclusions: Sinus tachycardia and atrial fibrillation/flutter were common arrhythmias in patients with systolic heart failure. Patients with severe systolic heart failure had statistically significant prolongation of the QRS duration and QTc interval. PMID:27213140

  2. Content addressable systolic array for sparse matrix computation

    SciTech Connect

    Wing, O.

    1983-01-01

    A systolic array is proposed which is specifically designed to solve a system of sparse linear equations. The array consists of a number of processing elements connected in a ring. Each processing element has its own content addressable memory where the nonzero elements of the sparse matrix are stored. Matrix elements to which elementary operations are applied are extracted from the memory by content addressing. The system of equations is solved in a systolic fashion and the solution is obtained in nz+5n-2 steps where nz is the number of nonzero elements along and below the diagonal and n is the number of equations. 13 references.

  3. Systolic array for fast computation of discrete cosine transform

    NASA Astrophysics Data System (ADS)

    Liu, Jianguo; Li, H. F.; Chan, Francis H. Y.; Lam, F. K.

    1998-09-01

    Discrete cosine transform (DCT) is widely used in signal processing. This paper presents a novel approach to perform DCT. DCT is expressed in terms of discrete moments and a systolic array for computing DCT with only a few multiplications and without any cosine evaluations has been proposed. The execution time of the systolic array is only O(Nlog2N/log2log2N) in computing 1D DCT. The approach is also applicable to multiple dimensional DCT and DCT inverses.

  4. Low Power Systolic Array Based Digital Filter for DSP Applications.

    PubMed

    Karthick, S; Valarmathy, S; Prabhu, E

    2015-01-01

    Main concepts in DSP include filtering, averaging, modulating, and correlating the signals in digital form to estimate characteristic parameter of a signal into a desirable form. This paper presents a brief concept of low power datapath impact for Digital Signal Processing (DSP) based biomedical application. Systolic array based digital filter used in signal processing of electrocardiogram analysis is presented with datapath architectural innovations in low power consumption perspective. Implementation was done with ASIC design methodology using TSMC 65 nm technological library node. The proposed systolic array filter has reduced leakage power up to 8.5% than the existing filter architectures. PMID:25922854

  5. Systolic time interval data acquisition system. Specialized cardiovascular studies

    NASA Technical Reports Server (NTRS)

    Baker, J. T.

    1976-01-01

    The development of a data acquisition system for noninvasive measurement of systolic time intervals is described. R-R interval from the ECG determines instantaneous heart rate prior to the beat to be measured. Total electromechanical systole (Q-S2) is measured from the onset of the ECG Q-wave to the onset of the second heart sound (S2). Ejection time (ET or LVET) is measured from the onset of carotid upstroke to the incisure. Pre-ejection period (PEP) is computed by subtracting ET from Q-S2. PEP/ET ratio is computed directly.

  6. Systolic Blood Pressure Intervention Trial (SPRINT) and Target Systolic Blood Pressure in Future Hypertension Guidelines.

    PubMed

    Egan, Brent M; Li, Jiexiang; Wagner, C Shaun

    2016-08-01

    The Systolic Blood Pressure (SBP, mm Hg) Intervention Trial (SPRINT) showed that targeting SBP <120 mm Hg (intensive treatment, mean SBP: 121.5 mm Hg) versus <140 (standard treatment, mean SBP: 134.6 mm Hg) reduced cardiovascular events 25%. SPRINT has 2 implicit assumptions that could impact future US hypertension guidelines: (1) standard therapy controlled SBP similarly to that in adults with treated hypertension and (2) intensive therapy produced a lower mean SBP than in adults with treated hypertension and SBP <140 mm Hg. To examine these assumptions, US National Health and Nutrition Examination Survey 2009 to 2012 data were analyzed on 3 groups of adults with treated hypertension: group 1 consisted of SPRINT-like participants aged ≥50 years; group 2 consisted of participants all aged ≥18 years; and group 3 consisted of participants aged ≥18 years excluding group 1 but otherwise similar to SPRINT-like participants except high cardiovascular risk. Mean SBPs in groups 1, 2, and 3 were 133.0, 130.1, and 124.6, with 66.2%, 72.2%, and 81.9%, respectively, controlled to SBP <140; 68.3%, 74.8%, and 83.4% of the controlled subset had SBP <130. Mean SBPs in those controlled to <140 were 123.3, 120.9, and 118.9, respectively. Among US adults with treated hypertension, (1) the SPRINT-like group had higher mean SBP than comparison groups, yet lower than SPRINT standard treatment group and (2) among groups 1 to 3 with SBP <140, SBP values were within <3 mm Hg of SPRINT intensive treatment. SPRINT results suggest that treatment should be continued and not reduced when treated SBP is <130, especially for the SPRINT-like subset. Furthermore, increasing the percentage of treated adults with SBP <140 could approximate SPRINT intensive treatment SBP without lowering treatment goals. PMID:27354422

  7. Algorithmic study on systolic array structures. Master's thesis

    SciTech Connect

    Souza, L.J.

    1985-06-01

    Computation bound problems impose a severe burden on the CPU. In order to speed up computation, specific problems that are identified as the main burden can be done using parallel processing. In this way, the time consuming tasks can be executed on specially tailored hardware. This hardware is designed to implement an algorithm-oriented parallel-processing structure that works more efficiently than the CPU for these specific tasks. This thesis is a study of the mapping of the algorithms onto a kind of structure called systolic array. The development and utilization of a software tool designed to assist on such analysis is presented here. This tool, named Systolic Array Graphics Simulator (SYSGRAS), has the capability to represent any type of systolic array, no matter how complex the cells and structure are. Because of the capability of SYSGRAS, an interactive computer program simulator, the study of systolic arrays is simplified. The complexity of the time-space relationships is analyzed with the help of some color-graphics techniques. The visualization of the data interaction is thus enhanced and the user is alleviated from the burden of keeping track of partial results and can dedicate attention to the processing algorithm.

  8. Guidelines for efficient use of optical systolic array processors

    SciTech Connect

    Casasent, D.

    1983-01-01

    The design, error analysis, component accuracy required, computational capacity, data flow and pipelining, plus the algorithm and application all seriously impact the use of optical systolic array processors. The author provides initial remarks, results, examples and solutions for each of these issues. 20 references.

  9. Predictors of high central blood pressure in young with isolated systolic hypertension

    PubMed Central

    Radchenko, GD; Torbas, OO; Sirenko, Yu M

    2016-01-01

    Objective According to the European Society of Cardiology/European Society of Hypertension 2013 guidelines, evaluation of aortic blood pressure (BP) is needed in young with isolated systolic hypertension (ISH), but using special devices is not common, especially in Ukraine, where only a few centers have these devices. The purpose of our study was to identify the simple clinical predictors for differentiation (with or without elevated aortic systolic BP [SBP]) of the young with ISH without the need for further extensive work-up. Patients and methods The study included 44 young men (mean age: 32.2±1.3 years) with office SBP ≥140 mmHg and office diastolic BP (DBP) <90 mmHg (average: 153.4±2.1 mmHg and 83.4±1.7 mmHg, respectively). The following procedures were performed in all the subjects: body weight and height evaluation; measurement of office SBP, DBP, and heart rate; ambulatory BP monitoring; measurement of pulse wave velocity in arteries of elastic and muscle types and central SBP (cSBP); biochemical blood tests; electrocardiography; echocardiography; and carotid ultrasound investigations. Step-by-step multifactor regression analyses were used for finding the predictors of high cSBP. Results Depending on the cSBP level, all the patients were divided into two groups: first group (n=17), subjects with normal cSBP, and second group (n=27), subjects with elevated cSBP. Patients in the second group were significantly older, with less height and higher body mass index; they had significantly higher levels of office SBP and DBP. Characteristics of target organ damage were within normal limits in both groups and did not differ significantly. Only pulse wave velocity in arteries of elastic type was significantly higher in the second group. The independent predictors of increased cSBP were as follows: height ≤178 cm (β=7.038; P=0.05), body weight ≥91 kg (β=5.53, P=0.033), and the level of office DBP ≥80 mmHg (β=4.43; P=0.05). The presence of two or three of

  10. Effect of angiotensin receptor blockade on central aortic systolic blood pressure in hypertensive Asians measured using radial tonometry: an open prospective cohort study

    PubMed Central

    Teong, Hui Hwang; Chin, Adeline Mei Lin; Sule, Ashish Anil; Tay, Jam Chin

    2016-01-01

    INTRODUCTION Central aortic systolic pressure (CASP) has been shown to be a stronger predictor of cardiovascular events than brachial blood pressure (BP). Different classes of drugs have differential effects on CASP and brachial BP. This open prospective cohort study aimed to observe changes in CASP (measured using radial tonometry) among hypertensive Asians after 12 weeks of treatment with valsartan, an angiotensin receptor blocker (ARB). METHODS Patients with treatment-naïve hypertension or uncontrolled hypertension who were on non-ARB therapy were eligible for inclusion. Patients with uncontrolled BP (i.e. ≥ 140/90 mmHg) received valsartan for 12 weeks. The patients’ brachial systolic and diastolic BP (SBP and DBP), and CASP changes were monitored using the BPro® watch. RESULTS The mean age of the 44 enrolled patients was 35 years. At baseline, the mean BP and CASP were 150.2/91.4 ± 10.6/9.4 mmHg and 136.3 ± 12.2 mmHg, respectively. Valsartan reduced SBP, DBP and CASP by 14.9 ± 10.7 mmHg, 10.9 ± 8.4 mmHg and 15.3 ± 10.9 mmHg, respectively (all p < 0.001). Every 1.0-mmHg reduction in brachial SBP resulted in a 0.8-mmHg reduction in CASP (p < 0.001). A CASP cut-off of 122.5 mmHg discriminated between controlled and uncontrolled BP (sensitivity 74%, specificity 88%). CONCLUSION Using radial tonometry, we demonstrated good correlation between CASP and brachial SBP reductions after 12 weeks of treatment with valsartan in our study cohort. Correlation analysis between CASP and SBP reductions may be useful for demonstrating whether a drug is able to lower CASP beyond lowering SBP. PMID:26875683

  11. A comparison of systolic blood pressure measurement obtained using a pulse oximeter, and direct systolic pressure measurement in anesthetized sows.

    PubMed Central

    Caulkett, N A; Duke, T; Bailey, J V

    1994-01-01

    Systolic blood pressure measurement obtained with a pulse oximeter has been compared to values obtained by other indirect methods in man. Direct pressure measurement is subject to less error than indirect techniques. This study was designed to compare systolic pressure values obtained using a pulse oximeter, with values obtained by direct arterial pressure measurement. The pulse oximeter waveform was used as an indication of perfusion. A blood pressure cuff was applied proximal to the pulse oximeter probe. The cuff was inflated until the oximeter waveform disappeared, this value was recorded as the systolic pressure at the disappearance of the waveform (SPD). The cuff was inflated to a pressure > 200 mmHg, then gradually deflated until the waveform reappeared, this value was recorded as the systolic pressure at reappearance of the waveform (SPR). The average of the two values, SPD and SPR, was calculated and recorded as SPA. The study was performed in sows (n = 21) undergoing cesarean section under epidural anesthesia and IV sedation. A total of 280 measurements were made of SPD, SPR and SPA. Regression analysis of SPA and direct measurement revealed a correlation coefficient (r) of 0.81. Calculation of mean difference (bias) and standard deviation of the bias (precision) for direct pressure--SPA revealed a value of 1.3 +/- 12.1. When compared with direct measurement, the correlation of this technique was similar to that recorded for other indirect techniques used in small animals. This indicates that this technique would be useful for following systolic pressure trends.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8004540

  12. BP details new recycling process

    SciTech Connect

    Chynoweth, E.

    1992-04-22

    BP Chemicals (London) is developing a preprocessing thermal cracker for recycling mixed plastics waste as an add-on to existing petrochemicals or refinery complexes. The company is currently discussing the technology with other plastic producers to {open_quotes}move forward together,{close_quotes} say Serge Huybrechts, branch R&D manager at BP Chemicals at Grangemouth. He says the unit would be able to deliver an intermediate feed of similar composition to chemical naphtha for chemical or refinery processes including steam cracking, catalytic cracking, coking, gasification, and hydrocracking. In comparison, pyrolysis gives a range of products, from light gas to heavy aromatics, that are difficult to integrate into existing equipment.

  13. Left Ventricular Systolic and Diastolic Function in Patients With Apical Ballooning Syndrome Compared With Patients With Acute Anterior ST-Segment Elevation Myocardial Infarction: A Functional Paradox

    PubMed Central

    Park, Seong-Mi; Prasad, Abhiram; Rihal, Charanjit; Bell, Malcolm R.; Oh, Jae K.

    2009-01-01

    OBJECTIVE: To compare left ventricular (LV) systolic and diastolic function in patients with apical ballooning syndrome (ABS) and those with acute myocardial infarction (AMI) using 2-dimensional Doppler echocardiography and strain rate imaging (SRI). PATIENTS AND METHODS: We prospectively enrolled patients with newly diagnosed AMI and ABS who had akinetic apical walls. Both 2-dimensional Doppler echocardiography and SRI were performed on hospital day 1 or within 24 hours of primary percutaneous coronary intervention. RESULTS: Twenty-four patients with AMI and 13 patients with ABS (mean ± SD age, 63±15 vs 73±12 years; P=.03) were prospectively enrolled in the study from October 3, 2005 through July 12, 2006. The mean ± SD LV end-diastolic volume was larger (58.1±9.1 vs 45.2±10.6 mL/m2; P<.001) and the mean ± SD LV ejection fraction was lower (35%±6% vs 43%±9%; P=.006) in patients with ABS compared with patients with AMI. The early diastolic mitral annular velocity was similar (0.06±0.02 vs 0.06±0.02 m/s; P=.85) in both groups, but the ratio of early diastolic mitral valve inflow velocity to early diastolic mitral annulus velocity was higher in patients with AMI than in patients with ABS (16.3±6.9 vs 12.2±3.2; P=.05). The systolic strain rate was decreased at the apex in both groups (P=.98). Both the early diastolic strain rate of the apex (0.64±0.24 vs 0.48±0.30 s-1; P=.04) and the postsystolic shortening index of the apex (61%±15% vs 45%±23%; P=.006) were higher in the patients with ABS than in those with AMI. However, early diastolic SR was higher in the akinetic apical walls of patients with AMI with recovery than those with no recovery (0.64±0.35 vs 0.43±0.25 s-1; P=.04) and was similar between akinetic apical walls of patients with AMI with recovery and the akinetic apical walls of ABS. CONCLUSION: Compared with patients with AMI, those with ABS showed the functional paradox of worse initial LV systolic function with larger LV size but better

  14. Albuminuria in relation to the single and combined effects of systolic and diastolic blood pressure in Chinese.

    PubMed

    Sheng, Chang-Sheng; Liu, Ming; Zou, Jun; Huang, Qi-Fang; Li, Yan; Wang, Ji-Guang

    2013-06-01

    We investigated the single and combined effects of systolic (SBP) and diastolic blood pressure (DBP) on albuminuria in Chinese. We measured blood pressure (BP), anthropometry and urinary excretions of albumin and creatinine, and defined albuminuria as a urinary albumin-to-creatinine ratio of at least 17 and 25 mg/g in men and women, respectively. The 1068 participants (mean age 56.3 years) included 407 (38.5%) men and 410 (38.4%) hypertensive patients. A J-shaped relationship between the risk of albuminuria and BP was observed for both SBP (mean ± SD, 126.1 ± 18.9 mmHg) and DBP (77.1 ± 9.4 mmHg) with nadir levels of 110 mmHg and 70 mmHg, respectively. The risk of albuminuria was significantly (p ≤ 0.01) associated with DBP in the subjects with a SBP of at least 130 mmHg and with SBP in subjects with a DBP of at least 80 mmHg, and inversely and significantly (p = 0.04) associated with SBP in subjects with a DBP below 70 mmHg. In conclusion, as far as albuminuria is concerned, there is indeed a J-shaped phenomenon. However, it has a nadir level far below the currently recommended target BP of 140/90 or 130/80 mmHg. PMID:23244371

  15. Systolic multiplier for finite fields gf(2/sup m/)

    SciTech Connect

    Yeh, C.S.; Reed, I.S.

    1983-01-01

    A systolic architecture is developed for performing the product-sum computation, ab+c, in the finite field gf(2/sup m/) of 2/sup m/ elements, where a, b and c are arbitrary elements of gf(2/sup m/). The multiplier is a serial-in, serial-out, one-dimensional systolic array. This multiplier for gf(2/sup m/) requires m basic cells. The average time per computation of the multiplier is m time units if a number of computations are computed consecutively. To perform an isolated computation the multiplier requires 3m time units. The architecture is simple and regular and possesses the desirable properties of concurrency and modularity and is well suited for use. 10 references.

  16. Systolic emulator experimentation. Report for April 1987-April 1990

    SciTech Connect

    Smith, R.N.; Fenton, M.W.

    1990-07-01

    Adaptive spatial filtering or adaptive antenna nulling techniques have been used to remove or eliminate directional electromagnetic interferences or unwanted signals from getting into radio receivers. This signal processing technique has been studied for many years. Many systems have been proposed, some have built and a few have been fielded. High speed parallel processors are beginning to show promise in providing real-time solutions for meeting the processing requirements needed for space applications. One type of high speed parallel processor architecture is called systolic. The name arises from the way the data pulses through the cell-like structure of the processor in a prescribed pipelined manner. Effective implementation of adaptive signal processing techniques using systolic array processors, especially, required careful matching between the algorithm to be performed and the processor architecture. This process of matching algorithm and architecture can be facilitated by computer emulation.

  17. LU and Cholesky decomposition on an optical systolic array processor

    NASA Technical Reports Server (NTRS)

    Casasent, D.; Ghosh, A.

    1983-01-01

    Direct solutions of matrix-vector equations on an optical systolic array processor are considered. The solutions are discussed and a parallel algorithm for LU matrix decomposition that is very attractive for an optical realization is formulated. It is noted that when direct techniques are used, it is preferable to realize the matrix decomposition on an optical system and to utilize a digital processor for the solution of the simplified resultant matrix-vector problem. One method of realizing LU matrix decomposition on a new frequency-multiplexed optical systolic array matrix-matrix processor is described. A simple method for extending the process of LU decomposition to Cholesky decomposition on the optical processor is discussed.

  18. Fabrication of fault-tolerant systolic array processors

    SciTech Connect

    Golovko, V.A.

    1995-05-01

    Methods for designing fault-tolerant systolic array processors are discussed. Several ways of bypassing faulty elements in configurations, which depend on an input-data flow organization, are suggested. An analysis of the additional hardware costs of providing fault tolerance by various techniques and for various levels of redundancy is presented. Hadamard fault-tolerant processor design was used to illustrate the efficiency of the techniques suggested.

  19. Two-Dimensional Systolic Array For Kalman-Filter Computing

    NASA Technical Reports Server (NTRS)

    Chang, Jaw John; Yeh, Hen-Geul

    1988-01-01

    Two-dimensional, systolic-array, parallel data processor performs Kalman filtering in real time. Algorithm rearranged to be Faddeev algorithm for generalized signal processing. Algorithm mapped onto very-large-scale integrated-circuit (VLSI) chip in two-dimensional, regular, simple, expandable array of concurrent processing cells. Processor does matrix/vector-based algebraic computations. Applications include adaptive control of robots, remote manipulators and flexible structures and processing radar signals to track targets.

  20. Preserved Left Ventricular, Systolic Function in Clinical Congestive Heart Failure

    PubMed Central

    Lee, Bang Hun; Kim, Jeong Hyun; Lim, Heon Kil; Lee, Chung Kyun

    1987-01-01

    Although clinical congestive heart failure (CHF) is associated with significant left ventricular (LV) systolic dysfunction, recently it has been recognized that LV diastolic dysfunction also may occur in the absence of abnormal systolic performance. A retrospective study evaluated 23 patients with myocardial infarction and CHF who had undergone multigated blood pool scintigraphy and were found to have normal LV ejection fraction (≥ 50%). Average rapid filling velocity (RFV) and slow filling velocity (SFV) were both significantly reduced in CHF patients (5.1 ± 1.3 unit/s, 2.2 ± 1.4 unit/s respectively) compared with normal control group (3.9 ± 1.2 unit/s, 1.3 ± 0.8 unit/s respectively). Rapid filling time and total diastolic time were also significantly prolonged in CHF patients (p<0.01, p<0.05 respectively). There were no significant changes in heart rate and blood pressure between two groups. Thus, normal systolic LV function is encountered in patients with CHF and it appears to be prudent to evaluate diastolic performance as well for optimal therapeutic strategies for CHF patients. PMID:3154818

  1. Systolic array architecture for real-time Gabor decomposition

    NASA Astrophysics Data System (ADS)

    Iyengar, Giridharan; Panchanathan, Sethuraman

    1992-11-01

    In this paper, we propose a combined systolic array--content addressable memory architecture for image compression using Gabor decomposition. Gabor decomposition is attractive for image compression since the basis functions match the human visual profiles. Gabor functions also achieve the lowest bound on the joint entropy of data. However these functions are not orthogonal and hence an analytic solution for the decomposition does not exist. Recently it has been shown that Gabor decomposition can be computed as a multiplication between a transform matrix and a vector of image data. Systolic arrays are attractive for matrix multiplication problems and content addressable memories (CAM) offer fast means of data access. For an n X n image, the proposed architecture for Gabor decomposition consists of a linear systolic array of n processing elements each with a local CAM. Simulations and complexity studies show that this architecture can achieve real-time performance with current technology. This architecture is modular and regular and hence it can be implemented in VLSI as a codec.

  2. Systolic array architecture for convolutional decoding algorithms: Viterbi algorithm and stack algorithm

    SciTech Connect

    Chang, C.Y.

    1986-01-01

    New results on efficient forms of decoding convolutional codes based on Viterbi and stack algorithms using systolic array architecture are presented. Some theoretical aspects of systolic arrays are also investigated. First, systolic array implementation of Viterbi algorithm is considered, and various properties of convolutional codes are derived. A technique called strongly connected trellis decoding is introduced to increase the efficient utilization of all the systolic array processors. The issues dealing with the composite branch metric generation, survivor updating, overall system architecture, throughput rate, and computations overhead ratio are also investigated. Second, the existing stack algorithm is modified and restated in a more concise version so that it can be efficiently implemented by a special type of systolic array called systolic priority queue. Three general schemes of systolic priority queue based on random access memory, shift register, and ripple register are proposed. Finally, a systematic approach is presented to design systolic arrays for certain general classes of recursively formulated algorithms.

  3. The effect of chronic administration of safranal on systolic blood pressure in rats.

    PubMed

    Imenshahidi, Mohsen; Razavi, Bibi Marjan; Faal, Ayyoob; Gholampoor, Ali; Mousavi, Seyed Mehran; Hosseinzadeh, Hossein

    2015-01-01

    Safranal, the main component of Crocus sativus essential oil, exhibits different pharmacological activities. In this study, the effects of safranal, on blood pressure of normotensive and desoxycorticosterone acetate (DOCA) - salt induced hypertensive rats in chronic administration were investigated. Three doses of safranal (1, 2 and 4 mg/Kg/day) and spironolactone (50 mg/Kg/day) were administrated to the different groups of normotensive and hypertensive rats (at the end of 4 weeks treatment by DOCA-salt) for Five weeks. Then the effects of safranal on mean systolic blood pressure (MSBP) and heart rate (HR) were evaluated using tail cuff method. The duration of effect of safranal on SBP, was also evaluated. Our results indicated that chronic administration of safranal could reduce the MSBP in DOCA salt treated rats in a dose dependent manner. Safranal did not decrease the MSBP in normotensive rats. The data also showed that antihypertensive effects of safranal did not persist. In summary, our results showed that safranal exhibits antihypertensive and normalizing effect on BP in chronic administration. PMID:25901167

  4. BP Targets in Hypertension: What Should We Do Now That SPRINT Is Out?

    PubMed

    Bhatt, Hemal; Ghazi, Lama; Calhoun, David; Oparil, Suzanne

    2016-10-01

    Systolic blood pressure (SBP) is an important predictor of cardiovascular disease (CVD) outcomes. Lowering SBP has been shown to reduce CVD morbidity and mortality, but the optimal SBP target continues to be a topic of intense debate. The Systolic Blood Pressure Intervention Trial (SPRINT) reported a significantly lower risk for CVD outcomes and all-cause mortality by targeting SBP <120 mmHg compared with <140 mmHg in a population of hypertensive persons at high CV risk. In this review, we discuss the strengths, limitations, and generalizability of SPRINT findings to other hypertensive populations that were excluded from the trial, including those with diabetes or prior stroke, <50 years old, and at lower CVD risk. We will focus on the implications of SPRINT findings for appropriate BP targets in high-risk groups of hypertensive persons, including the elderly and those with chronic kidney disease (CKD). We will also address the cost-effectiveness of intensive BP treatment as implemented in SPRINT and the implications of SPRINT for health care policy and future BP guidelines. PMID:27566331

  5. The 24-Hour Job Machine: Computerized Applicant Systems.

    ERIC Educational Resources Information Center

    Wiedman, Lisa W.

    1986-01-01

    The evolution of computerized job applicant systems is described and compared to that of computerized banking systems; the characteristics of such systems in the future, especially for minimizing data entry and maximizing accessibility, are then outlined and illustrated with the Carnegie-Mellon University system. (MSE)

  6. Collection of a 24-Hour Urine Specimen (Beyond the Basics)

    MedlinePlus

    ... the Licensed Materials from any location via the Internet. b. STANDALONE WORKSTATION: A standalone subscription permits multiple ... computer. A Standalone Workstation license does not include Internet access to the Licensed Materials. c. INSTITUTIONAL SUBSCRIPTION: ...

