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1

Relation of QRS Duration to Response to Cardiac Resynchronization Therapy.  

PubMed

Left bundle branch block (LBBB) is the most reliable electrocardiographic predictor of responsiveness to cardiac resynchronization therapy (CRT). However, not all patients with LBBB will respond to CRT. Our aim was to investigate the interaction between QRS duration, LBBB-type morphology, and the responsiveness to CRT. We retrospectively analyzed electrocardiograms of 243 patients who underwent CRT implantation according to current clinical indications. A 6-month reduction of left ventricular end-systolic volume >15% was used to identify CRT responders. The clinical end point consisted of death, hospitalization for heart failure and sustained rapid ventricular tachyarrhythmias. An LBBB morphology was present in 169 patients (70%) and 101 of these (60%) were responders to CRT. Analyzing the interaction between QRS duration and CRT responsiveness in patients with LBBB, a "U shaped" distribution resulted, with nonresponders clustered between 120 and 130 ms and above 180 ms. The receiver operating characteristic curve analysis identified 178 ms as the optimal cut-off value of QRS to predict a nonresponsiveness to CRT (area under the curve = 0.67 [95% confidence interval 0.57 to 0.76]). At multivariate analysis, only an ischemic cause and a QRS ?178 ms were independent predictors of nonresponsiveness to CRT (area under the curve = 0.75). Patients with LBBB with QRS ?178 ms had greater likelihood of adverse clinical events during a mean follow-up of 32 months (p = 0.049). In conclusion, in patients with LBBB undergoing CRT, a marked QRS widening (i.e., ?178 ms) is related to worse echocardiographic responsiveness and lower event free survival rate compared with patients with an intermediate QRS widening. PMID:25465934

Sassone, Biagio; Gambetti, Simona; Bertini, Matteo; Beltrami, Matteo; Mascioli, Giosuè; Bressan, Sabrina; Fucà, Giuseppe; Pacchioni, Federico; Pedaci, Mario; Michelotti, Federica; Bacchi Reggiani, Maria Letizia; Padeletti, Luigi

2015-01-15

2

Electrocardiographic QRS Duration and the Risk of Congestive Heart Failure The Framingham Heart Study  

Microsoft Academic Search

Prolonged electrocardiographic QRS duration is frequently observed in congestive heart failure (CHF) patients. We hypothesized that CHF risk increases with longer QRS interval in individuals free of CHF. We evaluated 1759 Framingham Study participants (mean age, 69 years; 63% women) without prior myocardial infarction or CHF who attended a routine examination. QRS duration was analyzed as a continuous (log-transformed) and

Ravi Dhingra; Michael J. Pencina; Thomas J. Wang; Byung-Ho Nam; Emelia J. Benjamin; Daniel Levy; Martin G. Larson; William B. Kannel; Ralph B. D'Agostino; Ramachandran S. Vasan

3

Assessment of Left Ventricular Dyssynchrony in Heart Failure Patients Regarding Underlying Etiology and QRS Duration  

PubMed Central

Background: Left ventricular (LV) dyssynchrony is a prevalent feature in heart failure (HF) patients. The current study aimed to evaluate the prevalence of inter and intraventricular dyssynchrony in HF patients with regard to the QRS duration and etiology. Methods: The available data on the tissue Doppler imaging (TDI) of 230 patients with refractory HF were analyzed. The patients were divided into three groups according to the QRS duration: QRS duration < 120 ms; 120–150 ms; and ? 150 ms and the patients were re-categorized into two subgroups depending on the underlying etiology: ischemic cardiomyopathy (ICM) or dilated cardiomyopathy (DCM). The time-to-peak myocardial sustained systolic velocity (Ts) in six basal and six middle segments of the LV was measured manually using the velocity curves from TDI. LV dyssynchrony was defined as interventricular mechanical delay ? 40 ms and tissue Doppler velocity all segments delay ? 105 ms; standard deviation (SD) of all segments ? 34.4 ms; basal segments delay ? 78 ms; SD of basal segments ? 34.5 ms; and opposing wall delay ? 65 ms. Results: After adjustment for the possible confounders, interventricular dyssynchrony was more prevalent in the patients with QRS duration ? 150 ms than in those with QRS duration 120–150 ms and < 120 ms. The patients with DCM also had a higher percentage of interventricular dyssynchrony than those with ICM in the wide QRS groups. Turning to the intraventricular dyssynchrony indices, the patients with QRS duration ? 150 ms and 120–150 ms revealed a significantly greater delay between Ts at the basal and all segments than did those with QRS duration < 120 ms, while etiology did not influence the frequency of these indices in each QRS group. Conclusion: The prevalence of both inter and intraventricular dyssynchrony indices was greater in the patients with wide QRS than in those with narrow QRS duration. The underlying etiology may affect the frequency of interventricular but not intraventricular dyssynchrony indices. PMID:23074368

Montazeri, Mahdi; Rezvanfard, Mehrnaz; Kazemisaeid, Ali; Lotfi Tokaldany, Masoumeh; Mardanloo, Azam Safir; Darabi, Farzad; Fathollahi, Mahmood Sheikh; Sadeghian, Hakimeh

2011-01-01

4

Detecting drug-induced prolongation of the QRS complex: New insights for cardiac safety assessment  

SciTech Connect

Background: Drugs slowing the conduction of the cardiac action potential and prolonging QRS complex duration by blocking the sodium current (I{sub Na}) may carry pro-arrhythmic risks. Due to the frequency-dependent block of I{sub Na}, this study assesses whether activity-related spontaneous increases in heart rate (HR) occurring during standard dog telemetry studies can be used to optimise the detection of class I antiarrhythmic-induced QRS prolongation. Methods: Telemetered dogs were orally dosed with quinidine (class Ia), mexiletine (class Ib) or flecainide (class Ic). QRS duration was determined standardly (5 beats averaged at rest) but also prior to and at the plateau of each acute increase in HR (3 beats averaged at steady state), and averaged over 1 h period from 1 h pre-dose to 5 h post-dose. Results: Compared to time-matched vehicle, at rest, only quinidine and flecainide induced increases in QRS duration (E{sub max} 13% and 20% respectively, P < 0.01–0.001) whereas mexiletine had no effect. Importantly, the increase in QRS duration was enhanced at peak HR with an additional effect of + 0.7 ± 0.5 ms (quinidine, NS), + 1.8 ± 0.8 ms (mexiletine, P < 0.05) and + 2.8 ± 0.8 ms (flecainide, P < 0.01) (calculated as QRS at basal HR-QRS at high HR). Conclusion: Electrocardiogram recordings during elevated HR, not considered during routine analysis optimised for detecting QT prolongation, can be used to sensitise the detection of QRS prolongation. This could prove useful when borderline QRS effects are detected. Analysing during acute increases in HR could also be useful for detecting drug-induced effects on other aspects of cardiac function. -- Highlights: ? We aimed to improve detection of drug-induced QRS prolongation in safety screening. ? We used telemetered dogs to test class I antiarrhythmics at low and high heart rate. ? At low heart rate only quinidine and flecainide induced an increase in QRS duration. ? At high heart rate the effects of two out of three antiarrhythmics were enhanced. ? Detection of a drug-induced prolongation of QRS was improved at high heart rate.

Cros, C., E-mail: caroline.cros@hotmail.co.uk [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom); Skinner, M., E-mail: Matthew.Skinner@astrazeneca.com [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom); Moors, J. [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom)] [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom); Lainee, P. [Sanofi-Aventis R and D, 371, rue du Pr Joseph Blayac, 34184 Montpellier Cedex 04 (France)] [Sanofi-Aventis R and D, 371, rue du Pr Joseph Blayac, 34184 Montpellier Cedex 04 (France); Valentin, J.P. [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom)] [Safety Pharmacology, Global Safety Assessment, Safety Assessment UK, AstraZeneca R and D, Alderley Park, Macclesfield, SK10 4TG (United Kingdom)

2012-12-01

5

The value of electrocardiography for differential diagnosis in wide QRS complex tachycardia.  

PubMed

Correct diagnosis in wide QRS complex tachycardia remains a challenge. Differential diagnosis between ventricular and supraventricular tachycardia has important therapeutic and prognostic implications, and although data from clinical history and physical examination may suggest a particular origin, it is the 12-lead surface electrocardiogram that usually enables this differentiation. Since 1978, various electrocardiographic criteria have been proposed for the differential diagnosis of wide complex tachycardias, particularly the presence of atrioventricular dissociation, and the axis, duration and morphology of QRS complexes. Despite the wide variety of criteria, diagnosis is still often difficult, and errors can have serious consequences. To reduce such errors, several differential diagnosis algorithms have been proposed since 1991. However, in a small percentage of wide QRS tachycardias the diagnosis remains uncertain and in these the wisest decision is to treat them as ventricular tachycardias. The authors' objective was to review the main electrocardiographic criteria and differential diagnosis algorithms of wide QRS tachycardia. PMID:24656320

Sousa, Pedro A; Pereira, Salomé; Candeias, Rui; de Jesus, Ilídio

2014-03-01

6

The Selvester QRS Score is More Accurate than Q Waves and Fragmented QRS Complexes Using the Mason-Likar Configuration in Estimating Infarct Volume in Patients with Ischemic Cardiomyopathy  

PubMed Central

Infarct volume independently predicts cardiovascular events. Fragmented QRS complexes (fQRS) may complement Q-waves for identifying infarction; however, their utility in advanced coronary disease is unknown. We tested whether fQRS could improve the ECG prediction of infarct volume by PET in 138 patients with ischemic cardiomyopathy (EF 0.27±0.09). Indices of infarction (pathologic Q-waves, fQRS, and Selvester QRS Score) were analyzed by blinded observers. In patients with QRS duration <120ms, number of leads with pathologic Q-waves (mean 1.6±1.7) correlated weakly with infarct volume (r=0.30, p<0.05). Adding fQRS increased the number of affected leads (3.6±2.5), but the significant correlation with infarct volume was lost (r=0.02, p=0.10). Selvester Score was the most accurate (mean 5.9±4.9 points; r=0.49, p<0.001). fQRS was not predictive of infarct size in patients with QRS duration ?120ms (r=0.02, p=0.19). Thus in ischemic cardiomyopathy, consideration of fQRS complexes does not improve Q-wave prediction of infarct volume, but Selvester Score was more accurate. PMID:20381066

Carey, Mary G.; Luisi, Andrew J.; Baldwa, Sunil; Al-Zaiti, Salah; Veneziano, Marc J.; deKemp, Robert A.; Canty, John M.; Fallavollita, James A.

2010-01-01

7

T-wave inversion, QRS duration, and QRS/T angle as electrocardiographic predictors of the risk for sudden cardiac death.  

PubMed

The aim of this study was to investigate the prognostic utility of isolated T-wave inversion (TWI), QRS duration, and QRS/T angle on electrocardiogram at rest as predictors for sudden cardiac death (SCD) and death from all causes. The assessment of electrocardiographic findings was based on a population-based cohort of 1,951 men (age 42 to 61 years) with a follow-up period of 20 years. Isolated TWI in the absence of ST depression, bundle branch block or major arrhythmias, prolonged QRS duration from 110 to 119 ms, and a wide QRS/T angle of >67° were identified from the 12-lead electrocardiograms. SCD was observed in 171 men (8.3%) during the follow-up. As a single electrocardiographic parameter, TWI (prevalence 2.4%) was associated with an increased risk of SCD (hazard ratio [HR] 3.30, 95% confidence interval [CI] 1.91 to 5.71, p<0.001) after adjustment for age and clinical factors. Similarly, prolonged QRS duration and wide QRS/T angle were significantly related to the risk of SCD, with HR 1.50 (95% CI 1.08 to 2.19, p=0.017) for QRS duration and HR 3.03 (95% CI 2.23 to 4.14, p<0.001) for QRS/T angle. The integrated discrimination improvement was significant when TWI (0.014, p=0.036) or QRS/T angle (0.015, p=0.002) was added to the model with age and clinical factors. In conclusion, TWI, QRS duration, and QRS/T angle are significantly associated with the risk of SCD and death from all causes beyond conventional cardiovascular risk predictors in the general population. PMID:24513474

Laukkanen, Jari Antero; Di Angelantonio, Emanuele; Khan, Hassan; Kurl, Sudhir; Ronkainen, Kimmo; Rautaharju, Pentti

2014-04-01

8

Common variants in 22 loci are associated with QRS duration and cardiac ventricular conduction  

PubMed Central

QRS interval on the electrocardiogram reflects ventricular depolarization and conduction time, and is a risk factor for mortality, sudden death, and heart failure. We performed a genome-wide association meta-analysis in 40,407 European-descent individuals from 14 studies, with further genotyping in 7170 additional Europeans, and identified 22 loci associated with QRS duration (P < 5 × 10?8). These loci map in or near genes in pathways with established roles in ventricular conduction such as sodium channels, transcription factors, and calcium-handling proteins, but also point to novel biologic processes, such as kinase inhibitors and genes related to tumorigenesis. We demonstrate that SCN10A, a gene at our most significant locus, is expressed in the mouse ventricular conduction system, and treatment with a selective SCN10A blocker prolongs QRS duration. These findings extend our current knowledge of ventricular depolarization and conduction. PMID:21076409

Sotoodehnia, Nona; Isaacs, Aaron; de Bakker, Paul I.W.; Dörr, Marcus; Newton-Cheh, Christopher; Nolte, Ilja M.; van der Harst, Pim; Müller, Martina; Eijgelsheim, Mark; Alonso, Alvaro; Hicks, Andrew A.; Padmanabhan, Sandosh; Hayward, Caroline; Smith, Albert Vernon; Polasek, Ozren; Giovannone, Steven; Fu, Jingyuan; Magnani, Jared W.; Marciante, Kristin D.; Pfeufer, Arne; Gharib, Sina A.; Teumer, Alexander; Li, Man; Bis, Joshua C.; Rivadeneira, Fernando; Aspelund, Thor; Köttgen, Anna; Johnson, Toby; Rice, Kenneth; Sie, Mark P.S.; Wang, Amanda Ying; Klopp, Norman; Fuchsberger, Christian; Wild, Sarah H.; Leach, Irene Mateo; Estrada, Karol; Völker, Uwe; Wright, Alan F.; Asselbergs, Folkert W.; Qu, Jiaxiang; Chakravarti, Aravinda; Sinner, Moritz F.; Kors, Jan A.; Petersmann, Astrid; Harris, Tamara B.; Soliman, Elsayed Z.; Munroe, Patricia B.; Psaty, Bruce M.; Oostra, Ben A.; Cupples, L. Adrienne; Perz, Siegfried; de Boer, Rudolf A.; Uitterlinden, André G.; Vözke, Henry; Spector, Timothy D.; Liu, Fang-Yu; Boerwinkle, Eric; Dominiczak, Anna F.; Rotter, Jerome I.; van Herpen, Gé; Levy, Daniel; Wichmann, H.-Erich; van Gilst, Wiek H.; Witteman, Jacqueline C.M.; Kroemer, Heyo K.; Kao, W.H. Linda; Heckbert, Susan R.; Meitinger, Thomas; Hofman, Albert; Campbell, Harry; Folsom, Aaron R.; van Veldhuisen, Dirk J.; Schwienbacher, Christine; O’Donnell, Christopher J.; Volpato, Claudia Beu; Caulfield, Mark J.; Connell, John M.; Launer, Lenore; Lu, Xiaowen; Franke, Lude; Fehrmann, Rudolf S.N.; Meerman, Gerard te; Groen, Harry J.M.; Weersma, Rinse K.; van den Berg, Leonard H.; Wijmenga, Cisca; Ophoff, Roel A.; Navis, Gerjan; Rudan, Igor; Snieder, Harold; Wilson, James F.; Pramstaller, Peter P.; Siscovick, David S.; Wang, Thomas J.; Gudnason, Vilmundur; van Duijn, Cornelia M.; Felix, Stephan B.; Fishman, Glenn I.; Jamshidi, Yalda; Stricker, Bruno H Ch; Samani, Nilesh J.; Kääb, Stefan; Arking, Dan E.

2010-01-01

9

Several common variants modulate heart rate, PR interval and QRS duration  

Microsoft Academic Search

Electrocardiographic measures are indicative of the function of the cardiac conduction system. To search for sequence variants that modulate heart rate, PR interval and QRS duration in individuals of European descent, we performed a genome-wide association study in ?10,000 individuals and followed up the top signals in an additional ?10,000 individuals. We identified several genome-wide significant associations (with P <

Daniel F Gudbjartsson; David O Arnar; Gudmar Thorleifsson; Gudmundur Thorgeirsson; Hrafnhildur Stefansdottir; Sigurjon A Gudjonsson; Aslaug Jonasdottir; Ellisiv B Mathiesen; Inger Njølstad; Audhild Nyrnes; Tom Wilsgaard; Erin M Hald; Kristian Hveem; Camilla Stoltenberg; Maja-Lisa Løchen; Augustine Kong; Unnur Thorsteinsdottir; Hilma Holm; Kari Stefansson

2010-01-01

10

Fragmented narrow QRS complex: Predictor of left ventricular dyssynchrony in non-ischemic dilated cardiomyopathy  

PubMed Central

Background Cardiac resynchronization therapy is an important therapeutic modality in drug refractory symptomatic patients of heart failure with wide QRS (?120 ms) on electrocardiogram. However, wide QRS (considered as a marker of electrical dyssynchrony) occurs in only 30% of heart failure patients, making majority of drug refractory heart failure patients ineligible for resynchronization therapy. Significant numbers of patients with narrow QRS have echocardiographic evidence of left ventricular dyssynchrony. However, there is sparse data about additional features on the surface ECG which can predict intraventricular dyssynchrony. This study was undertaken to assess the utility of fragmented narrow QRS complex to predict significant intraventricular dyssynchrony in symptomatic patients of non-ischemic dilated cardiomyopathy. Method 100 symptomatic patients of non-ischemic dilated cardiomyopathy with narrow QRS complexes (50 each with fragmented and normal QRS) were recruited. Tissue Doppler imaging was used to assess intraventricular dyssynchrony as per ‘Yu index’. Results 78% patients (n = 39) in fQRS complex group and 14% (n = 7) in normal QRS complex group had significant intraventricular dyssynchrony (?2 = 20.61; p < 0.000005). fQRS complexes had 84.78% sensitivity, 79.62% specificity, a positive predictive value of 78% and negative predictive value of 86% to detect intraventricular dyssynchrony. fQRS also had sensitivity and specificity of 93% and 90% respectively to localize the dyssynchronous segment. Conclusion fQRS is a marker of electrical dyssynchrony, which results in significant intraventricular dyssynchrony in patients of non-ischemic dilated cardiomyopathy and a narrow QRS interval. fQRS localizes the dyssynchronous segment and might be useful in identifying patients who can benefit from cardiac resynchronization therapy. PMID:23647897

Yusuf, Jamal; Agrawal, Devendra Kumar; Mukhopadhyay, Saibal; Mehta, Vimal; Trehan, Vijay; Tyagi, Sanjay

2013-01-01

11

A novel feature extracting method of QRS complex classification for mobile ECG signals  

NASA Astrophysics Data System (ADS)

The conventional classification parameters of QRS complex suffer from larger activity rang of patients and lower signal to noise ratio in mobile cardiac telemonitoring system and can not meet the identification needs of ECG signal. Based on individual sinus heart rhythm template built with mobile ECG signals in time window, we present semblance index to extract the classification features of QRS complex precisely and expeditiously. Relative approximation r2 and absolute error r3 are used as estimating parameters of semblance between testing QRS complex and template. The evaluate parameters corresponding to QRS width and types are demonstrated to choose the proper index. The results show that 99.99 percent of the QRS complex for sinus and superventricular ECG signals can be distinguished through r2 but its average accurate ratio is only 46.16%. More than 97.84 percent of QRS complexes are identified using r3 but its accurate ratio to the sinus and superventricular is not better than r2. By the feature parameter of width, only 42.65 percent of QRS complexes are classified correctly, but its accurate ratio to the ventricular is superior to r2. To combine the respective superiority of three parameters, a nonlinear weighing computation of QRS width, r2 and r3 is introduced and the total classification accuracy up to 99.48% by combing indexes.

Zhu, Lingyun; Wang, Dong; Huang, Xianying; Wang, Yue

2007-12-01

12

[Identification of onset and offset of QRS complexes based on the characteristics of angle and amplitude].  

PubMed

In order to quickly and accurately identify the onset and offset of the QRS complex in electrocardiogram (ECG) signal with different forms, a triple local transform method was employed in the present study to detect the suspected onset and offset points of QRS. The accurate onset and offset points of QRS complexes were selected according to the rules drawn by the trial process based on the characteristics of angle and amplitude constituted within these suspected points. The method makes full advantage of the angle and amplitude characteristics of the QRS complex, by which the results can be acquired with some simple arithmetic quickly, accurately and adaptively. The method was investigated with data from the MIT-BIH arrhythmia database and satisfactory results were obtained. PMID:25219237

Li, Yang; Hong, Yue; Wang, Junjie

2014-06-01

13

Methodology for automated detection of fragmentation in QRS complex of Standard 12-lead ECG.  

PubMed

Fragmented QRS (f-QRS) has been found to have higher sensitivity and/or specificity values for several diseases including remote and acute myocardial infarction, cardiac sarcoidosis etc, compared to other conventional bio-markers viz. Q-wave, ST-elevation etc. Several of these diseases do not have a reliable bio-marker and hence, patients suffering from them have to undergo expensive and sometimes invasive tests for diagnosis viz. myocardial biopsy, cardiac catheterization etc. This paper proposes automation of fragmentation detection which will lead to a more reliable diagnosis and therapy reducing human error, time consumption and thereby alleviating the need of enormous training required for detection of fragmentation. In this paper, we propose a novel approach to detect the discontinuities present in QRS complex of standard 12-lead ECG, known as fragmented QRS, using Discrete Wavelet transform (DWT) targeting both hospital-based and remote health monitoring environments. Fragmentation Detection Algorithm (FDA) was designed and modeled using PhysioNet's PTBDB and upon reiterative refinements it successfully detected all discontinuities in the QRS complex. The QRS complexes of 31 patients obtained randomly from PhysioNet's PTBDB were examined by two experienced cardiologists and the measurements obtained were compared with the results of our proposed FDA leading to 89.8% agreement among them. PMID:24110556

Maheshwari, Sidharth; Acharyya, Amit; Puddu, Paolo Emilio; Schiariti, Michele

2013-01-01

14

Prolongation of QRS duration and axis deviation in the right bundle branch block are not markers for left ventricular systolic dysfunction  

PubMed Central

BACKGROUND: Right bundle branch block (RBBB) is not commonly associated with structural heart disease and left ventricular (LV) systolic dysfunction. The purpose of the present study was to determine whether the QRS duration and degree of right axis deviation (RAD) or left axis deviation (LAD) in patients with RBBB predicted a subset of patients with significant LV systolic dysfunction. METHODS: In the present prospective study, 75 of 200 consecutive patients with RBBB had their ejection fraction (EF) evaluated by echocardiography. The relationship among QRS duration, axis and EF was derived. RESULTS: There were no significant differences in sex and EF among the patients with a normal axis, RAD or LAD. The EFs of patients with a normal axis (n=27), RAD (n=15) and LAD (n=33) were 52±15%, 49±14% and 46±17%, respectively (P=0.35). The mean EF (46±16%) of patients with a QRS duration of 150 ms or greater (n=53) was not significantly different from the mean EF (49±18%) of patients with a QRS duration of less than 150 ms (n=22) (P=0.54). For patients with a QRS of 120 ms or greater and less than 150 ms (n=22), QRS of 150 ms or greater and 180 ms or less (n=48), and QRS of greater than 180 ms (n=5), the mean EFs were 49±18%, 47±16% and 44±7%, respectively (P=0.78). There was no significant correlation between QRS duration and EF in all patients (r=0.03, P=0.83), EF and RAD (r=0.38, P=0.16) or EF and LAD (r=0.26, P=0.14). CONCLUSIONS: In patients with RBBB, the QRS duration and axis do not have a significant relationship with EF. Furthermore, prolongation of the QRS duration (150 ms or greater) in the presence of RBBB is not a marker of significant LV systolic dysfunction. PMID:22477595

Uyguanco, Eric R; Mirandi, Anthony; Qureshi, Ghazanfar; Lazar, Jason; Chhabra, Amit; Kassotis, John

2010-01-01

15

Efficacy of isolated left ventricular and biventricular pacing is differentially associated with baseline QRS duration in chronic heart failure: a meta-analysis of randomized controlled trials.  

PubMed

Cardiac resynchronization therapy can treat chronic heart failure through either biventricular pacing (BVP) or isolated left ventricular pacing (LVP), and the efficacy is depended on QRS duration. However, the optimal therapeutic choice of pacing or how the QRS influences the efficacy remains uncertain. To investigate this uncertainty, we searched available publications in PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials databases regarding differentials in efficacy parameters between BVP and LVP. A meta-analysis of eight randomized controlled trials found that BVP and LVP were comparable with regard to quality-of-life scores, left ventricular ejection fraction, left ventricular end-systolic volume, and mortality or heart transplant rates. However, there was a significant heterogeneity among the trials in 6-min walking distances. Subsequent meta-regression indicated that the baseline QRS duration significantly correlated with the standard mean difference between BVP and LVP. As QRS duration increased, the gain in 6-min walking distance with BVP became significantly greater than that of LVP. This suggests that it is necessary to consider the QRS duration when comparing the clinical effects of BVP and LVP. PMID:24957909

Chen, Junyu; Zhuang, Xiaodong; Liao, Lizhen; Liao, Xinxue; Wang, Lichun

2015-01-01

16

An efficient unsupervised fetal QRS complex detection from abdominal maternal ECG.  

PubMed

Non-invasive fetal heart rate is of great relevance in clinical practice to monitor fetal health state during pregnancy. To date, however, despite significant advances in the field of electrocardiography, the analysis of abdominal fetal ECG is considered a challenging problem for biomedical and signal processing communities. This is mainly due to the low signal-to-noise ratio of fetal ECG and difficulties in cancellation of maternal QRS complexes, motion and electromyographic artefacts. In this paper we present an efficient unsupervised algorithm for fetal QRS complex detection from abdominal multichannel signal recordings combining ICA and maternal ECG cancelling, which outperforms each single method. The signal is first pre-processed to remove impulsive artefacts, baseline wandering and power line interference. The following steps are then applied: maternal ECG extraction through independent component analysis (ICA); maternal QRS detection; maternal ECG cancelling through weighted singular value decomposition; enhancing of fetal ECG through ICA and fetal QRS detection. We participated in the Physionet/Computing in Cardiology Challenge 2013, obtaining the top official scores of the challenge (among 53 teams of participants) of event 1 and event 2 concerning fetal heart rate and fetal interbeat intervals estimation section. The developed algorithms are released as open-source on the Physionet website. PMID:25069520

Varanini, M; Tartarisco, G; Billeci, L; Macerata, A; Pioggia, G; Balocchi, R

2014-08-01

17

QRS duration and QT interval predict mortality in hypertensive patients with left ventricular hypertrophy: the Losartan Intervention for Endpoint Reduction in Hypertension Study.  

PubMed

Left ventricular hypertrophy is a risk factor for cardiovascular mortality, including sudden cardiac death. Experimentally, left ventricular hypertrophy delays ventricular conduction and prolongs action potential duration. Electrocardiographic QRS duration and QT interval measures reflect these changes, but whether these measures can further stratify risk in patients with electrocardiographic left ventricular hypertrophy is unknown. We measured the QRS duration and QT intervals from the baseline 12-lead electrocardiograms in the Losartan Intervention For Endpoint Reduction in Hypertension (LIFE) study, which included hypertensive patients with electrocardiographic evidence of left ventricular hypertrophy randomized to either losartan-based or atenolol-based treatment to lower blood pressure. In the present study, we related study baseline electrocardiographic measures to cardiovascular and all-cause mortality. There were 5429 patients (male 45.8%; mean age 66+/-7 years) included in the present analyses. After a mean follow-up of 4.9+/-0.8 years, there were 417 deaths from all causes, including 214 cardiovascular deaths. In separate univariate Cox regression analyses, QRS duration and several QT measures were significant predictors of cardiovascular mortality and all-cause mortality. However, in multivariate Cox analyses including all electrocardiographic measures and adjusting for other risk factors as well as treatment strategy, only QRS duration and maximum rate-adjusted QT(apex) interval remained as significant independent predictors of cardiovascular (P=0.022 and P=0.037, respectively) and all-cause mortality (P=0.038 and P=0.002, respectively). In conclusion, in a hypertensive risk population identified by electrocardiographic left ventricular hypertrophy, increased QRS duration and maximum QT(apex) interval can further stratify mortality risk even in the setting of effective blood pressure-lowering treatment. PMID:15037560

Oikarinen, Lasse; Nieminen, Markku S; Viitasalo, Matti; Toivonen, Lauri; Jern, Sverker; Dahlöf, Björn; Devereux, Richard B; Okin, Peter M

2004-05-01

18

On the relationship between block of the cardiac Na+ channel and drug-induced prolongation of the QRS complex  

PubMed Central

BACKGROUND AND PURPOSE Inhibition of the human cardiac Na+ channel (hNav1.5) can prolong the QRS complex and has been associated with increased mortality in patients with underlying cardiovascular disease. The safety implications of blocking hNav1.5 channels suggest the need to test for this activity early in drug discovery in order to design out any potential liability. However, interpretation of hNav1.5 blocking potency requires knowledge of how hNav1.5 block translates into prolongation of the QRS complex. EXPERIMENTAL APPROACH We tested Class I anti-arrhythmics, other known QRS prolonging drugs and drugs not reported to prolong the QRS complex. Their block of hNav1.5 channels (as IC50 values) was measured in an automated electrophysiology-based assay. These IC50 values were compared with published reports of the corresponding unbound (free) plasma concentrations attained during clinical use (fCmax) to provide an IC50 : fCmax ratio. KEY RESULTS For 42 Class I anti-arrhythmics and other QRS prolonging drugs, 67% had IC50 : fCmax ratios <30. For 55 non-QRS prolonging drugs tested, 72% had ratios >100. Finally, we determined the relationship between the IC50 value and the free drug concentration associated with prolongation of the QRS complex in humans. For 37 drugs, QRS complex prolongation was observed at free plasma concentrations that were about 15-fold lower than the corresponding IC50 at hNav1.5 channels. CONCLUSIONS AND IMPLICATIONS A margin of 30- to 100-fold between hNav1.5 IC50 and fCmax appears to confer an acceptable degree of safety from QRS prolongation. QRS prolongation occurs on average at free plasma levels 15-fold below the IC50 at hNav1.5 channels. LINKED ARTICLE This article is commented on by Gintant et al., pp. 254–259 of this issue. To view this commentary visit http://dx.doi.org/10.1111/j.1476-5381.2011.01433.x PMID:21480866

Harmer, AR; Valentin, J-P; Pollard, CE

2011-01-01

19

QRS complex detection based on simple robust 2-D pictorial-geometrical feature.  

PubMed

In this paper a heuristic method aimed for detecting of QRS complexes without any pre-process was developed. All the methods developed in previous studies were used pre-process, the most novelty of this study was suggesting a simple method which did not need any pre-process. Toward this objective, a new simple 2-D geometrical feature space was extracted from the original electrocardiogram (ECG) signal. In this method, a sliding window was moved sample-by-sample on the pre-processed ECG signal. During each forward slide of the analysis window an artificial image was generated from the excerpted segment allocated in the window. Then, a geometrical feature extraction technique based on curve-length and angle of highest point was applied to each image for establishment of an appropriate feature space. Afterwards the K-Nearest Neighbors (KNN), Artificial Neural Network (ANN) and Adaptive Network Fuzzy Inference Systems (ANFIS) were designed and implemented to the ECG signal. The proposed methods were applied to DAY general hospital high resolution holter data. For detection of QRS complex the average values of sensitivity Se?=?99.93% and positive predictivity P+?=?99.92% were obtained. PMID:24144188

Hoseini Sabzevari, S A; Moavenian, Majid

2014-01-01

20

Fragmented QRS: What Is The Meaning?  

PubMed Central

Fragmented QRS (fQRS) is a convenient marker of myocardial scar evaluated by 12-lead electrocardiogram (ECG) recording. fQRS is defined as additional spikes within the QRS complex. In patients with CAD, fQRS was associated with myocardial scar detected by single photon emission tomography and was a predictor of cardiac events. fQRS was also a predictor of mortality and arrhythmic events in patients with reduced left ventricular function. The usefulness of fQRS for detecting myocardial scar and for identifying high-risk patients has been expanded to various cardiac diseases, such as cardiac sarcoidosis, arrhythmogenic right ventricular cardiomyopathy, acute coronary syndrome, Brugada syndrome, and acquired long QT syndrome. fQRS can be applied to patients with wide QRS complexes and is associated with myocardial scar and prognosis. Myocardial scar detected by fQRS is associated with subsequent ventricular dysfunction and heart failure and is a substrate for reentrant ventricular tachyarrhythmias. PMID:23071383

Take, Yutaka; Morita, Hiroshi

2012-01-01

21

Radial dyssynchrony assessed by cardiovascular magnetic resonance in relation to left ventricular function, myocardial scarring and QRS duration in patients with heart failure  

PubMed Central

Background Intuitively, cardiac dyssynchrony is the inevitable result of myocardial injury. We hypothezised that radial dyssynchrony reflects left ventricular remodeling, myocardial scarring, QRS duration and impaired LV function and that, accordingly, it is detectable in all patients with heart failure. Methods 225 patients with heart failure, grouped according to QRS duration of <120 ms (A, n = 75), between 120-149 ms (B, n = 75) or ?150 ms (C, n = 75), and 50 healthy controls underwent assessment of radial dyssynchrony using the cardiovascular magnetic resonance tissue synchronization index (CMR-TSI = SD of time to peak inward endocardial motion in up to 60 myocardial segments). Results Compared to 50 healthy controls (21.8 ± 6.3 ms [mean ± SD]), CMR-TSI was higher in A (74.8 ± 34.6 ms), B (92.4 ± 39.5 ms) and C (104.6 ± 45.6 ms) (all p < 0.0001). Adopting a cut-off CMR-TSI of 34.4 ms (21.8 plus 2xSD for controls) for the definition of dyssynchrony, it was present in 91% in A, 95% in B and 99% in C. Amongst patients in NYHA class III or IV, with a LVEF<35% and a QRS>120 ms, 99% had dyssynchrony. Amongst those with a QRS<120 ms, 91% had dyssynchrony. Across the study sample, CMR-TSI was related positively to left ventricular volumes (p < 0.0001) and inversely to LVEF (CMR-TSI = 178.3 e (-0.033 LVEF) ms, p < 0.0001). Conclusion Radial dyssynchrony is almost universal in patients with heart failure. This vies against the notion that a lack of response to CRT is related to a lack of dyssynchrony. PMID:19930713

2009-01-01

22

Time frequency power profile of QRS complex obtained with wavelet transform in spontaneously hypertensive rats.  

PubMed

We evaluated whether frequency analysis could detect the development of interstitial fibrosis in rats. SHR/Izm and age-matched WKY/Izm were used. Limb lead II electrocardiograms were recorded. Continuous wavelet transform (CWT) was applied for the time-frequency analysis. The integrated time-frequency power (ITFP) between QRS complexes was measured and compared between groups. The ITFP at low-frequency bands (?125Hz) was significantly higher in SHR/Izm. The percent change of ITFP showed the different patterns between groups. Prominent interstitial fibrosis with an increase in TIMP-1 mRNA expression was also observed in SHR/Izm. These results were partly reproduced in a computer simulation. PMID:22182969

Takano, Nami K; Tsutsumi, Takeshi; Suzuki, Hiroshi; Okamoto, Yoshiwo; Nakajima, Toshiaki

2012-02-01

23

Transient attenuation of the amplitude of the QRS complexes in the diagnosis of Takotsubo syndrome  

PubMed Central

Background and objectives: Currently, there are no specific diagnostic electrocardiogram (ECG) signs for Takotsubo syndrome (TTS) to differentiate it from acute coronary syndromes (ACS). Myocardial oedema has been detected by cardiac magnetic resonance imaging in patients with TTS. Recently it has been postulated that myocardial oedema may be the cause of low QRS voltage (LQRSV) in the admission ECG and attenuation of the amplitude of the QRS complexes (AAQRS) in serial ECGs, noted in a few published cases of patients with TTS. The objective of this study was to evaluate whether the admission ECG of patients with documented TTS reveals LQRSV and whether AAQRS is found when serial ECGs are compared in such patients. Methods: This study evaluated the prevalence of LQRSV in the admission ECG and AAQRS in serial ECGs in patients with TTS. ECGs of 368 patients with TTS from published reports in the international literature were evaluated for LQRSV (?5 mm in limb leads and/or ?10 mm in precordial leads) and AAQRS in serial ECGs. Results: LQRSV was seen in 91.5% of 200 patients with TTS and one ECG, with a distribution of 49.0, 42.8, 51.0, 52.0, and 46.9%, in lead aVR, and inferior, anterior, lateral, and high lateral ECG lead groups, respectively. AAQRS was seen in 93.5% of 168 patients with TTS and two or more ECGs, with a distribution of 78.3, 74.5, 60.1, 70.7, and 74.5% in lead aVR, and inferior, anterior, lateral, and high lateral ECG lead groups, respectively. Conclusions: LQRSV and AAQRS are highly prevalent ECG signs in patients with TTS, and should be useful in aiding in its diagnosis and differentiation from ACS, on first contact with the patient on admission to the hospital, and the ensuing 24 hours, in conjunction with echocardiography and coronary arteriography. PMID:24562801

2014-01-01

24

Variations of QRS Morphology in Patients with Dilated Cardiomyopathy; Clinical and Prognostic Implications  

PubMed Central

The QRS represents the simultaneous activation of the right and left ventricles, although most of the QRS waveform is derived from the larger left ventricular musculature. Although normal QRS duration is <100 millisecond (ms), its duration and shape are quite variable from patient to patient in idiopathic dilated cardiomyopathy (IDCM). Prolongation of QRS occurs in 14% to 47% of heart failure (HF) patients. Left bundle branch block (LBBB) is far more common than right bundle branch block (RBBB). Dyssynchronous left ventricular activation due to LBBB and other intraventricular conduction blocks provides the rationale for the use of cardiac resynchronization therapy with biventricular pacing in patients with IDCM. Fragmented QRS (fQRS) is a marker of depolarization abnormality and present in significant number of the patients with IDCM and narrow QRS complexes. It is associated with arrhythmic events and intraventricular dyssynchrony. The purpose of this manuscript is to present an overview on some clinical, echocardiographic and prognostic implications of various QRS morphologies in patients with IDCM. PMID:25031822

Akgun, Taylan; Kalkan, Sedat; Tigen, Mustafa Kursat

2014-01-01

25

QRS detection based on wavelet coefficients.  

PubMed

Electrocardiogram (ECG) signal processing and analysis provide crucial information about functional status of the heart. The QRS complex represents the most important component within the ECG signal. Its detection is the first step of all kinds of automatic feature extraction. QRS detector must be able to detect a large number of different QRS morphologies. This paper examines the use of wavelet detail coefficients for the accurate detection of different QRS morphologies in ECG. Our method is based on the power spectrum of QRS complexes in different energy levels since it differs from normal beats to abnormal ones. This property is used to discriminate between true beats (normal and abnormal) and false beats. Significant performance enhancement is observed when the proposed approach is tested with the MIT-BIH arrhythmia database (MITDB). The obtained results show a sensitivity of 99.64% and a positive predictivity of 99.82%. PMID:22296976

Zidelmal, Zahia; Amirou, Ahmed; Adnane, Mourad; Belouchrani, Adel

2012-09-01

26

Studies of the electrical activity of the ventricles and the origin of the QRS complex.  

PubMed

Historical events in the development of cardiac electrophysiology are described briefly. Observations before 1900 showed that electrical changes accompanied activity of muscle and nerve. Other studies showed that electrical activity of the heart produced voltage changes on the human torso. In 1903 Einthoven developed the string galvanometer which made measurement of electrocardiographic potentials much easier, more accurate and more common. The bases of understanding of arrhythmias were established by Lewis in the early 1900's. Soon thereafter Wilson devised practical and theoretical approaches to the human electrocardiogram which led to many further developments. Events before 1950 established the existence and mechanism of electrical activity in excitable cells. Studies of the origin of QRS began in about 1950, with studies of depolarization of the canine ventricle. Studies of the human ventricle followed. In the 70's it appeared possible to solve the electrocardiographic forward problem, prediction of electrocardiographic potentials from a knowledge of intracardiac events. That solution appeared possible because of new approaches to the associated physical and computational problems. Attempts to solve the forward problem at that time assumed that the cardiac generator (the boundary between resting and depolarized cells) was a uniform double layer generator. (The strength of the generator is constant everywhere along the boundary). Meanwhile physiologists and anatomists had worked out the mechanism of communication between cardiac cells. The cells are longer than they are wide, and each cell can depolarize contiguous cells. The connections between cells are predominantly at the ends of the cell and the longitudinal depolarization of a cardiac mass travels three times as fast as transverse depolarization. The generator is not uniform but is strongest parallel to the long axes of the cells. Many or most of those working in the field did not recognize the importance of the connections between cardiac cells in not only the pathway of excitation, but also the potentials produced as the cells depolarized. A number of experiments indicated that the uniform double layer assumption led to both qualitative and quantitative errors in prediction of fields generated by depolarization of cardiac muscle. These are reviewed. There are now alternatives to the uniform model which recognize the non-uniformity of the cardiac generators, particularly the axial model. The forward problem is unsolved but it appears possible that these newer models will make a solution possible. PMID:8932565

Scher, A M

1995-01-01

27

Consideration of QRS complex in addition to ST-segment abnormalities in the estimation of the "risk region" during acute anterior or inferior myocardial infarction.  

