Science.gov

Sample records for qrs complex duration

  1. Prognostic significance of QRS duration and morphology.

    PubMed

    Brenyo, Andrew; Zaręba, Wojciech

    2011-01-01

    QRS duration and morphology, evaluated via a standard 12-lead electrocardiogram (ECG), represent an opportunity to derive useful prognostic information regarding the risk of subsequent cardiac events or therapeutic outcomes. Prolonged QRS duration, and the presence of intraventricular conduction abnormalities, usually indicate the presence of changes in the myocardium due to underlying heart disease. Prolonged QRS duration is often associated with depressed ejection fraction or enlarged left ventricular volumes, but several studies have demonstrated that this simple ECG measure provides independent prognostic value, after adjusting for relevant clinical covariates. Post-infarction patients with prolonged QRS duration have a significantly increased risk of mortality, although data associating QRS prolongation specifically with sudden death is less supportive. In non-ischemic cardiomyopathy, there is no evidence that QRS duration has prognostic significance in predicting mortality or sudden death. Prolonged QRS duration, and especially presence of left bundle branch block, seems to predict a benefit from cardiac resynchronization therapy in both ischemic and non-ischemic cardiomyopathy patients. Therefore, QRS duration and morphology should not only be considered a predictor of death or sudden death in patients after myocardial infarction, and in those suspected of coronary artery disease, but also as a predictor of benefit from cardiac resynchronization therapy in patients with heart failure, whether of an ischemic or non-ischemic origin. PMID:21305480

  2. Simple and Robust Realtime QRS Detection Algorithm Based on Spatiotemporal Characteristic of the QRS Complex.

    PubMed

    Kim, Jinkwon; Shin, Hangsik

    2016-01-01

    The purpose of this research is to develop an intuitive and robust realtime QRS detection algorithm based on the physiological characteristics of the electrocardiogram waveform. The proposed algorithm finds the QRS complex based on the dual criteria of the amplitude and duration of QRS complex. It consists of simple operations, such as a finite impulse response filter, differentiation or thresholding without complex and computational operations like a wavelet transformation. The QRS detection performance is evaluated by using both an MIT-BIH arrhythmia database and an AHA ECG database (a total of 435,700 beats). The sensitivity (SE) and positive predictivity value (PPV) were 99.85% and 99.86%, respectively. According to the database, the SE and PPV were 99.90% and 99.91% in the MIT-BIH database and 99.84% and 99.84% in the AHA database, respectively. The result of the noisy environment test using record 119 from the MIT-BIH database indicated that the proposed method was scarcely affected by noise above 5 dB SNR (SE = 100%, PPV > 98%) without the need for an additional de-noising or back searching process. PMID:26943949

  3. Relation of QRS duration to mortality in a community-based cohort with hypertrophic cardiomyopathy.

    PubMed

    Bongioanni, Sergio; Bianchi, Francesca; Migliardi, Alessandro; Gnavi, Roberto; Pron, Paolo Giay; Casetta, Marzia; Conte, Maria Rosa

    2007-08-01

    A prolonged QRS duration on the standard electrocardiogram is associated with an increased risk of cardiovascular death in cardiomyopathies of different origin. However, the relation between QRS duration and prognosis in hypertrophic cardiomyopathy (HC) remains undefined. We assessed the relation between QRS duration and cardiovascular death in 241 consecutive patients with HC. The study cohort was divided into 2 groups according to QRS duration: <120 and > or =120 ms. Of the 241 patients, 191 (79%) had a QRS duration <120 ms and 50 (21%) a QRS duration > or =120 ms. During a mean follow-up of 7.9 +/- 5.1 years, 35 patients died of cardiovascular causes related to HC. Of these 35 patients, 13 (6%) had a QRS duration <120 ms and 22 (43%) had a QRS duration > or =120 ms (p <0.01). Risk of cardiovascular death was significantly higher in patients with a QRS duration > or =120 ms than in those with a QRS duration <120 ms (relative risk 5.2, p <0.0001). At 8-year follow-up, cumulative risks of HC-related death were 7.1% in patients with a QRS duration <120 ms and 55% in those with a QRS duration > or =120 ms. Multivariate analysis confirmed that a QRS duration > or =120 ms was independently associated with an increased risk of cardiovascular death (hazard ratio 3.2, p = 0.007). New York Heart Association functional class III/IV was the only other clinical variable significantly and independently associated with an increased risk of cardiovascular death. In conclusion, in patients with HC, QRS duration on standard electrocardiogram is directly related to cardiovascular mortality, and a QRS duration > or =120 ms is a strong and independent predictor of prognosis.

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

    SciTech Connect

    Cros, C.; Skinner, M.; Moors, J.; Lainee, P.; Valentin, J.P.

    2012-12-01

    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

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

    PubMed

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

    2014-03-01

    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.

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

    PubMed

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

    2014-03-01

    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

  7. Detection of the QRS complex by linear prediction.

    PubMed

    Hadj Slimane, Z E; Bereksi Reguig, F

    2006-01-01

    The electrocardiogram (ECG) represents the electrical activity of the heart. It is characterized by its recurrent or periodic behaviour with each beat. Each recurrence is composed of a wave sequence consisting of P, QRS and T-waves, where the most characteristic wave set is the QRS complex. In this paper, we have developed an algorithm for detection of the QRS complex. The algorithm consists of several steps: signal-to-noise enhancement, linear prediction for ECG signal analysis, nonlinear transform, moving window integrator, centre-clipping transformation and QRS detection. Linear prediction determines the coefficients of a forward linear predictor by minimizing the prediction error by a least-square approach. The residual error signal obtained after processing by the linear prediction algorithm has very significant properties which will be used to localize and detect QRS complexes. The detection algorithm is tested on ECG signals from the universal MIT-BIH arrhythmia database and compared with the Pan and Tompkins QRS detection method. The results we obtain show that our method performs better than this method. Our algorithm results in fewer false positives and fewer false negatives. PMID:16772215

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

    PubMed Central

    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.; te Meerman, Gerard; 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

    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

  9. Left ventricular pacing improves haemodynamic variables in patients with heart failure with a normal QRS duration

    PubMed Central

    Turner, M S; Bleasdale, R A; Mumford, C E; Frenneaux, M P; Morris-Thurgood, J A

    2004-01-01

    Objectives: To assess whether patients with congestive heart failure (CHF) and a normal QRS duration can benefit from left ventricular (VDD-LV) pacing. Design: Cardiac resynchronisation is reserved for patients with a broad QRS duration on the premise that systolic resynchronisation is the mechanism of benefit, yet improvement from pacing correlates poorly with QRS duration. In CHF patients with a broad QRS duration, those with a high resting pulmonary capillary wedge pressure (PCWP) > 15 mm Hg benefit. In this acute haemodynamic VDD-LV pacing study, patients with CHF with a normal QRS duration were divided into two groups—patients with a resting PCWP > 15 mm Hg and patients with a resting PCWP < 15 mm Hg—to determine whether benefit is predicted by a high resting PCWP. Patients: 20 patients with CHF, New York Heart Association functional class IIb–IV, all with a normal QRS duration (⩽ 120 ms). Interventions: Temporary pacing wires were positioned to enable VDD-LV pacing and a pulmonary artery catheter was inserted for measurement of PCWP, right atrial pressure, and cardiac output. Results: In patients with a PCWP > 15 mm Hg (n  =  10), cardiac output increased from 3.9 (1.5) to 4.5 (1.65) l/min (p < 0.01), despite a fall in PCWP from 24.7 (7.1) to 21.0 (6.2) mm Hg (p < 0.001). In patients with a PCWP < 15 mm Hg there was no change in PCWP or cardiac output. Combined data showed that PCWP decreased from 17.0 (9.1) to 15.3 (7.7) mm Hg during VDD-LV pacing (p < 0.014) and cardiac output increased non-significantly from 4.7 (1.5) to 4.9 (1.5) (p  =  0.125). Conclusions: Patients with CHF with a normal QRS duration and PCWP > 15 mm Hg derive acute haemodynamic benefit from VDD-LV pacing. PMID:15084543

  10. Detection of segments with fetal QRS complex from abdominal maternal ECG recordings using support vector machine

    NASA Astrophysics Data System (ADS)

    Delgado, Juan A.; Altuve, Miguel; Nabhan Homsi, Masun

    2015-12-01

    This paper introduces a robust method based on the Support Vector Machine (SVM) algorithm to detect the presence of Fetal QRS (fQRS) complexes in electrocardiogram (ECG) recordings provided by the PhysioNet/CinC challenge 2013. ECG signals are first segmented into contiguous frames of 250 ms duration and then labeled in six classes. Fetal segments are tagged according to the position of fQRS complex within each one. Next, segment features extraction and dimensionality reduction are obtained by applying principal component analysis on Haar-wavelet transform. After that, two sub-datasets are generated to separate representative segments from atypical ones. Imbalanced class problem is dealt by applying sampling without replacement on each sub-dataset. Finally, two SVMs are trained and cross-validated using the two balanced sub-datasets separately. Experimental results show that the proposed approach achieves high performance rates in fetal heartbeats detection that reach up to 90.95% of accuracy, 92.16% of sensitivity, 88.51% of specificity, 94.13% of positive predictive value and 84.96% of negative predictive value. A comparative study is also carried out to show the performance of other two machine learning algorithms for fQRS complex estimation, which are K-nearest neighborhood and Bayesian network.

  11. The association between prolongation in QRS duration and presence of coronary collateral circulation in patients with acute myocardial infarction

    PubMed Central

    Altıntaş, Bernas; Uğurlu, Murat; Kaya, İlyas; Uçaman, Berzal; Uluğ, Ali Veysel; Altındağ, Rojhat; Altaş, Yakup; Adıyaman, Mehmet Şahin; Öztürk, Önder

    2016-01-01

    Background It is known that QRS duration is related to prognosis in acute myocardial infarction. The relation between QRS duration and coronary collateral circulation is uncertain. In the present study, we aimed to determine the relation between QRS duration and coronary collateral circulation in patients admitted with acute myocardial infarction. Methods The present study was composed of 109 consecutive patients with acute myocardial infarction. All patients had total occlusion in the left anterior descending coronary artery. Electrocardiographic recordings on admission were obtained for the assessment of QRS duration. The Rentrop classification was used to define coronary collateral circulation on coronary angiography. Patients were divided into two groups as follows: Group 1 with poor coronary collateral circulation (Rentrop 0–1) and Group 2 with good coronary collateral circulation (Rentrop 2–3). Results Of all patients, 62 patients were included in group 1 and 47 patients in group 2, respectively. In the present study, patients in the group 1 had longer QRS duration than patients in the group 2 (p < 0.005). Additionally, we found that Rentrop grading had negative correlation with both QRS duration and white blood cell count (r: −0.28; p < 0.005 and r: −0.35; p < 0.001). Conclusion Our study showed that there was an inverse relationship between QRS duration on admission and presence of coronary collateral circulation in patients with acute myocardial infarction. PMID:27570619

  12. Termination of acute wide QRS complex atrial fibrillation with ibutilide.

    PubMed

    Sobel, R M; Dhruva, N N

    2000-07-01

    Ibutilide is a Vaughan-Williams class III antiarrhythmic agent approved for chemical cardioversion of acute onset atrial fibrillation/flutter. Emergency physicians rarely use ibutilide despite its proven clinical value. We report a case of successful chemical cardioversion using ibutilide in a patient with atrial fibrillation and delayed ventricular depolarization (wide QRS complex). We recommend that ibutilide be considered for wider use in the emergency department and that further studies be conducted.

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

    PubMed Central

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

    2013-01-01

    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 (χ2 = 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

  14. Current Algorithms for the Diagnosis of wide QRS Complex Tachycardias

    PubMed Central

    Vereckei, András

    2014-01-01

    The differential diagnosis of a regular, monomorphic wide QRS complex tachycardia (WCT) mechanism represents a great diagnostic dilemma commonly encountered by the practicing physician, which has important implications for acute arrhythmia management, further work-up, prognosis and chronic management as well. This comprehensive review discusses the causes and differential diagnosis of WCT, and since the ECG remains the cornerstone of WCT differential diagnosis, focuses on the application and diagnostic value of different ECG criteria and algorithms in this setting and also provides a practical clinical approach to patients with WCTs. PMID:24827795

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

    NASA Astrophysics Data System (ADS)

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

    2007-12-01

    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.

  16. Ethnic differences in the association of QRS duration with ejection fraction and outcome in heart failure

    PubMed Central

    Gijsberts, Crystel M; Benson, Lina; Dahlström, Ulf; Sim, David; Yeo, Daniel P S; Ong, Hean Yee; Jaufeerally, Fazlur; Leong, Gerard K T; Ling, Lieng H; Richards, A Mark; de Kleijn, Dominique P V; Lund, Lars H; Lam, Carolyn S P

    2016-01-01

    Background QRS duration (QRSd) criteria for device therapy in heart failure (HF) were derived from predominantly white populations and ethnic differences are poorly understood. Methods We compared the association of QRSd with ejection fraction (EF) and outcomes between 839 Singaporean Asian and 11 221 Swedish white patients with HF having preserved EF (HFPEF)and HF having reduced EF (HFREF) were followed in prospective population-based HF studies. Results Compared with whites, Asian patients with HF were younger (62 vs 74 years, p<0.001), had smaller body size (height 163 vs 171 cm, weight 70 vs 80 kg, both p<0.001) and had more severely impaired EF (EF was <30% in 47% of Asians vs 28% of whites). Overall, unadjusted QRSd was shorter in Asians than whites (101 vs 104 ms, p<0.001). Lower EF was associated with longer QRSd (p<0.001), with a steeper association among Asians than whites (pinteraction<0.001), independent of age, sex and clinical covariates (including body size). Excluding patients with left bundle branch block (LBBB) and adjusting for clinical covariates, QRSd was similar in Asians and whites with HFPEF, but longer in Asians compared with whites with HFREF (p=0.001). Longer QRSd was associated with increased risk of HF hospitalisation or death (absolute 2-year event rate for ≤120 ms was 40% and for >120 ms it was 52%; HR for 10 ms increase of QRSd was 1.04 (1.03 to 1.06), p<0.001), with no interaction by ethnicity. Conclusion We found ethnic differences in the association between EF and QRSd among patients with HF. QRS prolongation was similarly associated with increased risk, but the implications for ethnicity-specific QRSd cut-offs in clinical decision-making require further study. PMID:27402805

  17. Adaptive Rule Based Fetal QRS Complex Detection Using Hilbert Transform

    PubMed Central

    Ulusar, Umit D.; Govindan, R.B.; Wilson, James D.; Lowery, Curtis L.; Preissl, Hubert; Eswaran, Hari

    2010-01-01

    In this paper we introduce an adaptive rule based QRS detection algorithm using the Hilbert transform (adHQRS) for fetal magnetocardiography processing. Hilbert transform is used to combine multiple channel measurements and the adaptive rule based decision process is used to eliminate spurious beats. The algorithm has been tested with a large number of datasets and promising results were obtained. PMID:19964648

  18. Electrocardiogram Derived QRS Duration >120 ms is Associated With Elevated Plasma Homocysteine Levels in a Rural Australian Cross-Sectional Population

    PubMed Central

    Leng, Yvonne Lee Yin; Zhou, Yuling; Ke, Honghong; Jelinek, Herbert; McCabe, Joel; Assareh, Hassan; McLachlan, Craig S.

    2015-01-01

    Abstract Homocysteine levels in the low to moderate range for cardiovascular risk have been previously associated with left ventricular cardiac hypertrophy (LVH). Electrocardiogram (ECG) derived QRS duration has also been used as an epidemiological screening marker for cardiac hypertrophy risk. QRS duration cut offs have not been previously modeled to assess homocysteine levels in community populations. Our aims are to determine if QRS duration is associated with an elevated homocysteine level in a cross-sectional Australian aging rural population. A retrospective study design utilizing a rural health diabetic screening clinic database containing observational data from the period January 9, 2002 till September 25, 2012. One hundred seventy-eight individuals (>21 years of age) from the database were included in the study. Inclusion criteria included being nondiabetic and having both a QRS duration measure and a matching homocysteine level within the same subject. All participants were from the Albury-Wodonga area, with a mean age of >64 years for both sexes. Mean population homocysteine plasma levels were 10.4 μmol/L (SD = 3.6). The mean QRS duration was 101.8 ms (SD = 17.4). Groups were stratified on the basis of QRS duration (≤120 ms [n = 157] and >120 ms [n = 21]). QRS duration subgroup (≤120 ms vs >120 ms) mean differences across homocysteine levels were 10.1 μmol/L (SD = 3.3) and 12.2 μmol/L (SD = 4.7), respectively (P = 0.016). Other ECG parameters (PQ interval, QTc interval, and QT dispersion) measurements were not significantly associated with differences in plasma homocysteine (P = not significant). We conclude that in community populations homocysteine may be moderately elevated when QRS durations are >120 ms. Small additional increases in homocysteine levels may suggest a risk factor for ECG diagnosis of LVH. PMID:26166085

  19. QRS duration: a novel marker of microvascular reperfusion as assessed by myocardial blush grade in ST elevation myocardial infarction patients undergoing a primary percutaneous intervention

    PubMed Central

    Yaylak, Bariş; Uğurlu, Murat; Kaya, İlyas; Uçaman, Berzal; Öztürk, Önder

    2015-01-01

    Objectives Prolonged QRS duration is a predictor of poor prognosis in patients with coronary artery disease. The association between the duration of QRS and myocardial reperfusion is not very well understood. Our aim was to assess the relationship between the measurements of QRS duration and myocardial blush grade (MBG) in patients with ST elevation myocardial infarction (STEMI) who were treated with a primary percutaneous intervention. Patients and methods A total of 213 patients (mean age: 57.5±11 years) with STEMI were included. ECG recordings were obtained for the evaluation of the QRS duration before and after primary percutaneous coronary intervention. Angiographic assessment in the infarct-related artery was performed using the MBG. Patients were categorized into two groups of those with impaired microvascular reperfusion (MBG: 0–1) and those with normal microvascular reperfusion (MBG: 2–3). Results Overall, 105 and 108 patients had an MBG of 0–1 or 2–3, respectively. There is no significant difference between patient’s characteristics. Despite the absence of a difference between two groups in terms of the QRS duration at presentation (P: 0.57), patients with impaired microvascular reperfusion were found to have longer QRS duration at immediately postprocedure (P: 0.003) and postprocedure 60 min time-points (P<0.001). Correlation analyses showed a positive correlation between pain-to-balloon time and QRS duration at postprocedure 60 min time-points (r: 0.137 and P: 0.04). Conclusion Our results suggest that longer QRS duration after angioplasty seemed to indicate the presence of impaired microvascular reperfusion in patients with STEMI. PMID:26166018

  20. A novel low-complexity post-processing algorithm for precise QRS localization.

    PubMed

    Fonseca, Pedro; Aarts, Ronald M; Foussier, Jérôme; Long, Xi

    2014-01-01

    Precise localization of QRS complexes is an essential step in the analysis of small transient changes in instant heart rate and before signal averaging in QRS morphological analysis. Most localization algorithms reported in literature are either not robust to artifacts, depend on the sampling rate of the ECG recordings or are too computationally expensive for real-time applications, especially in low-power embedded devices. This paper proposes a localization algorithm based on the intersection of tangents fitted to the slopes of R waves detected by any QRS detector. Despite having a lower complexity, this algorithm achieves comparable trigger jitter to more complex localization methods without requiring the data to first be upsampled. It also achieves high localization precision regardless of which QRS detector is used as input. It is robust to clipping artifacts and to noise, achieving an average localization error below 2 ms and a trigger jitter below 1 ms on recordings where no additional artifacts were added, and below 8 ms for recordings where the signal was severely degraded. Finally, it increases the accuracy of template-based false positive rejection, allowing nearly all mock false positives added to a set of QRS detections to be removed at the cost of a very small decrease in sensitivity. The localization algorithm proposed is particularly well-suited for implementation in embedded, low-power devices for real-time applications. PMID:26034664

  1. A novel low-complexity post-processing algorithm for precise QRS localization.

    PubMed

    Fonseca, Pedro; Aarts, Ronald M; Foussier, Jérôme; Long, Xi

    2014-01-01

    Precise localization of QRS complexes is an essential step in the analysis of small transient changes in instant heart rate and before signal averaging in QRS morphological analysis. Most localization algorithms reported in literature are either not robust to artifacts, depend on the sampling rate of the ECG recordings or are too computationally expensive for real-time applications, especially in low-power embedded devices. This paper proposes a localization algorithm based on the intersection of tangents fitted to the slopes of R waves detected by any QRS detector. Despite having a lower complexity, this algorithm achieves comparable trigger jitter to more complex localization methods without requiring the data to first be upsampled. It also achieves high localization precision regardless of which QRS detector is used as input. It is robust to clipping artifacts and to noise, achieving an average localization error below 2 ms and a trigger jitter below 1 ms on recordings where no additional artifacts were added, and below 8 ms for recordings where the signal was severely degraded. Finally, it increases the accuracy of template-based false positive rejection, allowing nearly all mock false positives added to a set of QRS detections to be removed at the cost of a very small decrease in sensitivity. The localization algorithm proposed is particularly well-suited for implementation in embedded, low-power devices for real-time applications.

  2. ECG series. Narrow QRS-complex tachycardia: Part 2

    PubMed Central

    Singh, Devinder; Teo, Swee-Guan; Omar, Abdul Razakjr Bin; Poh, Kian-Keong

    2014-01-01

    We discuss two cases of incessant atrial tachycardia (AT), including the presentation and clinical course. It is important to differentiate AT from other causes of supraventricular tachycardia, such as atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular reentrant tachycardia (AVRT), as it would have implications on clinical management. Electrocardiographic features of AT, especially the presence of an AV Wenckebach phenomenon with ‘grouped beating’, are critical for differentiating AT from AVRT and AVNRT. It is also vital to identify the P waves and their relations to QRS on electrocardiography, as this would aid in the differentiation of various supraventricular tachycardias. PMID:25273927

  3. Electrocardiography series. Narrow QRS-complex tachycardia: part 2.

    PubMed

    Singh, Devinder; Teo, Swee-Guan; Omar, Abdul Razakjr Bin; Poh, Kian Keong

    2014-09-01

    We discuss two cases of incessant atrial tachycardia (AT), including the presentation and clinical course. It is important to differentiate AT from other causes of supraventricular tachycardia, such as atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular reentrant tachycardia (AVRT), as it would have implications on clinical management. Electrocardiographic features of AT, especially the presence of an AV Wenckebach phenomenon with 'grouped beating', are critical for differentiating AT from AVRT and AVNRT. It is also vital to identify the P waves and their relations to QRS on electrocardiography, as this would aid in the differentiation of various supraventricular tachycardias.

  4. Simultaneous wide and narrow QRS complex tachycardia: what is the mechanism?

    PubMed

    Rodríguez-Mañero, Moisés; Bayrak, Fatih; Namdar, Mehdi; Casado-Arroyo, Rubén; Ricciardi, Danilo; Chierchia, Gian-Battista; Sarkozy, Andrea; de Asmundis, Carlo; Brugada, Pedro

    2013-05-01

    We present the case of a 50-year-old patient with several episodes of syncope and documented simultaneous wide and narrow QRS complex tachycardia. We then review this tacharrhythmia, focusing on electrophysiological findings and pathophysiology, diagnosis and treatment. PMID:23688775

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

    PubMed

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

    2014-08-01

    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.

  6. Data fusion for QRS complex detection in multi-lead electrocardiogram recordings

    NASA Astrophysics Data System (ADS)

    Ledezma, Carlos A.; Perpiñan, Gilberto; Severeyn, Erika; Altuve, Miguel

    2015-12-01

    Heart diseases are the main cause of death worldwide. The first step in the diagnose of these diseases is the analysis of the electrocardiographic (ECG) signal. In turn, the ECG analysis begins with the detection of the QRS complex, which is the one with the most energy in the cardiac cycle. Numerous methods have been proposed in the bibliography for QRS complex detection, but few authors have analyzed the possibility of taking advantage of the information redundancy present in multiple ECG leads (simultaneously acquired) to produce accurate QRS detection. In our previous work we presented such an approach, proposing various data fusion techniques to combine the detections made by an algorithm on multiple ECG leads. In this paper we present further studies that show the advantages of this multi-lead detection approach, analyzing how many leads are necessary in order to observe an improvement in the detection performance. A well known QRS detection algorithm was used to test the fusion techniques on the St. Petersburg Institute of Cardiological Technics database. Results show improvement in the detection performance with as little as three leads, but the reliability of these results becomes interesting only after using seven or more leads. Results were evaluated using the detection error rate (DER). The multi-lead detection approach allows an improvement from DER = 3:04% to DER = 1:88%. Further works are to be made in order to improve the detection performance by implementing further fusion steps.