  7. Boerhaave's syndrome: Experience with patients presenting later than 24 hours.

    PubMed

    Ganguly, Amit; Porwal, Manish; Khandeparkar, Jagdish

    2015-01-01

    Boerhaave's syndrome is the most sinister cause of esophageal perforation. Clinical presentation is vague. Diagnostic delays are frequent. As condition is rare therefore no consensus exists on management. A wide variety of management options are described in literature, each with its advantages and disadvantages. We present our experience of managing these cases which presented after 24 hr. Of onset of symptoms with emphasis on primary reinforced repair as first line surgical option. PMID:27522739

  8. Nutrition habits in 24-hour mountain bike racers.

    PubMed

    Chlíbková, Daniela; Knechtle, Beat; Rosemann, Thomas; Tomášková, Ivana; Chadim, Vlastimil; Shortall, Marcus

    2014-01-01

    We investigated seventy-four ultra-mountain bikers (MTBers) competing in the solo category in the first descriptive field study to detail nutrition habits and the most common food before during and after the 24 hour race using questionnaires. During the race, bananas (86.5%), energy bars (50.0%), apples (43.2%) and cheese (43.2%) were the most commonly consumed food, followed by bread (44.6%), rice (33.8%) and bananas (33.8%) after the race. Average fluid intake was 0.5 ± 0.2 l/h. The main beverage was isotonic sports drink (82.4%) during and pure water (66.2%) after the race. The most preferred four supplements in the four weeks before, the day before, during and after the race were vitamin C (35.1%), magnesium (44.6%), magnesium (43.2%) and branched-chain amino acids (24.3%), respectively. Total frequency of food intake (30.6 ± 10.5 times/24 hrs) was associated with fluid intake (r = 0.43, P = 0.04) and both were highest at the beginning of the race and lower during the night hours and the last race segment in a subgroup of twenty-three ultra-MTBers. Supplement intake frequency (6.8 ± 8.4 times/24 hrs) was highest during the night hours and lower at the beginning and end of the race. Elevated food and fluid intake among participants tracked across all race segments (P < 0.001). In conclusion, the nutrition strategy employed by ultra-MTBers was similar to those demonstrated in previous studies of ultra-cyclists with some exceptions among selected individuals. PMID:25674455

  9. Elimination of 24-hour continuous medical resident duty in Quebec

    PubMed Central

    Hamadani, Fadi; Deckelbaum, Dan; Shaheen, Mohammed; Sauvé, Alexandre; Dumitra, Sinziana; Ahmed, Najma; Latulippe, Jean-François; Balaa, Fady; Walsh, Mark; Fata, Paola

    2016-01-01

    Summary In 2012 Quebec limited continuous in-hospital duty to 16 consecutive hours for all residents regardless of postgraduate (PGY) level. The new restrictions in Quebec appeared to have a profound, negative effect on the quality of life of surgical residents at McGill University and a perceived detrimental effect on the delivery of surgical education and patient care. Here we discuss the results of a nationwide survey that we created and distributed to general surgery residents across Canada to capture and compare their perceptions of the changes to duty hour restrictions. PMID:26574704

  10. Sun Blasts 6 CMEs in 24 Hour Period

    NASA Video Gallery

    This movie from the chronograph on board the SOlar and Heliospheric Observatory (SOHO), shows the sun's atmosphere – the corona – from September 17 to September 20. The sun let loose with at ...

  11. A 24-hour remote surveillance system for terrestrial wildlife studies

    USGS Publications Warehouse

    Sykes, P.W., Jr.; Ryman, W.E.; Kepler, C.B.; Hardy, J.W.

    1995-01-01

    The configuration, components, specifications and costs of a state-of-the-art closed-circuit television system with wide application for wildlife research and management are described. The principal system components consist of color CCTV camera with zoom lens, pan/tilt system, infrared illuminator, heavy duty tripod, coaxial cable, coaxitron system, half-duplex equalizing video/control amplifier, timelapse video cassette recorder, color video monitor, VHS video cassettes, portable generator, fuel tank and power cable. This system was developed and used in a study of Mississippi sandhiIl Crane (Grus canadensis pratensis) behaviors during incubation, hatching and fledging. The main advantages of the system are minimal downtime where a complete record of every event, its time of occurrence and duration, are permanently recorded and can be replayed as many times as necessary thereafter to retrieve the data. The system is particularly applicable for studies of behavior and predation, for counting individuals, or recording difficult to observe activities. The system can be run continuously for several weeks by two people, reducing personnel costs. This paper is intended to provide biologists who have litte knowledge of electronics with a system that might be useful to their specific needs. The disadvantages of this system are the initial costs (about $9800 basic, 1990-1991 U.S. dollars) and the time required to playback video cassette tapes for data retrieval, but the playback can be sped up when litte or no activity of interest is taking place. In our study, the positive aspects of the system far outweighed the negative.

  12. Rethinking the Youth Weight Debate: The 24 Hour Day

    ERIC Educational Resources Information Center

    Dodd, Graham; Biggs, Sarah; Agley, Daniel; Dollman, James; Lushington, Kurt

    2008-01-01

    Approaches to weight management have traditionally focussed on caloric intake versus caloric expenditure. Despite a range of interventions based on these approaches, the proportion of overweight children and adolescents continues to rise. There are increasing indications that other factors, such as sleep duration, may be at play. This commentary…

  13. Attenuated sympathetic nerve responses after 24 hours of bed rest

    NASA Technical Reports Server (NTRS)

    Khan, Mazhar H.; Kunselman, Allen R.; Leuenberger, Urs A.; Davidson, William R Jr; Ray, Chester A.; Gray, Kristen S.; Hogeman, Cynthia S.; Sinoway, Lawrence I.

    2002-01-01

    Bed rest reduces orthostatic tolerance. Despite decades of study, the cause of this phenomenon remains unclear. In this report we examined hemodynamic and sympathetic nerve responses to graded lower body negative pressure (LBNP) before and after 24 h of bed rest. LBNP allows for baroreceptor disengagement in a graded fashion. We measured heart rate (HR), cardiac output (HR x stroke volume obtained by echo Doppler), and muscle sympathetic nerve activity (MSNA) during a progressive and graded LBNP paradigm. Negative pressure was increased by 10 mmHg every 3 min until presyncope or completion of -60 mmHg. After bed rest, LBNP tolerance was reduced in 11 of 13 subjects (P <.023), HR was greater (P <.002), cardiac output was unchanged, and the ability to augment MSNA at high levels of LBNP was reduced (rate of rise for 30- to 60-mmHg LBNP before bed rest 0.073 bursts x min(-1) x mmHg(-1); after bed rest 0.035 bursts x min(-1) x mmHg(-1); P < 0.016). These findings suggest that 24 h of bed rest reduces sympathetic nerve responses to LBNP.

  14. Iterative solutions of sparse linear systems on systolic arrays. Technical report

    SciTech Connect

    Melhem, R.

    1987-03-01

    The idea of grouping the non-zero elements of a sparse matrix into few strips that are almost parallel is applied to the design of a systolic accelerator for sparse matrix operations. This accelerator is, then, integrated into a complete systolic system for the solution of large sparse linear systems of equations. The design demonstrates that the application of systolic arrays is not limited to regular computations, and that computationally irregular problems may be solved on systolic networks if local storage is provided in each systolic cell for buffering the irregularity in the data movement and for absorbing the irregularity in the computation.

  15. The impact of fertilization on the chicken egg yolk plasma and granule proteome 24 hours post-lay at room temperature: capitalizing on high-pH/low-pH reverse phase chromatography in conjunction with tandem mass tag (TMT) technology.

    PubMed

    Padliya, Neerav D; Qian, Meiqian; Mimi Roy, Sushmita; Chu, Patrick; Zheng, Haiyan; Tess, Alex; Dariani, Maghsoud; Hariri, Robert J

    2015-07-01

    Chicken egg yolk is a rich source of nutrients providing high quality proteins, vitamins, minerals, carotenoids and antioxidants. Chicken egg yolk, recovered from whole egg within 24 hours post-lay has been utilized as a starting material in the preparation of a dietary supplement that has been demonstrated to lead to gains in muscle mass in a human clinical study. Further, an oil derived from chicken egg yolk has been utilized as a topical agent to treat third degree burn injury. The molecular changes that take place in fertilized, chicken egg yolk during the first 24 hours post-lay are not well understood. By studying how the protein composition of egg yolk varies with fertility status, one can utilize this knowledge to develop egg yolk-based products that have been optimized for specific applications. In this study, a direct quantitative comparison was made between the proteome of fertilized chicken egg yolk and the proteome of unfertilized chicken egg yolk, both maintained at 20 °C and analyzed within 24 hours post-lay. Egg yolk proteins from each fertility state were digested with trypsin, labeled with distinct chemical labels (tandem mass tag reagents) and then combined in a 1 : 1 ratio. A TMT-labeled tryptic digest derived from chicken egg yolk proteins (fertilized and unfertilized) was separated using high-pH/low-pH reverse-phase chromatography and analyzed using mass spectrometry. 225 protein identifications were made from this TMT-labeled tryptic digest based on a minimum of 2 unique peptides observed per protein. 9 proteins increased in abundance in fertilized egg yolk relative to unfertilized egg yolk and 9 proteins decreased in abundance in fertilized egg yolk relative to unfertilized egg yolk. Some proteins that increased in abundance in fertilized egg yolk play an important role in angiogenesis (pleiotrophin, histidine rich glycoprotein) and defense against pathogens (mannose-binding lectin, β-defensin 11, serum amyloid P-component, ovostatin

  16. Atrial Fibrillation Ablation in Systolic Dysfunction: Clinical and Echocardiographic Outcomes

    PubMed Central

    Lobo, Tasso Julio; Pachon, Carlos Thiene; Pachon, Jose Carlos; Pachon, Enrique Indalecio; Pachon, Maria Zelia; Pachon, Juan Carlos; Santillana, Tomas Guillermo; Zerpa, Juan Carlos; Albornoz, Remy Nelson; Jatene, Adib Domingos

    2015-01-01

    Background Heart failure and atrial fibrillation (AF) often coexist in a deleterious cycle. Objective To evaluate the clinical and echocardiographic outcomes of patients with ventricular systolic dysfunction and AF treated with radiofrequency (RF) ablation. Methods Patients with ventricular systolic dysfunction [ejection fraction (EF) <50%] and AF refractory to drug therapy underwent stepwise RF ablation in the same session with pulmonary vein isolation, ablation of AF nests and of residual atrial tachycardia, named "background tachycardia". Clinical (NYHA functional class) and echocardiographic (EF, left atrial diameter) data were compared (McNemar test and t test) before and after ablation. Results 31 patients (6 women, 25 men), aged 37 to 77 years (mean, 59.8±10.6), underwent RF ablation. The etiology was mainly idiopathic (19 p, 61%). During a mean follow-up of 20.3±17 months, 24 patients (77%) were in sinus rhythm, 11 (35%) being on amiodarone. Eight patients (26%) underwent more than one procedure (6 underwent 2 procedures, and 2 underwent 3 procedures). Significant NYHA functional class improvement was observed (pre-ablation: 2.23±0.56; postablation: 1.13±0.35; p<0.0001). The echocardiographic outcome also showed significant ventricular function improvement (EF pre: 44.68%±6.02%, post: 59%±13.2%, p=0.0005) and a significant left atrial diameter reduction (pre: 46.61±7.3 mm; post: 43.59±6.6 mm; p=0.026). No major complications occurred. Conclusion Our findings suggest that AF ablation in patients with ventricular systolic dysfunction is a safe and highly effective procedure. Arrhythmia control has a great impact on ventricular function recovery and functional class improvement. PMID:25387404

  17. Frequency-multiplexed and pipelined iterative optical systolic array processors

    NASA Technical Reports Server (NTRS)

    Casasent, D.; Jackson, J.; Neuman, C.

    1983-01-01

    Optical matrix processors using acoustooptic transducers are described, with emphasis on new systolic array architectures using frequency multiplexing in addition to space and time multiplexing. A Kalman filtering application is considered in a case study from which the operations required on such a system can be defined. This also serves as a new and powerful application for iterative optical processors. The importance of pipelining the data flow and the ordering of the operations performed in a specific application of such a system are also noted. Several examples of how to effectively achieve this are included. A new technique for handling bipolar data on such architectures is also described.

  18. Practical issues in implementing roving spares in VLSI systolic arrays

    NASA Technical Reports Server (NTRS)

    Bandekar, Rajendra; Majumdar, Amitava

    1993-01-01

    In this paper we address several unsolved problems in implementing roving spares as a methodology for on-line testing and reconfiguration of systolic arrays. An algorithm for distinguishing between permanent faults and intermittent/transient faults is proposed. A methodology for determining different parameter values for this algorithm is presented. Results characterizing an optimal switching structure are presented. A judicious partitioning of information (for distributed and central processing) allows design of simple switch controllers for implementing roving spares operation as well as reconfiguration in the presence of failures. Testability and self-checking capability is incorporated into these controllers using a few extra gates.

  19. Impact of Stress Reduction Interventions on Hostility and Ambulatory Systolic Blood Pressure in African American Adolescents

    ERIC Educational Resources Information Center

    Wright, Lynda Brown; Gregoski, Mathew J.; Tingen, Martha S.; Barnes, Vernon A.; Treiber, Frank A.

    2011-01-01

    This study examined the impact of breathing awareness meditation (BAM), life skills (LS) training, and health education (HE) interventions on self-reported hostility and 24-hour ambulatory blood pressure (ABP) in 121 African American (AA) ninth graders at increased risk for development of essential hypertension. They were randomly assigned to BAM,…

  20. Target blood pressure for treatment of isolated systolic hypertension in the elderly: valsartan in elderly isolated systolic hypertension study.

    PubMed

    Ogihara, Toshio; Saruta, Takao; Rakugi, Hiromi; Matsuoka, Hiroaki; Shimamoto, Kazuaki; Shimada, Kazuyuki; Imai, Yutaka; Kikuchi, Kenjiro; Ito, Sadayoshi; Eto, Tanenao; Kimura, Genjiro; Imaizumi, Tsutomu; Takishita, Shuichi; Ueshima, Hirotsugu

    2010-08-01

    In this prospective, randomized, open-label, blinded end point study, we aimed to establish whether strict blood pressure control (<140 mm Hg) is superior to moderate blood pressure control (> or =140 mm Hg to <150 mm Hg) in reducing cardiovascular mortality and morbidity in elderly patients with isolated systolic hypertension. We divided 3260 patients aged 70 to 84 years with isolated systolic hypertension (sitting blood pressure 160 to 199 mm Hg) into 2 groups, according to strict or moderate blood pressure treatment. A composite of cardiovascular events was evaluated for > or =2 years. The strict control (1545 patients) and moderate control (1534 patients) groups were well matched (mean age: 76.1 years; mean blood pressure: 169.5/81.5 mm Hg). Median follow-up was 3.07 years. At 3 years, blood pressure reached 136.6/74.8 mm Hg and 142.0/76.5 mm Hg, respectively. The blood pressure difference between the 2 groups was 5.4/1.7 mm Hg. The overall rate of the primary composite end point was 10.6 per 1000 patient-years in the strict control group and 12.0 per 1000 patient-years in the moderate control group (hazard ratio: 0.89; [95% CI: 0.60 to 1.34]; P=0.38). In summary, blood pressure targets of <140 mm Hg are safely achievable in relatively healthy patients > or = 70 years of age with isolated systolic hypertension, although our trial was underpowered to definitively determine whether strict control was superior to less stringent blood pressure targets. PMID:20530299

  1. Systolic algorithms for B-spline patch generation

    SciTech Connect

    Megson, G.M. )

    1991-03-01

    This paper describes a systolic array for constructing the blending functions of B-spline curves and surfaces to be 7k times faster than the equivalent sequential computation. The array requires just 5k inner product cell equivalents, where k - 1 is the maximum degree of the blending function polynomials. This array is then used as a basis for a composite systolic architecture for generating single or multiple points on a B-spline curve or surface. The total hardware requirement is bounded by 5 max (k, l) + 3 (max(m,n) + 1) inner product cells and O(mn) registers, where m and n are the numbers of control points in the two available directions. The hardware can be reduced to 5 max(k, l) + max(m,n) + 1 if each component of a point is generated by separate passes of data through the array. Equations for the array speed-up are given and likely speed-ups for different sized patches considered.

  2. Mathematical modeling of aortic valve dynamics during systole.

    PubMed

    Aboelkassem, Yasser; Savic, Dragana; Campbell, Stuart G

    2015-01-21

    We have derived a mathematical model describing aortic valve dynamics and blood flow during systole. The model presents a realistic coupling between aortic valve dynamics, sinus vortex local pressure, and variations in the systemic vascular resistance. The coupling is introduced by using Hill׳s classical semi-spherical vortex model and an aortic pressure-area compliance constitutive relationship. The effects of introducing aortic sinus eddy vortices and variable systemic vascular resistance on overall valve opening-closing dynamics, left ventricular pressure, aortic pressure, blood flow rate, and aortic orifice area are examined. In addition, the strength of the sinus vortex is coupled explicitly to the valve opening angle, and implicitly to the aortic orifice area in order to predict how vortex strength varies during the four descriptive phases of aortic valve motion (fast-opening, fully-opening, slow-closing, and fast-closing). Our results compare favorably with experimental observations and the model reproduces well-known phenomena corresponding to aortic valve function such as the dicrotic notch and retrograde flow at end systole. By invoking a more complete set of physical phenomena, this new model will enable representation of pathophysiological conditions such as aortic valve stenosis or insufficiency, making it possible to predict their integrated effects on cardiac load and systemic hemodynamics. PMID:25451522

  3. Modeling Pathologies of Diastolic and Systolic Heart Failure.

    PubMed

    Genet, M; Lee, L C; Baillargeon, B; Guccione, J M; Kuhl, E

    2016-01-01

    Chronic heart failure is a medical condition that involves structural and functional changes of the heart and a progressive reduction in cardiac output. Heart failure is classified into two categories: diastolic heart failure, a thickening of the ventricular wall associated with impaired filling; and systolic heart failure, a dilation of the ventricles associated with reduced pump function. In theory, the pathophysiology of heart failure is well understood. In practice, however, heart failure is highly sensitive to cardiac microstructure, geometry, and loading. This makes it virtually impossible to predict the time line of heart failure for a diseased individual. Here we show that computational modeling allows us to integrate knowledge from different scales to create an individualized model for cardiac growth and remodeling during chronic heart failure. Our model naturally connects molecular events of parallel and serial sarcomere deposition with cellular phenomena of myofibrillogenesis and sarcomerogenesis to whole organ function. Our simulations predict chronic alterations in wall thickness, chamber size, and cardiac geometry, which agree favorably with the clinical observations in patients with diastolic and systolic heart failure. In contrast to existing single- or bi-ventricular models, our new four-chamber model can also predict characteristic secondary effects including papillary muscle dislocation, annular dilation, regurgitant flow, and outflow obstruction. Our prototype study suggests that computational modeling provides a patient-specific window into the progression of heart failure with a view towards personalized treatment planning. PMID:26043672

  4. Systolic time intervals after a seven-day orbital flight

    NASA Astrophysics Data System (ADS)

    Groza, P.; Vrâncianu, R.; Lazǎr, M.; Baevski, R. M.; Funtova, V. L.

    Heart rate, systolic time intervals (pre-ejection period, left ventricular ejection time), ejection fraction, stroke volume and QT interval of two cosmonauts (Leonid Popov - L.P. and Dumitru Prunariu - D.P.) were studied before, during, and after an ergometric bicycle exercise test performed before and after the seven-day Soviet-Romanian orbital flight on the Soyuz 40 - Salyut 6 Complex in May 1981. For this purpose one precordial electrocardiogram (ecg) and the ear photodensitogram (den) were recorded stimulaneously. The method used permitted recording even during exercise, Ecg and den signals were stored on magnetic tape, processed in an analogue device and in a digital computer. The data obtained after landing suggest a slight cardiac deconditioning in L.P., demonstrated especially by augmentation of the pre-ejection period, which was unchanged in D.P. corresponding to a sympathoadrenergic hypertonia. The seven-day orbital flight has not produced important cardiovascular changes.

  5. Exaggerated Response of Systolic Blood Pressure to Cycle Ergometer

    PubMed Central

    Kim, Young Joo; Chun, Heaja

    2013-01-01

    Objective The aim of this study is to exam the effects of exercise modes on the systolic blood pressure and rate-pressure product during a gradually increasing exercise load from low to high intensity. Methods Fifteen apparently healthy men aged 19 to 23 performed the graded exercise tests on cycle ergometer (CE) and treadmill (TM). During the low-to-maximal exercises, oxygen uptake (VO2), heart rate (HR), systolic blood pressure (SBP) and rate-pressure product were measured. Results CE had a significantly lower maximum VO2 than TM (CE vs. TM: 48.51±1.30 vs. 55.4±1.19 mL/kg/min; p<0.001). However, CE showed a higher maximum SBP (SBPmax) at the all-out exercise load than TM (CE vs. TM: 170±2.4 vs. 154±1.7 mmHg; p<0.001). During the low-to-maximal intensity increment, the slope of the HR with VO2 was the same as VO2 increased in times of the graded exercise test of CE and TM (CE vs. TM: 2.542±0.100 vs. 2.506±0.087; p=0.26). The slope of increase on SBP accompanied by VO2 increase was significantly higher in CE than in TM (CE vs. TM: 1.669±0.117 vs. 1.179±0.063; p<0.001). Conclusion The SBP response is stronger in CE than in TM during the graded exercise test. Therefore, there is a possibility that CE could induce a greater burden on workloads to cardiovascular system in humans than TM. PMID:23869334

  6. Efficient bit-level, word-level, and block-level systolic arrays for matrix-matrix multiplication

    SciTech Connect

    De Groot, A.J.; Parker, S.R.; Johansson, E.M.

    1988-02-01

    This paper investigates the mapping of matrix-matrix multiplication onto bit level, word level and block level systolic arrays. Highly efficient and regular bit level, word level and block level systolic arrays are described. Efficiencies of many block level and word level systolic arrays reported in this paper approach 100/percent/, three times the efficiencies of systolic arrays reported previously. Bit level systolic arrays reported in this paper require less computation time than do bit level systolic arrays reported previously and, for special matrices, require less cells. Execution times of block level systolic algorithms on sixty-four-element multiprocessor agree with theory.

  7. A relative difference in systolic blood pressure between arms by synchronal measurement and conventional cardiovascular risk factors are associated with the severity of coronary atherosclerosis.

    PubMed

    Yamamoto, Tomohiko; Miura, Shin-Ichiro; Suematsu, Yasunori; Kuwano, Takashi; Sugihara, Makoto; Ike, Amane; Iwata, Atsushi; Nishikawa, Hiroaki; Saku, Keijiro

    2016-06-01

    It is not known the relationships between a difference in systolic blood pressure (SBP) or diastolic BP (DBP) between arms by synchronal measurement and the presence of coronary artery disease (CAD), and between a difference in BP between arms and the severity of coronary atherosclerosis. We enrolled 425 consecutive patients (M/F = 286/139, 67 ± 13 year) who were admitted to our University Hospital and in whom we could measure the absolute (|rt. BP - lt. BP|) and relative (rt. BP - lt. BP) differences in SBP and DBP using a nico PS-501(®) (Parama-Tech). We divided all patients into those who did and did not have CAD. The relative differences in SBP between arms in patients with CAD were significantly lower than those in patients without CAD. However, the relative difference in SBP between arms was not a predictor of the presence of CAD. We also divided 267 patients who underwent coronary angiography into tertiles according to the Gensini score (low, middle, and high score groups). Interestingly, the middle + high score groups showed significantly lower relative differences in SBP between arms than the low score group. The mean Korotkoff sound graph in the middle + high Gensini score group was significantly higher than that in the low Gensini score group. Among conventional cardiovascular risk factors and nico parameters, the relative difference in SBP between arms in addition to the risk factors (age, gender, body mass index, hypertension, dyslipidemia, and diabetes mellitus) was associated with the score by a logistic regression analysis. In conclusion, the relative difference in SBP between arms as well as conventional risk factors may be associated with the severity of coronary arteriosclerosis. PMID:25921917

  8. On efficient simulations of systolic arrays by random-access machines

    SciTech Connect

    Ibarra, O.H.; Palis, M.A.

    1987-04-01

    The authors give efficient simulations of systolic arrays by unit-cost random-access machines (RAM's). For example, they show that a one-dimensional systolic array operating in linear time can be simulated by a RAM in O(n/sup 2//log/sup 2/n) time. For the case of a two-dimensional systolic array, the simulation time is O(n/sup 3//log/sup 3/2/n).