PubMed

The myocardial area at risk (MaR) is an important aspect in acute ST-elevation myocardial infarction (STEMI). It represents the myocardium at the onset of the STEMI that is ischemic and could become infarcted if no reperfusion occurs. The MaR, therefore, has clinical value because it gives an indication of the amount of myocardium that could potentially be salvaged by rapid reperfusion therapy. The most validated method for measuring the MaR is (99m)Tc-sestamibi SPECT, but this technique is not easily applied in the clinical setting. Another method that can be used for measuring the MaR is the standard ECG-based scoring system, Aldrich ST score, which is more easily applied. This ECG-based scoring system can be used to estimate the extent of acute ischemia for anterior or inferior left ventricular locations, by considering quantitative changes in the ST-segment. Deviations in the ST-segment baseline that occur following an acute coronary occlusion represent the ischemic changes in the transmurally ischemic myocardium. In most instances however, the ECG is not available at the very first moments of STEMI and as times passes the ischemic myocardium becomes necrotic with regression of the ST-segment deviation along with progressive changes of the QRS complex. Thus over the time course of the acute event, the Aldrich ST score would be expected to progressively underestimate the MaR, as was seen in studies with SPECT as gold standard; anterior STEMI (r=0.21, p=0.32) and inferior STEMI (r=0.17, p=0.36). Another standard ECG-based scoring system is the Selvester QRS score, which can be used to estimate the final infarct size by considering the quantitative changes in the QRS complex. Therefore, additional consideration of the Selvester QRS score in the acute phase could potentially provide the "component" of infarcted myocardium that is missing when the Aldrich ST score alone is used to determine the MaR in the acute phase, as was seen in studies with SPECT as gold standard: anterior STEMI (r=0.47, p=0.02) and inferior STEMI (r=0.58, p<0.001). The aim of this review will be to discuss the findings regarding the combining of the Aldrich ST score and initial Selvester QRS score in determining the MaR at the onset of the event in acute anterior or inferior ST-elevation myocardial infarction. PMID:24813354

Vervaat, F E; Bouwmeester, S; van Hellemond, I E G; Wagner, G S; Gorgels, A P M

2014-01-01

28

High Frequency QRS ECG Accurately Detects Cardiomyopathy  

NASA Technical Reports Server (NTRS)

High frequency (HF, 150-250 Hz) analysis over the entire QRS interval of the ECG is more sensitive than conventional ECG for detecting myocardial ischemia. However, the accuracy of HF QRS ECG for detecting cardiomyopathy is unknown. We obtained simultaneous resting conventional and HF QRS 12-lead ECGs in 66 patients with cardiomyopathy (EF = 23.2 plus or minus 6.l%, mean plus or minus SD) and in 66 age- and gender-matched healthy controls using PC-based ECG software recently developed at NASA. The single most accurate ECG parameter for detecting cardiomyopathy was an HF QRS morphological score that takes into consideration the total number and severity of reduced amplitude zones (RAZs) present plus the clustering of RAZs together in contiguous leads. This RAZ score had an area under the receiver operator curve (ROC) of 0.91, and was 88% sensitive, 82% specific and 85% accurate for identifying cardiomyopathy at optimum score cut-off of 140 points. Although conventional ECG parameters such as the QRS and QTc intervals were also significantly longer in patients than controls (P less than 0.001, BBBs excluded), these conventional parameters were less accurate (area under the ROC = 0.77 and 0.77, respectively) than HF QRS morphological parameters for identifying underlying cardiomyopathy. The total amplitude of the HF QRS complexes, as measured by summed root mean square voltages (RMSVs), also differed between patients and controls (33.8 plus or minus 11.5 vs. 41.5 plus or minus 13.6 mV, respectively, P less than 0.003), but this parameter was even less accurate in distinguishing the two groups (area under ROC = 0.67) than the HF QRS morphologic and conventional ECG parameters. Diagnostic accuracy was optimal (86%) when the RAZ score from the HF QRS ECG and the QTc interval from the conventional ECG were used simultaneously with cut-offs of greater than or equal to 40 points and greater than or equal to 445 ms, respectively. In conclusion 12-lead HF QRS ECG employing RAZ scoring is a simple, accurate and inexpensive screening technique for cardiomyopathy. Although HF QRS ECG is highly sensitive for cardiomyopathy, its specificity may be compromised in patients with cardiac pathologies other than cardiomyopathy, such as uncomplicated coronary artery disease or multiple coronary disease risk factors. Further studies are required to determine whether HF QRS might be useful for monitoring cardiomyopathy severity or the efficacy of therapy in a longitudinal fashion.

Schlegel, Todd T.; Arenare, Brian; Poulin, Gregory; Moser, Daniel R.; Delgado, Reynolds

2005-01-01

29

A Randomized Controlled Trial to Evaluate the Safety and Efficacy of Cardiac Contractility Modulation in Patients With Moderately Reduced Left Ventricular Ejection Fraction and a Narrow QRS Duration: Study Rationale and Design.  

PubMed

Cardiac contractility modulation (CCM) signals are nonexcitatory electrical signals delivered during the cardiac absolute refractory period that enhance the strength of cardiac muscular contraction. The FIX-HF-5 study was a prospective randomized study comparing CCM plus optimal medical therapy (OMT) to OMT alone that included 428 New York Heart Association (NYHA) functional class III or IV heart failure patients with ejection fraction (EF) ?45% according to core laboratory assessment. The study met its primary safety end point, but did not reach its primary efficacy end point: a responders analysis of changes in ventilatory anaerobic threshold (VAT). However, in a prespecified subgroup analysis, significant improvements in primary and secondary end points, including the responder VAT end point, were observed in patients with EFs ranging from 25% to 45%, who constituted about one-half of the study subjects. We therefore designed a new study to prospectively confirm the efficacy of CCM in this population. A hierarchic bayesian statistical analysis plan was developed to take advantage of the data already available from the first study. In addition, based on technical difficulties encountered in reliably quantifying VAT and the relatively large amount of nonquantifiable studies, the primary efficacy end point was changed to peak VO2, with significant measures incorporated to minimize the influence of placebo effect. In this paper, we provide the details and rationale of the FIX-HF-5C study design to study CCM plus OMT compared with OMT alone in subjects with normal QRS duration, NYHA functional class III or IV, and EF 25%-45%. This study is registered on www.clinicaltrials.gov with identifier no. NCT01381172. PMID:25285748

Abraham, William T; Lindenfeld, JoAnn; Reddy, Vivek Y; Hasenfuss, Gerd; Kuck, Karl-Heinz; Boscardin, John; Gibbons, Robert; Burkhoff, Daniel

2015-01-01

30

An automated algorithm for online detection of fragmented QRS and identification of its various morphologies  

PubMed Central

Fragmented QRS (f-QRS) has been proven to be an efficient biomarker for several diseases, including remote and acute myocardial infarction, cardiac sarcoidosis, non-ischaemic cardiomyopathy, etc. It has also been shown to have higher sensitivity and/or specificity values than the conventional markers (e.g. Q-wave, ST-elevation, etc.) which may even regress or disappear with time. Patients with such diseases have to undergo expensive and sometimes invasive tests for diagnosis. Automated detection of f-QRS followed by identification of its various morphologies in addition to the conventional ECG feature (e.g. P, QRS, T amplitude and duration, etc.) extraction will lead to a more reliable diagnosis, therapy and disease prognosis than the state-of-the-art approaches and thereby will be of significant clinical importance for both hospital-based and emerging remote health monitoring environments as well as for implanted ICD devices. An automated algorithm for detection of f-QRS from the ECG and identification of its various morphologies is proposed in this work which, to the best of our knowledge, is the first work of its kind. Using our recently proposed time–domain morphology and gradient-based ECG feature extraction algorithm, the QRS complex is extracted and discrete wavelet transform (DWT) with one level of decomposition, using the ‘Haar’ wavelet, is applied on it to detect the presence of fragmentation. Detailed DWT coefficients were observed to hypothesize the postulates of detection of all types of morphologies as reported in the literature. To model and verify the algorithm, PhysioNet's PTB database was used. Forty patients were randomly selected from the database and their ECG were examined by two experienced cardiologists and the results were compared with those obtained from the algorithm. Out of 40 patients, 31 were considered appropriate for comparison by two cardiologists, and it is shown that 334 out of 372 (89.8%) leads from the chosen 31 patients complied favourably with our proposed algorithm. The sensitivity and specificity values obtained for the detection of f-QRS were 0.897 and 0.899, respectively. Automation will speed up the detection of fragmentation, reducing the human error involved and will allow it to be implemented for hospital-based remote monitoring and ICD devices. PMID:24132202

Maheshwari, Sidharth; Acharyya, Amit; Puddu, Paolo Emilio; Mazomenos, Evangelos B.; Leekha, Gourav; Maharatna, Koushik; Schiariti, Michele

2013-01-01

31

An automated algorithm for online detection of fragmented QRS and identification of its various morphologies.  

PubMed

Fragmented QRS (f-QRS) has been proven to be an efficient biomarker for several diseases, including remote and acute myocardial infarction, cardiac sarcoidosis, non-ischaemic cardiomyopathy, etc. It has also been shown to have higher sensitivity and/or specificity values than the conventional markers (e.g. Q-wave, ST-elevation, etc.) which may even regress or disappear with time. Patients with such diseases have to undergo expensive and sometimes invasive tests for diagnosis. Automated detection of f-QRS followed by identification of its various morphologies in addition to the conventional ECG feature (e.g. P, QRS, T amplitude and duration, etc.) extraction will lead to a more reliable diagnosis, therapy and disease prognosis than the state-of-the-art approaches and thereby will be of significant clinical importance for both hospital-based and emerging remote health monitoring environments as well as for implanted ICD devices. An automated algorithm for detection of f-QRS from the ECG and identification of its various morphologies is proposed in this work which, to the best of our knowledge, is the first work of its kind. Using our recently proposed time-domain morphology and gradient-based ECG feature extraction algorithm, the QRS complex is extracted and discrete wavelet transform (DWT) with one level of decomposition, using the 'Haar' wavelet, is applied on it to detect the presence of fragmentation. Detailed DWT coefficients were observed to hypothesize the postulates of detection of all types of morphologies as reported in the literature. To model and verify the algorithm, PhysioNet's PTB database was used. Forty patients were randomly selected from the database and their ECG were examined by two experienced cardiologists and the results were compared with those obtained from the algorithm. Out of 40 patients, 31 were considered appropriate for comparison by two cardiologists, and it is shown that 334 out of 372 (89.8%) leads from the chosen 31 patients complied favourably with our proposed algorithm. The sensitivity and specificity values obtained for the detection of f-QRS were 0.897 and 0.899, respectively. Automation will speed up the detection of fragmentation, reducing the human error involved and will allow it to be implemented for hospital-based remote monitoring and ICD devices. PMID:24132202

Maheshwari, Sidharth; Acharyya, Amit; Puddu, Paolo Emilio; Mazomenos, Evangelos B; Leekha, Gourav; Maharatna, Koushik; Schiariti, Michele

2013-12-01

32

Real-time, high frequency QRS electrocardiograph  

NASA Technical Reports Server (NTRS)

Real time cardiac electrical data are received from a patient, manipulated to determine various useful aspects of the ECG signal, and displayed in real time in a useful form on a computer screen or monitor. The monitor displays the high frequency data from the QRS complex in units of microvolts, juxtaposed with a display of conventional ECG data in units of millivolts or microvolts. The high frequency data are analyzed for their root mean square (RMS) voltage values and the discrete RMS values and related parameters are displayed in real time. The high frequency data from the QRS complex are analyzed with imbedded algorithms to determine the presence or absence of reduced amplitude zones, referred to herein as RAZs. RAZs are displayed as go, no-go signals on the computer monitor. The RMS and related values of the high frequency components are displayed as time varying signals, and the presence or absence of RAZs may be similarly displayed over time.

Schlegel, Todd T. (Inventor); DePalma, Jude L. (Inventor); Moradi, Saeed (Inventor)

2006-01-01

33

An innovative approach of QRS segmentation based on first-derivative, Hilbert and Wavelet Transforms.  

PubMed

The QRS detection and segmentation processes constitute the first stages of a greater process, e.g., electrocardiogram (ECG) feature extraction. Their accuracy is a prerequisite to a satisfactory performance of the P and T wave segmentation, and also to the reliability of the heart rate variability analysis. This work presents an innovative approach of QRS detection and segmentation and the detailed results of the proposed algorithm based on First-Derivative, Hilbert and Wavelet Transforms, adaptive threshold and an approach of surface indicator. The method combines the adaptive threshold, Hilbert and Wavelet Transforms techniques, avoiding the whole ECG signal preprocessing. After each QRS detection, the computation of an indicator related to the area covered by the QRS complex envelope provides the detection of the QRS onset and offset. The QRS detection proposed technique is evaluated based on the well-known MIT-BIH Arrhythmia and QT databases, obtaining the average sensitivity of 99.15% and the positive predictability of 99.18% for the first database, and 99.75% and 99.65%, respectively, for the second one. The QRS segmentation approach is evaluated on the annotated QT database with the average segmentation errors of 2.85±9.90ms and 2.83±12.26ms for QRS onset and offset, respectively. Those results demonstrate the accuracy of the developed algorithm for a wide variety of QRS morphology and the adaptation of the algorithm parameters to the existing QRS morphological variations within a single record. PMID:22226589

Madeiro, João P V; Cortez, Paulo C; Marques, João A L; Seisdedos, Carlos R V; Sobrinho, Carlos R M R

2012-11-01

34

A new QRS detection method using wavelets and artificial neural networks.  

PubMed

We present a new method for detection and classification of QRS complexes in ECG signals using continuous wavelets and neural networks. Our wavelet method consists of four wavelet basis functions that are suitable in detection of QRS complexes within different QRS morphologies in the signal and thresholding technique for denoising and feature extraction. The results demonstrate that the proposed method is not only efficient for normal ECG signal analysis but also for various types of arrhythmic cardiac signals embedded in noise. For the classification stage, a feedforward neural network was trained with standard backpropagation algorithm. The classifier input features consisted of compact wavelet coefficients of QRS complexes that resulted in higher classification rates. We demonstrate the efficiency of our method with the average accuracy 97.2% in classification of normal and abnormal QRS complexes. PMID:20703782

Abibullaev, Berdakh; Seo, Hee Don

2011-08-01

35

[Rapid identification of QRS wave based on the moving window].  

PubMed

A fast and accurate intelligent identification is the developing trend of electrocardiogram (ECG) research. However, there are few methods by which satisfactory results could be obtained both in speed and in accuracy. A fast identification method of QRS wave was proposed based on moving window operation in this study. An 80 ms wide moving window was employed, in which simple difference and product operations were carried out with simple and less computation, and a very good inhibition of P and T waves and other noises was realized. Then the method was investigated with data from the MIT-BIH arrhythmia database with absence of digital filtering de-noising, and the identification accuracy of QRS complex reached 99.6%. The results showed that a rapid and accurate identification of QRS complex could be realized, which would meet the requirements for studying the real-time ECG monitoring equipment. PMID:24459957

Li, Yang; Hong, Yue; Tian, Shaojie

2013-10-01

36

The spatial QRS-T angle: implications in clinical practice.  

PubMed

The ventricular gradient (VG) as a concept was conceived in the 1930s and its calculation yielded information that was not otherwise obtainable. The VG was not utilized by clinicians at large because it was not easy to understand and its computation time-consuming. The contemporary spatial QRS-T angle is based on the concept of the VG and defined as its mathematical and physiological integral. Its current major clinical use is to assess the cardiac primary repolarization abnormalities in 3-dimensional spatial vectorial plans which are normally untraced in the presence of secondary electrophysiological activity in a 2-dimensional routine electrocardiogram (ECG). Currently the calculation of the spatial QRS-T angle can be easily computed on the basis of a classical ECG and contributes to localization of arrhythmogenic areas in the heart by assessing overall and local heterogeneity of the myocardial ventricular action potention duration. Recent population-based studies suggest that the spatial QRS-T angle is a dominant ECG predictor of future cardiovascular events and death and it is superior to more conventional ECG parameters. Its assessment warrants consideration for intensified primary and secondary cardiovascular prevention efforts and should be included in everyday clinical practice. This review addresses the nature and diagnostic potential of the spatial QRS-T angle. The main focus is its role in ECG assessment of dispersion of repolarization, a key factor in arrythmogeneity. PMID:23909632

Voulgari, Christina; Pagoni, Stamatina; Tesfaye, Solomon; Tentolouris, Nicholas

2013-08-01

37

QRS detection using S-Transform and Shannon energy.  

PubMed

This paper presents a novel method for QRS detection in electrocardiograms (ECG). It is based on the S-Transform, a new time frequency representation (TFR). The S-Transform provides frequency-dependent resolution while maintaining a direct relationship with the Fourier spectrum. We exploit the advantages of the S-Transform to isolate the QRS complexes in the time-frequency domain. Shannon energy of each obtained local spectrum is then computed in order to localize the R waves in the time domain. Significant performance enhancement is confirmed when the proposed approach is tested with the MIT-BIH arrhythmia database (MITDB). The obtained results show a sensitivity of 99.84%, a positive predictivity of 99.91% and an error rate of 0.25%. Furthermore, to be more convincing, the authors illustrated the detection parameters in the case of certain ECG segments with complicated patterns. PMID:24856322

Zidelmal, Z; Amirou, A; Ould-Abdeslam, D; Moukadem, A; Dieterlen, A

2014-08-01

38

QRS voltage change with adriamycin administration.  

PubMed

A decrease in the electrocardiographic limb lead QRS voltage of greater than or equal to 30% was highly correlated with the development of congestive heart failure in patients treated with adriamycin (ADM). It is felt that if a decrease in limb lead QRS voltage greater than or equal to 30% were detected in a patient receiving ADM, cardiomyopathy might be avoided or ameliorated by discontinuation of the drug. PMID:667870

Minow, R A; Benjamin, R S; Lee, E T; Gottlieb, J A

1978-06-01

39

PVC discrimination using the QRS power spectrum and self-organizing maps.  

PubMed

This paper deals with the discrimination of premature ventricular contraction (PVC) arrhythmia using the fractal behavior of the power spectrum density of the QRS complexes. The linear interpolation of the QRS complex power spectrum density in Bode diagram in two different frequency intervals gives two straight lines with two different slopes. The scatter plot of one slope versus the other shows that there exists two distinct regions which represent the normal beats and the PVC beats. Therefore the PVC beats are classified using a self-organizing map fed by the two slopes of the QRS complex power spectrum. The MIT/BIH arrhythmia database is then used to evaluate the usefulness of the proposed method in the discrimination of the premature ventricular contraction (PVC) arrhythmia. The results have indicated that the method has achieved 82.71% of sensitivity and 88.06% of specificity over 46 records from the MIT-BIH arrhythmia database. PMID:19215994

Talbi, M L; Charef, A

2009-06-01

40

QRS detection using K-Nearest Neighbor algorithm (KNN) and evaluation on standard ECG databases  

PubMed Central

The performance of computer aided ECG analysis depends on the precise and accurate delineation of QRS-complexes. This paper presents an application of K-Nearest Neighbor (KNN) algorithm as a classifier for detection of QRS-complex in ECG. The proposed algorithm is evaluated on two manually annotated standard databases such as CSE and MIT-BIH Arrhythmia database. In this work, a digital band-pass filter is used to reduce false detection caused by interference present in ECG signal and further gradient of the signal is used as a feature for QRS-detection. In addition the accuracy of KNN based classifier is largely dependent on the value of K and type of distance metric. The value of K = 3 and Euclidean distance metric has been proposed for the KNN classifier, using fivefold cross-validation. The detection rates of 99.89% and 99.81% are achieved for CSE and MIT-BIH databases respectively. The QRS detector obtained a sensitivity Se = 99.86% and specificity Sp = 99.86% for CSE database, and Se = 99.81% and Sp = 99.86% for MIT-BIH Arrhythmia database. A comparison is also made between proposed algorithm and other published work using CSE and MIT-BIH Arrhythmia databases. These results clearly establishes KNN algorithm for reliable and accurate QRS-detection.

Saini, Indu; Singh, Dilbag; Khosla, Arun

2012-01-01

41

Month-to-month and year-to-year reproducibility of high frequency QRS ECG signals  

Microsoft Academic Search

High frequency electrocardiography analyzing the entire QRS complex in the frequency range of 150 to 250 Hz may prove useful in the detection of coronary artery disease, yet the long-term stability of these waveforms has not been fully characterized. Therefore, we prospectively investigated the reproducibility of the root mean squared voltage, kurtosis, and the presence versus absence of reduced amplitude

Niles J. Batdorf; Alan H. Feiveson; Todd T. Schlegel

2004-01-01

42

Value of the Qrs-T Angle in Predicting the Induction of Ventricular Tachyarrhythmias in Patients with Chagas Disease  

PubMed Central

Background The QRS-T angle correlates with prognosis in patients with heart failure and coronary artery disease, reflected by an increase in mortality proportional to an increase in the difference between the axes of the QRS complex and T wave in the frontal plane. The value of this correlation in patients with Chagas heart disease is currently unknown. Objective Determine the correlation of the QRS-T angle and the risk of induction of ventricular tachycardia / ventricular fibrillation (VT / VF) during electrophysiological study (EPS) in patients with Chagas disease. Methods Case-control study at a tertiary center. Patients without induction of VT / VF on EPS were used as controls. The QRS-T angle was categorized as normal (0-105º), borderline (105-135º) or abnormal (135-180º). Differences between groups for continuous variables were analyzed with the t test or Mann-Whitney test, and for categorical variables with Fisher's exact test. P values < 0.05 were considered significant. Results Of 116 patients undergoing EPS, 37.9% were excluded due to incomplete information / inactive records or due to the impossibility to correctly calculate the QRS-T angle (presence of left bundle branch block and atrial fibrillation). Of 72 patients included in the study, 31 induced VT / VF on EPS. Of these, the QRS-T angle was normal in 41.9%, borderline in 12.9% and abnormal in 45.2%. Among patients without induction of VT / VF on EPS, the QRS-T angle was normal in 63.4%, borderline in 14.6% and abnormal in 17.1% (p = 0.04). When compared with patients with normal QRS-T angle, those with abnormal angle had a fourfold higher risk of inducing ventricular tachycardia / ventricular fibrillation on EPS [odds ratio (OR) 4; confidence interval (CI) 1.298-12.325; p = 0.028]. After adjustment for other variables such as age, ejection fraction (EF) and QRS size, there was a trend for the abnormal QRS-T angle to identify patients with increased risk of inducing VT / VF during EPS (OR 3.95; CI 0.99-15.82; p = 0.052). The EF also emerged as a predictor of induction of VT / VF: for each point increase in EF, there was a 4% reduction in the rate of sustained ventricular arrhythmia on EPS. Conclusions Changes in the QRS-T angle and decreases in EF were associated with an increased risk of induction of VT / VF on EPS. PMID:25590925

Zampa, Hugo Bizetto; Moreira, Dalmo AR; Ferreira Filho, Carlos Alberto Brandão; Souza, Charles Rios; Menezes, Camila Caldas; Hirata, Henrique Seichii; Armaganijan, Luciana Vidal

2014-01-01

43

Integrate and fire pulse train automaton for QRS detection.  

PubMed

Monitoring heart activity from electrocardiograms (ECG) is crucial to avoid unnecessary fatalities; therefore, detection of QRS complex is fundamental to automated ECG monitoring. Continuous, portable 24/7 ECG monitoring requires wireless technology with constraints on power, bandwidth, area, and resolution. In order to provide continuous remote monitoring of patients and fast transmission of data to medical personnel for instantaneous intervention, we propose a methodology that converts analog inputs into pulses for ultralow power implementation. The signal encoding scheme is the time-based integrate and fire (IF) sampler from which a set of signal descriptors in the pulse domain are proposed. Furthermore, a logical decision rule for QRS detection based on morphological checking is derived. The proposed decision logic depends exclusively on relational and logical operators resulting in ultrafast recognition and can be implemented using combinatorial logic hardware to guarantee power consumption orders of magnitude lower than any microprocessor device. The algorithm was evaluated using the MIT-BIH arrhythmia database and results show that our algorithm performance is comparable to the state-of-the art software-based detection. PMID:24107919

Nallathambi, Gabriel; Príncipe, José C

2014-02-01

44

A method for context-based adaptive QRS clustering in real-time.  

PubMed

Continuous follow-up of heart condition through long-term electrocardiogram monitoring is an invaluable tool for diagnosing some cardiac arrhythmias. In such context, providing tools for fast locating alterations of normal conduction patterns is mandatory and still remains an open issue. This work presents a real-time method for adaptive clustering QRS complexes from multilead ECG signals that provides the set of QRS morphologies that appear during an ECG recording. The method processes the QRS complexes sequentially, grouping them into a dynamic set of clusters based on the information content of the temporal context. The clusters are represented by templates which evolve over time and adapt to the QRS morphology changes. Rules to create, merge and remove clusters are defined along with techniques for noise detection in order to avoid their proliferation. To cope with beat misalignment, Derivative Dynamic Time Warping is used. The proposed method has been validated against the MIT-BIH Arrhythmia Database and the AHA ECG Database showing a global purity of 98.56% and 99.56%, respectively. Results show that our proposal not only provides better results than previous offline solutions but also fulfills real-time requirements. PMID:25312964

Castro, Daniel; Felix, Paulo; Presedo, Jesus

2014-10-01

45

Revisiting QRS Detection Methodologies for Portable, Wearable, Battery-Operated, and Wireless ECG Systems  

PubMed Central

Cardiovascular diseases are the number one cause of death worldwide. Currently, portable battery-operated systems such as mobile phones with wireless ECG sensors have the potential to be used in continuous cardiac function assessment that can be easily integrated into daily life. These portable point-of-care diagnostic systems can therefore help unveil and treat cardiovascular diseases. The basis for ECG analysis is a robust detection of the prominent QRS complex, as well as other ECG signal characteristics. However, it is not clear from the literature which ECG analysis algorithms are suited for an implementation on a mobile device. We investigate current QRS detection algorithms based on three assessment criteria: 1) robustness to noise, 2) parameter choice, and 3) numerical efficiency, in order to target a universal fast-robust detector. Furthermore, existing QRS detection algorithms may provide an acceptable solution only on small segments of ECG signals, within a certain amplitude range, or amid particular types of arrhythmia and/or noise. These issues are discussed in the context of a comparison with the most conventional algorithms, followed by future recommendations for developing reliable QRS detection schemes suitable for implementation on battery-operated mobile devices. PMID:24409290

Elgendi, Mohamed; Eskofier, Björn; Dokos, Socrates; Abbott, Derek

2014-01-01

46

Depolarization changes during acute myocardial ischemia by evaluation of QRS slopes: standard lead and vectorial approach.  

PubMed

Diagnosis and risk stratification of patients with acute coronary syndromes can be improved by adding information from the depolarization phase (QRS complex) to the conventionally used ST-T segment changes. In this study, ischemia-induced changes in the main three slopes of the QRS complex, upward ( ?(US)) and downward ( ?(DS) ) slopes of the R wave as well as the upward ( ?(TS)) slope of the terminal S wave, were evaluated as to represent a robust measure of pathological changes within the depolarization phase. From ECG recordings both in a resting state (control recordings) and during percutaneous coronary intervention (PCI)-induced transmural ischemia, we developed a method for quantification of ?(US), ?(DS), and ?(TS) that incorporates dynamic ECG normalization so as to improve the sensitivity in the detection of ischemia-induced changes. The same method was also applied on leads obtained by projection of QRS loops onto their dominant directions. We show that ?(US), ?(DS), and ?(TS) present high stability in the resting state, thus providing a stable reference for ischemia characterization. Maximum relative factors of change ( ?(?)) during PCI were found in leads derived from the QRS loop, reaching 10.5 and 13.7 times their normal variations in the control for ?(US) and ?(DS), respectively. For standard leads, the relative factors of change were 6.01 and 9.31. The ?(TS) index presented a similar behavior to that of ?(DS). The timing for the occurrence of significant changes in ?(US) and ?(DS) varied with lead, ranging from 30 s to 2 min after initiation of coronary occlusion. In the present ischemia model, relative ?(DS) changes were smaller than ST changes in most leads, however with only modest correlation between the two indices, suggesting they present different information about the ischemic process. We conclude that QRS slopes offer a robust tool for evaluating depolarization changes during myocardial ischemia. PMID:20840890

Romero, Daniel; Ringborn, Michael; Laguna, Pablo; Pahlm, Olle; Pueyo, Esther

2011-01-01

47

Effect of acute myocardial ischemia on different high-frequency bandwidths and temporal regions of the QRS.  

PubMed

The purpose of this study was to describe the changes in high-frequency QRS (HF-QRS) components due to myocardial ischemia provoked by prolonged artery occlusion during percutaneous coronary interventions (PCI). Signal-averaged ECGs from 69 patients were obtained during PCI procedures and comparison of high-frequency components of the QRS at different temporal regions and frequency bandwidth were performed. Continuous wavelet transform was applied to estimate the energy contents over the studied time-frequency regions. Seven frequency bands from 50 to 300 Hz, with bandwidth = 100 Hz were considered. The sum of all 12 leads energy decreased significantly (p < 0.001) from pre-PCI to PCI during both second half and total QRS complex in all frequency bands, but the main effect was found in the 200-300 Hz band. The energy changes were more marked toward higher frequency bands. The second half of QRS complex was more sensitive to changes due to myocardial ischemia. PMID:22255970

Magrans, Rudys; Gomis, Pedro; Voss, Andreas; Caminal, Pere

2011-01-01

48

Fragmented QRS and prediction of paroxysmal atrial fibrillation episodes  

PubMed Central

Objective: Prior studies have demonstrated the relationship between cardiovascular diseases and fragmented QRS (fQRS). fQRS was also associated with ventricular arrhythmias. Our objective was to find out the relationship between fQRS and paroxysmal atrial fibrillation (PAF). Method: A total of 301 patients without overt structural heart disease were prospectively included in the study. Patients were divided in to 2 groups according to presence of fQRS. Multivariate logistic regression analysis was used to assess the predictive value of fQRS for predicting PAF. Results: One hundred and three patients had fQRS. Patients with fQRS were older (53±16.8 vs 45.3±17.2, p<0.001), with larger left atrium (LA) (33.2±5.9 vs 30.1±5.9 mm, p=0.001), with thicker interventricular septum (IVS) (10.2±1.9 vs 9.5±2.3 mm, p=0.032), more diabetic (19.8 vs 10.6%, p=0.029) and have more PAF episodes (22.3 vs 4.1%, p<0.001) in comparison with patients without fQRS. fQRS was an independent predictor of detecting PAF episode (odds ratio, 9.69; 95% confidence interval, 2.46-38.15, p=0.001). Hypertension and diabetes mellitus were also predictive. Conclusion: The presence of fQRS independently predicted PAF episodes in holter monitoring (HM). Further studies are needed to clarify the clinical implications of this finding. PMID:25097533

Temiz, Ahmet; Gazi, Emine; Güngör, Ömer; Altun, Burak; Barutcu, Ahmet; Bekler, Adem; Tan, Yusuf Ziya; Ozcan, Sedat; Yener, Ali Ümit; Kurt, Tolga

2014-01-01

49

Iowa Child Care Quality Rating System: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Iowa's Child Care Quality Rating System prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile is divided into the following categories: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for Family Child Care Programs;…

Child Trends, 2010

2010-01-01

50

Illinois Quality Counts: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Illinois' Quality Counts prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for Family…

Child Trends, 2010

2010-01-01

51

Palm Beach Quality Counts: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Palm Beach's Quality Counts prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for…

Child Trends, 2010

2010-01-01

52

Vermont STep Ahead Recognition System: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Vermont's STep Ahead Recognition System (STARS) prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for All Child Care Programs;…

Child Trends, 2010

2010-01-01

53

New Hampshire Quality Rating System: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of New Hampshire's Quality Rating System prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4)…

Child Trends, 2010

2010-01-01

54

Virginia Star Quality Initiative: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Virginia's Star Quality Initiative prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators…

Child Trends, 2010

2010-01-01

55

Oregon Child Care Quality Indicators Program: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Oregon's Child Care Quality Indicators Program prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4)…

Child Trends, 2010

2010-01-01

56

Maine Quality for ME: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Maine's Quality for ME prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for Family…

Child Trends, 2010

2010-01-01

57

Miami-Dade Quality Counts: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Miami-Dade's Quality Counts prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for…

Child Trends, 2010

2010-01-01

58

Indiana Paths to Quality: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Indiana's Paths to Quality prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for…

Child Trends, 2010

2010-01-01

59

Ohio Step Up to Quality: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Ohio's Step Up to Quality prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for Family…

Child Trends, 2010

2010-01-01

60

Pennsylvania Keystone STARS: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Pennsylvania's Keystone STARS prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for…

Child Trends, 2010

2010-01-01

61

Minnesota Parent Aware: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Minnesota's Parent Aware prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for Family…

Child Trends, 2010

2010-01-01

62

Colorado Qualistar. QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Colorado's Qualistar prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for Family…

Child Trends, 2010

2010-01-01

63

Missouri Quality Rating System: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Missouri's Quality Rating System prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Indicators for…

Child Trends, 2010

2010-01-01

64

Mississippi Quality Step System: QRS Profile. The Child Care Quality Rating System (QRS)Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Mississippi's Quality Step System prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4) Application…

Child Trends, 2010

2010-01-01

65

An Improved QRS Wave Group Detection Algorithm and Matlab Implementation  

NASA Astrophysics Data System (ADS)

This paper presents an algorithm using Matlab software to detect QRS wave group of MIT-BIH ECG database. First of all the noise in ECG be Butterworth filtered, and then analysis the ECG signal based on wavelet transform to detect the parameters of the principle of singularity, more accurate detection of the QRS wave group was achieved.

Zhang, Hongjun

66

Do patients with heart failure and right bundle branch block need biventricular pacing? A case of significant QRS narrowing by right ventricular pacing alone.  

PubMed

We report the case of a 56-year-old male with ischemic cardiomyopathy, severe left ventricular dysfunction and right bundle branch block (RBBB) with a wide QRS duration (180ms) who received dual-chamber implantable cardioverter-defibrillator for primary prevention of sudden death. After having placed the right ventricular lead in the middle of the inter-ventricular septum, a significant narrowing of QRS duration was observed, thus obtaining "de facto" a cardiac resynchronization therapy (CRT). This type of cardiac pacing could be an alternative to conventional CRT with left ventricular pacing in patients with wide QRS due to RBBB. The long-term effects of this RV only pacing strategy with ICD in patients with heart failure yet remain to be determined. PMID:25464987

Crea, Pasquale; Andò, Giuseppe; Zagari, Domenico; Giordano, Antonio; Picciolo, Giuseppe; Oreto, Giuseppe

2015-01-01

67

Noninvasive fetal QRS detection using an echo state network and dynamic programming.  

PubMed

We address a classical fetal QRS detection problem from abdominal ECG recordings with a data-driven statistical machine learning approach. Our goal is to have a powerful, yet conceptually clean, solution. There are two novel key components at the heart of our approach: an echo state recurrent neural network that is trained to indicate fetal QRS complexes, and several increasingly sophisticated versions of statistics-based dynamic programming algorithms, which are derived from and rooted in probability theory. We also employ a standard technique for preprocessing and removing maternal ECG complexes from the signals, but do not take this as the main focus of this work. The proposed approach is quite generic and can be extended to other types of signals and annotations. Open-source code is provided. PMID:25069892

Lukoševi?ius, Mantas; Marozas, Vaidotas

2014-08-01

68

A Joint QRS Detection and Data Compression Scheme for Wearable Sensors.  

PubMed

This paper presents a novel electrocardiogram (ECG) processing technique for joint data compression and QRS detection in a wireless wearable sensor. The proposed algorithm is aimed at lowering the average complexity per task by sharing the computational load among multiple essential signal-processing tasks needed for wearable devices. The compression algorithm, which is based on an adaptive linear data prediction scheme, achieves a lossless bit compression ratio of 2.286x. The QRS detection algorithm achieves a sensitivity (Se) of 99.64% and positive prediction (+P) of 99.81% when tested with the MIT/BIH Arrhythmia database. Lower overall complexity and good performance renders the proposed technique suitable for wearable/ambulatory ECG devices. PMID:25073164

Deepu, C J; Lian, Y

2015-01-01

69

The case of the QRS-T angles versus QRST integral maps.  

PubMed

This contribution discusses the QRS-T angle as well as the QRST integral map. Both of these topics have been tested in their application in extracting the major features of depolarization and repolarization: their spatio-temporal behaviour, and how much of their global or local nature might be deduced from signals that can be observed clinically. Recently, it is in particular the QRS-T angle that has received considerable attention, a method that stems directly from vectorcardiography, a subdomain of electrocardiography. The QRST integral map is a display of a map on the body surface of the integrals over time of the ECG signals observed at sets of electrodes. The common biophysical background of both techniques is highlighted. In particular it is explained why, in healthy myocardium, both provide a similar view on the global timing of the depolarization and repolarization of all cardiac myocytes, more specifically, on the dispersion of their action potential durations. In the presence of ischemia, the view obtained is of the integral over time of the transmembrane potentials, which comprises a 'mixture' of their timing and magnitude. The analysis of results of a simulation study emphasizes the large discrepancies that may be observed between the QRS-T angle in the frontal plane and its 3D variant. It is shown that the required vector representation of the signals may be derived from the 12-lead ECG by using the transfer matrix proposed in 1990 by Kors and colleagues. PMID:24360344

van Oosterom, Adriaan

2014-01-01

70

Temporal and postural variation of 12-lead high-frequency QRS electrocardiographic signals in asymptomatic individuals  

Microsoft Academic Search

Because changes in the 12-lead high-frequency QRS electrocardiogram (HF QRS ECG) more sensitively identify myocardial ischemia than do changes in the ST segments of the conventional ECG, it is important that changes in HF QRS signals that are merely physiological be distinguishable from those that are potentially pathological. We therefore studied the temporal variation of HF QRS measures such as

Pamela K. Douglas; Niles J. Batdorf; Richard T. Evans; Alan H. Feiveson; Brian Arenare; Todd T. Schlegel

2006-01-01

71

Variation in canopy duration in the perennial biofuel crop Miscanthus reveals complex associations with yield  

PubMed Central

Energy crops can provide a sustainable source of power and fuels, and mitigate the negative effects of CO2 emissions associated with fossil fuel use. Miscanthus is a perennial C4 energy crop capable of producing large biomass yields whilst requiring low levels of input. Miscanthus is largely unimproved and therefore there could be significant opportunities to increase yield. Further increases in yield will improve the economics, energy balance, and carbon mitigation of the crop, as well as reducing land-take. One strategy to increase yield in Miscanthus is to maximize the light captured through an extension of canopy duration. In this study, canopy duration was compared among a diverse collection of 244 Miscanthus genotypes. Canopy duration was determined by calculating the number of days between canopy establishment and senescence. Yield was positively correlated with canopy duration. Earlier establishment and later senescence were also both separately correlated with higher yield. However, although genotypes with short canopy durations were low yielding, not all genotypes with long canopy durations were high yielding. Differences of yield between genotypes with long canopy durations were associated with variation in stem and leaf traits. Different methodologies to assess canopy duration traits were investigated, including visual assessment, image analysis, light interception, and different trait thresholds. The highest correlation coefficients were associated with later assessments of traits and the use of quantum sensors for canopy establishment. A model for trait optimization to enable yield improvement in Miscanthus and other bioenergy crops is discussed. PMID:23599277

Robson, Paul R.H.

2013-01-01

72

Variation in canopy duration in the perennial biofuel crop Miscanthus reveals complex associations with yield.  

PubMed

Energy crops can provide a sustainable source of power and fuels, and mitigate the negative effects of CO2 emissions associated with fossil fuel use. Miscanthus is a perennial C4 energy crop capable of producing large biomass yields whilst requiring low levels of input. Miscanthus is largely unimproved and therefore there could be significant opportunities to increase yield. Further increases in yield will improve the economics, energy balance, and carbon mitigation of the crop, as well as reducing land-take. One strategy to increase yield in Miscanthus is to maximize the light captured through an extension of canopy duration. In this study, canopy duration was compared among a diverse collection of 244 Miscanthus genotypes. Canopy duration was determined by calculating the number of days between canopy establishment and senescence. Yield was positively correlated with canopy duration. Earlier establishment and later senescence were also both separately correlated with higher yield. However, although genotypes with short canopy durations were low yielding, not all genotypes with long canopy durations were high yielding. Differences of yield between genotypes with long canopy durations were associated with variation in stem and leaf traits. Different methodologies to assess canopy duration traits were investigated, including visual assessment, image analysis, light interception, and different trait thresholds. The highest correlation coefficients were associated with later assessments of traits and the use of quantum sensors for canopy establishment. A model for trait optimization to enable yield improvement in Miscanthus and other bioenergy crops is discussed. PMID:23599277

Robson, Paul R H; Farrar, Kerrie; Gay, Alan P; Jensen, Elaine F; Clifton-Brown, John C; Donnison, Iain S

2013-05-01

73

Month-to-Month and Year-to-Year Reproducibility of High Frequency QRS ECG signals  

NASA Technical Reports Server (NTRS)

High frequency (HF) electrocardiography analyzing the entire QRS complex in the frequency range of 150 to 250 Hz may prove useful in the detection of coronary artery disease, yet the long-term stability of these waveforms has not been fully characterized. We therefore prospectively investigated the reproducibility of the root mean squared (RMS) voltage, kurtosis, and the presence versus absence of reduced amplitude zones (RAzs) in signal averaged 12-lead HF QRS recordings acquired in the supine position one month apart in 16 subjects and one year apart in 27 subjects. Reproducibility of RMS voltage and kurtosis was excellent over these time intervals in the limb leads, and acceptable in the precordial leads using both the V-lead and CR-lead derivations. The relative error of RMS voltage was 12% month-to-month and 16% year-to-year in the serial recordings when averaged over all 12 leads. RAzs were also reproducible at a rate of up to 87% and 8 1 %, respectively, for the month-to-month and year-to-year recordings. We conclude that 12-lead HF QRS electrocardiograms are sufficiently reproducible for clinical use.