  7. Combining algorithms in automatic detection of QRS complexes in ECG signals.

    PubMed

    Meyer, Carsten; Fernández Gavela, José; Harris, Matthew

    2006-07-01

    QRS complex and specifically R-Peak detection is the crucial first step in every automatic electrocardiogram analysis. Much work has been carried out in this field, using various methods ranging from filtering and threshold methods, through wavelet methods, to neural networks and others. Performance is generally good, but each method has situations where it fails. In this paper, we suggest an approach to automatically combine different QRS complex detection algorithms, here the Pan-Tompkins and wavelet algorithms, to benefit from the strengths of both methods. In particular, we introduce parameters allowing to balance the contribution of the individual algorithms; these parameters are estimated in a data-driven way. Experimental results and analysis are provided on the Massachusetts Institute of Technology-Beth Israel Hospital (MIT-BIH) Arrhythmia Database. We show that our combination approach outperforms both individual algorithms. PMID:16871713

  8. The ability of mitral papillary muscle positions to explain QRS complex characteristics in humans.

    PubMed

    Hakacova, Nina

    2016-01-01

    Anatomical location of the conduction system may influence the characteristics of the depolarization and thus characteristics of the QRS complex. It is known that in the heart, there are electro-anatomical relationships, such as relationships among the molecular, genetic and anatomic components of the conduction system and papillary muscles. This review aims to discuss how knowledge of the electro-anatomical developmental relationships helps in understanding the known variability to be observed in the human electrocardiograms. PMID:27477762

  9. A FPGA system for QRS complex detection based on Integer Wavelet Transform

    NASA Astrophysics Data System (ADS)

    Stojanović, R.; Karadaglić, D.; Mirković, M.; Milošević, D.

    2011-01-01

    Due to complexity of their mathematical computation, many QRS detectors are implemented in software and cannot operate in real time. The paper presents a real-time hardware based solution for this task. To filter ECG signal and to extract QRS complex it employs the Integer Wavelet Transform. The system includes several components and is incorporated in a single FPGA chip what makes it suitable for direct embedding in medical instruments or wearable health care devices. It has sufficient accuracy (about 95%), showing remarkable noise immunity and low cost. Additionally, each system component is composed of several identical blocks/cells what makes the design highly generic. The capacity of today existing FPGAs allows even dozens of detectors to be placed in a single chip. After the theoretical introduction of wavelets and the review of their application in QRS detection, it will be shown how some basic wavelets can be optimized for easy hardware implementation. For this purpose the migration to the integer arithmetic and additional simplifications in calculations has to be done. Further, the system architecture will be presented with the demonstrations in both, software simulation and real testing. At the end, the working performances and preliminary results will be outlined and discussed. The same principle can be applied with other signals where the hardware implementation of wavelet transform can be of benefit.

  10. Investigation of connexin 43 uncoupling and prolongation of the cardiac QRS complex in preclinical and marketed drugs

    PubMed Central

    Burnham, M P; Sharpe, P M; Garner, C; Hughes, R; Pollard, C E; Bowes, J

    2014-01-01

    Background and Purpose Prolongation of the cardiac QRS complex is linked to increased mortality and may result from drug-induced inhibition of cardiac sodium channels (hNaV1.5). There has been no systematic evaluation of preclinical and marketed drugs for their additional potential to cause QRS prolongation via gap junction uncoupling. Experimental Approach Using the human cardiac gap junction connexin 43 (hCx43), a dye transfer ‘parachute’ assay to determine IC50 values for compound ranking was validated with compounds known to uncouple gap junctions. Uncoupling activity (and hNaV1.5 inhibition by automated patch clamp) was determined in a set of marketed drugs and preclinical candidate drugs, each with information regarding propensity to prolong QRS. Key Results The potency of known gap junction uncouplers to uncouple hCx43 was ranked (according to IC50) as phorbol ester>digoxin>meclofenamic acid>carbenoxolone>heptanol. Among the drugs associated with QRS prolongation, 29% were found to uncouple hCx43 (IC50 < 50 μM), whereas no uncoupling activity was observed in drugs not associated with QRS prolongation. In preclinical candidate drugs, hCx43 and hNaV1.5 IC50 values were similar (within threefold). No consistent margin over preclinical Cmax (free) was apparent for QRS prolongation associated with Cx43 inhibition. However, instances were found of QRS prolonging compounds that uncoupled hCx43 with significantly less activity at hNaV1.5. Conclusion and Implications These results demonstrate that off-target uncoupling activity is apparent in drug and drug-like molecules. Although the full ramifications of Cx inhibition remain to be established, screening for hCx43 off-target activity could reduce the likelihood of developing candidate drugs with a risk of causing QRS prolongation. PMID:24328991

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

    PubMed

    Hoseini Sabzevari, S A; Moavenian, Majid

    2014-01-01

    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

  12. A consensus algorithm for approximate string matching and its application to QRS complex detection

    NASA Astrophysics Data System (ADS)

    Alba, Alfonso; Mendez, Martin O.; Rubio-Rincon, Miguel E.; Arce-Santana, Edgar R.

    2016-08-01

    In this paper, a novel algorithm for approximate string matching (ASM) is proposed. The novelty resides in the fact that, unlike most other methods, the proposed algorithm is not based on the Hamming or Levenshtein distances, but instead computes a score for each symbol in the search text based on a consensus measure. Those symbols with sufficiently high scores will likely correspond to approximate instances of the pattern string. To demonstrate the usefulness of the proposed method, it has been applied to the detection of QRS complexes in electrocardiographic signals with competitive results when compared against the classic Pan-Tompkins (PT) algorithm. The proposed method outperformed PT in 72% of the test cases, with no extra computational cost.

  13. Association of fragmented QRS complex with myocardial reperfusion in acute ST-elevated myocardial infarction.

    PubMed

    Erdem, Fatma Hizal; Tavil, Yusuf; Yazici, Hüseyin; Aygül, Nazif; Abaci, Adnan; Boyaci, Bülent

    2013-01-01

    In this study, we aimed to evaluate the relationship between TIMI myocardial perfusion (TMP) grade, as an indicator of myocardial reperfusion, and fragmented QRS (fQRS) in standard 12-lead electrocardiogram. Also, we evaluate fQRS is an additional indicator of myocardial reperfusion. One hundred patients admitted with first STEMI to Coronary Intensive Care Unit and who were used thrombolytic therapy was included in this retrospective study. Standard 12-lead electrocardiogram records of patients simultaneous with coronary angiography (second day) were assessed and analysed for the presence of fQRS. Also, coronary angiography images were analyzed to identify the infarct related artery, TIMI grade of infarct related artery and TMP grade of infarct related artery. The patients with fQRS demonstrated a significantly lower TMP grade, TIMI grade and ejection fraction compared with the non-fQRS patients (P = 0.004, P = 0.003, P = 0.02 respectively). The patients with inadequate myocardial reperfusion demonstrated a significantly higher fQRS compared with the adequate myocardial reperfusion patients. (56.9% versus 23.5%, P = 0.002 respectively). On correlation analysis, there was a significant negative correlation between fQRS and left ventricular ejection fraction (r = -232, P = 0.02) TMP grade and adequate myocardial reperfusion (TMP 3) showed significant negative correlation with fQRS (r = -0.370, P = 0.000; r = -0.318, P = 0.001 respectively). Presence of fragmented QRS in STEMI patients was associated with inadequate myocardial reperfusion and it can be used as a simple, noninvasive parameter to evaluate myocardial reperfusion.

  14. Paced QRS duration and myocardial scar amount: predictors of long-term outcome of right ventricular apical pacing.

    PubMed

    Lee, Seung-Ah; Cha, Myung-Jin; Cho, Youngjin; Oh, Il-Young; Choi, Eue-Keun; Oh, Seil

    2016-07-01

    Long-term right ventricular apical pacing (RVAP) is reportedly associated with heart failure (HF) development. However, the predictors of pacing-induced HF (PHF) remained unclear. We retrospectively enrolled 234 patients without structural heart disease who underwent a permanent pacemaker implantation with RVAP between 1982 and 2004. RVAP-induced HF was defined as left ventricular ejection fraction decrease >5 % with HF symptom without other HF development etiology. The QRS duration of a paced beat (pQRSd) and myocardial scar score were analyzed from each patient's 12-lead ECG. During a mean 15.6 years (range 3.3-30.0 years), 48 patients (20.5 %) patients developed RVAP-induced HF. The PHF group patients had a longer pQRSd (192.4 ± 13.5 vs. 175.7 ± 14.7 ms in non-PHF patients, p < 0.001) and a higher myocardial scar score (5.2 ± 1.9 vs. 2.7 ± 1.9, respectively p < 0.001). In multivariate Cox regression analysis, old age at implantation [Hazard ratio (HR) 1.62, 95 % confidential interval (CI) 1.22-2.16, p = 0.001], a longer pQRSd (HR 1.54, 95 % CI 1.15-2.05, p = 0.003), a higher myocardial scar score (HR 1.23, 95 % CI 1.03-1.49, p = 0.037), and a higher percentage of ventricular pacing (HR 1.31, 95 % CI 1.01-1.49, p = 0.010) were independent predictors of PHF. Based on the results of the receiver-operating characteristic (ROC) curve, the pQRSd cutoff was 185 ms (AUC 0.79, sensitivity 66.7 %, specificity 76.3 %) and myocardial scar score cutoff value was 4 (AUC 0.81, sensitivity 81.3 %, specificity 66.1 %). The pQRSd was positively correlated with scar score (r = 0.70, p < 0.001). pQRSd ≥185 ms and/or myocardial scar score ≥4 might be independent long-term prognostic markers of PHF.

  15. [Supraventricular tachycardia with wide QRS complexes during Vaughan-Williams class I anti-arrhythmic treatment. Diagnostic and therapeutic implications].

    PubMed

    Aouate, P; Frank, R; Fontaine, G; Tonet, J; Tageddine, R; Benassar, A; Turlure, A; Jacquemin, M; Laborde, J P

    1995-12-01

    The authors report 8 cases of regular tachycardia with wide QRS complexes during treatment with Vaughan-Williams class 1 antiarrhythmic drugs. These antiarrhythmics, prescribed to prevent atrial fibrillation (3 patients) and atrial flutter (5 patients), were flecainide in 4 cases, propafenone in 2 cases and cibenzoline and hydroquinidine respectively associated with digitoxine and propranolol. These wide complex tachycardias were regular atrial tachycardias with 1/1 conduction to the ventricle. The action of the drug, more pronounced on intra-atrial conduction velocities than on atrioventricular node refractoriness resulted in transformation of flutter at 300 cycles/min with 2/1 conduction and a ventricular rate of 150 cycles/min to atrial flutter at 210 cycles/min with 1/1 ventricular conduction. This acceleration of the ventricular rate was accompanied by widening of the QRS complex. Using the new ventricular tachycardia criteria recently published by Brugada resulted in a diagnostic error in 7 out of the 8 cases. The recording of a wide QRS complex tachycardia in a patient on class 1 antiarrhythmic therapy for an atrial arrhythmia should alert the physician to 1/1 atrial tachycardia despite morphological electrocardiographic criteria of ventricular tachycardia. The 1/1 atrial tachycardia may be poorly tolerated and require emergency treatment. The preventive association of a drug which slows conduction through the atrioventricular node is not always effective.

  16. Quick detection of QRS complexes and R-waves using a wavelet transform and K-means clustering.

    PubMed

    Xia, Yong; Han, Junze; Wang, Kuanquan

    2015-01-01

    Based on the idea of telemedicine, 24-hour uninterrupted monitoring on electrocardiograms (ECG) has started to be implemented. To create an intelligent ECG monitoring system, an efficient and quick detection algorithm for the characteristic waveforms is needed. This paper aims to give a quick and effective method for detecting QRS-complexes and R-waves in ECGs. The real ECG signal from the MIT-BIH Arrhythmia Database is used for the performance evaluation. The method proposed combined a wavelet transform and the K-means clustering algorithm. A wavelet transform is adopted in the data analysis and preprocessing. Then, based on the slope information of the filtered data, a segmented K-means clustering method is adopted to detect the QRS region. Detection of the R-peak is based on comparing the local amplitudes in each QRS region, which is different from other approaches, and the time cost of R-wave detection is reduced. Of the tested 8 records (total 18201 beats) from the MIT-BIH Arrhythmia Database, an average R-peak detection sensitivity of 99.72 and a positive predictive value of 99.80% are gained; the average time consumed detecting a 30-min original signal is 5.78s, which is competitive with other methods. PMID:26405862

  17. Stream computing for biomedical signal processing: A QRS complex detection case-study.

    PubMed

    Murphy, B M; O'Driscoll, C; Boylan, G B; Lightbody, G; Marnane, W P

    2015-01-01

    Recent developments in "Big Data" have brought significant gains in the ability to process large amounts of data on commodity server hardware. Stream computing is a relatively new paradigm in this area, addressing the need to process data in real time with very low latency. While this approach has been developed for dealing with large scale data from the world of business, security and finance, there is a natural overlap with clinical needs for physiological signal processing. In this work we present a case study of streams processing applied to a typical physiological signal processing problem: QRS detection from ECG data. PMID:26737641

  18. Stream computing for biomedical signal processing: A QRS complex detection case-study.

    PubMed

    Murphy, B M; O'Driscoll, C; Boylan, G B; Lightbody, G; Marnane, W P

    2015-01-01

    Recent developments in "Big Data" have brought significant gains in the ability to process large amounts of data on commodity server hardware. Stream computing is a relatively new paradigm in this area, addressing the need to process data in real time with very low latency. While this approach has been developed for dealing with large scale data from the world of business, security and finance, there is a natural overlap with clinical needs for physiological signal processing. In this work we present a case study of streams processing applied to a typical physiological signal processing problem: QRS detection from ECG data.

  19. Ventricular Tachycardia or not? An Unexpected Reason of Wide QRS Complex Tachycardia in a Young Healthy Man: Sodium Bicarbonate.

    PubMed

    Eyuboglu, Mehmet

    2016-10-01

    Ventricular tachycardia (VT) is life-threatening subgroup of wide QRS complex tachycardia (WCT). VT is usually associated with structural heart diseases, but it can occur in the absence of any cardiovascular diseases. Adverse cardiac effect of sodium bicarbonate in healthy subjects is not well described. A 30-year-old healthy man with excessive intake of sodium bicarbonate-related VT is presented. He was using sodium bicarbonate during last 2 months to lose weight. He has no risk factors and any cardiovascular or systemic diseases. After intravenous administration of amiodarone, tachycardia ended and his rhythm converted to sinus rhythm with normal electrocardiogram. Patient is asymptomatic, and no VT was observed without any medications at 1 year of follow-up.

  20. [Cardiac contractility modulation. A new form of therapy for patients with heart failure and narrow QRS complex?].

    PubMed

    Kleemann, T

    2015-11-01

    Cardiac contractility modulation (CCM) is a stimulation therapy by an implantable impulse generator, which enhances ventricular contractile performance by delivering CCM impulses to the right ventricle during the absolute refractory period. The CCM signals mediate increased inotropy by prolonging the duration of the action potential, which leads to an enhanced influx of calcium into cardiomyocytes and a greater release of calcium by the sarcoplasmic reticulum. The increase of cardiac contractility is not associated with increased oxygen consumption. Several small studies have shown that CCM therapy can safely improve symptoms of heart failure and peak oxygen consumption in patients with moderate to severe heart failure who are not eligible for resynchronization therapy. Therefore, CCM is a novel potential therapy for patients with heart failure, an ejection fraction ≤ 35 % and a normal QRS duration < 130 ms. However, apart from selecting appropriate patients for CCM therapy there are still unanswered questions, such as the impact of CCM therapy on established clinical endpoints. At present no data are available which have shown that CCM therapy leads to reduction of hospitalization for heart failure or mortality.

  1. Prolonged QRS Duration on the Resting ECG is Associated with Sudden Death Risk in Coronary Disease, Independent of Prolonged Ventricular Repolarization

    PubMed Central

    Teodorescu, C; Reinier, K; Uy-Evanado, A; Navarro, J; Mariani, R; Gunson, K; Jui, J; Chugh, SS

    2011-01-01

    Background Abnormalities of ventricular repolarization as well as depolarization have been associated with increased risk of ventricular arrhythmias. Objective We evaluated the relative contribution of these predictors to risk of sudden cardiac death (SCD) among patients with coronary artery disease (CAD). Methods In the ongoing Oregon Sudden Unexpected Death Study (Oregon SUDS), adult residents of Portland, OR metropolitan area (population ~1 million) who suffered SCD were identified prospectively (2002-2007). Of these, we analyzed the subgroup of SCDs that had a resting 12-lead ECG prior to SCD and also had associated CAD. Comparisons were conducted with a control group of subjects with known CAD, but no history of SCD from the same geographic region. Corrected QT interval (QTc), JT interval (JTc), QRS duration (QRSd) and other parameters were measured from ECG prior and unrelated to SCD. Analysis of LV function was limited to those subjects that had echocardiography performed prior to and remote from SCD. Results A total of 642 SCD cases (71±13 yrs, 62% male) were compared to 450 controls (66±12 yrs, 64% male). SCD cases had significantly longer QRSd (102±25 vs. 97±20 ms, p=0.0008) as well as JTc (348±44 vs. 339±34 ms, p=0.0006) vs. controls. In cases with prolonged QRSd, 38% had severe LV systolic dysfunction (LVSD) and 62% had normal, mild or moderately decreased LV systolic function. In a multivariable model, QRSd, JTc, age and severe LVSD were independent predictors. There was minimal overlap between prolonged QRSd and JTc in both case and control groups (3% and 4%, respectively). Conclusions Prolonged QRSd, JTc and severe LVSD had independent contributions to risk of SCD in coronary disease, in this community-based setting. PMID:21699869

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

    PubMed

    Scher, A M

    1995-01-01

    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

  3. 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

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

    2014-01-01

    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

  4. High Frequency QRS ECG Accurately Detects Cardiomyopathy

    NASA Technical Reports Server (NTRS)

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

    2005-01-01

    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

  5. Magnetocardiographic intra-QRS fragmentation analysis in the identification of patients with sustained ventricular tachycardia after myocardial infarction.

    PubMed

    Korhonen, P; Montonen, J; Endt, P; Mäkijärvi, M; Trahms, L; Katila, T; Toivonen, L

    2001-08-01

    The aim of this study was to investigate if magnetocardiographic (MCG) analysis of cardiac micropotentials within the QRS complex can identity patients prone to ventricular arrhythmias, and to compare it to MCG time-domain, late-field analysis. The study population consisted of 136 patients with remote MI, 53 with and 83 without a history of VT. After averaging and high pass filtering of multichannel MCG signals, time-domain parameters describing the end-QRS activity and fragmentation index M and score S describing the whole QRS complex were computed. Fragmentation and time-domain parameters differed between the VT and control groups: fragmentation index M was 12 +/- 3 versus 9 +/- 2 (P <0.001), fragmentation score S was 83 +/- 42 versus 56 +/- 21 (P < 0.001), and filtered QRS duration was 144 +/- 32 versus 114 +/- 19 ms (P < 0.001) in VT and control groups, respectively. A combination of fragmentation parameters yielded 87% sensitivity and 61% specificity in VT identification. Corresponding figures for a time-domain parameter combination were 81% and 72%. Sensitivity of time-domain analysis was 88% and specificity was 75% in a subgroup with anterior MI. In multivariate analysis, fragmentation and time-domain analyses discriminated VT patients from controls independently of the extent of coronary artery disease or left ventricular dysfunction. MCG in postinfarction patients reveals pathology associated with propensity to ventricular arrhythmias inside and not only at the end of the QRS complex. MCG seems most accurate in the anterior infarct location.

  6. Relation of fragmented QRS complex to right ventricular fibrosis detected by late gadolinium enhancement cardiac magnetic resonance in adults with repaired tetralogy of fallot.

    PubMed

    Park, Seung-Jung; On, Young Keun; Kim, June Soo; Park, Seung Woo; Yang, Ji-Hyuk; Jun, Tae-Gook; Kang, I-Seok; Lee, Heung Jae; Choe, Yeon Hyeon; Huh, June

    2012-01-01

    Fragmented QRS (fQRS) on 12-lead electrocardiography reflects conduction delay caused by myocardial fibrosis and dysfunction. Ventricular fibrosis detected by late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) is reportedly correlated with worse clinical outcomes in adults with repaired tetralogy of Fallot (TOF). The aim of this study was to assess whether the presence of fQRS is associated with right ventricular (RV) fibrosis or dysfunction in this patient group. In 37 consecutive patients (median age 30 years, median age at repair 6.6 years), the number of leads showing fQRS, defined as the presence of >2 notches on the R/S wave in ≥2 contiguous leads, was counted. RV systolic function, dilatation, and LGE score were measured using LGE CMR. Ventricular LGE was observed mainly at the previous surgical sites: the RV outflow tract (33 of 37), ventricular septal defect patch region (15 of 37), and RV anterior wall (11 of 37). Fragmented QRS was found mostly in the right and mid precordial leads. The fQRS group (n = 20) demonstrated higher RV LGE scores (p <0.001) and lower RV ejection fractions (p = 0.02) and a trend toward larger RV end-diastolic and end-systolic volumes (p = 0.12 and p = 0.06, respectively) compared to the non-fQRS group (n = 17). The number of electrocardiographic leads showing fQRS was positively correlated with RV LGE score (r = 0.75, p <0.001). The presence of fQRS remained independently associated with the presence of supramedian RV LGE score, even after adjusting for relevant parameters. In conclusion, fQRS was closely associated with more extensive RV fibrosis and dysfunction in adults with repaired tetralogy of Fallot.

  7. A PD control-based QRS detection algorithm for wearable ECG applications.

    PubMed

    Choi, Changmok; Kim, Younho; Shin, Kunsoo

    2012-01-01

    We present a QRS detection algorithm for wearable ECG applications using a proportional-derivative (PD) control. ECG data of arrhythmia have irregular intervals and magnitudes of QRS waves that impede correct QRS detection. To resolve the problem, PD control is applied to avoid missing a small QRS wave followed from a large QRS wave and to avoid falsely detecting noise as QRS waves when an interval between two adjacent QRS waves is large (e.g. bradycardia, pause, and arioventricular block). ECG data was obtained from 78 patients with various cardiovascular diseases and tested for the performance evaluation of the proposed algorithm. The overall sensitivity and positive predictive value were 99.28% and 99.26%, respectively. The proposed algorithm has low computational complexity, so that it can be suitable to apply mobile ECG monitoring system in real time. PMID:23367208

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

    PubMed Central

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

    2013-01-01

    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

  9. Real-time, high frequency QRS electrocardiograph

    NASA Technical Reports Server (NTRS)

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

    2006-01-01

    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.

  10. A computationally efficient QRS detection algorithm for wearable ECG sensors.

    PubMed

    Wang, Y; Deepu, C J; Lian, Y

    2011-01-01

    In this paper we present a novel Dual-Slope QRS detection algorithm with low computational complexity, suitable for wearable ECG devices. The Dual-Slope algorithm calculates the slopes on both sides of a peak in the ECG signal; And based on these slopes, three criterions are developed for simultaneously checking 1)Steepness 2)Shape and 3)Height of the signal, to locate the QRS complex. The algorithm, evaluated against MIT/BIH Arrhythmia Database, achieves a very high detection rate of 99.45%, a sensitivity of 99.82% and a positive prediction of 99.63%. PMID:22255619

  11. The Spatial QRS-T Angle: Implications in Clinical Practice

    PubMed Central

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

    2013-01-01

    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

  12. The relation of QRS amplitude to the frontal QRS axis and the heart-electrode distance.

    NASA Technical Reports Server (NTRS)

    Dougherty, J. D.

    1971-01-01

    The relation between QRS amplitude, QRS axis deviation and heart position was studied in 360 subjects, using the 12-lead EKG. The height of the V sub 6 R wave was used as the measure of QRS amplitude. The distance from the left lateral border of the heart was used to indicate heart position. The frontal and horizontal QRS axes were determined by noting the isoelectric limb and precordial leads, measured according to Schmitt's values.

  13. Effects of presentation duration on measures of complexity in affective environmental scenes and representational paintings.