  9. Short and Long-Term Effect of Carotid Artery Stenting on Arterial Blood Pressure Measured through Ambulatory Blood Pressure Monitoring

    PubMed Central

    Köklü, Erkan; Yüksel, İsa Öner; Arslan, Şakir; Bayar, Nermin; Köklü, Fatma; Çay, Serkan; Çağırcı, Göksel; Küçükseymen, Selçuk; Kuş, Görkem

    2016-01-01

    Background The aim of this study was to assess the short and long-term effects of carotid artery stenting (CAS) procedure on blood pressure (BP) through ambulatory BP monitoring. Methods One hundred fifty three patients who underwent CAS for primary or secondary protection from December 2010 to September 2013 were enrolled to our study. The BP levels of total of 123 patients were monitored for 1 year. Thereafter, the pre-procedure levels of BP were compared with BP levels at the 24-hour and the first year intervals after the procedure. Results Systolic and diastolic BP levels at the 24-hour and the first year intervals after CAS were significantly lower than the pre-procedure BP levels. The mean 24-hour systolic BP was 113 ± 13 mmHg and diastolic BP was 63 ± 8 mmHg, both of which were significantly lower (p < 0.001 and p < 0.001 respectively), while the pre-procedure mean systolic BP was 133 ± 10 mmHg and the mean diastolic BP was 75 ± 9 mmHg. Moreover, the mean first-year systolic BP was 125 ± 10 mmHg with a decline of 8 ± 8 mmHg and mean diastolic BP was 71 ± 8 mmHg with a decline of 4 ± 7 mmHg, both of which were again significantly lower compared to the pre-procedure levels (p < 0.001 and p < 0.001 respectively). Conclusions The results of our study suggested that systolic and diastolic BP levels diminished after CAS. Additionally, BP reduction continued even 1 year after the CAS. PMID:27274176

  10. Clinical Practice Guideline for the Treatment of Intrinsic Circadian Rhythm Sleep-Wake Disorders: Advanced Sleep-Wake Phase Disorder (ASWPD), Delayed Sleep-Wake Phase Disorder (DSWPD), Non-24-Hour Sleep-Wake Rhythm Disorder (N24SWD), and Irregular Sleep-Wake Rhythm Disorder (ISWRD). An Update for 2015

    PubMed Central

    Auger, R. Robert; Burgess, Helen J.; Emens, Jonathan S.; Deriy, Ludmila V.; Thomas, Sherene M.; Sharkey, Katherine M.

    2015-01-01

    A systematic literature review and meta-analyses (where appropriate) were performed and the GRADE approach was used to update the previous American Academy of Sleep Medicine Practice Parameters on the treatment of intrinsic circadian rhythm sleep-wake disorders. Available data allowed for positive endorsement (at a second-tier degree of confidence) of strategically timed melatonin (for the treatment of DSWPD, blind adults with N24SWD, and children/ adolescents with ISWRD and comorbid neurological disorders), and light therapy with or without accompanying behavioral interventions (adults with ASWPD, children/adolescents with DSWPD, and elderly with dementia). Recommendations against the use of melatonin and discrete sleep-promoting medications are provided for demented elderly patients, at a second- and first-tier degree of confidence, respectively. No recommendations were provided for remaining treatments/ populations, due to either insufficient or absent data. Areas where further research is needed are discussed. Citation: Auger RR, Burgess HJ, Emens JS, Deriy LV, Thomas SM, Sharkey KM. Clinical practice guideline for the treatment of intrinsic circadian rhythm sleep-wake disorders: advanced sleep-wake phase disorder (ASWPD), delayed sleep-wake phase disorder (DSWPD), non-24-hour sleep-wake rhythm disorder (N24SWD), and irregular sleep-wake rhythm disorder (ISWRD). An update for 2015. J Clin Sleep Med 2015;11(10):1199–1236. PMID:26414986

  11. SPRINT: The Systolic Processor with a Reconfigurable Interconnection Network of Transputers

    SciTech Connect

    De Groot, A.J.; Johansson, E.M.; Fitch, J.P.; Grant, C.W.; Parker, S.R.

    1987-05-01

    The Systolic Processor with a Reconfigurable Interconnection Network of Transputers (SPRINT) is a sixty-four-processor multiprocessor developed at Lawrence Livermore National Laboratory for experimentally evaluating systolic algorithms and architectures. This paper describes the architecture of the SPRINT and several algorithms which have been executed on it.

  12. Oscillometric measurement of systolic and diastolic blood pressures validated in a physiologic mathematical model

    PubMed Central

    2012-01-01

    Background The oscillometric method of measuring blood pressure with an automated cuff yields valid estimates of mean pressure but questionable estimates of systolic and diastolic pressures. Existing algorithms are sensitive to differences in pulse pressure and artery stiffness. Some are closely guarded trade secrets. Accurate extraction of systolic and diastolic pressures from the envelope of cuff pressure oscillations remains an open problem in biomedical engineering. Methods A new analysis of relevant anatomy, physiology and physics reveals the mechanisms underlying the production of cuff pressure oscillations as well as a way to extract systolic and diastolic pressures from the envelope of oscillations in any individual subject. Stiffness characteristics of the compressed artery segment can be extracted from the envelope shape to create an individualized mathematical model. The model is tested with a matrix of possible systolic and diastolic pressure values, and the minimum least squares difference between observed and predicted envelope functions indicates the best fit choices of systolic and diastolic pressure within the test matrix. Results The model reproduces realistic cuff pressure oscillations. The regression procedure extracts systolic and diastolic pressures accurately in the face of varying pulse pressure and arterial stiffness. The root mean squared error in extracted systolic and diastolic pressures over a range of challenging test scenarios is 0.3 mmHg. Conclusions A new algorithm based on physics and physiology allows accurate extraction of systolic and diastolic pressures from cuff pressure oscillations in a way that can be validated, criticized, and updated in the public domain. PMID:22913792

  13. Systolic arterial pressure determination by a new pulse monitor technique.

    PubMed

    Wong, D T; Volgyesi, G A; Bissonnette, B

    1992-07-01

    The Doppler ultrasound (DUS) technique is a widely accepted non-invasive technique to estimate systolic blood pressure (SBP) accurately in paediatric patients. The DUS has a number of limitations. A new pulse monitor, Mr Pulse (MP), operating on the principle of a finger plethysmograph, was developed to offer an alternative technique to estimate SBP. From 104 paired SBP measurements taken in 16 paediatric patients undergoing general anaesthesia, SBP determined by the MP technique correlated closely with that by the standard DUS technique (r2 = 0.98). Analysis of degree of agreement performed indicated that there was good agreement between SBP obtained by the MP and the DUS techniques. The mean +/- standard deviation of differences in paired SBP values between the two measurement techniques was 0.55 +/- 3.59 mmHg. Mr Pulse is as accurate as the DUS technique in estimating SBP and has the advantage of less critical sensor positioning as it is not subject to electrical interference. It has no electrical hazard. PMID:1643685

  14. Detection of systolic ejection click using time growing neural network.

    PubMed

    Gharehbaghi, Arash; Dutoit, Thierry; Ask, Per; Sörnmo, Leif

    2014-04-01

    In this paper, we present a novel neural network for classification of short-duration heart sounds: the time growing neural network (TGNN). The input to the network is the spectral power in adjacent frequency bands as computed in time windows of growing length. Children with heart systolic ejection click (SEC) and normal children are the two groups subjected to analysis. The performance of the TGNN is compared to that of a time delay neural network (TDNN) and a multi-layer perceptron (MLP), using training and test datasets of similar sizes with a total of 614 normal and abnormal cardiac cycles. From the test dataset, the classification rate/sensitivity is found to be 97.0%/98.1% for the TGNN, 85.1%/76.4% for the TDNN, and 92.7%/85.7% for the MLP. The results show that the TGNN performs better than do TDNN and MLP when frequency band power is used as classifier input. The performance of TGNN is also found to exhibit better immunity to noise. PMID:24613501

  15. Nighttime Systolic Blood-Pressure Load Is Correlated with Target-Organ Damage Independent of Ambulatory Blood-Pressure Level in Patients with Non-Diabetic Chronic Kidney Disease

    PubMed Central

    Deng, Wenjie; Gong, Wenyu; Liu, Xun; Ye, Zengchun; Peng, Hui; Lou, Tanqi

    2015-01-01

    Background The impacts of blood pressure (BP) load on target-organ damage in patients with chronic kidney disease (CKD) are largely unclear. We examined whether BP load is correlated with target-organ damage (TOD) in Chinese CKD patients independent of BP level. Methods We recruited 1219 CKD patients admitted to our hospital division in this cross-sectional study. The TOD were measured by estimated glomerular filtration rate (eGFR), proteinuria, left ventricular mass index (LVMI) and carotid intima-media thickness (cIMT) in this study. Univariate and multivariate linear analyses were used to evaluate the relationship between systolic blood pressure (SBP) load, diastolic blood pressure (DBP) load and these renal, cardiovascular parameters. Results In multivariable-adjusted models, BP load and ambulatory BP levels both independently correlated with LVMI, eGFR and proteinuria in all groups of CKD patients (p<0.05), 24-h SBP correlated with cIMT only in non-diabetic CKD patients without hypertension (p<0.05), while nighttime SBP load was associated with cIMT only in non-diabetic CKD patients (p<0.05). Furthermore, nighttime SBP load additionally increased coefficient of determination (R2) and correlated with LVMI, proteinuria in non-diabetic CKD patients without hypertension (R2 = 0.034, P<0.001 and R2 = 0.012, P = 0.006 respectively) and LVMI, cIMT, eGFR in non-diabetic CKD patients with hypertension (R2>0.008, P<0.05) in multivariable-adjusted model which already including the 24-h BP. BP load did not refine this correlation based on the 24-h BP level in diabetic CKD patients. Conclusion Night-time SBP load was correlated with TOD in patients with non-diabetic chronic kidney disease independent of BP level. PMID:26186336

  16. Validation of the A&D BP UB-543 wrist device for home blood pressure measurement according to the European Society of Hypertension International Protocol revision 2010.

    PubMed

    Fania, Claudio; Benetti, Elisabetta; Palatini, Paolo

    2015-08-01

    The aim of this study was to determine the accuracy of the A&D BP UB-543 wrist device for home blood pressure (BP) measurement according to the International Protocol of the European Society of Hypertension. The A&D BP UB-543 monitor is provided with a correct position guidance (CPG) indicator that ensures the correct placement of the wrist at the heart level. Device evaluation was carried out in 33 patients with the CPG indicator on. The mean age of the patients was 53.1±16.4 years, the mean systolic BP was 141.8±25.1 mmHg (range 84 : 196), the mean diastolic BP was 88.2±14.5 mmHg (range 34 : 132), the mean arm circumference was 29.0±3.6 cm (range 21 : 38), and the mean wrist circumference was 17.5±1.4 cm (range 15 : 20). The protocol requirements were followed precisely. The device passed all requirements, fulfilling the standards of the protocol. On average, the device overestimated the systolic BP by 1.1±2.9 mmHg and underestimated diastolic BP by 0.1±3.0 mmHg. These data show that the A&D BP UB-543 wrist device used correctly with the CPG indicator on met the requirements for validation by the International Protocol and can be recommended for clinical use in the adult population. PMID:25768063

  17. Abstract specification of synchronous data types for VLSI and proving the correctness of systolic network implementations

    SciTech Connect

    Probst, D.K.; Li, H.F.

    1988-06-01

    The authors present a combined methodology for specifying abstract synchronous data types and proving the correctness of systolic network implementations. 1) The authors show that an extension of the Parnas trace method of specifying software modules containing distinct access programs yields a natural method of specifying abstract synchronous data types which possess distinct access operators and are intended for implementation in VLSI. 2). They present associated systematic proof techniques and establish the correctness of several novel systolic network implementations of familiar data types. In so far as these specifications refer to the ongoing, externally visible behavior of (abstract) synchronous objects rather than the instantaneous internal configurations of (concrete, implementing) synchronous systems, the methodology appears to be naturally suited to systolic network implementations with their associated rippling of control flow and data flow. The important distinction between systolic control-flow networks and systolic data-flow networks is also presented.

  18. Two-level pipelined systolic array for multi-dimensional convolution

    SciTech Connect

    Kung, H.T.; Ruane, L.M.; Yen, D.W.L.

    1982-11-01

    This paper describes a systolic array for the computation of n-dimensional (n-D) convolutions of any positive integer n. Systolic systems usually achieve high performance by allowing computations to be pipelined over a large array of processing elements. To achieve even higher performance, the systolic array of this paper utilizes a second level of pipelining by allowing the processing elements themselves to be pipelined to an arbitrary degree. Moreover, it is shown that as far as orders of magnitude are concerned, the total amount of memory required by the systolic array is no more than that needed by any convolution device that reads in each input data item only once. Thus if only schemes that use the minimum-possible I/O are considered, the systolic array is not only high performance, but also optimal in terms of the amount of required memory.

  19. Wafer-scale integration and two-level pipelined implementations of systolic arrays

    SciTech Connect

    Kung, H.T.; Lam, M.S.

    1984-08-01

    For problems that have been solved exclusively by systolic arrays with feedback cycles, this paper introduces a new class of systolic algorithms based on a ring architecture. These systolic rings have the property that the throughput degrades gracefully as the number of failed cells in the rings increases. Furthermore, as a byproduct of the ring architecture approach, the authors have derived several new systolic algorithms which require only one-third to one-half of the cells used in previous designs while achieving the same throughput. They have shown that the two-level pipelining problem in systolic arrays are solved by the same techniques used to solve the fault-tolerance problem. An important task left for the future is the development of software to solve both problems automatically.

  20. Fault-tolerance and two-level pipelining in VLSI systolic arrays

    SciTech Connect

    Kung, H.T.; Lam, M.S.

    1984-01-01

    The authors address two important issues in systolic array designs: fault-tolerance and two-level pipelining. The proposed systolic fault-tolerant scheme maintains the original data flow pattern by bypassing defective cells with a few registers. As a result, many of the desirable properties of systolic arrays (such as local and regular communication between cells) are preserved. Two-level pipelining refers to the use of pipelined functional units in the implementation of systolic cells. The authors paper addresses the problem of efficiently utilizing pipelined units to increase the overall system throughput. They show that both of these problems can be reduced to the same mathematical problem of incorporating extra delays on certain data paths in originally correct systolic designs. They introduce the mathematical notion of a cut which enables them to handle this problem effectively. The results obtained by applying the techniques described are encouraging. When applied to systolic arrays without feedback cycles, the arrays can tolerate large numbers of failures (with the addition of very little hardware) while maintaining the original throughput. Furthermore, all of the pipeline stages in the cells can be kept fully utilized through the addition of a small number of delay registers. However, adding delays to systolic arrays with cycles typically induces a significant decrease in throughput. In response to this, they have derived a new class of systolic algorithms in which the data cycle around a ring of processing cells. The systolic ring architecture has the property that its performance degrades gracefully as cells fail. Using the cut theory for arrays without feedback and the ring architecture approach for those with feedback, they have effective fault-tolerant and two-level pipelining schemes for most systolic arrays. 24 references.

  1. Electronic states of BP, BP +, BP -, B 2P 2, B2P2- and B2P2+

    NASA Astrophysics Data System (ADS)

    Linguerri, Roberto; Komiha, Najia; Oswald, Rainer; Mitrushchenkov, Alexander; Rosmus, Pavel

    2008-05-01

    Using augmented sextuple zeta basis sets and internally contracted multireference configuration interaction (MRCI) wavefunctions, potential energy, electric dipole and transition moments have been computed for the X 3Π, a 1Σ +, b 1Π and A 3Σ - states of BP, X 2Σ + and A 2Π states of BP - and X 4Σ - and A 4Π states of BP +. From these data spectroscopic constants, radiative transition probabilities and photoelectron spectra of BP - and BP have been evaluated. The non-vanishing spin-orbit coupling elements between the four low lying triplet and singlet states of the neutral BP have also been calculated from MRCI wavefunctions. The treatment of the corresponding perturbations in the manifold of dense rovibrational states in the three lowest states would require a precise knowledge of the electronic excitation energies. Our best singlet-triplet separations (X-a) are calculated to be 2412 cm -1 (MRCI) and 2482 cm -1 (restricted coupled cluster with perturbative triples (RCCSD(T))) with an estimated error bound of about ±200 cm -1. All three states have long radiative lifetimes with cascading among the rovibrational levels of different states. The ionization energy IE e of BP is calculated to be 9.22 eV (MRCI) and 9.48 eV (RCCSD(T)), the electron affinity EA e 2.51 eV (MRCI) and 2.74 eV (RCCSD(T)). The photoelectron spectra of BP and BP - have been obtained from the Franck-Condon factors of the MRCI potentials. For the UV spectroscopy the dipole allowed radiative transition probabilities are given for A 3Σ - ↔ X 3Π, b 1Π ↔ a 1Σ + of BP, A 2Π ↔ X 2Σ + of BP - and A 4Π ↔ X 4Σ - of BP +. The ionization energy IE e of B 2P 2 of 8.71 eV and the electron affinity EA e of 2.34 eV have been calculated by the RCCSD(T)/aVQZ approach. Also the harmonic vibrational wavenumbers for the electronic ground states of the ions B2P2+ and B2P2- are given.

  2. Validation of the A&D BP UA-651 device with a wide-range cuff for home blood pressure measurement according to the European Society of Hypertension International Protocol revision 2010.

    PubMed

    Benetti, Elisabetta; Fania, Claudio; Palatini, Paolo

    2015-06-01

    The aim of this study was to determine the accuracy of the A&D BP UA-651 device coupled to a wide-range cuff for home blood pressure (BP) measurement according to the International Protocol of the European Society of Hypertension. The device was evaluated in 33 patients. The mean age of the patients was 56.5±15.1 years. The mean systolic BP was 144.3±23.8 mmHg (range 88 : 196), the mean diastolic BP was 87.5±15.8 mmHg (range 38 : 132), and the mean arm circumference was 29.0±3.4 cm (range 22 : 36). The protocol requirements were followed precisely. The device passed all requirements, fulfilling the standards of the protocol. On average, the device overestimated the systolic BP by 0.7±3.4 mmHg and underestimated the diastolic BP by 0.8±3.6 mmHg. The measurement error was unrelated to the patient's arm circumference. These data show that the A&D BP UA-651 device coupled to a wide-range cuff fulfilled the requirements for validation by the International Protocol over a wide range of arm circumferences and can be recommended for clinical use in the adult population. PMID:25536400

  3. Assessment of right ventricular systolic function by tissue Doppler echocardiography.

    PubMed

    Kjærgaard, Jesper

    2012-03-01

    -massive pulmonary embolism quantifies degree of RV dysfunction, and supports the existence of the McConnell sign of mid-ventricular RV dysfunction. Echocardiographic signs of RV dysfunction are present if > 25% of the pulmonary vascular bed is obstructed. However, Tissue Doppler echocardiography and deformation analysis has no independent value over other clinical and quantitative echocardiographic measures of RV size, pressure and function in these patients [IV and V]. Regional deformation of the RV free wall has significant prognostic importance in a population suspected of first non-massive pulmonary embolism, and is significantly associated with adverse events in patients with proven pulmonary embolism, however, it does not add to the information gained from other quantitative echocardiographic measures of LV and RV function and pressure [VI]. Changes in tissue Doppler based measures of RV systolic function can be used to monitor the effect of selective vasodilation by phosphodiestares-5 inhibition in hypoxic pulmonary hypertension and exercise in normal individuals. Phosphodiestares-5 inhibition by sildenafil may predominantly be effective during hypoxia in resting conditions, and may improve the blunted response in RV contractility seen with exercise in hypoxia [VII]. Reduced RV free wall deformation can be quantified by tissue Doppler echocardiography in patients with confirmed Arrhythmogenic Right Ventricular Cardiomyopathy, but the clinical application of the technique may be limited by considerable overlap with normal values [VIII]. Acute RV volume loading in free pulmonary regurgitation is associated with abrupt geometric changes in the RV structure including significant dilatation, but is well tolerated with only mild reduction in measures of global RV systolic function as estimated by 2D echocardiography in an experimental animal model. Regional RV myocardial function is also only mildly reduced. Also no differences in global or regional RV function can be observed

  4. Severe systolic hypertension and the search for safer motherhood.

    PubMed

    Martin, James N

    2016-03-01

    Timely and appropriate response to severe hypertension during gestation is an important component of quality, safe care for pregnant or puerperal mothers regardless of causation. The reduction of severe maternal morbidity and maternal mortality in the hypertensive mother is clearly enhanced by the addition of standard protocols for provider response to severe hypertension, particularly severe systolic hypertension. The program developed in New York State via the Safe Motherhood Initiative promotes the implementation of unit-specific safety bundles, especially one that is focused upon a standardized approach to handling the obstetric emergency of severe hypertension usually associated with preeclampsia/eclampsia. The comprehensive preeclampsia/eclampsia safety bundle as summarized by Drs. Moroz and colleagues is reviewed especially from the perspective of its focus on the timely and specific responses for health care providers to make when severe hypertension is detected in the pregnant patient. Evidence-based guidance to practice considerations and clinical care of patients with preeclampsia/eclampsia is embedded within the program outlined for New York State by Moroz and her District II ACOG colleagues. There is a central focus on timely and appropriate antepartum/postpartum management of severe hypertension, a core concept to lessen maternal risk for cerebral hemorrhage. Ten considerations for further integration into the New York program are suggested. Beyond blood pressure control, there is a need for systematic review of interventions and outcomes over time, attention to possible future variations of the protocol for racial/ethnic patient groups at highest risk for maternal morbidity and mortality, and the identification of biomarker(s) that further specify and quantify risk to the maternal brain and other organ systems when severe hypertension develops. Safer motherhood will happen when evidence for best practice is integrated into systems of care for all

  5. Effect of Left Ventricular Systolic Dysfunction on Response to Warfarin.

    PubMed

    Ather, Sameer; Shendre, Aditi; Beasley, T Mark; Brown, Todd; Hill, Charles E; Prabhu, Sumanth D; Limdi, Nita A

    2016-07-15

    Candidates for chronic warfarin therapy often have co-morbid conditions, such as heart failure, with reduced left ventricular ejection fraction. Previous reports have demonstrated an increased risk of over-anticoagulation due to reduced warfarin dose requirement in patients with decompensated heart failure. However, the influence of left ventricular systolic dysfunction (LVSD), defined as left ventricular ejection fraction <40%, on warfarin response has not been evaluated. Here, we assess the influence of LVSD on warfarin dose, anticoagulation control (percent time in target range), and risk of over-anticoagulation (international normalized ratio >4) and major hemorrhage. Of the 1,354 patients included in this prospective cohort study, 214 patients (16%) had LVSD. Patients with LVSD required 11% lower warfarin dose compared with those without LVSD (p <0.001) using multivariate linear regression analyses. Using multivariate Cox proportional hazards model, patients with LVSD experienced similar levels of anticoagulation control (percent time in target range: 51% vs 53% p = 0.15), risk of over-anticoagulation (international normalized ratio >4; hazard ratio 1.01, 95% confidence interval 0.82 to 1.25; p = 0.91), and risk of major hemorrhage (hazard ratio 1.11; 95% confidence interval 0.70 to 1.74; p = 0.66). Addition of LVSD variable in the model increased the variability explained from 35% to 36% for warfarin dose prediction. In conclusion, our results demonstrate that patients with LVSD require lower doses of warfarin. Whether warfarin dosing algorithms incorporating LVSD in determining initial doses improves outcomes needs to be evaluated. PMID:27241839

  6. Use of Inotropic Agents in Treatment of Systolic Heart Failure

    PubMed Central

    Tariq, Sohaib; Aronow, Wilbert S.

    2015-01-01

    The most common use of inotropes is among hospitalized patients with acute decompensated heart failure, with reduced left ventricular ejection fraction and with signs of end-organ dysfunction in the setting of a low cardiac output. Inotropes can be used in patients with severe systolic heart failure awaiting heart transplant to maintain hemodynamic stability or as a bridge to decision. In cases where patients are unable to be weaned off inotropes, these agents can be used until a definite or escalated supportive therapy is planned, which can include coronary revascularization or mechanical circulatory support (intra-aortic balloon pump, extracorporeal membrane oxygenation, impella, left ventricular assist device, etc.). Use of inotropic drugs is associated with risks and adverse events. This review will discuss the use of the inotropes digoxin, dopamine, dobutamine, norepinephrine, milrinone, levosimendan, and omecamtiv mecarbil. Long-term inotropic therapy should be offered in selected patients. A detailed conversation with the patient and family shall be held, including a discussion on the risks and benefits of use of inotropes. Chronic heart failure patients awaiting heart transplants are candidates for intravenous inotropic support until the donor heart becomes available. This helps to maintain hemodynamic stability and keep the fluid status and pulmonary pressures optimized prior to the surgery. On the other hand, in patients with severe heart failure who are not candidates for advanced heart failure therapies, such as transplant and mechanical circulatory support, inotropic agents can be used for palliative therapy. Inotropes can help reduce frequency of hospitalizations and improve symptoms in these patients. PMID:26690127

  7. BP: synthesis and properties of boron phosphide

    NASA Astrophysics Data System (ADS)

    Woo, Katherine; Lee, Kathleen; Kovnir, Kirill

    2016-07-01

    Cubic boron phosphide, BP, is notorious for its difficult synthesis, thus preventing it from being a widely used material in spite of having numerous favorable technological properties. In the current work, three different methods of synthesis are developed and compared: from the high temperature reaction of elements, Sn flux assisted synthesis, and a solid state metathesis reaction. Structural and optical properties of the products synthesized from the three methods were thoroughly characterized. Solid state metathesis is shown to be the cleanest and most efficient method in terms of reaction temperature and time. Synthesis by Sn flux resulted in a novel Sn-doped BP compound. Undoped BP samples exhibit an optical bandgap of ∼2.2 eV while Sn-doped BP exhibits a significantly smaller bandgap of 1.74 eV. All synthesized samples show high stability in concentrated hydrochloric acid, saturated sodium hydroxide solutions, and fresh aqua regia.