Batdorf, Niles; Feiveson, Alan H.; Schlegel, Todd T.

2006-01-01

74

Month-to-month and year-to-year reproducibility of high frequency QRS ECG signals  

NASA Technical Reports Server (NTRS)

High frequency electrocardiography analyzing the entire QRS complex in the frequency range of 150 to 250 Hz may prove useful in the detection of coronary artery disease, yet the long-term stability of these waveforms has not been fully characterized. Therefore, we prospectively investigated the reproducibility of the root mean squared voltage, kurtosis, and the presence versus absence of reduced amplitude zones in signal averaged 12-lead high frequency QRS recordings acquired in the supine position one month apart in 16 subjects and one year apart in 27 subjects. Reproducibility of root mean squared voltage and kurtosis was excellent over these time intervals in the limb leads, and acceptable in the precordial leads using both the V-lead and CR-lead derivations. The relative error of root mean squared voltage was 12% month-to-month and 16% year-to-year in the serial recordings when averaged over all 12 leads. Reduced amplitude zones were also reproducible up to a rate of 87% and 81%, respectively, for the month-to-month and year-to-year recordings. We conclude that 12-lead high frequency QRS electrocardiograms are sufficiently reproducible for clinical use.

Batdorf, Niles J.; Feiveson, Alan H.; Schlegel, Todd T.

2004-01-01

75

Month-to-month and year-to-year reproducibility of high frequency QRS ECG signals.  

PubMed

High frequency electrocardiography analyzing the entire QRS complex in the frequency range of 150 to 250 Hz may prove useful in the detection of coronary artery disease, yet the long-term stability of these waveforms has not been fully characterized. Therefore, we prospectively investigated the reproducibility of the root mean squared voltage, kurtosis, and the presence versus absence of reduced amplitude zones in signal averaged 12-lead high frequency QRS recordings acquired in the supine position one month apart in 16 subjects and one year apart in 27 subjects. Reproducibility of root mean squared voltage and kurtosis was excellent over these time intervals in the limb leads, and acceptable in the precordial leads using both the V-lead and CR-lead derivations. The relative error of root mean squared voltage was 12% month-to-month and 16% year-to-year in the serial recordings when averaged over all 12 leads. Reduced amplitude zones were also reproducible up to a rate of 87% and 81%, respectively, for the month-to-month and year-to-year recordings. We conclude that 12-lead high frequency QRS electrocardiograms are sufficiently reproducible for clinical use. PMID:15484157

Batdorf, Niles J; Feiveson, Alan H; Schlegel, Todd T

2004-10-01

76

Low power adder based digital filter for QRS detector.  

PubMed

Most of the Biomedical applications use dedicated processors for the implementation of complex signal processing. Among them, sensor network is also a type, which has the constraint of low power consumption. Since the processing elements are the most copiously used operations in the signal processors, the power consumption of this has the major impact on the system level application. In this paper, we introduce low power concept of transistor stacking to reduce leakage power; and new architectures based on stacking to implement the full adder and its significance at the digital filter level for QRS detector are implemented. The proposed concept has lesser leakage power at the adder as well as filter level with trade-off in other quality metrics of the design. This enabled the design to be dealt with as the low-power corner and can be made adaptable to any level of hierarchical abstractions as per the requirement of the application. The proposed architectures are designed, modeled at RTL level using the Verilog-HDL, and synthesized in Synopsys Design Compiler by mapping the design to 65 nm technology library standard cells. PMID:24895649

Murali, L; Chitra, D; Manigandan, T

2014-01-01

77

Low Power Adder Based Digital Filter for QRS Detector  

PubMed Central

Most of the Biomedical applications use dedicated processors for the implementation of complex signal processing. Among them, sensor network is also a type, which has the constraint of low power consumption. Since the processing elements are the most copiously used operations in the signal processors, the power consumption of this has the major impact on the system level application. In this paper, we introduce low power concept of transistor stacking to reduce leakage power; and new architectures based on stacking to implement the full adder and its significance at the digital filter level for QRS detector are implemented. The proposed concept has lesser leakage power at the adder as well as filter level with trade-off in other quality metrics of the design. This enabled the design to be dealt with as the low-power corner and can be made adaptable to any level of hierarchical abstractions as per the requirement of the application. The proposed architectures are designed, modeled at RTL level using the Verilog-HDL, and synthesized in Synopsys Design Compiler by mapping the design to 65?nm technology library standard cells. PMID:24895649

Murali, L.; Chitra, D.; Manigandan, T.

2014-01-01

78

Prosodic Planning: Effects of Phrasal Length and Complexity on Pause Duration  

PubMed Central

Research on pause duration has mainly focused on the impact of syntactic structure on the duration of pauses within an utterance and on the impact of syntax, discourse, and prosodic structure on the likelihood of pause occurrence. Relatively little is known about what factors play a role in determining the duration of pauses between utterances or phrases. Two experiments examining the effect of prosodic structure and phrase length on pause duration are reported. Subjects read sentences varying along the following parameters: a) the length in syllables of the intonational phrase preceding and following the pause, and b) the prosodic structure of the intonational phrase preceding and following the pause, specifically whether or not the intonational phrase branches into smaller phrases. In order to minimize variability due to speech rate and individual differences, speakers read sentences synchronously in dyads. The results showed a significant post-boundary effect of prosodic branching and significant pre- and post-boundary phrase length effects. The results are discussed in terms of production units. PMID:18379639

Krivokapi, Jelena

2007-01-01

79

Aviation System Analysis Capability (ASAC) Quick Response System (QRS) Test Report  

NASA Technical Reports Server (NTRS)

This document is the Aviation System Analysis Capability (ASAC) Quick Response System (QRS) Test Report. The purpose of this document is to present the results of the QRS unit and system tests in support of the ASAC QRS development effort. This document contains an overview of the project background and scope, defines the QRS system and presents the additions made to the QRS this year, explains the assumptions, constraints, and approach used to conduct QRS Unit and System Testing, and presents the schedule used to perform QRS Testing. The document also presents an overview of the Logistics Management Institute (LMI) Test Facility and testing environment and summarizes the QRS Unit and System Test effort and results.

Roberts, Eileen; Villani, James A.; Ritter, Paul

1997-01-01

80

QRS pattern and improvement in right and left ventricular function after cardiac resynchronization therapy: a radionuclide study  

PubMed Central

Background Predicting response to cardiac resynchronization therapy (CRT) remains a challenge. We evaluated the role of baseline QRS pattern to predict response in terms of improvement in biventricular ejection fraction (EF). Methods Consecutive patients (pts) undergoing CRT implantation underwent radionuclide angiography at baseline and at mid-term follow-up. The relationship between baseline QRS pattern and mechanical dyssynchrony using phase analysis was evaluated. Changes in left and right ventricular EF (LVEF and RVEF) were analyzed with regard to baseline QRS pattern. Results We enrolled 56 pts, 32 with left bundle branch block (LBBB), 4 with right bundle branch block (RBBB) and 20 with non-specific intraventricular conduction disturbance (IVCD). A total of 48 pts completed follow-up. LBBB pts had significantly greater improvement in LVEF compared to RBBB or non-specific IVCD pts (+9.6 ± 10.9% vs. +2.6 ± 7.6%, p = 0.003). Response (defined as ? 5% increase in LVEF) was observed in 68% of LBBB vs. 24% of non-specific IVCD pts (p = 0.006). None of the RBBB pts were responders. RVEF was significantly improved in LBBB (+5.0 ± 9.0%, p = 0.007), but not in non-specific IVCD and RBBB pts (+0.4 ± 5.8%, p = 0.76). At multivariate analysis, LBBB was the only predictor of LVEF response (OR, 7.45; 95% CI 1.80-30.94; p = 0.006), but not QRS duration or extent of mechanical dyssynchrony. Conclusions Presence of a LBBB is a marker of a positive response to CRT in terms of biventricular improvement. Pts with non-LBBB pattern show significantly less benefit from CRT than those with LBBB. PMID:22494365

2012-01-01

81

Exercise-induced QRS amplitude changes in patients with isolated myocardial bridging: a marker of myocardial ischemia.  

PubMed

Myocardial bridging (MB) of coronary arteries has been considered as an incidental angio-graphic finding; however, several reports suggest its association with angina pectoris, myocardial ischemia, and even infarction. In this study the authors aimed to assess exercise-induced QRS changes in patients with isolated MB and to compare those with coronary artery disease (CAD) and healthy subjects. The study population consisted of 17 patients with angiographically proven MB (group 1), 16 patients with left anterior descending (LAD) artery stenosis (group 2), and 14 healthy subjects (group 3). Each subject underwent treadmill exercise testing according to Bruce protocol. In each subject amplitude of the Q, R, and S waves in leads aVF and V(5) was measured manually before and immediately after exercise. The Athens QRS score was calculated by subtracting the Q-, R-, and S-wave differences in leads aVF and V(5). Baseline characteristics of each group were similar. There was no difference among the groups with respect to exercise testing parameters (peak heart rate, blood pressure, test duration, etc). In group 1, ST-segment depression ratio was found to be higher than that of group 3 but lower than that of group 2. In group 1, exercise QRS score was found to be lower than that of group 3 while it was higher than that of group 2 (2.9 +/- 2.3 vs 6.5 +/- 3.2 p = 0.001 and 2.9 +/- 2.3 vs 2.6 +/- 2.4 p = 0.001, respectively). In patients with MB exercise, QRS score was significantly lower than in those with normal coronary flow while it was higher in those with CAD. This may result from exercise-induced ischemia at the area perfused by the bridged artery. PMID:15889193

Turkmen, Muhsin; Barutcu, Irfan; Esen, Ali Metin; Karakaya, Osman; Esen, Ozlem; Basaran, Yelda

2005-01-01

82

Empirical mode decomposition based ECG enhancement and QRS detection.  

PubMed

In this paper an Empirical Mode Decomposition (EMD) based ECG signal enhancement and QRS detection algorithm is proposed. Being a non-invasive measurement, ECG is prone to various high and low frequency noises causing baseline wander and power line interference, which act as a source of error in QRS and other feature extraction. EMD is a fully adaptive signal decomposition technique that generates Intrinsic Mode Functions (IMF) as decomposition output. Here, first baseline wander is corrected by selective reconstruction based slope minimization technique from IMFs and then high frequency noise is removed by eliminating a noisy set of lower order IMFs with a statistical peak correction as high frequency noise elimination is accompanied by peak deformation of sharp characteristic waves. Then a set of IMFs are selected that represents QRS region and a nonlinear transformation is done for QRS enhancement. This improves detection accuracy, which is represented in the result section. Thus in this method a single fold processing of each signal is required unlike other conventional techniques. PMID:22119222

Pal, Saurabh; Mitra, Madhuchhanda

2012-01-01

83

Real Time QRS Detection Based on M-ary Likelihood Ratio Test on the DFT Coefficients  

PubMed Central

This paper shows an adaptive statistical test for QRS detection of electrocardiography (ECG) signals. The method is based on a M-ary generalized likelihood ratio test (LRT) defined over a multiple observation window in the Fourier domain. The motivations for proposing another detection algorithm based on maximum a posteriori (MAP) estimation are found in the high complexity of the signal model proposed in previous approaches which i) makes them computationally unfeasible or not intended for real time applications such as intensive care monitoring and (ii) in which the parameter selection conditions the overall performance. In this sense, we propose an alternative model based on the independent Gaussian properties of the Discrete Fourier Transform (DFT) coefficients, which allows to define a simplified MAP probability function. In addition, the proposed approach defines an adaptive MAP statistical test in which a global hypothesis is defined on particular hypotheses of the multiple observation window. In this sense, the observation interval is modeled as a discontinuous transmission discrete-time stochastic process avoiding the inclusion of parameters that constraint the morphology of the QRS complexes. PMID:25356628

Górriz, Juan Manuel; Ramírez, Javier; Olivares, Alberto; Padilla, Pablo; Puntonet, Carlos G.; Cantón, Manuel; Laguna, Pablo

2014-01-01

84

QRS detection by lifting scheme constructing multi-resolution morphological decomposition.  

PubMed

QRS complex detecting algorithm is core of ECG auto-diagnosis method and deeply influences cardiac cycle division for signal compression. However, ECG signals collected by noninvasive surface electrodes areusually mixed with several kinds of interference, and its waveform variation is the main reason for the hard realization of ECG processing. This paper proposes a QRS complex detecting algorithm based on multi-resolution mathematical morphological decomposition. This algorithm possesses superiorities in R peak detection of both mathematical morphological method and multi-resolution decomposition. Moreover, a lifting constructing method with Maximizationupdating operator is adopted to further improve the algorithm performance. And an efficient R peak search-back algorithm is employed to reduce the false positives (FP) and false negatives (FN). The proposed algorithm provides a good performance applying to MIT-BIH Arrhythmia Database, and achieves over 99% detection rate, sensitivity and positive predictivity, respectively, and calculation burden is low. Therefore, the proposed method is appropriate for portable medical devices in Telemedicine system. PMID:25569905

Pu Zhang; Ma, Heather T; Qinyu Zhang

2014-08-01

85

Louisiana Quality Start Child Care Rating System: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Louisiana's Quality Start Child Care Rating System prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs;…

Child Trends, 2010

2010-01-01

86

Tennessee Star-Quality Child Care Program: QRS Profile. The Child Care Quality Rating System (QRS) Assessment  

ERIC Educational Resources Information Center

This paper presents a profile of Tennessee's Star-Quality Child Care Program prepared as part of the Child Care Quality Rating System (QRS) Assessment Study. The profile consists of several sections and their corresponding descriptions including: (1) Program Information; (2) Rating Details; (3) Quality Indicators for Center-Based Programs; (4)…

Child Trends, 2010

2010-01-01

87

High frequency QRS ECG predicts ischemic defects during myocardial perfusion imaging  

NASA Technical Reports Server (NTRS)

Changes in high frequency QRS components of the electrocardiogram (HF QRS ECG) (150-250 Hz) are more sensitive than changes in conventional ST segments for detecting myocardial ischemia. We investigated the accuracy of 12-lead HF QRS ECG in detecting ischemia during adenosine tetrofosmin myocardial perfusion imaging (MPI). 12-lead HF QRS ECG recordings were obtained from 45 patients before and during adenosine technetium-99 tetrofosmin MPI tests. Before the adenosine infusions, recordings of HF QRS were analyzed according to a morphological score that incorporated the number, type and location of reduced amplitude zones (RAZs) present in the 12 leads. During the adenosine infusions, recordings of HF QRS were analyzed according to the maximum percentage changes (in both the positive and negative directions) that occurred in root mean square (RMS) voltage amplitudes within the 12 leads. The best set of prospective HF QRS criteria had a sensitivity of 94% and a specificity of 83% for correctly identifying the MPI result. The sensitivity of simultaneous ST segment changes (18%) was significantly lower than that of any individual HF QRS criterion (P less than 0.00l). Analysis of 12-lead HF QRS ECG is highly sensitive and specific for detecting ischemic perfusion defects during adenosine MPI stress tests and significantly more sensitive than analysis of conventional ST segments.

2004-01-01

88

High frequency QRS ECG predicts ischemic defects during myocardial perfusion imaging  

NASA Technical Reports Server (NTRS)

Background: Changes in high frequency QRS components of the electrocardiogram (HF QRS ECG) (150-250 Hz) are more sensitive than changes in conventional ST segments for detecting myocardial ischemia. We investigated the accuracy of 12-lead HF QRS ECG in detecting ischemia during adenosine tetrofosmin myocardial perfusion imaging (MPI). Methods and Results: 12-lead HF QRS ECG recordings were obtained from 45 patients before and during adenosine technetium-99 tetrofosmin MPI tests. Before the adenosine infusions, recordings of HF QRS were analyzed according to a morphological score that incorporated the number, type and location of reduced amplitude zones (RAZs) present in the 12 leads. During the adenosine infusions, recordings of HF QRS were analyzed according to the maximum percentage changes (in both the positive and negative directions) that occurred in root mean square (RMS) voltage amplitudes within the 12 leads. The best set of prospective HF QRS criteria had a sensitivity of 94% and a specificity of 83% for correctly identifying the MPI result. The sensitivity of simultaneous ST segment changes (18%) was significantly lower than that of any individual HF QRS criterion (P<0.001). Conclusions: Analysis of 12-lead HF QRS ECG is highly sensitive and specific for detecting ischemic perfusion defects during adenosine MPI stress tests and significantly more sensitive than analysis of conventional ST segments.

Rahman, Atiar

2006-01-01

89

Real-Time, High-Frequency QRS Electrocardiograph  

NASA Technical Reports Server (NTRS)

An electronic system that performs real-time analysis of the low-amplitude, high-frequency, ordinarily invisible components of the QRS portion of an electrocardiographic signal in real time has been developed. Whereas the signals readily visible on a conventional electrocardiogram (ECG) have amplitudes of the order of a millivolt and are characterized by frequencies <100 Hz, the ordinarily invisible components have amplitudes in the microvolt range and are characterized by frequencies from about 150 to about 250 Hz. Deviations of these high-frequency components from a normal pattern can be indicative of myocardial ischemia or myocardial infarction

Schlegel, Todd T.; DePalma, Jude L.; Moradi, Saeed

2003-01-01

90

MS no 04/102 Evaluation of real-time QRS detection  

E-print Network

ECG records. For each morphology context, the set of extracted beats, ranging from 30 to 23000 the best QRS detector according to the current context. Keywords: ECG analysis, QRS detection, algorithms evaluation, best algorithm selection, real time signal monitoring inria-00001102,version1-6Feb2006 #12;MS

Boyer, Edmond

91

Correlation between fragmented QRS and the short-term prognosis of patients with acute myocardial infarction*  

PubMed Central

This study is aimed to investigate the clinical significance and the short-term prognostic value of fragmented QRS (fQRS) for patients with acute myocardial infarction (AMI). Three hundred patients with AMI were tested with retrospective analysis on the patients’ clinical information, hospitalized treatment, fQRS onset time, location of lesions, and other relevant data, in order to assess the relationship between the presence of fQRS and its prognosis. The rates of malignant cardiac arrhythmia, left ventricular systolic dysfunction (LVSD), and mortality in the positive fQRS group were 13.6%, 29.2%, and 23.7%, respectively, with all showing a p value <0.05. For the ST segment elevation myocardial infarction (STEMI) subgroup, all the rates showed significant differences with a p value <0.01, while for the non-STEMI (NSTEMI) subgroup showed no significant differences. In patients with a positive fQRS, there were no differences in malignant cardiac arrhythmia between patients with and without percutaneous coronary intervention (PCI) (p>0.05). As for the LVSD and mortality, the p values between patients with and without PCI were 0.031 and 0.000, respectively, suggesting statistical significance. The results imply that AMI patients with positive fQRS especially for the patients with STEMI had higher rates of malignant cardiac arrhythmia, LVSD, and mortality than the non-fQRS group. Patients of AMI with positive fQRS, who underwent early revascularization, could lower the incidence of the cardiovascular event. In addition, the presence of fQRS could be used as an indication of early intervention treatment for patients. PMID:24390746

Sheng, Qin-hui; Hsu, Chih-Chi; Li, Jian-ping; Hong, Tao; Huo, Yong

2014-01-01

92

Electrocardiographic assessment of left ventricular hypertrophy with time-voltage QRS and QRST-wave areas.  

PubMed

The sum of time-voltage QRS areas in the 12-lead electrocardiogram (ECG) has outperformed other 12-lead ECG indices for detection of left ventricular hypertrophy (LVH). We assessed indices of time-voltage QRS and T-wave (QRST) areas from body surface potential mapping (BSPM) for detection of and quantitation of the degree of LVH. We studied 42 patients with echocardiographic LVH (LVH group) and 11 healthy controls (controls). QRST area sums were calculated from 123-lead BSPM and from the 12-lead ECG for comparison. Leadwise discriminant indices and correlation coefficients were used to identify optimal recording locations for QRST area-based LVH assessment. BSPM QRS area sum was greater in the LVH group than in controls (3752 +/- 1259 vs 2278 +/- 627 microV s, respectively; P<0.001) and at 91% specificity showed 74% sensitivity for LVH detection. The 12-lead QRS area sum performed similarly. Taking T-wave areas into account did not improve the results. QRS area sum from two most informative leads (located in the upper and lower right precordium) also separated the LVH group from controls (61.1 +/- 23.5 vs 27.8 +/- 6.5 microV s, respectively; P<0.00001). This 2-lead QRS area sum showed 90% sensitivity with 100% specificity for LVH detection and maintained high correlation to indexed left ventricular mass (r=0.732; P<0.001). In conclusion, the BSPM QRS area sum compared to 12-lead QRS area sum does not substantially improve LVH assessment. The 2-lead QRS area sum may improve ECG QRS area-based LVH assessment. PMID:14688808

Oikarinen, L; Karvonen, M; Viitasalo, M; Takala, P; Kaartinen, M; Rossinen, J; Tierala, I; Hänninen, H; Katila, T; Nieminen, M S; Toivonen, L

2004-01-01

93

Circulating Serum Markers and QRS Scar Score in Chagas Cardiomyopathy.  

PubMed

Approximately 8 million people have Trypanosoma cruzi infection, and nearly 30% will manifest Chagas cardiomyopathy (CC). Identification of reliable early indicators of CC risk would enable prioritization of treatment to those with the highest probability of future disease. Serum markers and electrocardiogram (EKG) changes were measured in 68 T. cruzi-infected individuals in various stages of cardiac disease and 17 individuals without T. cruzi infection or cardiac disease. T. cruzi-infected individuals were assigned to stage A (normal EKG/chest x-ray [CXR]), B (abnormal EKG/normal CXR), or C (abnormal EKG/cardiac structural changes). Ten serum markers were measured using enzyme-linked immunosorbent assay (ELISA)/Luminex, and QRS scores were calculated. Higher concentrations of transforming growth factor-?1 (TGF?1), and TGF?2 were associated with stage B compared with stage A. Matrix Metalloproteinase 2 (MMP2), Tissue Inhibitors of MMP 1, QRS score, and Brain Natriuretic Protein rose progressively with increasing CC severity. Elevated levels of several markers of cardiac damage and inflammation are seen in early CC and warrant additional evaluation in longitudinal studies. PMID:25385865

Clark, Eva H; Marks, Morgan A; Gilman, Robert H; Fernandez, Antonio B; Crawford, Thomas C; Samuels, Aaron M; Hidron, Alicia I; Galdos-Cardenas, Gerson; Menacho-Mendez, Gilberto Silvio; Bozo-Gutierrez, Ricardo W; Martin, Diana L; Bern, Caryn

2015-01-01

94

Temporal and postural variation of 12-lead high-frequency QRS electrocardiographic signals in asymptomatic individuals.  

PubMed

Because changes in the 12-lead high-frequency QRS electrocardiogram (HF QRS ECG) more sensitively identify myocardial ischemia than do changes in the ST segments of the conventional ECG, it is important that changes in HF QRS signals that are merely physiological be distinguishable from those that are potentially pathological. We therefore studied the temporal variation of HF QRS measures such as root mean square (RMS) voltage and the presence vs absence of reduced amplitude zones (RAZs) in 107 asymptomatic individuals in the supine position during a brief period of ECG monitoring. In addition, to ascertain the effects of posture on the 12-lead HF QRS ECG, we collected additional seated data from 25 of these individuals and estimated the fifth and 95th percentile of the percent relative change between the supine and seated measurements. In all cases, variation of HF QRS parameters decreased as the number of beats in the signal average increased. For example, in the supine position, the 95th percentile of the percent relative change between consecutive within-lead measurements of RMS voltage for a 50-beat signal average was 12.3% but decreased to 11.7%, 11.2%, and 10.7% for 75, 100, and 150 beat signal averages, respectively (P < .01). After transition from the supine to the seated upright position, changes in some measures of HF QRS were statistically significant, with RMS voltage decreasing significantly in lead V3 and with the number of RAZs lost in the 12-lead HF QRS ECG significantly exceeding the number of RAZs gained. We conclude that most measures of HF QRS ECG are sufficiently stable for routine continuous monitoring. PMID:16777512

Douglas, Pamela K; Batdorf, Niles J; Evans, Richard T; Feiveson, Alan H; Arenare, Brian; Schlegel, Todd T

2006-07-01

95

Development of a Multi-Channel, High Frequency QRS Electrocardiograph  

NASA Technical Reports Server (NTRS)

With the advent of the ISS era and the potential requirement for increased cardiovascular monitoring of crewmembers during extended EVAs, NASA flight surgeons would stand to benefit from an evolving technology that allows for a more rapid diagnosis of myocardial ischemia compared to standard electrocardiography. Similarly, during the astronaut selection process, NASA flight surgeons and other physicians would also stand to benefit from a completely noninvasive technology that, either at rest or during maximal exercise tests, is more sensitive than standard ECG in identifying the presence of ischemia. Perhaps most importantly, practicing cardiologists and emergency medicine physicians could greatly benefit from such a device as it could augment (or even replace) standard electrocardiography in settings where the rapid diagnosis of myocardial ischemia (or the lack thereof) is required for proper clinical decision-making. A multi-channel, high-frequency QRS electrocardiograph is currently under development in the Life Sciences Research Laboratories at JSC. Specifically the project consisted of writing software code, some of which contained specially-designed digital filters, which will be incorporated into an existing commercial software program that is already designed to collect, plot and analyze conventional 12-lead ECG signals on a desktop, portable or palm PC. The software will derive the high-frequency QRS signals, which will be analyzed (in numerous ways) and plotted alongside of the conventional ECG signals, giving the PC-viewing clinician advanced diagnostic information that has never been available previously in all 12 ECG leads simultaneously. After the hardware and software for the advanced digital ECG monitor have been fully integrated, plans are to use the monitor to begin clinical studies both on healthy subjects and on patients with known coronary artery disease in both the outpatient and hospital settings. The ultimate goal is to get the technology out into the clinical world, where it has the potential to save lives.

DePalma, Jude L.

2003-01-01

96

Ventricular Arrhythmia is predicted by Sum Absolute QRST Integral, but not by QRS width  

PubMed Central

Background There is a controversy regarding the association between QRS width and ventricular arrhythmias (VA). We hypothesized that predictive value of the QRS width could be improved if QRS width were considered in the context of the sum magnitude of the absolute QRST integral in three orthogonal leads (SAI QRST). We explored correlations between QRS width, SAI QRST, and VA in primary prevention ICD patients with structural heart disease. Methods Baseline orthogonal ECGs were recorded at rest in 355 patients with implanted primary prevention ICDs (mean age 59.5±12.4; 279 male [79%]). Patients were followed prospectively at least 6 months; appropriate ICD therapies due to sustained VA served as endpoints. The sum magnitude of the absolute QRST integral in three orthogonal leads (SAI QRST) was calculated. Results During a mean follow-up of 18 months, 48 patients had sustained VA and received appropriate ICD therapies. There was no difference in baseline QRS width between patients with and those without arrhythmia (114.9±32.8 vs. 108.9±24.7 ms, p=0.230). SAI QRST was significantly lower in patients with VA at follow-up than in patients without VA (102.6±27.6 vs. 112.0±31.9 mV*ms, p=0.034). Patients with SAI QRST ?145 mV*ms had a3-fold higher risk of VT/VF (HR 3.25; 95% CI: 1.59–6.75, p=0.001). In the univariate analysis QRS width did not predict VT/VF. In the bivariate Cox regression model every 1 ms of incremental QRS widening with a simultaneous 1 mV*ms SAI QRST decrease raised the risk of VT/VF by 2% (HR 1.02; 95% CI 1.01–1.03, p=0.005). Conclusion QRS widening is associated with ventricular tachyarrhythmia only if accompanied by low SAI QRST. PMID:20832820

Tereshchenko, Larisa G.; Cheng, Alan; Fetics, Barry J.; Marine, Joseph E.; Spragg, David D.; Sinha, Sunil; Calkins, Hugh; Tomaselli, Gordon F.; Berger, Ronald D.

2010-01-01

97

A 0.83- ?W QRS detection processor using quadratic spline wavelet transform for wireless ECG acquisition in 0.35- ?m CMOS.  

PubMed

Healthcare electronics count on the effectiveness of the on-patient signal preprocessing unit to moderate the wireless data transfer for better power efficiency. In order to reduce the system power in long-time ECG acquisition, this work describes an on-patient QRS detection processor for arrhythmia monitoring. It extracts the concerned ECG part, i.e., the RR-interval between the QRS complex for evaluating the heart rate variability. The processor is structured by a scale-3 quadratic spline wavelet transform followed by a maxima modulus recognition stage. The former is implemented via a symmetric FIR filter, whereas the latter includes a number of feature extraction steps: zero-crossing detection, peak (zero-derivative) detection, threshold adjustment and two finite state machines for executing the decision rules. Fabricated in 0.35-?m CMOS the 300-Hz processor draws only 0.83 ?W, which is favorably comparable with the prior arts. In the system tests, the input data is placed via an on-chip 10-bit SAR analog-to-digital converter, while the output data is emitted via an off-the-shelf wireless transmitter (TI CC2500) that is configurable by the processor for different data transmission modes: 1) QRS detection result, 2) raw ECG data or 3) both. Validated with all recordings from the MIT-BIH arrhythmia database, 99.31% sensitivity and 99.70% predictivity are achieved. Mode 1 with solely the result of QRS detection exhibits 6× reduction of system power over modes 2 and 3. PMID:23853259

Ieong, Chio-In; Mak, Pui-In; Lam, Chi-Pang; Dong, Cheng; Vai, Mang-I; Mak, Peng-Un; Pun, Sio-Hang; Wan, Feng; Martins, Rui P

2012-12-01

98

Etanercept Induces Low QRS Voltage and Autonomic Dysfunction in Mice with Experimental Chagas Disease  

PubMed Central

Background Chagas disease is a tropical parasitic disease caused by the flagellate protozoan Trypanosoma cruzi. Chagasic cardiomyopathy is characterized by disorders of autonomic regulation and action potential conduction in the acute and chronic phases of infection. Although tumor necrosis factor alpha (TNF-?) has been linked to cardiomyopathy in experimental models and in patients with Chagas disease, other reports suggest that TNF-? may exert anti-parasitic actions during the acute phase of infection. Objectives This study aimed to determine the effects of a soluble TNF-? blocker, etanercept, on electrocardiographic parameters in the acute phase of experimental infection with Trypanosoma cruzi. Methods Electrocardiograms were obtained from untreated infected mice and infected mice who were treated with etanercept 7 days after infection. ECG wave and heart rate variability parameters were determined using Chart for Windows. Results Etanercept treatment resulted in a low QRS voltage and decreased heart rate variability compared with no treatment. However, the treated mice exhibited a delay in the fall of the survival curve during the acute phase. Conclusion The results of this study suggest that although etanercept treatment promotes survival in mice infected with a virulent T. cruzi strain, TNF-? blockade generates a low voltage complex and autonomic dysfunction during the acute phase of infection. These findings indicate that mortality during the acute phase can be attributed to a systemic inflammatory response rather than cardiac dysfunction. PMID:23877744

Rodríguez-Angulo, Héctor; García, Oscar; Castillo, Endher; Cardenas, Edward; Marques, Juan; Mijares, Alfredo

2013-01-01

99

Mechanical Dyssynchrony Precedes QRS Widening in ATP?Sensitive K+ Channel–Deficient Dilated Cardiomyopathy  

PubMed Central

Background Contractile discordance exacerbates cardiac dysfunction, aggravating heart failure outcome. Dissecting the genesis of mechanical dyssynchrony would enable an early diagnosis before advanced disease. Methods and Results High?resolution speckle?tracking echocardiography was applied in a knockout murine surrogate of adult?onset human cardiomyopathy caused by mutations in cardioprotective ATP?sensitive K+ (KATP) channels. Preceding the established criteria of cardiac dyssynchrony, multiparametric speckle?based strain resolved nascent erosion of dysfunctional regions within cardiomyopathic ventricles of the KATP channel–null mutant exposed to hemodynamic stress. Not observed in wild?type counterparts, intraventricular disparity in wall motion, validated by the degree, direction, and delay of myocardial speckle patterns, unmasked the disease substrate from asymptomatic to overt heart failure. Mechanical dyssynchrony preceded widening of the QRS complex and exercise intolerance and progressed into global myocardial discoordination and decompensated cardiac pump function, precipitating a low output syndrome. Conclusions The present study, with the use of high?resolution imaging, prospectively resolved the origin and extent of intraventricular motion disparity in a KATP channel–knockout model of dilated cardiomyopathy. Mechanical dyssynchrony established as an early marker of cardiomyopathic disease offers novel insight into the pathodynamics of dyssynchronous heart failure. PMID:24308936

Yamada, Satsuki; Arrell, D. Kent; Kane, Garvan C.; Nelson, Timothy J.; Perez?Terzic, Carmen M.; Behfar, Atta; Purushothaman, Saranya; Prinzen, Frits W.; Auricchio, Angelo; Terzic, Andre

2013-01-01

100

Interglacial Durations  

NASA Astrophysics Data System (ADS)

In the context of future global warming induced by human activities, it is essential to assess the role of natural climatic variations. Precise knowledge of the duration of past interglacial periods is fundamental to the understanding of the potential future evolution of the Holocene. Past ice age cycles provide a natural laboratory for exploring the progression and duration of interglacial climate. Palaeorecords from ice, land and oceans extend over the last 800 ka, revealing eight glacial-interglacial cycles, with a range of insolation and greenhouse gas influences. The interglacials display a correspondingly large variety of intensity and duration, thus providing an opportunity for major insights into the mechanisms involved in the behaviour of interglacial climates. A comparison of the duration of these interglacials, however, is often difficult, as the definition of an interglacial depends on the archive that is considered. Therefore, to compare interglacial length and climate conditions from different archives, a consistent definition of interglacial conditions is required, ideally one that is not bound to the method nor to the archive under consideration. Here we present a method to identify interglacials and to calculate their length by mean of a simple statistical approach. We based our method on ~ 400 ka windows of time to determine mean climatic conditions while allowing for the possibility of long term evolution of the climatic baseline. For our study of interglacials of the past 800 ka, we used two windows that largely align with the pre- (800-430 ka ago) and post- (430-0 ka ago) mid-Brunhes event (MBE), although the resulting conclusions are not sensitive to this particular division. We applied this method to the last 800 ka of a few palaeoclimate records: the deuterium ice core (EDC) record as a climatic proxy, the benthic ?18O stack (LR04) as a proxy for sea level/ice volume, ice core (Vostok, EDC) atmospheric CO2 and additional records. Although each climatic parameter has its own interglacial duration in this approach, important overall patterns emerge for individual interglacials. Interglacial conditions during the last interglacial, marine isotope stage (MIS) 5, as well as most pre-MBE interglacials persisted somewhat longer than the elapsed duration of the Holocene, while MIS 7 was shorter, and MIS 9 and MIS 19 were similar in duration. The longest interglacial durations overall characterized MIS 11, a frequent candidate as a potential Holocene and near future analogue because of similar orbital configurations (similarity shared also with MIS 19). Our study also reveals that interglacial high CO2 levels on the whole are within the duration range of the other paleoclimatic proxies and similar in length with the deuterium EDC record. This suggests that CO2 essentially plays a role of feedback when contributing to interglacial's duration. This exercise highlights the stability and variability in duration of the different interglacials as recorded in various proxy records under natural climate conditions. It may help identify past interglacial periods with conditions similar to those observed in the Holocene thus far, thereby allowing improved understanding of the human impact on climate.

Mangili, Clara; McManus, Jerry F.; Raynaud, Dominique

2014-05-01

101

Pulse Generators with Nanosecond Leading Edge Duration Based on TPI-Type Pseudospark Switches for FEL Complex  

Microsoft Academic Search

Summary form only given. For the FEL (Free Electron Laser) complex in Duke University five pulse generators (kickers) were developed and built. As fast switches TPI-type thyratrons (pseudospark switches) are used. In contrast with other pseudospark switches TPI-thyratrons are capable of operating in circuitry with a grounded cathode which allows obtaining service life time up to 20 000 hours. The

O. V. Anchugov; Yu. G. Matveev; D. A. Shvedov; V. D. Bochkov; D. V. Bochkov; V. M. Dyagilev; V. G. Ushich; V. G. Popov; S. F. Mikhailov

2007-01-01

102

Usefulness of QRS axis change to predict mortality in patients with left bundle branch block.  

PubMed

QRS duration correlates with poor prognosis in patients with left bundle branch block (LBBB), but the importance of left-axis deviation (LAD) is not well established. To determine if LAD confers a mortality risk in patients with LBBB, a single-center, retrospective, population-based cohort study was conducted. Included were all patients at 1 hospital with LBBB on electrocardiography from 1995 to 2005 over a 17-year follow-up period (n = 2,794, median follow-up duration 20 months, interquartile range 6 to 64). Half of all patients with LBBB had LAD. The all-cause mortality rate in the entire cohort was 15%. LAD was not associated with mortality, either as a single outcome (odds ratio [OR] 1.1, 95% confidence interval [CI] 0.88 to 1.3, p = 0.50) or in time-to-event analysis (p = 0.40). Significant risk factors for mortality included high creatinine (OR 1.2, 95% CI 1.1 to 1.3), low hemoglobin (OR 1.2, 95% CI 1.1 to 1.3), history of atrial fibrillation (OR 1.6, 95% CI 1.3 to 2.1), electrocardiographic evidence of previous infarct (OR 1.5, 95% CI 1.2 to 1.9), and history of ventricular tachycardia (OR 1.4, 95% CI 1.0 to 1.9). On bivariate analysis, LAD was associated with atrial fibrillation, ventricular tachycardia, age, and congestive heart failure. Patients with LBBB who converted from normal axis to LAD had significantly higher mortality in time-to-event analysis (p = 0.02). In conclusion, in patients with LBBB, LAD does not confer significant mortality risk. However, those with normal axis who developed LAD during the study period had significantly higher mortality. Perhaps when LBBB and LAD develop concurrently, there is no increased risk over baseline LBBB development, but it may herald a worse prognosis if LAD develops against the background of previous LBBB, from an unknown mechanism. PMID:23642510

Patel, Parin J; Verdino, Ralph J

2013-08-01

103

[ECG QRS signal detection and control system design of ventricular assist device].  

PubMed

In order to achieve auxiliary timing of ventricular assisting device to automatically track the ECG signals, we designed a set of ECG acquisition circuit in our study for the first time. Then we carried out ECG acquisition, smoothing filter and QRS detection on the LabVIEW. With the QRS signal as a benchmark, the control system immediately triggered ventricular assisting device to trigger the heart to contract for ejection for about 300 ms, and then to assist to make it relax. The practical effects of the experiment proved that ECG acquisition circuit had the feature of strong anti-interference, and control system had no false QRS detection and no false triggering of assist device. This achieves the auxiliary timing which could automatically track the ECG signal. PMID:23865330

Liao, Huogen; Yang, Ming; Zhuang, Xiaoqi; Huang, Huan

2013-06-01

104

Real-time electrocardiogram P-QRS-T detection-delineation algorithm based on quality-supported analysis of characteristic templates.  

PubMed

The main objective of this study is to introduce a simple, low-latency, and accurate algorithm for real-time detection of P-QRS-T waves in the electrocardiogram (ECG) signal. In the proposed method, real-time signal preprocessing, which includes high frequency noise filtering and baseline wander reduction, is performed by applying discrete wavelet transform (DWT). A method based on signal first-order derivative and adaptive threshold adjustment is employed for real-time detection of the QRS complex. Moreover, detection and delineation of P- and T-waves are achieved by correlation analysis conducted between signal and their templates. Besides, signal quality is investigated online, and if the quality of the analysis window is unacceptable, then the algorithm will guess (estimate) the locations of P- and T-waves. The operating characteristics of the proposed algorithm are evaluated by its implementation to an artificially generated ECG signal whose quality is adjustable from the best (Quality, 100%) to the worst (Quality, ?40%) cases based on the random-walk noise theory. The algorithm was applied to the MIT-BIH arrhythmia database, QT database, and Physionet/CinC challenge 2011competition database. The obtained results, which were based on the QT database, showed sensitivity and positive predictivity of Se=99.63% and P+=99.83%, Se=99.83% and P+=99.98%, and Se=99.74% and P+=99.89% for the detection of P-, QRS-, and T-waves, respectively, and the obtained results, which were based on the MIT-BIH arrhythmia database, showed Se=99.81% and P+=99.70% for the detection of the QRS complex. Moreover, it will be shown that the results of the proposed method are reliable for a minimum signal quality value of 70%. According to numerical assessments, 8-ms after the occurrence of R-wave, its location will be identified by the computer code of the proposed algorithm. This parameter is 198-ms and 177-ms for P- and T-waves, respectively. PMID:25063881

Karimipour, Atiyeh; Homaeinezhad, Mohammad Reza

2014-09-01

105

Comparative Effectiveness of Cardiac Resynchronization Therapy in Combination With Implantable Defibrillator in Patients With Heart Failure and Wide QRS Duration.  