    PubMed

    Marin, Manuela M; Leder, Helmut

    2016-01-01

    Complexity constitutes an integral part of humans' environment and is inherent to information processing. However, little is known about the dynamics of visual complexity perception of affective environmental scenes (IAPS pictures) and artworks, such as affective representational paintings. In three experiments, we studied the time course of visual complexity perception by varying presentation duration and comparing subjective ratings with objective measures of complexity. In Experiment 1, 60 females rated 96 IAPS pictures, presented either for 1, 5, or 25s, for familiarity, complexity, pleasantness and arousal. In Experiment 2, another 60 females rated 96 representational paintings. Mean ratings of complexity and pleasantness changed according to presentation duration in a similar vein in both experiments, suggesting an inverted U-shape. No common pattern of results was observed for arousal and familiarity ratings across the two picture sets. The correlations between subjective and objective measures of complexity increased with longer exposure durations for IAPS pictures, but results were more ambiguous for paintings. Experiment 3 explored the time course of the multidimensionality of visual complexity perception. Another 109 females rated the number of objects, their disorganization and the differentiation between a figure-ground vs. complex scene composition of pictures presented for 1 and 5s. The multidimensionality of visual complexity only clearly emerged in the 5-s condition. In both picture sets, the strength of the correlations with objective measures depended on the type of subdimension of complexity and was less affected by presentation duration than correlations with general complexity in Experiments 1 and 2. These results have clear implications for perceptual and cognitive theories, especially for those of esthetic experiences, in which the dynamical changes of complexity perception need to be integrated. PMID:26595281

  14. Effects of presentation duration on measures of complexity in affective environmental scenes and representational paintings.

    PubMed

    Marin, Manuela M; Leder, Helmut

    2016-01-01

    Complexity constitutes an integral part of humans' environment and is inherent to information processing. However, little is known about the dynamics of visual complexity perception of affective environmental scenes (IAPS pictures) and artworks, such as affective representational paintings. In three experiments, we studied the time course of visual complexity perception by varying presentation duration and comparing subjective ratings with objective measures of complexity. In Experiment 1, 60 females rated 96 IAPS pictures, presented either for 1, 5, or 25s, for familiarity, complexity, pleasantness and arousal. In Experiment 2, another 60 females rated 96 representational paintings. Mean ratings of complexity and pleasantness changed according to presentation duration in a similar vein in both experiments, suggesting an inverted U-shape. No common pattern of results was observed for arousal and familiarity ratings across the two picture sets. The correlations between subjective and objective measures of complexity increased with longer exposure durations for IAPS pictures, but results were more ambiguous for paintings. Experiment 3 explored the time course of the multidimensionality of visual complexity perception. Another 109 females rated the number of objects, their disorganization and the differentiation between a figure-ground vs. complex scene composition of pictures presented for 1 and 5s. The multidimensionality of visual complexity only clearly emerged in the 5-s condition. In both picture sets, the strength of the correlations with objective measures depended on the type of subdimension of complexity and was less affected by presentation duration than correlations with general complexity in Experiments 1 and 2. These results have clear implications for perceptual and cognitive theories, especially for those of esthetic experiences, in which the dynamical changes of complexity perception need to be integrated.

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

    PubMed

    Saini, Indu; Singh, Dilbag; Khosla, Arun

    2013-07-01

    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.

  16. The Development of Mental Models for Auditory Events: Relational Complexity and Discrimination of Pitch and Duration

    ERIC Educational Resources Information Center

    Stevens, Catherine; Gallagher, Melinda

    2004-01-01

    This experiment investigated relational complexity and relational shift in judgments of auditory patterns. Pitch and duration values were used to construct two-note perceptually similar sequences (unary relations) and four-note relationally similar sequences (binary relations). It was hypothesized that 5-, 8- and 11-year-old children would perform…

  17. Using QRS morphology and QTc interval to prevent complications and cardiac death.

    PubMed

    Attin, Mina; Davidson, Judy E

    2011-01-01

    Prevention of cardiac complications including death is influenced by the availability of diagnostic tools and technological advances. Cardiac telemetry as a diagnostic tool is widely used in hospitals because of an increased severity of illness and complex modality of treatments. QTc interval abnormalities in the electrocardiogram have been long recognized as a predictive precursor for life-threatening cardiac arrhythmias and cardiac arrest. QRS morphology has also been recognized as a reliable marker to prevent cardiac events in outpatient settings. However, the QTc and QRS morphology as electrocardiogram predictors are not routinely assessed in daily practice for hospitalized patients because of the slow advancement of technology in bedside monitoring systems and inadequate staff preparation. This article discusses the role of QRS morphology and QTc interval assessment in predicting risk of complications. The article also explores the need for further research and advancement in technology to overcome barriers to integrating these predictors into routine nursing practice.

  18. Differential diagnosis of wide QRS tachycardias.

    PubMed

    Lobban, J H; Schmidt, S B; Rhodes, L A; Jain, A C

    1994-06-01

    This article has reviewed the differential diagnosis of wide QRS tachycardia. We have found the stepwise approach suggested by Brugada to be very useful. Of the newer criteria that he proposes, the R to S interval of > 100 ms. appears to be a particularly helpful clue favoring the diagnosis of ventricular tachycardia. Hemodynamic stability, young age, 1:1 AV association, and the absence of structural heart disease do not exclude a diagnosis of ventricular tachycardia. Most wide QRS tachycardias in adults are ventricular, and when all else fails, one will be right more often than not in favoring this as the diagnosis over supraventricular tachycardia with aberrancy. The R to S interval is measured in the precordial (V) leads from the onset of the R wave to the deepest part of the S wave. A value > 100 ms. in any V lead strongly favors ventricular tachycardia. Example is from Case 1 (upper tracing is V1). PMID:8067039

  19. Ischemia detection from morphological QRS angle changes.

    PubMed

    Romero, Daniel; Martínez, Juan Pablo; Laguna, Pablo; Pueyo, Esther

    2016-07-01

    In this paper, an ischemia detector is presented based on the analysis of QRS-derived angles. The detector has been developed by modeling ischemic effects on the QRS angles as a gradual change with a certain transition time and assuming a Laplacian additive modeling error contaminating the angle series. Both standard and non-standard leads were used for analysis. Non-standard leads were obtained by applying the PCA technique over specific lead subsets to represent different potential locations of the ischemic zone. The performance of the proposed detector was tested over a population of 79 patients undergoing percutaneous coronary intervention in one of the major coronary arteries (LAD (n  =  25), RCA (n  =  16) and LCX (n  =  38)). The best detection performance, obtained for standard ECG leads, was achieved in the LAD group with values of sensitivity and specificity of [Formula: see text], [Formula: see text], followed by the RCA group with [Formula: see text], Sp  =  94.4 and the LCX group with [Formula: see text], [Formula: see text], notably outperforming detection based on the ST series in all cases, with the same detector structure. The timing of the detected ischemic events ranged from 30 s up to 150 s (mean  =  66.8 s) following the start of occlusion. We conclude that changes in the QRS angles can be used to detect acute myocardial ischemia. PMID:27243441

  20. Duration of Purkinje cell complex spikes increases with their firing frequency

    PubMed Central

    Warnaar, Pascal; Couto, Joao; Negrello, Mario; Junker, Marc; Smilgin, Aleksandra; Ignashchenkova, Alla; Giugliano, Michele; Thier, Peter; De Schutter, Erik

    2015-01-01

    Climbing fiber (CF) triggered complex spikes (CS) are massive depolarization bursts in the cerebellar Purkinje cell (PC), showing several high frequency spikelet components (±600 Hz). Since its early observations, the CS is known to vary in shape. In this study we describe CS waveforms, extracellularly recorded in awake primates (Macaca mulatta) performing saccades. Every PC analyzed showed a range of CS shapes with profoundly different duration and number of spikelets. The initial part of the CS was rather constant but the later part differed greatly, with a pronounced jitter of the last spikelets causing a large variation in total CS duration. Waveforms did not effect the following pause duration in the simple spike (SS) train, nor were SS firing rates predictive of the waveform shapes or vice versa. The waveforms did not differ between experimental conditions nor was there a preferred sequential order of CS shapes throughout the recordings. Instead, part of their variability, the timing jitter of the CS’s last spikelets, strongly correlated with interval length to the preceding CS: shorter CS intervals resulted in later appearance of the last spikelets in the CS burst, and vice versa. A similar phenomenon was observed in rat PCs recorded in vitro upon repeated extracellular stimulation of CFs at different frequencies in slice experiments. All together these results strongly suggest that the variability in the timing of the last spikelet is due to CS frequency dependent changes in PC excitability. PMID:25918500

  1. Prenatal diagnosis of QT prolongation by fetal magnetocardiogram--use of QRS and T-wave current-arrow maps.

    PubMed

    Kandori, A; Miyashita, T; Tsukada, K; Hosono, T; Miyashita, S; Chiba, Y; Horigome, H; Shigemitsu, S; Asaka, M

    2001-05-01

    To determine the T wave of a fetal magnetocardiogram (FMCG), we have evaluated the T/QRS ratio and obtained current-arrow maps that indicate weak currents. We measured FMCG signals for 52 normal fetuses and two abnormal fetuses with prolonged QT waves by using three superconducting quantum interference device (SQUID) systems: a nine-channel system, a 12-channel vector system and a 64-channel system. The T/QRS ratio was calculated for all the normal fetuses from the maximum magnitudes of the QRS complex and the T wave. Current-arrow maps of the QRS complex (R wave) and T wave were obtained by using the 64-channel system, and the phase differences of the total-current vectors were calculated by using the current-arrow maps. The results showed that the T/QRS ratio had a wide variability of 0.35 for the normal fetuses. However, the magnitude of the prolonged T wave was as weak as the detection limit of the SQUID magnetometer. Although the T/QRS ratios for the fetuses with QT prolongation were within the normal range (< 0.35), the weak magnitude of the prolonged T wave could be evaluated. On the other hand, by comparing the current-arrow maps of the R and T waves for the normal fetuses, we found that the maximum-current arrows were indicated as either in the same direction or in opposite directions. These patterns could be identified clearly by the phase differences. Very weak prolonged T waves for the two abnormal fetuses could be determined by using these current-arrow maps and phase differences. Consequently, although the T/QRS ratios of FMCG signals have a wide distribution, we have concluded that the current-arrow map and phase difference can be used to determine the T wave of an FMCG signal. PMID:11411247

  2. Conditional statistical properties of the complex systems having long-duration memory

    NASA Astrophysics Data System (ADS)

    Huang, Zhifu; Ou, Congjie; Lin, Bihong; Su, Guozhen; Chen, Jincan

    2014-09-01

    A new concept of the available force is proposed to investigate the performance of the complex systems having long-duration memory. Since the covariance of average velocity in double time interval and available force equals zero, it is possible to calculate the conditional probability distribution function (CPDF) within the systems. It is found that the asymmetric CPDF of the velocity between two adjacent time intervals can be derived from the symmetrical CPDF between the available force and the double time interval velocity. Two typical currency exchange databases, i.e., EUR/USD and GBP/USD, which collect the minutely opening exchange prices from 1 January 1999 to 31 December 2011, are adopted as examples. It is found that the analytical CPDF needs only six parameters for an arbitrary system. By calculating the CPDF in the currency exchange databases, it is shown that the results are well fitted by our analytical expression. The analytical CPDF can also be used to calculate the conditional expectation and the conditional variance of velocity. Interestingly, the two databases show that the conditional expectation of the velocity between two adjacent time intervals is not monotonic, while the conditional variance tends to monotonic. All of these results are well described by our theory. It is worthwhile to note that the analytical CPDF is a general expression. It is valid not only for current exchange systems but also for any complex systems having long-duration memory.

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

    PubMed Central

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

    2014-01-01

    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

  4. Narrow QRS systolic heart failure: is there a target for cardiac resynchronization?

    PubMed

    Jackson, Tom; Claridge, Simon; Behar, Jonathan; Sammut, Eva; Webb, Jessica; Carr-White, Gerald; Razavi, Reza; Rinaldi, Christopher Aldo

    2015-01-01

    Cardiac resynchronization therapy has revolutionized the management of systolic heart failure in patients with prolonged QRS during the past 20 years. Initially, the use of this treatment in patients with shorter QRS durations showed promising results, which have since been opposed by larger randomized controlled trials. Despite this, some questions remain, such as, whether correction of mechanical dyssynchrony is the therapeutic target by which biventricular pacing may confer benefit in this group, or are there other mechanisms that need consideration? In addition, novel techniques of cardiac resynchronization therapy delivery such as endocardial and multisite pacing may reduce potential detrimental effects of biventricular pacing, thereby improving the benefit/harm balance of this therapy in some patients.

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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)…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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;…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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)…

  18. Kentucky STARS for KIDS NOW: QRS Profile. The Child Care Quality Rating System (QRS) Assessment

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    This paper presents a profile of Kentucky's STARS for KIDS NOW 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…

  19. North Carolina Star Rated License System: QRS Profile. The Child Care Quality Rating System (QRS) Assessment

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    This paper presents a profile of North Carolina's Star Rated License 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)…

  20. Delaware Stars for Early Success. QRS Profile. The Child Care Quality Rating System (QRS) Assessment

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    This paper presents a profile of Delaware's Stars for Early Success 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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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;…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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…

  4. An Improved QRS Wave Group Detection Algorithm and Matlab Implementation

    NASA Astrophysics Data System (ADS)

    Zhang, Hongjun

    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.

  5. Defining Long-Duration Traverses of Lunar Volcanic Complexes with LROC NAC Images

    NASA Technical Reports Server (NTRS)

    Stopar, J. D.; Lawrence, S. J.; Joliff, B. L.; Speyerer, E. J.; Robinson, M. S.

    2016-01-01

    A long-duration lunar rover [e.g., 1] would be ideal for investigating large volcanic complexes like the Marius Hills (MH) (approximately 300 x 330 km), where widely spaced sampling points are needed to explore the full geologic and compositional variability of the region. Over these distances, a rover would encounter varied surface morphologies (ranging from impact craters to rugged lava shields), each of which need to be considered during the rover design phase. Previous rovers including Apollo, Lunokhod, and most recently Yutu, successfully employed pre-mission orbital data for planning (at scales significantly coarser than that of the surface assets). LROC was specifically designed to provide mission-planning observations at scales useful for accurate rover traverse planning (crewed and robotic) [2]. After-the-fact analyses of the planning data can help improve predictions of future rover performance [e.g., 3-5].

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

    PubMed

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

    2014-10-28

    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

  7. Real-Time 12-Lead High-Frequency QRS Electrocardiography for Enhanced Detection of Myocardial Ischemia and Coronary Artery Disease

    NASA Technical Reports Server (NTRS)

    Schlegel, Todd T.; Kulecz, Walter B.; DePalma, Jude L.; Feiveson, Alan H.; Wilson, John S.; Rahman, M. Atiar; Bungo, Michael W.

    2004-01-01

    Several studies have shown that diminution of the high-frequency (HF; 150-250 Hz) components present within the central portion of the QRS complex of an electrocardiogram (ECG) is a more sensitive indicator for the presence of myocardial ischemia than are changes in the ST segments of the conventional low-frequency ECG. However, until now, no device has been capable of displaying, in real time on a beat-to-beat basis, changes in these HF QRS ECG components in a continuously monitored patient. Although several software programs have been designed to acquire the HF components over the entire QRS interval, such programs have involved laborious off-line calculations and postprocessing, limiting their clinical utility. We describe a personal computer-based ECG software program developed recently at the National Aeronautics and Space Administration (NASA) that acquires, analyzes, and displays HF QRS components in each of the 12 conventional ECG leads in real time. The system also updates these signals and their related derived parameters in real time on a beat-to-beat basis for any chosen monitoring period and simultaneously displays the diagnostic information from the conventional (low-frequency) 12-lead ECG. The real-time NASA HF QRS ECG software is being evaluated currently in multiple clinical settings in North America. We describe its potential usefulness in the diagnosis of myocardial ischemia and coronary artery disease.

  8. Real-time, high frequency QRS electrocardiograph with reduced amplitude zone detection

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

    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.

  9. A joint QRS detection and data compression scheme for wearable sensors.

    PubMed

    Deepu, C J; Lian, Y

    2015-01-01

    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.

  10. A joint QRS detection and data compression scheme for wearable sensors.

    PubMed

    Deepu, C J; Lian, Y

    2015-01-01

    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

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

    PubMed

    Lukoševičius, Mantas; Marozas, Vaidotas

    2014-08-01

    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.

  12. Complex structure of electrophysiological gradients emerging during long-duration ventricular fibrillation in the canine heart.

    PubMed

    Venable, Paul W; Taylor, Tyson G; Shibayama, Junko; Warren, Mark; Zaitsev, Alexey V

    2010-11-01

    Long-duration ventricular fibrillation (LDVF) in the globally ischemic heart is a common setting of cardiac arrest. Electrical heterogeneities during LDVF may affect outcomes of defibrillation and resuscitation. Previous studies in large mammalian hearts have investigated the role of Purkinje fibers and electrophysiological gradients between the endocardium (Endo) and epicardium (Epi). Much less is known about gradients between the right ventricle (RV) and left ventricle (LV) and within each chamber during LDVF. We studied the transmural distribution of the VF activation rate (VFR) in the RV and LV and at the junction of RV, LV, and septum (Sep) during LDVF using plunge needle electrodes in opened-chest dogs. We also used optical mapping to analyze the Epi distribution of VFR, action potential duration (APD), and diastolic interval (DI) during LDVF in the RV and LV of isolated hearts. Transmural VFR gradients developed in both the RV and LV, with a faster VFR in Endo. Concurrently, large VFR gradients developed in Epi, with the fastest VFR in the RV-Sep junction, intermediate in the RV, and slowest in the LV. Optical mapping revealed a progressively increasing VFR dispersion within both the LV and RV, with a mosaic presence of fully inexcitable areas after 4-8 min of LDVF. The transmural, interchamber, and intrachamber VFR heterogeneities were of similar magnitude. In both chambers, the inverse of VFR was highly correlated with DI, but not APD, at all time points of LDVF. We conclude that the complex VFR gradients during LDVF in the canine heart cannot be explained solely by the distribution of Purkinje fibers and are related to regional differences in the electrical depression secondary to LDVF.

  13. [Wide QRS tachycardia preceded by pacemaker spikes].

    PubMed

    Romero, M; Aranda, A; Gómez, F J; Jurado, A

    2014-04-01

    The differential diagnosis and therapeutic management of wide QRS tachycardia preceded by pacemaker spike is presented. The pacemaker-mediated tachycardia, tachycardia fibrillo-flutter in patients with pacemakers, and runaway pacemakers, have a similar surface electrocardiogram, but respond to different therapeutic measures. The tachycardia response to the application of a magnet over the pacemaker could help in the differential diagnosis, and in some cases will be therapeutic, as in the case of a tachycardia-mediated pacemaker. Although these conditions are diagnosed and treated in hospitals with catheterization laboratories using the application programmer over the pacemaker, patients presenting in primary care clinic and emergency forced us to make a diagnosis and treat the haemodynamically unstable patient prior to referral. PMID:23768570

  14. Fetal QRS extraction from abdominal recordings via model-based signal processing and intelligent signal merging.

    PubMed

    Haghpanahi, Masoumeh; Borkholder, David A

    2014-08-01

    Noninvasive fetal ECG (fECG) monitoring has potential applications in diagnosing congenital heart diseases in a timely manner and assisting clinicians to make more appropriate decisions during labor. However, despite advances in signal processing and machine learning techniques, the analysis of fECG signals has still remained in its preliminary stages. In this work, we describe an algorithm to automatically locate QRS complexes in noninvasive fECG signals obtained from a set of four electrodes placed on the mother's abdomen. The algorithm is based on an iterative decomposition of the maternal and fetal subspaces and filtering of the maternal ECG (mECG) components from the fECG recordings. Once the maternal components are removed, a novel merging technique is applied to merge the signals and detect the fetal QRS (fQRS) complexes. The algorithm was trained and tested on the fECG datasets provided by the PhysioNet/CinC challenge 2013. The final results indicate that the algorithm is able to detect fetal peaks for a variety of signals with different morphologies and strength levels encountered in clinical practice.

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

    PubMed

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

    2013-05-01

    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.

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

    PubMed Central

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

    2013-01-01

    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

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

    NASA Technical Reports Server (NTRS)

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

    2006-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    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.

  19. QRS slopes for assessment of myocardial damage in chronic chagasic patients

    NASA Astrophysics Data System (ADS)

    Pueyo, E.; Laciar, E.; Anzuola, E.; Laguna, P.; Jané, R.

    2007-11-01

    In this study the slopes of the QRS complex are evaluated for determination of the degree of myocardial damage in chronic chagasic patients. Previous studies have demonstrated the ability of the slope indices to reflect alterations in the conduction velocity of the cardiac impulse. Results obtained in the present study show that chronic chagasic patients have significantly flatter QRS slopes as compared to healthy subjects. Not only that but the extent of slope lessening turns out to be proportional to the degree of myocardial damage caused by the disease. Additionally, when incorporating the slope indices into a classification analysis together with other indices indicative of the presence of ventricular late potentials obtained from high resolution electrocardiography, results show that the percentages of correct classification increase up to 62.5%, which means eight points above the percentages obtained prior to incorporation of the slope indices. It can be concluded that QRS slopes have great potential for assessing the degree of severity associated with Chagas' disease.

  20. Progress in resolving the duration of magmatism in the Paleoproterozoic Bushveld Complex

    NASA Astrophysics Data System (ADS)

    Scoates, J. S.; Wall, C. J.; Friedman, R. M.; VanTongeren, J. A.; Mathez, E. A.

    2011-12-01

    Determining precise crystallization ages and assessing the duration of magmatism associated with the Paleoproterozoic Bushveld Complex, the world's largest layered intrusion located in the northern Kaapvaal craton of South Africa, is critical for establishing the genetic relations among its different rock units (Rustenburg Layered Suite, overlying Rooiberg Group felsic volcanic rocks, intrusive Rashoop Granophyres). We report chemical abrasion ID-TIMS U-Pb zircon results (weighted 207Pb/206Pb ages) for samples spanning the uppermost ~3/4 of the igneous stratigraphy of the layered mafic rocks and the roof. The temporal relationship between the Upper Zone and the roof from the Eastern Limb is constrained by the age of a diorite ~52 m below the roof (2056.52 ± 0.81 Ma; n = 6 single grains) and a granodiorite mixed with hornfels (40:60) and interpreted as partially melted roof material (2054.83 ± 0.86 Ma; n = 7). The slightly younger age of the granodiorite may indicate that the overlying melt sheet was kept molten due to continued influx of the latent heat of crystallization from the underlying 8 km-thick stack of cooling cumulates. The PGE-rich Merensky Reef and the UG2 chromitite occur in the Upper Critical Zone above the ultramafic rocks that comprise the base of the complex. Two samples from the Merensky Reef, separated by ~300 km, have overlapping ages: a sample from Farm Driekop in the Eastern Limb yields an age of 2055.30 ± 0.61 Ma (n = 10) and a sample from the Rustenburg mining section in the Western Limb an age of 2056.13 ± 0.70 Ma (n = 8; age revised from [1]). These ages are indistinguishable from the Upper Zone diorite indicating rapid construction of the upper 2/3 of the Bushveld Complex at ca. 2056 Ma. Preliminary results for zircon from a feldspathic orthopyroxenite immediately beneath the UG2 chromitite (Middelpunt mine, Eastern Limb), ~380 m below the Merensky Reef, reveal unusual U-Pb systematics with low U concentrations (2-27 ppm

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

    PubMed

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

    2011-01-01

    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 ( ℑ(US)) and downward ( ℑ(DS) ) slopes of the R wave as well as the upward ( ℑ(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 ℑ(US), ℑ(DS), and ℑ(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 ℑ(US), ℑ(DS), and ℑ(TS) present high stability in the resting state, thus providing a stable reference for ischemia characterization. Maximum relative factors of change ( ℜ(ℑ)) 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 ℑ(US) and ℑ(DS), respectively. For standard leads, the relative factors of change were 6.01 and 9.31. The ℑ(TS) index presented a similar behavior to that of ℑ(DS). The timing for the occurrence of significant changes in ℑ(US) and ℑ(DS) varied with lead, ranging from 30 s to 2 min after initiation of coronary occlusion. In the present ischemia model, relative ℑ(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.

  2. Low Power Adder Based Digital Filter for QRS Detector

    PubMed Central

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

    2014-01-01

    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

  3. Low power adder based digital filter for QRS detector.

    PubMed

    Murali, L; Chitra, D; Manigandan, T

    2014-01-01

    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.