  8. Brachial-to-radial systolic blood pressure amplification in patients with type 2 diabetes mellitus.

    PubMed

    Climie, R E D; Picone, D S; Keske, M A; Sharman, J E

    2016-06-01

    Brachial-to-radial-systolic blood pressure amplification (Bra-Rad-SBPAmp) can affect central SBP estimated by radial tonometry. Patients with type 2 diabetes mellitus (T2DM) have vascular irregularities that may alter Bra-Rad-SBPAmp. By comparing T2DM with non-diabetic controls, we aimed to determine the (1) magnitude of Bra-Rad-SBPAmp; (2) haemodynamic factors related to Bra-Rad-SBPAmp; and (3) effect of Bra-Rad-SBPAmp on estimated central SBP. Twenty T2DM (64±8 years) and 20 non-diabetic controls (60±8 years; 50% male both) underwent simultaneous cuff deflation and two-dimensional ultrasound imaging of the brachial and radial arteries. The first Korotkoff sound (denoting SBP) was identified from the first inflection point of Doppler flow during cuff deflation. Bra-Rad-SBPAmp was calculated by radial minus brachial SBP. Upper limb and systemic haemodynamics were recorded by tonometry and ultrasound. Radial SBP was higher than brachial SBP for T2DM (136±19 vs 127±17 mm Hg; P<0.001) and non-diabetic controls (135±12 vs 121±11 mm Hg; P<0.001), but Bra-Rad-SBPAmp was significantly lower in T2DM (9±8 vs 14±7 mm Hg; P=0.042). The product of brachial mean flow velocity × brachial diameter was inversely and independently correlated with Bra-Rad-SBPAmp in T2DM (β=-0.033 95% confidence interval -0.063 to -0.004, P=0.030). When radial waveforms were calibrated using radial, compared with brachial SBP, central SBP was significantly higher in both groups (T2DM, 116±13 vs 125±15 mm Hg; and controls, 112±10 vs 124±11 mm Hg; P<0.001 both) and there was a significant increase in the number of participants classified with 'central hypertension' (SBP⩾130 mm Hg; P=0.004). Compared with non-diabetic controls, Bra-Rad-SBPAmp is significantly lower in T2DM. Regardless of disease status, radial SBP is higher than brachial SBP and this results in underestimation of central SBP using brachial-BP-calibrated radial tonometry. PMID:26446391

  9. On the design of fault-tolerant two-dimensional systolic arrays for yield enhancement

    SciTech Connect

    Kim, J.H.; Reddy, S.M.

    1989-04-01

    The continuing growth of interest in systolic arrays poses the problem of ensuring an acceptable yield. In this paper, the authors propose a unified approach to the design of fault-tolerant systolic arrays incorporating design for testability, a testing scheme, a reconfiguration algorithm, time complexity analysis of the proposed reconfiguration algorithm, and yield analysis. A main feature of the proposed designs is that multiple PE's in a 2-D array can be tested simultaneously, thus reducing the testing time significantly. Another feature is that with introduction of delay registers, the proposed reconfiguration algorithm reconfigures a faulty 2-D systolic array into a fault-free array without reducing throughput. The overall aim of this paper is to provide a design for a 2-D systolic array that produces high yield in VLSI/WSI implementations.

  10. Unified approach to the analysis and synthesis of systolic arrays. Master's thesis

    SciTech Connect

    Hornick, S.W.

    1985-04-01

    This thesis takes the first steps toward the development of a theoretical framework to unify the analysis and synthesis of systolic networks. A class of transformations on systolic networks is described that alter the topology of a network while preserving the timing of its computations. These transformations may be used to demonstrate the equivalence of two existing systolic designs or to obtain a new design from an existing one, according to particular design specifications. The model of a systolic network is presented, and the parameters are identified that are used to characterize one. Next, the author proves the correctness of two types of transformations on these parameters. He shows how these transformations can account for different processor types and multiple-processor states. Finally, he demonstrates these transformations and characterizes those that avoid the phenomenon of crossing.

  11. Relationship of blood lead to systolic blood pressure in a longitudinal study of policemen

    SciTech Connect

    Weiss, S.T.; Munoz, A.; Stein, A.; Sparrow, D.; Speizer, F.E.

    1988-06-01

    We examined the relationship of blood lead level to systolic and diastolic blood pressure in a longitudinal study of 89 Boston, MA, policemen. At the second examination blood lead level and blood pressure were measured in triplicate. Blood pressure measurements were taken in a similar fashion in years 3, 4, and 5. Multivariate analysis using a first-order autoregressive model revealed that after adjusting for previous systolic blood pressure, body mass index, age, and cigarette smoking, an elevated blood lead level was a significant predictor of subsequent systolic blood pressure. Bootstrap simulations of these models provided supporting evidence for the observed association. These data suggest that blood lead level can influence systolic blood pressure even within the normal range.

  12. A simple versatile method for measuring tail cuff systolic blood pressure in conscious rats.

    PubMed

    Widdop, R E; Li, X C

    1997-09-01

    1. The non-invasive measurement of tail cuff systolic blood pressure in conscious rats is routinely used in long-term cardiovascular studies. There are a number of commercially available tail cuff systems, however, these apparatus are generally expensive and are dedicated for single-task operations. In the present study, a simple method for measuring systolic blood pressure, which requires only minor modifications to the existing hardware found in most cardiovascular laboratories, is described. 2. Systolic blood pressure measurements were made in the conventional manner by determining the systolic blood pressure which coincided with the restoration of the caudal artery pulse. This was achieved by using an inexpensive piezo-electric pulse transducer to detect the pulse, and this was coupled to a standard data-acquisition system (MacLab, ADInstruments) normally set up to record blood pressure. This method was compared with another established tail cuff method, as well as with direct intra-arterial recordings. 3. It was found that the results obtained using both tail cuff systems were in good agreement when systolic blood pressure was measured in Wistar-Kyoto rats and spontaneously hypertensive rats. In addition, systolic blood pressure was measured over 4 weeks in 2K1C rats and sham-operated rats, with both tail cuff methods producing similar results, which were not significantly different from direct intra-arterial recordings in the same animals. 4. Thus, in the present study, with only minor modifications, the same equipment was used for both direct and indirect determinations of systolic blood pressure. This situation differs from other conventional tail cuff systems since these items are designed for a single purpose. Therefore, the current method using piezo-electric sensor/MacLab-technology should be viewed as a relatively simple, flexible and cheap alternative method to measure tail cuff systolic blood pressure in conscious rats. PMID:9337632

  13. Top-down designs of instruction systolic arrays for polynomial interpolation and evaluation

    SciTech Connect

    Schroder, H. )

    1989-06-01

    This paper describes the application of a new parallel architecture-instruction systolic array (ISA)-for the interpolation and evaluation of polynomials using a linear array of processors. It also demonstrates a systemic top-down design of instruction systolic arrays. The periods of the resulting algorithms are O(n) for interpolation and O(1)for evaluation, where n is the degree of the polynomial.

  14. Hearts: a dialect of the Poker programming environment specialized to systolic computation. Technical report

    SciTech Connect

    Snyder, L.

    1986-10-01

    The design of a parallel programming environment specialized to systolic computation is proposed. The system, called Hearts, is a dialect of the Poker parallel-programming environment. The key feature of Hearts that enables it to be a convenient and efficacious facility for writing systolic programs is a novel concept of program that is graphical rather than textual. The use of this program form is illustrated in a full example of the Kung-Leiserson matrix-product algorithm.

  15. Lower Intraprocedural Systolic Blood Pressure Predicts Good Outcome in Patients Undergoing Endovascular Therapy for Acute Ischemic Stroke

    PubMed Central

    John, Seby; Hazaa, Walaa; Uchino, Ken; Toth, Gabor; Bain, Mark; Thebo, Umera; Hussain, Muhammad S.

    2016-01-01

    Background It is unknown if intraprocedural blood pressure (BP) influences clinical outcomes and what BP parameter best predicts outcomes in acute ischemic stroke (AIS) patients who undergo intra-arterial therapy (IAT) for emergent large vessel occlusion. Methods We retrospectively reviewed 147 patients who underwent IAT for anterior circulation AIS from January 2008 to December 2012 at our institution. Baseline demographics, stroke treatment variables, and detailed intraprocedural hemodynamic variables were collected. Results The entire cohort consisted of 81 (55%) females with a mean age of 66.9 ± 15.6 years and a median National Institutes of Health Stroke Scale (NIHSS) score of 16 (IQR 11-21). Thirty-six (24.5%) patients died during hospitalization, 25 (17%) achieved a 30-day modified Rankin Scale score of 0-2, and 24 (16.3%) suffered symptomatic parenchymal hematoma type 1/2 hemorrhage. Patients who achieved a good outcome had a significantly lower admission NIHSS score, a higher baseline CT ASPECTS score, and a lower rate of ICA terminus occlusions. Successful recanalization was more frequent in the good-outcome group, while symptomatic hemorrhages occurred only in poor-outcome patients. The first systolic BP (SBP; 146.5 ± 0.2 vs. 157.7 ± 25.6 mm Hg, p = 0.042), first mean arterial pressure (MAP; 98.1 ± 20.8 vs. 109.7 ± 20.3 mm Hg, p = 0.024), maximum SBP (164.6 ± 27.6 vs. 180.9 ± 18.3 mm Hg, p = 0.0003), and maximum MAP (125.5 ± 18.6 vs. 138.5 ± 24.6 mm Hg, p = 0.0309) were all significantly lower in patients who achieved good outcomes. A lower maximum intraprocedural SBP was an independent predictor of good outcome (adjusted OR 0.929, 95% CI 0.886-0.963, p = 0.0005). Initial NIHSS score was the only other independent predictor of a good outcome. Conclusion Lower intraprocedural SBP was associated with good outcome in patients undergoing IAT for AIS, and maximum SBP was an independent predictor of good outcome. SBP may be the optimal hemodynamic

  16. Abnormal systolic and diastolic myocardial function in obese asymptomatic adolescents.

    PubMed

    Batalli-Këpuska, Arbnora; Bajraktari, Gani; Zejnullahu, Murat; Azemi, Mehmedali; Shala, Mujë; Batalli, Arlind; Ibrahimi, Pranvera; Jashari, Fisnik; Henein, Michael Y

    2013-10-01

    Structural and functional cardiac changes are known in obese adults. We aimed to assess the relationship between body mass index (BMI) and cardiac function in overweight and obese asymptomatic adolescents. Ninety three healthy adolescents, aged 12.6 ± 1.2 years, received weight, height, BMI, waist, hips, waist/hips ratio assessment, hematology and biochemistry tests and an echocardiogram. Based on BMI, subjects were divided into: lean (L, n=32), overweight (Ov, n=33) and obese (Ob, n=32). Interventricular septal and LV posterior wall thickness were increased parallel to the BMI (L: 0.84 ± 0.1cm, Ov: 0.88 ± 0.1cm, Ob: 0.96 ± 0.1cm, p<0.001, and L: 0.78 ± 0.1cm, Ov: 0.8 ± 0.1cm, Ob: 0.94 ± 0.1cm, p<0.001, respectively) as were relative wall thickness (RWT) and mass index (LVMI) (L: 0.34 ± 0.05, Ov: 0.34 ± 0.05, Ob: 0.40 ± 0.04, p<0.001, and L: 47.7 ± 8.4 g/m(2), Ov: 51.9 ± 8.3g/m(2), Ob: 65.2 ± 13.3g/m(2), p=0<001, respectively). LV early diastolic (E') lateral and septal velocities (L: 15.3 ± 3.9 cm/s, Ov: 13.6 ± 4 cm/s, Ob: 10.5 ± 3.4 cm/s, p<0.001, and L: 12.2 ± 2.3 cm/s, Ov: 11.1 ± 2.4 cm/s, Ob: 9.8 ± 3.1cm/s, p=0.003, respectively), and systolic (S') velocities (L: 9.2 ± 1.4 cm/s, Ov: 9.3 ± 2.3 cm/s, Ob: 8.04 ± 1.5 cm/s, p=0.018, and L: 9.05 ± 2.3 cm/s, Ov: 9 ± 2.4 cm/s, Ob: 7.6 ± 1.1cm/s, p=0.014, respectively) were all reduced, only in obese adolescents. LV lateral E' (r=-0.44, p<0.001) and S' (r=-0.29, p=0.005) correlated with BMI. In asymptomatic adolescents, LV wall is thicker and diastolic function impaired and correlate with BMI. These findings demonstrate early cardiac functional disturbances which might explain the known obesity risk for cardiac disease. PMID:23416017

  17. Realizations and performances of least-squares estimation and Kalman filtering by systolic arrays

    SciTech Connect

    Chen, M.J.

    1987-01-01

    Fast least-squares (LS) estimation and Kalman-filtering algorithms utilizing systolic-array implementation are studied. Based on a generalized systolic QR algorithm, a modified LS method is proposed and shown to have superior computational and inter-cell connection complexities, and is more practical for systolic-array implementation. After whitening processing, the Kalman filter can be formulated as a SRIF data-processing problem followed by a simple LS operation. This approach simplifies the computational structure, and is more reliable when the system has singular or near singular coefficient matrix. To improve the throughput rate of the systolic Kalman filter, a topology for stripe QR processing is also proposed. By skewing the order of input matrices, a fully pipelined systolic Kalman-filtering operation can be achieved. With the number of processing units of the O(n/sup 2/), the system throughput rate becomes of the O(n). The numerical properties of the systolic LS estimation and the Kalman filtering algorithms under finite word-length effect are studied via analysis and computer simulations, and are compared with that of conventional approaches. Fault tolerance of the LS estimation algorithm is also discussed. It is shown that by using a simple bypass register, reasonable estimation performance is still possible for a transient defective processing unit.

  18. Techniques for design and testing of iterative and systolic arrays. [C-testability concept

    SciTech Connect

    Elhuni, H.A.

    1986-01-01

    In this thesis, the author studies the issue of testing array-type structures such as iterative arrays of combinational cells and systolic arrays with a constant number of test vectors independent of the array size (C-Testability). The main contribution of this work is the extension of the C-testability concept in different directions. It is extended to orthogonally connected iterative arrays in chapter three. This is a contribution to the C-testability theory because of the undecidability property of general two-dimensional arrays. The C-testability is extended further to hexagonal iterative arrays in chapter four. The application of the C-testability concept was limited to few arrays such as ripple-carry adders, bit-sliced microprocessors and array multipliers. In chapter five, the author extended the concept to systolic arrays and apply it to some systolic designs. The application to hexagonal systolic arrays is made in chapter six. It is shown that several systolic arrays such as those used for matrix multiplication can be tested with a small number of test vectors; twice the number required to test a single cell. The testing time of such arrays is also introduced and discussed. In chapter seven, he introduces a new concept called STV-testability for testing bilateral systolic arrays. STV-testable arrays have simple test generation and verification procedures.

  19. On the design of systolic-array architectures with applications to signal processing

    SciTech Connect

    Niamat, M.Y.

    1989-01-01

    Systolic arrays are networks of processors that rhythmically compute and paw data through systems. These arrays feature the important properties of modularity, regularity, local interconnections, and a high degree of pipelining and multiprocessing. In this dissertation, several systolic arrays are proposed with applications to real-time signal processing. Specifically, these arrays are designed for the rapid computation of position velocities, accelerations, and jerks associated with motion. Real-time computations of these parameters arise in many applications, notably in the areas of robotics, image-processing, remote signal processing, and computer-controlled machines. The systolic arrays proposed in this dissertation can be classified into the linear, the triangular, and the mesh connected types. In the linear category, six different systolic designs are presented. The relative merits of these designs are discussed in detail. It is found from the analysis of these designs that each of these arrays achieves a proportional increase in time. Also, by interleaving the input data items in some of these designs, the throughput rate is further doubled. This also increases the processor utilization rate to 100%. The triangular type systolic array is found to be useful when all three parameters are to be computed simultaneously, and the mesh type, when the number of signals to be processed are extremely large. The effect of direct broadcasting of data to the processing cells is also investigated. Finally, the utility of the proposed systolic arrays is illustrated by a practical design example.

  20. [Echocardiographic parameters and systolic times in arterial hypertension in the elderly].

    PubMed

    Pentimone, F; Santoro, G; Giusti, C; Di Bello, V; Cini, G; Del Corso, L

    1989-09-01

    In 40 subjects, 15 mean age 70.7 +/- 5.6 with systolic-diastolic hypertension, 15 mean age 75.5 +/- 6.8 years with systolic hypertension and 10 mean age 73.6 +/- 5.1 normotensive control group we have analyzed with M-mode 2D echocardiography and echophonocardiography the following parameters: diastolic--EDD--and systolic diameter--SD--of left ventricle, diastolic thickness of septum--SSD--and posterior wall--SPPD--of left ventricle, left ventricular ejection fraction--EF--(Theicholtr. formula), radius posterior wall thickness--R/SPPD--, left ventricular mass--LVM--(Devereux' formula), and systolic time intervals (Q-A2, LVET, PEP and PEP/LVET). The differences between groups are: systolic-diastolic hypertensive patients have increased EDD, SPPD and LVM, reduction of EF and increased PEP/LVET ratio in comparison with B and C groups; systolic hypertension doesn't increase EDD; SSD and PEP/LVET increase, while the EF remains within normal limits. In the healthy aged subjects SSD, SPPD and LVM are normal. PMID:2608185

  1. Randomized study of traditional versus aggressive systolic blood pressure control (Cardio-Sis): rationale, design and characteristics of the study population.

    PubMed

    2008-04-01

    The hypothesis that a therapeutic strategy aimed at lowering systolic blood pressure (SBP) below 130 mm Hg is superior to a conventional strategy targeted at below 140 mm Hg in hypertensive subjects has never been tested in randomized intervention studies. The Studio Italiano Sugli Effetti Cardiovascolari del Controllo della Pressione Arteriosa Sistolica (Cardio-Sis) is a multi-centre study in non-diabetic, treated hypertensive subjects aged >55 years with uncontrolled SBP (>or=150 mm Hg) and at least one additional cardiovascular risk factor (ClinicalTrials.gov identifier: NCT00421863). Subjects are randomized to an SBP goal <140 mm Hg (conventional) or <130 mm Hg (aggressive), independently of baseline and achieved diastolic blood pressure (BP). Anti-hypertensive drugs dispensed for the study are restricted to a list of specific drugs. The primary outcome of the study is based on regression of left ventricular hypertrophy (LVH) using electrocardiography (ECG). The hypothesis is that subjects without LVH regression or with new development of LVH 2 years after randomization are 19% with conventional strategy and 12% with aggressive strategy. Secondary outcome is a composite pool of pre-specified fatal and non-fatal events. Randomization of 1111 subjects was completed by February 2007. Mean age of subjects (41% men) at entry was 67 years. BP was 158/87 mm Hg (systolic/diastolic) and prevalence of LVH by ECG was 21.0%. Cardio-Sis is the first randomized study specifically designed to compare two different SBP goals. Results will be broadly applicable to subjects with uncontrolled SBP under anti-hypertensive treatment. PMID:18046432

  2. Cardiac MyBP-C regulates the rate and force of contraction in mammalian myocardium Cardiac Myosin Binding Protein C

    PubMed Central

    Moss, Richard L.; Fitzsimons, Daniel P.; Ralphe, J. Carter

    2014-01-01

    Cardiac myosin binding protein-C (cMyBP-C) is a thick filament-associated protein that appears to contribute to the regulation of cardiac contraction through interactions with either myosin or actin or both. Several studies over the past several years have suggested that the interactions of cMyBP-C with its binding partners vary with its phosphorylation state, binding predominantly to myosin when dephosphorylated and to actin when it is phosphorylated by PKA or other kinases. Here, we summarize evidence suggesting that phosphorylation of cMyBP-C is a key regulator of the kinetics and amplitude of cardiac contraction during β-adrenergic stimulation and increased stimulus frequency. We propose a model for these effects via a phosphorylation-dependent regulation of the kinetics and extent of cooperative recruitment of cross-bridges to the thin filament – phosphorylation of cMyBP-C accelerates cross-bridge binding to actin, thereby accelerating recruitment and increasing the amplitude of the cardiac twitch. In contrast, enhanced lusitropy as a result of phosphorylation appears to be due to a direct effect of phosphorylation to accelerate cross-bridge detachment rate. Depression or elimination of one or both of these processes in a disease such as end-stage heart failure appears to contribute to the systolic and diastolic dysfunction that characterizes the disease. PMID:25552695

  3. The design and rationale of a multi-center clinical trial comparing two strategies for control of systolic blood pressure: The Systolic Blood Pressure Intervention Trial (SPRINT)

    PubMed Central

    2014-01-01

    Background High blood pressure is an important public health concern because it is highly prevalent and a risk factor for adverse health outcomes, including coronary heart disease, stroke, decompensated heart failure, chronic kidney disease, and decline in cognitive function. Observational studies show a progressive increase in risk associated with blood pressure above 115/75 mm Hg. Prior research has shown that reducing elevated systolic blood pressure lowers the risk of subsequent clinical complications from cardiovascular disease. However, the optimal systolic blood pressure to reduce blood pressure-related adverse outcomes is unclear, and the benefit of treating to a level of systolic blood pressure well below 140 mm Hg has not been proven in a large, definitive clinical trial. Purpose To describe the design considerations of the Systolic Blood Pressure Intervention Trial (SPRINT) and the baseline characteristics of trial participants. Methods SPRINT is a multi-center, randomized, controlled trial that compares two strategies for treating systolic blood pressure: one targets the standard target of <140 mm Hg, and the other targets a more intensive target of <120 mm Hg. Enrollment focused on volunteers of age ≥50 years (no upper limit) with an average baseline systolic blood pressure ≥130 mm Hg and evidence of cardiovascular disease, chronic kidney disease, 10-year Framingham cardiovascular disease risk score ≥15%, or age ≥75 years. SPRINT recruitment also targeted three pre-specified subgroups: participants with chronic kidney disease (estimated glomerular filtration rate <60 ml/min/1.73m2), participants with a history of cardiovascular disease, and participants 75 years of age or older. The primary outcome is first occurrence of a myocardial infarction, acute coronary syndrome, stroke, heart failure, or cardiovascular disease death. Secondary outcomes include all-cause mortality, decline in kidney function or development of end-stage renal disease

  4. Subspace scheduling and parallel implementation of non-systolic regular iterative algorithms

    SciTech Connect

    Roychowdhury, V.P.; Kailath, T.

    1989-01-01

    The study of Regular Iterative Algorithms (RIAs) was introduced in a seminal paper by Karp, Miller, and Winograd in 1967. In more recent years, the study of systolic architectures has led to a renewed interest in this class of algorithms, and the class of algorithms implementable on systolic arrays (as commonly understood) has been identified as a precise subclass of RIAs include matrix pivoting algorithms and certain forms of numerically stable two-dimensional filtering algorithms. It has been shown that the so-called hyperplanar scheduling for systolic algorithms can no longer be used to schedule and implement non-systolic RIAs. Based on the analysis of a so-called computability tree we generalize the concept of hyperplanar scheduling and determine linear subspaces in the index space of a given RIA such that all variables lying on the same subspace can be scheduled at the same time. This subspace scheduling technique is shown to be asymptotically optimal, and formal procedures are developed for designing processor arrays that will be compatible with our scheduling schemes. Explicit formulas for the schedule of a given variable are determined whenever possible; subspace scheduling is also applied to obtain lower dimensional processor arrays for systolic algorithms.

  5. Impact of age on pulmonary artery systolic pressures at rest and with exercise

    PubMed Central

    Sachdev, Arun; Villarraga, Hector R; Ammash, Naser M; Oh, Jae K; McGoon, Michael D; Pellikka, Patricia A; McCully, Robert B

    2016-01-01

    Aim It is not well known if advancing age influences normal rest or exercise pulmonary artery pressures. The purpose of the study was to evaluate the association of increasing age with measurements of pulmonary artery systolic pressure at rest and with exercise. Subjects and methods A total of 467 adults without cardiopulmonary disease and normal exercise capacity (age range: 18–85 years) underwent symptom-limited treadmill exercise testing with Doppler measurement of rest and exercise pulmonary artery systolic pressure. Results There was a progressive increase in rest and exercise pulmonary artery pressures with increasing age. Pulmonary artery systolic pressures at rest and with exercise were 25±5mmHg and 33±9mmHg, respectively, in those <40 years, and 30±5mmHg and 41±12mmHg, respectively, in those ≥70 years. While elevated left-sided cardiac filling pressures were excluded by protocol design, markers of arterial stiffness associated with the age-dependent effects on pulmonary pressures. Conclusion These data demonstrate that in echocardiographically normal adults, pulmonary artery systolic pressure increases with advancing age. This increase is seen at rest and with exercise. These increases in pulmonary pressure occur in association with decreasing transpulmonary flow and increases in systemic pulse pressure, suggesting that age-associated blood vessel stiffening may contribute to these differences in pulmonary artery systolic pressure. PMID:27343212

  6. Left ventricular systolic response to exercise in patients with systemic hypertension without left ventricular hypertrophy.