PubMed

Several clinical trials have established that cardiac resynchronization therapy in combination with an implantable cardioverter-defibrillator improves survival and alleviates heart failure symptoms in appropriately selected patients. Recent guidelines have expanded the indications to include patients with less severe heart failure. The aim of this study was to examine the extent to which cardiac resynchronization therapy in combination with an implantable cardioverter-defibrillator improves survival and reduces risk for heart failure hospitalization in United States Medicare patients who met class I or class IIa recommendations. Propensity score methods were used to assess survival and rehospitalization outcomes in Medicare patients. Among patients who met class I recommendations, those with combined cardiac resynchronization therapy had significantly lower risk for death (hazard ratio [HR] 0.83, 95% confidence interval [CI] 0.77 to 0.88, p <0.0001) and lower risk for rehospitalization (HR 0.88, 95% CI 0.83 to 0.94, p <0.0001). Among patients who met class IIa recommendations, the relative hazard of death for patients with combined cardiac resynchronization therapy was lower (HR 0.90, 95% CI 0.85 to 0.96, p = 0.0015), but there was no significant difference in the risk for rehospitalization for heart failure (HR 1.03, 95% CI 0.97 to 1.10, p = 0.2600). In conclusion, cardiac resynchronization therapy in combination with an implantable cardioverter-defibrillator resulted in improved survival among Medicare patients meeting class I criteria and most patients meeting class IIa criteria as outlined in the current guidelines for device-based therapy in heart failure, although the effect sizes were lower than those demonstrated in recent trials. PMID:25240510

Bilchick, Kenneth C; Stukenborg, George J

2014-11-15

106

Does Maturity Affect Cephalic Perfusion and T/QRS Ratio during Prolonged Umbilical Cord Occlusion in Fetal Sheep?  

PubMed Central

T/QRS ratio monitoring is used to help identify fetal asphyxia. However, immature animals have greater capacity to maintain blood pressure during severe asphyxia, raising the possibility that they may show an attenuated T/QRS increase during asphyxia. Chronically instrumented fetal sheep at 0.6 of gestation (0.6?GA; n = 12), 0.7?GA (n = 12), and 0.8?GA (n = 8) underwent complete umbilical cord occlusion for 30?min, 25?min, or 15?min, respectively. Cord occlusion was associated with progressive metabolic acidosis and initial hypertension followed by severe hypotension, with a more rapid fall in mean arterial blood pressure (MAP) and carotid blood flow (CaBF) with advancing gestation. T/QRS ratio rose after occlusion more rapidly at 0.8?GA than in immature fetuses, to a similar final peak at all ages, followed by a progressive fall that was slower at 0.8?GA than in the immature fetuses. The increase in T/QRS ratio correlated with initial hypertension at 0.8?GA (P < 0.05, R2 = 0.38), and conversely, its fall correlated closely with falling MAP in all gestational groups (P < 0.01, R2 = 0.67). In conclusion, elevation of the T/QRS ratio is an index of onset of severe asphyxia in the last third of gestation, but not of fetal compromise. PMID:24693290

Drury, Paul P.; Gunn, Eleanor R.; Bennet, Laura; Gunn, Alistair J.

2014-01-01

107

The Correlation between Infarct Size and the QRS Axis Change after Thrombolytic Therapy in ST Elevation Acute Myocardial Infarction  

PubMed Central

Objective: Electrocardiography (ECG) may be a practical guiding tool for prognostic infarct sizing in ST elevation acute myocardial infarction (STEAMI). In this study, we sought to find a relation between the infarct size and the change in the QRS axis after thrombolytic therapy. Materials and Methods: Patients with STEAMI who received thrombolytic therapy were selected retrospectively. The mean QRS axes of two ECGs (before and 90 minutes after thrombolytic therapy) were calculated. Creatinine kinase MB (CKMB) was used as the marker of infarct size. Results: We did not detect any correlation between infarct size and change in the QRS axis with respect to any myocardial infarction MI localizations (p=0.80). However, in the isolated inferior MI group, there was a good correlation between CKMB and change in the QRS axis (r=?0.52 p=0.049). Conclusion: The change in the QRS axis is rarely emphasized, providing a practical and promising tool for evaluating both the efficiency of the thrombolytic therapy and prognostic infarct sizing.

Karakas, M. Fatih; Bilen, Emine; Kurt, Mustafa; Arslantas, Ugur; Ipek, Gokturk; Karakas, Esra; Yuksel, Isa Oner; Yasar, Ayse Saatc?; Bilge, Mehmet

2012-01-01

108

Quantifying QRS changes during myocardial ischemia: Insights from high frequency electrocardiography.  

PubMed

Over four decades of high frequency electrocardiography research have provided a body of knowledge about QRS changes during myocardial ischemia, and the techniques to measure and quantify them. High-frequency QRS (HFQRS) components, being closely related to the pattern of ventricular depolarization, carry valuable clinical information. Changes in HFQRS amplitude and morphology have been shown to be sensitive diagnostic markers of myocardial ischemia, often superior to measures of ST-T segment changes. Clinical studies in patients undergoing exercise testing have consistently demonstrated the incremental diagnostic value of HFQRS analysis in detection of demand ischemia. In 6 studies that evaluated the HyperQ™ technology, the average sensitivity and specificity of HFQRS analysis were 75%±6% and 80%±6%, respectively, compared to average sensitivity 48%±16% and average specificity 70%±15% of ST segment analysis. In patients with acute supply ischemia, recent studies characterized and quantified the ischemic HFQRS patterns. HFQRS morphology index was found to be higher in patients with acute coronary syndrome (ACS), compared to non-ischemic, with good sensitivity in patients without ST elevation. These research findings may be translated into commercially-available ECG systems and be used in clinical practice for improved diagnosis and monitoring of myocardial ischemia. PMID:24795285

Amit, Guy; Granot, Yair; Abboud, Shimon

2014-01-01

109

Use of the Questionnaire on Resources and Stress (QRS-F) with parents of young children with autism  

Microsoft Academic Search

The Questionnaire on Resources and Stress (Friedrich, short form: QRS-F) has been used widely with parents of children with disabilities. However, its psychometric properties in parents of young children with autism have not been established. Here, 174 mothers and 43 fathers of children under 6 years with autism spectrum disorder were studied by two independent research teams. Each parent completed

Emma Honey; Richard P. Hastings; Helen Mcconachie

2005-01-01

110

When Deriving the Spatial QRS-T Angle from the 12-lead ECG, which Transform is More Frank: Regression or Inverse Dower?  

NASA Technical Reports Server (NTRS)

Our primary objective was to ascertain which commonly used 12-to-Frank-lead transformation yields spatial QRS-T angle values closest to those obtained from simultaneously collected true Frank-lead recordings. Simultaneous 12-lead and Frank XYZ-lead recordings were analyzed for 100 post-myocardial infarction patients and 50 controls. Relative agreement, with true Frank-lead results, of 12-to-Frank-lead transformed results for the spatial QRS-T angle using Kors regression versus inverse Dower was assessed via ANOVA, Lin s concordance and Bland-Altman plots. Spatial QRS-T angles from the true Frank leads were not significantly different than those derived from the Kors regression-related transformation but were significantly smaller than those derived from the inverse Dower-related transformation (P less than 0.001). Independent of method, spatial mean QRS-T angles were also always significantly larger than spatial maximum (peaks) QRS-T angles. Spatial QRS-T angles are best approximated by regression-related transforms. Spatial mean and spatial peaks QRS-T angles should also not be used interchangeably.

Schlegel, Todd T.; Cortez, Daniel

2010-01-01

111

Duration tuning across vertebrates.  

PubMed

Signal duration is important for identifying sound sources and determining signal meaning. Duration-tuned neurons (DTNs) respond preferentially to a range of stimulus durations and maximally to a best duration (BD). Duration-tuned neurons are found in the auditory midbrain of many vertebrates, although studied most extensively in bats. Studies of DTNs across vertebrates have identified cells with BDs and temporal response bandwidths that mirror the range of species-specific vocalizations. Neural tuning to stimulus duration appears to be universal among hearing vertebrates. Herein, we test the hypothesis that neural mechanisms underlying duration selectivity may be similar across vertebrates. We instantiated theoretical mechanisms of duration tuning in computational models to systematically explore the roles of excitatory and inhibitory receptor strengths, input latencies, and membrane time constant on duration tuning response profiles. We demonstrate that models of duration tuning with similar neural circuitry can be tuned with species-specific parameters to reproduce the responses of in vivo DTNs from the auditory midbrain. To relate and validate model output to in vivo responses, we collected electrophysiological data from the inferior colliculus of the awake big brown bat, Eptesicus fuscus, and present similar in vivo data from the published literature on DTNs in rats, mice, and frogs. Our results support the hypothesis that neural mechanisms of duration tuning may be shared across vertebrates despite species-specific differences in duration selectivity. Finally, we discuss how the underlying mechanisms of duration selectivity relate to other auditory feature detectors arising from the interaction of neural excitation and inhibition. PMID:22553042

Aubie, Brandon; Sayegh, Riziq; Faure, Paul A

2012-05-01

112

A 300-mV 220-nW Event-Driven ADC With Real-Time QRS Detection for Wearable ECG Sensors.  

PubMed

This paper presents an ultra-low-power event-driven analog-to-digital converter (ADC) with real-time QRS detection for wearable electrocardiogram (ECG) sensors in wireless body sensor network (WBSN) applications. Two QRS detection algorithms, pulse-triggered (PUT) and time-assisted PUT (t-PUT), are proposed based on the level-crossing events generated from the ADC. The PUT detector achieves 97.63% sensitivity and 97.33% positive prediction in simulation on the MIT-BIH Arrhythmia Database. The t-PUT improves the sensitivity and positive prediction to 97.76% and 98.59% respectively. Fabricated in 0.13 ?m CMOS technology, the ADC with QRS detector consumes only 220 nW measured under 300 mV power supply, making it the first nanoWatt compact analog-to-information (A2I) converter with embedded QRS detector. PMID:25608283

Zhang, Xiaoyang; Lian, Yong

2014-12-01

113

Usefulness of electrocardiographic QRS/T angles with versus without bundle branch blocks to predict heart failure (from the Atherosclerosis Risk in Communities Study).  

PubMed

Repolarization abnormalities in the setting of bundle branch blocks (BBB) are generally ignored. We used Cox regression models to determine hazard ratios (HRs) with 95% confidence intervals (CIs) for incident heart failure (HF) associated with wide spatial and frontal QRS/T angle (upper twenty-fifth percentile of each) in men and women with and without BBB. This analysis included 14,478 participants (54.6% women, 26.4% blacks, 377 [2.6%] with BBB) from the Atherosclerosis Risk in Communities Study who were free of HF at baseline. Using No-BBB with normal spatial QRS/T angle as the reference group, the risk for HF in multivariable adjusted models was increased 51% for No-BBB with wide spatial QRS/T angle (HR 1.51, 95% CI 1.37 to 1.66), 48% for BBB with normal spatial QRS/T angle (HR 1.48, 95% CI 1.17 to 1.88), and the risk for incident HF was increased more than threefold for BBB with wide spatial QRS/T angle (HR 3.37, 95% CI 2.47 to 4.60). The results were consistent across subgroups by gender. Similar results were observed for the frontal plane QRS/T angle. In the pooled BBB group excluding right BBB, a positive T wave in lead aVR and heart rate 70 bpm and higher were also potent predictors of incident HF similar to the QRS/T angles. In conclusion, both BBB and wide QRS/T angles are predictive of HF, and concomitant presence of both carries a much higher risk than for either predictor alone. These findings suggest that repolarization abnormalities in the setting of BBB should not be considered benign or an expected consequence of BBB. PMID:24929625

Zhang, Zhu-ming; Rautaharju, Pentti M; Prineas, Ronald J; Loehr, Laura; Rosamond, Wayne; Soliman, Elsayed Z

2014-08-01

114

A vector-free ECG interpretation with P, QRS & T waves as unbalanced transitions between stable configurations of the heart electric field during P-R, S-T & T-P segments  

PubMed Central

Since cell membranes are weak sources of electrostatic fields, this ECG interpretation relies on the analogy between cells and electrets. It is here assumed that cell-bound electric fields unite, reach the body surface and the surrounding space and form the thoracic electric field that consists from two concentric structures: the thoracic wall and the heart. If ECG leads measure differences in electric potentials between skin electrodes, they give scalar values that define position of the electric field center along each lead. Repolarised heart muscle acts as a stable positive electric source, while depolarized heart muscle produces much weaker negative electric field. During T-P, P-R and S-T segments electric field is stable, only subtle changes are detectable by skin electrodes. Diastolic electric field forms after ventricular depolarization (T-P segments in the ECG recording). Telediastolic electric field forms after the atria have been depolarized (P-Q segments in the ECG recording). Systolic electric field forms after the ventricular depolarization (S-T segments in the ECG recording). The three ECG waves (P, QRS and T) can then be described as unbalanced transitions of the heart electric field from one stable configuration to the next and in that process the electric field center is temporarily displaced. In the initial phase of QRS, the rapidly diminishing septal electric field makes measured potentials dependent only on positive charges of the corresponding parts of the left and the right heart that lie within the lead axes. If more positive charges are near the "DOWN" electrode than near the "UP" electrode, a Q wave will be seen, otherwise an R wave is expected. Repolarization of the ventricular muscle is dampened by the early septal muscle repolarization that reduces deflection of T waves. Since the "UP" electrode of most leads is near the usually larger left ventricle muscle, T waves are in these leads positive, although of smaller amplitude and longer duration than the QRS wave in the same lead. The proposed interpretation is applied to bundle branch blocks, fascicular (hemi-) blocks and changes during heart muscle ischemia. PMID:24506945

2014-01-01

115

Electrocradiographic Qrs Axis, Q Wave and T-wave Changes in 2nd and 3rd Trimester of Normal Pregnancy  

PubMed Central

Background: Pregnancy although a physiological phenomena affects all the functions of the maternal body and brings about remarkable changes in the cardiovascular system. The cardiovascular changes and many of the physiological adaptations of normal pregnancy alter the physical findings thus, sometimes misleading the diagnosis of heart disease. Pregnancy also brings about various changes in the electrocardiogram, further confusing with that of heart disease. This study is undertaken to highlight the effect of normal pregnancy on the QRS axis, Q wave and T-wave of the Electrocardiogram and thereby helps us to distinguish it from that of pathological changes. Objectives: To study the effect of normal pregnancy on the QRS axis, Q wave and T-wave in the electrocardiogram and to compare with that of normal non pregnant women. Materials and Methods: Fifty normal pregnant women in 2nd and 3rd trimester each between 20– 35 y of age and 50 normal non pregnant women of the same age group were selected for the study. A 12 lead ECG was recorded by using ECG machine with special emphasis on QRS axis, Q wave and T-wave changes and all the parameters were analysed. Results: The ECG changes observed in our study include, deviation of QRS axis towards left as pregnancy advanced, significant increased incidence of occurrence of prominent Q waves in lead II, III and avF in pregnant group (p < 0.05 ) and, T-wave abnormalities like flat and inverted T-waves in lead III, V1 – V3 were more frequent in pregnant group ( p<0.05 ) than in non pregnant group. Conclusion:Normal pregnancy brings about various changes in ECG. These changes during pregnancy should be interpretated with caution by the physicians. It is necessary to understand the normal physiological changes which in turn help us in better management of those with cardiac disease. PMID:25386425

S., Chandrasekharappa; Brid, S.V

2014-01-01

116

[Evaluation of electrocardiographic left ventricular hypertrophy with both QRS voltage and ST-T change using echocardiography].  

PubMed

The purpose of the present study is to determine whether electrocardiographic QRS voltage criteria with ST-T change is useful in the diagnosis of left ventricular hypertrophy (LVH) using echocardiography. One hundred men including 59 with hypertension (HT), 9 with hypertrophic cardiomyopathy (HCM), and 32 without any cardiovascular disease were enrolled in this study. All of them had the electrocardiographic evidence of LVH by Sokolow-Lyon voltage criteria (RV5 or RV6 > 2.6 mV, SV1+RV5 or SV1+RV6 > or = 3.5 mV). They were classified into three groups based on ST-T pattern as follows: Normal ST-T (group N): normal ST-T in twelve leads; Early strain ST-T (group ES): ST depression, flat T (T/R < 1/10), diphasic T or T wave inversion < 0.1 mV in V5 or V6; and Strain ST-T (group S): inverted T wave in V5 and V6. Echocardiographic LVH was determined when either interventricular septal thickness (IVST) or left ventricular posterior wall thickness (LVPWT) > or = 12 mm was present. According to this echocardiographic evidence, 31.7%(20/63) of group N, 75.0% (12/16) of group ES, and 100% (21/21) of group S were diagnosed. There were significant correlations between QRS voltage indices (RV5, RV6, SV1+RV5 and SV1+RV6) and IVST, (IVST+LVPWT)/2, and LV mass in group S(r = 0.650 to 0.858, p < 0.05) but not in group N. Values for IVST and LV mass were significantly greater in group S than in group ES or N. The electrocardiographic diagnosis of LVH with both QRS voltage and ST-T change thus appeared to be more useful than that with QRS voltage criteria alone. PMID:9283227

Yagi, T; Noda, A; Itoh, R; Yamada, H; Nakashima, N; Yokota, M

1997-08-01

117

Implications of Franciscan Complex graywacke geochemistry for sediment transport, provenance determination, burial-exposure duration, and fluid exchange with cosubducted metabasites  

NASA Astrophysics Data System (ADS)

of graywacke provenance has long been used to evaluate the record of tectonic process in orogenic belts. Our geochemical data from graywackes of the Franciscan subduction complex, California, show that the connection between sedimentary record and geologic processes may be more complex than previously believed. Trace elements and Nd-Sr-Pb isotopes of Franciscan graywackes indicate two sources types. One group lacking negative Eu anomaly (Eu/Eu* > 0.9), shows slightly concave-up heavy rare earth elements, arc-like trace element patterns, and western Pacific island arc-like Pb isotopes, reflecting derivation from older accreted oceanic-arc terranes in the Sierra Nevada-Klamath Mountains. The other group displays small negative Eu anomalies, with trace element patterns resembling post-Archean Australian shale and Pb isotopes similar to Jurassic-Cretaceous Sierran batholith. There is no systematic separation of these two groups by depositional ages. Thus, geochemistry of the graywackes may partly reflect variation in location of sediment delivery systems, rather than solely reflecting evolution of the neighboring arc. Variation of Nd-Sr isotopes with stratigraphic-age for the graywackes mimics the trends of the coeval Great Valley Group clastic-rocks, suggesting that (1) they share the same sediment sources, (2) there are no "exotic" sediment sources that fed the Franciscan trench, and (3) burial-exposure cycles for Franciscan clastic rocks were comparatively brief. Comparison of Franciscan graywacke and metabasite geochemistry corroborates earlier conclusions that metabasites had little or no chemical exchange with fluids from cosubducted graywacke. Detrital zircon age populations, major element chemistry, and detrital framework modes, when compared to our data suggest that the former three parameters underrepresent the mafic component of clastic sediment provenance.

Ghatak, Arundhuti; Basu, Asish R.; Wakabayashi, John

2013-09-01

118

Word Durations in Non-Native English  

PubMed Central

In this study, we compare the effects of English lexical features on word duration for native and non-native English speakers and for non-native speakers with different L1s and a range of L2 experience. We also examine whether non-native word durations lead to judgments of a stronger foreign accent. We measured word durations in English paragraphs read by 12 American English (AE), 20 Korean, and 20 Chinese speakers. We also had AE listeners rate the `accentedness' of these non-native speakers. AE speech had shorter durations, greater within-speaker word duration variance, greater reduction of function words, and less between-speaker variance than non-native speech. However, both AE and non-native speakers showed sensitivity to lexical predictability by reducing second mentions and high frequency words. Non-native speakers with more native-like word durations, greater within-speaker word duration variance, and greater function word reduction were perceived as less accented. Overall, these findings identify word duration as an important and complex feature of foreign-accented English. PMID:21516172

Baker, Rachel E.; Baese-Berk, Melissa; Bonnasse-Gahot, Laurent; Kim, Midam; Van Engen, Kristin J.; Bradlow, Ann R.

2010-01-01

119

Prevalence and prognostic significance of low QRS voltage among the three main types of cardiac amyloidosis.  

PubMed

Low voltage is classically reported as an electrocardiographic (ECG) finding in cardiac amyloidosis (CA). We evaluated electrocardiograms to determine the prevalence of low voltage and its association with outcomes. Electrocardiograms in 200 patients with CA were reviewed. The presence of low voltage was assessed by all limb leads?0.5 mV, all precordial leads?1.0 mV, or Sokolow index?.5 mV, and the association with time to adverse outcomes, including hospitalization, orthotopic heart transplant, and death, was assessed by the Cox proportional hazards model. Low voltage prevalence was 60% when using Sokolow index?.5 mV, 34% by QRS amplitude?0.5 mV in each limb lead, and 13% when ?1.0 mV in each precordial lead with no differences in prevalence noted by the type of amyloid. Apart from atrial fibrillation and second-degree atrioventricular block being more common in wild type transthryretin cardiac amyloid (ATTRwt), the prevalence of ECG findings was similar among the 3 types of amyloid. Sokolow?1.5 mV (HR 1.690; 95% CI of 1.069 to 2.672; p=0.0246) was independently associated with adverse outcomes. In conclusion, among the 3 main types of CA, the prevalence of low voltage is dependent on the method used for defining low voltage. Sokolow index?1.5 mV indicated the highest prevalence and was associated with adverse outcomes in CA. Our data suggest that low voltage is a relatively late finding in CA and may not be useful for early identification. PMID:25212550

Cyrille, Nicole B; Goldsmith, Jeff; Alvarez, Julissa; Maurer, Mathew S

2014-10-01

120

The relationship of QRS morphology and mechanical dyssynchrony to long-term outcome following cardiac resynchronization therapy  

PubMed Central

Aims Because benefits of cardiac resynchronization therapy (CRT) appear to be less favourable in non-left bundle branch block (LBBB) patients, this prospective longitudinal study tested the hypothesis that QRS morphology and echocardiographic mechanical dyssynchrony were associated with long-term outcome after CRT. Methods and results Two-hundred and seventy-eight consecutive New York Heart Association class III and IV CRT patients with QRS ?120 ms and ejection fraction ?35% were studied. The pre-specified primary endpoint was death, heart transplant, or left ventricular assist device over 4 years. Dyssynchrony assessed before CRT included interventricular mechanical delay (IVMD) and speckle-tracking radial strain using pre-specified cut-offs for each. Of 254 with baseline quantitative echocardiographic data available, 128 had LBBB, 81 had intraventricular conduction delay (IVCD), and 45 had right bundle branch block (RBBB). Radial dyssynchrony was observed in 85% of the patients with LBBB, 59% with IVCD*, and 40% with RBBB* (*P < 0.01 vs. LBBB). Of 248 (98%) with follow-up, LBBB patients had a significantly more favourable long-term survival than non-LBBB patients. However, non-LBBB patients with dyssynchrony had a more favourable event-free survival than those without dyssynchrony: radial dyssynchrony hazard ratio 2.6, 95% confidence interval (CI) 1.47–4.53 (P = 0.0008) and IVMD hazard ratio 4.9, 95% CI 2.60–9.16 (P = 0.0007). Right bundle branch block patients who lacked dyssynchrony had the least favourable outcome. Conclusion Non-LBBB patients with dyssynchrony had a more favourable long-term survival than non-LBBB patients who lacked dyssynchrony. Mechanical dyssynchrony and QRS morphology are associated with outcome following CRT. PMID:22351700

Hara, Hideyuki; Oyenuga, Olusegun A.; Tanaka, Hidekazu; Adelstein, Evan C.; Onishi, Toshinari; McNamara, Dennis M.; Schwartzman, David; Saba, Samir; Gorcsan, John

2012-01-01

121

Prevalence and inter-relationship of different Doppler measures of dyssynchrony in patients with heart failure and prolonged QRS: a report from CARE-HF  

Microsoft Academic Search

BACKGROUND: Cardiac resynchronisation therapy (CRT) improves mortality and morbidity in heart failure patients with wide QRS. Observational studies suggest that patients having more left ventricular dyssynchrony pre-implantation obtain greater benefit on ventricular function and symptoms with CRT. AIM: To provide an analysis of the prevalence and type of dyssynchrony in patients included in the CARE-HF trial. METHODS: 100 patients 67

Magnus Edner; Yong Kim; Knud Norregaard Hansen; Henrik Nissen; Geert Espersen; Karl La Rosee; Fikru Maru; Nick Freemantle; John Cleland; Peter Sogaard

2009-01-01

122

Long duration flights management  

NASA Astrophysics Data System (ADS)

Long duration flights (LDF) require a special management to take the best decisions in terms of ballast consumption and instant of separation. As a contrast to short duration flights, where meteorological conditions are relatively well known, for LDF we need to include the meteorological model accuracy in trajectory simulations. Dispersions on the fields of model (wind, temperature and IR fluxes) could make the mission incompatible with safety rules, authorized zones and others flight requirements. Last CNES developments for LDF act on three main axes: 1. Although ECMWF-NCEP forecast allows generating simulations from a 4D point (altitude, latitude, longitude and UT time), result is not statistical, it is determinist. To take into account model dispersion a meteorological NCEP data base was analyzed. A comparison between Analysis (AN) and Forecast (FC) for the same time frame had been done. Result obtained from this work allows implementing wind and temperature dispersions on balloon flight simulator. 2. For IR fluxes, NCEP does not provide ascending IR fluxes in AN mode but only in FC mode. To obtain the IR fluxes for each time frame, satellite images are used. A comparison between FC and satellites measurements had been done. Results obtained from this work allow implementing flux dispersions on balloon flight simulator. 3. An improved cartography containing a vast data base had been included in balloon flight simulator. Mixing these three points with balloon flight dynamics we have obtained two new tools for observing balloon evolution and risk, one of them is called ASTERISK (Statistic Tool for Evaluation of Risk) for calculations and the other one is called OBERISK (Observing Balloon Evolution and Risk) for visualization. Depending on the balloon type (super pressure, zero pressure or MIR) relevant information for the flight manager is different. The goal is to take the best decision according to the global situation to obtain the largest flight duration with a minimum risk for population. Telemetry system is based on satellite communication technologies. Housekeeping data and GPS data are transferred to the Ground Station by IRIDIUM network. Gondola is interrogated automatically each hour and all data stocked onboard are downloaded to ground station. Communication takes a few minutes to transfer all data stocked from last request. Tools had been used in SCOUT-MIR campaign 2008 for the first time. The results obtained encourage CNES teams to improve ergonomics and functionalities of these prototype.

Sosa-Sesma, Sergio; Letrenne, Gérard; Spel, Martin; Charbonnier, Jean-Marc

123

Sequential biventricular pacing improves regional contractility, longitudinal function and dyssynchrony in patients with heart failure and prolonged QRS  

PubMed Central

Aims Biventricular pacing (BiP) is an effective treatment in systolic heart failure (HF) patients with prolonged QRS. However, approximately 35% of the patients receiving BiP are classified as non-responders. The aim of this study is to evaluate the acute effects of VV-optimization on systolic heart function. Methods Twenty-one HF patients aged 72 (46-88) years, QRS 154 (120-190) ms, were studied with echocardiography, Tissue Doppler Imaging (TDI) and 3D-echo the first day after receiving a BiP device. TDI was performed; during simultaneous pacing (LV-lead pacing 4 ms before the RV-lead) and during sequential pacing (LV 20 and 40 ms before RV and RV 20 and 40 ms before LV-lead pacing). Systolic heart function was studied by tissue tracking (TT) for longitudinal function and systolic maximal velocity (SMV) for regional contractility and signs of dyssynchrony assessed by time-delays standard deviation of aortic valve opening to SMV, AVO-SMV/SD and tissue synchronization imaging (TSI). Results The TT mean value preoperatively was 4,2 ± 1,5 and increased at simultaneous pacing to 5,0 ± 1,2 mm (p < 0,05), and at best VV-interval to 5,4 ± 1,2 (p < 0,001). Simultaneous pacing achieved better TT distance compared with preoperative in 16 patients (76%). However, it was still higher after VV-optimization in 12 patients 57%. Corresponding figures for SMV were 3,0 ± 0,7, 3,5 ± 0,8 (p < 0,01), and 3,6 ± 0,8 (p < 0,001). Also dyssynchrony improved. Conclusions VV-optimization in the acute phase improves systolic heart function more than simultaneous BiP pacing. Long-term effects should be evaluated in prospective randomized trials. PMID:20384995

2010-01-01

124

Long duration ash probe  

DOEpatents

A long duration ash probe includes a pressure shell connected to a port in a combustor with a sample coupon mounted on a retractable carriage so as to retract the sample coupon within the pressure shell during sootblowing operation of the combustor. A valve mounted at the forward end of the pressure shell is selectively closeable to seal the sample coupon within the shell, and a heating element in the shell is operable to maintain the desired temperature of the sample coupon while retracted within the shell. The carriage is operably mounted on a pair of rails within the shell for longitudinal movement within the shell. A hollow carrier tube connects the hollow cylindrical sample coupon to the carriage, and extends through the carriage and out the rearward end thereof. Air lines are connected to the rearward end of the carrier tube and are operable to permit coolant to pass through the air lines and thence through the carrier tube to the sample coupon so as to cool the sample coupon.

Hurley, John P. (Grand Forks, ND); McCollor, Don P. (Grand Forks, ND); Selle, Stanley J. (Grand Forks, MN)

1994-01-01

125

The time and duration of meiosis.  

PubMed

Ever since meiosis was recognized as a process there has been a continuing interest in its temporal aspects. Two main types of meiotic timing experiments have been conducted: first, experiments to estimate the duration of meiosis (and sometimes its stages); second, experiments to locate the sensitive stage(s) when exposure of meiocytes to various treatments can affect meiotic chromosome behaviour (e.g. pairing or recombination). Such experiments have played an important role in increasing our understanding of the meiotic process. The duration of meiosis has been estimated in about 70 organisms, including two prokaryotes (yeast and Chlamydomonas) and the following eukaryotes: 1 Basidiomycete (Coprinus lagopus), 2 Gymnosperms (Larix decidua and Thuja plicata gracilis). at least 39 angiosperms, and at least 26 animal species. The duration of female meiosis has been estimated in far fewer species than male meiosis. However, estimates of the duration of female meiosis are available for 6 angiosperms. Drosophila melanogaster, Xenopus laevis, and several mammals. Comparison of these data shows that the duration of meiosis is one of the most variable aspects of the meiotic process, ranging from less than 6 h in yeast to more than 40 years in the human female. Developmental holds at different stages of meiosis are common in plants and animals, and inevitably prolong the meiotic division. However, even among species without developmental holds, the duration of meiosis is very variable. For instance, in animals it ranges from about 1-2 days in male Drosophila melanogaster to more than 24 days in male Homo sapiens and several Orthopterans. Despite the large variation in the duration of meiosis three generalizations can be made: (i) first prophase is always very long compared with the remaining meiotic stages, (ii) the rate of meiotic development is very slow compared with the rate of development in dividing somatic meristem cells of the same organisms under the same conditions, (iii) the duration of meiosis is characteristic of the genotype and species. Four main factors have been recognized which effect or determine the duration of meiosis, namely (1) environmental factors (e.g. temperature); (2) nuclear DNA content; (3) ploidy level of the organism; and, (4) the genotype. Because nuclear DNA content plays a major role in determining the duration of meiosis, it has been suggested that DNA influences the rate of meiotic development in two ways: first through its informational content (the genotype), and second indirectly by the physical and mechanical effects of its mass independently of its informational content (i.e. the nucleotype). Thus, the observed duration of meiosis is the result of a complex genotype-nucleotype-environment interaction. With the obvious exception of variation caused by developmental holds, changes in the duration of meiosis usually involve proportional changes in the durations of all its stages... PMID:16285

Bennett, M D

1977-03-21

126

Duration estimation entails predicting when.  

PubMed

The estimation of duration can be affected by context and surprise. Using MagnetoEncephaloGraphy (MEG), we tested whether increased neural activity during surprise and following neural suppression in two different contexts supported subjective time dilation (Eagleman and Pariyadath, 2009; Pariyadath and Eagleman, 2012). Sequences of three 300ms frequency-modulated (FM, control) or pure tones (test) were presented and followed by a fourth FM varying in duration. In test, the last FM was perceived as significantly longer than veridical duration (Tse et al., 2004) but did not differ from the perceived duration in control. Several novel and distinct neural signatures were observed in duration estimation: first, neural suppression of standard stimuli was observed for the onset but not for the offset auditory evoked responses. Second, ramping activity increased with veridical duration in control whereas at the same latency in test, the amplitude of the midlatency response increased with the distance of deviant durations. Third, in both conditions, the amplitude of the offset auditory evoked responses accounted well for participants' performance: the longer the perceived duration, the larger the offset response. Fourth, neural duration demarcated by the peak latencies of the onset and ramping evoked activities indexed a systematic time compression that reliably predicted subjective time perception. Our findings suggest that interval timing undergoes time compression by capitalizing on the predicted offset of an auditory event. PMID:25462792

van Wassenhove, Virginie; Lecoutre, Lucille

2015-02-01

127

ESTIMATING THE DURATION OF SPECIATION FROM PHYLOGENIES  

PubMed Central

Speciation is not instantaneous but takes time. The protracted birth–death diversification model incorporates this fact and predicts the often observed slowdown of lineage accumulation toward the present. The mathematical complexity of the protracted speciation model has barred estimation of its parameters until recently a method to compute the likelihood of phylogenetic branching times under this model was outlined (Lambert et al. 2014). Here, we implement this method and study using simulated phylogenies of extant species how well we can estimate the model parameters (rate of initiation of speciation, rate of extinction of incipient and good species, and rate of completion of speciation) as well as the duration of speciation, which is a combination of the aforementioned parameters. We illustrate our approach by applying it to a primate phylogeny. The simulations show that phylogenies often do not contain enough information to provide unbiased estimates of the speciation-initiation rate and the extinction rate, but the duration of speciation can be estimated without much bias. The estimate of the duration of speciation for the primate clade is consistent with literature estimates. We conclude that phylogenies combined with the protracted speciation model provide a promising way to estimate the duration of speciation. PMID:24758256

Etienne, Rampal S; Morlon, Hélène; Lambert, Amaury

2014-01-01

128

Poverty Durations and Poverty Measurement  

Microsoft Academic Search

Abstract Currently available measures of poverty typically usean annual accounting period, which implicitly ignores both the duration of deprivation experience within a particular year and after or before the year in question. This article argues that since the incomes,of the poor often fluctuate within a year, and since long duration poverty is of great social concern, measures of aggregate poverty

Lars Osberg; Kuan Xu

129

Duration of the 2011 Tohoku earthquake ground motions  

NASA Astrophysics Data System (ADS)

We compared several different duration measures for the 2011 M9.0 Tohoku earthquake sequence, because empirical duration models are of great interest for purposes of correlation with structural damage, and the Tohoku mainshock was remarkable for its long duration. Among the three considered definitions, RMS duration (McCann and Shah, Bull Seism Soc Am 69: 1253-1265, 1979) is best able to predict the duration within which pulses or groups of pulses of energy arrive; it is particularly suitable for the Tohoku mainshock, for which source complexity caused time-series with multiple-phase arrivals. Two other considered definitions, both of which tend to underestimate the observed duration, are: (i) duration defined by random vibration theory (RVT); and (ii) the significant duration as defined by the interval between 5 and 75 % or 95 % of the integral of the square of the ground acceleration (known as "Arias intensity" (Arias 1970)) or velocity (known as "energy integral" (Anderson 2004)). In the Tohoku mainshock, significant amplitudes precede the 5 % of the Arias intensity marker; we need to use 0.3 % of the maximum of the accumulated energy as the lower bound marker to appropriately estimate the duration using the significant duration definition. The RVT duration (used in stochastic simulations) can be estimated easily from the 5-75 % of the Arias intensity (significant duration) definition as the two measures give very similar durations. Overall, the significant duration of ground motions observed during the 2011 M9.0 Tohoku earthquake increases with distance as 0.19 R cd for the horizontal components or 0.33 R cd for the vertical component, where R cd is the closest distance to the fault plane. By comparison, the duration of four aftershocks ( M4.5-7.7) increases with distance as ~0.10 R hypo where R hypo is the hypocentral distance. For the mainshock, the distance-dependent slope term is greater, presumably due to the large fault plane size.

Ghofrani, Hadi; Atkinson, Gail M.

2015-01-01

130

Duration of an Elastic Collision  

ERIC Educational Resources Information Center

With a pedagogical goal, this paper deals with a study of the duration of an elastic collision of an inflatable spherical ball on a planar surface suitable for undergraduate studies. First, the force generated by the deformed spherical ball is obtained under assumptions that are discussed. The study of the motion of the spherical ball colliding…

de Izarra, Charles

2012-01-01

131

Curricular internship Timing and Duration  

E-print Network

1 Art.1 Curricular internship Art.2 Objectives Art.3 Timing and Duration Art.4 Choice of Employer Art.5 Pertinence of the internship Art.6 Internship Search GRADUATE INTERNSHIP GUIDELINES Faculties training or work experience, herein referred to as `internship', is one of the graduation requirements. 2

Krause, Rolf

132

JACEE long duration balloon flights  

SciTech Connect

JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1--100{ital A} TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed.

Burnett, T.; Dake, S.; Derrickson, J.; Fountain, W.; Fuki, M.; Gregory, J.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W.V.; Jurak, A.; Lord, J.J.; Miyamura, O.; Oda, H.; Ogata, T.; Parnell, T.A.; Roberts, E.; Strausz, S.; Tabuki, T.; Takahashi, Y.; Tominaga, Y.; Watts, J.W.; Wefel, J.P.; Wilczynska, B.; Wilczynski, H.; Wilkes, R.J.; Wolter, W.; Wosiek, B. (ICR, Tokyo (Japan) Kobe Univ., Kobe (Japan) Osaka University, Osaka (Japan) Matsusho Gakuen Junior College, Matsumoto (Japan) NASA, Washington, DC (USA) University of Alabama at Huntsville, Huntsville, AL (USA) Louisiana State University, Baton Rouge, LA (USA) NASA/Marshall Space Flight Ctr., Huntsville, AL (USA) University of Washington, Seattle, WA (USA) INP, Krakow (Poland)); JACEE Collaboration

1990-01-15

133

Voice attractiveness: influence of stimulus duration and type.  