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

    PubMed Central

    Krivokapi, Jelena

    2007-01-01

    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

  5. The complex duration perception of emotional faces: effects of face direction

    PubMed Central

    Kliegl, Katrin M.; Limbrecht-Ecklundt, Kerstin; Dürr, Lea; Traue, Harald C.; Huckauf, Anke

    2015-01-01

    The perceived duration of emotional face stimuli strongly depends on the expressed emotion. But, emotional faces also differ regarding a number of other features like gaze, face direction, or sex. Usually, these features have been controlled by only using pictures of female models with straight gaze and face direction. Doi and Shinohara (2009) reported that an overestimation of angry faces could only be found when the model’s gaze was oriented toward the observer. We aimed at replicating this effect for face direction. Moreover, we explored the effect of face direction on the duration perception sad faces. Controlling for the sex of the face model and the participant, female and male participants rated the duration of neutral, angry, and sad face stimuli of both sexes photographed from different perspectives in a bisection task. In line with current findings, we report a significant overestimation of angry compared to neutral face stimuli that was modulated by face direction. Moreover, the perceived duration of sad face stimuli did not differ from that of neutral faces and was not influenced by face direction. Furthermore, we found that faces of the opposite sex appeared to last longer than those of the same sex. This outcome is discussed with regards to stimulus parameters like the induced arousal, social relevance, and an evolutionary context. PMID:25852589

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

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

    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.

  7. Sonar sound groups and increased terminal buzz duration reflect task complexity in hunting bats

    PubMed Central

    Hulgard, Katrine; Ratcliffe, John M.

    2016-01-01

    More difficult tasks are generally regarded as such because they demand greater attention. Echolocators provide rare insight into this relationship because biosonar signals can be monitored. Here we show that bats produce longer terminal buzzes and more sonar sound groups during their approach to prey under presumably more difficult conditions. Specifically, we found Daubenton’s bats, Myotis daubentonii, produced longer buzzes when aerial-hawking versus water-trawling prey, but that bats taking revolving air- and water-borne prey produced more sonar sound groups than did the bats when taking stationary prey. Buzz duration and sonar sound groups have been suggested to be independent means by which bats attend to would-be targets and other objects of interest. We suggest that for attacking bats both should be considered as indicators of task difficulty and that the buzz is, essentially, an extended sonar sound group. PMID:26857019

  8. Sonar sound groups and increased terminal buzz duration reflect task complexity in hunting bats.

    PubMed

    Hulgard, Katrine; Ratcliffe, John M

    2016-01-01

    More difficult tasks are generally regarded as such because they demand greater attention. Echolocators provide rare insight into this relationship because biosonar signals can be monitored. Here we show that bats produce longer terminal buzzes and more sonar sound groups during their approach to prey under presumably more difficult conditions. Specifically, we found Daubenton's bats, Myotis daubentonii, produced longer buzzes when aerial-hawking versus water-trawling prey, but that bats taking revolving air- and water-borne prey produced more sonar sound groups than did the bats when taking stationary prey. Buzz duration and sonar sound groups have been suggested to be independent means by which bats attend to would-be targets and other objects of interest. We suggest that for attacking bats both should be considered as indicators of task difficulty and that the buzz is, essentially, an extended sonar sound group. PMID:26857019

  9. Sonar sound groups and increased terminal buzz duration reflect task complexity in hunting bats.

    PubMed

    Hulgard, Katrine; Ratcliffe, John M

    2016-01-01

    More difficult tasks are generally regarded as such because they demand greater attention. Echolocators provide rare insight into this relationship because biosonar signals can be monitored. Here we show that bats produce longer terminal buzzes and more sonar sound groups during their approach to prey under presumably more difficult conditions. Specifically, we found Daubenton's bats, Myotis daubentonii, produced longer buzzes when aerial-hawking versus water-trawling prey, but that bats taking revolving air- and water-borne prey produced more sonar sound groups than did the bats when taking stationary prey. Buzz duration and sonar sound groups have been suggested to be independent means by which bats attend to would-be targets and other objects of interest. We suggest that for attacking bats both should be considered as indicators of task difficulty and that the buzz is, essentially, an extended sonar sound group.

  10. QRS fragmentation: its role in sherlocking the arrhythmogenic heart

    PubMed Central

    Virk, Hafeez Ul Hassan; Farooq, Salman; Ghani, Ali Raza; Arora, Shilpkakumar

    2016-01-01

    The electrocardiogram (ECG) is a commonly available basic diagnostic modality in in-patient, out-patient, and emergency departments. In patients with coronary artery disease (CAD), the presence of a fragmented QRS (f-QRS), which is an extra R wave (R′), notching of the single R wave, notching of the S wave in at least two contiguous leads on the 12-lead ECG, is associated with a myocardial scar from previous myocardial injury. Furthermore, the presence of f-QRS has been shown to be associated with adverse outcomes in CAD and non-CAD patients. In the present paper, we will solely focus on the usefulness and utilization of f-QRS in predicting ventricular tachyarrhythmia in many heart diseases, that is, ischemic cardiomyopathy, non-ischemic cardiomyopathy, hypertrophic obstructive cardiomyopathy, Brugada syndrome, and arrhythmogenic right ventricular cardiomyopathy. In the majority of such cases, ventricular tachyarrhythmia results in sudden cardiac death. Diagnosing them beforehand can lead to prevention and/or early treatment of these arrhythmias to prevent potential morbidity and mortality. PMID:27406448

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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;…

  12. Los Angeles County Steps to Excellence Project: QRS Profile. The Child Care Quality Rating System (QRS) Assessment

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    This paper presents a profile of Los Angeles County's Steps to Excellence Project 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;…

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

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    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)…

  14. New Mexico Look for the STARS--AIM HIGH: QRS Profile. The Child Care Quality Rating System (QRS) Assessment

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    This paper presents a profile of New Mexico's Look for the STARS--AIM HIGH 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)…

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

    PubMed

    Zhang, Pu; Ma, Heather T; Zhang, Qinyu

    2014-01-01

    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

  16. Reducing false arrhythmia alarms in the ICU using multimodal signals and robust QRS detection.

    PubMed

    Sadr, Nadi; Huvanandana, Jacqueline; Nguyen, Doan Trang; Kalra, Chandan; McEwan, Alistair; de Chazal, Philip

    2016-08-01

    This study developed algorithms to decrease the arrhythmia false alarms in the ICU by processing multimodal signals of photoplethysmography (PPG), arterial blood pressure (ABP), and two ECG signals. The goal was to detect the five critical arrhythmias comprising asystole (ASY), extreme bradycardia (EBR), extreme tachycardia (ETC), ventricular tachycardia (VTA), and ventricular flutter or fibrillation (VFB). The different characteristics of the arrhythmias suggested the application of individual signal processing for each alarm and the combination of the algorithms to enhance false alarm detection. Thus, different features and signal processing techniques were used for each arrhythmia type. The ECG signals were first processed to reduce the signal interference. Then, a Hilbert-transform based QRS detector algorithm was utilized to identify the QRS complexes, which were then processed to determine the instantaneous heart rate. The pulsatile signals (PPG and ABP) were processed to discover the pulse onset of beats which were then employed to measure the heart rate. The signal quality index (SQI) of the signals was implemented to verify the integrity of the heart rate information. The overall score obtained by our algorithms in the 2015 Computing in Cardiology Challenge was a score of 74.03% for retrospective and 69.92% for real-time analysis. PMID:27455121

  17. High frequency QRS ECG predicts ischemic defects during myocardial perfusion imaging

    NASA Technical Reports Server (NTRS)

    Rahman, Atiar

    2006-01-01

    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.

  18. High frequency QRS ECG predicts ischemic defects during myocardial perfusion imaging

    NASA Technical Reports Server (NTRS)

    2004-01-01

    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.

  19. Real-Time, High-Frequency QRS Electrocardiograph

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

    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

  20. Compendium of Quality Rating Systems and Evaluations: The Child Care Quality Rating System (QRS) Assessment

    ERIC Educational Resources Information Center

    Tout, Kathryn; Starr, Rebecca; Soli, Margaret; Moodie, Shannon; Kirby, Gretchen; Boller, Kimberly

    2010-01-01

    Quality Rating Systems (QRS) are currently operating, under development, or being piloted in over 25 states or local areas. As the QRS model becomes integrated into the landscape of child care and education service delivery, policy, and the decisions parents make about child care across the United States, there is an increasing need for…

  1. Circulating serum markers and QRS scar score in Chagas cardiomyopathy.

    PubMed

    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

    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-β1 (TGFβ1), and TGFβ2 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.

  2. Circulating Serum Markers and QRS Scar Score in Chagas Cardiomyopathy

    PubMed Central

    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

    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-β1 (TGFβ1), and TGFβ2 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

  3. Risk of mortality in individuals with low QRS voltage and free of cardiovascular disease.

    PubMed

    Usoro, Andrew O; Bradford, Natalie; Shah, Amit J; Soliman, Elsayed Z

    2014-05-01

    The prognostic significance of low QRS voltage (LQRSV) in the electrocardiogram (ECG) of individuals free of cardiovascular disease (CVD) is unclear. We evaluated the association between LQRSV and all-cause mortality in 6,440 participants (53% women, mean age 60 years) from the Third National Health and Nutrition Examination Survey, a representative sample of the US population. Participants with history of CVD or major ECG abnormalities were excluded. LQRSV was automatically defined from standard 12-lead ECG as QRS complex amplitudes of <0.5 mV in all frontal leads and/or <1.0 mV in all precordial leads. Mortality data through 2006 were obtained from National Death Index records. LQRSV was detected in 1.4% (n = 89) of the participants. During a median follow-up of 13.8 years, 2,000 deaths occurred. The mortality rate in individuals with LQRSV was almost twice that in those without LQRSV (51.1 vs 23.5 events per 1,000 person-years, p <0.01). In a demographic-adjusted model, LQRSV was associated with 63% increased risk of mortality (hazard ratio 1.63, 95% confidence interval [1.21, 2.18]). The magnitude of this risk did not appreciably change after additional adjustment for body mass index, smoking status, systolic blood pressure, blood pressure medication use, dyslipidemia, diabetes, cancer, pulmonary disease, and ECG abnormalities (hazard ratio 1.61, 95% confidence interval [1.20, 2.16]) and was consistent across age, race, and sex subcategories. In conclusion, LQRSV is associated with an increased risk of mortality in individuals free of apparent CVD. More research is warranted to determine the mechanisms by which LQRSV is associated with increased risk of mortality in apparently healthy individuals. PMID:24630386

  4. Development of a Multi-Channel, High Frequency QRS Electrocardiograph

    NASA Technical Reports Server (NTRS)

    DePalma, Jude L.

    2003-01-01

    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

  5. Prognostic Significance of Frontal QRS-T Angle in Patients with Idiopathic Dilated Cardiomyopathy

    PubMed Central

    Li, Sheng-Na; Zhang, Xin-Lin; Cai, Guo-Long; Lin, Ruo-Wei; Jiang, He; Chen, Jian-Zhou; Xu, Biao; Huang, Wei

    2016-01-01

    Background: Current risk stratification of idiopathic dilated cardiomyopathy (IDC) lacks sufficient sensitivity and specificity. The objective of this study was to investigate the predictive role of frontal QRS-T angles in IDC. Methods: A prospective study with 509 IDC patients was performed from February 2008 to December 2013 in the Affiliated Drum Tower Hospital, Nanjing University School of Medicine. Baseline values and changes in QRS-T angles were recorded. Follow-up was conducted every 6 months. Analyses by Cox Proportional Hazards model were performed to evaluate the association between QRS-T angle and outcomes. The primary outcome of interest was all-cause mortality. Results: During a median follow-up of 34 months, 90 of 316 patients with QRS-T angles >90° died compared to 31 of 193 patients with QRS-T angles ≤90° (hazard ratio [HR] =2.4, P < 0.001). Cardiac death was more prevalent in patients with a wide QRS-T angle (HR = 2.4, P < 0.001), similar to heart failure rehospitalization (HR = 2.5, P < 0.001). After adjustment for potential prognostic factors, the QRS-T angle was independently associated with all-cause mortality (HR = 2.5, P < 0.05), cardiac mortality (HR = 1.9, P < 0. 05), and heart failure rehospitalization (HR = 2.3, P < 0.01). Optimized therapy significantly narrowed the frontal QRS-T angle (100.9 ± 53.4° vs. 107.2 ± 54.4°, P < 0.001). The frontal QRS-T angle correlated well with established risk factors, such as left ventricular ejection fraction, brain natriuretic peptide, and New York Heart Association functional class. Conclusions: The frontal QRS-T angle is a powerful predictor of all-cause mortality, cardiac mortality, and worsening heart failure in IDC patients, independent of well-established prognostic factors. Optimized therapy significantly narrows the QRS-T angle, which might be an indicator of medication compliance, but this requires further investigation. PMID:27503013

  6. Partial suppression of the respiratory defect of qrs1/her2 glutamyl-tRNA amidotransferase mutants by overexpression of the mitochondrial pentatricopeptide Msc6p.

    PubMed

    Moda, Bruno S; Ferreira-Júnior, José Ribamar; Barros, Mario H

    2016-08-01

    Recently, a large body of evidences indicates the existence in the mitochondrial matrix of foci that contain different proteins involved in mitochondrial RNA metabolism. Some of these proteins have a pentatricopeptide repeat motif that constitutes their RNA-binding structures. Here we report that MSC6, a mitochondrial pentatricopeptide protein of unknown function, is a multi copy suppressor of mutations in QRS1/HER2 a component of the trimeric complex that catalyzes the transamidation of glutamyl-tRNAQ to glutaminyl-tRNAQ. This is an essential step in mitochondrial translation because of the lack of a specific mitochondrial aminoacyl glutaminyl-tRNA synthetase. MSC6 over-expression did not abolish translation of an aberrant variant form of Cox2p detected in QRS1/HER2 mutants, arguing against a suppression mechanism that bypasses Qrs1p function. A slight decrement of the mitochondrial translation capacity as well as diminished growth on respiratory carbon sources media for respiratory activity was observed in the msc6 null mutant. Additionally, the msc6 null mutant did not display any impairment in RNA transcription, processing or turnover. We concluded that Msc6p is a mitochondrial matrix protein and further studies are required to indicate the specific function of Msc6p in mitochondrial translation.

  7. A 0.83- μW QRS detection processor using quadratic spline wavelet transform for wireless ECG acquisition in 0.35- μm CMOS.

    PubMed

    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

    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-μm CMOS the 300-Hz processor draws only 0.83 μW, 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.

  8. District of Columbia Going for the Gold Tiered Rate Reimbursement System. QRS Profile. The Child Care Quality Rating System (QRS) Assessment

    ERIC Educational Resources Information Center

    Child Trends, 2010

    2010-01-01

    This paper presents a profile of District of Columbia's Going for the Gold Tiered Rate Reimbursement Systemp repared 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…

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

    PubMed Central

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

    2013-01-01

    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-α) has been linked to cardiomyopathy in experimental models and in patients with Chagas disease, other reports suggest that TNF-α may exert anti-parasitic actions during the acute phase of infection. Objectives This study aimed to determine the effects of a soluble TNF-α 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-α 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

  10. Frequency, origin, and outcome of ventricular premature complexes in patients with or without heart diseases.

    PubMed

    Lee, Ying-Hsiang; Zhong, Li; Roger, Veronique L; Asirvatham, Samuel J; Shen, Win-Kuang; Slusser, Joshua P; Hodge, David O; Cha, Yong-Mei

    2014-11-01

    The objective of the present study was to investigate the relation of ventricular premature complex (VPC) burden, origin, and electrocardiographic characteristics with left ventricular function and survival. Of 1,589 study patients, 388 (25%), 610 (38%), and 591 (37%) had low (<1,000/24 hours), moderate (1,000 to 10,000/24 hours), and high (>10,000/24 hours) VPC burden, respectively. Twenty-three percent of study patients had a left ventricular (LV) ejection fraction <50% (8% in low-, 20% in moderate-, and 36% in high-VPC-burden groups, p <0.001). High VPC burden was associated with lower LV ejection fraction in the presence (r = -0.17, p <0.001) and absence (r = -0.20, p <0.001) of heart diseases. The Kaplan-Meier survival estimates showed a significant difference among the 3 VPC burden groups (p = 0.046). The survival rates were significantly lower for patients with a VPC coupling interval of ≥480 ms than those with a VPC coupling interval of <480 ms (p = 0.002) and lower for those with a VPC QRS duration of ≥150 ms than those with a VPC QRS duration of <150 ms (p <0.001). In conclusion, high VPC burden is detrimental to LV systolic function. Broader VPC QRS duration and longer VPC coupling interval adversely impact on long-term survival.

  11. Development of an automated updated Selvester QRS scoring system using SWT-based QRS fractionation detection and classification.

    PubMed

    Bono, Valentina; Mazomenos, Evangelos B; Chen, Taihai; Rosengarten, James A; Acharyya, Amit; Maharatna, Koushik; Morgan, John M; Curzen, Nick

    2014-01-01

    The Selvester score is an effective means for estimating the extent of myocardial scar in a patient from low-cost ECG recordings. Automation of such a system is deemed to help implementing low-cost high-volume screening mechanisms of scar in the primary care. This paper describes, for the first time to the best of our knowledge, an automated implementation of the updated Selvester scoring system for that purpose, where fractionated QRS morphologies and patterns are identified and classified using a novel stationary wavelet transform (SWT)-based fractionation detection algorithm. This stage informs the two principal steps of the updated Selvester scoring scheme--the confounder classification and the point awarding rules. The complete system is validated on 51 ECG records of patients detected with ischemic heart disease. Validation has been carried out using manually detected confounder classes and computation of the actual score by expert cardiologists as the ground truth. Our results show that as a stand-alone system it is able to classify different confounders with 94.1% accuracy whereas it exhibits 94% accuracy in computing the actual score. When coupled with our previously proposed automated ECG delineation algorithm, that provides the input ECG parameters, the overall system shows 90% accuracy in confounder classification and 92% accuracy in computing the actual score and thereby showing comparable performance to the stand-alone system proposed here, with the added advantage of complete automated analysis without any human intervention.

  12. Interglacial Durations

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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 δ18O stack (LR04) as a proxy for sea level/ice volume, ice core (Vostok, EDC) atmospheric CO2 and additional records. Although

  13. Frictional Heat Generation and Slip Duration Estimated From Micro-fault in an Exhumed Accretionary Complex and Their Relations to the Scaling Law for Slow Earthquakes

    NASA Astrophysics Data System (ADS)

    Hashimoto, Y.; Morita, K.; Okubo, M.; Hamada, Y.; Lin, W.; Hirose, T.; Kitamura, M.

    2015-12-01

    Fault motion has been estimated by diffusion pattern of frictional heating recorded in geology (e.g., Fulton et al., 2012). The same record in deeper subduction plate interface can be observed from micro-faults in an exhumed accretionary complex. In this study, we focused on a micro-fault within the Cretaceous Shimanto Belt, SW Japan to estimate fault motion from the frictional heating diffusion pattern. A carbonaceous material concentrated layer (CMCL) with ~2m of thickness is observed in study area. Some micro-faults cut the CMCL. Thickness of a fault is about 3.7mm. Injection veins and dilatant fractures were observed in thin sections, suggesting that the high fluid pressure was existed. Samples with 10cm long were collected to measure distribution of vitrinite reflectance (Ro) as a function of distance from the center of micro-fault. Ro of host rock was ~1.0%. Diffusion pattern was detected decreasing in Ro from ~1.2%-~1.1%. Characteristic diffusion distance is ~4-~9cm. We conducted grid search to find the optimal frictional heat generation per unit area (Q, the product of friction coefficient, normal stress and slip velocity) and slip duration (t) to fit the diffusion pattern. Thermal diffusivity (0.98*10-8m2/s) and thermal conductivity (2.0 W/mK) were measured. In the result, 2000-2500J/m2 of Q and 63000-126000s of t were estimated. Moment magnitudes (M0) of slow earthquakes (slow EQs) follow a scaling law with slip duration and its dimension is different from that for normal earthquakes (normal EQ) (Ide et al., 2007). The slip duration estimated in this study (~104-~105s) consistent with 4-5 of M0, never fit to the scaling law for normal EQ. Heat generation can be inverted from 4-5 of M0, corresponding with ~108-~1011J, which is consistent with rupture area of 105-108m2 in this study. The comparisons in heat generation and slip duration between geological measurements and geophysical remote observations give us the estimation of rupture area, M0, and

  14. Robust fetal QRS detection from noninvasive abdominal electrocardiogram based on channel selection and simultaneous multichannel processing.

    PubMed

    Ghaffari, Ali; Mollakazemi, Mohammad Javad; Atyabi, Seyyed Abbas; Niknazar, Mohammad

    2015-12-01

    The purpose of this study is to provide a new method for detecting fetal QRS complexes from non-invasive fetal electrocardiogram (fECG) signal. Despite most of the current fECG processing methods which are based on separation of fECG from maternal ECG (mECG), in this study, fetal heart rate (FHR) can be extracted with high accuracy without separation of fECG from mECG. Furthermore, in this new approach thoracic channels are not necessary. These two aspects have reduced the required computational operations. Consequently, the proposed approach can be efficiently applied to different real-time healthcare and medical devices. In this work, a new method is presented for selecting the best channel which carries strongest fECG. Each channel is scored based on two criteria of noise distribution and good fetal heartbeat visibility. Another important aspect of this study is the simultaneous and combinatorial use of available fECG channels via the priority given by their scores. A combination of geometric features and wavelet-based techniques was adopted to extract FHR. Based on fetal geometric features, fECG signals were divided into three categories, and different strategies were employed to analyze each category. The method was validated using three datasets including Noninvasive fetal ECG database, DaISy and PhysioNet/Computing in Cardiology Challenge 2013. Finally, the obtained results were compared with other studies. The adopted strategies such as multi-resolution analysis, not separating fECG and mECG, intelligent channels scoring and using them simultaneously are the factors that caused the promising performance of the method. PMID:26462679

  15. Complex movement topography and extrinsic space representation in the rat forelimb motor cortex as defined by long-duration intracortical microstimulation.

    PubMed

    Bonazzi, Laura; Viaro, Riccardo; Lodi, Enrico; Canto, Rosario; Bonifazzi, Claudio; Franchi, Gianfranco

    2013-01-30

    Electrical stimulation of the motor cortex in the rat can evoke complex forelimb multi-joint movements, including movement of limb and paw. In this study, these movements have been quantified in terms of 3D displacement and kinematic variables of two markers positioned on the wrist and middle digits (limb and paw movement, respectively). Electrical microstimulation was applied to the motor cortex using a pulse train of 500 ms duration. Movements were measured using a high-resolution 3D optical system. Five classes of limb movements (abduction, adduction, extension, retraction, elevation) and four classes of paw movements (opening, closure, opening/closure sequence, supination) were described according to their kinematics. A consistent topography of these classes of movements was presented across the motor cortex together with a topography of spatial locations to which the paw was directed. In about one-half of cortical sites, a specific pattern of limb-paw movement combination did exist. Four categories of limb-paw movements resembling behavioral repertoire were identified: reach-shaping, reach-grasp sequence, bring-to-body, and hold-like movement. Overall, the forelimb motor region included: (1) a large caudal forelimb area dominated by reach-shaping movement representation; (2) a small rostral area containing reach-grasp sequence and bring-to-body movement representation; and (3) a more lateral portion where hold-like movement was represented. These results support the view that, in rats, the motor cortex controls forelimb movements at a relatively complex level and suggest that the orderly representation of complex movements and their dynamics/kinematics emerge from the principles of forelimb motor cortex organization. PMID:23365246

  16. QRS-ST-T triangulation with repolarization shortening as a precursor of sustained ventricular tachycardia during acute myocardial ischemia.

    PubMed

    Batchvarov, Velislav N; Behr, Elijah R

    2015-04-01

    We present segments from a 24-hour 12-lead digital Holter recording in a 48-year-old man demonstrating transient ST elevations in the inferior leads that triggered sustained ventricular tachycardia/ventricular fibrillation (VT/VF) requiring cardioversion. The onset of VT was preceded by a gradual increase in the ST with marked QRS broadening that lacked distinction between the end of the QRS and the beginning of the ST (QRS-ST-T "triangulation"), and shortening of the QT interval not caused by an increased heart rate. This is a relatively rare documentation of the mechanisms immediately triggering sustained ventricular arrhythmias during acute myocardial ischemia obtained with 12-lead ECG.