    PubMed

    Christian, T F; Zinsmeister, A R; Miller, T D; Clements, I P; Gibbons, R J

    1990-05-15

    Supine exercise radionuclide angiography was performed in 367 men to assess left ventricular (LV) systolic response to exercise; 58 had systemic hypertension without LV hypertrophy on a resting electrocardiogram and 309 were normotensive. All patients met the following criteria defining a low pretest likelihood of coronary artery disease: age less than 50 years; normal electrocardiographic response to exercise; absence of typical or atypical chest pain; and exercise heart rate greater than 120 beats/min. Patients taking beta-receptor blockers were excluded. There were no significant differences between hypertensive and normotensive groups in peak exercise heart rate, workload or exercise duration. However, hypertensive patients had significantly higher peak exercise systolic blood pressures and peak exercise rate-pressure products. There were no differences between patients with and without hypertension in resting ejection fraction, peak exercise ejection fraction (hypertensive patients 0.71 +/- 0.01, normotensive patients 0.70 +/- 0.05) or change in ejection fraction at peak exercise (hypertensive patients 0.07 +/- 0.01, normotensive patients 0.07 +/- 0.04). Diastolic and systolic ventricular volumes tended to be smaller in the hypertensive patients, but the difference was not statistically significant. The change in systolic volume with exercise was similar in the 2 groups (hypertensive -10 +/- 3 ml/m2, normotensive -10 +/- 1 ml/m2). In the absence of electrocardiographic evidence of LV hypertrophy, systemic hypertension does not influence LV systolic response to exercise. PMID:2140008

  7. A systolic array for efficient execution of the radon and inverse radon transforms

    SciTech Connect

    De Groot, A.J.; Azevedo, S.G.; Schneberk, D.J.; Johansson, E.M.; Parker, S.R.

    1988-08-11

    The Systolic Processor with a Reconfigurable Interconnection Network of Transputers (SPRINT) is a sixty-four-element multiprocessor developed at Lawrence Livermore National Laboratory to evaluate systolic algorithms and architectures experimentally. The processors are interconnected in a reconfigurable network which can emulate networks such as the two-dimensional mesh, the triangular mesh, the tree, and the shuffle-exchange network. New systolic algorithms and architectures are described which perform the Radon transform and inverse Radon transform with efficiency arbitrarily close to 100%. High efficiency is possible with any connected network topology, even with low communication bandwidth. The results of the algorithms executed on the SPRINT compare closely with theory. 8 refs., 5 figs.

  8. Partitioning: An essential step in mapping algorithms into systolic array processors

    SciTech Connect

    Navarro, J.J.; Llaberia, J.M.; Valero, M.

    1987-07-01

    Many scientific and technical applications require high computing speed; those involving matrix computations are typical. For applications involving matrix computations, algorithmically specialized, high-performance, low-cost architectures have been conceived and implemented. Systolic array processors (SAPs) are a good example of these machines. An SAP is a regular array of simple processing elements (PEs) that have a nearest-neighbor interconnection pattern. The simplicity, modularity, and expandability of SAPs make them suitable for VLSI/WSI implementation. Algorithms that are efficiently executed on SAPs are called systolic algorithms (SAs). An SA uses an array of systolic cells whose parallel operations must be specified. When an SA is executed on an SAP, the specified computations of each cell are carried out by a PE of the SAP.

  9. Sudden Cardiac Arrest in Patients with Preserved Left Ventricular Systolic Function: A Clinical Dilemma

    PubMed Central

    Sawhney, Navinder; Narayan, Sanjiv M.

    2009-01-01

    Stratifying the risk for sudden cardiac arrest (SCA) in individuals with preserved systolic function remains a pressing public health problem. Current guidelines for the implantation of cardiac defibrillators largely ignore patients with preserved systolic function, even though they account for the majority of cases. However, risk stratification for such individuals is increasingly feasible. Notably, most individuals who experience SCA have structural heart disease, even if undiagnosed. Thus, clinical risk scores have been developed to identify high risk. Moreover, there are now promising data that T-Wave Alternans (TWA), alone and in combination with other indices, effectively predicts SCA in this population. This article presents our current understanding of SCA due to ventricular arrhythmias in patients with preserved LV systolic function, and attempts to build a framework to predict risk in this population. PMID:19251226

  10. Novel Strategies for the Detection of Systolic and Diastolic Heart Failure

    PubMed Central

    Bolt, Cara Lodewijks-vd; Baur, Leo; Stoffers, Jelle; Lenderink, Timo; Winkens, Ron

    2009-01-01

    The incidence and prevalence of dyspnea increases with age. Frequently, for the general practitioner with his limited diagnostic facilities, it is impossible to separate dyspnea from cardiac causes and non-cardiac causes. Without cardiac imaging it is also impossible to separate systolic dysfunction from diastolic dysfunction. After a thorough physical examination, initial screening of systolic and diastolic heart failure can be done by measurement of plasma NT-pro BNP or plasma BNP. Additionally a Chest X-Ray or ECG can be performed. To improve diagnostic performance an open access echocardiographic service can be initiated. Recent studies showed, that open access echocardiography can easily detect systolic and diastolic dysfunction in the community and can separate cardiac from non-cardiac dyspnea. PMID:20436851

  11. A Systolic Array-Based FPGA Parallel Architecture for the BLAST Algorithm

    PubMed Central

    Guo, Xinyu; Wang, Hong; Devabhaktuni, Vijay

    2012-01-01

    A design of systolic array-based Field Programmable Gate Array (FPGA) parallel architecture for Basic Local Alignment Search Tool (BLAST) Algorithm is proposed. BLAST is a heuristic biological sequence alignment algorithm which has been used by bioinformatics experts. In contrast to other designs that detect at most one hit in one-clock-cycle, our design applies a Multiple Hits Detection Module which is a pipelining systolic array to search multiple hits in a single-clock-cycle. Further, we designed a Hits Combination Block which combines overlapping hits from systolic array into one hit. These implementations completed the first and second step of BLAST architecture and achieved significant speedup comparing with previously published architectures. PMID:25969747

  12. A two-dimensional advanced systolic array and its arithmetic architecture and design

    SciTech Connect

    Jun, M.S.

    1989-01-01

    The rapid advances in the very large scale integrated (VLSI) technology has created a flurry of research in designing future computer architectures. Many methods have been developed for parallel processing of algorithms by directly mapping them onto parallel architectures. We present new methodologies for design of systolic arrays and asynchronous arrays that implement recursive algorithms efficiently. Using the new methods, we develop a systolic array with very simple local interconnection for matrix multiplication which achieves optimal performance without using any undesirable properties such as preloading input data or global broadcasting. We prove the correctness of the matrix multiplication algorithms on the systolic array with space-time parameters. The implementations of the algorithms can be easily proved and can be systolically expanded. We also develop a multi-purpose built-in logic for asynchronous self-test (BLAST) modules in processing elements. An asynchronous array for matrix multiplication which can speed up the total computation time significantly is also presented. To demonstrate the power of the proposed systolic array, the array will be applied to the shortest path problem by using the partitioned mapping approach which will be the key to extend the computational capacity of VLSI architectures with fixed size. The utilization of partitioning algorithms can overcome difficulties in the management of a large-size graph. To achieve the highest possible computation speed of the systolic array, we develop a prefix carry-lookahead adder/subtractor which achieves the maximal possible parallelism. The new carry-lookahead design leads to a high-speed adders/subtractors with regular layout. The time complexity is 2log{sub 2}n - 1 while the Brent-Kung's scheme has 4log{sub 2}n.

  13. Age-related changes to cardiac systolic and diastolic function during whole-body passive hyperthermia

    PubMed Central

    Lucas, Rebekah A. I.; Sarma, Satyam; Schlader, Zachary J.; Pearson, James; Crandall, Craig G.

    2016-01-01

    The effect of ageing on hyperthermia-induced changes in cardiac function is unknown. This study tested the hypothesis that hyperthermia-induced changes in left ventricular systolic and diastolic function are attenuated in older adults when compared with young adults. Eight older (71 ± 5 years old) and eight young adults (29 ± 5 years old), matched for sex, physical activity and body mass index, underwent whole-body passive hyperthermia. Mean arterial pressure (Finometer Pro), heart rate, forearm vascular conductance (venous occlusion plethysmography) and echocardiographic indices of diastolic and systolic function were measured during a normothermic supine period and again after an increase in internal temperature of ~1.0 °C. Hyperthermia decreased mean arterial pressure and left ventricular end-diastolic volumes and increased heart rate to a similar extent in both groups (P > 0.05). Ageing did not alter the magnitude of hyperthermia-induced changes in indices of systolic (lateral mitral annular S′ velocity) or diastolic function (lateral mitral annular E′ velocity, peak early diastolic filling and isovolumic relaxation time; P > 0.05). However, with hyperthermia the global longitudinal systolic strain increased in the older group, but was unchanged in the young group (P = 0.03). Also, older adults were unable to augment late diastolic ventricular filling [i.e. E/A ratio and A/(A + E) ratio] during hyperthermia, unlike the young (P <0.05). These findings indicate that older adults depend on a greater systolic contribution (global longitudinal systolic strain) to meet hyperthermic demand and that the atrial contribution to diastolic filling was not further augmented in older adults when compared with young adults. PMID:25641368

  14. Comparison of tree and straight-line clocking for long systolic arrays

    SciTech Connect

    Dikaiakos, M.D.; Steiglitz, K.

    1990-01-01

    This report presents the critical problem in building long systolic arrays that lies in efficient and reliable synchronization. The authors address this problem in the context of synchronous systems by introducing probabilistic models for two alternative clock distribution schemes: tree and straight-line clocking. They present analytic bounds for the probability of failure and the mean time to failure, and examine the trade-offs between reliability and throughput in both schemes. Their basic conclusion is that as the one-dimensional systolic array gets very long, tree clocking becomes more advantageous over straight-line clocking.

  15. Circuit for detecting initial systole and dicrotic notch. [for monitoring arterial pressure

    NASA Technical Reports Server (NTRS)

    Gebben, V. D.; Webb, J. A., Jr. (Inventor)

    1974-01-01

    Circuitry is disclosed for processing an arterial pressure waveform to produce during any one cycle a pulse corresponding to the initial systole and a pulse corresponding to the dicrotic notch. In a first channel, an electrical analog of the arterial pressure waveform is filtered and then compared to the original waveform to produce an initial systole signal. In a second channel, the analog is differentiated, filtered, and fed through a gate controlled by pulses from the first channel to produce an electrical pulse corresponding to the dicrotic notch.

  16. Systolic and diastolic time intervals in pulsus alternans - Significance of alternating isovolumic relaxation

    NASA Technical Reports Server (NTRS)

    Spodick, D. H.; Quarry, V. M.; Khan, A. H.

    1974-01-01

    Systolic and diastolic time intervals in 14 cardiac patients with pulsus alternans revealed significant alternation of preinjection period (PEP), isovolumic contraction time (IVCT), left ventricular ejection time (LVET), ejection time index (ETI), PEP/LVET, and carotid dD/dt with better functional values in the strong beats. Cycle length, duration of electromechanical systole (EMS) and total diastole, i.e., isovolumic relaxation period (IRP) and diastolic filling period (DFP) occurred in 7 out of 8 patients. These diastolic intervals alternated reciprocally such that the IRP of the strong beats encroached upon the DFP of the next (weak) beats.

  17. Constant-load versus heart rate-targeted exercise - Responses of systolic intervals

    NASA Technical Reports Server (NTRS)

    Lance, V. Q.; Spodick, D. H.

    1975-01-01

    Various systolic intervals were measured prior to and during heart rate-targeted bicycle ergometer exercise. There were striking similarities within each matched exercise set for Q-Im, isovolumetric contraction time, preejection period (PEP), and PEP/left ventricular ejection time (LVET). LVET was significantly shorter for rate-targeted exercise. It is concluded that either constant-load or rate-targeted bicycle ergometry may be used with the choice of method determined by the purpose of the protocol, and that systolic intervals (except LVET) should not be much altered owing to the method chosen.

  18. The 15q11.2 BP1–BP2 Microdeletion Syndrome: A Review

    PubMed Central

    Cox, Devin M.; Butler, Merlin G.

    2015-01-01

    Patients with the 15q11.2 BP1–BP2 microdeletion can present with developmental and language delay, neurobehavioral disturbances and psychiatric problems. Autism, seizures, schizophrenia and mild dysmorphic features are less commonly seen. The 15q11.2 BP1–BP2 microdeletion involving four genes (i.e., TUBGCP5, CYFIP1, NIPA1, NIPA2) is emerging as a recognized syndrome with a prevalence ranging from 0.57%–1.27% of patients presenting for microarray analysis which is a two to four fold increase compared with controls. Review of clinical features from about 200 individuals were grouped into five categories and included developmental (73%) and speech (67%) delays; dysmorphic ears (46%) and palatal anomalies (46%); writing (60%) and reading (57%) difficulties, memory problems (60%) and verbal IQ scores ≤75 (50%); general behavioral problems, unspecified (55%) and abnormal brain imaging (43%). Other clinical features noted but not considered as common were seizures/epilepsy (26%), autism spectrum disorder (27%), attention deficit disorder (ADD)/attention deficit hyperactivity disorder (ADHD) (35%), schizophrenia/paranoid psychosis (20%) and motor delay (42%). Not all individuals with the deletion are clinically affected, yet the collection of findings appear to share biological pathways and presumed genetic mechanisms. Neuropsychiatric and behavior disturbances and mild dysmorphic features are associated with genomic imbalances of the 15q11.2 BP1–BP2 region, including microdeletions, but with an apparent incomplete penetrance and variable expressivity. PMID:25689425

  19. Asiago spectroscopic classification of ASASSN-16bp

    NASA Astrophysics Data System (ADS)

    Tomasella, L.; Pastorello, A.; Benetti, S.; Cappellaro, E.; Elias-Rosa, N.; Ochner, P.; Tartaglia, L.; Terreran, G.; Turatto, M.

    2016-02-01

    The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic classification of ASASSN-16bp ( = AT 2016adq), discovered by All Sky Automated Survey for SuperNovae ASAS-SN (see Shappee et al. 2014, ApJ, 788, 48 and http://www.astronomy.ohio-state.edu/~assassin/index.shtml ), in CGCG 336-041 (Atel #8666) The observation was performed with the Asiago 1.82 m Copernico Telescope (+AFOSC; range 340-820 nm; resolution 1.4 nm). Name | Discovery UT | Obs. Date UT |z | Type | Phase |Notes ASASSN-16bp | 20160209.61 | 20160211.11 |0.034194 | Ia | ~10d | (1) (1) Also known as SN2016adq in CGCG 336-041 (z=0.034194, d=145 Mpc, via NED).

  20. Average Daily Blood Pressure, not Office Blood Pressure, is Associated with Progression of Cerebrovascular Disease and Cognitive Decline in Older People

    PubMed Central

    White, William B.; Wolfson, Leslie; Wakefield, Dorothy B.; Hall, Charles B.; Campbell, Patrick; Moscufo, Nicola; Schmidt, Julia; Kaplan, Richard F.; Pearlson, Godfrey; Guttmann, Charles R.

    2011-01-01

    Background High blood pressure (BP) is a risk factor for cerebrovascular disease, including stroke. Little is known about the importance of BP on the progression of microvascular disease of the brain that has been associated with functional decline in mobility and cognition in older people. Methods and Results This was a prospective cohort of subjects 75-89 years to determine relations among vascular risk factors, white matter hyperintensity volume (WMHs), and functional status. 99 subjects were enrolled using a balanced 3×3 matrix stratified by age and mobility performance and 72 subjects completed all sets of baseline and follow-up studies at 2 years. Subjects were excluded if there were medications, systemic or neurologic diseases that could compromise mobility. Ambulatory and clinic BP monitoring, magnetic resonance imaging (MRI), gait studies and neuropsychological testing were performed at baseline and after 24 months. Brain classification into normal white matter and T2-hyperintense WMH was performed using semi-automated segmentation. Quantitative measures of mobility and cognitive function were obtained longitudinally. Increased ambulatory systolic BP, but not clinic systolic BP, from baseline to 24 month follow-up was associated with increased WMH over that same period, as as well as measures of executive function/processing speed. Similar associations were observed for 24 hour BP, awake BP, and sleep BP, but not the surge between the sleep and awake time at the 24 month time point. Conclusions These data demonstrate for the first time the importance of 24-hour systolic BP in the progression of brain WMH burden associated with impairment of cognitive function in older people. The 24-hour systolic BP may be a potential target for intervention in the elderly to reduce vascular disease of the brain and impairment of function. PMID:22105196

  1. Systolic architectures based on barrel shifters for real-time digital signal processing

    SciTech Connect

    Chen, T.

    1985-01-01

    The throughput in real-time digital signal processing applications is limited by both the capability of the processors employed for number-crunching operations and the capacity of a supporting communications link. The systolic architectures eliminate the memory bandwidth problems by allowing multiple computations for each memory access and result in a speed-up in the execution time of compute-bound computations. However, the throughput rate in a systolic array is still limited by the computational time needed for one basic cell, which is composed of a multiplier and an accumulator. The multiplier in the basic cell requires either a large chip area if high speed is desired, or a large amount of time if serial architecture is used. The use of barrel shifters as computational elements in systolic arrays was proposed and studied in detail in this thesis. In the new systolic arrays there are two different structures, parallel and cascaded, that can be used to implement FIR filters. A unique cascaded structure was developed in this study that is shown to have better performance and requires significantly less basic cells.

  2. Systolic blood pressure reactivity during submaximal exercise and acute psychological stress in youth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Studies in youth show an association between systolic blood-pressure (SBP) reactivity to acute psychological stress and carotid artery intima-media thickness (CIMT). However, it has not yet been determined whether SBP reactivity during submaximal exercise is also associated with CIMT i...

  3. Assessment of right ventricular systolic function by echocardiography after surgical repair of congenital heart defects.

    PubMed

    Khraiche, Diala; Ben Moussa, Nidhal

    2016-02-01

    Postoperative impairment of right ventricular (RV) systolic function can appear after surgical repair of complex congenital heart defects, such as tetralogy of Fallot; it is caused by chronic volume and/or pressure overload due to pulmonary regurgitation and/or stenosis. RV dysfunction is strongly associated with prognosis in these patients. Cardiac magnetic resonance imaging is the gold standard for quantification of RV volumes and ejection fraction in patients with congenital heart diseases; however, it is costly and is not widely available. Echocardiography is the imaging modality that is most available and most frequently used to assess RV systolic function. However, RV ejection fraction cannot be measured accurately by standard two-dimensional echocardiography because of its pyramidal shape. Surrogate parameters of RV systolic function are mostly used in routine practice. New techniques of two-dimensional strain and three-dimensional quantification of RV volumes and ejection fraction have been developed in recent years. The aim of this article is to show the pertinence of each variable of RV systolic function measured by echocardiography in patients with repaired congenital heart disease and residual chronic RV overload. PMID:26774976

  4. Systolically gated 3D phase contrast MRA of mesenteric arteries in suspected mesenteric ischemia

    SciTech Connect

    Wasser, M.N.; Schultze Kool, L.J.; Roos, A. de

    1996-03-01

    Our goal was to assess the value of MRA for detecting stenoses in the celiac (CA) and superior mesenteric (SMA) arteries in patients suspected of having chronic mesenteric ischemia, using an optimized systolically gated 3D phase contrast technique. In an initial study in 24 patients who underwent conventional angiography of the abdominal vessels for different clinical indications, a 3D phase contrast MRA technique (3D-PCA) was evaluated and optimized to image the CAs and SMAs. Subsequently, a prospective study was performed to assess the value of systolically gated 3D-PCA in evaluation of the mesenteric arteries in 10 patients with signs and symptoms of chronic mesenteric ischemia. Intraarterial digital subtraction angiography and surgical findings were used as the reference standard. In the initial study, systolic gating appeared to be essential in imaging the SMA on 3D-PCA. In 10 patients suspected of mesenteric ischemia, systolically gated 3D-PCA identified significant proximal disease in the two mesenteric vessels in 4 patients. These patients underwent successful reconstruction of their stenotic vessels. Cardiac-gated MRA may become a useful tool in selection of patients suspected of having mesenteric ischemia who may benefit from surgery. 16 refs., 6 figs., 4 tabs.

  5. Exercise reveals impairments in left ventricular systolic function in patients with metabolic syndrome

    PubMed Central

    Fournier, Sara B.; Reger, Brian L.; Donley, David A.; Bonner, Daniel E.; Warden, Bradford E.; Gharib, Wissam; Failinger, Conard F.; Olfert, Melissa D.; Frisbee, Jefferson C.; Olfert, I. Mark; Chantler, Paul D.

    2013-01-01

    MetS is the manifestation of a cluster of cardiovascular (CV) risk factors and is associated with a three-fold increase risk of CV morbidity and mortality, which is suggested to be mediated, in part, by resting left ventricular (LV) systolic dysfunction. However, to what extent resting LV systolic function is impaired in MetS is controversial, and there are no data indicating whether LV systolic function is impaired during exercise. Accordingly, the objective of this study was to comprehensively examine LV and arterial responses to exercise in MetS individuals without diabetes and/or overt CVD compared to a healthy control population. CV function was characterized using Doppler echocardiography and gas exchange in MetS (n=27) vs. healthy controls (n=20) at rest and during peak exercise. At rest, MetS individuals displayed normal LV systolic function but reduced LV diastolic function vs. healthy controls. During peak exercise, individuals with MetS had impaired contractility; pump performance, and vasodilator reserve capacity vs. controls. A blunted contractile reserve response resulted in diminished arterial-ventricular coupling reserve and limited aerobic capacity in MetS vs. controls. These findings possess clinical importance as they provide insight to the pathophysiological changes in MetS that may predispose this population of individuals to an increased risk of CV morbidity and mortality. PMID:24036595

  6. Assessment of left ventricle systolic and diastolic functions in schizophrenia patients.

    PubMed

    Korkmaz, Sevda; Korkmaz, Hasan; Özer, Ömer; Atmaca, Murad

    2016-06-30

    The objective of the study was to scrutinize in detail the changes that occur in left ventricle (LV) systolic and diastolic functions using echocardiography in patients with at least 5 years of history and 40 healthy volunteers matching the patients in age and gender, who were enrolled in a cross-sectional study. All cases were examined with Tei Index, an index that could assess LV systolic and diastolic functions in conjuction, and with LV ejection fraction (LVEF) that assesses systolic function. In addition, Mitral E and A wave velocities, Isovolemic relaxation time (IVRT), Tissue Doppler Em (peak early motion) and Am (peak after motion) waves, which evaluate diastolic functions were measured. Tei Index was calculated as 0.61±0.19 in the patient group, and as 0.39±0.10 in the control group and the difference was statistically significant (p<0.001). LVEF was measured as 58%±5 in the patient group, and as 62%±3 in the control group and the difference was statistically significant (p<0.001). Also the IVRT values were significantly different between the tissue Doppler Em and Em/Am ratio among the groups (p<0.001). Echocardiographic myocardial performance, LV systolic and diastolic functions in schizophrenia patients was found to be worse than those of the control group. PMID:27138830

  7. Systolic arrays for binary image processing by using Boolean differential operators

    NASA Astrophysics Data System (ADS)

    Shmerko, V. P.; Yanushkevich, S. N.; Kochergov, E. G.

    1993-11-01

    A matrix form of the Boolean differential temporal (parametric) operators is proposed. The procedures of preliminary binary image processing (logic filtering, finding of contours) are constructed on this base. This presentation of the operators allows to synthesize the algorithms having a mapping into an architecture of systolic arrays.

  8. Nephrotoxicity of selectively deuterated and methylated analogues of Tris-BP and Bis-BP in the rat.

    PubMed

    Søderlund, E J; Omichinski, J G; Dahl, J E; Nelson, S D; Dybing, E

    1988-03-01

    Selectively deuterated and methylated analogues of the flame retardant tris(2,3-dibromopropyl)phosphate (Tris-BP) and its nephrotoxic metabolite bis(2,3-dibromopropyl)phosphate (Bis-BP) were compared to Tris-BP and Bis-BP in inducing acute renal damage in rats. None of the deuterated Tris-BP or Bis-BP analogues significantly altered morphological evidence of nephrotoxicity compared to the protio compounds. On the other hand, some of the selectively methylated analogues were much less nephrotoxic. Although the C1-methyl analogues of both Tris-BP and Bis-BP were as potent nephrotoxicants as Tris-BP and Bis-BP, respectively, neither the C2-methyl nor the C3-methyl analogues were significantly nephrotoxic. Interestingly, whereas the 3,4-dibromobutyl homologue of Tris-BP was not nephrotoxic, the corresponding 3,4-dibromobutyl-Bis homologue was as nephrotoxic as Bis-BP. Additional investigations with treatments that are known to decrease nephrotoxicity caused by several halogenated alkenes, showed that L-(alpha S,5S)-alpha-amino-3-chloro-4,5-dihydro-5-isoxazoleacetic acid (AT-125) and aminooxyacetic acid were without effects on Tris-BP induced renal damage. Probenecid pretreatment led to a reduction in Tris-BP and Bis-BP tubular necrosis, these effects may be related to inhibition of Bis-BP uptake in the kidney. It appears that the cysteine conjugate beta-lyase pathway is not involved in the generation of nephrotoxic metabolites of Tris-BP. PMID:3375186

  9. [Atrial filling fraction predicts left ventricular systolic function after myocardial infarction: pre-discharge echocardiographic evaluation].