PubMed

Voice attractiveness is a relatively new area of research. Some aspects of the methodology used in this domain deserve particular attention. Especially, the duration of voice samples is often neglected as a factor and happens to be manipulated without the perceptual consequences of these manipulations being known. Moreover, the type of voice stimulus varies from a single vowel to complex sentences. The aim of this experiment was to investigate the extent to which stimulus duration (nonmanipulated vs. normalized) and type (vowel vs. word) influence perceived voice attractiveness. Twenty-seven male and female raters made attractiveness judgments of 30 male and female voice samples. Voice samples included a single vowel /a/, a three-vowel series /i a o/, and the French word "bonjour" (i.e., "hello"). These samples were presented in three conditions: nonmanipulated, shortened, and lengthened duration. Duration manipulation was performed using the pitch synchronous overlap and add (PSOLA) algorithm implemented in Praat. Results for the effect of stimulus type showed that word length samples were more attractive to the opposite sex than vowels. Results for the effect of duration showed that the nonmanipulated sound sample duration was not predictive of perceived attractiveness. Duration manipulation, on the other hand, altered perceived attractiveness for the lengthening condition. In particular, there was a linear decrease in attractiveness as a function of modification percentage (especially for the word, as compared with the vowels). Recommendations for voice sample normalization with the PSOLA algorithm are thus to prefer shortening over lengthening and, if not possible, to limit the extent of duration manipulation-for example, by normalizing to the mean sample duration. PMID:23239065

Ferdenzi, C; Patel, S; Mehu-Blantar, I; Khidasheli, M; Sander, D; Delplanque, S

2013-06-01

134

Business Cycle Duration Dependence: A Parametric Approach  

Microsoft Academic Search

This paper reexamines duration dependence in U.S. business cycles using parametric hazard models. Positive duration dependence would indicate that expansions or contractions are more likely to end as they become \\

Daniel E Sichel

1991-01-01

135

Performability Analysis of Guarded-Operation Duration: A Translation Approach for Reward Model Solutions  

E-print Network

, reduction of total performance degradation, duration of guarded operation, reward model solutions, modelPerformability Analysis of Guarded-Operation Duration: A Translation Approach for Reward Model-suited for application of reward model solution techniques. On the other hand, the complexity of performability

Illinois at Urbana-Champaign, University of

136

On the Duration of Civil War  

Microsoft Academic Search

We have modeled the duration of large-scale, violent civil conflicts, applying hazardfunctions to a comprehensive data set of such conflicts for the period 1960-99. We findthat the duration of conflicts is determined by a substantially different set of variablesfrom those which determine the initiation. The duration of conflict is substantiallyincreased if the society is composed of a few large ethnic

Paul Collier; Anke Hoeffler

1999-01-01

137

Office of Student Financial Aid Duration Appeal  

E-print Network

Office of Student Financial Aid Graduate Duration Appeal 0210 Beardshear Hall Ames, IA 50011-2028 515-294-2223 financialaid@iastate.edu SAP GRAD This appeal is for graduate students who have not met the Satisfactory Academic Progress (SAP) Duration of Eligibility requirements. The duration appeal and supporting

Lin, Zhiqun

138

Cohabitation Duration and Transient Domesticity  

PubMed Central

Research finds that many impoverished urban Black adults engage in a pattern of partnering and family formation involving a succession of short cohabitations yielding children, a paradigm referred to as transient domesticity. Researchers have identified socioeconomic status, cultural adaptations, and urbanicity as explanations for aspects of this pattern. We used longitudinal data from the 2001 Survey of Income and Program Participation to analyze variation in cohabitation and marriage duration by race/ethnicity, income, and urban residence. Proportional hazards regression indicated that separation risk is greater among couples that are cohabiting, below 200% of the federal poverty line, and Black but is not greater among urban dwellers. This provides empirical demographic evidence to support the emerging theory of transient domesticity and suggests that both socioeconomic status and race explain this pattern. We discuss the implications of these findings for understanding transient domesticity and make recommendations for using the Survey of Income and Program Participation to further study this family formation paradigm. PMID:24273358

GOLUB, ANDREW; REID, MEGAN; STRICKLER, JENNIFER; DUNLAP, ELOISE

2013-01-01

139

Prevalence and inter-relationship of different Doppler measures of dyssynchrony in patients with heart failure and prolonged QRS: a report from CARE-HF  

PubMed Central

Background Cardiac resynchronisation therapy (CRT) improves mortality and morbidity in heart failure patients with wide QRS. Observational studies suggest that patients having more left ventricular dyssynchrony pre-implantation obtain greater benefit on ventricular function and symptoms with CRT. Aim To provide an analysis of the prevalence and type of dyssynchrony in patients included in the CARE-HF trial. Methods 100 patients 67 (58 to 71) years were examined with echocardiography including tissue doppler imaging before receiving a CRT-pacemaker. Atrio-ventricular dyssynchrony (LVFT/RR) was defined as left ventricular filling time <40% of the RR-interval. Inter-ventricular mechanical delay (IVMD) was measured as the difference in onset of Doppler-flow in the pulmonary and aortic outflow tracts >40 ms. Intra-ventricular (regional) dyssynchrony in a 16-segment model was expressed either as a delayed longitudinal contraction (DLC) during the postsystolic phase or by tissue synchronisation imaging (TSI) with a predefined time-difference in systolic maximal velocities >85 ms. Results LVFT/RR was present in 34% and IVMD in 60% of patients while intra-ventricular dyssynchrony was present in 85% (DLC) and 86% (TSI) with a high agreement between the measures (Kappascore 0.86–1.00), indicating the methods being interchangeable. Patients with cardiomyopathy (53%) were more likely to have LVFT/RR <40% (45% vs. 21% (p= 0.02)) and more segments affected by intra-ventricular dyssynchrony 4(3, 5) vs. 3(1, 4), p = 0.002, compared to patients with ischemic heart disease. Conclusion The prevalence of intra-ventricular dyssynchrony is high in patients with heart failure, wide QRS and depressed systolic function. Most important, TSI appears to be a fast and reliable method to identify patients with intra-ventricular dyssynchrony likely to benefit from CRT. PMID:19128462

Edner, Magnus; Kim, Yong; Hansen, Knud Norregaard; Nissen, Henrik; Espersen, Geert; La Rosee, Karl; Maru, Fikru; Freemantle, Nick; Cleland, John; Sogaard, Peter

2009-01-01

140

Ischemic Ventricular Tachycardia Presenting as a Narrow Complex Tachycardia  

PubMed Central

This report describes a patient presenting with a narrow complex tachycardia in the context of prior myocardial infarction and impaired ventricular function. Electrophysiological studies confirmed ventricular tachycardia and activation and entrainment mapping demonstrated a critical isthmus within an area of scar involving the His-Purkinje system accounting for the narrow QRS morphology. This very rare case shares some similarities with upper septal ventricular tachycardia seen in patients with structurally normal hearts, but to our knowledge has not been seen previously in patients with ischemic heart disease. PMID:25057222

Page, Stephen P; Watts, Troy; Yeo, Wee Tiong; Mehul, Dhinoja

2014-01-01

141

Health care delivery system for long duration manned space operations  

NASA Technical Reports Server (NTRS)

Specific requirements for medical support of a long-duration manned facility in a low earth orbit derive from inflight medical experience, projected medical scenarios, mission related spacecraft and environmental hazards, health maintenance, and preventive medicine. A sequential buildup of medical capabilities tailored to increasing mission complexity is proposed. The space station health maintenance facility must provide preventive, diagnostic, and therapeutic medical support as immediate rescue capability may not exist.

Logan, J. S.; Shulman, E. L.; Johnson, P. C.

1983-01-01

142

Extended Duration Orbiter Medical Project  

NASA Technical Reports Server (NTRS)

Biomedical issues have presented a challenge to flight physicians, scientists, and engineers ever since the advent of high-speed, high-altitude airplane flight in the 1940s. In 1958, preparations began for the first manned space flights of Project Mercury. The medical data and flight experience gained through Mercury's six flights and the Gemini, Apollo, and Skylab projects, as well as subsequent space flights, comprised the knowledge base that was used to develop and implement the Extended Duration Orbiter Medical Project (EDOMP). The EDOMP yielded substantial amounts of data in six areas of space biomedical research. In addition, a significant amount of hardware was developed and tested under the EDOMP. This hardware was designed to improve data gathering capabilities and maintain crew physical fitness, while minimizing the overall impact to the microgravity environment. The biomedical findings as well as the hardware development results realized from the EDOMP have been important to the continuing success of extended Space Shuttle flights and have formed the basis for medical studies of crew members living for three to five months aboard the Russian space station, Mir. EDOMP data and hardware are also being used in preparation for the construction and habitation of International Space Station. All data sets were grouped to be non-attributable to individuals, and submitted to NASA s Life Sciences Data Archive.

Sawin, Charles F. (Editor); Taylor, Gerald R. (Editor); Smith, Wanda L. (Editor); Brown, J. Travis (Technical Monitor)

1999-01-01

143

NMDAR-dependent control of call duration in Xenopus laevis.  

PubMed

Many rhythmic behaviors, such as locomotion and vocalization, involve temporally dynamic patterns. How does the brain generate temporal complexity? Here, we use the vocal central pattern generator (CPG) of Xenopus laevis to address this question. Isolated brains can elicit fictive vocalizations, allowing us to study the CPG in vitro. The X. laevis advertisement call is temporally modulated; calls consist of rhythmic click trills that alternate between fast (approximately 60 Hz) and slow (approximately 30 Hz) rates. We investigated the role of two CPG nuclei--the laryngeal motor nucleus (n.IX-X) and the dorsal tegmental area of the medulla (DTAM)--in setting rhythm frequency and call durations. We discovered a local field potential wave in DTAM that coincides with fictive fast trills and phasic activity that coincides with fictive clicks. After disrupting n.IX-X connections, the wave persists, whereas phasic activity disappears. Wave duration was temperature dependent and correlated with fictive fast trills. This correlation persisted when wave duration was modified by temperature manipulations. Selectively cooling DTAM, but not n.IX-X, lengthened fictive call and fast trill durations, whereas cooling either nucleus decelerated the fictive click rate. The N-methyl-d-aspartate receptor (NMDAR) antagonist dAPV blocked waves and fictive fast trills, suggesting that the wave controls fast trill activation and, consequently, call duration. We conclude that two functionally distinct CPG circuits exist: 1) a pattern generator in DTAM that determines call duration and 2) a rhythm generator (spanning DTAM and n.IX-X) that determines click rates. The newly identified DTAM pattern generator provides an excellent model for understanding NDMAR-dependent rhythmic circuits. PMID:20393064

Zornik, Erik; Katzen, Abraham W; Rhodes, Heather J; Yamaguchi, Ayako

2010-06-01

144

NMDAR-Dependent Control of Call Duration in Xenopus laevis  

PubMed Central

Many rhythmic behaviors, such as locomotion and vocalization, involve temporally dynamic patterns. How does the brain generate temporal complexity? Here, we use the vocal central pattern generator (CPG) of Xenopus laevis to address this question. Isolated brains can elicit fictive vocalizations, allowing us to study the CPG in vitro. The X. laevis advertisement call is temporally modulated; calls consist of rhythmic click trills that alternate between fast (?60 Hz) and slow (?30 Hz) rates. We investigated the role of two CPG nuclei—the laryngeal motor nucleus (n.IX–X) and the dorsal tegmental area of the medulla (DTAM)—in setting rhythm frequency and call durations. We discovered a local field potential wave in DTAM that coincides with fictive fast trills and phasic activity that coincides with fictive clicks. After disrupting n.IX–X connections, the wave persists, whereas phasic activity disappears. Wave duration was temperature dependent and correlated with fictive fast trills. This correlation persisted when wave duration was modified by temperature manipulations. Selectively cooling DTAM, but not n.IX–X, lengthened fictive call and fast trill durations, whereas cooling either nucleus decelerated the fictive click rate. The N-methyl-d-aspartate receptor (NMDAR) antagonist dAPV blocked waves and fictive fast trills, suggesting that the wave controls fast trill activation and, consequently, call duration. We conclude that two functionally distinct CPG circuits exist: 1) a pattern generator in DTAM that determines call duration and 2) a rhythm generator (spanning DTAM and n.IX–X) that determines click rates. The newly identified DTAM pattern generator provides an excellent model for understanding NDMAR-dependent rhythmic circuits. PMID:20393064

Katzen, Abraham W.; Rhodes, Heather J.; Yamaguchi, Ayako

2010-01-01

145

Trends in electric utility load duration curves  

SciTech Connect

This report documents the development and analysis of annual and quarterly load duration curves for each of the 10 Federal regions. The report describes analyses performed to test for changes in load duration curve shapes over time. These analyses are intended to aid the electric utility analyses and modeling activities of the Energy Information Administration (EIA) by expanding the understanding of current and expected load duration curve shapes. 7 figs., 13 tabs.

Not Available

1984-12-01

146

Training for long duration space missions  

NASA Technical Reports Server (NTRS)

The successful completion of an extended duration manned mission to Mars will require renewed research effort in the areas of crew training and skill retention techniques. The current estimate of inflight transit time is about nine months each way, with a six month surface visit, an order of magnitude beyond previous U.S. space missions. Concerns arise when considering the level of skill retention required for highly critical, one time operations such as an emergency procedure or a Mars orbit injection. The factors responsible for the level of complex skill retention are reviewed, optimal ways of refreshing degraded skills are suggested, and a conceptual crew training design for a Mars mission is outlined. Currently proposed crew activities during a Mars mission were reviewed to identify the spectrum of skills which must be retained over a long time period. Skill retention literature was reviewed to identify those factors which must be considered in deciding when and which tasks need retraining. Task, training, and retention interval factors were identified. These factors were then interpreted in light of the current state of spaceflight and adaptive training systems.

Goldberg, Joseph H.

1987-01-01

147

Long Duration Exposure Facility (LDEF)  

NASA Technical Reports Server (NTRS)

The Long Duration Exposure Facility (LDEF) was designed by the Marshall Space Flight Center (MSFC) to test the performance of spacecraft materials, components, and systems that have been exposed to the environment of micrometeoroids and space debris for an extended period of time. The LDEF proved invaluable to the development of future spacecraft and the International Space Station (ISS). The LDEF carried 57 science and technology experiments, the work of more than 200 investigators. MSFC`s experiments included: Trapped Proton Energy Determination to determine protons trapped in the Earth's magnetic field and the impact of radiation particles; Linear Energy Transfer Spectrum Measurement Experiment which measures the linear energy transfer spectrum behind different shielding configurations; Atomic oxygen-Simulated Out-gassing, an experiment that exposes thermal control surfaces to atomic oxygen to measure the damaging out-gassed products; Thermal Control Surfaces Experiment to determine the effects of the near-Earth orbital environment and the shuttle induced environment on spacecraft thermal control surfaces; Transverse Flat-Plate Heat Pipe Experiment, to evaluate the zero-gravity performance of a number of transverse flat plate heat pipe modules and their ability to transport large quantities of heat; Solar Array Materials Passive LDEF Experiment to examine the effects of space on mechanical, electrical, and optical properties of lightweight solar array materials; and the Effects of Solar Radiation on Glasses. Launched aboard the Space Shuttle Orbiter Challenger's STS-41C mission April 6, 1984, the LDEF remained in orbit for five years until January 1990 when it was retrieved by the Space Shuttle Orbiter Columbia STS-32 mission and brought back to Earth for close examination and analysis.

1984-01-01

148

Correlates of Long Sleep Duration  

PubMed Central

Study Objective Sleeping more than 7 to 8 hours per day has been consistently associated with increased mortality. Whether this association is causal and what pathways explain this association are unknown. We sought to identify factors that could potentially explain the association between long sleep and mortality. Design Cross-sectional epidemiologic survey. Participants Middle-aged women (n = 60,028) participating in the Nurses Health Study II who reported a habitual sleep duration of 7 hours or more. Results Multiple sclerosis (odds ratio [OR] = 3.7, 95% confidence interval [3.0–4.5]), antidepressant use (OR = 3.1, [2.9–3.3]), benzodiazepine use (OR = 3.0 [2.6–3.3]), and systemic lupus erythematosus (OR = 2.9, [2.3–3.6]) were the factors most strongly associated with prolonged sleep. Combining these data with prevalence information and a range of plausible associations with mortality, the confounding rate ratio was estimated. This parameter is the ratio of the unadjusted long sleep–mortality rate ratio to the rate ratio adjusted for the factor and measures the extent that the factor can alter the long sleep—mortality association, either through confounding or as a causal intermediate. Based on this parameter, psychiatric and socioeconomic factors have the greatest potential to influence the long sleep–mortality relationship. Assuming each factor doubles mortality risk, the confounding rate ratios for depression, antidepressant use, and unemployment were 1.10, 1.18, and 1.12. Lesser influential factors were benzodiazepine use, poverty, low societal status, sedentary lifestyle, and obesity. Conclusion Depression and low socioeconomic status are strong candidates for producing the statistical association between long sleep and mortality, either as confounders or as causal intermediates. Future causal research on the effects of long sleep should include a detailed assessment of psychiatric disease and socioeconomic status. PMID:16895254

Patel, Sanjay R.; Malhotra, Atul; Gottlieb, Daniel J.; White, David P.; Hu, Frank B.

2012-01-01

149

Repair of Electronics for Long Duration Spaceflight  

NASA Technical Reports Server (NTRS)

To reduce mission risk, long duration spaceflight and exploration activities will require greater degrees of self-sufficiency with regards to repair capability than have ever been employed before in space exploration. The current repair paradigm of replacing Orbital Replacement Units (ORUs) of malfunctioning avionics and electronic hardware will be impractical, since carrying all of the spares that could possibly be needed for a long duration mission would require upmass and volume at unprecedented and unacceptable levels. A strategy of component-level repair for electronics, however, could significantly reduce the mass and volume necessary for spares and enhance mission safety via a generic contingency capability. This approach is already used to varying degrees by the U.S. Navy, where vessels at sea experience some similar constraints such as the need for self sufficiency for moderately long time periods, and restrictions on volume of repair spares and infrastructure. The concept of conducting component-level repairs of electronics in spacecraft requires the development of design guidelines for future avionics (to enable repair), development of diagnostic techniques to allow an astronaut to pinpoint the faulty component aboard a vastly complex vehicle, and development of tools and methodologies for dealing with the physical processes of replacing the component. This physical process includes tasks such as conformal coating removal and replacement, component removal, replacement, and alignment--all in the difficulty of a reduced gravity environment. Further, the gravitational effects on the soldering process must be characterized and accounted for to ensure reliability of the newly repaired components. The Component-Level Electronics-Assembly Repair (CLEAR) project under the NASA Supportability program was established to develop and demonstrate the practicality of this repair approach. CLEAR involves collaborative efforts between NASA s Glenn Research Center, Langley Research Center, Johnson Space Center, the National Center for Space Exploration Research, and the U.S. Navy. The project goals are 1) develop and demonstrate a manually-operated electronics repair capability to be conducted in a spacecraft environment; and 2) develop guidelines for designs of electronics that facilitates component-level repair for future space exploration efforts. This multi-faceted program utilizes a cross-disciplinary approach to examine pre- and post-repair diagnostics, conformal coating removal and replacement, component soldering, and electronics design for supportability. These areas are investigated by a combination of trade studies, ground based testing, reduced gravity aircraft testing, and actual spaceflight testing on the International Space Station (ISS) in multiple experiments. This paper details the efforts of this program, with emphasis on early trade study results, ground-based efforts, and two upcoming ISS experiments.

Pettegrew, Richard D.; Easton, John; Struk, Peter

2007-01-01

150

The neuroanatomical substrate of sound duration discrimination  

Microsoft Academic Search

We investigated the neuroanatomical substrate of sound duration discrimination, using the same experimental design as in a previous study on sound intensity discrimination [J. Neurosci. 18 (16) (1998) 6388]. Seven normal subjects were trained to detect deviant sounds presented with a slightly longer duration than a 300ms long standard harmonic sound, using a Go\\/No Go paradigm. Individual psychometric curves were

Pascal Belin; Stephen McAdams; Lionel Thivard; Bennett Smith; Sophie Savel; Monica Zilbovicius; Séverine Samson; Yves Samson

2002-01-01

151

Stimulus Intensity and the Perception of Duration  

Microsoft Academic Search

This article explores the widely reported finding that the subjective duration of a stimulus is positively related to its magnitude. In Experiments 1 and 2 we show that, for both auditory and visual stimuli, the effect of stimulus magnitude on the perception of duration depends upon the background: Against a high intensity background, weak stimuli are judged to last longer.

William J. Matthews; Neil Stewart; John H. Wearden

2011-01-01

152

Robust COA planning with varying durations  

Microsoft Academic Search

COA (Course of Action) planning involves resource allocation and task scheduling. Traditionally, this problem is tackled with the assumption that task duration is constant and with the objective to minimize the makespan. In contrast to this, this paper assumes task duration can vary in a time interval and the objective is to maximize the RM (Robustness Measure) given the deadline,

Luohao Tang; Cheng Zhu; Weiming Zhang; Zhong Liu

2011-01-01

153

Maternal age and duration of labor.  

PubMed

The computerized records of a population of 7214 women who were delivered during the period 1987-1991 were analysed. We studied the possible relationship of the duration of the first and second stages of labor to maternal age. In para 0, para 1 and para 2+ mothers we found an independent positive correlation between the second stage duration and maternal age. By multiple stepwise regression analysis maternal age turns out to be one of the most influential maternal characteristics of the second stage of labor. No correlation was found between maternal age and the duration of the first stage. PMID:8122504

Rasmussen, S; Bungum, L; Høie, K

1994-03-01

154

14 CFR 21.181 - Duration.  

Code of Federal Regulations, 2014 CFR

...issue or renewal unless the FAA prescribes a shorter period. The duration of an experimental certificate issued for operating amateur-built aircraft, exhibition, air-racing, operating primary kit-built aircraft, or operating light-sport...

2014-01-01

155

Duration of Anticoagulant Therapy After Venous Thromboembolism  

Microsoft Academic Search

\\u000a Long-term treatment of venous thromboembolism (VTE) primarily focuses on the duration of anticoagulant therapy, usually with\\u000a vitamin K antagonists (VKA). The duration of therapy should be individualized based on the risk of recurrent VTE if treatment\\u000a is stopped and the risk of bleeding if treatment is continued. The risk of recurrence is low if thrombosis was provoked by\\u000a a reversible

Clive Kearon

156

Strong motion duration and earthquake magnitude relationships  

SciTech Connect

Earthquake duration is the total time of ground shaking from the arrival of seismic waves until the return to ambient conditions. Much of this time is at relatively low shaking levels which have little effect on seismic structural response and on earthquake damage potential. As a result, a parameter termed ``strong motion duration`` has been defined by a number of investigators to be used for the purpose of evaluating seismic response and assessing the potential for structural damage due to earthquakes. This report presents methods for determining strong motion duration and a time history envelope function appropriate for various evaluation purposes, for earthquake magnitude and distance, and for site soil properties. There are numerous definitions of strong motion duration. For most of these definitions, empirical studies have been completed which relate duration to earthquake magnitude and distance and to site soil properties. Each of these definitions recognizes that only the portion of an earthquake record which has sufficiently high acceleration amplitude, energy content, or some other parameters significantly affects seismic response. Studies have been performed which indicate that the portion of an earthquake record in which the power (average rate of energy input) is maximum correlates most closely with potential damage to stiff nuclear power plant structures. Hence, this report will concentrate on energy based strong motion duration definitions.

Salmon, M.W.; Short, S.A. [EQE International, Inc., San Francisco, CA (United States); Kennedy, R.P. [RPK Structural Mechanics Consulting, Yorba Linda, CA (United States)

1992-06-01

157

Ongoing behavior predicts perceptual report of interval duration  

PubMed Central

The ability to estimate the passage of time is essential for adaptive behavior in complex environments. Yet, it is not known how the brain encodes time over the durations necessary to explain animal behavior. Under temporally structured reinforcement schedules, animals tend to develop temporally structured behavior, and interval timing has been suggested to be accomplished by learning sequences of behavioral states. If this is true, trial to trial fluctuations in behavioral sequences should be predictive of fluctuations in time estimation. We trained rodents in an duration categorization task while continuously monitoring their behavior with a high speed camera. Animals developed highly reproducible behavioral sequences during the interval being timed. Moreover, those sequences were often predictive of perceptual report from early in the trial, providing support to the idea that animals may use learned behavioral patterns to estimate the duration of time intervals. To better resolve the issue, we propose that continuous and simultaneous behavioral and neural monitoring will enable identification of neural activity related to time perception that is not explained by ongoing behavior. PMID:24672473

Gouvêa, Thiago S.; Monteiro, Tiago; Soares, Sofia; Atallah, Bassam V.; Paton, Joseph J.

2014-01-01

158

Microcontroller uses in Long-Duration Ballooning  

NASA Astrophysics Data System (ADS)

This paper discusses how microcontrollers are being utilized to fulfill the demands of long duration ballooning (LDB) and the advantages of doing so. The Columbia Scientific Balloon Facility (CSBF) offers the service of launching high altitude balloons (120k ft) which provide an over the horizon telemetry system and platform for scientific research payloads to collect data. CSBF has utilized microcontrollers to address multiple tasks and functions which were previously performed by more complex systems. A microcontroller system has been recently developed and programmed in house to replace our previous backup navigation system which is used on all LDB flights. A similar microcontroller system was developed to be independently launched in Antarctica before the actual scientific payload. This system's function is to transmit its GPS position and a small housekeeping packet so that we can confirm the upper level float winds are as predicted from satellite derived models. Microcontrollers have also been used to create test equipment to functionally check out the flight hardware used in our telemetry systems. One test system which was developed can be used to quickly determine if our communication link we are providing for the science payloads is functioning properly. Another system was developed to provide us with the ability to easily determine the status of one of our over the horizon communication links through a closed loop system. This test system has given us the capability to provide more field support to science groups than we were able to in years past. The trend of utilizing microcontrollers has taken place for a number of reasons. By using microcontrollers to fill these needs, it has given us the ability to quickly design and implement systems which meet flight critical needs, as well as perform many of the everyday tasks in LDB. This route has also allowed us to reduce the amount of time required for personnel to perform a number of the tasks required during the initial fabrication and also refurbishing processes of flight hardware systems. The recent use of microcontrollers in the design of both LDB flight hardware and test equipment has shown some examples of the adaptability and usefulness they have provided for our workplace.

Jones, Joseph

159

Sleep duration, cardiovascular disease, and proinflammatory biomarkers  

PubMed Central

Habitual sleep duration has been associated with cardiometabolic disease, via several mechanistic pathways, but few have been thoroughly explored. One hypothesis is that short and/or long sleep duration is associated with a proinflammatory state, which could increase risk for cardiovascular and metabolic diseases. This hypothesis has been largely explored in the context of experimental sleep deprivation studies which have attempted to demonstrate changes in proinflammatory markers following acute sleep loss in the laboratory. Despite the controlled environment available in these studies, samples tend to lack generalization to the population at large and acute sleep deprivation may not be a perfect analog for short sleep. To address these limitations, population based studies have explored associations between proinflammatory markers and habitual sleep duration. This review summarizes what is known from experimental and cross-sectional studies about the association between sleep duration, cardiovascular disease, and proinflammatory biomarkers. First, the association between sleep duration with both morbidity and mortality, with a focus on cardiovascular disease, is reviewed. Then, a brief review of the potential role of proinflammatory markers in cardiovascular disease is presented. The majority of this review details specific findings related to specific molecules, including tumor necrosis factor-?, interleukins-1, -6, and -17, C-reactive protein, coagulation molecules, cellular adhesion molecules, and visfatin. Finally, a discussion of the limitations of current studies and future directions is provided. PMID:23901303

Grandner, Michael A; Sands-Lincoln, Megan R; Pak, Victoria M; Garland, Sheila N

2013-01-01

160

Duration of immunity to norovirus gastroenteritis.  

PubMed

The duration of immunity to norovirus (NoV) gastroenteritis has been believed to be from 6 months to 2 years. However, several observations are inconsistent with this short period. To gain better estimates of the duration of immunity to NoV, we developed a mathematical model of community NoV transmission. The model was parameterized from the literature and also fit to age-specific incidence data from England and Wales by using maximum likelihood. We developed several scenarios to determine the effect of unknowns regarding transmission and immunity on estimates of the duration of immunity. In the various models, duration of immunity to NoV gastroenteritis was estimated at 4.1 (95% CI 3.2-5.1) to 8.7 (95% CI 6.8-11.3) years. Moreover, we calculated that children (<5 years) are much more infectious than older children and adults. If a vaccine can achieve protection for duration of natural immunity indicated by our results, its potential health and economic benefits could be substantial. PMID:23876612

Simmons, Kirsten; Gambhir, Manoj; Leon, Juan; Lopman, Ben

2013-08-01

161

Estimating magnitude and duration of incident delays  

SciTech Connect

Traffic congestion is a major operational problem on urban freeways. In the case of recurring congestion, travelers can plan their trips according to the expected occurrence and severity of recurring congestion. However, nonrecurring congestion cannot be managed without real-time prediction. Evaluating the efficiency of intelligent transportation systems (ITS) technologies in reducing incident effects requires developing models that can accurately predict incident duration along with the magnitude of nonrecurring congestion. This paper provides two statistical models for estimating incident delay and a model for predicting incident duration. The incident delay models showed that up to 85% of variation in incident delay can be explained by incident duration, number of lanes affected, number of vehicles involved, and traffic demand before the incident. The incident duration prediction model showed that 81% of variation in incident duration can be predicted by number of lanes affected, number of vehicles involved, truck involvement, time of day, police response time, and weather condition. These findings have implications for on-line applications within the context of advanced traveler information systems (ATIS).

Garib, A. [Zagazig Univ. (Egypt). Construction Engineering Dept.; Radwan, A.E.; Al-Deek, H. [Univ. of Central Florida, Orlando, FL (United States). Dept. of Civil and Environmental Engineering

1997-11-01

162

20 CFR 336.3 - Duration of normal sickness benefits.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Duration of normal sickness benefits. 336.3 Section 336.3...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal...

2011-04-01

163

20 CFR 336.2 - Duration of normal unemployment benefits.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2012-04-01 true Duration of normal unemployment benefits. 336.2 Section 336...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal...

2013-04-01

164

20 CFR 336.2 - Duration of normal unemployment benefits.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2012-04-01 true Duration of normal unemployment benefits. 336.2 Section 336...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal...

2014-04-01

165

20 CFR 336.2 - Duration of normal unemployment benefits.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Duration of normal unemployment benefits. 336.2 Section 336...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal...

2011-04-01

166

20 CFR 336.3 - Duration of normal sickness benefits.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2012-04-01 true Duration of normal sickness benefits. 336.3 Section 336.3...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal...

2013-04-01

167

20 CFR 336.2 - Duration of normal unemployment benefits.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Duration of normal unemployment benefits. 336.2 Section 336...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal...

2012-04-01

168

20 CFR 336.3 - Duration of normal sickness benefits.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Duration of normal sickness benefits. 336.3 Section 336.3...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal...

2010-04-01

169

20 CFR 336.3 - Duration of normal sickness benefits.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Duration of normal sickness benefits. 336.3 Section 336.3...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal...

2012-04-01

170

20 CFR 336.3 - Duration of normal sickness benefits.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2012-04-01 true Duration of normal sickness benefits. 336.3 Section 336.3...RAILROAD UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal...

2014-04-01

171

Effect of Bolus Volume and Consistency on Swallowing Events Duration in Healthy Subjects  

PubMed Central

Background/Aims Swallowing is a complex function with the control of the swallowing center being located in the brain stem. Our aim in this investigation was to evaluate, in healthy volunteers, the oral and pharyngeal transit of 2 bolus volumes and 2 consistencies, and the influence of these boluses on the proportion of pharyngeal clearance duration/hyoid movement duration. Methods Videofluoroscopic evaluation of swallows was performed in 30 healthy volunteers, aged 29–77 years (mean 58 years). The subjects swallowed in duplicate of 5 mL and 10 mL of thick liquid barium and honey thick barium. We measured the duration of oral transit, pharyngeal transit, pharyngeal clearance, upper esophageal sphincter opening, hyoid movement, oropharyngeal transit, and the relation pharyngeal clearance duration/hyoid movement duration. Results A 10 mL bolus volume caused a longer UES opening duration than a 5 mL bolus volume, for both consistencies. The pharyngeal transit was longer for honey thick bolus consistency than for thick liquid, with both the volumes of 5 mL and 10 mL. For pharyngeal clearance, the difference was significant only with the 10 mL bolus volume. There was no difference associated with bolus volume or consistency in the relation between pharyngeal clearance duration and hyoid movement duration. Conclusions Increase in the swallowed bolus volume causes a longer UES opening duration and an increase in bolus consistency from thick liquid to honey thick causes a longer pharyngeal transit duration. The proportion between pharyngeal clearance and hyoid movement does not change with bolus volume or bolus consistency. PMID:25540944

Nascimento, Weslania V; Cassiani, Rachel A; Santos, Carla M; Dantas, Roberto O

2015-01-01

172

STS mission duration enhancement study: (orbiter habitability)  

NASA Technical Reports Server (NTRS)

Habitability improvements for early flights that could be implemented with minimum impact were investigated. These included: (1) launching the water dispenser in the on-orbit position instead of in a locker; (2) the sleep pallet concept; and (3) suction cup foot restraints. Past studies that used volumetric terms and requirements for crew size versus mission duration were reviewed and common definitions of key habitability terms were established. An accurately dimensioned drawing of the orbiter mid-deck, locating all of the known major elements was developed. Finally, it was established that orbiter duration and crew size can be increased with minimum modification and impact to the crew module. Preliminary concepts of the aft med-deck, external versions of expanded tunnel adapters (ETA), and interior concepts of ETA-3 were developed and comparison charts showing the various factors of volume, weight, duration, size, impact to orbiter, and number of sleep stations were generated.

Carlson, A. D.

1979-01-01

173

Thermoresponsive nanogels for prolonged duration local anesthesia  

PubMed Central

Nanogels based on poly(N-isopropylacrylamide) are attractive vehicles for prolonged duration local anesthesia because of their tunable size, number of functional groups, thermoresponsiveness, and their anionic charge. Nerve block durations of up to nine hours were achieved using acrylic acid-loaded nanogels loaded with bupivacaine. Increasing the anionic charge density of the nanogels or (for more highly acid-functionalized nanogels) decreasing the nanogel size facilitated longer duration anesthetic release. Small (<300 nm diameter) nanogels formed dense aggregates upon injection in vivo and induced only mild inflammatory responses, while large (>500 nm diameter) nanogels typically remained as liquid-like residues in vivo and induced more severe inflammatory reactions. PMID:22732383

Hoare, Todd; Young, Stuart; Lawlor, Michael W.; Kohane, Daniel S.

2012-01-01

174

Thermoresponsive nanogels for prolonged duration local anesthesia.  

PubMed

Nanogels based on poly(N-isopropylacrylamide) are attractive vehicles for prolonged duration local anesthesia because of their tunable size, number of functional groups, thermoresponsiveness and anionic charge. Nerve block durations of up to 9h were achieved using acrylic acid-loaded nanogels loaded with bupivacaine. Increasing the anionic charge density of the nanogels or (for more highly acid-functionalized nanogels) decreasing the nanogel size facilitated longer duration of anesthetic release. Small (<300 nm diameter) nanogels formed dense aggregates upon injection in vivo and induced only mild inflammatory responses, while large (>500 nm diameter) nanogels typically remained as liquid-like residues in vivo and induced more severe inflammatory reactions. PMID:22732383

Hoare, Todd; Young, Stuart; Lawlor, Michael W; Kohane, Daniel S

2012-10-01

175

Slow Wave Sleep and Long Duration Spaceflight  

NASA Technical Reports Server (NTRS)

While ground research has clearly shown that preserving adequate quantities of sleep is essential for optimal health and performance, changes in the progression, order and /or duration of specific stages of sleep is also associated with deleterious outcomes. As seen in Figure 1, in healthy individuals, REM and Non-REM sleep alternate cyclically, with stages of Non-REM sleep structured chronologically. In the early parts of the night, for instance, Non-REM stages 3 and 4 (Slow Wave Sleep, or SWS) last longer while REM sleep spans shorter; as night progresses, the length of SWS is reduced as REM sleep lengthens. This process allows for SWS to establish precedence , with increases in SWS seen when recovering from sleep deprivation. SWS is indeed regarded as the most restorative portion of sleep. During SWS, physiological activities such as hormone secretion, muscle recovery, and immune responses are underway, while neurological processes required for long term learning and memory consolidation, also occur. The structure and duration of specific sleep stages may vary independent of total sleep duration, and changes in the structure and duration have been shown to be associated with deleterious outcomes. Individuals with narcolepsy enter sleep through REM as opposed to stage 1 of NREM. Disrupting slow wave sleep for several consecutive nights without reducing total sleep duration or sleep efficiency is associated with decreased pain threshold, increased discomfort, fatigue, and the inflammatory flare response in skin. Depression has been shown to be associated with a reduction of slow wave sleep and increased REM sleep. Given research that shows deleterious outcomes are associated with changes in sleep structure, it is essential to characterize and mitigate not only total sleep duration, but also changes in sleep stages.

Whitmire, Alexandra; Orr, Martin; Arias, Diana; Rueger, Melanie; Johnston, Smith; Leveton, Lauren

2012-01-01

176

The Burst Time Duration in Micropillar Deformation  

NASA Astrophysics Data System (ADS)

Plastic flow of single crystal micropillars proceeds through a sequence of intermittent burst slips. The burst time durations are investigated based on an extended theoretical model which incorporates the observed power-law distribution of burst sizes in compression experiments of micropillars. The results show that the burst time durations exhibit a powerlaw behavior with an exponential cutoff, suggesting the same scaling behaviors as the burst sizes. In addition, the predicted scaling exponent is found to converge to a value of ~1.6. It is demonstrated that our results are consistent with the experimental data.

Zhang, Xu; Shang, Fu-Lin

2014-02-01

177

Slow Wave Sleep and Long Duration Spaceflight  

NASA Technical Reports Server (NTRS)

To review the literature on slow wave sleep (SWS) in long duration space flight, and place this within the context of the broader literature on SWS particularly with respect to analogous environments such as the Antarctic. Explore how SWS could be measured within the International Space Station (ISS) context with the aim to utilize the ISS as an analog for future extra-orbital long duration missions. Discuss the potential use of emergent minimally intrusive wireless technologies like ZEO for integrated prelaunch, flight, and return to Earth analysis and optimization of SWS (and general quality of sleep).

Orr, M.; Whitmire, A.; Arias, D.; Leveton, L.

2011-01-01

178

Effect of Second-Phase Duration on the Strength-Duration Relation for Human Transvenous Defibrillation  

Microsoft Academic Search

Background—The mechanism by which biphasic waveforms improve defibrillation efficacy is unclear. In addition, the optimal shape of the biphasic waveforms remains controversial. Animal experiments suggest that prolonging the duration of the second phase longer than the first worsens defibrillation thresholds (DFT). The purpose of this study was to determine the strength-duration relation for the second phase of a biphasic defibrillation

Stephen R. Shorofsky; Michael R. Gold

179

Effects of the shock duration on the response of CFRP composite laminates  

NASA Astrophysics Data System (ADS)

Shock loads induce a local tensile stress within a sample. The location and amplitude of this high strain rate stress can be monitored respectively by the duration and intensity of the shock. The process is applied to carbon fibre reinforced polymer (CFRP) composites, involved in aeronautic or defense industry. This paper describes the response of CFRP laminates of different thicknesses to a shock load normal to the fibres direction. The effects of the shock duration on the wave propagation are key issues of this work. Experiments have been performed on high power laser facilities and on a high power pulsed generator to get a wide range of pulse duration from fs to µs. Numerical simulation provides a comprehensive approach of the wave propagation and tensile stress generation within these complex materials. The main result concerns the relation between the load duration, the tensile stress and the induced delamination within 1, 4 and 8 ply composite laminates.

Gay, Elise; Berthe, Laurent; Boustie, Michel; Arrigoni, Michel; Buzaud, Eric

2014-11-01

180

Iterated rippled noise discrimination at long durations  

PubMed Central

Iterated rippled noise (IRN) was used to study discrimination of IRN stimuli with a lower number of iterations from IRN stimuli with a higher number of iterations as a function of stimulus duration (100–2000 ms). Such IRN stimuli differ in the strength of the repetition pitch. In some cases, the gain used to generate IRN stimuli was adjusted so that both IRN stimuli in the discrimination task had the same height of the first peak in the autocorrelation function or autocorrelogram. In previous work involving short-duration IRN stimuli (<500 ms), listeners were not able to discriminate between IRN stimuli that had different numbers of iterations but the same height of the first peak in the autocorrelation function. In the current study, IRN discrimination performance improved with increases in duration, even in cases when the height of the first peak in the autocorrelation was the same for the two IRN stimuli. Thus, future studies involving discrimination of IRN stimuli may need to use longer durations (1 s or greater) than those that have been used in the past. PMID:19739747

Yost, William A.

2009-01-01

181

Calculating Stage Duration Statistics in Multistage Diseases  

Microsoft Academic Search

Many human diseases are characterized by multiple stages of progression. While the typical sequence of disease progression can be identified, there may be large individual variations among patients. Identifying mean stage durations and their variations is critical for statistical hypothesis testing needed to determine if treatment is having a significant effect on the progression, or if a new therapy is

Natalia L. Komarova; Craig J. Thalhauser

2011-01-01

182

Short-Duration Simulations from Measurements.  

SciTech Connect

A method is presented that ascribes proper statistical variability to simulations that are derived from longer-duration measurements. This method is applicable to simulations of either real-value or integer-value data. An example is presented that demonstrates the applicability of this technique to the synthesis of gamma-ray spectra.

Mitchell, Dean J.; Enghauser, Michael

2014-08-01

183

Perception of duration in the parvocellular system  

PubMed Central

Both theoretical and experimental evidence suggests that duration perception is mediated preferentially by the color-blind but high temporally sensitive luminance pathway. In this experiment we tested whether color modulated stimuli and high spatial frequency luminance modulated stimuli, which are known to be relayed mostly by the slow parvocellular system, are able to elicit reliable sense of duration. We show that ramped color modulated stimuli seem to last less than luminance modulated stimuli matched for visibility. The effect is large, about 200 ms and is constant at all durations tested (range 500–1100 ms). However, high spatial frequency luminance stimuli obtain duration matches similar to those of low spatial frequency luminance modulated stimuli. The results at various levels of contrast and temporal smoothing indicate that equiluminant stimuli have higher contrast thresholds to activate the mechanisms which time visual stimuli. Overall the results imply that both the magnocellular and the parvocellular systems access reliably the timing mechanisms with a difference only in the way these are engaged. PMID:22470323

Cicchini, Guido M.

2012-01-01

184

Electrocorticogram encoding of upper extremity movement duration.  

PubMed

Electrocorticogram (ECoG) is a promising long-term signal acquisition platform for brain-computer interface (BCI) systems such as upper extremity prostheses. Several studies have demonstrated decoding of arm and finger trajectories from ECoG high-gamma band (80-160 Hz) signals. In this study, we systematically vary the velocity of three elementary movement types (pincer grasp, elbow and shoulder flexion/extension) to test whether the high-gamma band encodes for the entirety of the movements, or merely the movement onset. To this end, linear regression models were created for the durations and amplitudes of high-gamma power bursts and velocity deflections. One subject with 8×8 high-density ECoG grid (4 mm center-to-center electrode spacing) participated in the experiment. The results of the regression models indicated that the power burst durations varied directly with the movement durations (e.g. R(2)=0.71 and slope=1.0 s/s for elbow). The persistence of power bursts for the duration of the movement suggests that the primary motor cortex (M1) is likely active for the entire duration of a movement, instead of providing a marker for the movement onset. On the other hand, the amplitudes were less co-varied. Furthermore, the electrodes of maximum R(2) conformed to somatotopic arrangement of the brain. Also, electrodes responsible for flexion and extension movements could be resolved on the high-density grid. In summary, these findings suggest that M1 may be directly responsible for activating the individual muscle motor units, and future BCI may be able to utilize them for better control of prostheses. PMID:25570190

Wang, Po T; King, Christine E; McCrimmon, Colin M; Shaw, Susan J; Millett, David E; Liu, Charles Y; Chui, Luis A; Nenadic, Zoran; Do, An H

2014-08-01

185

NASA Long Duration Balloon capability development project  

NASA Technical Reports Server (NTRS)

A NASA development program is described for establishing near-global long-duration balloon (LDB) capabilities for both Antarctic and midlatitude applications. The program is intended to evaluate, research, and develop the balloon structures and systems needed for scientific payloads of over 1500 lbs for periods of up to three weeks. The systems examined include: control functions, data processing, power, navigation/positioning, and telecommunications. Test flights of the LDB Development Project in Antarctica are reported in which a 28 million cu ft balloon was launched with 3611 lbs of suspended weight. The subsystems under development are reported to work effectively for the test flights. Planned flights for the LDB based on these developments include gamma-ray and X-ray campaigns, a long-duration test in Antarctica, and an experiment based on magnetic passive isotopes.