  17. Fast QRS Detection with an Optimized Knowledge-Based Method: Evaluation on 11 Standard ECG Databases

    PubMed Central

    Elgendi, Mohamed

    2013-01-01

    The current state-of-the-art in automatic QRS detection methods show high robustness and almost negligible error rates. In return, the methods are usually based on machine-learning approaches that require sufficient computational resources. However, simple-fast methods can also achieve high detection rates. There is a need to develop numerically efficient algorithms to accommodate the new trend towards battery-driven ECG devices and to analyze long-term recorded signals in a time-efficient manner. A typical QRS detection method has been reduced to a basic approach consisting of two moving averages that are calibrated by a knowledge base using only two parameters. In contrast to high-accuracy methods, the proposed method can be easily implemented in a digital filter design. PMID:24066054

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

    PubMed

    Amit, Guy; Granot, Yair; Abboud, Shimon

    2014-01-01

    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.

  19. Electrocardiogram derived respiratory rate from QRS slopes and R-wave angle.

    PubMed

    Lázaro, Jesús; Alcaine, Alejandro; Romero, Daniel; Gil, Eduardo; Laguna, Pablo; Pueyo, Esther; Bailón, Raquel

    2014-10-01

    A method for estimating respiratory rate from electrocardiogram (ECG) signals is presented. It is based on QRS slopes and R-wave angle, which reflect respiration-induced beat morphology variations. The 12 standard leads, 3 leads from vectorcardiogram (VCG), and 2 additional non-standard leads derived from VCG loops were analyzed. The following series were studied as ECG derived respiration (EDR) signals: slope between the peak of Q and R waves, slope between the peak of R and S waves, and the R-wave angle. Information from several EDR signals was combined in order to increase the robustness of estimation. Evaluation is performed over two databases containing ECG and respiratory signals simultaneously recorded during two clinical tests with different characteristics: tilt test, representing abrupt cardiovascular changes, and stress test representing a highly non-stationary and noisy environment. A combination of QRS slopes and R-wave angle series derived from VCG leads obtained a respiratory rate estimation relative error of 0.50 ± 4.11% (measuring 99.84% of the time) for tilt test and 0.52 ± 8.99% (measuring 96.09% of the time) for stress test. These results outperform those obtained by other reported methods, both in tilt and stress testing.

  20. Validation of Standard and New Criteria for the Differential Diagnosis of Narrow QRS Tachycardia in Children and Adolescents

    PubMed Central

    Deutsch, Karol; Stec, Sebastian; Kukla, Piotr; Morka, Aleksandra; Jastrzebski, Marek; Baszko, Artur; Pitak, Maciej; Sledz, Janusz; Fijorek, Kamil; Mazij, Mariusz; Ludwik, Bartosz; Gubaro, Marcin; Szydlowski, Leslaw

    2015-01-01

    Abstract To establish an appropriate treatment strategy and determine if ablation is indicated for patients with narrow QRS complex supraventricular tachycardia (SVT), analysis of a standard 12-lead electrocardiogram (ECG) is required, which can differentiate between the 2 most common mechanisms underlying SVT: atrioventricular nodal reentry tachycardia (AVNRT) and orthodromic atrioventricular reentry tachycardia (OAVRT). Recently, new, highly accurate electrocardiographic criteria for the differential diagnosis of SVT in adults were proposed; however, those criteria have not yet been validated in a pediatric population. All ECGs were recorded during invasive electrophysiology study of pediatric patients (n = 212; age: 13.2 ± 3.5, range: 1–18; girls: 48%). We assessed the diagnostic value of the 2 new and 7 standard criteria for differentiating AVNRT from OAVRT in a pediatric population. Two of the standard criteria were found significantly more often in ECGs from the OAVRT group than from the AVNRT group (retrograde P waves [63% vs 11%, P < 0.001] and ST-segment depression in the II, III, aVF, V1–V6 leads [42% vs 27%; P < 0.05]), whereas 1 standard criterion was found significantly more often in ECGs from the AVNRT group than from the OAVRT group (pseudo r′ wave in V1 lead [39% vs 10%, P < 0.001]). The remaining 6 criteria did not reach statistical significance for differentiating SVT, and the accuracy of prediction did not exceed 70%. Based on these results, a multivariable decision rule to evaluate differential diagnosis of SVT was performed. These results indicate that both the standard and new electrocardiographic criteria for discriminating between AVNRT and OAVRT have lower diagnostic values in children and adolescents than in adults. A decision model based on 5 simple clinical and ECG parameters may predict a final diagnosis with better accuracy. PMID:26705217

  1. 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)

    Schlegel, Todd T.; Cortez, Daniel

    2010-01-01

    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.

  2. Fine grid computer simulation of QRS-T and criteria for the quantitation of regional ischemia.

    PubMed

    Selvester, R H; Solomon, J C; Tolan, G D

    1987-10-01

    A comprehensive fine grid simulation of excitation and recovery (QRS-T), realistic cardiac and torso anatomy, and electrophysiologic properties has been developed that produces a total body surface electrocardiogram (ECG) as output. The simulation leads to the specific hypothesis that additional leads on the upper and lower torso, and on the back, are required to optimize the quantitation and localization of regional ischemia and infarction. Criteria in the STT portion of the ECG for quantitating the severity of the ischemia were developed and presented. The combination of the leads in which the STT changes occur and the severity of the STT change provide a testable set of hypotheses for predicting the severity of ischemia, the probable coronary perfusion bed involved, the severity of the perfusion defect, and the severity of the proximal coronary obstruction. PMID:3694084

  3. A Literature Review of the Use of Sodium Bicarbonate for the Treatment of QRS Widening.

    PubMed

    Bruccoleri, Rebecca E; Burns, Michele M

    2016-03-01

    Sodium bicarbonate is a well-known antidote for tricyclic antidepressant (TCA) poisoning. It has been used for over half a century to treat toxin-induced sodium channel blockade as evidenced by QRS widening on the electrocardiogram (ECG). The purpose of this review is to describe the literature regarding electrophysiological mechanisms and clinical use of this antidote after poisoning by tricyclic antidepressants and other agents. This article will also address the literature supporting an increased serum sodium concentration, alkalemia, or the combination of both as the responsible mechanism(s) for sodium bicarbonate's antidotal properties. While sodium bicarbonate has been used as a treatment for cardiac sodium channel blockade for multiple other agents including citalopram, cocaine, flecainide, diphenhydramine, propoxyphene, and lamotrigine, it has uncertain efficacy with bupropion, propranolol, and taxine-containing plants.

  4. A 300-mV 220-nW event-driven ADC with real-time QRS detection for wearable ECG sensors.

    PubMed

    Zhang, Xiaoyang; Lian, Yong

    2014-12-01

    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 μm 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

  5. 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)

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

    2013-09-01

    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.

  6. Effects of electrocardiograph frequency filters on P-QRS-T amplitudes of the feline electrocardiogram.

    PubMed

    Schrope, D P; Fox, P R; Hahn, A W; Bond, B; Rosenthal, S

    1995-11-01

    OBJECTIVE--To determine whether standard manual frequency filters in the ON and OFF settings affected P-QRS-T voltages, discover whether recorded P-QRS-T voltages vary between commercial electrocardiographs, assess effects of frequency filters on base-line artifact, and evaluate ECG frequency content by high-fidelity recordings subjected to digital filters with variable frequencies. DESIGN--Sequential 10-lead ECG were recorded in 30 cats, using 3 commercial electrocardiographs to assess effects of manual frequency filters on the P-QRS-T wave forms. Three clinically normal cats were evaluated for ECG frequency content. ANIMALS--Thirty cats (13 with hypertrophic cardiomyopathy; 4 with restrictive cardiomyopathy; 3 hyperthyroid; 1 with ventricular septal defect; 1 with aortic stenosis; and 8 with no detectable cardiovascular disease). Three additional clinically normal cats were studied for effects of frequency filters on the ECG frequency content. PROCEDURES--Ten-lead ECG were recorded on each cat by use of 3 commercial electrocardiographs sequentially. For each machine, a recording was made with manual filters ON, immediately followed by a recording with manual filters OFF. High-fidelity lead-II ECG recordings were made with filters set with their rolloff frequency at 0.1 Hz and 3.0 kHz; output voltage (0.2 mV/V) was fed to an analog-to-digital converter, then to attendant software, which sampled the signal at 6 kHz with a 12-bit sampler, and were digitally filtered at various corner frequencies. RESULTS--Voltages recorded by all 3 electrocardiographs were greatest when filters were OFF (most prominent on R- and S-wave voltages). In all recorded leads, R-wave voltage was significantly greater when filters were OFF than ON. Comparison of voltages indicated significant (P < 0.05) differences between R-wave voltages recorded in all leads with manual filters ON, but not with filters OFF. With filters ON, each electrocardiograph produced a smaller percentage of

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

    PubMed Central

    S., Chandrasekharappa; Brid, S.V

    2014-01-01

    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

  8. 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

    2014-01-01

    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

  9. 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

    Kurbel, Sven

    2014-01-01

    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

  10. [Sleep duration and metabolism].

    PubMed

    Viot-Blanc, V

    2015-12-01

    Sleep duration has gradually diminished during the last decade while obesity and type 2 diabetes have become epidemics. Experimental sleep curtailment leads to increased appetite, hormonal disturbances and, especially, insulin resistance. Numerous epidemiological studies have therefore examined whether habitual short sleep is associated with obesity and type 2 diabetes. A large majority of cross-sectional studies have confirmed an association between short, and also long sleep duration and obesity in adults more than in the elderly. Short sleep is strongly associated to obesity in children and adolescents. Prospective studies, including studies in children, are not conclusive with regard to the effect of short sleep on the incidence of obesity. Both short and long sleep durations are associated with diabetes, but only short sleep duration seems predictive of future diabetes. Insomnia seems to be a strong contributor to short sleep duration but the association of insomnia with obesity is not clear. Insomnia is associated with type 2 diabetes and also predictive of a higher incidence. Other studies have shown that short sleep duration and insomnia are associated with, and sometime predictive of, other components of the metabolic syndrome, especially hypertension and the risk of coronary disease. The treatment of short sleep duration and insomnia with regard to their effects on the metabolic syndrome merits further study. PMID:26603959

  11. PULSE DURATION LENGTHENER

    DOEpatents

    Aiken, W.R.

    1958-02-01

    This patent pertains to pulse modifying apparatus and, more particularly, describes a device to provide a rise time and time base expander for signal pulses having a very short duration. The basic element of the device is a vacuum tube comprising a charged particie beam, grid control means, an accelerating electrode, a drift tube, and a collector electrode. As the short duration input pulse modulates the particle beam through the grid control means, the voltage between the drift tube and accelerating electrode is caused to vary, whereby the output signal from the collector is a pulse having longer rise time, expanded duration and proportionate characteristics of the original pulse. The invention is particuiarly useful where subsequent pulse circultry does not have the frequency bandwidth to handle the short duration pulse without distorting it.

  12. Electrocardiographic spatial QRS-T angle and incident cardiovascular disease in HIV-infected patients (from the Strategies for the Management of Antiretroviral Therapy [SMART] study).

    PubMed

    Dawood, Farah Z; Khan, Faraaz; Roediger, Mollie P; Zhang, Zhu-Ming; Swaminathan, Shobha; Klinker, Hartwig; Hoy, Jennifer; Lundgren, Jens D; Neaton, James D; Soliman, Elsayed Z

    2013-01-01

    Widening of the electrocardiographic (ECG) spatial QRS-T angle has been predictive of cardiovascular disease (CVD) events in the general population. However, its prognostic significance in human immunodeficiency virus (HIV)-infected patients remains unknown. The spatial QRS-T angle was derived from the baseline resting 12-lead electrocardiogram of 4,453 HIV-infected patients aged 43.5 ± 9.3 years from the Strategies for Management of Antiretroviral Therapy (SMART) trial. CVD events were identified during a median follow-up of 28.7 months. Quartiles of the spatial QRS-T angle was calculated for men and women separately, and values in the upper quartile were considered as a widened angle (values >74° for women and >93° for men). A multivariate Cox proportional hazards analysis was used to examine the association between a widened baseline spatial QRS-T angle and incident CVD events. During 11,965 person-years of follow-up, 152 CVD events occurred at a rate of 1.27 events/100 person-years. The rate of CVD events in those with a widened spatial QRS-T angle was almost double the rate in those with a normal spatial QRS-T angle (rate ratio 1.94, 95% confidence interval 1.40 to 2.69; p <0.001). In a model adjusted for study treatment arm, demographics, CVD risk factors, HIV characteristics, inflammatory markers, and other ECG abnormalities, a widened spatial QRS-T angle was associated with a >50% increased risk of CVD events compared to a normal spatial QRS-T angle (hazard ratio 1.53, 95% confidence interval 1.07 to 2.17; p = 0.02). No interaction was seen by SMART trial arm (p value for interaction = 0.37) or gender (p value for interaction = 0.84). In conclusion, a widened spatial QRS-T angle was independently predictive of CVD events in HIV-infected patients receiving antiretroviral therapy. This highlights the potential role of routine electrocardiography as a simple noninvasive CVD risk-screening tool in HIV-infected patients.

  13. Status epilepticus and wide-complex tachycardia secondary to diphenhydramine overdose

    PubMed Central

    JANG, DAVID H.; MANINI, ALEX F.; TRUEGER, NATHAN S.; DUQUE, DANNY; NESTOR, NESTOR B.; NELSON, LEWIS S.; HOFFMAN, ROBERT S.

    2014-01-01

    Objective Diphenhydramine is an H1 histamine antagonist that is commonly used for allergic reactions, colds and cough, and as a sleep aid. In addition to anticholinergic and antihistaminergic effects, sodium channel blockade becomes evident following diphenhydramine overdose. While seizures may occur following overdose of a diphenhydramine, status epilepticus is distinctly uncommon. We report a case with both status epilepticus and wide-complex dysrhythmias following an intentional diphenhydramine overdose. Case report A 36-year-old woman with a medical history of hypothyroidism on levothyroxine was brought to the emergency department with active seizures by emergency medical services after what was later determined to be a diphenhydramine overdose. One hour after an argument with her husband he found her lethargic in a locked room. Initial vital signs were: blood pressure, 90/55 mmHg; heart rate, 160 beats/min; respiratory rate 18 breaths/min; room air oxygen saturation, 99%; temperature, 99.8°F; rapid point-of-care glucose, 130 mg/dL. The generalized seizures continued for duration of 30 min, despite the intravenous administration of 8 mg of lorazepam. The patient underwent endotracheal intubation and a propofol infusion terminated her seizures. An electrocardiogram after the status was terminated which revealed a wide-complex tachycardia with QRS duration of 127 ms. The QRS narrowed after 200 mEq of intravenous sodium bicarbonate was administrated. The patient was neurologically intact upon extubation on hospital day 2. The serum diphenhydramine concentration drawn on arrival to the ED was 1200 ng/mL (9–120 ng/ mL); a tricyclic screen was negative. Discussion While seizures and sodium channel blockade are recognized complications of diphenhydramine toxicity, reported cases of status epilepticus from diphenhydramine overdose are rare. Elements of the patient’s presentation were similar to a tricyclic overdose and management required aggressive control of her

  14. The evaluation and management of drug effects on cardiac conduction (PR and QRS intervals) in clinical development.

    PubMed

    Nada, Adel; Gintant, Gary A; Kleiman, Robert; Gutstein, David E; Gottfridsson, Christer; Michelson, Eric L; Strnadova, Colette; Killeen, Matthew; Geiger, Mary Jane; Fiszman, Mónica L; Koplowitz, Luana Pesco; Carlson, Glenn F; Rodriguez, Ignacio; Sager, Philip T

    2013-04-01

    Recent advances in electrocardiographic monitoring and waveform analysis have significantly improved the ability to detect drug-induced changes in cardiac repolarization manifested as changes in the QT/corrected QT interval. These advances have also improved the ability to detect drug-induced changes in cardiac conduction. This White Paper summarizes current opinion, reached by consensus among experts at the Cardiac Safety Research Consortium, on the assessment of electrocardiogram-based safety measurements of the PR and QRS intervals, representing atrioventricular and ventricular conduction, respectively, during drug development.

  15. Word Durations in Non-Native English

    PubMed Central

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

    2010-01-01

    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

  16. Long Duration Sorbent Testbed

    NASA Technical Reports Server (NTRS)

    Howard, David F.; Knox, James C.; Long, David A.; Miller, Lee; Cmaric, Gregory; Thomas, John

    2016-01-01

    The Long Duration Sorbent Testbed (LDST) is a flight experiment demonstration designed to expose current and future candidate carbon dioxide removal system sorbents to an actual crewed space cabin environment to assess and compare sorption working capacity degradation resulting from long term operation. An analysis of sorbent materials returned to Earth after approximately one year of operation in the International Space Station's (ISS) Carbon Dioxide Removal Assembly (CDRA) indicated as much as a 70% loss of working capacity of the silica gel desiccant material at the extreme system inlet location, with a gradient of capacity loss down the bed. The primary science objective is to assess the degradation of potential sorbents for exploration class missions and ISS upgrades when operated in a true crewed space cabin environment. A secondary objective is to compare degradation of flight test to a ground test unit with contaminant dosing to determine applicability of ground testing.

  17. Myocardial contrast echocardiography (MCE) with triggered ultrasound does not cause premature ventricular complexes: evidence from PB127 MCE studies.

    PubMed

    Raisinghani, Ajit; Wei, Kevin S; Crouse, Linda; Villanueva, Floredeliza; Feigenbaum, Harvey; Schiller, Nelson B; Weiss, James; Naqvi, Tasneem Z; Siegel, Robert; Monaghan, Mark; Goldman, Jonathan H; Demaria, Anthony

    2003-10-01

    Previous studies suggest that myocardial contrast echocardiography using high mechanical index triggered ultrasound can be associated with increased frequency of the premature ventricular complex (PVC). However, this association has not been systematically examined. PB127 (Point Biomedical Corp, San Carlos, Calif) is a novel microsphere designed for evaluation of myocardial perfusion with ultrasound. PB127 myocardial contrast echocardiography was performed with triggered harmonic power Doppler in early/mid diastole (mechanical index complex frequency at baseline, during, and after infusion of PB127 (dose < 0.175 mg/kg, <60-minute duration). Proportions of triggered and nontriggered intervals associated with premature ventricular complex were determined. PVC frequency did not increase with PB127 infusion in either cohort (P =.572, P =.263). Proportion of triggered intervals after QRS associated with PVC was similar to proportion of untriggered intervals in cohort A (P >.999) and was lower than untriggered intervals (P =.001) in B, suggesting that triggers do not cause PVC. PB127 does not cause increase PVC frequency during or after imaging with triggered ultrasound at mechanical index of 1.

  18. Long duration ash probe

    DOEpatents

    Hurley, J.P.; McCollor, D.P.; Selle, S.J.

    1994-07-26

    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 soot blowing 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. 8 figs.

  19. Long duration ash probe

    DOEpatents

    Hurley, John P.; McCollor, Don P.; Selle, Stanley J.

    1994-01-01

    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.

  20. Striatal dynamics explain duration judgments

    PubMed Central

    Gouvêa, Thiago S; Monteiro, Tiago; Motiwala, Asma; Soares, Sofia; Machens, Christian; Paton, Joseph J

    2015-01-01

    The striatum is an input structure of the basal ganglia implicated in several time-dependent functions including reinforcement learning, decision making, and interval timing. To determine whether striatal ensembles drive subjects' judgments of duration, we manipulated and recorded from striatal neurons in rats performing a duration categorization psychophysical task. We found that the dynamics of striatal neurons predicted duration judgments, and that simultaneously recorded ensembles could judge duration as well as the animal. Furthermore, striatal neurons were necessary for duration judgments, as muscimol infusions produced a specific impairment in animals' duration sensitivity. Lastly, we show that time as encoded by striatal populations ran faster or slower when rats judged a duration as longer or shorter, respectively. These results demonstrate that the speed with which striatal population state changes supports the fundamental ability of animals to judge the passage of time. DOI: http://dx.doi.org/10.7554/eLife.11386.001 PMID:26641377

  1. Determinants of eye-fixation duration.

    PubMed

    Salthouse, T A; Ellis, C L

    1980-06-01

    Four variables that might be presumed to contribute to the duration of an eye fixation were investigated in a series of seven experiments. These variables were stimulus processing time, relative emphasis on speed or accuracy, sequential dependencies across successive fixations, and amplitude of the preceding and following saccades. The pattern of results suggested a two-component model to account for the duration of single eye-fixations. One component is the minimum pause time of the eye, estimated to be about 200 msec without any stimulus processing. The second component involves stimulus processing, estimated to require a minimum of 50 to 100 msec, but subject to a number of influences that can substantially increase or decrease this duration. Although the authors did not generate this model to account for eye movements in complex tasks such as reading, they speculate about how complications could be added.

  2. Premature Ventricular Complexes in Apparently Normal Hearts.

    PubMed

    Luebbert, Jeffrey; Auberson, Denise; Marchlinski, Francis

    2016-09-01

    Premature ventricular complexes (PVCs) are consistently associated with worse prognosis and higher morbidity and mortality. This article reviews PVCs and their presentation in patients with an apparently normal heart. Patients with PVCs may be completely asymptomatic, whereas others may note severely disabling symptoms. Cardiomyopathy may occur with frequent PVCs. Diagnostic work-up is directed at obtaining 12-lead ECG to characterize QRS morphology, Holter monitor to assess frequency, and echo and advanced imaging to assess for early cardiomyopathy and exclude structural heart disease. Options for management include watchful waiting, medical therapy, or catheter ablation. Malignant variants of PVCs may induce ventricular fibrillation even in a normal heart. PMID:27521085

  3. Extended Duration Orbiter Medical Project

    NASA Technical Reports Server (NTRS)

    Leach, C. S.; Pool, S. L.; Sawin, C. F.; Nicogossian, A. E.

    1990-01-01

    The Extended Duration Orbiter (EDO) program addresses a need for more time to perform experiments and other tasks during Space Shuttle missions. As a part of this program, the Extended Duration Orbiter Medical Project (EDOMP) has been instituted to obtain information about physiologic effects of extending mission duration and the effectiveness of countermeasures against factors that might compromise crew health, safety, or performance on extended-duration missions. Only those investigations that address and characterize operational problems, develop countermeasures, or evaluate the effectiveness of countermeasures will be pursued. The EDOMP investigations will include flight-associated Detailed Supplementary Objectives as well as ground-based studies simulating the influence of microgravity. Investigator teams have been formed in the following areas: biomedical physiology, cardiovascular and fluid/electrolyte physiology, environmental health, muscle and exercise physiology, and neurophysiology. Major operational questions must be answered in each of these areas, and investigations have been designed to answer them. The EDO program will proceed only after countermeasures have been shown to be effective in preventing or mitigating the adverse changes they have been designed to attenuate. The program is underway and will continue on each Shuttle flight as the manifest builds toward a 16-day orbital flight.

  4. Duration of an Elastic Collision

    ERIC Educational Resources Information Center

    de Izarra, Charles

    2012-01-01

    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…

  5. Effects of changes in frequency on guinea pig ventricular action potential duration and on QT interval under different experimental conditions.

    PubMed

    von Savigny, L; Hohnloser, S; Antoni, H

    1981-01-01

    Isolated perfused guinea pig hearts (Langendorff preparation) were arrested by carbachol (0.1-0.2 mg/l) and electrically stimulated in the region of the av-conducting system. The QT interval was determined by means of extracellular electrodes at different driving frequencies. Separate experiments were performed on papillary muscles from the right ventricle to measure the duration of the transmembrane action potential under comparable conditions. At 35 degrees C (Ke+ 5.4 mmol/l) increasing the frequency of stimulation (range 12-120/min) caused the action potential duration (APD) to decrease to a greater extent than the QT interval. Stepwise rising of the external K+ concentration up to 16.2 mmol/l produced a nearly parallel shift to the APD-frequency relation to lower values. Again, the QT interval was less affected by increasing the external K+ concentration than the APD. Stepwise reduction of the temperature down to 20 degrees C prolonged the APD as well as the QT interval, the effects being more pronounced at lower than at higher stimulation frequencies. Under all examined experimental conditions, the APD proved to be markedly shorter than the QT interval even when the latter is diminished by the duration of QRS. The results suggest that no close relation exists between the APD and the QT interval. The observed divergencies may be due to functional differences among various parts of the ventricles.