    PubMed

    Galderisi, M; Fakher, A; Petrocelli, A; Alfieri, A; Garofalo, M; de Divitiis, O

    1995-10-01

    Aim of the study was to examine the relation between Doppler-derived indices of left ventricular diastolic and systolic function early after myocardial infarction. Fifty-three patients (31 males, 22 females) recovering from acute myocardial infarction underwent predischarge Doppler echocardiographic examination. Patients with age > 70 years, previous myocardial infarction, more than mild mitral and aortic regurgitation, mitral and aortic stenosis were excluded. Twenty-two healthy subjects (13 males; 9 females) free of coronary risk factors were selected as the control group. Both end-diastolic and end-systolic volumes and ejection fraction were measured by two-dimensional echocardiography. Pulsed Doppler was used to evaluate mitral inflow and left ventricular outflow velocity patterns. The following indices were measured: peak velocity of early (E) and late (A) flows, ratio of E/A peak velocities, ratio of early to late time velocity integrals, atrial filling fraction (time velocity integral A / time velocity integral of flow during total diastole) and deceleration time of E wave for mitral inflow; peak and time-velocity integral for left ventricular outflow. Stroke volume and cardiac output were obtained by pulsed Doppler using the left ventricular outflow method. The two groups were comparable for age, with blood pressure (p < 0.05) and heart rate (p < 0.01) reduced in myocardial infarction patients. Both end-diastolic and end-systolic volumes were significantly higher (both p < 0.0001) and ejection fraction (p < 0.0001) lower after myocardial infarction. Also stroke volume and cardiac output (both p < 0.0001) were reduced in myocardial infarction patients. No significant difference in Doppler indices of diastolic function was observed between the two groups, except for shortened deceleration time (p < 0.0001) in myocardial infarction patients. Multilinear regression analyses were performed separately into the two groups to identify determinants of left

  10. Day/Night Variability in Blood Pressure: Influence of Posture and Physical Activity

    PubMed Central

    2013-01-01

    BACKGROUND Blood pressure (BP) is highest during the day and lowest at night. Absence of this rhythm is a predictor of cardiovascular morbidity and mortality. Contributions of changes in posture and physical activity to the 24-hour day/night rhythm in BP are not well understood. We hypothesized that postural changes and physical activity contribute substantially to the day/night rhythm in BP. METHODS Fourteen healthy, sedentary, nonobese, normotensive men (aged 19–50 years) each completed an ambulatory and a bed rest condition during which BP was measured every 30–60 minutes for 24 hours. When ambulatory, subjects followed their usual routines without restrictions to capture the “normal” condition. During bed rest, subjects were constantly confined to bed in a 6-degree head-down position; therefore posture was constant, and physical activity was minimized. Two subjects were excluded from analysis because of irregular sleep timing. RESULTS The systolic and diastolic BP reduction during the sleep period was similar in ambulatory (−11±2mmHg/−8±1mmHg) and bed rest conditions (−8±3mmHg/−4±2mmHg; P = 0.38/P = 0.12). The morning surge in diastolic BP was attenuated during bed rest (P = 0.001), and there was a statistical trend for the same effect in systolic BP (P = 0.06). CONCLUSIONS A substantial proportion of the 24-hour BP rhythm remained during bed rest, indicating that typical daily changes in posture and/or physical activity do not entirely explain 24-hour BP variation under normal ambulatory conditions. However, the morning BP increase was attenuated during bed rest, suggesting that the adoption of an upright posture and/or physical activity in the morning contributes to the morning BP surge. PMID:23535155

  11. Role of echocardiography in diagnosis and risk stratification in heart failure with left ventricular systolic dysfunction

    PubMed Central

    Ciampi, Quirino; Villari, Bruno

    2007-01-01

    Heart failure (HF) is a complex clinical syndrome that can result from any structural or functional cardiac disorder that impairs the ability of the ventricle to fill with or eject blood. Echocardiography represents the "gold standard" in the assessment of LV systolic dysfunction and in the recognition of systolic heart failure, since dilatation of the LV results in alteration of intracardiac geometry and hemodynamics leading to increased morbidity and mortality. The functional mitral regurgitation is a consequence of adverse LV remodelling that occurs with a structurally normal valve and it is a marker of adverse prognosis. Diastolic dysfunction plays a major role in signs and symptoms of HF and in the risk stratification, and provides prognostic information independently in HF patients and impaired systolic function. Ultrasound lung comets are a simple echographic sign of extravascular lung water, more frequently associated with left ventricular diastolic and/or systolic dysfunction, which can integrate the clinical and pathophysiological information provided by conventional echocardiography and provide a useful information for prognostic stratification of HF patients. Contractile reserve is defined as the difference between values of an index of left ventricular contractility during peak stress and its baseline values and the presence of myocardial viability predicts a favorable outcome. A non-invasive echocardiographic method for the evaluation of force-frequency relationship has been proposed to assess the changes in contractility during stress echo. In conclusion, in HF patients, the evaluation of systolic, diastolic function and myocardial contractile reserve plays a fundamental role in the risk stratification. The highest risk is present in HF patients with a heart that is weak, big, noisy, stiff and wet. PMID:17910744

  12. The effects of the spleen tyrosine kinase inhibitor fostamatinib on ambulatory blood pressure in patients with active rheumatoid arthritis: results of the OSKIRA-ABPM (ambulatory blood pressure monitoring) randomized trial.

    PubMed

    Kitas, George D; Abreu, Gabriel; Jedrychowicz-Rosiak, Krystyna; Miller, Jeffrey L; Nakov, Roumen; Panfilov, Seva; Vencovsky, Jiri; Wang, Millie; Weinblatt, Michael E; White, William B

    2014-11-01

    Clinical trials of fostamatinib in patients with rheumatoid arthritis showed blood pressure (BP) elevation using clinic measurements. The OSKIRA-ambulatory BP monitoring trial assessed the effect of fostamatinib on 24-hour ambulatory systolic BP (SBP) in patients with active rheumatoid arthritis. One hundred thirty-five patients were randomized to fostamatinib 100 mg twice daily (bid; n = 68) or placebo bid (n = 67) for 28 days. Ambulatory, clinic, and home BPs were measured at baseline and after 28 days of therapy. Primary end point was change from baseline in 24-hour mean SBP. Fostamatinib increased 24-hour mean SBP by 2.9 mm Hg (P = .023) and diastolic BP (DBP) by 3.5 mm Hg (P < .001) versus placebo. Clinic/home-measured BPs were similar to those observed with ambulatory BP monitoring. After treatment discontinuation (1 week), clinic BP values returned to baseline levels. Fostamatinib induced elevations in 24-hour mean ambulatory SBP and DBP. BP elevations resolved with fostamatinib discontinuation. PMID:25455003

  13. How Many Measurements Are Needed to Estimate Blood Pressure Variability Without Loss of Prognostic Information?

    PubMed Central

    2014-01-01

    BACKGROUND Average real variability (ARV) is a recently proposed index for short-term blood pressure (BP) variability. We aimed to determine the minimum number of BP readings required to compute ARV without loss of prognostic information. METHODS ARV was calculated from a discovery dataset that included 24-hour ambulatory BP measurements for 1,254 residents (mean age = 56.6 years; 43.5% women) of Copenhagen, Denmark. Concordance between ARV from full (≥80 BP readings) and randomly reduced 24-hour BP recordings was examined, as was prognostic accuracy. A test dataset that included 5,353 subjects (mean age = 54.0 years; 45.6% women) with at least 48 BP measurements from 11 randomly recruited population cohorts was used to validate the results. RESULTS In the discovery dataset, a minimum of 48 BP readings allowed an accurate assessment of the association between cardiovascular risk and ARV. In the test dataset, over 10.2 years (median), 806 participants died (335 cardiovascular deaths, 206 cardiac deaths) and 696 experienced a major fatal or nonfatal cardiovascular event. Standardized multivariable-adjusted hazard ratios (HRs) were computed for associations between outcome and BP variability. Higher diastolic ARV in 24-hour ambulatory BP recordings predicted (P < 0.01) total (HR = 1.12), cardiovascular (HR = 1.19), and cardiac (HR = 1.19) mortality and fatal combined with nonfatal cerebrovascular events (HR = 1.16). Higher systolic ARV in 24-hour ambulatory BP recordings predicted (P < 0.01) total (HR = 1.12), cardiovascular (HR = 1.17), and cardiac (HR = 1.24) mortality. CONCLUSIONS Forty-eight BP readings over 24 hours were observed to be adequate to compute ARV without meaningful loss of prognostic information. PMID:23955605

  14. Right Ventricular Systolic Dysfunction Is Common in Hypertensive Heart Failure: A Prospective Study in Sub-Saharan Africa

    PubMed Central

    Ojji, Dike B.; Lecour, Sandrine; Atherton, John J.; Blauwet, Lori A.; Alfa, Jacob; Sliwa, Karen

    2016-01-01

    Introduction Right ventricular (RV) systolic dysfunction is now recognized widely as a strong and independent predictor of adverse outcomes in patients with heart failure (HF). Reduction of RV systolic function more closely predicts impaired exercise tolerance and poor survival than does left ventricular (LV) systolic function. In spite of this, there is a dearth of data on RV function in hypertensive HF which is the commonest form of HF in sub-Saharan Africa. We therefore conducted a prospective cohort study of hypertensive HF patients presenting to the University of Abuja Teaching Hospital, Abuja, Nigeria over an 8 year period. Methods Each subject had transthoracic echocardiography performed on them according to the guidelines of American Society of Echocardiography. RV systolic function was defined as a tricuspid annular plane systolic excursion (TAPSE) <15mm using M-mode echocardiography. Results RV systolic dysfunction was identified in 272 (44.5%) of the 611 subjects that were studied. Subjects with TAPSE less than 15mm had worse prognosis compared to those with TAPSE ≥15mm.There was a significant correlation between TAPSE and other adverse prognostic markers including left and right atrial area, LV size, LV mass, LV ejection fraction, restrictive mitral inflow and RV systolic pressure (RVSP). However, LV ejection fraction and right atrial area were the only independent determinants of RV systolic dysfunction. Conclusions Hypertensive HF is a major cause of RV systolic dysfunction even in a population with a low prevalence of coronary artery disease, and RV systolic dysfunction is associated with poor prognosis in hypertensive HF. Detailed assessment of RV function should therefore be part of the echocardiography evaluation of patients with hypertensive HF. PMID:27073856

  15. Time-updated systolic blood pressure and the progression of chronic kidney disease: Findings from the Chronic Renal Insufficiency Cohort (CRIC) Study

    PubMed Central

    Anderson, Amanda H; Yang, Wei; Townsend, Raymond R; Pan, Qiang; Chertow, Glenn M; Kusek, John W; Charleston, Jeanne; He, Jiang; Kallem, RadhaKrishna; Lash, James P; Miller, Edgar R; Rahman, Mahboob; Steigerwalt, Susan; Weir, Matthew; Wright, Jackson T; Feldman, Harold I

    2015-01-01

    Background Blood pressure (BP) is often inadequately controlled in patients with chronic kidney disease (CKD). Previous reports of the longitudinal association between achieved level of BP and end-stage renal disease (ESRD) have not incorporated time-updated BP with appropriate adjustment for known confounders. Objective To assess the association between baseline and time-updated systolic BP (SBP) with the progression of CKD. Design Observational, prospective cohort study (ClinicalTrials.gov identifier: NCT00304148) Setting Seven US clinical centers Patients Participants of the Chronic Renal Insufficiency Cohort (CRIC) Study (N=3,708) followed for a median (25th, 75th percentiles) of 5.7 (4.6, 6.7) years Measurements The mean of three seated SBP measurements were used as the visit-specific SBP. SBP was time-updated as the mean of that visit and all prior visits. Outcomes were ESRD and the composite renal endpoint of ESRD (dialysis or transplantation) or halving of the estimated glomerular filtration rate (eGFR). Analyses investigating baseline and time-updated SBP utilized traditional Cox proportional hazards models and marginal structural models, respectively. Results SBP was ≥130 mmHg at all study visits in 19.2% of participants, and ≥140 mmHg in 10.6%. The hazard ratio (95% confidence interval) for ESRD among participants with SBP 130–139 mmHg, compared to SBP <120 mmHg, was 1.46 (1.13–1.88) using only baseline data, and was 2.37 (1.48–3.80) using all available time-updated data. Among those with SBP ≥140 mmHg, corresponding hazard ratios were 1.46 (1.18–1.88) and 3.37 (2.26–5.03), respectively. Limitations SBP was measured once annually, and the CRIC Study cohort is not a random sample. Conclusions Among participants in the CRIC Study, time-updated SBP over 130 mmHg was more strongly associated with progression of CKD than analyses based on baseline SBP. Funding The CRIC Study is funded under cooperative agreements from the National Institute of

  16. Module to perform multiplication, division, and square root in systolic arrays for matrix computations

    SciTech Connect

    Ercegovac, M.D.; Lang, T. )

    1991-03-01

    This paper presents a module that performs multiplication, division, and square root. The implementation is compact because most of the components are shared by all three operations, the complexity being similar to a radix-2 divider. All three operations have the same execution time: one bit of the result is produced per cycle, beginning with the most significant bit. The cycle time is kept small by using redundant addition (carry-save or signed-digit) and a result-digit selection based on a low-precision estimate of the partial remainder. These properties make the module suitable for systolic arrays for matrix computations. Moreover, the communication between these modules in systolic arrays is bit-serial, yet the delay is the same as that for systems with bit-parallel communication.

  17. Instability of a Möbius Strip Minimal Surface and a Link with Systolic Geometry

    NASA Astrophysics Data System (ADS)

    Pesci, Adriana I.; Goldstein, Raymond E.; Alexander, Gareth P.; Moffatt, H. Keith

    2015-03-01

    We describe the first analytically tractable example of an instability of a nonorientable minimal surface under parametric variation of its boundary. A one-parameter family of incomplete Meeks Möbius surfaces is defined and shown to exhibit an instability threshold as the bounding curve is opened up from a double-covering of the circle. Numerical and analytical methods are used to determine the instability threshold by solution of the Jacobi equation on the double covering of the surface. The unstable eigenmode shows excellent qualitative agreement with that found experimentally for a closely related surface. A connection is proposed between systolic geometry and the instability by showing that the shortest noncontractable closed geodesic on the surface (the systolic curve) passes near the maximum of the unstable eigenmode.

  18. Interstitial fault tolerance-a technique for making systolic arrays fault tolerant

    SciTech Connect

    Kuhn, R.H.

    1983-01-01

    Systolic arrays are a popular model for the implementation of highly parallel VLSI systems. In this paper interstitial fault tolerance (IFT), a technique for incorporating fault tolerance into systolic arrays in a natural manner, is discussed. IFT can be used for reliable computation or for yield enhancement. Previous fault tolerance techniques for reliable computation on SIMD systems have employed redundant hardware. IFT on the other hand employs time redundancy. Previous wafer scale integration techniques for yield enhancement have been proposed only for linear processing element arrays. Ift is effective for both linear and two dimensional arrays. The time redundancy to achieve IFT is shown to be bounded by a factor of 3, allowing no processor redundancy. Results of monte carlo simulation of ift are presented. 19 references.

  19. Algorithm-Based Error Detection Of A Cholesky Factor Updating Systolic Array Using Cordic Processors

    NASA Astrophysics Data System (ADS)

    Chou, S. I.; Rader, Charles M.

    1989-12-01

    Lincoln Laboratory has developed an architecture for a folded linear systolic array using fixed-point CORDIC processors, applicable to adaptive nulling for a radar sidelobe canceler. The algorithm implemented uses triangularization by Givens rotations to solve a least-squares problem in the voltage domain. In this paper, the implementation of an inexpensive algorithm-based error-detection scheme is proposed for this systolic array. Column average checksum encoding is intended to detect most errors caused by the failure of any single arithmetic unit. It retains or almost retains the 100% processor utilization of Lincoln Laboratory's novel design. For the case of 64 degrees of freedom, the increase in time complexity is only 3%. The increase in hardware is mainly two adders and two comparators per CORDIC processor. We believe that the small increase in cost will be amply offset by the improvement in system performance brought about by this error detection.

  20. 5-Fluorouracil cardiotoxicity: reversible left ventricular systolic dysfunction with early detection.

    PubMed

    Iskandar, Muhammad Zaid; Quasem, Wahid; El-Omar, Magdi

    2015-01-01

    A 33-year-old man presented to hospital with acute shortness of breath and evolving ST segment changes on ECG 3 days following a cycle of 5-fluorouracil (5-FU) for colon cancer. Despite no cardiac history, subsequent echocardiogram showed severe left ventricular systolic dysfunction. The patient was initially treated with heart failure medications and his coronary angiogram was normal. Chemotherapy was stopped and he was started on nitrates and calcium channel blockers. A repeat echocardiogram and cardiac MRI a week later showed complete resolution of his left ventricular dysfunction and he was discharged home. This case report summarises 5-FU cardiotoxicity, and emphasises the importance of early recognition and correct treatment, as left ventricular systolic dysfunction in this context is potentially reversible. PMID:25935919

  1. Effect of hematocrit and systolic blood pressure on cerebral blood flow in newborn infants

    SciTech Connect

    Younkin, D.P.; Reivich, M.; Jaggi, J.L.; Obrist, W.D.; Delivoria-Papadopoulos, M.

    1987-06-01

    The effects of hematocrit and systolic blood pressure on cerebral blood flow were measured in 15 stable, low birth weight babies. CBF was measured with a modification of the xenon-133 (/sup 133/Xe) clearance technique, which uses an intravenous bolus of /sup 133/Xe, an external chest detector to estimate arterial /sup 133/Xe concentration, eight external cranial detectors to measure cephalic /sup 133/Xe clearance curves, and a two-compartmental analysis of the cephalic /sup 133/Xe clearance curves to estimate CBF. There was a significant inverse correlation between hematocrit and CBF, presumably due to alterations in arterial oxygen content and blood viscosity. Newborn CBF varied independently of systolic blood pressure between 60 and 84 mm Hg, suggesting an intact cerebrovascular autoregulatory mechanism. These results indicate that at least two of the factors that affect newborn animal CBF are operational in human newborns and may have important clinical implications.

  2. Vascular calcification is not associated with increased ambulatory central aortic systolic pressure in prevalent dialysis patients

    PubMed Central

    Freercks, Robert J; Swanepoel, Charles R; Turest-Swartz, Kristy L; Rayner, Brian L; Carrara, Henri RO; Moosa, Sulaiman EI; Lachman, Anthony S

    2014-01-01

    Summary Introduction Central aortic systolic pressure (CASP) strongly predicts cardiovascular outcomes. We undertook to measure ambulatory CASP in 74 prevalent dialysis patients using the BPro (HealthStats, Singapore) device. We also determined whether coronary or abdominal aortic calcification was associated with changes in CASP and whether interdialytic CASP predicted ambulatory measurement. Methods All patients underwent computed tomography for coronary calcium score, lateral abdominal radiography for aortic calcium score, echocardiography for left ventricular mass index and ambulatory blood pressure measurement using BPro calibrated to brachial blood pressure. HealthStats was able to convert standard BPro SOFT® data into ambulatory CASP. Results Ambulatory CASP was not different in those without and with coronary (137.6 vs 141.8 mmHg, respectively, p = 0.6) or aortic (136.6 vs 145.6 mmHg, respectively, p = 0.2) calcification. Furthermore, when expressed as a percentage of brachial systolic blood pressure to control for peripheral blood pressure, any difference in CASP was abolished: CASP: brachial systolic blood pressure ratio = 0.9 across all categories regardless of the presence of coronary or aortic calcification (p = 0.2 and 0.4, respectively). Supporting this finding, left ventricular mass index was also not different in those with or without vascular calcification (p = 0.7 and 0.8 for coronary and aortic calcification). Inter-dialytic office blood pressure and CASP correlated excellently with ambulatory measurements (r = 0.9 for both). Conclusion Vascular calcification was not associated with changes in ambulatory central aortic systolic pressure in this cohort of prevalent dialysis patients. Inter-dialytic blood pressure and CASP correlated very well with ambulatory measurement. PMID:24626513

  3. Doppler-derived myocardial systolic strain rate is a strong index of left ventricular contractility

    NASA Technical Reports Server (NTRS)

    Greenberg, Neil L.; Firstenberg, Michael S.; Castro, Peter L.; Main, Michael; Travaglini, Agnese; Odabashian, Jill A.; Drinko, Jeanne K.; Rodriguez, L. Leonardo; Thomas, James D.; Garcia, Mario J.

    2002-01-01

    BACKGROUND: Myocardial fiber strain is directly related to left ventricular (LV) contractility. Strain rate can be estimated as the spatial derivative of velocities (dV/ds) obtained by tissue Doppler echocardiography (TDE). The purposes of the study were (1) to determine whether TDE-derived strain rate may be used as a noninvasive, quantitative index of contractility and (2) to compare the relative accuracy of systolic strain rate against TDE velocities alone. METHODS AND RESULTS: TDE color M-mode images of the interventricular septum were recorded from the apical 4-chamber view in 7 closed-chest anesthetized mongrel dogs during 5 different inotropic stages. Simultaneous LV volume and pressure were obtained with a combined conductance-high-fidelity pressure catheter. Peak elastance (Emax) was determined as the slope of end-systolic pressure-volume relationships during caval occlusion and was used as the gold standard of LV contractility. Peak systolic TDE myocardial velocities (Sm) and peak (epsilon'(p)) and mean (epsilon'(m)) strain rates obtained at the basal septum were compared against Emax by linear regression. Emax as well as TDE systolic indices increased during inotropic stimulation with dobutamine and decreased with the infusion of esmolol. A stronger association was found between Emax and epsilon'(p) (r=0.94, P<0.01, y=0.29x+0.46) and epsilon'(m) (r=0.88, P<0.01) than for Sm (r=0.75, P<0.01). CONCLUSIONS: TDE-derived epsilon'(p) and epsilon'(m) are strong noninvasive indices of LV contractility. These indices appear to be more reliable than S(m), perhaps by eliminating translational artifact.

  4. On realizations of least-squares estimation and Kalman filtering by systolic arrays

    NASA Technical Reports Server (NTRS)

    Chen, M. J.; Yao, K.

    1986-01-01

    Least-squares (LS) estimation is a basic operation in many signal processing problems. Given y = Ax + v, where A is a m x n coefficient matrix, y is a m x 1 observation vector, and v is a m x 1 zero mean white noise vector, a simple least-squares solution is finding the estimated vector x which minimizes the norm of /Ax-y/. It is well known that for an ill-conditioned matrix A, solving least-squares problems by orthogonal triangular (QR) decomposition and back substitution has robust numerical properties under finite word length effect since 2-norm is preserved. Many fast algorithms have been proposed and applied to systolic arrays. Gentleman-Kung (1981) first presented the trianglular systolic array for a basic Givens reduction. McWhirter (1983) used this array structure to find the least-squares estimation errors. Then by geometric approach, several different systolic array realizations of the recursive least-squares estimation algorithms of Lee et al (1981) were derived by Kalson-Yao (1985). Basic QR decomposition algorithms are considered in this paper and it is found that under a one-row time updating situation, the Householder transformation degenerates to a simple Givens reduction. Next, an improved least-squares estimation algorithm is derived by considering a modified version of fast Givens reduction. From this approach, the basic relationship between Givens reduction and Modified-Gram-Schmidt transformation can easily be understood. This improved algorithm also has simpler computational and inter-cell connection complexities while compared with other known least-squares algorithms and is more realistic for systolic array implementation.

  5. Effects of Parental Smoking on Exercise Systolic Blood Pressure in Adolescents

    PubMed Central

    Hacke, Claudia; Weisser, Burkhard

    2015-01-01

    Background In adults, exercise blood pressure seems to be more closely related to cardiovascular risk than resting blood pressure; however, few data are available on the effects of familial risk factors, including smoking habits, on exercise blood pressure in adolescents. Methods and Results Blood pressure at rest and during exercise, parental smoking, and other familial risk factors were investigated in 532 adolescents aged 12 to 17 years (14.6±1.5 years) in the Kiel EX.PRESS. (EXercise PRESSure) Study. Exercise blood pressure was determined at 1.5 W/kg body weight using a standardized submaximal cycle ergometer test. Mean resting blood pressure was 113.1±12.8/57.2±7.1 mm Hg, and exercise blood pressure was 149.9±19.8/54.2±8.6 mm Hg. Parental smoking increased exercise systolic blood pressure (+4.0 mm Hg, 3.1 to 4.9; P=0.03) but not resting blood pressure of the subjects (adjusted for age, sex, height, body mass index percentile, fitness). Parental overweight and familial hypertension were related to both higher resting and exercise systolic blood pressure values, whereas associations with an inactive lifestyle and a low educational level of the parents were found only with adolescents’ blood pressure during exercise. The cumulative effect of familial risk factors on exercise systolic blood pressure was more pronounced than on blood pressure at rest. Conclusions Parental smoking might be a novel risk factor for higher blood pressure, especially during exercise. In addition, systolic blood pressure during a submaximal exercise test was more closely associated with familial risk factors than was resting blood pressure, even in adolescents. PMID:25964207

  6. Bit-systolic arithmetic arrays using dynamic differential gallium arsenide circuits

    NASA Technical Reports Server (NTRS)

    Beagles, Grant; Winters, Kel; Eldin, A. G.

    1992-01-01

    A new family of gallium arsenide circuits for fine grained bit-systolic arithmetic arrays is introduced. This scheme combines features of two recent techniques of dynamic gallium arsenide FET logic and differential dynamic single-clock CMOS logic. The resulting circuits are fast and compact, with tightly constrained series FET propagation paths, low fanout, no dc power dissipation, and depletion FET implementation without level shifting diodes.