Stuchlik, D.; Craddock, W.

1993-01-01

186

Duration Properties over Real Time System Designs  

Microsoft Academic Search

Constraints on the accumulated sojourn time at particular system states are among the possible requirements for a real-time system. These requirements are called duration properties. The need to predict temporal behavior of critical real-time systems has encouraged the development of a useful collection of results for run-time scheduling as well as an interesting set of formal automatic techniques based on

Víctor A. Braberman; Fabio Pieniazek

2000-01-01

187

Induced abortion and subsequent pregnancy duration  

Microsoft Academic Search

Objective: To examine whether induced abortion influences subsequent pregnancy duration.Methods: Women who had their first pregnancies during 1980, 1981, and 1982 were identified in three Danish national registries. A total of 15,727 women whose pregnancies were terminated by first-trimester induced abortions were compared with 46,026 whose pregnancies were not terminated by induced abortions. All subsequent pregnancies until 1994 were identified

Weijin Zhou; Henrik Toft Sørensen; Jørn Olsen

1999-01-01

188

The Duration of Labor in Healthy Women  

Microsoft Academic Search

OBJECTIVE:To measure the duration of active labor (first and second stages) in low-risk women whom received intrapartum care from certified nurse-midwives in nine hospital settings in the United States in 1996. Clinical factors and morbidity indicators associated with longer labors were also examined.DESIGN:An observational study was conducted with healthy women at term who did not receive oxytocin or epidurals (n

Leah L Albers; Leah L. Albers CNM DrPH

1999-01-01

189

F-wave-duration in diabetic polyneuropathy.  

PubMed

The diagnostic sensitivity of F-wave duration (Fdur) in diabetic polyneuropathy was analyzed. Some patients had abnormal Fdur values with normal minimum F latencies (Fmin). The incidence of abnormality for tibial and peroneal Fdur was somewhat more common than for Fmin in cases of suspected mild or early phase polyneuropathy. Fdur may provide additional diagnostic information in certain cases, particularly those in which there is mild polyneuropathy. PMID:9466603

Toyokura, M

1998-02-01

190

Evaluation of Long Duration Flight on Venus  

NASA Technical Reports Server (NTRS)

An analysis was performed to evaluate the potential of utilizing either an airship or aircraft as a flight platform for long duration flight within the atmosphere of Venus. In order to achieve long-duration flight, the power system for the vehicle had to be capable of operating for extended periods of time. To accomplish these, two types of power systems were considered, a solar energy-based power system utilizing a photovoltaic array as the main power source and a radioisotope heat source power system utilizing a Stirling engine as the heat conversion device. Both types of vehicles and power systems were analyzed to determine their flight altitude range. This analysis was performed for a station-keeping mission where the vehicle had to maintain a flight over a location on the ground. This requires the vehicle to be capable of flying faster than the wind speed at a particular altitude. An analysis was also performed to evaluate the altitude range and maximum duration for a vehicle that was not required to maintain station over a specified location. The results of the analysis show that each type of flight vehicle and power system was capable of flight within certain portions of Venus s atmosphere. The aircraft, both solar and radioisotope power proved to be the most versatile and provided the greatest range of coverage both for station-keeping and non-station-keeping missions.

Landis, Geoffrey A.; Colozza, Anthony J.

2006-01-01

191

ON THE DURATION OF BLAZAR SYNCHROTRON FLARES  

SciTech Connect

A semi-analytical model is presented that describes the temporal development of a blazar synchrotron flare for the case of a broadband synchrotron power spectrum. We examine three different injection scenarios and present its influence on the synchrotron flare. An accurate approximation of the half-life of a synchrotron flare is analytically computed and we give some illustrative examples of the time evolution of the emergent synchrotron intensity by using a numerical integration method. The synchrotron flare starts at all photon energies right after the injection of ultrarelativistic electrons into the spherical emission volume of radius R and its duration exceeds the light travel time 2R/c in the low energy regime. Furthermore, the flare duration extends by the period of injection of relativistic electrons into the emission knot. However, the energetic and spatial distribution of these injected electrons has no significant influence on the flare duration. We obtain a temporal behavior that agrees most favorably with the observations of PKS 2155-304 on 2006 July 29-30 and it differs considerably from the results that were recently achieved by using a monochromatic approximation of the synchrotron power.

Eichmann, B.; Schlickeiser, R. [Institut fuer Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universitaet Bochum, 44780 Bochum (Germany); Rhode, W. [Experimentelle Physik V, Technische Universitaet Dortmund, 44221 Dortmund (Germany)

2012-01-10

192

Antenatal breastfeeding education for increasing breastfeeding duration  

PubMed Central

Background Breastfeeding (BF) is well recognised as the best food for infants. The impact of antenatal BF education on the duration of BF has not been evaluated. Objectives To evaluate the effectiveness of antenatal BF education for increasing BF initiation and duration. Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (21 April 2010), CENTRAL (The Cochrane Library 2010, Issue 2), MEDLINE (1966 to April 2010) and SCOPUS (January 1985 to April 2010). We contacted experts and searched reference lists of retrieved articles. We updated the search of the Pregnancy and Childbirth Group’s Trials Register on 28 September 2011 and added the results to the awaiting classification section of the review. Selection criteria All identified published, unpublished and ongoing randomised controlled trials (RCTs) assessing the effect of formal antenatal BF education or comparing two different methods of formal antenatal BF education, on duration of BF. We excluded RCTs that also included intrapartum or postpartum BF education. Data collection and analysis We assessed all potential studies identified as a result of the search strategy. Two review authors extracted data from each included study using the agreed form and assessed risk of bias. We resolved discrepancies through discussion. Main results We included 17 studies with 7131 women in the review and 14 studies involving 6932 women contributed data to the analyses. We did not do any meta-analysis because there was only one study for each comparison. Five studies compared a single method of BF education with routine care. Peer counselling significantly increased BF initiation. Three studies compared one form of BF education versus another. No intervention was significantly more effective than another intervention in increasing initiation or duration of BF. Seven studies compared multiple methods versus a single method of BF education. Combined BF educational interventions were not significantly better than a single intervention in initiating or increasing BF duration. However, in one trial a combined BF education significantly reduced nipple pain and trauma. One study compared different combinations of interventions. There was a marginally significant increase in exclusive BF at six months in women receiving a booklet plus video plus lactation consultation (LC) compared with the booklet plus video only. Two studies compared multiple methods of BF education versus routine care. The combination of BF booklet plus video plus LC was significantly better than routine care for exclusive BF at three months. Authors’ conclusions Because there were significant methodological limitations and the observed effect sizes were small, it is not appropriate to recommend any antenatal BF education. There is an urgent need to conduct RCTs study with adequate power to evaluate the effectiveness of antenatal BF education. PMID:22071830

Lumbiganon, Pisake; Martis, Ruth; Laopaiboon, Malinee; Festin, Mario R; Ho, Jacqueline J; Hakimi, Mohammad

2014-01-01

193

Sleep duration and incidence of lung cancer in ageing men  

PubMed Central

Background Previous studies have suggested an association between sleep duration and cancer. However, the information on sleep duration regard to risk of lung cancer is scanty. Methods Analysed data comprised prospective population-based cohort of 2586 men (aged 42–60 years) from Eastern Finland. Baseline survey and clinical examinations took place 1984–1989, and diagnosed lung cancers were obtained until the end of 2011 through linkage with the Finnish Cancer Registry. Self-reported sleep was categorized as ?6.5 h, 7–7.5 h, and ?8 h. Subjects with prior history of cancer or psychotropic medication (hypnotics or sedatives) were excluded from the analyses. Cox proportional hazards models with adjustments for possible confounders were used to examine the association. Results Significant association between sleep duration and increased lung cancer risk was observed after adjustments for age, examination years, cumulative smoking history, family cancer history and Human Population Laboratory Depression scale scores (HR 2.12, 95% CI 1.17-3.85 for ?6.5 h sleep, and HR 1.88, 95% CI 1.09-3.22 for ?8 h sleep). Associations were even stronger among current smokers (HR 2.23, 95% CI 1.14-4.34 for ?6.5 h sleep, and HR 2.09, 95% CI 1.14-3.81 for ?8 h sleep). After further adjustments for alcohol consumption, physical activity, body mass index, marital status, education years, night work, employment status, asthma and chronic bronchitis, the association remained significant both in the whole study population and among smokers. When cumulative smoking history was replaced by current smoking in the adjustments, the increased risk was limited to those who slept <6.5 h. Conclusions Sleep duration of less than 7–7.5 hours or more than 7–7.5 hours associates with increased lung cancer risk. The physiological factors underlying the association are complex, and they may relate to melatonin excretion patterns, low-grade inflammation in cancer development process or disruptions in circadian rhythmicity. PMID:24684747

2014-01-01

194

The Particle Puzzle - Duration: 5:18.  

NASA Video Gallery

This video explores the complexity of atmospheric aerosols: how they impact climate and how researchers study them. Glory's Aerosol Polarimetry Sensor and Cloud Camera will provide an unprecedented...

195

Duration of rural training during residency  

PubMed Central

OBJECTIVE To determine whether rural family physicians thought they had received enough months of rural exposure during family medicine residency, how many months of rural exposure those who were satisfied with their training had had, and how many months of rural exposure those who were not satisfied with their training wanted. DESIGN Mailed survey. SETTING Rural Canada. PARTICIPANTS Rural family physicians who had graduated between 1991 and 2000 from a Canadian medical school. MAIN OUTCOME MEASURES Respondents’ opinions about whether their exposure to rural medicine during training had been adequate. RESULTS Response rate was 59% (382/651). After excluding physicians who had not had Canadian family medicine residency training, 348 physicians remained, and of those, 58% thought they had had adequate rural exposure during residency. Median duration of rural training among those who thought they had had enough rural exposure was 6 months; median duration of rural exposure among those who thought they had not had enough was 2 months. Median duration of rural exposure desired by those who thought they had not had enough rural training was 6 months. Some physicians wanted much more than 6 months of rural training; for example, one quarter of those satisfied with their rural training had had 10 or more months of rural rotations. Fewer than 1% of respondents thought they had received too much rural training. There was no significant difference in number of months of rural training preferred by men and women (P?=?.94). One third of respondents had graduated from rural-focused family practice residency programs. Rural program graduates were more likely than non–rural program graduates to report that the duration of their rural training was adequate (84% vs 46%, P?

Chan, Benjamin T.B.; Degani, Naushaba; Crichton, Tom; Pong, Raymond W.; Rourke, James T.; Goertzen, James; McCready, Bill

2006-01-01

196

Training Concept for Long Duration Space Mission  

NASA Technical Reports Server (NTRS)

There has been papers about maintenance and psychological training for Long Duration Space Mission (LDSM). There are papers on the technology needed for LDSMs. Few are looking at how groundbased pre-mission training and on-board in-transit training must be melded into one training concept that leverages this technology. Even more importantly, fewer are looking at how we can certify crews pre-mission. This certification must ensure, before the crew launches, that they can handle any problem using on-board assets without a large ground support team.

O'Keefe, William

2008-01-01

197

5 CFR 831.642 - Marriage duration requirements.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Marriage duration requirements. 831.642...Annuities Eligibility § 831.642 Marriage duration requirements. ...or (2) A child was born of the marriage, as explained in paragraph (c)...

2010-01-01

198

5 CFR 831.642 - Marriage duration requirements.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Marriage duration requirements. 831.642...Annuities Eligibility § 831.642 Marriage duration requirements. ...or (2) A child was born of the marriage, as explained in paragraph (c)...

2014-01-01

199

5 CFR 831.642 - Marriage duration requirements.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Marriage duration requirements. 831.642...Annuities Eligibility § 831.642 Marriage duration requirements. ...or (2) A child was born of the marriage, as explained in paragraph (c)...

2011-01-01

200

5 CFR 831.642 - Marriage duration requirements.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Marriage duration requirements. 831.642...Annuities Eligibility § 831.642 Marriage duration requirements. ...or (2) A child was born of the marriage, as explained in paragraph (c)...

2013-01-01

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5 CFR 831.642 - Marriage duration requirements.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Marriage duration requirements. 831.642...Annuities Eligibility § 831.642 Marriage duration requirements. ...or (2) A child was born of the marriage, as explained in paragraph (c)...

2012-01-01

202

49 CFR 385.117 - Duration of safety monitoring system.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Duration of safety monitoring system. 385.117 Section...SAFETY FITNESS PROCEDURES Safety Monitoring System for Mexico-Domiciled...385.117 Duration of safety monitoring system. (a) Each...

2011-10-01

203

14 CFR 47.41 - Duration and return of Certificate.  

Code of Federal Regulations, 2010 CFR

... false Duration and return of Certificate. 47.41 Section 47.41 ...AIRCRAFT AIRCRAFT REGISTRATION Certificates of Aircraft Registration § 47.41 Duration and return of Certificate. (a) Each Certificate...

2010-01-01

204

46 CFR 91.60-40 - Duration of Convention certificates.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Duration of Convention certificates. 91.60-40 Section 91.60-40...VESSELS INSPECTION AND CERTIFICATION Certificates Under International Convention for...60-40 Duration of Convention certificates. (a) The following...

2010-10-01

205

46 CFR 189.60-40 - Duration of Convention certificates.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Duration of Convention certificates. 189.60-40 Section 189.60-40...VESSELS INSPECTION AND CERTIFICATION Certificates Under International Convention for...60-40 Duration of Convention certificates. (a) The following...

2010-10-01

206

Time perception: paradigms, methods, target duration and individual differences   

E-print Network

The present study assessed the role of the time judgement paradigms of prospective and retrospective durations, the length of durations and the effects of the states of mood and arousal in time perception. The role of ...

McFarlane, Henriett A

2008-06-27

207

19 CFR 141.34 - Duration of power of attorney.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Duration of power of attorney. 141.34 Section 141.34...TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power of attorney. Powers of attorney...

2011-04-01

208

19 CFR 141.34 - Duration of power of attorney.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Duration of power of attorney. 141.34 Section 141.34...TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power of attorney. Powers of attorney...

2014-04-01

209

19 CFR 141.34 - Duration of power of attorney.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Duration of power of attorney. 141.34 Section 141.34...TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power of attorney. Powers of attorney...

2010-04-01

210

19 CFR 141.34 - Duration of power of attorney.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Duration of power of attorney. 141.34 Section 141.34...TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power of attorney. Powers of attorney...

2012-04-01

211

12 CFR 367.17 - Duration of suspensions and exclusions.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Duration of suspensions and exclusions. 367.17 Section...REGULATIONS AND STATEMENTS OF GENERAL POLICY SUSPENSION AND EXCLUSION OF CONTRACTOR AND TERMINATION...CONTRACTS § 367.17 Duration of suspensions and exclusions. (a)...

2010-01-01

212

7 CFR 953.78 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 953.78 Section 953.78 Agriculture...Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

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7 CFR 958.83 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture...Miscellaneous Provisions § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

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7 CFR 956.91 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 956.91 Section 956.91 Agriculture...Miscellaneous Provisions § 956.91 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

215

7 CFR 927.72 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 927.72 Section 927.72 Agriculture...Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart...

2010-01-01

216

7 CFR 947.83 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture...Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any persons by virtue...

2013-01-01

217

7 CFR 923.67 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 923.67 Section 923.67 Agriculture...Miscellaneous Provisions § 923.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

218

7 CFR 929.72 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 929.72 Section 929.72 Agriculture...Miscellaneous Provisions § 929.72 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

2012-01-01

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7 CFR 927.72 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 927.72 Section 927.72 Agriculture...Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart...

2013-01-01

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7 CFR 966.87 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 966.87 Section 966.87 Agriculture...Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

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7 CFR 966.87 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 966.87 Section 966.87 Agriculture...Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

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7 CFR 947.83 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture...Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any persons by virtue...

2012-01-01

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7 CFR 993.87 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 993.87 Section 993.87 Agriculture...Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

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7 CFR 932.71 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 932.71 Section 932.71 Agriculture...Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

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7 CFR 923.67 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 923.67 Section 923.67 Agriculture...Miscellaneous Provisions § 923.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

226

7 CFR 989.88 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 989.88 Section 989.88 Agriculture...Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

227

7 CFR 923.67 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 923.67 Section 923.67 Agriculture...Miscellaneous Provisions § 923.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

228

7 CFR 929.72 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 929.72 Section 929.72 Agriculture...Miscellaneous Provisions § 929.72 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

2011-01-01

229

7 CFR 916.67 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 916.67 Section 916.67 Agriculture...Miscellaneous Provisions § 916.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

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7 CFR 946.73 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 946.73 Section 946.73 Agriculture...Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

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7 CFR 923.67 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 923.67 Section 923.67 Agriculture...Miscellaneous Provisions § 923.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

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7 CFR 987.80 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 987.80 Section 987.80 Agriculture...Miscellaneous Provisions § 987.80 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

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7 CFR 985.69 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture...Miscellaneous Provisions § 985.69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

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7 CFR 993.87 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 993.87 Section 993.87 Agriculture...Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

235

7 CFR 959.87 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 959.87 Section 959.87 Agriculture...Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

236

7 CFR 916.67 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 916.67 Section 916.67 Agriculture...Miscellaneous Provisions § 916.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

237

7 CFR 947.83 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture...Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any persons by virtue...

2014-01-01

238

7 CFR 946.73 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 946.73 Section 946.73 Agriculture...Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

239

7 CFR 927.72 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 927.72 Section 927.72 Agriculture...Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart...

2012-01-01

240

7 CFR 959.87 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 959.87 Section 959.87 Agriculture...Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

241

7 CFR 981.88 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 981.88 Section 981.88 Agriculture...Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

242

7 CFR 930.86 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 930.86 Section 930.86 Agriculture...Miscellaneous Provisions § 930.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

243

7 CFR 924.67 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 924.67 Section 924.67 Agriculture...Miscellaneous Provisions § 924.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

244

7 CFR 945.86 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture...Miscellaneous Provisions § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

245

7 CFR 915.67 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 915.67 Section 915.67 Agriculture...Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

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7 CFR 993.87 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 993.87 Section 993.87 Agriculture...Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

247

7 CFR 922.67 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 922.67 Section 922.67 Agriculture...Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

248

7 CFR 925.66 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 925.66 Section 925.66 Agriculture...Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

249

7 CFR 906.58 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 906.58 Section 906.58 Agriculture...Miscellaneous Provisions § 906.58 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

250

7 CFR 925.66 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 925.66 Section 925.66 Agriculture...Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

251

7 CFR 927.72 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 927.72 Section 927.72 Agriculture...Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart...

2011-01-01

252

7 CFR 915.67 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 915.67 Section 915.67 Agriculture...Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

253

7 CFR 958.83 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture...Miscellaneous Provisions § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

254

7 CFR 955.82 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 955.82 Section 955.82 Agriculture...Miscellaneous Provisions § 955.82 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

255

7 CFR 945.86 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture...Miscellaneous Provisions § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

256

7 CFR 981.88 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 981.88 Section 981.88 Agriculture...Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

257

7 CFR 925.66 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 925.66 Section 925.66 Agriculture...Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

258

7 CFR 982.84 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 982.84 Section 982.84 Agriculture...Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

259

7 CFR 947.83 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture...Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any persons by virtue...

2011-01-01

260

7 CFR 966.87 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 966.87 Section 966.87 Agriculture...Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

261

7 CFR 925.66 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 925.66 Section 925.66 Agriculture...Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

262

7 CFR 955.82 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 955.82 Section 955.82 Agriculture...Miscellaneous Provisions § 955.82 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

263

7 CFR 932.71 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 932.71 Section 932.71 Agriculture...Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

264

7 CFR 956.91 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 956.91 Section 956.91 Agriculture...Miscellaneous Provisions § 956.91 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

265

7 CFR 989.88 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 989.88 Section 989.88 Agriculture...Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

266

7 CFR 982.84 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 982.84 Section 982.84 Agriculture...Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

267

7 CFR 946.73 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 946.73 Section 946.73 Agriculture...Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

268

7 CFR 946.73 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 946.73 Section 946.73 Agriculture...Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

269

7 CFR 905.85 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 905.85 Section 905.85 Agriculture...Miscellaneous Provisions § 905.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

270

7 CFR 953.78 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 953.78 Section 953.78 Agriculture...Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

271

7 CFR 932.71 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 932.71 Section 932.71 Agriculture...Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

272

7 CFR 982.84 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 982.84 Section 982.84 Agriculture...Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

273

7 CFR 958.83 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture...Miscellaneous Provisions § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

274

7 CFR 932.71 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 932.71 Section 932.71 Agriculture...Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

275

7 CFR 955.82 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 955.82 Section 955.82 Agriculture...Miscellaneous Provisions § 955.82 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

276

7 CFR 953.78 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 953.78 Section 953.78 Agriculture...Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

277

7 CFR 959.87 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 959.87 Section 959.87 Agriculture...Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

278

7 CFR 981.88 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 981.88 Section 981.88 Agriculture...Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

279

7 CFR 984.87 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 984.87 Section 984.87 Agriculture...Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

280

7 CFR 905.85 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 905.85 Section 905.85 Agriculture...Miscellaneous Provisions § 905.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

281

7 CFR 922.67 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 922.67 Section 922.67 Agriculture...Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

282

7 CFR 987.80 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 987.80 Section 987.80 Agriculture...Miscellaneous Provisions § 987.80 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

283

7 CFR 955.82 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 955.82 Section 955.82 Agriculture...Miscellaneous Provisions § 955.82 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

284

7 CFR 987.80 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 987.80 Section 987.80 Agriculture...Miscellaneous Provisions § 987.80 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

285

7 CFR 906.58 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 906.58 Section 906.58 Agriculture...Miscellaneous Provisions § 906.58 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

286

7 CFR 989.88 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 989.88 Section 989.88 Agriculture...Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

287

7 CFR 945.86 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture...Miscellaneous Provisions § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

288

7 CFR 959.87 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 959.87 Section 959.87 Agriculture...Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

289

7 CFR 985.69 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture...Miscellaneous Provisions § 985.69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

290

7 CFR 984.87 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 984.87 Section 984.87 Agriculture...Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

291

7 CFR 993.87 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 993.87 Section 993.87 Agriculture...Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

292

7 CFR 989.88 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 989.88 Section 989.88 Agriculture...Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

293

7 CFR 915.67 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 915.67 Section 915.67 Agriculture...Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

294

7 CFR 917.65 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 917.65 Section 917.65 Agriculture...Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the provisions...

2010-01-01

295

7 CFR 924.67 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 924.67 Section 924.67 Agriculture...Miscellaneous Provisions § 924.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

296

7 CFR 906.58 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 906.58 Section 906.58 Agriculture...Miscellaneous Provisions § 906.58 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

297

7 CFR 925.66 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 925.66 Section 925.66 Agriculture...Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

298

7 CFR 953.78 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 953.78 Section 953.78 Agriculture...Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

299

7 CFR 905.85 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 905.85 Section 905.85 Agriculture...Miscellaneous Provisions § 905.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

300

7 CFR 989.88 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 989.88 Section 989.88 Agriculture...Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

301

7 CFR 906.58 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 906.58 Section 906.58 Agriculture...Miscellaneous Provisions § 906.58 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

302

7 CFR 987.80 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 987.80 Section 987.80 Agriculture...Miscellaneous Provisions § 987.80 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

303

7 CFR 917.65 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 917.65 Section 917.65 Agriculture...Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the...

2012-01-01

304

7 CFR 930.86 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 930.86 Section 930.86 Agriculture...Miscellaneous Provisions § 930.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

305

7 CFR 985.69 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture...Miscellaneous Provisions § 985.69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

306

7 CFR 982.84 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 982.84 Section 982.84 Agriculture...Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

307

7 CFR 932.71 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 932.71 Section 932.71 Agriculture...Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

308

7 CFR 958.83 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture...Miscellaneous Provisions § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

309

7 CFR 915.67 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 915.67 Section 915.67 Agriculture...Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

310

7 CFR 927.72 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 927.72 Section 927.72 Agriculture...Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart...

2014-01-01

311

7 CFR 929.72 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 929.72 Section 929.72 Agriculture...Miscellaneous Provisions § 929.72 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

2014-01-01

312

7 CFR 946.73 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 946.73 Section 946.73 Agriculture...Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

313

7 CFR 915.67 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 915.67 Section 915.67 Agriculture...Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

314

7 CFR 930.86 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 930.86 Section 930.86 Agriculture...Miscellaneous Provisions § 930.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

315

7 CFR 958.83 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture...Miscellaneous Provisions § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

316

7 CFR 922.67 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 922.67 Section 922.67 Agriculture...Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

317

7 CFR 906.58 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 906.58 Section 906.58 Agriculture...Miscellaneous Provisions § 906.58 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

318

7 CFR 985.69 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture...Miscellaneous Provisions § 985.69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

319

7 CFR 947.83 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture...Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any persons by virtue...

2010-01-01

320

7 CFR 993.87 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 993.87 Section 993.87 Agriculture...Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

321

7 CFR 917.65 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 917.65 Section 917.65 Agriculture...Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the provisions...

2011-01-01

322

7 CFR 905.85 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 905.85 Section 905.85 Agriculture...Miscellaneous Provisions § 905.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

323

7 CFR 987.80 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 987.80 Section 987.80 Agriculture...Miscellaneous Provisions § 987.80 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

324

7 CFR 945.86 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture...Miscellaneous Provisions § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

325

7 CFR 945.86 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture...Miscellaneous Provisions § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

326

7 CFR 984.87 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 984.87 Section 984.87 Agriculture...Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

327

7 CFR 966.87 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 966.87 Section 966.87 Agriculture...Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

328

7 CFR 953.78 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 953.78 Section 953.78 Agriculture...Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

329

7 CFR 981.88 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 981.88 Section 981.88 Agriculture...Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

330

7 CFR 966.87 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 966.87 Section 966.87 Agriculture...Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

331

7 CFR 981.88 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 981.88 Section 981.88 Agriculture...Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

332

7 CFR 955.82 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 955.82 Section 955.82 Agriculture...Miscellaneous Provisions § 955.82 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2014-01-01

333

7 CFR 905.85 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 905.85 Section 905.85 Agriculture...Miscellaneous Provisions § 905.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

334

7 CFR 956.91 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 956.91 Section 956.91 Agriculture...Miscellaneous Provisions § 956.91 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

335

7 CFR 922.67 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 922.67 Section 922.67 Agriculture...Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

336

7 CFR 922.67 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 922.67 Section 922.67 Agriculture...Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

337

7 CFR 982.84 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 982.84 Section 982.84 Agriculture...Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

338

7 CFR 917.65 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Duration of immunities. 917.65 Section 917.65 Agriculture...Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the...

2014-01-01

339

7 CFR 984.87 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 984.87 Section 984.87 Agriculture...Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

340

7 CFR 923.67 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Duration of immunities. 923.67 Section 923.67 Agriculture...Miscellaneous Provisions § 923.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2012-01-01

341

7 CFR 917.65 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 917.65 Section 917.65 Agriculture...Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the...

2013-01-01

342

7 CFR 959.87 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 959.87 Section 959.87 Agriculture...Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2013-01-01

343

7 CFR 929.72 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Duration of immunities. 929.72 Section 929.72 Agriculture...Miscellaneous Provisions § 929.72 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

2013-01-01

344

7 CFR 956.91 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Duration of immunities. 956.91 Section 956.91 Agriculture...Miscellaneous Provisions § 956.91 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2010-01-01

345

7 CFR 956.91 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 956.91 Section 956.91 Agriculture...Miscellaneous Provisions § 956.91 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

346

7 CFR 984.87 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Duration of immunities. 984.87 Section 984.87 Agriculture...Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of...

2011-01-01

347

33 CFR 64.23 - Duration of marking on structures.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Duration of marking on structures. 64.23 Section 64.23 Navigation...SECURITY AIDS TO NAVIGATION MARKING OF STRUCTURES, SUNKEN VESSELS AND OTHER OBSTRUCTIONS Structures § 64.23 Duration of marking on...

2010-07-01

348

Long Duration Balloon Charge Controller Stack Integration  

NASA Astrophysics Data System (ADS)

NASA and the Columbia Scientific Balloon Facility are interested in updating the design of the charge controller on their long duration balloon (LDB) in order to enable the charge controllers to be directly interfaced via RS232 serial communication by a ground testing computers and the balloon's flight computer without the need to have an external electronics stack. The design involves creating a board that will interface with the existing boards in the charge controller in order to receive telemetry from and send commands to those boards, and interface with a computer through serial communication. The inputs to the board are digital status inputs indicating things like whether the photovoltaic panels are connected or disconnected; and analog inputs with information such as the battery voltage and temperature. The outputs of the board are 100ms duration command pulses that will switch relays that do things like connect the photovoltaic panels. The main component of this design is a PIC microcontroller which translates the outputs of the existing charge controller into serial data when interrogated by a ground testing or flight computer. Other components involved in the design are an AD7888 12-bit analog to digital converter, a MAX3232 serial transceiver, various other ICs, capacitors, resistors, and connectors.

Clifford, Kyle

349

Space Complexity Algorithms & Complexity  

E-print Network

Space Complexity Algorithms & Complexity Space Complexity Nicolas Stroppa Patrik Lambert - plambert@computing.dcu.ie CA313@Dublin City University. 2008-2009. December 4, 2008 #12;Space Complexity Hierarchy of problems #12;Space Complexity NP-intermediate Languages If P = NP, then are there languages which neither in P

Way, Andy

350

Discretized Time and Conditional Duration Modelling for Stock Transaction Data  

Microsoft Academic Search

The paper considers conditional duration models in which durations are in continuous time but measured in grouped or discretized form. This feature of recorded durations in combination with a frequently traded stock is expected to negatively influence the performance of conventional estimators. A few estimators that account for the discreteness are discussed and compared in a Monte Carlo experiment. An

Kurt Brännäs; Ola Simonsen

2003-01-01

351

Parameterized duration modeling for Switching linear dynamic systems  

Microsoft Academic Search

We introduce an extension of switching linear dy- namic systems (SLDS) with parameterized duration modeling capabilities. The proposed model allows arbi- trary duration models and overcomes the limitation of a geometric distribution induced in standard SLDSs. By incorporating a duration model which ree cts the data more closely, the resulting model provides reliable infer- ence results which are robust against

James M. Rehg; Frank Dellaert

352

Coding rate and duration of vocalizations of the frog, Xenopus laevis.  

PubMed

Vocalizations involve complex rhythmic motor patterns, but the underlying temporal coding mechanisms in the nervous system are poorly understood. Using a recently developed whole-brain preparation from which "fictive" vocalizations are readily elicited in vitro, we investigated the cellular basis of temporal complexity of African clawed frogs (Xenopus laevis). Male advertisement calls contain two alternating components--fast trills (?300 ms) and slow trills (?700 ms) that contain clicks repeated at ?60 and ?30 Hz, respectively. We found that males can alter the duration of fast trills without changing click rates. This finding led us to hypothesize that call rate and duration are regulated by independent mechanisms. We tested this by obtaining whole-cell patch-clamp recordings in the "fictively" calling isolated brain. We discovered a single type of premotor neuron with activity patterns correlated with both the rate and duration of fast trills. These "fast-trill neurons" (FTNs) exhibited long-lasting depolarizations (LLDs) correlated with each fast trill and action potentials that were phase-locked with motor output-neural correlates of call duration and rate, respectively. When depolarized without central pattern generator activation, FTNs produced subthreshold oscillations and action potentials at fast-trill rates, indicating FTN resonance properties are tuned to, and may dictate, the fast-trill rhythm. NMDA receptor (NMDAR) blockade eliminated LLDs in FTNs, and NMDAR activation in synaptically isolated FTNs induced repetitive LLDs. These results suggest FTNs contain an NMDAR-dependent mechanism that may regulate fast-trill duration. We conclude that a single premotor neuron population employs distinct mechanisms to regulate call rate and duration. PMID:22933794

Zornik, Erik; Yamaguchi, Ayako

2012-08-29

353

HIAD at NFAC - Duration: 0:09.  

NASA Video Gallery

Timelapse video of a six-meter (19.7 ft), inflatable Hypersonic Inflatable Aerodynamic Decelerator (HIAD) article being prepared for testing in the National Full-Scale Aerodynamic Complex at Moffet...

354

Aquarius: Tower Rollback - Duration: 2:14.  

NASA Video Gallery

The mobile service tower at NASA's Launch Complex-2 at Vandenberg Air Force Base in California is being moved away from the ULA Delta II rocket with the Aquarius/SAC-D spacecraft atop, in preparati...

355

Supercomputing the Climate - Duration: 5:43.  

NASA Video Gallery

Goddard Space Flight Center is the home of a state-of-the-art supercomputing facility called the NASA Center for Climate Simulation (NCCS) that is capable of running highly complex models to help s...

356

Launch of Juno! - Duration: 2:11.  

NASA Video Gallery

An Atlas V rocket lofted the Juno spacecraft toward Jupiter from Space Launch Complex-41. The 4-ton Juno spacecraft will take five years to reach Jupiter on a mission to study its structure and dec...

357

Unemployment duration and the duration of entitlement to unemployment benefits: an empirical study for Britain  

Microsoft Academic Search

The aim of this paper is to investigate the impact of the expected duration of unemployment benefits on the individual probability of leaving unemployment. The theory predicts that the probability of leaving unemployment will increase near the time of the expected exhaustion of unemployment insurance. Still a limited number of empirical studies is available for European countries. The data used

ELENA G. F. STANCANELLI

1999-01-01

358

Short Duration Base Heating Test Improvements  

NASA Technical Reports Server (NTRS)

Significant improvements have been made to a short duration space launch vehicle base heating test technique. This technique was first developed during the 1960's to investigate launch vehicle plume induced convective environments. Recent improvements include the use of coiled nitrogen buffer gas lines upstream of the hydrogen / oxygen propellant charge tubes, fast acting solenoid valves, stand alone gas delivery and data acquisition systems, and an integrated model design code. Technique improvements were successfully demonstrated during a 2.25% scale X-33 base heating test conducted in the NASA/MSFC Nozzle Test Facility in early 1999. Cost savings of approximately an order of magnitude over previous tests were realized due in large part to these improvements.

Bender, Robert L.; Dagostino, Mark G.; Engel, Bradley A.; Engel, Carl D.

1999-01-01

359

Mapping Regional Precipitation Intensity Duration Frequency Estimates  

NASA Astrophysics Data System (ADS)

For regional precipitation frequency analyses, methods are needed to spatially interpolate or smooth point intensity duration frequency (IDF) estimates at gage sites for the purposes of visualization and estimation at ungaged sites. In this study to update IDF estimates for Michigan, the assumption is made that for practical purposes, the entire state may be treated as a homogeneous region in which annual maximum precipitation is identically distributed at each site apart from a site-specific scaling factor, commonly known as the index flood. Several interpolation and smoothing techniques are evaluated for IDF estimation at ungaged sites, including trend surface analysis, thin plate splines, inverse distance weighting, and several kriging algorithms. Ordinary block kriging is recommended as a practical and objective method for smoothing the variability in the index flood values and developing isopluvial maps.

Watkins, David W., Jr.; Link, Greg A.; Johnson, Dennis

2005-02-01

360

Architectural considerations for lunar long duration habitat  

NASA Astrophysics Data System (ADS)

The future of space exploration science and technology is expected to move toward long duration missions. During this long duration missions the most important factor to success will be the habitation system, the place that crew will live and work. The broad range of future space exploration, new advances in technology and increasing demand for space travel and space tourism will create great opportunities for architects to use their special abilities and skills in the realm of space. The lunar habitat is defined as a multidisciplinary task and cannot be considered an independent project from the main module. Therefore, habitability will become the most important aspect of future human exploration. A successful design strategy should integrate architecture, structure and other disciplines and should bring in elements such as psychological and physiological factors, human interfaces, and privacy. The current research provides "Habitat Architectural Design System (HADS)" in order to evaluate lunar habitat concepts based on habitability, functional optimization, and human factors. HADS helps to promote parametric studied and evaluation of habitat concepts. It will provide a guideline dependent upon mission objectives to standardize architectural needs within the engineering applications and scientific demands. The significance of this research is the process of developing lunar habitat concepts using an architectural system to evaluate the quality of each concept via habitability aspects. This process can be employed during the early stage of design development and is flexible enough to be adjusted by different parameters according to the objectives of lunar mission, limitations, and cost. It also emphasizes the importance of architecture involvement in space projects, especially habitats.

Bahrami, Payam

361

The ATIC long duration balloon project  

NASA Astrophysics Data System (ADS)

Long Duration Balloon (LDB) scientific experiments, launched to circumnavigate the south pole over Antarctica, have particular advantages compared to Shuttle or other Low Earth Orbit (LEO) missions in terms of cost, weight, scientific "duty factor" and work force development. The Advanced Thin Ionization Calorimeter (ATIC) cosmic-ray astrophysics experiment is a good example of a university-based project that takes full advantage of current LDB capability. The ATIC experiment is currently being prepared for its first LDB science flight that will investigate the charge composition and energy spectra of primary cosmic-rays over the energy range from about 10 10 to 10 14 eV. The instrument is built around a fully active, Bismuth-Germanate (BGO) ionization calorimeter to measure the energy deposited by cascades formed by particles interacting in a thick carbon target. A highly segmented silicon matrix, located above the target, provides good incident charge resolution plus rejection of "backscattered" particles from the cascade. Trajectory reconstruction is based on the cascade profile in the BGO calorimeter, plus information from the three pairs of scintillator hodoscope layers in the target section above it. A full evaluation of the experiment was performed during a test flight occurring between 28 December 2000 and 13 January 2001 where ATIC was carried to an altitude of ˜37 km above Antarctica by a ˜850,000 m 3 helium filled balloon for one circumnavigation of the continent. All systems behaved well, the detectors performed as expected, >43 GB of engineering and cosmic-ray event data were returned and these data are now undergoing preliminary data analysis. During the coming 2002-2003 Antarctica summer season, we are preparing for an ATIC science flight with ˜15 to 30 days of data collection in the near-space environment of Long Duration Balloon (LDB) float altitudes.

Guzik, T. G.; Adams, J. H.; Ahn, H. S.; Bashindzhagyan, G.; Chang, J.; Christl, M.; Fazely, A. R.; Ganel, O.; Granger, D.; Gunasingha, R.; Han, Y. J.; Isbert, J. B.; Kim, H. J.; Kim, K. C.; Kim, S. K.; Kouznetsov, E.; Panasyuk, M.; Panov, A.; Price, B.; Samsonov, G.; Schmidt, W. K. H.; Seo, E. S.; Sina, R.; Sokolskaya, N.; Stewart, M.; Voronin, A.; Wang, J. Z.; Wefel, J. P.; Wu, J.; Zatsepin, V.

2004-01-01

362

Long Duration Space Materials Exposure (LDSE)  

NASA Technical Reports Server (NTRS)

The Center on Materials for Space Structures (CMSS) at Case Western Reserve University is one of seventeen Commercial Centers for the Development of Space. It was founded to: (1) produce and evaluate materials for space structures; (2) develop passive and active facilities for materials exposure and analysis in space; and (3) develop improved material systems for space structures. A major active facility for materials exposure is proposed to be mounted on the exterior truss of the Space Station Freedom (SSF). This Long Duration Space Materials Exposure (LDSE) experiment will be an approximately 6 1/2 ft. x 4 ft. panel facing into the velocity vector (RAM) to provide long term exposure (up to 30 years) to atomic oxygen, UV, micro meteorites, and other low earth orbit effects. It can expose large or small active (instrumented) or passive samples. These samples may be mounted in a removable Materials Flight Experiment (MFLEX) carrier which may be periodically brought into the SSF for examination by CMSS's other SSF facility, the Space Materials Evaluation Facility (SMEF), which will contain a Scanning Electron Microscope, a Variable Angle & Scanning Ellipsometer, a Fourier Transform Infrared Spectrometer, and other analysis equipment. These facilities will allow commercial firms to test their materials in space and promptly obtain information on their materials survivability in the LEO environment.

Allen, David; Schmidt, Robert

1992-01-01

363

Immune changes during short-duration missions  

NASA Technical Reports Server (NTRS)

Spaceflight materially influences the immune mechanism of humans and animals. Effects resulting from missions of less than 1 month are examined. Effects from longer missions are discussed in the companion paper by Konstantinova et al. Most immunology studies have involved analyses of subjects and samples from subjects obtained after flight, with the data being compared with similar data obtained before flight. These studies have demonstrated that short-duration missions can result in a postflight depression in blast cell transformation, major changes in cytokine function, and alterations in the relative numbers of immune cell populations. In addition to these post- vs. preflight studies, some data have been produced in flight. However, these in vitro analyses have been less than satisfactory because of differences between in-flight and ground-control conditions. Recently, both the U.S. and Russian space programs have started collecting in-flight, in vivo, cell-mediated immunity data. These studies have confirmed that the human cell-mediated immune system is blunted during spaceflight.

Taylor, G. R.