  6. Expected endings and judged duration.

    PubMed

    Jones, M R; Boltz, M G; Klein, J M

    1993-09-01

    In four experiments, the predictions of an expectancy/contrast model (Jones & Boltz, 1989) for judged duration were evaluated. In Experiments 1 and 2, listeners estimated the relative durations of auditory pattern pairs that varied in contextual phrasing and temporal contrast. The results showed that when the second pattern of a pair either seems to (Experiments 1 and 2) or actually does (Experiment 2) end earlier (later) than the first, subjects judge it as being relatively shorter (longer). In Experiment 3, listeners heard single patterns in which notes immediately preceding the final one were omitted. Timing of the final (target) tone was varied such that it was one beat early, on time, or one beat late. Listeners' ratings of target tones revealed systematic effects of phrasing and target timing. In Experiment 4, listeners temporally completed (extrapolated) sequences of Experiment 3 that were modified to exclude the target tone. The results again showed that phrase context systematically influenced expectancies about "when" sequences should end. As a set, these studies demonstrate the effects of event structure and anticipatory attending upon experienced duration and are discussed in terms of the expectancy/contrast model.

  7. Cohabitation Duration and Transient Domesticity.

    PubMed

    Golub, Andrew; Reid, Megan; Strickler, Jennifer; Dunlap, Eloise

    2013-01-01

    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.

  8. On a Possible Unified Scaling Law for Volcanic Eruption Durations

    NASA Astrophysics Data System (ADS)

    Cannavò, Flavio; Nunnari, Giuseppe

    2016-03-01

    Volcanoes constitute dissipative systems with many degrees of freedom. Their eruptions are the result of complex processes that involve interacting chemical-physical systems. At present, due to the complexity of involved phenomena and to the lack of precise measurements, both analytical and numerical models are unable to simultaneously include the main processes involved in eruptions thus making forecasts of volcanic dynamics rather unreliable. On the other hand, accurate forecasts of some eruption parameters, such as the duration, could be a key factor in natural hazard estimation and mitigation. Analyzing a large database with most of all the known volcanic eruptions, we have determined that the duration of eruptions seems to be described by a universal distribution which characterizes eruption duration dynamics. In particular, this paper presents a plausible global power-law distribution of durations of volcanic eruptions that holds worldwide for different volcanic environments. We also introduce a new, simple and realistic pipe model that can follow the same found empirical distribution. Since the proposed model belongs to the family of the self-organized systems it may support the hypothesis that simple mechanisms can lead naturally to the emergent complexity in volcanic behaviour.

  9. On a Possible Unified Scaling Law for Volcanic Eruption Durations.

    PubMed

    Cannavò, Flavio; Nunnari, Giuseppe

    2016-03-01

    Volcanoes constitute dissipative systems with many degrees of freedom. Their eruptions are the result of complex processes that involve interacting chemical-physical systems. At present, due to the complexity of involved phenomena and to the lack of precise measurements, both analytical and numerical models are unable to simultaneously include the main processes involved in eruptions thus making forecasts of volcanic dynamics rather unreliable. On the other hand, accurate forecasts of some eruption parameters, such as the duration, could be a key factor in natural hazard estimation and mitigation. Analyzing a large database with most of all the known volcanic eruptions, we have determined that the duration of eruptions seems to be described by a universal distribution which characterizes eruption duration dynamics. In particular, this paper presents a plausible global power-law distribution of durations of volcanic eruptions that holds worldwide for different volcanic environments. We also introduce a new, simple and realistic pipe model that can follow the same found empirical distribution. Since the proposed model belongs to the family of the self-organized systems it may support the hypothesis that simple mechanisms can lead naturally to the emergent complexity in volcanic behaviour.

  10. On a Possible Unified Scaling Law for Volcanic Eruption Durations.

    PubMed

    Cannavò, Flavio; Nunnari, Giuseppe

    2016-01-01

    Volcanoes constitute dissipative systems with many degrees of freedom. Their eruptions are the result of complex processes that involve interacting chemical-physical systems. At present, due to the complexity of involved phenomena and to the lack of precise measurements, both analytical and numerical models are unable to simultaneously include the main processes involved in eruptions thus making forecasts of volcanic dynamics rather unreliable. On the other hand, accurate forecasts of some eruption parameters, such as the duration, could be a key factor in natural hazard estimation and mitigation. Analyzing a large database with most of all the known volcanic eruptions, we have determined that the duration of eruptions seems to be described by a universal distribution which characterizes eruption duration dynamics. In particular, this paper presents a plausible global power-law distribution of durations of volcanic eruptions that holds worldwide for different volcanic environments. We also introduce a new, simple and realistic pipe model that can follow the same found empirical distribution. Since the proposed model belongs to the family of the self-organized systems it may support the hypothesis that simple mechanisms can lead naturally to the emergent complexity in volcanic behaviour. PMID:26926425

  11. On a Possible Unified Scaling Law for Volcanic Eruption Durations

    PubMed Central

    Cannavò, Flavio; Nunnari, Giuseppe

    2016-01-01

    Volcanoes constitute dissipative systems with many degrees of freedom. Their eruptions are the result of complex processes that involve interacting chemical-physical systems. At present, due to the complexity of involved phenomena and to the lack of precise measurements, both analytical and numerical models are unable to simultaneously include the main processes involved in eruptions thus making forecasts of volcanic dynamics rather unreliable. On the other hand, accurate forecasts of some eruption parameters, such as the duration, could be a key factor in natural hazard estimation and mitigation. Analyzing a large database with most of all the known volcanic eruptions, we have determined that the duration of eruptions seems to be described by a universal distribution which characterizes eruption duration dynamics. In particular, this paper presents a plausible global power-law distribution of durations of volcanic eruptions that holds worldwide for different volcanic environments. We also introduce a new, simple and realistic pipe model that can follow the same found empirical distribution. Since the proposed model belongs to the family of the self-organized systems it may support the hypothesis that simple mechanisms can lead naturally to the emergent complexity in volcanic behaviour. PMID:26926425

  12. Extended Duration Orbiter Medical Project

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  13. Icing Encounter Duration Sensitivity Study

    NASA Technical Reports Server (NTRS)

    Addy, Harold E., Jr.; Lee, Sam

    2011-01-01

    This paper describes a study performed to investigate how aerodynamic performance degradation progresses with time throughout an exposure to icing conditions. It is one of the first documented studies of the effects of ice contamination on aerodynamic performance at various points in time throughout an icing encounter. Both a 1.5 and 6 ft chord, two-dimensional, NACA-23012 airfoils were subjected to icing conditions in the NASA Icing Research Tunnel for varying lengths of time. At the end of each run, lift, drag, and pitching moment measurements were made. Measurements with the 1.5 ft chord model showed that maximum lift and pitching moment degraded more rapidly early in the exposure and degraded more slowly as time progressed. Drag for the 1.5 ft chord model degraded more linearly with time, although drag for very short exposure durations was slightly higher than expected. Only drag measurements were made with the 6 ft chord airfoil. Here, drag for the long exposures was higher than expected. Novel comparison of drag measurements versus an icing scaling parameter, accumulation parameter times collection efficiency was used to compare the data from the two different size model. The comparisons provided a means of assessing the level of fidelity needed for accurate icing simulation.

  14. Catheter ablation of a monofocal premature ventricular complex triggering idiopathic ventricular fibrillation.

    PubMed

    Takatsuki, S; Mitamura, H; Ogawa, S

    2001-07-01

    A 62 year old man was admitted for evaluation of recurrent episodes of syncope. A surface ECG showed frequent repetitive premature ventricular complexes of right ventricular outflow tract origin. Ventricular fibrillation was inducible by programmed electrical stimulation but otherwise cardiac evaluation was unremarkable. A diagnosis of idiopathic ventricular fibrillation was made and an implantable cardioverter-defibrillator (ICD) was installed. However, spontaneous ventricular fibrillation recurred, requiring repeated ICD discharges. The ventricular fibrillation was reproducibly triggered by a single premature ventricular complex with a specific QRS morphology. Radiofrequency catheter ablation was carried out to eradicate this complex. No ventricular fibrillation has developed after this procedure, and the patient does not require drug treatment.

  15. Visual duration aftereffect is position invariant

    PubMed Central

    Li, Baolin; Yuan, Xiangyong; Chen, Youguo; Liu, Peiduo; Huang, Xiting

    2015-01-01

    Adaptation to relatively long or short sensory events leads to a negative aftereffect, such that the durations of the subsequent events within a certain range appear to be contracted or expanded. The distortion in perceived duration is presumed to arise from the adaptation of duration detectors. Here, we focus on the positional sensitivity of those visual duration detectors by exploring whether the duration aftereffect may be constrained by the visual location of stimuli. We adopted two different paradigms, one that tests for transfer across visual hemifields, and the other that tests for simultaneous selectivity between visual hemifields. By employing these experimental designs, we show that the duration aftereffect strongly transfers across visual hemifields and is not contingent on them. The lack of position specificity suggests that duration detectors in the visual system may operate at a relatively later stage of sensory processing. PMID:26500591

  16. Duration perception in crossmodally-defined intervals.

    PubMed

    Mayer, Katja M; Di Luca, Massimiliano; Ernst, Marc O

    2014-03-01

    How humans perform duration judgments with multisensory stimuli is an ongoing debate. Here, we investigated how sub-second duration judgments are achieved by asking participants to compare the duration of a continuous sound to the duration of an empty interval in which onset and offset were marked by signals of different modalities using all combinations of visual, auditory and tactile stimuli. The pattern of perceived durations across five stimulus durations (ranging from 100 ms to 900 ms) follows the Vierordt Law. Furthermore, intervals with a sound as onset (audio-visual, audio-tactile) are perceived longer than intervals with a sound as offset. No modality ordering effect is found for visualtactile intervals. To infer whether a single modality-independent or multiple modality-dependent time-keeping mechanisms exist we tested whether perceived duration follows a summative or a multiplicative distortion pattern by fitting a model to all modality combinations and durations. The results confirm that perceived duration depends on sensory latency (summative distortion). Instead, we did not find evidence for multiplicative distortions. The results of the model and the behavioural data support the concept of a single time-keeping mechanism that allows for judgments of durations marked by multisensory stimuli. PMID:23953664

  17. Duration tuning in the mouse auditory midbrain.

    PubMed

    Brand, A; Urban, R; Grothe, B

    2000-10-01

    Temporal cues, including sound duration, are important for sound identification. Neurons tuned to the duration of pure tones were first discovered in the auditory system of frogs and bats and were discussed as specific adaptations in these animals. More recently duration sensitivity has also been described in the chinchilla midbrain and the cat auditory cortex, indicating that it might be a more general phenomenon than previously thought. However, it is unclear whether duration tuning in mammals is robust in face of changes of stimulus parameters other than duration. Using extracellular single-cell recordings in the mouse inferior colliculus, we found 55% of cells to be sensitive to stimulus duration showing long-pass, short-pass, or band-pass filter characteristics. For most neurons, a change in some other stimulus parameter, (e.g., intensity, frequency, binaural conditions, or using noise instead of pure tones) altered and sometimes abolished duration-tuning characteristics. Thus in many neurons duration tuning is interdependent with other stimulus parameters and, hence, might be context dependent. A small number of inferior colliculus neurons, in particular band-pass neurons, exhibited stable filter characteristics and could therefore be referred to as "duration selective." These findings support the idea that duration tuning is a general phenomenon in the mammalian auditory system.

  18. Training for long duration space missions

    NASA Technical Reports Server (NTRS)

    Goldberg, Joseph H.

    1987-01-01

    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.

  19. An optimization principle for determining movement duration.

    PubMed

    Tanaka, Hirokazu; Krakauer, John W; Qian, Ning

    2006-06-01

    Movement duration is an integral component of motor control, but nearly all extant optimization models of motor planning prefix duration instead of explaining it. Here we propose a new optimization principle that predicts movement duration. The model assumes that the brain attempts to minimize movement duration under the constraint of meeting an accuracy criterion. The criterion is task and context dependent but is fixed for a given task and context. The model determines a unique duration as a trade-off between speed (time optimality) and accuracy (acceptable endpoint scatter). We analyzed the model for a linear motor plant, and obtained a closed-form equation for determining movement duration. By solving the equation numerically with specific plant parameters for the eye and arm, we found that the model can reproduce saccade duration as a function of amplitude (the main sequence), and arm-movement duration as a function of the ratio of target distance to size (Fitts's law). In addition, it explains the dependency of peak saccadic speed on amplitude and the dependency of saccadic duration on initial eye position. Furthermore, for arm movements, the model predicts a scaling relationship between peak velocity and distance and a reduction in movement duration with a moderate increase in viscosity. Finally, for a linear plant, our model predicts a neural control signal identical to that of the minimum-variance model set to the same movement duration. This control signal is a smooth function of time (except at the endpoint), in contrast to the discontinuous bang-bang control found in the time-optimal control literature. We suggest that one aspect of movement planning, as revealed by movement duration, may be to assign an endpoint accuracy criterion for a given task and context. PMID:16571740

  20. 5 CFR 890.1302 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... EMPLOYEES HEALTH BENEFITS PROGRAM Department of Defense Federal Employees Health Benefits Program Demonstration Project § 890.1302 Duration. The demonstration project will run from January 1, 2000,...

  1. 5 CFR 330.1102 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PLACEMENT (GENERAL) Federal Employment Priority Consideration Program for Displaced Employees of the District of Columbia Department of Corrections § 330.1102 Duration. This program terminates 1 year...

  2. Botulinum toxin: examining duration of effect in facial aesthetic applications.

    PubMed

    Flynn, Timothy Corcoran

    2010-01-01

    durations of response. Across all studies providing relapse rates, most patients relapsed by 6 months. In studies assessing patient satisfaction, satisfaction remained high throughout the duration of the studies ( approximately 4 months). With the Dysport formulation (abobotulinumtoxinA, clostridium botulinum type A toxin-hemagglutinin complex; Ipsen Biopharm Ltd, Wrexham, England), retreatment intervals were estimated at a mean of 3.9 months (median = 3.3 months). These results were consistent with responder rates from another Dysport study in which the active treatment differed from placebo at 3 but not 4 months. A single comparative study demonstrated that the proportion of patients relapsing at week 16 was 23% (95% CI 11.5, 41.6) in the BOTOX Cosmetic group as compared with 40% (95% CI 25.2, 60.1) in the Dysport group. Myobloc (rimabotulinumtoxinB, botulinum toxin type B; Solstice Neurosciences, Inc., South San Francisco, CA, USA) was associated with shorter durations of action (2-3 months). Data from facial areas other than the glabella, although more limited, supported a duration of at least 3-4 months. The addition of BoNTA to dermal fillers or light/laser therapy appeared to increase the degree of effect. Repeated BoNTA treatments may prolong duration of effect or potentiate the effect. In conclusion, patients can expect treatments to last > or =3 months but often as many as 4-5 months depending on the facial area, dose, and formulation. Additional research should help clarify the impact of age, baseline rhytid severity, patient sex, repeated treatments, and combination treatment on longevity of effect. PMID:20369902

  3. Health care delivery system for long duration manned space operations

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    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.

  4. Repair of Electronics for Long Duration Spaceflight

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

    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

  5. Electrocardiogram of Clinically Healthy Mithun (Bos frontalis): Variation among Strains.

    PubMed

    Sanyal, Sagar; Das, Pradip Kumar; Ghosh, Probal Ranjan; Das, Kinsuk; Vupru, Kezha V; Rajkhowa, Chandan; Mondal, Mohan

    2010-09-22

    A study was conducted to establish the normal electrocardiogram in four different genetic strains of mithun (Bos frontalis). Electrocardiography, cardiac electrical axis, heart rate, rectal temperature and respiration rate were recorded in a total of 32 adult male mithun of four strains (n = 8 each). It was found that the respiration and heart rates were higher (P < .05) in Manipur than other three strains. Amplitude (P < .05) and duration of P wave and QRS complex differed (P < .01) among the strains. Mizoram strain had the highest amplitude and duration of P wave and QRS complex. On the other hand, higher (P < .05) amplitude and duration of T wave were recorded in Arunachalee and Mizoram strains. The mean electrical axis of QRS complex that were recorded for Arunachalee and Manipur strains were similar to that reported for other bovine species; whereas the electrical axis of QRS for Nagamese and Mizoram strains were more close to feline and caprine species, respectively. In conclusion, electrocardiogram of mithun revealed that the amplitude and duration of P wave, QRS complex and T wave were different among four different genetic strains of mithun and the electrical axis of QRS complex for Nagamese and Mizoram mithuns are dissimilar to bovine species.

  6. 7 CFR 550.6 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Duration. 550.6 Section 550.6 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE GENERAL ADMINISTRATIVE POLICY FOR NON-ASSISTANCE COOPERATIVE AGREEMENTS General § 550.6 Duration. REE...

  7. 7 CFR 550.6 - Duration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Duration. 550.6 Section 550.6 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE GENERAL ADMINISTRATIVE POLICY FOR NON-ASSISTANCE COOPERATIVE AGREEMENTS General § 550.6 Duration. REE...

  8. Stimulus Intensity and the Perception of Duration

    ERIC Educational Resources Information Center

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

    2011-01-01

    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…

  9. Wound duration and healing rates: cause or effect?

    PubMed

    Bosanquet, David C; Harding, Keith G

    2014-01-01

    Multiple factors affect the likelihood of a wound healing. One of these factors, wound duration, is well known to be related to healing rates, with numerous publications showing that older wounds are less likely to heal. However, disentangling the effect of this factor on wound healing rates is complex. Is this simply an observation of the obvious; wounds of longer duration will by definition be harder to heal? Or does time represent an independent factor, implying that should treatments be given earlier in the disease process, better outcomes may result? This review summarizes the available evidence of the effects of wound duration on healing rates and examines potential biological aberrations identified in chronic wounds, which may be significant in making chronic wounds difficult to heal. Wounds of longer duration are associated with excessive inflammation, fibroblast senescence, and alterations in wound bed flora, which appears to have a temporal relationship. Early and aggressive treatment of ulcers that fail to respond to standard care may well aid in reducing the burden of wounds that become chronic.

  10. Repetition enhancement and memory effects for duration.

    PubMed

    Wiener, Martin; Thompson, James C

    2015-06-01

    A remarkable aspect of conscious perception is that moments carryover from one to the next, also known as temporal continuity. This ability is thus crucial for detecting regularities, such as in speech and music, and may rely on an accurate perception of time. Investigations of human time perception have detailed two electroencephalographic (EEG) components associated with timing, the contingent negative variation (CNV) and late positive component of timing (LPCt); however, the precise roles of these components in timing remain elusive. Recently, we demonstrated that the perception of duration is influenced by durations presented on prior trials, which we explained by the creation of an implicit memory standard that adapts to local changes in sequence presentation. Here, we turn to the neural basis of this effect. Human participants performed a temporal bisection task in which they were required to classify the duration of auditory stimuli into short and long duration categories; crucially, the presentation order was first-order counterbalanced, allowing us to measure the effect of each presented duration on the next. EEG recordings revealed that the CNV and LPCt signals both covaried with the duration presented on the current trial, with CNV predicting reaction time and LPCt predicting choice. Additionally, both signals covaried with the duration presented in the prior trial but in different ways, with the CNV amplitude reflecting the change in the memory standard and the LPCt reflecting decision uncertainty. Furthermore, we observed a repetition enhancement effect of duration only for the CNV, suggesting that this signal additionally indexes the similarity of successive durations. These findings demonstrate dissociable roles for the CNV and LPCt, and demonstrate that both signals are continuously updated on a trial-by-trial basis that reflects shifts in temporal decisions. PMID:25818689

  11. Repetition enhancement and memory effects for duration.

    PubMed

    Wiener, Martin; Thompson, James C

    2015-06-01

    A remarkable aspect of conscious perception is that moments carryover from one to the next, also known as temporal continuity. This ability is thus crucial for detecting regularities, such as in speech and music, and may rely on an accurate perception of time. Investigations of human time perception have detailed two electroencephalographic (EEG) components associated with timing, the contingent negative variation (CNV) and late positive component of timing (LPCt); however, the precise roles of these components in timing remain elusive. Recently, we demonstrated that the perception of duration is influenced by durations presented on prior trials, which we explained by the creation of an implicit memory standard that adapts to local changes in sequence presentation. Here, we turn to the neural basis of this effect. Human participants performed a temporal bisection task in which they were required to classify the duration of auditory stimuli into short and long duration categories; crucially, the presentation order was first-order counterbalanced, allowing us to measure the effect of each presented duration on the next. EEG recordings revealed that the CNV and LPCt signals both covaried with the duration presented on the current trial, with CNV predicting reaction time and LPCt predicting choice. Additionally, both signals covaried with the duration presented in the prior trial but in different ways, with the CNV amplitude reflecting the change in the memory standard and the LPCt reflecting decision uncertainty. Furthermore, we observed a repetition enhancement effect of duration only for the CNV, suggesting that this signal additionally indexes the similarity of successive durations. These findings demonstrate dissociable roles for the CNV and LPCt, and demonstrate that both signals are continuously updated on a trial-by-trial basis that reflects shifts in temporal decisions.

  12. A progressive-duration schedule of reinforcement.

    PubMed

    Gulotta, Kara B; Byrne, Tom

    2015-12-01

    We describe a schedule of reinforcement involving systematic, within-session increases in response-duration requirements. Rats received access to appetitive reinforcers for depressing and holding down a response lever. Duration requirements increased after each reinforcer delivery. Sessions ended when reinforcement criteria were unmet for a period of ten minutes. Breaking points, defined as the terminal duration requirement in effect prior to the end of the session, stabilized when environmental conditions were held constant. Breaking points were sensitive to manipulations of both food deprivation and reinforcer quality. Analogous to progressive-ratio schedules, progressive-duration schedules may provide an assay for measuring the amount of behavior an organism will emit for a given reinforcer under current motivational conditions.

  13. [Duration of antibiotic therapy in bacterial meningitis].

    PubMed

    Pereira, P Ricardo; Borges, Fernando; Mansinho, Kamal

    2013-01-01

    The duration of antibiotic therapy in bacterial meningitis is a controversial issue. Antibiotic regimens have changed over time along with the criteria used to determine the ideal antibiotic therapy duration. The authors aim to make an historical overview on this matter and simultaneously add the evidence of recent studies, pointing out some issues in results interpretation, namely, their design and the associated demographic and epidemiological questions. Clinical assays on this subject, with statistically significant results, are quite recent. Most of the scientific knowledge has been acquired empirically through the times. The actual investigation paradigm, in what concerns to antibiotic therapy in bacterial meningitis, lays on the dichotomy: "short versus long duration regimens". Nevertheless, so far, the existing studies have not completely cleared this doubt. Thus, despite some evidence suggests that short duration antibiotic regimens are effective for some patients, in patients with severe disease presentations or with other morbidities its use may be questioned.

  14. Rainfall intensity-duration-frequency formulas.

    USGS Publications Warehouse

    Chen, C.-L.

    1983-01-01

    A new general rainfall intensity-duration-frequency formula is presented, utilizing a method similar to, but more accurate than one previously developed. The previously developed formula was based on the average depth-duration ratio of about 40% and the mean depth-frequency ratio of 1.48. It is shown that this formula is only a particular form of the writer's more general formulation. -from Author

  15. Collective behaviors of book holding durations

    NASA Astrophysics Data System (ADS)

    Li, Ren-De; Guo, Qiang; Han, Jing-Ti; Liu, Jian-Guo

    2016-10-01

    Duration can directly reflect the collective reading behaviors of library user book holding. In this paper, by introducing the burstiness and memory coefficients, we empirically investigate the collective book holding behavior of three university libraries. The statistical results show that there are similar properties among the students with different backgrounds, presenting the burstiness < B > = - 0.2 and memory < M > = 0.5 for three datasets, which indicates that memory and random effects coexist in student book holding durations. In addition, we analyze the behavior patterns without duplicate durations by merging a series of books borrowed and returned at the same time. The results show the average burstiness B increases to -0.16 and memory M drops to 0.16 for three datasets, which indicates that both duplicate behavior and student's preference affect the memory effect. Furthermore, we present a model which assumes student's next book holding duration follows the previous one with probability p, and with probability 1 - p, the student would hold the book independently. The experimental results show that the presented model can reproduce the burstiness and memory effect of student book holding durations when p = 0.5 for empirical datasets and p = 0.2 for de-duplicate datasets, which indicate that the student's preferential holding behavior occurs with the probability p. This work helps in deeply understanding the regularity of duration-based human behaviors.

  16. Effects of pulse duration on magnetostimulation thresholds

    PubMed Central

    Saritas, Emine U.; Goodwill, Patrick W.; Conolly, Steven M.