  7. Assessment of LV systolic function in atrial fibrillation using an index of preceding cardiac cycles.

    PubMed

    Tabata, T; Grimm, R A; Greenberg, N L; Agler, D A; Mowrey, K A; Wallick, D W; Zhang, Y; Zhuang, S; Mazgalev, T N; Thomas, J D

    2001-08-01

    The clinical assessment of left ventricular (LV) systolic function during atrial fibrillation (AF) is unreliable and difficult because of beat-to-beat variability. We evaluated an index for the estimation of LV systolic function in AF that is based on the relationship between the preceding (R-R1) and prepreceding (R-R2) R-R intervals. LV Doppler stroke volume (SV), ejection fraction (EF), peak aortic flow rate (AoF) and the maximum value of the first derivative of the LV pressure curve (dP/dt(max)) were evaluated in 13 healthy open-chest dogs during triggered AF. All parameters showed a significantly strong positive linear relationship with the ratio of R-R1/R-R2 (r = 0.65, 0.74, 0.75, and 0.70 for SV, EF, AoF, and dP/dt(max), respectively). The calculated value of LV systolic parameters at R-R1/R-R2 = 1 in the linear regression line showed a good relationship and an agreement with the measured average value of the parameter over all cardiac cycles (SV, 12.1 vs. 12.8 ml; EF, 49.6 vs. 51.2%; AoF, 1.37 vs. 1.48 l/min; and dP/dt(max), 2,323 vs. 2,454 mmHg/s). Using the LV systolic parameters estimated at R-R1/R-R2 = 1 in the linear regression line allows the LV contractile function to be accurately and reproducibly evaluated during AF and obviates the less-reliable process of averaging multiple cardiac cycles. PMID:11454559

  8. A Systolic VLSI Design of a Pipeline Reed-solomon Decoder

    NASA Technical Reports Server (NTRS)

    Shao, H. M.; Truong, T. K.; Deutsch, L. J.; Yuen, J. H.; Reed, I. S.

    1984-01-01

    A pipeline structure of a transform decoder similar to a systolic array was developed to decode Reed-Solomon (RS) codes. An important ingredient of this design is a modified Euclidean algorithm for computing the error locator polynomial. The computation of inverse field elements is completely avoided in this modification of Euclid's algorithm. The new decoder is regular and simple, and naturally suitable for VLSI implementation.

  9. Tricuspid annular plane systolic excursion and pulmonary arterial systolic pressure relationship in heart failure: an index of right ventricular contractile function and prognosis.

    PubMed

    Guazzi, M; Bandera, F; Pelissero, G; Castelvecchio, S; Menicanti, L; Ghio, S; Temporelli, P L; Arena, R

    2013-11-01

    Echo-derived pulmonary arterial systolic pressure (PASP) and right ventricular (RV) tricuspid annular plane systolic excursion (TAPSE; from the end of diastole to end-systole) are of basic relevance in the clinical follow-up of heart failure (HF) patients, carrying two- to threefold increase in cardiac risk when increased and reduced, respectively. We hypothesized that the relationship between TAPSE (longitudinal RV fiber shortening) and PASP (force generated by the RV) provides an index of in vivo RV length-force relationship, with their ratio better disclosing prognosis. Two hundred ninety-three HF patients with reduced (HFrEF, n = 247) or with preserved left ventricular (LV) ejection fraction (HFpEF, n = 46) underwent echo-Doppler studies and N-terminal pro-brain-type natriuretic peptide assessment and were tracked for adverse events. The median follow-up duration was 20.8 mo. TAPSE vs. PASP relationship showed a downward regression line shift in nonsurvivors who were more frequently presenting with higher PASP and lower TAPSE. HFrEF and HFpEF patients exhibited a similar distribution along the regression line. Given the TAPSE, PASP, and TAPSE-to-PASP ratio (TAPSE/PASP) collinearity, separate Cox regression and Kaplan-Meier analyses were performed: one with TAPSE and PASP as individual measures, and the other combining them in ratio form. Hazard ratios for variables retained in the multivariate regression were as follows: TAPSE/PASP

  10. Left ventricular outflow tract mean systolic acceleration as a surrogate for the slope of the left ventricular end-systolic pressure-volume relationship

    NASA Technical Reports Server (NTRS)

    Bauer, Fabrice; Jones, Michael; Shiota, Takahiro; Firstenberg, Michael S.; Qin, Jian Xin; Tsujino, Hiroyuki; Kim, Yong Jin; Sitges, Marta; Cardon, Lisa A.; Zetts, Arthur D.; Thomas, James D.

    2002-01-01

    OBJECTIVE: The goal of this study was to analyze left ventricular outflow tract systolic acceleration (LVOT(Acc)) during alterations in left ventricular (LV) contractility and LV filling. BACKGROUND: Most indexes described to quantify LV systolic function, such as LV ejection fraction and cardiac output, are dependent on loading conditions. METHODS: In 18 sheep (4 normal, 6 with aortic regurgitation, and 8 with old myocardial infarction), blood flow velocities through the LVOT were recorded using conventional pulsed Doppler. The LVOT(Acc) was calculated as the aortic peak velocity divided by the time to peak flow; LVOT(Acc) was compared with LV maximal elastance (E(m)) acquired by conductance catheter under different loading conditions, including volume and pressure overload during an acute coronary occlusion (n = 10). In addition, a clinically validated lumped-parameter numerical model of the cardiovascular system was used to support our findings. RESULTS: Left ventricular E(m) and LVOT(Acc) decreased during ischemia (1.67 +/- 0.67 mm Hg.ml(-1) before vs. 0.93 +/- 0.41 mm Hg.ml(-1) during acute coronary occlusion [p < 0.05] and 7.9 +/- 3.1 m.s(-2) before vs. 4.4 +/- 1.0 m.s(-2) during coronary occlusion [p < 0.05], respectively). Left ventricular outflow tract systolic acceleration showed a strong linear correlation with LV E(m) (y = 3.84x + 1.87, r = 0.85, p < 0.001). Similar findings were obtained with the numerical modeling, which demonstrated a strong correlation between predicted and actual LV E(m) (predicted = 0.98 [actual] -0.01, r = 0.86). By analysis of variance, there was no statistically significant difference in LVOT(Acc) under different loading conditions. CONCLUSIONS: For a variety of hemodynamic conditions, LVOT(Acc) was linearly related to the LV contractility index LV E(m) and was independent of loading conditions. These findings were consistent with numerical modeling. Thus, this Doppler index may serve as a good noninvasive index of LV

  11. Assessment of longitudinal systolic ventricular dysfunction and asynchrony using velocity vector imaging in children with a single right ventricle.

    PubMed

    Wu, Yu-Rong; Zhang, Yu-Qi; Chen, Li-Jun; Wang, Shan-Shan; Zhong, Shu-Wen; Zhang, Zhi-Fang

    2014-10-01

    Assessment of ventricular dysfunction and asynchrony is very important in predicting the outcome for children with a single right ventricle. However, the assessment is inaccurate and subjective because of the unusual ventricular shape. This study aimed to evaluate the feasibility and clinical value of velocity vector imaging for assessing longitudinal systolic ventricular dysfunction and intraventricular asynchrony in children with a single right ventricle. The study enrolled 36 children with a single right ventricle and 36 age-matched children with a normal heart. Peak systolic velocity, peak displacement, strain, strain rate, time to peak systolic velocity, and time to peak systolic strain were measured via velocity vector imaging using the Siemens Sequoia C512 echocardiography instrument. The maximum positive rate of ventricular pressure change (Max [dp/dt]) was obtained by cardiac catheterization for all the children with a single right ventricle. In the children with a single right ventricle, the maximal temporal differences and the standard deviations of the times to peak systolic velocity and peak systolic strain were higher (P < 0.01) than in the children with a normal heart. Moreover, the strain and strain rate values were significantly lower in all six segments (P < 0.05). The strain rate of the basal segment adjacent to the rudimentary chamber correlated best with Max (dp/dt) (r = 0.86; P < 0.01). Longitudinal systolic dysfunction and intraventricular asynchrony could be assessed accurately using velocity vector imaging in children with a single right ventricle. PMID:24771060

  12. Measurements of systolic time intervals using a transoesophageal pulsed echo-Doppler.

    PubMed

    Tournadre, J P; Muchada, R; Lansiaux, S; Chassard, D

    1999-10-01

    Measurement of systolic time intervals (STI), an index of left ventricular (LV) systolic function, is usually labour intensive and requires considerable expertise to perform accurately. We have evaluated the accuracy of an automated, continuous and non-invasive STI measurement technique using a descending aortic blood velocity Doppler signal obtained using a transoesophageal echo-Doppler system (TEDS) and an ECG signal. STI were measured in adult pigs using a transoesophageal probe (4 x 4 mm pulsed wave Doppler transducer, 5-MHz frequency and a 3 x 3 mm echo transducer, 10-MHz frequency) associated with an ECG recorder. Measurements were performed at baseline and after injection of esmolol and dobutamine. TEDS data were compared with those obtained by one-line recordings of the electrocardiogram and the central aortic arterial pressure wave. Similar mean values were observed for pre-ejection period (PEPI), LV ejection time (LVET) and PEP/LVET with the two methods. Agreement between the methods (Bland and Altman's test) was excellent with 95% confidence intervals for PEP, LVET and PEP/LVET of -7.17 to +1.37 ms, -12.64 to +0.24 ms and -0.033 to +0.028, respectively. We conclude that the combination of descending aorta blood velocity Doppler and ECG signal is an alternative technique for non-invasive and objective measurement of STI, allowing continuous monitoring of LV systolic function. PMID:10673883

  13. Mechanically certified derivation of concurrency and its application to systolic design

    SciTech Connect

    Huang, C.H.

    1987-01-01

    The authors approach in developing parallel traces is by trace transformation. A transformation takes a sequential trace and transforms it into a parallel trace. Trace transformation must preserve the semantics of executions but may alter their execution time. In order to reason about the properties of a programming language precisely, a formal semantics is needed. A semantic theory composed of trace semantics and trace transformation rules implemented in the Boyer-Moore mechanical logic. The semantic theory is studied on a particular programming language, sorting networks. Sequential and parallel traces are defined for several sorting networks, and it is proved that they are semantically equivalent. Also presented is a transformation strategy, and proving that it preserves semantics. The transformation strategy is employed in a design method of systolic architectures. A systolic architecture is a network of processors that are connected in simple patterns and perform simple operations under global synchronization. The development of a systolic architecture requires the input of a processor layout and produces processor connections and data layout. The author implemented the design method on the Symbolics 3600.

  14. Intrinsic Frequency Method for Noninvasive Diagnosis of Left Ventricular Systolic Dysfunction

    NASA Astrophysics Data System (ADS)

    Pahlevan, Niema; Rinderknecht, Derek; Tavallali, Peyman; Petrasek, Danny; Matthews, Ray; Gharib, Morteza

    2014-11-01

    We have recently developed a new mathematical method, intrinsic frequency (IF) method, that views the left ventricle-arterial system as a coupled dynamic pumping system which is decoupled upon the closure of the aortic valve. Utilizing this method, given an arterial blood pressure waveform we are able to extract two intrinsic frequencies (ω1 and ω2) correlating to systole when the left ventricle (LV) and aorta (vasculature) act as a coupled dynamic pumping system and diastole where the dynamics of the LV is removed. Each of these dynamical pumping states has an inherent frequency of operation (ω1 and ω2) which gives information about LV systolic function (ω1) as well as arterial dynamics (ω2) . IF methodology extracts ω1 and ω2 from the pressure wave. This method was applied to invasive aortic pressure waveforms and noninvasively measured carotid pressure waveforms. Our results shows that ω1 is elevated in patients with LV systolic dysfunction (LVSD). However, ω1 remains relatively constant under healthy conditions as age advances. Our results indicate that IF methodology can be used to detect LVSD from a single pressure waveform. One unique advantage of the IF method is only the shape of the waveform is required. Therefore, ω1 can be easily derived from noninvasive measurements and monitored continuously.

  15. On mapping algorithms to linear and fault-tolerant systolic arrays

    SciTech Connect

    Kumar, V.K.P.; Tsai, Y.C.

    1989-03-01

    The authors develop a simple mapping technique to design systolic arrays with limited I/O capability. Using this, improved systolic algorithms are derived for some matrix computations, on linearly connected arrays of processing elements (PEs) with constant I/O bandwidth. The important features of these designs are modularity with constant hardware in each PE, few control lines, simple data input/ouput format, and improved delay time. They extend the technique to design an optimal time systolic algorithm for n x n matrix multiplication. In this model, the propagation delay is assumed to be proportional to wire length. Fault reconfiguration is achieved by using buffers to bypass faulty PE's, which does not affect the clock rate of the system. The unidirectional flow of control and data in our design assures correctness of the algorithm in the presence of faulty PE's. This design can be implemented on reconfigurable fault-tolerant VLSI arrays using the Diogenes methodology. The authors compare their designs to those in the literature and are shown to be superior with respect to I/O format, control, and delay from input to output.

  16. Exposure to fipronil elevates systolic blood pressure and disturbs related biomarkers in plasma of rats.

    PubMed

    Chaguri, Joao Leandro; Godinho, Antonio Francisco; Horta, Daniel França; Gonçalves-Rizzi, Victor Hugo; Possomato-Vieira, Jose Sergio; Nascimento, Regina Aparecida; Dias-Junior, Carlos Alan

    2016-03-01

    Recent reports show that fipronil affects non-target organisms, including environmental species populations and potentially humans. We aimed to examine if fipronil exposure affects the systolic blood pressure and related biomarkers. Thus, fipronil was orally administered to rats (30 mg/kg/day) during 15 days (Fipronil group) or physiological solution (Control group). While fipronil increased significantly the systolic blood pressure (158±13 mmHg), no significant changes were observed in Control group (127±3 mmHg). Significantly, higher levels of fipronil in plasma were observed in Fipronil group (0.46±0.09 μg/mL versus 0.17±0.11 μg/mL in Control group). Fipronil group showed lower weight gain compared with Control group. While fipronil resulted in higher concentrations of endothelin-1, reduced antioxidant capacity and lower levels of circulating matrix metalloproteinase 2 (MMP-2) and nitric oxide (NO) metabolites compared to Control group, no alteration was observed in serum biomarkers of renal and hepatic/biliary functional abilities. Therefore, this study suggests that fipronil causes hypertension and endothelin-1 plays a key role. Also, these findings suggest that reductions of both MMP-2 and NO may contribute with the elevation of systolic blood pressure observed with fipronil. PMID:26773360

  17. Effect of food intake on left and right ventricular systolic tissue Doppler measurements.

    PubMed

    Dieden, Anna; Gårdinger, Ylva; Hlebowicz, Joanna; Björgell, Ola; Dencker, Magnus

    2016-09-01

    Systolic tissue Doppler measurements (s') have been used to measure the velocity in myocardial motion and are a valuable tool for evaluating the systolic function of the left and right ventricles. Digestion of food is known to significantly alter hemodynamics and may therefore affect s'. The effect of food intake on s' parameters has not yet been studied. We assessed whether s' is affected by food intake. Nineteen healthy subjects aged 26·2 ± 4·2 years were investigated. s' was measured with pulsed tissue Doppler imaging in the right and left ventricles before the subjects ate a standardized meal and also 30 and 110 min after the meal. Three measurements were taken in each projection, and a mean value was calculated for each. s' increased significantly (P<0·05) from fasting to 30 min after food intake in every measured site except in the left inferolateral wall (P = 0·15, NS). Several, but not all, variables returned to base value 110 min after food intake. This study shows that food intake affects the tissue Doppler variables used to evaluate systolic heart function. Further studies are needed in older healthy subjects and older subjects with various cardiovascular diseases. PMID:25976703

  18. Remote detection of photoplethysmographic systolic and diastolic peaks using a digital camera.

    PubMed

    McDuff, Daniel; Gontarek, Sarah; Picard, Rosalind W

    2014-12-01

    We present a new method for measuring photoplethysmogram signals remotely using ambient light and a digital camera that allows for accurate recovery of the waveform morphology (from a distance of 3 m). In particular, we show that the peak-to-peak time between the systolic peak and diastolic peak/inflection can be automatically recovered using the second-order derivative of the remotely measured waveform. We compare measurements from the face with those captured using a contact fingertip sensor and show high agreement in peak and interval timings. Furthermore, we show that results can be significantly improved using orange, green, and cyan color channels compared to the tradition red, green, and blue channel combination. The absolute error in interbeat intervals was 26 ms and the absolute error in mean systolic-diastolic peak-to-peak times was 12 ms. The mean systolic-diastolic peak-to-peak times measured using the contact sensor and the camera were highly correlated, ρ = 0.94 (p 0.001). The results were obtained with a camera frame-rate of only 30 Hz. This technology has significant potential for advancing healthcare. PMID:25073159

  19. Assessment of systolic and diastolic function in heart failure using ambulatory monitoring with acoustic cardiography.

    PubMed

    Dillier, Roger; Zuber, Michel; Arand, Patricia; Erne, Susanne; Erne, Paul

    2011-08-01

    INTRODUCTION. The circadian variation of heart function and heart sounds in patients with and without heart failure (HF) is poorly understood. We hypothesized HF patients would exhibit less circadian variation with worsened cardiac function and sleep apnea. METHODS. We studied 67 HF patients (age 67.4 ± 8.2 years; 42% acute HF) and 63 asymptomatic control subjects with no history of HF (age 61.6 ± 7.7 years). Subjects wore a heart sound/ECG/respiratory monitor. The data were analyzed for sleep apnea, diastolic heart sounds, and systolic time intervals. RESULTS. The HF group had significantly greater prevalence of the third heart sound and prolongation of electro-mechanical activation time, while the control group had an age-related increase in the prevalence of the fourth heart sound. The control group showed more circadian variation in cardiac function. The HF subjects had more sleep apnea and higher occurrence of heart rate non-dipping. CONCLUSIONS. The control subjects demonstrated an increasing incidence of diastolic dysfunction with age, while systolic function was mostly unchanged with aging. Parameters related to systolic function were significantly worse in the HF group with little diurnal variation, indicating a constant stimulation of sympathetic tone in HF and reduction of diurnal regulation. PMID:21361859

  20. Comparison of systolic blood pressure values obtained by photoplethysmography and by Korotkoff sounds.

    PubMed

    Nitzan, Meir; Adar, Yair; Hoffman, Ellie; Shalom, Eran; Engelberg, Shlomo; Ben-Dov, Iddo Z; Bursztyn, Michael

    2013-01-01

    In the current study, a non-invasive technique for systolic blood pressure (SBP) measurement based on the detection of photoplethysmographic (PPG) pulses during pressure-cuff deflation was compared to sphygmomanometry-the Korotkoff sounds technique. The PPG pulses disappear for cuff-pressures above the SBP value and reappear when the cuff-pressure decreases below the SBP value. One hundred and twenty examinations were performed on forty subjects. In 97 examinations the two methods differed by less than 3 mmHg. In nine examinations the SBP value measured by PPG was higher than that measured by sphygmomanometry by 5 mmHg or more. In only one examination the former was lower by 5 mmHg or more than the latter. The appearance of either the PPG pulses or the Korotkoff sounds assures that the artery under the cuff is open during systolic peak pressure. In the nine examinations mentioned above the PPG pulses were observed while Korotkoff sounds were not detected, despite the open artery during systole. In these examinations, the PPG-based technique was more reliable than sphygmomanometry. The high signal-to-noise ratio of measured PPG pulses indicates that automatic measurement of the SBP by means of automatic detection of the PPG signals is feasible. PMID:24184918

  1. Comparison of Systolic Blood Pressure Values Obtained by Photoplethysmography and by Korotkoff Sounds

    PubMed Central

    Nitzan, Meir; Adar, Yair; Hoffman, Ellie; Shalom, Eran; Engelberg, Shlomo; Ben-Dov, Iddo Z.; Bursztyn, Michael

    2013-01-01

    In the current study, a non-invasive technique for systolic blood pressure (SBP) measurement based on the detection of photoplethysmographic (PPG) pulses during pressure-cuff deflation was compared to sphygmomanometry—the Korotkoff sounds technique. The PPG pulses disappear for cuff-pressures above the SBP value and reappear when the cuff-pressure decreases below the SBP value. One hundred and twenty examinations were performed on forty subjects. In 97 examinations the two methods differed by less than 3 mmHg. In nine examinations the SBP value measured by PPG was higher than that measured by sphygmomanometry by 5 mmHg or more. In only one examination the former was lower by 5 mmHg or more than the latter. The appearance of either the PPG pulses or the Korotkoff sounds assures that the artery under the cuff is open during systolic peak pressure. In the nine examinations mentioned above the PPG pulses were observed while Korotkoff sounds were not detected, despite the open artery during systole. In these examinations, the PPG-based technique was more reliable than sphygmomanometry. The high signal-to-noise ratio of measured PPG pulses indicates that automatic measurement of the SBP by means of automatic detection of the PPG signals is feasible. PMID:24184918

  2. Pre- and postflight systolic time intervals during LBNP: the second manned Skylab mission.

    PubMed

    Bergman, S A; Hoffler, G W; Johnson, R L; Wolthuis, R A

    1976-04-01

    After space flight of 59 d, Skylab 3 astronauts were stressed with lower body negative pressure (LBNP). During this stress procedure vectorcardiograms, pneumograms, phonocardiograms, and carotid pulse tracings were monitored and recorded onto analog tape. Accepted techniques were used to measure the intervals of systole. The postflight results were compared to multiple preflight tests and each of the three crewmen served as his own control. Immediately postflight, there were elevations in heart rate and blood pressure in response to a fixed level (-50 mm Hg) of LBNP. Total electromechanical systole, (Q-S2) I, was unchanged. Ejection time index (ETI) was depressed at rest and during stress, while pre-ejection period was elevated compared with preflight values. Systolic time intervals (STI) were within preflight limits after 1 month on earth in all crewmen. Resting STI returned sooner than did stressed STI. The magnitude and direction of STI in the postflight period were similar to those obtained from patients with moderate heart disease, although signs and symptoms were absent in the astronauts. However, the abnormality of the stressed STI persisted after both blood volume repletion and lowered afterload. These findings suggest a compromise in cardiac function, peripheral circulatory integrity, or both after exposure to long-duration space flight, and are consistent with findings reported after 3 weeks of absolute bedrest. PMID:1275822

  3. Noninvasive monitoring of systolic blood pressure on the arm utilizing photoplethysmography (PPG): clinical report

    NASA Astrophysics Data System (ADS)

    Laurent, Claes; Jonsson, Bjorn; Vegfors, Magnus; Eneling, Martin; Lindberg, Lars-Goran

    2004-07-01

    A soft (silicone) probe, containing six light emitting diodes (880 nm) and three photo detectors, utilizes photoplethysmography (PPG) to monitor pulsations from the brachialis artery under an occluding cuff during deflation. When the arterial pulse returns, measured by PPG, the corresponding pressure in the cuff is determined. This pressure is assumed to equal the systolic pressure. An assessment trial was performed on 21 patients (9 women and 12 men, aged 27-69) at the Neuro-Intensive care unit. Since the patients were already provided with arterial needles, invasive blood pressure could be used as the reference. By choosing a threshold, for detecting pulses, as a fraction (4%) of the maximum amplitude, the systolic blood pressure was underestimated (-0.57 mmHg, SD 12.1). The range of systolic pressure for the patients was 95.5 - 199.0 mmHg, n=14. The method is promising, but improvements still have to be made in order to improve the technique.

  4. Systolic Peak Detection in Acceleration Photoplethysmograms Measured from Emergency Responders in Tropical Conditions

    PubMed Central

    Elgendi, Mohamed; Norton, Ian; Brearley, Matt; Abbott, Derek; Schuurmans, Dale

    2013-01-01

    Photoplethysmogram (PPG) monitoring is not only essential for critically ill patients in hospitals or at home, but also for those undergoing exercise testing. However, processing PPG signals measured after exercise is challenging, especially if the environment is hot and humid. In this paper, we propose a novel algorithm that can detect systolic peaks under challenging conditions, as in the case of emergency responders in tropical conditions. Accurate systolic-peak detection is an important first step for the analysis of heart rate variability. Algorithms based on local maxima-minima, first-derivative, and slope sum are evaluated, and a new algorithm is introduced to improve the detection rate. With 40 healthy subjects, the new algorithm demonstrates the highest overall detection accuracy (99.84% sensitivity, 99.89% positive predictivity). Existing algorithms, such as Billauer's, Li's and Zong's, have comparable although lower accuracy. However, the proposed algorithm presents an advantage for real-time applications by avoiding human intervention in threshold determination. For best performance, we show that a combination of two event-related moving averages with an offset threshold has an advantage in detecting systolic peaks, even in heat-stressed PPG signals. PMID:24167546

  5. Left Ventricular Systolic Function Changes in Primary Hypertension Patients Detected by the Strain of Different Myocardium Layers

    PubMed Central

    Huang, Jun; Yan, Zi-Ning; Rui, Yi-Fei; Fan, Li; Shen, Dan; Chen, Dong-Liang

    2016-01-01

    Abstract This study investigated left ventricular (LV) systolic dysfunction associated with differential strain among myocardial layers in primary hypertension (PH) patients with or without LV hypertrophy (LVH), and normal patients. In 63 PH and 42 healthy patients, two-dimensional speckle tracking echocardiography was used to measure the peak systolic longitudinal and circumferential strain of the myocardial subendocardial, middle and subepicardial layers, and the peak systolic radial strain. To assess LV systolic function, the apical long axis, 4- and 2-chamber views, and parasternal short axis at the basal, middle, and apical levels were acquired by cardiovascular ultrasound (Vivid E9, GE Healthcare, USA). Overall, the pattern in peak systolic longitudinal strain among myocardial layers was subendocardial > middle > subepicardial. In the peak systolic circumferential strain, this was middle > subepicardial > subendocardial. The peak systolic longitudinal strain was normal > NLVH > LVH. Among the groups, the peak systolic circumferential strain at the basal parasternal short-axis level was statistically similar, but at the middle and the apical parasternal short-axis levels were NLVH > normal > LVH. In normal and NLVH patients, the peak radial strain was middle > apical > basal, and in LVH patients was apical > middle > basal. The peak averages of the longitudinal and subendocardial circumferential strains differed significantly when LVH compared with NLVH and normal patients. The systolic function of PH patients was damaged in comparison with normal individuals, which could be detected conveniently and accurately using two-dimensional speckle tracking echocardiography. PMID:26765428

  6. Late Systolic Central Hypertension as a Predictor of Incident Heart Failure: The Multi‐Ethnic Study of Atherosclerosis

    PubMed Central

    Chirinos, Julio A.; Segers, Patrick; Duprez, Daniel A.; Brumback, Lyndia; Bluemke, David A.; Zamani, Payman; Kronmal, Richard; Vaidya, Dhananjay; Ouyang, Pamela; Townsend, Raymond R.; Jacobs, David R.