1993-01-01

364

Parameterized Duration Mmodeling for Switching Linear Dynamic Systems  

Microsoft Academic Search

We introduce an extension of switching linear dy-namic systems (SLDS) with parameterized duration modeling capabilities. The proposed model allows arbi-trary duration models and overcomes the limitation of a geometric distribution induced in standard SLDSs. By incorporating a duration model which re ects the data more closely, the resulting model provides reliable infer-ence results which are robust against observation noise. Moreover,

Sang Min Oh; James M. Rehg; Frank Dellaert

2006-01-01

365

Enhancing Team Performance for Long-Duration Space Missions  

NASA Technical Reports Server (NTRS)

Success of exploration missions will depend on skilled performance by a distributed team that includes both the astronauts in space and Mission Control personnel. Coordinated and collaborative teamwork will be required to cope with challenging complex problems in a hostile environment. While thorough preflight training and procedures will equip creW'S to address technical problems that can be anticipated, preparing them to solve novel problems is much more challenging. This presentation will review components of effective team performance, challenges to effective teamwork, and strategies for ensuring effective team performance. Teamwork skills essential for successful team performance include the behaviors involved in developing shared mental models, team situation awareness, collaborative decision making, adaptive coordination behaviors, effective team communication, and team cohesion. Challenges to teamwork include both chronic and acute stressors. Chronic stressors are associated with the isolated and confined environment and include monotony, noise, temperatures, weightlessness, poor sleep and circadian disruptions. Acute stressors include high workload, time pressure, imminent danger, and specific task-related stressors. Of particular concern are social and organizational stressors that can disrupt individual resilience and effective mission performance. Effective team performance can be developed by training teamwork skills, techniques for coping with team conflict, intracrew and intercrew communication, and working in a multicultural team; leadership and teamwork skills can be fostered through outdoor survival training exercises. The presentation will conclude with an evaluation of the special requirements associated with preparing crews to function autonomously in long-duration missions.

Orasanu, Judith M.

2009-01-01

366

Rashes and Exanthems on Long Duration Space Flights  

NASA Technical Reports Server (NTRS)

INTRODUCTION: As NASA expands its human space exploration to the Moon, Mars and beyond, it will be presented with many challenges, not the least of which will be dealing with medical conditions, which on earth are simple, but take on new levels of complexity in space habitats. Skin conditions exemplify this complexity. METHODS AND RESULTS: While skin conditions account for 7 % of outpatient presentations to a primary care provider in the United States, NASA Longitudinal Study of Astronaut Health (LSAH) database indicates that cutaneous manifestations are significantly prevalent on-orbit. Reviewing this data for US astronauts, there have been 90 total cases of skin rashes during 27.34 person-years of spaceflight, or 3.29 cases/person. Specifically, STS-1 though 114 had 56 cases, ISS Expeditions 1 though 13 had 7 cases, Mir had 4 cases, Skylab had 5 cases and the Apollo program had 18 cases. If there was a period of 24 hours or more between rashes in the same crewmember, this was counted as an additional case. DISCUSSION: This prevalence is likely due, in some part, to constraints of hygiene and to immunologic changes that occur. The stresses of microgravity and austere Earth environments such as the Antarctic, submarine and military deployments, no doubt, similarly contribute to cutaneous reactions; but the difference of the environments are significant enough to warrant further study and discussion. This paper will discuss rashes, exanthems, and cutaneous reactions in space habitats; it will address diagnosis, causation, mitigation and treatment of skin conditions seen on orbit, to date, with a look to anticipating what may be seen with larger crews on future extended duration expeditions.

Ilscus, L.S.; Johnston, S.L.; Moynihan, S.; Kerstman, E.L.; Marshall, G.D.

2009-01-01

367

The ATIC Long Duration Balloon Project  

NASA Astrophysics Data System (ADS)

Long Duration Balloon (LDB) scientific experiments, launched to circumnavigate the south pole over Antarctica, have particular advantages compared to Shuttle or other Low Earth Orbit (LEO) missions in terms of cost, weight, scientific "duty factor" and work force development. The Advanced Thin Ionization Calorimeter (ATIC) cosmic ray astrophysics experiment is a good example of a university-based project that takes full advantage of current LDB capability and could effectively use future expansion in launch weight and flight duration. The ATIC experiment is currently being shipped to Antarctica in preparation for its first LDB science flight that will investigate the charge composition and energy spectra of primary cosmic rays over the energy range from about 101 0 to 10 1 4 eV. The instrument is built around a fully active, Bismuth Germanate (BGO) ionization calorimeter to measure the energy deposited by the cascades formed by particles interacting in a thick carbon target. A highly segmented silicon matrix, located above the target, provides good incident charge resolution plus rejection of the "backscattered" particles from the interaction. Trajectory reconstruction is based on the cascade profile in the BGO calorimeter, plus information from the three scintillator hodoscope layers in the target section above it. The hodoscope planes also provide the primary event trigger to initiate the detector readout, another measure of the incident particle charge and an indicator of the interaction point in the carbon material. The scientific payload weighs ~1,540 kg and consumes ~300 Watts of power supplied by a ~580 Watt solar array system. A full evaluation of the experiment was performed during a test flight occurring between 28 December 2000 and 13 January 2001 where ATIC was carried3 to an altitude of ~37 km above Antarctica by a ~850,000 m helium filled balloon for one circumnavigation of the continent. All systems behaved well, the detectors performed as expected, >43 Gbytes of engineering and cosmic ray event data was returned and these data are now undergoing preliminary data analysis. During the coming 2002-2003 ATIC science flight we will be attempting two circumnavigations of Antarctica or ~30 days of continuous science data collection in the near-space environment of LDB float altitudes. An equivalent scientific "duty factor" is very difficult to achieve in LEO without the expenditure of 100's of millions. Finally, over the course of the ATIC project >60 students (undergraduate and graduate) at the collaborating institutions have gained experience in aerospace systems design, development, fabrication, testing, programming, operation and analysis that would be difficult or impossible to do with a space flight experiment. During the presentation we will discuss the ATIC experiment and detector technologies, the design considerations imposed by LDB launch, termination and recovery constraints, preliminary results from the ATIC test flight, plans for the upcoming science flight and consideration of university-based LDB science projects to the development of tomorrow's aerospace engineers and scientists.

Guzik, T.

368

Asymmetry in perceived duration between up-ramp and down-ramp sounds as a function of duration.  

PubMed

The perceived duration of 1-kHz pure tones with increasing or decreasing intensity profiles was measured. The ratio between the down- and up-ramp durations at equal subjective durations was examined as a function of the sound duration (50, 100, 200, 500, 1000, 2000?ms). At 50 and 100?ms, the ratio was constant and equaled about 1.7, then it logarithmically decreased from 100 to 1000?ms to reach a constant value of 1 at 1 and 2?s. The different mechanisms proposed in the literature to explain the perceived duration asymmetry between up-ramp and down-ramp were discussed in the light of the dependence of this ratio on duration. PMID:25096142

Meunier, Sabine; Vannier, Michaël; Chatron, Jacques; Susini, Patrick

2014-08-01

369

Sleep Duration and Depressive Symptoms: A Gene-Environment Interaction  

PubMed Central

Objective: We used quantitative genetic models to assess whether sleep duration modifies genetic and environmental influences on depressive symptoms. Method: Participants were 1,788 adult twins from 894 same-sex twin pairs (192 male and 412 female monozygotic [MZ] pairs, and 81 male and 209 female dizygotic [DZ] pairs] from the University of Washington Twin Registry. Participants self-reported habitual sleep duration and depressive symptoms. Data were analyzed using quantitative genetic interaction models, which allowed the magnitude of additive genetic, shared environmental, and non-shared environmental influences on depressive symptoms to vary with sleep duration. Results: Within MZ twin pairs, the twin who reported longer sleep duration reported fewer depressive symptoms (ec = -0.17, SE = 0.06, P < 0.05). There was a significant gene × sleep duration interaction effect on depressive symptoms (a'c = 0.23, SE = 0.08, P < 0.05), with the interaction occurring on genetic influences that are common to both sleep duration and depressive symptoms. Among individuals with sleep duration within the normal range (7-8.9 h/night), the total heritability (h2) of depressive symptoms was approximately 27%. However, among individuals with sleep duration within the low (< 7 h/night) or high (? 9 h/night) range, increased genetic influence on depressive symptoms was observed, particularly at sleep duration extremes (5 h/night: h2 = 53%; 10 h/night: h2 = 49%). Conclusion: Genetic contributions to depressive symptoms increase at both short and long sleep durations. Citation: Watson NF; Harden KP; Buchwald D; Vitiello MV; Pack AI; Stachan E; Goldberg J. Sleep duration and depressive symptoms: a gene-environment interaction. SLEEP 2014;37(2):351-358. PMID:24497663

Watson, Nathaniel F.; Harden, Kathryn Paige; Buchwald, Dedra; Vitiello, Michael V.; Pack, Allan I.; Strachan, Eric; Goldberg, Jack

2014-01-01

370

Unemployment Insurance and Male Unemployment Duration in Canada  

Microsoft Academic Search

A model of unemployment duration is estimated with weekly micro data on Canadian men. Ent itlement provisions in the unemployment insurance program and demand conditions are found to have a significant effect on the probability of leaving unemployment. The probability of a worker leaving unemploy ment declines with the duration of unemployment, holding unemployment insurance entitlement constant. When entitlement is

John C. Ham

1987-01-01

371

5 CFR 843.303 - Marriage duration requirements.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Marriage duration requirements. 843.303...Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The...or (2) A child was born of the marriage, as explained in paragraph (c)...

2013-01-01

372

5 CFR 843.303 - Marriage duration requirements.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Marriage duration requirements. 843.303...Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The...or (2) A child was born of the marriage, as explained in paragraph (c)...

2010-01-01

373

5 CFR 843.303 - Marriage duration requirements.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Marriage duration requirements. 843.303...Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The...or (2) A child was born of the marriage, as explained in paragraph (c)...

2011-01-01

374

5 CFR 843.303 - Marriage duration requirements.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Marriage duration requirements. 843.303...Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The...or (2) A child was born of the marriage, as explained in paragraph (c)...

2014-01-01

375

5 CFR 843.303 - Marriage duration requirements.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Marriage duration requirements. 843.303...Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The...or (2) A child was born of the marriage, as explained in paragraph (c)...

2012-01-01

376

Vocalization frequency and duration are coded in separate hindbrain nuclei  

Microsoft Academic Search

Temporal patterning is an essential feature of neural networks producing precisely timed behaviours such as vocalizations that are widely used in vertebrate social communication. Here we show that intrinsic and network properties of separate hindbrain neuronal populations encode the natural call attributes of frequency and duration in vocal fish. Intracellular structure\\/function analyses indicate that call duration is encoded by a

Boris P. Chagnaud; Robert Baker; Andrew H. Bass

2011-01-01

377

Using Phone Durations in Finnish Large Vocabulary Continuous Speech Recognition  

E-print Network

Using Phone Durations in Finnish Large Vocabulary Continuous Speech Recognition Janne Pylkkönen of the languages where phone durations dis­ criminate between words. They therefore have significant meaning, an extension of an existing speech recognition system to include models for discriminatively important phone

Kurimo, Mikko

378

Stimulus Duration Preference at Electrode Sites Yielding Elicited Behavior  

NASA Technical Reports Server (NTRS)

The latency to display eating or drinking during hypothalamic stimulation was compared with the preferred duration of the same stimulus intensity in a self-stimulation situation. All the animals preferred longer stimulus durations than those required to elicit eating or drinking

Cox, V. C.

1970-01-01

379

The influence of stimulus duration on odor perception  

Microsoft Academic Search

Although different parameters are known to alter the shape of olfactory event related potentials (ERP), ERP parameters are generally thought to be independent from stimulus duration. Evidence from recent studies investigating trigeminal ERP indicates that this may not be true. Aim of the present study was to investigate the relationship of stimulus duration and ERP.A total of 20 young healthy

Johannes Frasnelli; Christiane Wohlgemuth; Thomas Hummel

2006-01-01

380

A STUDY ON THE DURATION OF STRONG EARTHQUAKE GROUND MOTION  

Microsoft Academic Search

A simple definition of the duration of strong earthquake ground motion based on the mean-square integral of motion has been presented. It is closely related to that part of the strong motion which contributes significantly to the seismic energy as recorded at a point and to the related spectral amplitudes. Correlations have been established between the duration of strong-motion acceleration,

MI D. TRIFUNAC; A. G. BRADY

1975-01-01

381

The Effect of Student Aid on the Duration of Study  

ERIC Educational Resources Information Center

In this paper I evaluate the effect of student aid on the success of academic studies. I focus on two dimensions, the duration of study and the probability of actually graduating with a degree. To determine the impact of financial student aid, I estimate a discrete-time duration model allowing for competing risks to account for different exit…

Glocker, Daniela

2011-01-01

382

7 CFR 948.87 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Duration of immunities. 948.87 Section 948.87 Agriculture...Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of...

2010-01-01

383

7 CFR 948.87 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Duration of immunities. 948.87 Section 948.87 Agriculture...Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of...

2011-01-01

384

7 CFR 948.87 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Duration of immunities. 948.87 Section 948.87 Agriculture...Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of...

2012-01-01

385

7 CFR 948.87 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Duration of immunities. 948.87 Section 948.87 Agriculture...Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of...

2014-01-01

386

7 CFR 948.87 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Duration of immunities. 948.87 Section 948.87 Agriculture...Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of...

2013-01-01

387

Incoherent Scatter Radar Long Duration Experiments at Millstone Hill  

Microsoft Academic Search

Incoherent scatter radars provide high quality physical measurements of the ionosphere which are useful for a wide variety of investigations Recently an emphasis has been placed on long duration observational runs which last on the order of one month In October 2002 EISCAT Svalbard and Millstone Hill Radars conducted first ever long duration experiments for over 30 consective days Zhang

S. R. Zhang; J. M. Holt; L. P. Goncharenko; J. C. Foster; P. J. Erickson; F. D. Lind

2006-01-01

388

DURATION OF LIFE INSURANCE LIABILITIES AND ASSET LIABILITY MANAGEMENT  

Microsoft Academic Search

The scope of this paper is to analyse duration as a risk measure of life insurance liabilities from traditional life insurance products using a simple model to assess the problem. First, the liabilities are defined. Then the concept of Macauley duration as a measure for interest rate risk with respect to life insurance liabilities is derived. This concept is discussed

RALPH HONEGGER; CHRISTIANE MATHIS

389

The duration and correlates of addiction and treatment careers  

Microsoft Academic Search

While addiction is increasingly recognized as a chronic condition, little information is available on the actual duration of addiction and treatment careers. The purpose of this study was to estimate the duration and correlates of years between (a) first use and at least a year of abstinence and (b) first treatment admission and at least one year of abstinence. Data

Michael L. Dennis; Christy K. Scott; Rodney Funk; Mark A. Foss

2005-01-01

390

Diurnal variation of overdense meteor echo duration and ozone  

NASA Technical Reports Server (NTRS)

The diurnal variation of the median duration of overdense sporadic radar meteor echoes is examined. The meteors recorded in August, December, and January by the Ondrejov meteor radar during the period 1958-1990 were used for the analysis. A maximum median echo duration 1-3 hours after the time of local sunrise in the meteor region confirms the already known sunrise effect. Minimum echo duration occurring at the time of sunset seems to be the most important point of diurnal variation of the echo duration, when ozone is no longer dissociated by solar UV radiation. The effect of diurnal changes of the echo duration should be considered when the mass distribution of meteor showers is analyzed.

Simek, Milos

1992-01-01

391

Overshadowing by fixed- and variable-duration stimuli.  

PubMed

Two experiments investigated the effect of the temporal distribution form of a stimulus on its ability to produce an overshadowing effect. The overshadowing stimuli were either of the same duration on every trial, or of a variable duration drawn from an exponential distribution with the same mean duration as that of the fixed stimulus. Both experiments provided evidence that a variable-duration stimulus was less effective than a fixed-duration cue at overshadowing conditioning to a target conditioned stimulus (CS); moreover, this effect was independent of whether the overshadowed CS was fixed or variable. The findings presented here are consistent with the idea that the strength of the association between CS and unconditioned stimulus (US) is, in part, determined by the temporal distribution form of the CS. These results are discussed in terms of time-accumulation and trial-based theories of conditioning and timing. PMID:25203812

Bonardi, Charlotte; Mondragón, Esther; Brilot, Ben; Jennings, Dómhnall J

2015-03-01

392

The Effects of Long-Duration Spaceflight on Postflight Terrestrial Locomotion  

NASA Technical Reports Server (NTRS)

Locomotion is a complex task requiring the coordinated integration of multiple sensorimotor subsystems. This coordination is exemplified by the precise control of segmental kinematics that allows smooth progression of movement in the face of changing environmental constraints. Exposure to the microgravity environment encountered during space flight induces adaptive modification in the central processing of sensory input to produce motor responses appropriate for the prevailing environment. This inflight adaptive change in sensorimotor function is inappropriate for movement control in 1-g and leads to postflight disturbances in terrestrial locomotor function. We have previously explored the effects of short-duration (7-16 days) space flight on the control of locomotion. The goal of the present set of studies was to investigate the effects of long-duration spaceflight (3-6 months) on the control of locomotion with particular emphasis on understanding how the multiple interacting systems are adaptively modified by prolonged microgravity exposure.

Bloomberg, J. J.; Mulavara, A. P.; McDonald, P. V.; Layne, C. S.; Merkle, L. A.; Cohen, H. S.; Kozlovskaya, I. B.

1999-01-01

393

The role of tone duration in dichotic temporal order judgment.  

PubMed

Over the past two decades, a number of studies have been based on the dichotic temporal order judgment (TOJ) paradigm, to compare auditory temporal processing in various subpopulations to that of young, normal controls. The reported estimates of dichotic TOJ thresholds, expressed as the interstimulus intervals (ISIs) for 75 % accuracy among the controls, have varied. In the present study, we examined the influence of tone duration, within the 10- to 40-msec range, on dichotic TOJ accuracy and threshold. The results indicated that increases in either ISI or tone duration increased dichotic TOJ accuracy similarly, implying that changes in tone duration may affect dichotic TOJs simply by adding to the delay between onset of the tone at the lead ear and onset of the tone at the lag ear. The dichotic TOJ thresholds from three published studies that had used tones as stimuli and the dichotic thresholds from the present study all fell within 0.5 standard deviations from the theoretical line of a 10-msec reduction in threshold for every 10-msec increase in tone duration. When the dichotic TOJ threshold data from the present study and from the published studies were converted to stimulus onset asynchronies (SOAs) and plotted as a function of tone duration, they fell very close to or on a zero-slope line, indicating that when ISI and duration are summed to yield an SOA, dichotic TOJ thresholds are invariant to tone duration within the range of 10-40 msec. PMID:23572206

Babkoff, Harvey; Fostick, Leah

2013-05-01

394

Note: Measurement of extreme-short current pulse duration of runaway electron beam in atmospheric pressure air  

SciTech Connect

This note reports the time-amplitude characteristic of the supershort avalanche electron beam with up to 20 ps time resolution. For the first time it is shown that the electron beam downstream of small-diameter diaphragms in atmospheric pressure air has a complex structure which depends on the interelectrode gap width and cathode design. With a spherical cathode and collimator the minimum duration at half maximum of the supershort avalanche electron beam current pulse was shown to be {approx}25 ps. The minimum duration at half maximum of one peak in the pulses with two peaks can reach {approx}25 ps too.

Tarasenko, V. F.; Rybka, D. V.; Burachenko, A. G.; Lomaev, M. I.; Balzovsky, E. V. [Institute of High Current Electronics SB RAS, 2/3 Akademichesky Ave., 634055 Tomsk (Russian Federation)

2012-08-15

395

Are Durations of Weak Gamma-Ray Bursts Reliable?  

E-print Network

Simulations in the GUSBAD Catalog of gamma-ray bursts suggest that the apparent duration of a burst decreases as its amplitude is decreased. We see no evidence for this effect in the BATSE catalog. We show that for a burst at the detection limit, the typical signal-to-noise ratio at the edges of the T90 duration is around 1.5, suggesting that T90 must be quite uncertain. The situation for T50 is less unfavorable. Simulations using the exact procedure to derive the durations in the BATSE catalog would be useful in quantifying the effect.

Maarten Schmidt

2005-08-16

396

Leaf surface wetness duration measurements by radiogauge and electronic techniques  

SciTech Connect

Comparative measurements of leaf surface wetness duration were made by a beta-ray gauge and an electronic sensor under various wind conditions in the laboratory. Under certain conditions, surface wetness duration measured by the electronic sensor was about 35 minutes shorter than that by the beta-ray gauge. Fair agreement between the sensors at low wind speeds was achieved when the wire grid of the electronic sensor was mounted on a microscope cover glass. Realistic leaf surface wetness duration can be obtained with a beta-ray gauge as it utilizes the attached leaf surfaces rather than artificial ones used on the electronic sensor.

Barthakur, N.N.

1987-01-01

397

Termination of spiral wave breakup in a Fitzhugh-Nagumo model via short and long duration stimuli  

NASA Astrophysics Data System (ADS)

Rotating spiral waves have been observed in a variety of nonlinear biological and physical systems. Spiral waves are found in excitable and oscillatory systems and can be stationary, meander, or even degenerate into multiple unstable rotating waves (a process called "spiral wave breakup"). In the heart, spiral wave breakup is thought to be the underlying mechanism of cardiac fibrillation. The spatiotemporal complexity of multiple unstable spiral waves is difficult to control or terminate. Here, the mechanisms of the termination of spiral wave breakup in response to global stimulation are investigated. A modified Fitzhugh-Nagumo model was used to represent cellular kinetics to study the role of the fast (activation) and slow (recovery) variables. This simplified model allows a theoretical analysis of the termination of spiral wave breakup via both short and long duration pulses. Simulations were carried out in both two-dimensional sheets and in a three-dimensional geometry of the heart ventricles. The short duration pulses affected only the fast variable and acted to reset wave propagation. Monophasic pulses excited tissue ahead of the wave front thus reducing the amount of excitable tissue. Biphasic shocks did the same, but they also acted to generate new wave fronts from the pre-existing wave tails by making some active regions excitable. Thus, if the short duration stimuli were strong enough, they acted to fill in excitable tissue via propagating wave fronts and terminated all activity. The long duration wave forms were selected such that they had a frequency spectrum similar to that of the pseudoelectrocardiograms recorded during fibrillation. These long duration wave forms affected both the recovery and activation variables, and the mechanism of unstable multiple spiral wave termination was different compared to the short duration wave forms. If the long duration stimuli were strong enough, they acted to alter the "state" (i.e., combination of fast and slow variables) of the tissue throughout 1.5 cycles, thus "conditioning" the tissue such that by the end of the stimuli almost no excitable tissue remained. The peak current, total energy, and average power of stimuli required to terminate spiral wave breakup were less for the long duration wave forms compared to the short duration wave forms. In addition, closed loop feedback via stimulation with a wave form that was the difference of the pseudoelectrocardiogram and a strongly periodic chaotic signal was successful at terminating spiral wave breakup. These results suggest that it may be possible to improve cardiac defibrillation efficacy by using long duration wave forms to affect recovery variables in the heart as opposed to the traditional brief duration wave forms that act only on the fast variables.

Gray, Richard A.

2002-09-01

398

The value of the 12-lead ECG for evaluation and optimization of cardiac resynchronization therapy in daily clinical practice.  

PubMed

Based on existing literature and some new data we propose a simple three-step strategy using the standard 12-lead ECG for patient selection and optimal delivery of cardiac resynchronization therapy (CRT). (1) Complete LBBB with regard to the indication for CRT can probably best be identified by a QRS duration of ? 130 ms for women and ? 120 ms for men with the presence of mid-QRS notch-/slurring in ? 2 contiguous leads of V1, V2, V5, V6, I and aVL. (2) Left ventricular (LV) free wall pacing should result in a positive QRS complex in lead V1, with estimation of the exact LV lead position in the circumferential and apico-basal direction using lead aVF and the precordial leads, respectively. Wide and fractionated LV-paced QRS complexes may indicate pacing in scar tissue. (3) Atrioventricular and interventricular stimulation intervals may be optimized by adjusting them until precordial leads show fusion patterns between left and right ventricular activation wavefronts in the QRS complex. PMID:24444866

van Deursen, Caroline J M; Blaauw, Yuri; Witjens, Maryvonne I; Debie, Luuk; Wecke, Liliane; Crijns, Harry J G M; Prinzen, Frits W; Vernooy, Kevin

2014-01-01

399

Electrocardiograms of bottlenose dolphins (Tursiops truncatus) out of water: habituated collection versus wild postcapture animals.  

PubMed

Electrocardiography (ECG) was performed on captured free-ranging bottlenose dolphins (Tursiops truncatus) during a health assessment exercise and compared with that of a Navy collection of dolphins habituated to handling out of water in order to assess possible cardiovascular impacts of capture and handling. Six-lead recordings (I, II, III, aVr, aVl, and aVf) in the frontal plane and direct thorax leads were collected from both groups, with a modified base-apex lead additionally employed with the Navy collection dolphins. Measured and calculated parameters included amplitudes of P, R, S, and T waves and total QRS complex; T:S and T:QRS ratios; heart rate; durations of P wave; QRS complex, PR, QT, and RR intervals; maximum minus minimum RR interval; ST segment elevation-depression; and mean electrical axis (MEA). Physiologically minor but statistically significant differences were detected in S wave amplitude, PR interval, QRS duration, and MEA. The PR interval, QRS duration, and S wave amplitude were slightly greater and the MEA oriented slightly rightward in wild postcapture dolphins compared to Navy collection dolphins. There were no differences in heart rate or maximum minus minimum RR interval, which serves as a proxy for the expected sinus arrhythmia of dolphins. The base-apex lead resulted in greater QRS amplitude than lead II, as expected for the category B ventricular activation of dolphins. The left-side direct thorax lead was more consistent than that of the right side. Clinically, ECG was a useful adjunct to auscultation and thoracic palpation for monitoring heart rate and rhythm and generated a record for archiving. Safe capture and handling protocols in place, under which dolphins are immediately returned to the water at progressive signs of distress, may make cardiovascular decompensation less likely to be detected by ECG. It appears that the dolphin cardiovascular system compensates suitably well to capture, as measured by ECG under the conditions of this study. PMID:24450057

Harms, Craig A; Jensen, Eric D; Townsend, Forrest I; Hansen, Larry J; Schwacke, Lori H; Rowles, Teresa K

2013-12-01

400

7 CFR 983.85 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

...AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE PISTACHIOS GROWN IN CALIFORNIA, ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities....

2013-01-01

401

7 CFR 983.85 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

...AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE PISTACHIOS GROWN IN CALIFORNIA, ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities....

2014-01-01

402

7 CFR 983.85 - Duration of immunities.  

Code of Federal Regulations, 2010 CFR

...AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE PISTACHIOS GROWN IN CALIFORNIA, ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities....

2010-01-01

403

7 CFR 983.85 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

...AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE PISTACHIOS GROWN IN CALIFORNIA, ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities....

2012-01-01

404

7 CFR 983.85 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

...AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE PISTACHIOS GROWN IN CALIFORNIA, ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities....

2011-01-01

405

Sex differences in duration judgments: a meta-analytic review.  

PubMed

We quantitatively reviewed human sex differences in the magnitude and variability of duration judgments. Data from 4,794 females and 4,688 males yielded 87 effect size estimates of magnitude and 28 of variability. The overall sex difference in duration judgment magnitude was small but statistically significant. It was moderated by whether study participants knew in advance (prospective paradigm) or only later (retrospective paradigm) that they would be required to judge duration. Although prospective judgments showed no overall sex effect, some levels of moderator variables showed a small but statistically significant effect. Retrospective judgments showed a larger subjective-to-objective duration ratio for females than for males, and several variables moderated this effect. Females' judgments also showed more intersubject variability than did males' judgments. Relative to males, females sustain attention to time more in the prospective paradigm and have better episodic memory in the retrospective paradigm. PMID:11219961

Block, R A; Hancock, P A; Zakay, D

2000-12-01

406

37 CFR 150.5 - Duration of proclamation.  

Code of Federal Regulations, 2010 CFR

...Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE PROTECTION OF FOREIGN MASK WORKS REQUESTS FOR PRESIDENTIAL PROCLAMATIONS PURSUANT TO 17 U.S.C. 902(a)(2) § 150.5 Duration of...

2010-07-01

407

37 CFR 150.5 - Duration of proclamation.  

Code of Federal Regulations, 2011 CFR

...Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE PROTECTION OF FOREIGN MASK WORKS REQUESTS FOR PRESIDENTIAL PROCLAMATIONS PURSUANT TO 17 U.S.C. 902(a)(2) § 150.5 Duration of...

2011-07-01

408

38 CFR 60.7 - Duration of temporary lodging.  

Code of Federal Regulations, 2011 CFR

...examinations provided at a VA health care facility. When a veteran is undergoing extensive treatment or procedures, such as an organ transplant or chemotherapy, eligible persons may be furnished temporary lodging for the duration of the episode of care...

2011-07-01

409

38 CFR 60.7 - Duration of temporary lodging.  

Code of Federal Regulations, 2010 CFR

...examinations provided at a VA health care facility. When a veteran is undergoing extensive treatment or procedures, such as an organ transplant or chemotherapy, eligible persons may be furnished temporary lodging for the duration of the episode of care...

2010-07-01

410

38 CFR 60.7 - Duration of temporary lodging.  

Code of Federal Regulations, 2012 CFR

...examinations provided at a VA health care facility. When a veteran is undergoing extensive treatment or procedures, such as an organ transplant or chemotherapy, eligible persons may be furnished temporary lodging for the duration of the episode of care...

2012-07-01

411

Volume-Duration-Frequencies for Ungaged Catchments in Texas  

E-print Network

This report summarizes results from studies to determine relationships among the volume, duration and frequencies of floods in ungaged catchments in Texas. Methodologies were adopted for determining flood volumes at unregulated, non-urban catchments...

Devulapalli, Ravi S.; Valdes, Juan B.

412

32 CFR 2400.35 - Duration of classification.  

Code of Federal Regulations, 2013 CFR

...Relating to National Defense OFFICE OF SCIENCE AND TECHNOLOGY POLICY REGULATIONS...IMPLEMENT E.O. 12356; OFFICE OF SCIENCE AND TECHNOLOGY POLICY INFORMATION SECURITY PROGRAM Foreign Government Information § 2400.35 Duration of...

2013-07-01

413

32 CFR 2400.35 - Duration of classification.  

Code of Federal Regulations, 2014 CFR

...Relating to National Defense OFFICE OF SCIENCE AND TECHNOLOGY POLICY REGULATIONS...IMPLEMENT E.O. 12356; OFFICE OF SCIENCE AND TECHNOLOGY POLICY INFORMATION SECURITY PROGRAM Foreign Government Information § 2400.35 Duration of...

2014-07-01

414

10 CFR 430.57 - Duration of temporary exemption.  

Code of Federal Regulations, 2010 CFR

...Section 430.57 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Small Business Exemptions § 430.57 Duration of temporary exemption. A temporary exemption terminates...

2010-01-01

415

10 CFR 451.6 - Duration of incentive payments.  

Code of Federal Regulations, 2011 CFR

...Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of...payments under this part with respect to a qualified renewable energy facility for 10 consecutive fiscal...

2011-01-01

416

10 CFR 451.6 - Duration of incentive payments.  

Code of Federal Regulations, 2014 CFR

...Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of...payments under this part with respect to a qualified renewable energy facility for 10 consecutive fiscal...

2014-01-01

417

10 CFR 451.6 - Duration of incentive payments.  

Code of Federal Regulations, 2010 CFR

...Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of...payments under this part with respect to a qualified renewable energy facility for 10 consecutive fiscal...

2010-01-01

418

10 CFR 451.6 - Duration of incentive payments.  

Code of Federal Regulations, 2012 CFR

...Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of...payments under this part with respect to a qualified renewable energy facility for 10 consecutive fiscal...

2012-01-01

419

7 CFR 3430.1011 - Duration of awards.  

Code of Federal Regulations, 2014 CFR

...FEDERAL ASSISTANCE PROGRAMS-GENERAL AWARD ADMINISTRATIVE PROVISIONS Sun Grant Program § 3430.1011 Duration of awards. The term of a Federal assistance award made under the Sun Grant Program shall not exceed 5 years. No-cost extensions of...

2014-01-01

420

7 CFR 3430.1011 - Duration of awards.  

Code of Federal Regulations, 2013 CFR

...FEDERAL ASSISTANCE PROGRAMS-GENERAL AWARD ADMINISTRATIVE PROVISIONS Sun Grant Program § 3430.1011 Duration of awards. The term of a Federal assistance award made under the Sun Grant Program shall not exceed 5 years. No-cost extensions of...

2013-01-01

421

7 CFR 3430.1011 - Duration of awards.  

Code of Federal Regulations, 2012 CFR

...FEDERAL ASSISTANCE PROGRAMS-GENERAL AWARD ADMINISTRATIVE PROVISIONS Sun Grant Program § 3430.1011 Duration of awards. The term of a Federal assistance award made under the Sun Grant Program shall not exceed 5 years. No-cost extensions of...

2012-01-01

422

7 CFR 3430.1011 - Duration of awards.  

Code of Federal Regulations, 2011 CFR

...FEDERAL ASSISTANCE PROGRAMS-GENERAL AWARD ADMINISTRATIVE PROVISIONS Sun Grant Program § 3430.1011 Duration of awards. The term of a Federal assistance award made under the Sun Grant Program shall not exceed 5 years. No-cost extensions of...

2011-01-01

423

Glioblastoma and Increased Survival with Longer Chemotherapy Duration  

E-print Network

Background: The five year survival for patients with glioblastoma (GBM) is low at approximately 4.7%. Radiotherapy plus concomitant and adjuvant temozolomide (TMZ) remain the standard of care. The optimal duration of therapy with TMZ is unknown...

Aboujaoude, Dory

2013-05-31

424

49 CFR 385.117 - Duration of safety monitoring system.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Duration of safety monitoring system. 385.117 Section...Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS SAFETY FITNESS...

2010-10-01

425

Long Duration Exposure Facility (LDEF). Mission 1 Experiments  

NASA Technical Reports Server (NTRS)

Spaceborne experiments using the space shuttle payload known as the Long Duration Exposure Facility are described. Experiments in the fields of materials, coatings, thermal systems, power and propulsion, electronic, and optics are discussed.

Clark, L. G. (editor); Kinard, W. H. (editor); Carter, D. L., Jr. (editor); Jones, J. L., Jr. (editor)

1984-01-01

426

32 CFR 552.93 - Permit deadline and duration.  

Code of Federal Regulations, 2010 CFR

...OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Fort Lewis Land Use Policy § 552.93 Permit deadline and duration. (a) Permits will be issued 0700-1900 hours daily...

2010-07-01

427

Performance and alertness of railroad engineers on long duration trips  

E-print Network

The present study investigated the performance and alertness of 8 healthy male participants between the age of 31 years and 65 years old in nighttime, long duration simulated train operation. Participants completed the ...

Karnali, Leona D., 1978-

2004-01-01

428

42 CFR 61.38 - Duration of service fellowships.  

Code of Federal Regulations, 2010 CFR

...38 Section 61.38 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Service Fellowships § 61.38 Duration of service fellowships. Initial...

2010-10-01

429

42 CFR 61.13 - Duration and continuation.  

Code of Federal Regulations, 2014 CFR

...13 Section 61.13 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Regular Fellowships § 61.13 Duration and continuation. An award period may be any...

2014-10-01

430

42 CFR 61.13 - Duration and continuation.  

Code of Federal Regulations, 2012 CFR

...13 Section 61.13 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Regular Fellowships § 61.13 Duration and continuation. An award period may be any...

2012-10-01

431

42 CFR 61.38 - Duration of service fellowships.  

Code of Federal Regulations, 2014 CFR

...38 Section 61.38 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Service Fellowships § 61.38 Duration of service fellowships. Initial...

2014-10-01

432

42 CFR 61.13 - Duration and continuation.  

Code of Federal Regulations, 2011 CFR

...13 Section 61.13 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Regular Fellowships § 61.13 Duration and continuation. An award period may be any...

2011-10-01

433

42 CFR 61.13 - Duration and continuation.  

Code of Federal Regulations, 2013 CFR

...13 Section 61.13 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES FELLOWSHIPS, INTERNSHIPS, TRAINING FELLOWSHIPS Regular Fellowships § 61.13 Duration and continuation. An award period may be any...

2013-10-01

434

25 CFR 163.24 - Duration of timber contracts.  

Code of Federal Regulations, 2011 CFR

... 163.24 Section 163.24 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.24 Duration of timber contracts. After the effective date...

2011-04-01

435

25 CFR 163.24 - Duration of timber contracts.  

Code of Federal Regulations, 2012 CFR

... 163.24 Section 163.24 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.24 Duration of timber contracts. After the effective date...

2012-04-01

436

25 CFR 163.24 - Duration of timber contracts.  

Code of Federal Regulations, 2010 CFR

... 163.24 Section 163.24 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.24 Duration of timber contracts. After the effective date...

2010-04-01

437

25 CFR 163.24 - Duration of timber contracts.  

Code of Federal Regulations, 2013 CFR

... 163.24 Section 163.24 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GENERAL FORESTRY REGULATIONS Forest Management and Operations § 163.24 Duration of timber contracts. After the effective date...

2013-04-01

438

7 CFR 920.66 - Duration of immunities.  

Code of Federal Regulations, 2013 CFR

...AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Miscellaneous Provisions § 920.66 Duration of immunities. The benefits, priviliges, and...

2013-01-01

439

7 CFR 920.66 - Duration of immunities.  

Code of Federal Regulations, 2011 CFR

...AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Miscellaneous Provisions § 920.66 Duration of immunities. The benefits, priviliges, and...

2011-01-01

440

7 CFR 920.66 - Duration of immunities.  

Code of Federal Regulations, 2012 CFR

...AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Miscellaneous Provisions § 920.66 Duration of immunities. The benefits, priviliges, and...

2012-01-01

441

7 CFR 920.66 - Duration of immunities.  

Code of Federal Regulations, 2014 CFR

...AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Miscellaneous Provisions § 920.66 Duration of immunities. The benefits, priviliges, and...

2014-01-01

442

Sucking and allosucking duration in farmed red deer ( Cervus elaphus)  

Microsoft Academic Search

Sucking duration in ungulates does not only mean milk transfer, but is also associated with maternal care in general. It seems to be a reflection of offspring demand rather than solely milk transfer rate. Thus, the objective of this study was to discriminate between sucking and allosucking (i.e. sucking non-maternal hind) behaviour in red deer according to the sucking duration.We

Jorga Drabkovaa; Jitka Bartošová; Lud?k Bartoš; Radim Kotrba; Jan Pluhá?ek; Ludmila Švecová; Adam Dušek; Tomáš Kott

2008-01-01

443

Distribution Of Febrile Seizure Duration And Associations With Development  

PubMed Central

Objectives In prior studies of febrile seizures (FS), prolonged FS are defined, absent empirical evidence, as lasting 10 or 15 minutes or more. We assessed the distribution of FS duration in a cohort with first FS, and the association between FS duration and baseline characteristics of the children. Methods We calculated the observed cumulative probability, S(t), that a FS would last at least t minutes, S(t) = exp(?t/ ?) . Data were also fit using a model obtained as the sum of two exponential distributions [S(t) = ?exp(?t/?1)+(1-?)exp(?t/?2)]. After assessing the best fit, the cut off defining long FS was determined. Logisitic regression was used to examine associations between long FS and baseline characteristics, behavior and development. Results In 158 children with a first FS, median duration was 4.0 minutes. Duration of FS was best fit by a two-component mixture exponential model. Using this model we identified one population that accounts for 82.3% of FS and has a mean duration of 3.8 minutes (short FS) and a second population that accounts for 17.7% of FS and has a mean duration of 39.8 minutes (long FS). Long FS were significantly associated with developmental delay (p=0.010) and delays and younger age at first FS (p=0.048). Interpretation Like the distribution of afebrile seizure duration in children, the distribution of first FS duration is best modeled by assuming two populations. Developmental delay and younger age are associated with prolonged FS. Our data lend further support to defining 10 minutes as the upper limit for a simple FS. PMID:21437934

Hesdorffer, Dale C.; Benn, Emma K.T.; Bagiella, Emilia; Nordli, Douglas; Pellock, John; Hinton, Veronica; Shinnar, Shlomo

2011-01-01

444

Stroboscope motion: Effects of duration and interval1  

Microsoft Academic Search

The quality of stroboscope motion induced by the successive presentation of two illuminated squares obeys two rules. For all\\u000a stimulus durations shorter than 100 msec, optimal motion occurs when the stimulus onsets differ by about 120 msec. For stimulus\\u000a durations longer than 100 msec, optimal motion occurs when the second stimulus begins at the termination of the first stimulus.\\u000a The

Daniel Kahneman; Ruth E. Wolman

1970-01-01

445

Strategies for crew selection for long duration missions  

NASA Technical Reports Server (NTRS)

Issues surrounding psychological reactions to long duration spaceflight are discussed with respect to the definition of criteria for selecting crewmembers for such expeditions. Two broad dimensions of personality and behavior are defined - Instrumentality including achievement orientation, leadership, and ability to perform under pressure and Expressivity encompassing interpersonal sensitivity and competence. A strategy for validating techniques to select in candidates with the optimum psychological profile to perform successfully on long duration missions is described.

Helmreich, Robert L.; Holland, Albert W.; Santy, Patricia A.; Rose, Robert M.; Mcfadden, Terry J.