    2015-01-01

    Purpose: Medical imaging techniques such as magnetic resonance imaging and magnetic particle imaging (MPI) utilize time-varying magnetic fields that are subject to magnetostimulation limits, which often limit the speed of the imaging process. Various human-subject experiments have studied the amplitude and frequency dependence of these thresholds for gradient or homogeneous magnetic fields. Another contributing factor was shown to be number of cycles in a magnetic pulse, where the thresholds decreased with longer pulses. The latter result was demonstrated on two subjects only, at a single frequency of 1.27 kHz. Hence, whether the observed effect was due to the number of cycles or due to the pulse duration was not specified. In addition, a gradient-type field was utilized; hence, whether the same phenomenon applies to homogeneous magnetic fields remained unknown. Here, the authors investigate the pulse duration dependence of magnetostimulation limits for a 20-fold range of frequencies using homogeneous magnetic fields, such as the ones used for the drive field in MPI. Methods: Magnetostimulation thresholds were measured in the arms of six healthy subjects (age: 27 ± 5 yr). Each experiment comprised testing the thresholds at eight different pulse durations between 2 and 125 ms at a single frequency, which took approximately 30–40 min/subject. A total of 34 experiments were performed at three different frequencies: 1.2, 5.7, and 25.5 kHz. A solenoid coil providing homogeneous magnetic field was used to induce stimulation, and the field amplitude was measured in real time. A pre-emphasis based pulse shaping method was employed to accurately control the pulse durations. Subjects reported stimulation via a mouse click whenever they felt a twitching/tingling sensation. A sigmoid function was fitted to the subject responses to find the threshold at a specific frequency and duration, and the whole procedure was repeated at all relevant frequencies and pulse durations

  17. Effects of pulse duration on magnetostimulation thresholds

    SciTech Connect

    Saritas, Emine U.; Goodwill, Patrick W.; Conolly, Steven M.

    2015-06-15

    Purpose: Medical imaging techniques such as magnetic resonance imaging and magnetic particle imaging (MPI) utilize time-varying magnetic fields that are subject to magnetostimulation limits, which often limit the speed of the imaging process. Various human-subject experiments have studied the amplitude and frequency dependence of these thresholds for gradient or homogeneous magnetic fields. Another contributing factor was shown to be number of cycles in a magnetic pulse, where the thresholds decreased with longer pulses. The latter result was demonstrated on two subjects only, at a single frequency of 1.27 kHz. Hence, whether the observed effect was due to the number of cycles or due to the pulse duration was not specified. In addition, a gradient-type field was utilized; hence, whether the same phenomenon applies to homogeneous magnetic fields remained unknown. Here, the authors investigate the pulse duration dependence of magnetostimulation limits for a 20-fold range of frequencies using homogeneous magnetic fields, such as the ones used for the drive field in MPI. Methods: Magnetostimulation thresholds were measured in the arms of six healthy subjects (age: 27 ± 5 yr). Each experiment comprised testing the thresholds at eight different pulse durations between 2 and 125 ms at a single frequency, which took approximately 30–40 min/subject. A total of 34 experiments were performed at three different frequencies: 1.2, 5.7, and 25.5 kHz. A solenoid coil providing homogeneous magnetic field was used to induce stimulation, and the field amplitude was measured in real time. A pre-emphasis based pulse shaping method was employed to accurately control the pulse durations. Subjects reported stimulation via a mouse click whenever they felt a twitching/tingling sensation. A sigmoid function was fitted to the subject responses to find the threshold at a specific frequency and duration, and the whole procedure was repeated at all relevant frequencies and pulse durations

  18. Microcontroller uses in Long-Duration Ballooning

    NASA Astrophysics Data System (ADS)

    Jones, Joseph

    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

  19. Estimating magnitude and duration of incident delays

    SciTech Connect

    Garib, A.; Radwan, A.E.; Al-Deek, H.

    1997-11-01

    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).

  20. Duration expansion at low luminance levels.

    PubMed

    Bruno, Aurelio; Ayhan, Inci; Johnston, Alan

    2011-01-01

    Duration distortions have been shown to occur at the time of saccades and following high temporal frequency or contrast adaptation. Under all these conditions, changes in the temporal tuning of M neurons also occur, suggesting that there might be a link between the two phenomena. In order to explore this relationship further, we measured the apparent duration of visual stimuli in the dark, where the temporal impulse response has been reported to lengthen. We first measured a progressive shift and reduction of the occurrence of an apparent motion reversal as we decreased the luminance level, indicating a lengthening of the temporal impulse response. We then measured perceived duration at these luminance levels (0.75, 3, and 50 cd/m(2)) after matching for apparent contrast and temporal frequency. While perceived temporal frequency did not substantially differ across luminance levels, duration appeared expanded at the lowest luminance level relative to the highest by approximately 60 ms. Thus, we have shown that reduced luminance is associated with both a lengthening of the temporal impulse response and a duration expansion, linking the two and providing further evidence for a relationship between changes in the neuronal tuning in the early stages of the visual system and time perception.

  1. STS mission duration enhancement study: (orbiter habitability)

    NASA Technical Reports Server (NTRS)

    Carlson, A. D.

    1979-01-01

    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.

  2. Fluctuation behaviors of financial return volatility duration

    NASA Astrophysics Data System (ADS)

    Niu, Hongli; Wang, Jun; Lu, Yunfan

    2016-04-01

    It is of significantly crucial to understand the return volatility of financial markets because it helps to quantify the investment risk, optimize the portfolio, and provide a key input of option pricing models. The characteristics of isolated high volatility events above certain threshold in price fluctuations and the distributions of return intervals between these events arouse great interest in financial research. In the present work, we introduce a new concept of daily return volatility duration, which is defined as the shortest passage time when the future volatility intensity is above or below the current volatility intensity (without predefining a threshold). The statistical properties of the daily return volatility durations for seven representative stock indices from the world financial markets are investigated. Some useful and interesting empirical results of these volatility duration series about the probability distributions, memory effects and multifractal properties are obtained. These results also show that the proposed stock volatility series analysis is a meaningful and beneficial trial.

  3. Slow Wave Sleep and Long Duration Spaceflight

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

    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.

  4. 20 CFR 336.3 - Duration of normal sickness benefits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Duration of normal sickness benefits. 336.3... INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal sickness benefits. The duration of normal sickness benefits is the same as the duration of normal...

  5. 20 CFR 336.3 - Duration of normal sickness benefits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Duration of normal sickness benefits. 336.3... INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal sickness benefits. The duration of normal sickness benefits is the same as the duration of normal...

  6. 20 CFR 336.3 - Duration of normal sickness benefits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Duration of normal sickness benefits. 336.3... INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal sickness benefits. The duration of normal sickness benefits is the same as the duration of normal...

  7. 20 CFR 336.3 - Duration of normal sickness benefits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Duration of normal sickness benefits. 336.3... INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal sickness benefits. The duration of normal sickness benefits is the same as the duration of normal...

  8. 20 CFR 336.3 - Duration of normal sickness benefits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Duration of normal sickness benefits. 336.3... INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.3 Duration of normal sickness benefits. The duration of normal sickness benefits is the same as the duration of normal...

  9. Slow Wave Sleep and Long Duration Spaceflight

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

    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).

  10. Chronotype and sleep duration: the influence of season of assessment.

    PubMed

    Allebrandt, Karla V; Teder-Laving, Maris; Kantermann, Thomas; Peters, Annette; Campbell, Harry; Rudan, Igor; Wilson, James F; Metspalu, Andres; Roenneberg, Till

    2014-06-01

    Little is known about human entrainment under natural conditions, partly due to the complexity of human behavior, torn between biological and social time and influenced by zeitgebers (light-dark cycles) that are progressively "polluted" (and thereby weakened) by artificial light. In addition, data about seasonal variations in sleep parameters are scarce. We, therefore, investigated seasonal variation in cross-sectional assessments of sleep/wake times of 9765 subjects from four European populations (EGCUT = Estonian Genome Centre, University of Tartu in Estonia; KORA = Cooperative Health Research in the Region of Augsburg in Germany; KORCULA = The Korcula study in Croatia; and ORCADES = The Orkney Complex Disease Study in Scotland). We identified time-of-year dependencies for the distribution of chronotype (phase of entrainment assessed as the mid-sleep time point on free days adjusted for sleep deficit of workdays) in cohorts from Estonia (EGCUT) and Germany (KORA). Our results indicate that season (defined as daylight saving time - DST and standard zonetime periods - SZT) specifications of photoperiod influence the distribution of chronotype (adjusted for age and sex). Second, in the largest investigated sample, from Estonia (EGCUT; N = 5878), we could detect that seasonal variation in weekly average sleep duration was dependent on individual chronotype. Later chronotypes in this cohort showed significant variation in their average sleep duration across the year, especially during DST (1 h advance in social time from the end of March to end of October), while earlier chronotypes did not. Later chronotypes not only slept less during the DST period but the average chronotype of the population assessed during this period was earlier than during the SZT (local time for a respective time zone) period. More in detail, hierarchical multiple regression analyses showed that, beyond season of assessment (DST or SZT), social jetlag (SJl; the discrepancy

  11. LONG-DURATION LOW-FREQUENCY TYPE III BURSTS AND SOLAR ENERGETIC PARTICLE EVENTS

    SciTech Connect

    Gopalswamy, Nat; Maekelae, Pertti

    2010-09-20

    We analyzed the coronal mass ejections (CMEs), flares, and type II radio bursts associated with a set of three complex, long-duration, low-frequency (<14 MHz) type III bursts from active region 10588 in 2004 April. The durations were measured at 1 and 14 MHz using data from Wind/WAVES and were well above the threshold value (>15 minutes) normally used to define these bursts. One of the three type III bursts was not associated with a type II burst, which also lacked a solar energetic particle (SEP) event at energies >25 MeV. The 1 MHz duration of the type III burst (28 minutes) for this event was near the median value of type III durations found for gradual SEP events and ground level enhancement events. Yet, there was no sign of an SEP event. On the other hand, the other two type III bursts from the same active region had similar duration but were accompanied by WAVES type II bursts; these bursts were also accompanied by SEP events detected by SOHO/ERNE. The CMEs for the three events had similar speeds, and the flares also had similar size and duration. This study suggests that the occurrence of a complex, long-duration, low-frequency type III burst is not a good indicator of an SEP event.

  12. Sleep Duration and Breast Cancer Phenotype

    PubMed Central

    Khawaja, Ali; Rao, Santosh; Li, Li; Thompson, Cheryl L.

    2013-01-01

    Emerging evidence suggests that short sleep is associated with an increased risk of cancer; however, little has been done to study the role of sleep on tumor characteristics. In this study, we evaluated the relationship between sleep duration and tumor phenotype in 972 breast cancer patients. Sleep duration was inversely associated with tumor grade (univariate P = 0.032), particularly in postmenopausal women (univariate P = 0.018). This association did not reach statistical significance after adjustments for age, race, body mass index, hormone replacement therapy use, alcohol consumption, smoking, and physical activity in the entire study sample (P = 0.052), but it remained statistically significant (P = 0.049) among post-menopausal patients. We did not observe a statistically significant association between sleep duration and stage at diagnosis, ER, or HER2 receptor status. These results present a modest association between short duration of sleep and higher grade breast cancer in post-menopausal women. Further work needs to be done to validate these findings. PMID:24319459

  13. Duration and Intensity as Correlates of Fo.

    ERIC Educational Resources Information Center

    Zee, Eric

    1978-01-01

    The speech of two male Taiwanese speakers was analyzed to determine whether fundamental frequency (Fo) is correlated with both duration and intensity; five conclusions are drawn. The results are discussed in terms of theories of pitch production and speed of pitch change. (EJS)

  14. Breathhold duration and response to marijuana smoke.

    PubMed

    Zacny, J P; Chait, L D

    1989-06-01

    Marijuana smokers are frequently observed to hold the smoke in their lungs for prolonged periods (10-15 sec) apparently in the belief that prolonged breathholding intensifies the effects of the drug. The actual influence of breathhold duration on response to marijuana smoke has not been studied. The present study examined the effects of systematic manipulation of breathhold duration on the physiological, cognitive and subjective response to marijuana smoke in a group of eight regular marijuana smokers. Subjects were exposed to each of three breathhold duration conditions (0, 10 and 20 sec) on three occasions, scheduled according to a randomized block design. A controlled smoking procedure was used in which the number of puffs, puff volume and postpuff inhalation volume were held constant. Expired air carbon monoxide levels were measured before and after smoking to monitor smoke intake. Typical marijuana effects (increased heart rate, increased ratings of "high" and impaired memory performance) were observed under each of the breathhold conditions, but there was little evidence that response to marijuana was a function of breathhold duration.

  15. Developmental Aspects of English Segment Duration.

    ERIC Educational Resources Information Center

    Smith, Bruce L.

    The experiment reported here attempted to investigate the nature of both intrinsic, unlearned temporal parameters as well as learned, language-specific durational properties in the speech of young children. Developmental aspects of several temporal parameters were investigated in the speech of ten 2 1/2 to 3-year-old and ten 4 to 4 1/2-year-old…

  16. Short-Duration Simulations from Measurements.

    SciTech Connect

    Mitchell, Dean J.; Enghauser, Michael

    2014-08-01

    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.

  17. Does oseltamivir shorten flu symptom duration?

    PubMed

    Broadhurst, Richard; Mounsey, Anne

    2016-08-01

    Treatment of influenza virus infection with oral oseltamivir reduces time to alleviation of symptoms in adults and children by approximately one day compared with placebo. It reduces symptom duration even when initiated more than 2 days after symptom onset. PMID:27660842

  18. long duration dust storm sequences on Mars

    NASA Astrophysics Data System (ADS)

    Wang, H.

    2012-12-01

    The Mars Global Surveyor (MGS) Mars Observer Camera (MOC) and Mars Reconnaissance Orbiter (MRO) Mars Color Imager (MARCI) Mars daily global maps have revealed new characteristics for long duration dust storm sequences. These dust storm sequences have long histories of more than a week, travel long distances out of their origination region, and influence large areas in different regions of the planet. During the Ls = 180 - 360 season, except for global dust storms which involve multiple remote dust lifting centers and generally expand explosively from the southern hemisphere northward, other long-lived dust storm sequences usually travel southward through the Acidalia-Chryse, Utopia-Isidis or Arcadia-Amazonis channels with subsequent dust lifting along the way. Sometimes, they penetrate remarkably deep to the southern high latitudes, producing fantastic display of dust band. During the rest of the year, long duration dust storm sequences usually originate from the Argyre/Solis, Hellas/Noachis, or Cimmeria/Sirenum area and travel northward toward the southern low latitudes. Each route exhibits its own peculiar characteristics. We will present our results about these long duration dust storm sequences summarized from the complete archive of MGS MOC daily global maps and two years of MRO MARCI daily global maps. The systematic daily nearly global coverage of these maps makes it feasible to reconstruct the history of long duration dust storm sequences with detail.

  19. Childhood Sleep Duration and Lifelong Mortality Risk

    PubMed Central

    Duggan, Katherine A.; Reynolds, Chandra A.; Kern, Margaret L.; Friedman, Howard S.

    2014-01-01

    Objective Sleep duration is known to significantly affect health in adults and children, but little is understood about long-term associations. This prospective cohort study is the first to examine whether childhood sleep duration is associated with lifelong mortality risk. Methods Data from childhood were refined and mortality data collected for 1,145 participants from the Terman Life Cycle Study. Participants were born between 1904 and 1915, lived to at least 1940, and had complete age, bedtime, and waketime data at initial data collection (1917–1926). Homogeneity of the cohort sample (intelligent, mostly white) limits generality but provides natural control of common confounds. Through 2009, 1,039 participants had confirmed deaths. Sleep duration was calculated as the difference between each child’s bed and wake times. Age-adjusted sleep (deviation from that predicted by age) was computed. Cox proportional hazards survival models evaluated childhood sleep duration as a predictor of mortality separately by sex, controlling for baseline age. Results For males, a quadratic relation emerged: male children who under-slept or over-slept compared to peers were at increased risk of lifelong all-cause mortality (HR = 1.15, CI = 1.05 – 1.27). Effect sizes were smaller and non-significant in females (HR = 1.02, CI = 0.91 – 1.14). Conclusions Male children with shorter or longer sleep durations than expected for their age were at increased risk of death at any given age in adulthood. The findings suggest that sleep may be a core biobehavioral trait, with implications for new models of sleep and health throughout the entire lifespan. PMID:24588628

  20. Narrow-QRS and Wide-QRS Tachycardias.

    PubMed

    Glancy, David Luke

    2016-07-01

    In a woman with rheumatic heart disease, atrial flutter with a rapid ventricular response, and congestive heart failure, treatment with digoxin slows conduction in the atrioventricular node and thus allows atrioventricular conduction to occur by way of a previously unrecognized accessory pathway. PMID:27178329

  1. Power Systems Design for Long Duration Ballooning

    NASA Technical Reports Server (NTRS)

    Stilwell, Bryan; Chuzel, Alain

    2016-01-01

    The Columbia Scientific Balloon Facility has been designing and building high-altitude balloon power systems for over 26 years. With that experience, we have found certain types of PV panels, batteries, and charge controllers that are reliable in stratospheric environments. The ultimate goal is to ensure that power systems will provide power reliably throughout the duration of an LDB flight. The purpose of this presentation is to provide some general guidelines and best practices for power system design.

  2. Temporal integration in duration and number discrimination.

    PubMed

    Meck, W H; Church, R M; Gibbon, J

    1985-10-01

    Temporal integration in duration and number discrimination by rats was investigated with the use of a psychophysical choice procedure. A response on one lever ("short" response) following a 1-s white-noise signal was followed by food reinforcement, and a response on the other lever ("long" response) following a 2-s white-noise signal was also followed by food reinforcement. Either response following a signal of one of five intermediate durations was unreinforced. This led to a psychophysical function in which the probability of a long response was related to signal duration in an ogival manner. On 2 test days, a white-noise signal with 5, 6, 7, 8, or 10 segments of either 0.5-s on and 0.5-s off or 1-s on and 1-s off was presented, and a choice response following these signals was unreinforced. The probability of a long response was the same function of a segmented signal and a continuous signal if each segment was considered equivalent to 200 ms. A quantitative fit of a scalar estimation theory suggested that the latencies to initiate temporal integration and to terminate the process are both about 200 ms, and that the same internal accumulation process can be used for counting and timing.

  3. Does Sexual Satisfaction Change With Relationship Duration?

    PubMed

    Schmiedeberg, Claudia; Schröder, Jette

    2016-01-01

    Despite a large body of empirical literature on sexual satisfaction, its development over the course of a relationship is still unclear. Only a small number of studies, most of which have relied on cross-sectional data of convenience samples, have explicitly focused on relationship duration, and empirical evidence is mixed. We analyzed how sexual satisfaction changes over the course of a relationship using three waves of the German Family Panel study (pairfam). We concentrated our analyses on young and middle-aged heterosexual individuals in committed relationships (N = 2,814) and applied fixed effects regression models, which have the advantage of estimations based on changes within individuals over time. We found a positive development of sexual satisfaction in the first year of a relationship, followed by a steady decline. This pattern persisted even when controlling for the frequency of intercourse, although the effects were, in part, mediated by intercourse frequency. We explained the non-linear effect of relationship duration on sexual satisfaction with an initial learning effect regarding partner-specific sexual skills, which is then outweighed by a decline in passion at later stages of a relationship. Moreover, we found significant effects for the control variables of health status, intimacy in couple communication, and conflict style, as expected. In contrast to past research, however, cohabitation and marriage were not found to play a role for sexual satisfaction in our data. Further research is required to deepen the understanding of the reasons why sexual satisfaction changes with relationship duration. PMID:26246315

  4. Evaluation of Long Duration Flight on Venus

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Colozza, Anthony J.

    2006-01-01

    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.

  5. Red blood cell storage duration and trauma.

    PubMed

    Sparrow, Rosemary L

    2015-04-01

    Numerous retrospective clinical studies suggest that transfusion of longer stored red blood cells (RBCs) is associated with an independent risk of poorer outcomes for certain groups of patients, including trauma, intensive care, and cardiac surgery patients. Large multicenter randomized controlled trials are currently underway to address the concern about RBC storage duration. However, none of these randomized controlled trials focus specifically on trauma patients with hemorrhage. Major trauma, particularly due to road accidents, is the leading cause of critical injury in the younger-than-40-year-old age group. Severe bleeding associated with major trauma induces hemodynamic dysregulation that increases the risk of hypoxia, coagulopathy, and potentially multiorgan failure, which can be fatal. In major trauma, a multitude of stress-associated changes occur to the patient's RBCs, including morphological changes that increase cell rigidity and thereby alter blood flow hemodynamics, particularly in the microvascular vessels, and reduce RBC survival. Initial inflammatory responses induce deleterious cellular interactions, including endothelial activation, RBC adhesion, and erythrophagocytosis that are quickly followed by profound immunosuppressive responses. Stored RBCs exhibit similar biophysical characteristics to those of trauma-stressed RBCs. Whether transfusion of RBCs that exhibit storage lesion changes exacerbates the hemodynamic perturbations already active in the trauma patient is not known. This article reviews findings from several recent nonrandomized studies examining RBC storage duration and clinical outcomes in trauma patients. The rationale for further research on RBC storage duration in the trauma setting is provided.

  6. Does Sexual Satisfaction Change With Relationship Duration?

    PubMed

    Schmiedeberg, Claudia; Schröder, Jette

    2016-01-01

    Despite a large body of empirical literature on sexual satisfaction, its development over the course of a relationship is still unclear. Only a small number of studies, most of which have relied on cross-sectional data of convenience samples, have explicitly focused on relationship duration, and empirical evidence is mixed. We analyzed how sexual satisfaction changes over the course of a relationship using three waves of the German Family Panel study (pairfam). We concentrated our analyses on young and middle-aged heterosexual individuals in committed relationships (N = 2,814) and applied fixed effects regression models, which have the advantage of estimations based on changes within individuals over time. We found a positive development of sexual satisfaction in the first year of a relationship, followed by a steady decline. This pattern persisted even when controlling for the frequency of intercourse, although the effects were, in part, mediated by intercourse frequency. We explained the non-linear effect of relationship duration on sexual satisfaction with an initial learning effect regarding partner-specific sexual skills, which is then outweighed by a decline in passion at later stages of a relationship. Moreover, we found significant effects for the control variables of health status, intimacy in couple communication, and conflict style, as expected. In contrast to past research, however, cohabitation and marriage were not found to play a role for sexual satisfaction in our data. Further research is required to deepen the understanding of the reasons why sexual satisfaction changes with relationship duration.

  7. 16 CFR 613.1 - Duration of active duty alerts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Duration of active duty alerts. 613.1 Section 613.1 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT DURATION OF ACTIVE DUTY ALERTS § 613.1 Duration of active duty alerts. The duration of an active duty alert shall...

  8. 16 CFR 613.1 - Duration of active duty alerts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Duration of active duty alerts. 613.1 Section 613.1 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT DURATION OF ACTIVE DUTY ALERTS § 613.1 Duration of active duty alerts. The duration of an active duty alert shall...

  9. 16 CFR 613.1 - Duration of active duty alerts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Duration of active duty alerts. 613.1 Section 613.1 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT DURATION OF ACTIVE DUTY ALERTS § 613.1 Duration of active duty alerts. The duration of an active duty alert shall...

  10. The Prevalence and Diagnostic Validity of Short-Duration Hypomanic Episodes and Major Depressive Episodes.

    PubMed

    Miller, Shefali; Dennehy, Ellen B; Suppes, Trisha

    2016-03-01

    Current diagnostic criteria for a hypomanic episode, as outlined in both the fourth and fifth editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV and DSM-5), require a minimum duration of four consecutive days of symptoms of mood elevation. The 4-day criterion for duration of hypomania has been challenged as arbitrary and lacking empirical support, with many arguing that shorter-duration hypomanic episodes are highly prevalent and that those experiencing these episodes are clinically more similar to patients with bipolar disorder than to those with unipolar major depressive disorder. We review the current evidence regarding the prevalence, diagnostic validity, and longitudinal illness correlates of shorter-duration hypomanic episodes and summarize the arguments for and against broadening the diagnostic criteria for hypomania to include shorter-duration variants. Accumulating findings suggest that patients with major depressive episodes and shorter-duration hypomanic episodes represent a complex clinical phenotype, perhaps best conceptualized as being on the continuum between those with unipolar depressive episodes alone and those with DSM-5-defined bipolar II disorder. Further investigation is warranted, ideally involving large prospective, controlled studies, to elucidate the diagnostic and treatment implications of depression with shorter-duration hypomanic episodes. PMID:26830885

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

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

    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.