    2015-01-01

    Background Experimental studies demonstrate that high aortic pressure in late systole relative to early systole causes greater myocardial remodeling and dysfunction, for any given absolute peak systolic pressure. Methods and Results We tested the hypothesis that late systolic hypertension, defined as the ratio of late (last one third of systole) to early (first two thirds of systole) pressure–time integrals (PTI) of the aortic pressure waveform, independently predicts incident heart failure (HF) in the general population. Aortic pressure waveforms were derived from a generalized transfer function applied to the radial pressure waveform recorded noninvasively from 6124 adults. The late/early systolic PTI ratio (L/ESPTI) was assessed as a predictor of incident HF during median 8.5 years of follow‐up. The L/ESPTI was predictive of incident HF (hazard ratio per 1% increase=1.22; 95% CI=1.15 to 1.29; P<0.0001) even after adjustment for established risk factors for HF (HR=1.23; 95% CI=1.14 to 1.32: P<0.0001). In a multivariate model that included brachial systolic and diastolic blood pressure and other standard risk factors of HF, L/ESPTI was the modifiable factor associated with the greatest improvements in model performance. A high L/ESPTI (>58.38%) was more predictive of HF than the presence of hypertension. After adjustment for each other and various predictors of HF, the HR associated with hypertension was 1.39 (95% CI=0.86 to 2.23; P=0.18), whereas the HR associated with a high L/E was 2.31 (95% CI=1.52 to 3.49; P<0.0001). Conclusions Independently of the absolute level of peak pressure, late systolic hypertension is strongly associated with incident HF in the general population. PMID:25736440

  7. [Baroreflex and blood pressure variations in borderline hypertension of the young adult].

    PubMed

    Chanudet, X; Chau, N P; Hoffman, O; Fassa, Y; Clément, R; Garcin, J M; Larroque, P

    1991-08-01

    Blood pressure (BP) variability depends on external and internal factors. Among these, arterial baroreflex play an important role. The matter of this study is to assess the relationship between these two parameters in borderline hypertension (BL). Twenty six BL male hypertensive were recruited for the study, all gave informed consent. Age: 21 +/- 2 years, height: 177 +/- 8 cm, weight: 77 +/- 14 kg. An ambulatory BP monitoring was performed in each one using a Diasys (Novacor) recorder. Measurements were obtained each 15 minutes for 24 hours. Mean, standard deviation and variation coefficient (VC) of BP and heart rate (HR) were computed for 24 hours, daytime (9a.m.-7 p.m.), nighttime (11 p.m.-7 a.m.). Baroreflex sensitivity (BRS) was determined as the ratio of HR variation on systolic BP variation recorded with a Finapres device from the fourth phase of a Valsalva manoeuvre. Mean systolic and diastolic BP values for 24 hours, daytime and nighttime are: 129 +/- 11/73 +/- 13, 137 +/- 14/76 +/- 15, 114 +/- 11/69 +/- 12 mmHg. VC are: 12 +/- 3/15 +/- 3, 9 +/- 3/13 +/- 3, 10 +/- 3/13 +/- 4%. HR values are: 73 +/- 10, 84 +/- 14, 58 +/- 7 b/min, VC are: 24 +/- 5, 17 +/- 4, 17 +/- 7%. Index for BRS = 1.76 +/- 0.65%. There is no correlation between BRS and systolic BP or HR. BRS is correlated to the inverse of systolic daytime BP VC: r = -0.556, p = 0.003. There is no correlation with other parameters. This study provides evidence for a link between BRS and daytime BP variability in borderline hypertension. PMID:1953260

  8. Left ventricular systolic intraventricular flow field assessment in hyperthyroidism patients using vector flow mapping.

    PubMed

    Zhou, Bin-Yu; Wang, Jing; Xie, Ming-Xing; Liu, Man-Wei; Lv, Qing

    2015-08-01

    Intraventricular hydrodynamics is considered an important component of cardiac function assessment. Vector flow mapping (VFM) is a novel flow visualization method to describe cardiac pathophysiological condition. This study examined use of new VFM and flow field for assessment of left ventricular (LV) systolic hemodynamics in patients with simple hyperthyroidism (HT). Thirty-seven simple HT patients were enrolled as HT group, and 38 gender- and age-matched healthy volunteers as control group. VFM model was used to analyze LV flow field at LV apical long-axis view. The following flow parameters were measured, including peak systolic velocity (Vs), peak systolic flow (Fs), total systolic negative flow (SQ) in LV basal, middle and apical level, velocity gradient from the apex to the aortic valve (ΔV), and velocity according to half distance (V1/2). The velocity vector in the LV cavity, stream line and vortex distribution in the two groups were observed. The results showed that there were no significant differences in the conventional parameters such as left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD) and left atrium diameter (LAD) between HT group and control group (P>0.05). Compared with the control group, a brighter flow and more vortexes were detected in HT group. Non-uniform distribution occurred in the LV flow field, and the stream lines were discontinuous in HT group. The values of Vs and Fs in three levels, SQ in middle and basal levels, ΔV and V1/2 were higher in HT group than in control group (P<0.01). ΔV was positively correlated with serum free thyroxin (FT4) (r=0.48, P<0.01). Stepwise multiple regression analysis showed that LVEDD, FT4, and body surface area (BSA) were the influence factors of ΔV. The unstable left ventricular systolic hydrodynamics increased in a compensatory manner in simple HT patients. The present study indicated that VFM may be used for early detection of abnormal ventricle contraction in

  9. Cytochrome P450 (CYP2D6) Genotype is Associated with Elevated Systolic Blood Pressure in Preterm Infants Following NICU Discharge

    PubMed Central

    Dagle, John M; Fisher, Tyler J; Haynes, Susan E; Berends, Susan K; Brophy, Patrick D; Morriss, Frank H; Murray, Jeffrey C

    2011-01-01

    Objective To determine genetic and clinical risk factors associated with elevated systolic blood pressure (ESBP) in preterm infants following discharge. Study design A convenience cohort of infants <32 weeks gestational age was followed after discharge; we retrospectively identified a subgroup of subjects with ESBP (SBP > 90th percentile for term infants). Genetic testing identified alleles associated with ESBP. Multivariable logistic regression analysis was performed for the outcome ESBP with clinical characteristics and genotype as independent variables. Results Predictors of ESBP were: CYP2D6 (rs28360521) CC genotype (OR 2.92; 95% CI 1.48, 5.79), adjusted for outpatient oxygen therapy (OR 4.53, 95%CI 2.23, 8.81) and history of urinary tract infection (OR 4.68, 95% CI 1.47, 14.86). Maximum SBP was modeled by multivariable linear regression analysis: Maximum SBP = 84.8 mmHg + 6.8 mmHg (if CYP2D6 CC genotype) + 6.8 mmHg (if discharged on supplemental oxygen) + 4.4 mmHg (if received inpatient glucocorticoids) (p=0.0002). Conclusion ESBP is common among preterm infants with residual lung disease following NICU discharge. This study reveals clinical factors associated with ESBP, identifies a candidate gene for further testing, and supports the recommendation that BP be monitored sooner than at age 3 years as suggested for term infants. PMID:21353244

  10. Systolic architectures for the computation of the discrete Hartley and the discrete cosine transforms based on prime factor decomposition

    SciTech Connect

    Chakrabarti, C. . Dept. of Electrical Engineering); Ja Ja, J. . Dept. of Electrical Engineering)

    1990-11-01

    This paper proposes two-dimensional systolic array implementations for computing the discrete Hartley (DHT) and the discrete cosine transforms (DCT) when the transform size N is decomposable into mutually prime factors. The existing two-dimensional formulations for DHT and DCT are modified and the corresponding algorithms are mapped into two-dimensional systolic arrays. The resulting architecture is fully pipelined with no control units. The hardware design is based on bit serial left to right MSB to LSB binary arithmetic.

  11. NOSC (Naval Ocean Systems Center) advanced systolic array processor (ASAP). Professional paper for period ending August 1987

    SciTech Connect

    Loughlin, J.P.

    1987-12-01

    Design of a high-speed (250 million 32-bit floating-point operations per second) two-dimensional systolic array composed of 16-bit/slice microsequencer structured processors is presented. System-design features such as broadcast data flow, tag bit movement, and integrated diagnostic test registers are described. The software development tools needed to map complex matrix-based signal-processing algorithms onto the systolic-processor system are described.

  12. A new dynamic myocardial phantom for evaluation of SPECT and PET quantitation in systolic and diastolic conditions

    SciTech Connect

    Dreuille, O. de; Bendriem, B.; Riddell, C.

    1996-12-31

    We present a new dynamic myocardial phantom designed to evaluate SPECT and PET imaging in systolic and diastolic conditions. The phantom includes a thoracic attenuating media and the myocardial wall thickness varying during the scan can be performed. In this study the phantom was used with three different wall thickness characteristic of a systolic, end-diastolic and pathologic end-diastolic condition. The myocardium was filled with {sup 99m}Tc, {sup 18}F and Gd and imaged by SPECT, PET and MRI. SPECT attenuation correction was performed using a modified PET transmission. A bull`s eyes image was obtained for all data and wall ROI were then drawn for analysis. Using MRI as a reference, error from PET, SPECT and attenuation corrected SPECT were calculated. Systolic PET performances agree with MRI. Quantitation loss due to wall thickness reduction compared to the systole. Attenuation correction in SPECT leads to significant decrease of the error both in systole (from 29% to 14%) and diastole (35% to 22%). This is particularly sensitive for septum and inferior walls. SPECT residual errors (14% in systole and 22% in pathologic end-diastole) are likely caused by scatter, noise and depth dependent resolution effect. The results obtained with this dynamical phantom demonstrate the quantitation improvement achieved in SPECT with attenuation correction and also reinforce the need for variable resolution correction in addition to attenuation correction.

  13. Left ventricular systolic function during stress echocardiography exercise in subjects with asymptomatic hereditary hemochromatosis.

    PubMed

    Shizukuda, Yukitaka; Bolan, Charles D; Tripodi, Dorothy J; Yau, Yu-Ying; Smith, Kevin P; Sachdev, Vandana; Birdsall, Charles W; Sidenko, Stanislav; Waclawiw, Myron A; Leitman, Susan F; Rosing, Douglas R

    2006-09-01

    There is no information available on left ventricular (LV) systolic function and the response to stress echocardiography in asymptomatic subjects with hereditary hemochromatosis (HH). To evaluate this topic, 43 asymptomatic subjects with HH homozygous for the C282Y HFE gene mutation (22 untreated subjects [group A] and 21 long-term treated subjects [group B]) were compared with 21 age- and gender-matched normal volunteers negative for HFE mutations. Contractile reserve, as a measure of LV systolic function, was assessed using continuous echocardiographic imaging and electrocardiography during supine bicycle exercise. Nineteen subjects in group A had repeat tests after 6 months of induction phlebotomy therapy to assess the effect of iron removal. Exercise performance and hemodynamic variables of supine bicycle exercise were comparable between subjects with HH and controls. LV contractile reserve of asymptomatic subjects with HH was not impaired at either a 75-W submaximal exercise level (mean +/- SD difference in ejection fraction from baseline 13.8 +/- 6.2%, 11.5 +/- 6.8%, and 13.4 +/- 7.8% in groups A, B, and C, respectively; p = NS for all by analysis of variance) or at peak exercise (difference in ejection fraction from baseline 18.9 +/- 6.9%, 18.4 +/- 7.8%, and 20.3 +/- 8.1% in groups A, B, and C, respectively; p = NS for all by analysis of variance). However, the incidence of abnormal ischemic stress electrocardiographic responses was more frequent in subjects with HH as a whole (33%) compared with normal subjects (10%). Stress imaging revealed no regional wall motion abnormalities, suggesting that these were false-positive results. Iron removal by induction phlebotomy did not affect stress echocardiographic performance. In conclusion, LV systolic function during exercise in asymptomatic subjects with HH is preserved, and 6-month induction phlebotomy does not affect stress echocardiographic performance. PMID:16923464

  14. Clinical and Echocardiographic Factors Associated with Right Ventricular Systolic Dysfunction in Hemodialysis Patients

    PubMed Central

    López-Quijano, Juan Manuel; Gordillo-Moscoso, Antonio; Viana-Rojas, Jesús Antonio; Carrillo-Calvillo, Jorge; Mandeville, Peter B.; Chevaile-Ramos, Alejandro

    2016-01-01

    Background Chronic kidney disease is a disorder of epidemic proportions that impairs cardiac function. Cardiovascular diseases are the leading cause of death in hemodialysis patients, and the understanding of new nontraditional predictors of mortality could improve their outcomes. Right ventricular systolic dysfunction (RVSD) has recently been recognized as a predictor of cardiovascular death in heart failure and hemodialysis patients. However, the factors contributing to RVSD in hemodialysis patients remain unknown. The aim of this study was to evaluate the clinical and echocardiographic factors associated with RVSD in hemodialysis patients. Methods A cross-sectional study was conducted in which 100 outpatients with end-stage renal disease on chronic hemodialysis were evaluated. A transthoracic echocardiographic examination was performed at optimal dry weight. Right ventricular systolic function was evaluated using tricuspid annular plane systolic excursion (TAPSE). Clinical and echocardiographic data were recorded for each patient. A multivariate linear logistic regression was created using RVSD (TAPSE <14 mm) as the dependent variable. Results Fifteen patients with RVSD and 85 patients without RVSD were analyzed. TAPSE had a positive correlation with left ventricular ejection fraction (LVEF) and myocardial relaxation velocity. Independent contributors to RVSD were LVEF (OR 1.14, 95% CI 1.05-1.26), left ventricular mass index (OR 1.02, 95% CI 1.00-1.04), and myocardial relaxation velocity (OR 1.81, 95% CI 1.18-3.19). Conclusions Echocardiographic factors were significant contributors to RVSD. These measurements could be included as part of the routine workup in all end-stage renal disease patients on hemodialysis.

  15. Echocardiographic Parameters and Survival in Chagas Heart Disease with Severe Systolic Dysfunction

    PubMed Central

    Rassi, Daniela do Carmo; Vieira, Marcelo Luiz Campos; Arruda, Ana Lúcia Martins; Hotta, Viviane Tiemi; Furtado, Rogério Gomes; Rassi, Danilo Teixeira; Rassi, Salvador

    2014-01-01

    Background Echocardiography provides important information on the cardiac evaluation of patients with heart failure. The identification of echocardiographic parameters in severe Chagas heart disease would help implement treatment and assess prognosis. Objective To correlate echocardiographic parameters with the endpoint cardiovascular mortality in patients with ejection fraction < 35%. Methods Study with retrospective analysis of pre-specified echocardiographic parameters prospectively collected from 60 patients included in the Multicenter Randomized Trial of Cell Therapy in Patients with Heart Diseases (Estudo Multicêntrico Randomizado de Terapia Celular em Cardiopatias) - Chagas heart disease arm. The following parameters were collected: left ventricular systolic and diastolic diameters and volumes; ejection fraction; left atrial diameter; left atrial volume; indexed left atrial volume; systolic pulmonary artery pressure; integral of the aortic flow velocity; myocardial performance index; rate of increase of left ventricular pressure; isovolumic relaxation time; E, A, Em, Am and Sm wave velocities; E wave deceleration time; E/A and E/Em ratios; and mitral regurgitation. Results In the mean 24.18-month follow-up, 27 patients died. The mean ejection fraction was 26.6 ± 5.34%. In the multivariate analysis, the parameters ejection fraction (HR = 1.114; p = 0.3704), indexed left atrial volume (HR = 1.033; p < 0.0001) and E/Em ratio (HR = 0.95; p = 0.1261) were excluded. The indexed left atrial volume was an independent predictor in relation to the endpoint, and values > 70.71 mL/m2 were associated with a significant increase in mortality (log rank p < 0.0001). Conclusion The indexed left atrial volume was the only independent predictor of mortality in this population of Chagasic patients with severe systolic dysfunction. PMID:24553982

  16. Atrial systole enhances intraventricular filling flow propagation during increasing heart rate.

    PubMed

    Santhanakrishnan, Arvind; Okafor, Ikechukwu; Kumar, Gautam; Yoganathan, Ajit P

    2016-02-29

    Diastolic fluid dynamics in the left ventricle (LV) has been examined in multiple clinical studies for understanding cardiac function in healthy humans and developing diagnostic measures in disease conditions. The question of how intraventricular filling vortex flow pattern is affected by increasing heart rate (HR) is still unanswered. Previous studies on healthy subjects have shown a correlation between increasing HR and diminished E/A ratio of transmitral peak velocities during early filling (E-wave) to atrial systole (A-wave). We hypothesize that with increasing HR under constant E/A ratio, E-wave contribution to intraventricular vortex propagation is diminished. A physiologic in vitro flow phantom consisting of a LV physical model was used for this study. HR was varied across 70, 100 and 120 beats per minute (bpm) with E/A of 1.1-1.2. Intraventricular flow patterns were characterized using 2D particle image velocimetry measured across three parallel longitudinal (apical-basal) planes in the LV. A pair of counter-rotating vortices was observed during E-wave across all HRs. With increasing HR, diminished vortex propagation occurred during E-wave and atrial systole was found to amplify secondary vorticity production. The diastolic time point where peak vortex circulation occurred was delayed with increasing HR, with peak circulation for 120bpm occurring as late as 90% into diastole near the end of A-wave. The role of atrial systole is elevated for higher HR due to the limited time available for filling. Our baseline findings and analysis approach can be applied to studies of clinical conditions where impaired exercise tolerance is observed. PMID:26895781

  17. Identification of phenotypes at risk of transition from diastolic hypertension to isolated systolic hypertension.

    PubMed

    Esposito, R; Izzo, R; Galderisi, M; De Marco, M; Stabile, E; Esposito, G; Trimarco, V; Rozza, F; De Luca, N; de Simone, G

    2016-06-01

    Little is known about the potential progression of hypertensive patients towards isolated systolic hypertension (ISH) and about the phenotypes associated with the development of this condition. Aim of this study was to detect predictors of evolution towards ISH in patients with initial systolic-diastolic hypertension. We selected 7801 hypertensive patients free of prevalent cardiovascular (CV) diseases or severe chronic kidney disease and with at least 6-month follow-up from the Campania Salute Network. During 55±44 months of follow-up, incidence of ISH was 21%. Patients with ISH at the follow-up were significantly older (P<0.0001), had longer duration of hypertension, higher prevalence of diabetes and were more likely to be women (all P<0.0001). They exhibited higher baseline left ventricular mass index (LVMi), arterial stiffness (pulse pressure/stroke index), relative wall thickness (RWT) and carotid intima-media thickness (IMT; all P<0.001). Independent predictors of incident ISH were older age (odds ratio (OR)=1.14/5 years), female gender (OR=1.30), higher baseline systolic blood pressure (OR=1.03/5 mm Hg), lower diastolic blood pressure (OR=0.89/5 mm Hg), longer duration of hypertension (OR=1.08/5 months), higher LVMi (OR=1.02/5 g m(-2.7)), arterial stiffness (OR=2.01), RWT (OR=1.02), IMT (OR=1.19 mm(-1); all P<0.0001), independently of antihypertensive treatment, obesity, diabetes and fasting glucose (P>0.05). Our findings suggest that ISH is a sign of aggravation of the atherosclerotic disease already evident by the target organ damage. Great efforts should be paid to prevent this evolution and prompt aggressive therapy for arterial hypertension should be issued before the onset of target organ damage, to reduce global CV risk. PMID:26355832

  18. Ambulatory monitoring detects sorafenib-induced blood pressure elevations on the first day of treatment

    PubMed Central

    Maitland, Michael L.; Kasza, Kristen E.; Karrison, Theodore; Moshier, Kristin; Sit, Laura; Black, Henry R.; Undevia, Samir D.; Stadler, Walter M.; Elliott, William J.; Ratain, Mark J.

    2009-01-01

    Purpose Hypertension is a mechanism-based toxicity of sorafenib and other cancer therapeutics that inhibit the vascular endothelial growth factor (VEGF) signaling pathway (VSP). This prospective, single center, cohort study characterized ambulatory blood pressure (BP) monitoring (ABPM) as an early pharmacodynamic biomarker of VSP inhibition by sorafenib. Experimental Design Fifty-four normotensive advanced cancer patients underwent 24-hour ABPM prior to and between days 6 and 10 of sorafenib therapy. After BP changes were detected among the first cohort within 10 days, ABPM was performed during the first 24 hours of treatment for the second cohort. Results For the entire patient population the BP increase (mean systolic +10.8 mmHg [95% CI, 8.6 to 13.0], range −5.2 to +28.7 mmHg; mean diastolic +8.0 mmHg [95% CI, 6.3 to 9.7], range −4.4 to +27.1mmHg) was detected between days 6 and 10 (P <0.0001 for both) and plateaued thereafter. Variability in BP change did not associate with: age, body size, sex, self-reported race, baseline BP, or steady state sorafenib plasma concentrations. In the second cohort the BP elevation was detected during the first 24 hours (mean systolic +8.2 mmHg [95% CI, 5.0 to 11.3]; mean diastolic +6.5 mmHg [95% CI, 4.7 to 8.3] P <0.0001 for both). Conclusions ABPM detects the BP response to VSP inhibition by sorafenib during the first 24 hours of treatment. The magnitude of BP elevation is highly variable and unpredictable, but could be important in optimizing the therapeutic index of VSP inhibitor therapy. PMID:19773379

  19. Trailer siting issues: BP Texas City.

    PubMed

    Kaszniak, Mark; Holmstrom, Donald

    2008-11-15

    On 23 March, 2005, a series of explosions and fires occurred at the BP Texas City refinery during the startup of an isomerization (ISOM) process unit. Fifteen workers were killed and about 180 others were injured. All of the fatalities were contract workers; the deaths and most of the serious injuries occurred in and around temporary office trailers that had been sited near a blowdown drum and stack open to the atmosphere as part of ongoing turnaround activities in an adjacent unit. Due to problems that developed during the ISOM startup, flammable hydrocarbon liquid overfilled the blowdown drum and stack which resulted in a geyser-like release out the top into the atmosphere. The flammable hydrocarbons fell to the ground releasing vapors that were likely ignited from a nearby idling diesel pickup truck. A total of 44 trailers were damaged by the blast pressure wave that propagated through the refinery when the vapor cloud exploded. Thirteen trailers were totally destroyed and workers were injured in trailers as far as 479ft away from the release. The focus of this paper will be on trailer siting issues, including: need for work/office trailers within process units, adequacy of risk analysis methods in API RP 752, and minimum safe distance requirements PMID:18294765

  20. Recognition of Fibrotic Infarct Density by the Pattern of Local Systolic-Diastolic Myocardial Electrical Impedance

    PubMed Central

    Amorós-Figueras, Gerard; Jorge, Esther; García-Sánchez, Tomás; Bragós, Ramón; Rosell-Ferrer, Javier; Cinca, Juan

    2016-01-01

    Myocardial electrical impedance is a biophysical property of the heart that is influenced by the intrinsic structural characteristics of the tissue. Therefore, the structural derangements elicited in a chronic myocardial infarction should cause specific changes in the local systolic-diastolic myocardial impedance, but this is not known. This study aimed to characterize the local changes of systolic-diastolic myocardial impedance in a healed myocardial infarction model. Six pigs were successfully submitted to 150 min of left anterior descending (LAD) coronary artery occlusion followed by reperfusion. 4 weeks later, myocardial impedance spectroscopy (1–1000 kHz) was measured at different infarction sites. The electrocardiogram, left ventricular (LV) pressure, LV dP/dt, and aortic blood flow (ABF) were also recorded. A total of 59 LV tissue samples were obtained and histopathological studies were performed to quantify the percentage of fibrosis. Samples were categorized as normal myocardium (<10% fibrosis), heterogeneous scar (10–50%) and dense scar (>50%). Resistivity of normal myocardium depicted phasic changes during the cardiac cycle and its amplitude markedly decreased in dense scar (18 ± 2 Ω·cm vs. 10 ± 1 Ω·cm, at 41 kHz; P < 0.001, respectively). The mean phasic resistivity decreased progressively from normal to heterogeneous and dense scar regions (285 ± 10 Ω·cm, 225 ± 25 Ω·cm, and 162 ± 6 Ω·cm, at 41 kHz; P < 0.001 respectively). Moreover, myocardial resistivity and phase angle correlated significantly with the degree of local fibrosis (resistivity: r = 0.86 at 1 kHz, P < 0.001; phase angle: r = 0.84 at 41 kHz, P < 0.001). Myocardial infarcted regions with greater fibrotic content show lower mean impedance values and more depressed systolic-diastolic dynamic impedance changes. In conclusion, this study reveals that differences in the degree of myocardial fibrosis can be detected in vivo by local measurement of phasic systolic