1990-01-01

446

Regulating intensity using perceived exertion: effect of exercise duration  

Microsoft Academic Search

To examine whether the validity of perception-based intensity regulation would be affected by exercise duration, 20 subjects\\u000a were recruited to complete a maximal exercise test (GXT) and four submaximal trials of varying duration and intensity using\\u000a a cyle ergometer. During GXT, ratings of perceived exertion (RPE), oxygen uptake (VO2), heart rate (HR), and power output (PO) equivalent to 50 and

Jie Kang; Edward C. Chaloupka; Gregory B. Biren; M. Alysia Mastrangelo; Jay R. Hoffman

2009-01-01

447

Introduction to duration concepts: application to bank management  

E-print Network

INTRODUCTION TO DURATION CONCEPTS: APPLICATION TO BANK MANAGEMENT A Professional Paper by Alison J. Meyers Submitted to the College of Agriculture of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER... OP AGRICULTURE May 1985 Agricultural Economics Agribanking INTRODUCTION TO DURATION CONCEPTS: APPLICATION TO BANK MANAGEMENT A Professional Paper by Alison J. Meyers prov as to style a content by: n Hopkin, irma , Advisory Committee David...

Meyers, Alison J.

1985-01-01

448

Particle Astrophysics in NASA's Long Duration Balloon Program  

E-print Network

A century after Viktor Hess' discovery of cosmic rays, balloon flights still play a central role in the investigation of cosmic rays over nearly their entire spectrum. We report on the current status of NASA balloon program for particle astrophysics, with particular emphasis on the very successful Antarctic long-duration balloon program, and new developments in the progress toward ultra-long duration balloons.

Gorham, Peter W

2013-01-01

449

Effects of exposure duration and recovery time during pulsed exposures.  

PubMed

In pulsed toxicant exposures, the concentration, duration, and frequency of pulses can change through time. However, the conventional median lethal concentration (LC50) method cannot adequately predict the effects of pulsed exposure, because it is associated with fixed exposure duration and constant concentration and does not include postexposure (latent) mortality. Many studies that tried to address the effects of pulsed exposure only provided qualitative or semiquantitative predictions. Survival time experiments conducted here quantified the effect of exposure duration on latent mortality, and the effect of recovery time between two pulses on mortality during a second pulse also was examined. This was done by exposing amphipods (Hyalella azteca) to two contrasting toxicants, copper sulfate (CuSO4) and sodium pentachlorophenol (NaPCP). In the exposure duration experiments, the amphipods were exposed to two toxicant concentrations for three durations. No significant effect of duration on latent mortality was detected within the experimental range; however, duration still may need to be considered under other conditions. In the recovery time experiments, the amphipods were provided four recovery times, and their survivals during the second exposure were modeled. Recovery time had a significant effect on the second-exposure mortality. Given enough time, the amphipods could recover to a state similar to their original toxicant resistance state. The complete recovery time for CuSO4 was fivefold longer than that for NaPCP. It is important to quantify the effects of latent mortality, pulse duration and concentration, and recovery time for pulsed exposures. Survival analysis provides a better way to address these issues than does the conventional LC50 method. PMID:16704061

Zhao, Yuan; Newman, Michael C

2006-05-01

450

Development of long-duration ballooning in Antarctica  

SciTech Connect

Following four successful long-duration test flights from Australia to South America, a new flight support system with global tracking, command, and telemetry capability is being developed to support long-duration balloon flights of relatively sophisticated instruments at both mid-latitudes and in Antarctica. The first test flight for the joint NASA-NSF program to support flights in Antarctica is scheduled from McMurdo in December 1989, with operational capability two years later.

Jones, W.V. (National Aeronautics and Space Administration, Code ES, Space Physics Division, Washington, DC 20546 (USA))

1990-03-20

451

Insomnia with Short Sleep Duration: Nosological, Diagnostic, and Treatment Implications.  

PubMed

The diagnosis of insomnia is based solely on subjective complaints. This has contributed to the low reliability and validity of the current nosology of insomnia as well as to its lack of firm association with clinically relevant outcomes such as cardiometabolic and neurocognitive morbidity. We review evidence that insomnia with objective short sleep duration is associated with physiological hyperarousal, higher risk for hypertension, diabetes, neurocognitive impairment, and mortality as well as with a persistent course. It also appears that objective short sleep duration in poor sleepers is a biological marker of genetic predisposition to chronic insomnia. In contrast, insomnia with objective normal sleep duration is associated with cognitive-emotional and cortical arousal and sleep misperception but not with signs of physiological hyperarousal or medical complications. Thus, short sleep duration in insomnia may be a reliable marker of the biological severity and medical impact of the disorder. We propose that (a) objective measures of sleep be included in the diagnosis of insomnia and its subtypes, (b) objective measures of sleep obtained in the home environment of the patient would become part of the routine assessment and diagnosis of insomnia in a clinician's office setting, and (c) insomnia with short sleep duration may respond better to biological treatments, whereas insomnia with normal sleep duration may respond primarily to psychological therapies. PMID:24072989

Vgontzas, Alexandros N; Fernandez-Mendoza, Julio

2013-09-01

452

The effect of tone duration on auditory stream formation.  

PubMed

In a study in which the effect of tone duration on the formation of auditory streams was investigated, subjects were presented with 15-sec alternating pure-tone sequences (ABAB...) and were asked to orient their attention over the duration of the sequence toward hearing either a temporally coherent or a segregated percept. At stimulus offset, the subjects indicated whether their percept at the end of the stimulus had been that of a temporally coherent ABAB trill or that of segregated A and B streams. The experimental results indicated that the occurrence of stream segregation increases as (1) the duration of the A and B tones increases in unison and (2) the difference in duration between the A and B tones increases, with the duration differences between the tones producing the strongest segregation effects. A comparison of these experimental results with those of other studies strongly suggests that the time interval between the offset and onset of consecutive tones in the same frequency range is the most important temporal factor affecting auditory stream formation. Furthermore, a simulation of the experimental results by the Beauvois and Meddis (1996) stream segregation model suggests that both the tone duration effects reported here and Gestalt auditory grouping on the basis of temporal proximity can be understood in terms of low-level neurophysiological processes and peripheral-channeling factors. PMID:9682609

Beauvois, M W

1998-07-01

453

Asymmetric processing of durational differences - electrophysiological investigations in Bengali.  

PubMed

Duration is used contrastively in many languages to distinguish word meaning (e.g. in Bengali, [pata] 'leaf' vs. [pat:a] 'whereabouts'). While there is a large body of research on other contrasts in speech perception (e.g. vowel contrasts and consonantal place features), little work has been done on how durational information is used in speech processing. In non-linguistic studies of low-level processing, such as visual and non-linguistic acoustic pop-out tasks, an asymmetry is found where additional information is more readily detected than missing information. In this study, event-related potentials were recorded during two cross-modal auditory-visual semantic priming studies, where nonword mispronunciations of spoken prime words were created by changing the duration of a medial consonant (real word [dana] 'seed'>nonword [dan:a]). N400 amplitudes showed an opposite asymmetric pattern of results, where increases in consonantal duration were tolerated and led to priming of the visual target, but decreases in consonantal duration were not accepted. This asymmetrical pattern of acceptability is attributed to the fact that a longer consonant includes all essential information for the recognition of the original word with a short medial consonant (a possible default category) and any additional information can be ignored. However, when a consonant is shortened, it lacks the required durational information to activate the word with the original long consonant. PMID:24726333

Roberts, Adam C; Kotzor, Sandra; Wetterlin, Allison; Lahiri, Aditi

2014-05-01

454

Differences in duration of untreated illness, duration, and severity of illness among clinical phenotypes of obsessive-compulsive disorder.  

PubMed

Introduction Obsessive-compulsive disorder (OCD) is a prevalent, disabling, and comorbid condition that is frequently under-recognized and poorly treated. OCD phenotypes may differ in terms of clinical presentation and severity. However, few studies have investigated whether clinical phenotypes differ in terms of latency to treatment (ie, duration of untreated illness[DUI]), duration, and severity of illness. The present study was aimed to quantify the aforementioned variables in a sample of OCD patients. PMID:24967664

Dell'Osso, Bernardo; Benatti, Beatrice; Oldani, Lucio; Spagnolin, Gregorio; Altamura, A Carlo

2014-06-26

455

The Association of Urbanicity with Infant Sleep Duration  

PubMed Central

Short sleep duration is associated with multiple adverse child outcomes. We examined associations of the built environment with infant sleep duration among 1226 participants in a pre-birth cohort. From residential addresses, we used a geographic information system to determine urbanicity, population density, and closeness to major roadways. The main outcome was mother’s report of her infant’s average daily sleep duration at 1 year of age. We ranked urbanicity and population density as quintiles, categorized distance to major roads into 8 categories, and used linear regression adjusted for socio-demographic characteristics, smoking during pregnancy, gestational age, fetal growth, and television viewing at 1 year. In this sample, mean (SD) sleep duration at age 1 year was 12.8 (1.6) hours/day. In multivariable adjusted analyses, children living in the highest quintile of urbanicity slept ?19.2 minutes/day (95% CI: ?37.0, ?1.50) less than those living in the lowest quintile. Neither population density nor closeness to major roadways was associated with infant sleep duration after multivariable adjustment. Our findings suggest that living in more urban environments may be associated with reduced infant sleep. PMID:22795497

Bottino, Clement J.; Rifas-Shiman, Sheryl L.; Kleinman, Ken P.; Oken, Emily; Redline, Susan; Gold, Diane; Schwartz, Joel; Melly, Steven J.; Koutrakis, Petros; Gillman, Matthew W.; Taveras, Elsie M.

2012-01-01

456

Earth-Space Links and Fade-Duration Statistics  

NASA Technical Reports Server (NTRS)

In recent years, fade-duration statistics have been the subject of several experimental investigations. A good knowledge of the fade-duration distribution is important for the assessment of a satellite communication system's channel dynamics: What is a typical link outage duration? How often do link outages exceeding a given duration occur? Unfortunately there is yet no model that can universally answer the above questions. The available field measurements mainly come from temperate climatic zones and only from a few sites. Furthermore, the available statistics are also limited in the choice of frequency and path elevation angle. Yet, much can be learned from the available information. For example, we now know that the fade-duration distribution is approximately lognormal. Under certain conditions, we can even determine the median and other percentiles of the distribution. This paper reviews the available data obtained by several experimenters in different parts of the world. Areas of emphasis are mobile and fixed satellite links. Fades in mobile links are due to roadside-tree shadowing, whereas fades in fixed links are due to rain attenuation.

Davarian, Faramaz

1996-01-01

457

Earth-space links and fade-duration statistics  

NASA Technical Reports Server (NTRS)

In recent years, fade-duration statistics have been the subject of several experimental investigations. A good knowledge of the fade-duration distribution is important for the assessment of a satellite communication system's channel dynamics: What is a typical link outage duration? How often do link outages exceeding a given duration occur? Unfortunately there is yet no model that can universally answer the above questions. The available field measurements mainly come from temperate climatic zones and only from a few sites. Furthermore, the available statistics are also limited in the choice of frequency and path elevation angle. Yet, much can be learned from the available information. For example, we now know that the fade-duration distribution is approximately lognormal. Under certain conditions, we can even determine the median and other percentiles of the distribution. This paper reviews the available data obtained by several experimenters in different parts of the world. Areas of emphasis are mobile and fixed satellite links. Fades in mobile links are due to roadside-tree shadowing, whereas fades in fixed links are due to rain attenuation.

Davarian, Faramaz

1995-01-01

458

Incident Duration Modeling Using Flexible Parametric Hazard-Based Models  

PubMed Central

Assessing and prioritizing the duration time and effects of traffic incidents on major roads present significant challenges for road network managers. This study examines the effect of numerous factors associated with various types of incidents on their duration and proposes an incident duration prediction model. Several parametric accelerated failure time hazard-based models were examined, including Weibull, log-logistic, log-normal, and generalized gamma, as well as all models with gamma heterogeneity and flexible parametric hazard-based models with freedom ranging from one to ten, by analyzing a traffic incident dataset obtained from the Incident Reporting and Dispatching System in Beijing in 2008. Results show that different factors significantly affect different incident time phases, whose best distributions were diverse. Given the best hazard-based models of each incident time phase, the prediction result can be reasonable for most incidents. The results of this study can aid traffic incident management agencies not only in implementing strategies that would reduce incident duration, and thus reduce congestion, secondary incidents, and the associated human and economic losses, but also in effectively predicting incident duration time.

2014-01-01

459

Competing risks mixture model for traffic incident duration prediction.  

PubMed

Traffic incident duration is known to result from a combination of multiple factors, including covariates such as spatial and temporal characteristics, traffic conditions, and existence of secondary accidents but also the clearance method itself. In this paper, a competing risks mixture model is used to investigate the influence of clearance methods and various covariates on the duration of traffic incidents and predict traffic incident duration. The proposed mixture model considers the uncertainty in any of five clearance methods that occurred. The probability of the clearance method is specified in the mixture by using a multinomial logistic model. Three candidate distributions, namely, generalized gamma, Weibull, and log-logistic are tested to determine the most appropriate probability density function of the parametric survival analysis model. The unobserved heterogeneity is also incorporated into the mixture model in a way that allows parameters to vary across observations based on the three candidate distributions. The methods are illustrated with incident data from Singaporean expressways from January 2010 to December 2011. Regression analysis reveals that the probability of different clearance methods and the duration of traffic incidents are both significantly affected by various factors, such as traffic conditions and incident characteristics. Results show that the proposed mixture model is better than the traditional accelerated failure time model, and it predicts traffic incident duration with reasonable accuracy, as shown by the mean average percent error. PMID:25485730

Li, Ruimin; Pereira, Francisco C; Ben-Akiva, Moshe E

2014-12-01

460

Space Station as a Long Duration Exposure Facility  

NASA Technical Reports Server (NTRS)

There is need for a space platform for experiments investigating long duration exposure to space. This platform should be maintainable in the event of a malfunction, and experiments should be easily recoverable for analysis on Earth. The International Space Station provides such a platform. The current Space Station configuration has six external experiment attachment sites, providing utilities and data support distributed along the external truss. There are also other sites that could potentially support long duration exposure experiments. This paper describes the resources provided to payloads at these sites, and cites examples of integration of proposed long duration exposure experiments on these sites. The environments to which external attached payloads will be exposed are summarized.

Folley, Adrienne; Scheib, Jim

1995-01-01

461

Long Duration Testing of Type C Thermocouples at 1500 °C  

SciTech Connect

Experience with Type C thermocouples operating for long periods in the 1400 to 1600 °C temperature range indicate that significant decalibration occurs, often leading to expensive downtime and material waste. As part of an effort to understand the mechanisms causing drift in these thermocouples, the Idaho National Laboratory conducted a long duration test at 1500 °C containing eight Type C thermocouples. As report in this document, results from this long duration test were adversely affected due to oxygen ingress. Nevertheless, results provide key insights about the impact of precipitate formation on thermoelectric response. Post-test examinations indicate that thermocouple signal was not adversely impacted by the precipitates detected after 1,000 hours of heating at 1,500 °C and suggest that the signal would not have been adversely impacted by these precipitates for longer durations (if oxygen ingress had not occurred in this test).

Joy L. Rempe; Darrell L. Knudson; J. E. Daw; S. C. Wilkins

2008-04-01

462

Relationship Between Maximum Tsunami Amplitude and Duration of Signal  

NASA Astrophysics Data System (ADS)

All available tsunami observations at tide gauges situated along the North American coast were examined to determine if there is any clear relationship between maximum amplitude and signal duration. In total, 89 historical tsunami recordings generated by 13 major earthquakes between 1952 and 2011 were investigated. Tidal variations were filtered out of the signal and the duration between the arrival time and the time at which the signals drops and stays below 0.3 m amplitude was computed. The processed tsunami time series were evaluated and a linear least-squares fit with a 95 % confidence interval was examined to compare tsunami durations with maximum tsunami amplitude in the study region. The confidence interval is roughly 20 h over the range of maximum tsunami amplitudes in which we are interested. This relatively large confidence interval likely results from variations in local resonance effects, late-arriving reflections, and other effects.

Kim, Yoo Yin; Whitmore, Paul M.

2014-12-01

463

Fade durations in satellite-path mobile radio propagation  

NASA Astrophysics Data System (ADS)

Fades on satellite to land mobile radio links are caused by several factors, the most important of which are multipath propagation and vegetative shadowing. Designers of vehicular satellite communications systems require information about the statistics of fade durations in order to overcome or compensate for the fades. Except for a few limiting cases, only the mean fade duration can be determined analytically, and all other statistics must be obtained experimentally or via simulation. This report describes and presents results from a computer program developed at Virginia Tech to simulate satellite path propagation of a mobile station in a rural area. It generates rapidly-fading and slowly-fading signals by separate processes that yield correct cumulative signal distributions and then combines these to simulate the overall signal. This is then analyzed to yield the statistics of fade duration.

Schmier, Robert G.; Bostian, Charles W.

1986-12-01

464

Fade durations in satellite-path mobile radio propagation  

NASA Technical Reports Server (NTRS)

Fades on satellite to land mobile radio links are caused by several factors, the most important of which are multipath propagation and vegetative shadowing. Designers of vehicular satellite communications systems require information about the statistics of fade durations in order to overcome or compensate for the fades. Except for a few limiting cases, only the mean fade duration can be determined analytically, and all other statistics must be obtained experimentally or via simulation. This report describes and presents results from a computer program developed at Virginia Tech to simulate satellite path propagation of a mobile station in a rural area. It generates rapidly-fading and slowly-fading signals by separate processes that yield correct cumulative signal distributions and then combines these to simulate the overall signal. This is then analyzed to yield the statistics of fade duration.

Schmier, Robert G.; Bostian, Charles W.

1986-01-01

465

How do changes in speed affect the perception of duration?  

PubMed

Six experiments investigated how changes in stimulus speed influence subjective duration. Participants saw rotating or translating shapes in three conditions: constant speed, accelerating motion, and decelerating motion. The distance moved and average speed were the same in all three conditions. In temporal judgment tasks, the constant-speed objects seemed to last longer than the decelerating objects, which in turn seemed to last longer than the accelerating stimuli. In temporal reproduction tasks, the difference between accelerating and decelerating stimuli disappeared; furthermore, watching an accelerating shape lengthened the apparent duration of the subsequent (static) display. These results (a) suggest that temporal judgment and reproduction can dissociate for moving stimuli because the stimulus influences the apparent duration of the subsequent interval, and (b) constrain theories of time perception, including those which emphasize memory storage, those which emphasize the existence of a pacemaker-accumulator timing system, and those which emphasize the division of attention between temporal and non-temporal information processing. PMID:21517218

Matthews, William J

2011-10-01

466

Sleep Duration and Weight Gain: Reconsideration by Panel Data Analysis  

PubMed Central

Background Inconsistent findings in previous studies of the association between sleep duration and changes in body mass index (BMI) may be attributed to misclassification of sleep duration fluctuations over time and unmeasured confounders such as genetic factors. The aim of the present study was to overcome these failings by using repeated measurements and panel data analysis to examine the sleep-BMI association. Methods Panel data were derived by secondary use of the data from mandatory health checkups at a Japanese gas company. Male non-shift workers aged 19–39 years in 2007 were annually followed until 2010 (n = 1687, 6748 records). BMI was objectively measured, and sleep duration was self-reported. Results Compared with 7-hour sleepers, panel analysis with the population-averaged model showed a significant increase in BMI among 5-hour (0.11 kg/m2, P = 0.001), 6-hour (0.07 kg/m2, P = 0.038), and ?8-hour (0.19 kg/m2, P = 0.009) sleepers. On the other hand, after adjustment for unobserved time-invariant confounders using the fixed-effects model, the magnitude of the association was considerably attenuated and no longer significant (5-hour, 0.07 kg/m2, P = 0.168; 6-hour, 0.02 kg/m2, P = 0.631; ?8-hour sleepers, 0.06 kg/m2, P = 0.460). Conclusions The longitudinal association between sleep duration and changes in BMI may be upwardly biased by unobserved time-invariant confounders rather than misclassified sleep duration. The net effect of sleep duration on weight gain may therefore be less than previously believed. PMID:25088695

Nishiura, Chihiro; Hashimoto, Hideki

2014-01-01

467

Comparison of Postural Recovery Following Short and Long Duration Spaceflights  

NASA Technical Reports Server (NTRS)

INTRODUCTION: Post-flight postural ataxia reflects adaptive changes to vestibulo-spinal reflexes and control strategies adopted for movement in weightlessness. Quantitative measures obtained during computerized dynamic posturography (CDP) from US and Russian programs provide insight into the effect of spaceflight duration in terms of both the initial decrements and recovery of postural stability. METHODS: CDP was obtained on 117 crewmembers following Shuttle flights lasting 4-17 days, and on 64 crewmembers following long-duration missions lasting 48-380 days. Although the number and timing of sessions varied, the goal was to characterize postural recovery pooling similar measures from different research and flight medicine programs. This report focuses on eyes closed, head erect conditions with either a fixed or sway-referenced base of support. A smaller subset of subjects repeated the sway-referenced condition while making pitch head movements (+/- 20deg at 0.33Hz). Equilibrium scores were derived from peak-to-peak anterior-posterior sway. Fall probability was modeled using Bayesian statistical methods to estimate parameters of a logit function. RESULTS: The standard Romberg condition was the least sensitive. Longer duration flights led to larger decrements in stability with sway-reference support during the first 1-2 days, although the timecourse of recovery was similar across flight duration with head erect. Head movements led to increased incidence of falls during the first week, with a significantly longer recovery following long duration flights. CONCLUSIONS: The diagnostic assessment of postural instability, and differences in the timecourse of postural recovery between short and long flight durations, are more pronounced during unstable support conditions requiring active head movements.

Wood, S. J.; Fiedler, J.; Taylor, L. C.; Kozlovskaya, I.; Black, F. O.; Paloski, W. H.

2010-01-01

468

Atom interferometry using ?-kicked and finite-duration pulse sequences  

NASA Astrophysics Data System (ADS)

We investigate an atom interferometer in which large momentum differences between the arms are obtained by using quantum resonances in the atom-optics ?-kicked rotor. The interferometer can potentially measure the Talbot time (from which h/m can be deduced) and the local gravitational field or can serve as a narrow velocity filter. We present an analytical analysis in the short pulse limit and a numerical investigation for finite pulse durations. The sensitivity of the interferometer is improved by a moderate violation of the short pulse limit. Remarkably simple relations predict the optimal pulse duration and the sensitivity of the interferometer.

Daszuta, Boris; Andersen, Mikkel F.

2012-10-01

469

Planning in time - Windows and durations for activities and goals  

NASA Technical Reports Server (NTRS)

The present general purpose automated planner/scheduler generates parallel plans aimed at the achievement of goals having imposed time constraints, with both durations and start time windows being specifiable for sets of goal conditions. Deterministic durations of such parallel plan activities as actions, events triggered by circumstances, inferences, and scheduled events entirely outside the actor's control, are explicitly modeled and may be any computable function of the activity variables. The final plan network resembles a PERT chart. Examples are given from the traditional 'blocksworld', and from a realistic 'Spaceworld' in which an autonomous spacecraft photographs objects in deep space and transmits the information to earth.

Vere, S. A.

1983-01-01

470

Crew productivity issues in long-duration space flight  

NASA Technical Reports Server (NTRS)

Considerable evidence suggests the importance of teamwork, coordination, and conflict resolution to the performance and survival of isolated, confined groups in high-technology environments. With the advent of long-duration space flight, group-related issues of crew functioning will take on added significance. This paper discusses the influence of crew roles, status, leadership, and norms on the performance of small, confined groups, and offers guidelines and suggestions regarding organizational design, crew selection, training, and team building for crew productivity and social well-being in long-duration spaceflight.

Nicholas, John M.; Foushee, H. Clayton; Ulschak, Francis L.

1988-01-01

471

Cognitive Assessment in Long-Duration Space Flight  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the development and use of a tool for assessing spaceflight cognitive ability in astronauts. This tool. the Spaceflight Cognitive Assessment Tool for Windows (WinSCAT) has been used to provide ISS flight surgeons with an objective clinical tool to monitor the astronauts cognitive status during long-duration space flight and allow immediate feedback to the astronaut. Its use is medically required for all long-duration missions and it contains a battery of five cognitive assessment subtests that are scheduled monthly and compared against the individual preflight baseline.

Kane, Robert; Seaton, Kimberly; Sipes, Walter

2011-01-01

472

Believing Is Seeing: Fixation Duration Predicts Implicit Negative Attitudes  

PubMed Central

A prototypical finding of social cognition is that social experiences influence later performance even though those experiences are not introspectively available. Building on social cognition research on implicit attitudes, we evaluate whether ethnic category/attribute pairs influence eye movements during the Implicit Association Test (IAT, Greenwald, McGhee, & Schwartz 1998). Results show that fixation duration predicted implicit attitudes such that when the category/attribute pairs disconfirmed one's implicit negative attitude fixation duration toward that pair increased. The present research provides evidence that eye movements and implicit processes inherent in the IAT are more broadly connected than previously thought. PMID:25133639

2014-01-01

473

Concept definition for an extended duration orbiter ECLSS  

NASA Technical Reports Server (NTRS)

Extending the seven-day Shuttle Orbiter baseline mission requires an evaluation of the Environmental Control and Life Support (ECLS) System in order to determine those changes necessary or desirable so that the Orbiter payload capability will not be seriously compromised. The ECLSS requirements and subsystem options for extended duration Orbiter missions are defined. Each major ECLS subsystem was examined, and potential methods of extending the mission capability were studied. The mission evaluated most extensively for this effort was a 30 day mission with a crew size of seven men. However, missions up to 90 days duration with crew sizes of three to ten men were also examined.

Brose, H.

1977-01-01

474

LRO Exposes the Moon's Complex, Turbulent Youth - Duration: 0:53.  

NASA Video Gallery

Using the Lunar Reconnaissance Orbiter?s Lunar Orbiter Laser Altimeter (LOLA), NASA scientists have created the first-ever comprehensive catalog of large craters on the moon. In this animation, lun...

475

Duration or Disadvantage? Exploring Nativity, Ethnicity, and Health in Midlife  

Microsoft Academic Search

Objectives . This study examined nativity as a risk factor for poor physical and emotional health for an ethnically di- verse population making the transition into retirement. The authors addressed whether the health disadvantage observed for immigrants lessens with increased time spent in the country (supporting theories of assimilation) or increases with duration of residence (supporting theories of cumulative disadvantage).

Jacqueline L. Angel; Cynthia J. Buckley; Art Sakamoto

2001-01-01

476

Fixed-Duration Therapy in Leprosy: Limitations and Opportunities  

PubMed Central

Leprosy has been considered a curable disease after the implementation of multidrug therapy (MDT), which has been proven to be safe and effective, by bringing about a significant change in the global and national scenario of leprosy by upgrading the control of leprosy to the next stage of eradication. Since its introduction, the MDT regimens for the treatment of leprosy have undergone several changes especially with regard to the duration of treatment. The advantages of shortened duration of treatment need to be balanced against the risk of relapse and a lot of controversies exist pertaining to this aspect. The fixed-duration (FD) therapy is not popular among academicians and private practitioners who prefer precise diagnosis and treatment with superior MDT regimens and for a longer duration. On the contrary, from a public health-care point of view, precise diagnosis and a longer treatment schedule are not cost effective and not feasible to be implemented in elimination programs. Hence, a fine balance needs to be maintained between achieving a cure for the patient and protecting the society at risk, and this review discusses the various limitations and opportunities of FD therapy with a note on the newer MDT regimens. PMID:23716796

Malathi, Munisamy; Thappa, Devinder Mohan

2013-01-01

477

Duration of ultrasound bubbles enhanced cell membrane permeability  

Microsoft Academic Search

Purpose: Ultrasound (US) has shown the ability to modulate the cell membrane permeability in a process known as sonoporation. In addition, the sonoporation process has been proven to be amplified when US is associated with contrast microbubbles. The purpose of this study is to quantify the duration of the sonoporation process for external molecules with different sizes. Method: monolayers of

Annemieke van Wamel; Ayache Bouakaz; Nico de Jong

2003-01-01

478

The Effect of Congenital Deafness on Duration Judgment  

ERIC Educational Resources Information Center

Objective: Congenital deafness provides the opportunity to study how atypical sensory and language experiences affect different aspects of information processing, e.g., time perception. Methods: Using two methods of temporal estimation, reproduction (Exp. 1) and production (Exp. 2), the effect of deafness on duration judgment was investigated…

Kowalska, Joanna; Szelag, Elzbieta

2006-01-01

479

The effects of odor and body posture on perceived duration.  

PubMed

This study reports an examination of the internal clock model, according to which subjective time duration is influenced by attention and arousal state. In a time production task, we examine the hypothesis that an arousing odor and an upright body posture affect perceived duration. The experimental task was performed while participants were exposed to an odor and either sitting upright (arousing condition) or lying down in a relaxing chair (relaxing condition). They were allocated to one of three experimental odor conditions: rosemary (arousing condition), peppermint (relaxing condition), and no odor (control condition). The predicted effects of the odors were not borne out by the results. Self-reported arousal (SRA) and pleasure (PL) states were measured before, during (after each body posture condition) and postexperimentally. Heart rate (HR) and skin conductance were measured before and during the experiment. As expected, odor had an effect on perceived duration. When participants were exposed to rosemary odor, they produced significantly shorter time intervals than in the no odor condition. This effect, however, could not be explained by increased arousal. There was no effect of body posture on perceived duration, even though body posture did induce arousal. The results do not support the proposed arousal mechanism of the internal clock model. PMID:24567718

Schreuder, Eliane; Hoeksma, Marco R; Smeets, Monique A M; Semin, Gün R

2014-01-01

480

A simple technique for individual picosecond laser pulse duration measurements  

NASA Technical Reports Server (NTRS)

We describe here a simple nonlinear optic technique for the measurement of the duration of individual picosecond pulses. The accuracy and relative simplicity of the technique increase with the number of pulses measured. An experimental test of the basis of the technique is described.

Smith, W. L.; Bechtel, J. H.

1976-01-01

481

The Pros of Procalcitonin: Reducing Antibiotic Duration in the ICU  

E-print Network

Antonio September 9, 2011 Learning Objectives 1. Describe adverse consequences of antibiotic overuse. Consequences of antibiotic overuse i. Promotion of multi-drug resistant (MDR) pathogens 1. Antibiotic use1 The Pros of Procalcitonin: Reducing Antibiotic Duration in the ICU Elizabeth A. Oates, Pharm

Pillow, Jonathan

482

How Do Changes in Speed Affect the Perception of Duration?  

ERIC Educational Resources Information Center

Six experiments investigated how changes in stimulus speed influence subjective duration. Participants saw rotating or translating shapes in three conditions: constant speed, accelerating motion, and decelerating motion. The distance moved and average speed were the same in all three conditions. In temporal judgment tasks, the constant-speed…

Matthews, William J.

2011-01-01

483

A Factored Language Model of Quantized Pitch and Duration  

Microsoft Academic Search

This paper investigates a novel statistical approach to mu- sic classication that utilizes recent technology developed in the domain of natural language processing. Specically , we investigate the use of factored language models (FLMs) for the task of producing conditional probability distributions to model origin-specic folk songs. In our model, pitch cluster and quantized duration are employed as the two

Xiao Li; Gang Ji; Jeff Bilmes

484

Effect of pulse duration on two-photon excited  

E-print Network

of the pulse duration for the entire tested range. Because of improved signal-to-noise ratio, sub-20-fs pulses the spatial, spectral, and temporal properties of laser sources. Generally, femtosecond pulsed lasers increase in TPEF yield when laser pulses were compressed from 250 to 35 fs.4 Xu and Webb examined

Chen, Zhongping

485

The Effects of Duration of Caregiving on Institutionalization  

ERIC Educational Resources Information Center

Purpose: Our objective in this analysis was to determine how the duration of caregiving interacts with key care demands (i.e., severity of problem behaviors) to influence the institutionalization of individuals suffering from dementia. Methods: We utilized multiregional data from 4,761 caregivers of individuals with dementia over a 3-year period.…

Gaugler, Joseph E.; Kane, Robert L.; Kane, Rosalie A.; Clay, Ted; Newcomer, Robert C.

2005-01-01

486

Breastfeeding in Iran: prevalence, duration and current recommendations  

Microsoft Academic Search

BACKGROUND: The need to promote breastfeeding is unquestionable for the health and development of infants. The aim of this study was to investigate prevalence, duration and promotion of breastfeeding status in Iran with respect to the Baby Friendly Hospital, government actions and activities by the Breastfeeding Promotion Society including comparison with European countries. METHODS: This retrospective study is based on

Beheshteh Olang; Khalil Farivar; Abtin Heidarzadeh; Birgitta Strandvik; Agneta Yngve

2009-01-01

487

Spectral loudness summation as a function of duration  

NASA Astrophysics Data System (ADS)

Loudness was measured as a function of signal bandwidth for 10-, 100-, and 1000-ms-long signals. The test and reference signals were bandpass-filtered noise spectrally centered at 2 kHz. The bandwidth of the test signal was varied from 200 to 6400 Hz. The reference signal had a bandwidth of 3200 Hz. The reference levels were 45, 55, and 65 dB SPL. The level to produce equal loudness was measured with an adaptive, two-interval, two-alternative forced-choice procedure. A loudness matching procedure was used, where the tracks for all signal pairs to be compared were interleaved. Mean results for nine normal-hearing subjects showed that the magnitude of spectral loudness summation depends on signal duration. For all reference levels, a 6- to 8-dB larger level difference between equally loud signals with the smallest (?f=200 Hz) and largest (?f=6400 Hz) bandwidth is found for 10-ms-long signals than for the 1000-ms-long signals. The duration effect slightly decreases with increasing reference loudness. As a consequence, loudness models should include a duration-dependent compression stage. Alternatively, if a fixed loudness ratio between signals of different duration is assumed, this loudness ratio should depend on the signal spectrum.

Verhey, Jesko L.; Kollmeier, Birger

2002-03-01

488

Long Duration Space Missions: Human Subsystem Risks and Requirements  

NASA Technical Reports Server (NTRS)

This viewgraph presentation reviews the human health and performance risks associated with long duration space flight beyond low earth orbit. The contents include: 1) Human Research Program; 2) Human Subsystem Risks; 3) Human Exploration Framework Team (HEFT) Architecture Elements; 4) Potentially Unacceptable Risks -1; 5) Potentially Unacceptable Risks-2; and 6) Major Mission Drivers of Risk.

Kundrot, Criag E.

2011-01-01

489

Human factors in long-duration space flight  

NASA Technical Reports Server (NTRS)

A study, covering the behavioral, psychological, physiological, and medical factors of long duration manned space flight, is presented. An attempt was made to identify and resolve major obstacles and unknowns associated with such a flight. The costs and maintenance of the spacecraft system are also explored.

1972-01-01

490

Temporal Context in Concurrent Chains: I. Terminal-Link Duration  

ERIC Educational Resources Information Center

Two experiments are reported in which the ratio of the average times spent in the terminal and initial links ("Tt/Ti") in concurrent chains was varied. In Experiment 1, pigeons responded in a three-component procedure in which terminal-link variable-interval schedules were in constant ratio, but their average duration increased across components…

Grace, Randolph C.

2004-01-01

491

DURATION NORMALIZATION FOR ROBUST RECOGNITION OF SPONTANEOUS SPEECH  

E-print Network

DURATION NORMALIZATION FOR ROBUST RECOGNITION OF SPONTANEOUS SPEECH VIA MISSING FEATURE METHODS Jon recognition and transcription. In response to casual speech, ASR systems produce more than twice as many. Automatic identification of unknown boundary locations, however, has proven to be a difficult problem. When

Stern, Richard

492

Attention, Exposure Duration, and Gaze Shifting in Naming Performance  

ERIC Educational Resources Information Center

Two experiments are reported in which the role of attribute exposure duration in naming performance was examined by tracking eye movements. Participants were presented with color-word Stroop stimuli and left- or right-pointing arrows on different sides of a computer screen. They named the color attribute and shifted their gaze to the arrow to…

Roelofs, Ardi

2011-01-01

493

Recent activities for long duration flight systems in Japan  

NASA Astrophysics Data System (ADS)

For the feasibility studies of the long duration balloon systems in recent times in Japan, the forces was on following items. • An analysis to utilize the Pumpkin Balloons for the over pressurized balloons, and to develop the simple automatic gas pressure control systems for the long duration flights. • Test flights by the balloon group of the Institute of Space and Astronautical Science (ISAS) to see the performance of the balloons of new films of EVAL (Ethylene-Vinyl-Alcohol) having strong absorption bands of the infra-red between 7-14 microns. We expect that this absorption prevents the cooling of the lifting gas after the sun-sets, and thus save the ballast consumption. • A sea recovery system beyond 100-200 km from the Pacific coast by using helicopters with ARGOS/GPS. The situation would be applicable to the sea recovery of payloads after the long duration flights at the turn-around period launched from Sanriku Balloon Center. The flight performances have already been proved in the 1975 and 77 achieving the duration of 55, 65, 80 hrs keeping the locations of payloads within 200 km from the sea coast. • Studies on the high altitude balloons with thin polyethylene films are also reported in this paper.

Nishimura, J.

494

The effects of odor and body posture on perceived duration  

PubMed Central

This study reports an examination of the internal clock model, according to which subjective time duration is influenced by attention and arousal state. In a time production task, we examine the hypothesis that an arousing odor and an upright body posture affect perceived duration. The experimental task was performed while participants were exposed to an odor and either sitting upright (arousing condition) or lying down in a relaxing chair (relaxing condition). They were allocated to one of three experimental odor conditions: rosemary (arousing condition), peppermint (relaxing condition), and no odor (control condition). The predicted effects of the odors were not borne out by the results. Self-reported arousal (SRA) and pleasure (PL) states were measured before, during (after each body posture condition) and postexperimentally. Heart rate (HR) and skin conductance were measured before and during the experiment. As expected, odor had an effect on perceived duration. When participants were exposed to rosemary odor, they produced significantly shorter time intervals than in the no odor condition. This effect, however, could not be explained by increased arousal. There was no effect of body posture on perceived duration, even though body posture did induce arousal. The results do not support the proposed arousal mechanism of the internal clock model. PMID:24567718

Schreuder, Eliane; Hoeksma, Marco R.; Smeets, Monique A. M.; Semin, Gün R.

2013-01-01

495

Practitioner Empathy and the Duration of the Common Cold  

PubMed Central

Objective To assess the relationship of empathy in medical consultations to subsequent cold outcomes. Methods 350 subjects, ?12 years of age received either a standard or enhanced physician visit as part of a randomized controlled trial. The patient-scored Consultation and Relational Empathy (CARE) questionnaire assessed practitioner-patient interaction, especially empathy. Cold severity and duration were assessed from twice daily symptom reports. Nasal wash was performed to measure the immune cytokine IL-8. Results 84 individuals reported perfect (score of 50) CARE scores. They tended to be older with less education, but reported similar health status, quality of life, and levels of optimism. In those with perfect CARE scores, cold duration was shorter (mean 7.10 days vs. 8.01 days, p=0.032), and there was a trend towards reduced severity (mean AUC 240.40 vs. 284.49, p=0.118). After accounting for possible confounding variables, cold severity and duration were significantly lower in those reporting perfect CARE scores (p=0.037 and p=0.017 respectively). In these models, a perfect score also correlates with a larger increase in IL-8 levels (p=0.015). Conclusions Clinician empathy, as perceived by patients with the common cold, significantly predicts subsequent duration and severity of illness and is associated with immune system changes. PMID:19582635

Rakel, David P.; Hoeft, Theresa J.; Barrett, Bruce P.; Chewning, Betty A.; Craig, Benjamin M.; Niu, Min

2009-01-01

496

Determinants of duration of unemployment insurance benefits in Turkey  

Microsoft Academic Search

This article is the first empirical study on the duration of unemployment insurance benefits in Turkey. Turkey has adopted an unemployment insurance programme in 2000, and the first payment of the benefit was made in 2002. Thus, it is new and the first programme to partially compensate the income of workers when they are unemployed. The unemployment insurance programme has

Hasan Sahin; A. Burca Kizilirmak

2007-01-01

497

The duration of invalidity benefit claims: a proportional hazard model  

Microsoft Academic Search

This paper analyses the duration of Invalidity Benefit claims in Great Britain among men and women. The Cox proportional hazard model is used to estimate the effect of personal characteristics and economic factors on the claimants' probability of leaving the benefit. On the whole, similar results were obtained for the male and female models, although labour market-related factors appear to

Mauricea Lynch

1991-01-01

498

Strike incidence and strike duration: Some new evidence from Ontario  

Microsoft Academic Search

The authors use a unique longitudinal data set from Ontario, covering the years 1984-92, to estimate the determinants of strike incidence and duration. Unlike most empirical analyses of strikes, the data set for this study contains both small and large bargaining units. The authors find strong evidence that the likelihood of a future strike was lower among bargaining units that

Michele Campolieti; Robert Hebdon; Douglas Hyatt

2005-01-01

499

Acoustic and Durational Properties of Indian English Vowels  

ERIC Educational Resources Information Center

This paper presents findings of an acoustic phonetic analysis of vowels produced by speakers of English as a second language from northern India. The monophthongal vowel productions of a group of male speakers of Hindi and male speakers of Punjabi were recorded, and acoustic phonetic analyses of vowel formant frequencies and vowel duration were…

Maxwell, Olga; Fletcher, Janet

2009-01-01

500

An evaluation of factors affecting duration of orthodontic treatment  

Microsoft Academic Search

One of the first questions asked by new orthodontic patients is: How long will I need to wear my braces? A multitude of factors have the potential to influence the answer to this question. The purpose of this retrospective study was to identify some of the primary factors that influence orthodontic treatment duration. Few studies have attempted to evaluate these

F. Richard Beckwith; Richard J. Ackerman; Charles M Cobb; Daniel E. Tira

1999-01-01