  12. Caffeine intake reduces sleep duration in adolescents.

    PubMed

    Lodato, Francesca; Araújo, Joana; Barros, Henrique; Lopes, Carla; Agodi, Antonella; Barchitta, Martina; Ramos, Elisabete

    2013-09-01

    In our study, we hypothesized that higher caffeine intake would be associated with lower sleep duration among 13-year-old adolescents. In addition, we aimed to identify food sources of caffeine intake in this sample. Eligible participants were adolescents who were born in 1990 and attended school in Porto, Portugal, in 2003/2004. Self-administered questionnaires were used, and diet was evaluated using a food frequency questionnaire. From the 2160 eligible participants, only 1522 with valid information regarding their diet were included in this study. In our sample, the median intake of caffeine was 23.1 mg/d, with soft drinks being the major source. Ice tea presented the highest median (25th-75th percentiles) contribution (33.1% [14.0-52.1]), followed by cola (21.1% [6.4-37.6]). Regarding cocoa products, chocolate bars presented a median contribution of 5.1% (1.0-14.0), and snacks containing chocolate had a contribution of 3.0% (0.5-7.2). Coffee and tea presented a negligible contribution. Adolescents who reported less sleep duration and those who spent more time watching TV during the weekend had a significantly higher caffeine intake. Overall, boys had higher intakes of caffeine from soft drinks, and private school attendees, those who had parents with more education, who reported less television viewing time and had lower body mass index presented higher intakes of caffeine from chocolate. Considering sleeping more than 9.5 hours as a reference class, for each increase of 10 mg/d in caffeine intake, we found that the odds ratio of sleeping 8.5 hours or less was 1.12 (95% confidence interval, 1.06-1.19). Our results support the hypothesis that caffeine intake was inversely associated with sleep duration in adolescents.

  13. Long Duration Exposure Facility (LDEF) Archive System

    NASA Technical Reports Server (NTRS)

    Wilson, Brenda K.

    1995-01-01

    The Long Duration Exposure Facility (LDEF) Archive System is designed to provide spacecraft designers and space environment researchers single point access to all available resources from LDEF. These include data, micrographs, photographs, technical reports, papers, hardware and test specimens, as well as technical expertise. Further, the LDEF Archive System is planned such that it could be the foundation for a NASA Space Environments and Effects (SEE) Archive System, with the addition of other spaceflight, laboratory and theoretical space environments and effects data and associated materials. This paper describes the current status and plans of the LDEF Archive System.

  14. Long duration human exposure to microgravity

    NASA Astrophysics Data System (ADS)

    Huntoon, C. L.

    Looking toward the era of long duration manned spaceflight, questions remain regarding human adaptation to the weightless environment. In particular, bone calcium loss, cardiovascular deconditioning, and effects of radiation require further study. NASA has undertaken a series of experiments to increase the knowledge base of human adaptation to spaceflight. To date, results in the area of cardiovascular deconditioning countermeasures are the furthest advanced. The results from the upcoming SLS-1 mission will enhance knowledge in all areas. With continued research, there is every confidence that astronauts will be able to be kept healthy for long periods of time.

  15. Duration test of an annular colloid thruster.

    NASA Technical Reports Server (NTRS)

    Perel, J.; Mahoney, J. F.; Daley, H. L.

    1972-01-01

    An annular colloid thruster was continuously operated for 1023 hours. Performance was stable with no sparking and negligible drain currents observed. An average thrust of 25.1 micropounds and an average specific impulse of 1160 seconds were obtained at an accelerating voltage of 15 k he thruster exhaust beam was continuously neutralized using electrons and electrostatic vectoring was demonstrated periodically. The only clear trend with time was an increase in specific impulse during the last third of the test period. From these results the thruster lifetime was estimated to be over an order of magnitude greater than the test duration.

  16. Long Duration Balloon Charge Controller Stack Integration

    NASA Astrophysics Data System (ADS)

    Clifford, Kyle

    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.

  17. Sound duration as a perceptual cue influencing vocal behavior of male bullfrogs

    NASA Astrophysics Data System (ADS)

    Simmons, Andrea M.

    2002-05-01

    Female frogs of several species use the temporal cue of sound duration to aid in mate choice. Little is known, however, about the sensitivity of male frogs to this cue. Male bullfrogs emit a complex advertisement call to attract females for mating, and to announce territory occupation to other males. In two experiments, the sensitivity of vocalizing male bullfrogs to field playbacks of advertisement calls differing in duration was examined. The number and latency of evoked vocal responses to the stimuli was used as a measure of perception. Males responded with fewer calls, at longer latencies, to stimuli shorter in duration than the standard signal (with a duration at the mean value for the species). Males preferred stimuli longer in duration than the standard signal, responding with more calls at shorter latencies. They did not, however, significantly lengthen their own calls in response to playbacks of long duration signals. This preference for ``supernormal'' stimuli may be an important factor mediating the evolution of communication signals. [Work supported by NIH.

  18. Flood duration and chute cutoff formation in a wandering gravel-bed river

    NASA Astrophysics Data System (ADS)

    Sawyer, A.; Wilcox, A. C.

    2015-12-01

    Chute cutoffs occur when a bypass or "chute" channel incises across a bar or low floodplain area, re-distributing water and sediment. Cutoffs result from a setup and a triggering event, typically during overbank flow, but the combined effect of magnitude and duration on potential erosion in in-channel and overbank areas is still poorly constrained. Here we investigated how overbank flow duration impacts cutoff formation and spatiotemporal shear stress patterns in a wandering gravel-bed river. We applied a two-dimensional hydraulic model to a recently reconstructed reach of the Clark Fork River in western Montana that experienced chute cutoffs during a long-duration flood in 2011. Hydrographs with increasing durations exceeding overbank were simulated; for each magnitude-duration combination, various metrics were quantified for in-channel and overbank areas separately. We confirm the hypothesized importance of floodplain elevation, vegetation presence, chute-channel inlet entrance location, and high overbank shear stress zones at bend apexes on cutoff occurrence. Floodplain width plays an important role in controlling unit discharge such that overbank areas are more competent in a narrower floodplain conveyance corridor. Duration controls cumulative flow exceeding sediment mobility thresholds, having the largest effect in overbank areas. Side channels at the reconstructed study site act like naturally formed incipient chutes. This work describes a complex floodplain system characteristic of wandering gravel-bed rivers with implications for understanding morphodynamic evolution, river restoration, and flow management in regulated rivers.

  19. Long Duration Exposure Facility: A general overview

    NASA Technical Reports Server (NTRS)

    Oneal, Robert L.; Lightner, E. Burton

    1992-01-01

    The Long Duration Exposure Facility (LDEF) is a large, low-cost, reusable, unmanned, free-flying spacecraft which accommodates technology, science, and applications experiments for long-term exposure to the space environment. The LDEF was designed and built by the NASA Langley Research Center (LaRC) for NASA's Office of Aeronautics and Space Technology. Specifically, the LDEF was designed to transport experiments into space via the Space Shuttle, to free fly in Earth orbit for an extended period, and be retrieved on a later Space Shuttle flight allowing experiments to be returned to Earth for postflight analysis in the laboratory. The LDEF with a full complement of experiments was placed in Earth orbit in April 1984 by Challenger and retrieved from orbit in January 1990 by Columbia. A general overview of the LDEF, its mission, systems, experiments, and operations is presented. Excerpts from various NASA documents are extensively used.

  20. Feeding the Astronauts During Long Duration Missions

    NASA Technical Reports Server (NTRS)

    Perchonok, Michele

    2010-01-01

    This slide presentation reviews the issues surrounding feeding astronauts during long duration missions. There is a brief history from the food and food packaging available during Project Mercury through the current food requirements. It shows the packaging and the requirements that have been used. The current food system includes thermostabilized and irradiated foods to reduce the potential of harmful microorganisms. There is an explanation of drinks available, rehydratable foods, and natural forms of food, (i.e., commercially available foods that are packaged in individual serving sizes). There is also discussion of the requirements for future missions, and the research gap for requirements for food that will last 5 years, with packaging and nutrients intact.

  1. Drug stability analyzer for long duration spaceflights

    NASA Astrophysics Data System (ADS)

    Shende, Chetan; Smith, Wayne; Brouillette, Carl; Farquharson, Stuart

    2014-06-01

    Crewmembers of current and future long duration spaceflights require drugs to overcome the deleterious effects of weightlessness, sickness and injuries. Unfortunately, recent studies have shown that some of the drugs currently used may degrade more rapidly in space, losing their potency well before their expiration dates. To complicate matters, the degradation products of some drugs can be toxic. Consequently there is a need for an analyzer that can determine if a drug is safe at the time of use, as well as to monitor and understand space-induced degradation, so that drug types, formulations, and packaging can be improved. Towards this goal we have been investigating the ability of Raman spectroscopy to monitor and quantify drug degradation. Here we present preliminary data by measuring acetaminophen, and its degradation product, p-aminophenol, as pure samples, and during forced degradation reactions.

  2. Long Duration Backlighter Experiments at Omega

    SciTech Connect

    Reighard, A; Glendinning, S; Young, P; Hsing, W; Foord, M; Schneider, M; Lu, K; Dittrich, T; Wallace, R; Sorce, C

    2008-05-01

    We have successfully demonstrated a 7.5 ns-duration pinhole-apertured backlighter at the Omega laser facility. Pinhole-apertured point-projection backlighting for 8 ns will be useful for imaging evolving features in experiments at the National Ignition Facility. The backlighter consisted of a 20 {micro}m diameter pinhole in a 75 {micro}m thick Ta substrate separated from a Zn emitter (9 keV) by a 400 {micro}m thick high-density carbon piece. The carbon prevented the shock from the laser-driven surface from reaching the substrate before 8 ns and helped minimize x-ray ablation of the pinhole substrate. Grid wires in x-ray framing camera images of a gold grid have a source-limited resolution significantly smaller than the pinhole diameter due to the high aspect ratio of the pinhole, but do not become much smaller at late times.

  3. Long duration backlighter experiments at Omega

    SciTech Connect

    Reighard, A. B.; Glendinning, S. G.; Young, P. E.; Hsing, W. W.; Foord, M.; Schneider, M.; Lu, K.; Dittrich, T.; Wallace, R.; Sorce, C.

    2008-10-15

    We have successfully demonstrated a 7.5 ns duration pinhole-apertured backlighter at the Omega laser facility. Pinhole-apertured point-projection backlighting for 8 ns will be useful for imaging evolving features in experiments at the National Ignition Facility. The backlighter consisted of a 20 {mu}m diameter pinhole in a 75 {mu}m thick Ta substrate separated from a Zn emitter (9 keV) by a 400 {mu}m thick high-density carbon piece. The carbon prevented the shock from the laser-driven surface from reaching the substrate before 8 ns and helped minimize x-ray ablation of the pinhole substrate. Grid wires in x-ray framing camera images of a gold grid have a source-limited resolution significantly smaller than the pinhole diameter due to the high aspect ratio of the pinhole, but do not become much smaller at late times.

  4. Period and pulse duration with "strobe" lights

    NASA Astrophysics Data System (ADS)

    Birriel, Jennifer

    2016-01-01

    Strobe lights have traditionally been discussed in The Physics Teacher in the context of stop action strobe photography. During the Halloween season most department and hardware stores sell inexpensive, compact "strobe" lights (although these can be found online year round). These lights generally sell for under 10 and usually employ LED lights. Most such devices have a rotary switch to adjust the rate at which the LED bulbs flash. This rotary switch is not calibrated—i.e., it has no markings to indicate the rate, but in general the greater the rotation of the switch from the off position, the faster the rate of flashing. We show how these simple devices can be used with a light sensor to study both the frequency of flashing and the duration of the light pulse. We briefly discuss if these devices are truly strobe lights.

  5. Short Duration Base Heating Test Improvements

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  6. Architectural considerations for lunar long duration habitat

    NASA Astrophysics Data System (ADS)

    Bahrami, Payam

    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.

  7. 20 CFR 625.7 - Disaster Unemployment Assistance: Duration.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 3 2012-04-01 2012-04-01 false Disaster Unemployment Assistance: Duration... DISASTER UNEMPLOYMENT ASSISTANCE § 625.7 Disaster Unemployment Assistance: Duration. DUA shall be payable... unemployment which begin during a Disaster Assistance Period....

  8. 20 CFR 625.7 - Disaster Unemployment Assistance: Duration.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Disaster Unemployment Assistance: Duration... DISASTER UNEMPLOYMENT ASSISTANCE § 625.7 Disaster Unemployment Assistance: Duration. DUA shall be payable... unemployment which begin during a Disaster Assistance Period....

  9. 20 CFR 625.7 - Disaster Unemployment Assistance: Duration.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Disaster Unemployment Assistance: Duration... DISASTER UNEMPLOYMENT ASSISTANCE § 625.7 Disaster Unemployment Assistance: Duration. DUA shall be payable... unemployment which begin during a Disaster Assistance Period....

  10. 20 CFR 625.7 - Disaster Unemployment Assistance: Duration.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 3 2013-04-01 2013-04-01 false Disaster Unemployment Assistance: Duration... DISASTER UNEMPLOYMENT ASSISTANCE § 625.7 Disaster Unemployment Assistance: Duration. DUA shall be payable... unemployment which begin during a Disaster Assistance Period....

  11. 20 CFR 625.7 - Disaster Unemployment Assistance: Duration.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 3 2014-04-01 2014-04-01 false Disaster Unemployment Assistance: Duration... DISASTER UNEMPLOYMENT ASSISTANCE § 625.7 Disaster Unemployment Assistance: Duration. DUA shall be payable... unemployment which begin during a Disaster Assistance Period....

  12. Sprint performance-duration relationships are set by the fractional duration of external force application.

    PubMed

    Weyand, Peter G; Lin, Jennifer E; Bundle, Matthew W

    2006-03-01

    We hypothesized that the maximum mechanical power outputs that can be maintained during all-out sprint cycling efforts lasting from a few seconds to several minutes can be accurately estimated from a single exponential time constant (k(cycle)) and two measurements on individual cyclists: the peak 3-s power output (P(mech max)) and the maximum mechanical power output that can be supported aerobically (P(aer)). Tests were conducted on seven subjects, four males and three females, on a stationary cycle ergometer at a pedal frequency of 100 rpm. Peak mechanical power output (P(mech max)) was the highest mean power output attained during a 3-s burst; the maximum power output supported aerobically (P(aer)) was determined from rates of oxygen uptake measured during a progressive, discontinuous cycling test to failure. Individual power output-duration relationships were determined from 13 to 16 all-out constant load sprints lasting from 5 to 350 s. In accordance with the above hypothesis, the power outputs measured during all-out sprinting efforts were estimated to within an average of 34 W or 6.6% from P(mech max), P(aer), and a single exponential constant (k(cycle) = 0.026 s(-1)) across a sixfold range of power outputs and a 70-fold range of sprint trial durations (R2 = 0.96 vs. identity, n = 105; range: 180 to 1,136 W). Duration-dependent decrements in sprint cycling power outputs were two times greater than those previously identified for sprint running speed (k(run) = 0.013 s(-1)). When related to the respective times of pedal and ground force application rather than total sprint time, decrements in sprint cycling and running performance followed the same time course (k = 0.054 s(-1)). We conclude that the duration-dependent decrements in sprinting performance are set by the fractional duration of the relevant muscular contractions. PMID:16254125

  13. 20 CFR 725.210 - Duration of augmented benefits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Duration of augmented benefits. 725.210... Entitlement Conditions and Duration of Entitlement: Miner's Dependents (augmented Benefits) § 725.210 Duration of augmented benefits. Augmented benefits payable on behalf of a spouse or divorced spouse, or...

  14. 20 CFR 725.210 - Duration of augmented benefits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Duration of augmented benefits. 725.210... Entitlement Conditions and Duration of Entitlement: Miner's Dependents (augmented Benefits) § 725.210 Duration of augmented benefits. Augmented benefits payable on behalf of a spouse or divorced spouse, or...

  15. 20 CFR 336.2 - Duration of normal unemployment benefits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Duration of normal unemployment benefits. 336... UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal unemployment benefits. (a) 130 compensable day limitation. A qualified employee who has satisfied the...

  16. 20 CFR 336.2 - Duration of normal unemployment benefits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Duration of normal unemployment benefits. 336... UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal unemployment benefits. (a) 130 compensable day limitation. A qualified employee who has satisfied the...

  17. 20 CFR 336.2 - Duration of normal unemployment benefits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Duration of normal unemployment benefits. 336... UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal unemployment benefits. (a) 130 compensable day limitation. A qualified employee who has satisfied the...

  18. 20 CFR 336.2 - Duration of normal unemployment benefits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Duration of normal unemployment benefits. 336... UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal unemployment benefits. (a) 130 compensable day limitation. A qualified employee who has satisfied the...

  19. 20 CFR 336.2 - Duration of normal unemployment benefits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Duration of normal unemployment benefits. 336... UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal unemployment benefits. (a) 130 compensable day limitation. A qualified employee who has satisfied the...

  20. 24 CFR 891.165 - Duration of capital advance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Duration of capital advance. 891... General Program Requirements § 891.165 Duration of capital advance. The duration of the fund reservation for the capital advance is 18 months from the date of issuance with limited exceptions up to 24...

  1. NASA's extended duration orbiter medical program

    NASA Technical Reports Server (NTRS)

    Pool, Sam Lee; Sawin, Charles F.

    1992-01-01

    The physiological issues involved in safely extending Shuttle flights from 10 to 16 days have been viewed by some as academic. After all, they reasoned, humans already have lived and worked in space for periods exceeding even 28 days in the United States Skylab Program and onboard the Russian space stations. The difference in the Shuttle program is in the physical position of the astronauts as they reenter the Earth's atmosphere. Crewmembers in the earlier Apollo, Skylab, and Russian programs were returned to Earth in the supine position. Space Shuttle crewmembers, in contrast, are seated upright during reentry and landing; reexperiencing the Earth's g forces in this position has far more pronounced effects on the crewmember's physiological functions. The goal of the Extended Duration Orbiter (EDO) Medical Project (EDOMP) has been to ensure that crewmembers maintain physiological reserves sufficient to perform entry, landing, and egress safely. Early in the Shuttle Program, it became clear that physiological deconditioning during space flight could produce significant symptoms upon return to Earth. The signs and symptoms observed during the entry, landing, and egress after Shuttle missions have included very high heart rates and low blood pressures upon standing. Dizziness, 'graying out,' and fainting have occurred on ambulation or shortly thereafter. Other symptoms at landing have included headache, light-headedness, nausea and vomitting, leg cramping, inability to stand for several minutes after wheel-stop, and unsteadiness of gait.

  2. Adaptation to ozone: duration of effect

    SciTech Connect

    Horvath, S.M.; Gliner, J.A.; Folinsbee, L.J.

    1981-05-01

    Repeated ozone exposure induces an adaptative response whereby subsequent ozone exposure induces little or no pulmonary function change. The time course of the adaptation and the persistence of this adaptation was determined in 24 subjects. Subjects were studied for 125 min while they exercised intermittently. They were exposed to filtered air for 1 day and then in the next week for 5 consecutive days to 0.5 ppm ozone. After the fifth day, subjects were randomly assigned to return for one more ozone exposure at 1, 2, or 3 wk. The greatest decrement in FEV1 occurred on the second day of exposure. The number of consecutive ozone exposures required to produce adaptation varied from 2 to 5 days. Persistence of adaptation in ozone-sensitive subjects (initial decrease in FEV1 greater than 10%) showed marked individual variability, but the duration of adaptation was shortest for the more sensitive subjects. Adaptation, on the average, lasted for less than 2 wk, being as short as 7 days and as long as 20 days. We concluded that more sensitive subjects required more daily sequential exposures in order to adapt.

  3. Immune changes during short-duration missions

    NASA Technical Reports Server (NTRS)

    Taylor, G. R.

    1993-01-01

    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.

  4. Effects of learning duration on implicit transfer.

    PubMed

    Tanaka, Kanji; Watanabe, Katsumi

    2015-10-01

    Implicit learning and transfer in sequence acquisition play important roles in daily life. Several previous studies have found that even when participants are not aware that a transfer sequence has been transformed from the learning sequence, they are able to perform the transfer sequence faster and more accurately; this suggests implicit transfer of visuomotor sequences. Here, we investigated whether implicit transfer could be modulated by the number of trials completed in a learning session. Participants learned a sequence through trial and error, known as the m × n task (Hikosaka et al. in J Neurophysiol 74:1652-1661, 1995). In the learning session, participants were required to successfully perform the same sequence 4, 12, 16, or 20 times. In the transfer session, participants then learned one of two other sequences: one where the button configuration Vertically Mirrored the learning sequence, or a randomly generated sequence. Our results show that even when participants did not notice the alternation rule (i.e., vertical mirroring), their total working time was less and their total number of errors was lower in the transfer session compared with those who performed a Random sequence, irrespective of the number of trials completed in the learning session. This result suggests that implicit transfer likely occurs even over a shorter learning duration.

  5. Kicking atoms with finite duration pulses

    NASA Astrophysics Data System (ADS)

    Fekete, Julia; Chai, Shijie; Daszuta, Boris; Andersen, Mikkel F.

    2016-05-01

    The atom optics delta-kicked particle is a paradigmatic system for experimental studies of quantum chaos and classical-quantum correspondence. It consists of a cloud of laser cooled atoms exposed to a periodically pulsed standing wave of far off-resonant laser light. A purely quantum phenomena in such systems are quantum resonances which transfers the atoms into a coherent superposition of largely separated momentum states. Using such large momentum transfer ``beamsplitters'' in atom interferometers may have applications in high precision metrology. The growth in momentum separation cannot be maintained indefinitely due to finite laser power. The largest momentum transfer is achieved by violating the usual delta-kick assumption. Therefore we explore the behavior of the atom optics kicked particle with finite pulse duration. We have developed a semi-classical model which shows good agreement with the full quantum description as well as our experiments. Furthermore we have found a simple scaling law that helps to identify optimal parameters for an atom interferometer. We verify this by measurements of the ``Talbot time'' (a measurement of h/m) which together with other well-known constants constitute a measurement of the fine structure constant.

  6. Immune changes during short-duration missions.

    PubMed

    Taylor, G R

    1993-09-01

    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. PMID:8371049

  7. Organizational Determinants of Outpatient Substance Abuse Treatment Duration in Women

    PubMed Central

    Alexander, Jeffrey A.; Lemak, Christy Harris

    2009-01-01

    Longer treatment duration has consistently been related to improved substance use outcomes. This study examined how tailored women's programming and organizational characteristics were related to duration in outpatient substance abuse treatment in women. Data were from two waves of a national outpatient substance abuse treatment unit survey (n=571 in 1999/2000, n=566 in 2005). Analyses were conducted separately for methadone and non-methadone programs. Negative binomial regressions tested associations between organizational determinants, tailored programming, and women's treatment duration. Of the tailored programming services, childcare was significantly related to longer duration in the non-methadone programs, but few other organizational factors were. Tailored programming was not associated to treatment duration in methadone programs, but ownership, affiliation, and accreditation were related to longer duration. Study findings suggest evidence for how external relationships related to resources, treatment constraints, and legitimacy may influence women's treatment duration. Methadone programs may be more vulnerable to external influences. PMID:19038526

  8. Evaluating observational methods to quantify snow duration under diverse forest canopies

    NASA Astrophysics Data System (ADS)

    Dickerson-Lange, Susan E.; Lutz, James A.; Martin, Kael A.; Raleigh, Mark S.; Gersonde, Rolf; Lundquist, Jessica D.

    2015-02-01

    Forests cover almost 40% of the seasonally snow-covered regions in North America. However, operational snow networks are located primarily in forest clearings, and optical remote sensing cannot see through tree canopies to detect forest snowpack. Due to the complex influence of the forest on snowpack duration, ground observations in forests are essential. We therefore consider the effectiveness of different strategies to observe snow-covered area under forests. At our study location in the Pacific Northwest, we simultaneously deployed fiber-optic cable, stand-alone ground temperature sensors, and time-lapse digital cameras in three diverse forest treatments: control second-growth forest, thinned forest, and forest gaps (one tree height in diameter). We derived fractional snow-covered area and snow duration metrics from the colocated instruments to assess optimal spatial resolution and sampling configuration, and snow duration differences between forest treatments. The fiber-optic cable and the cameras indicated that mean snow duration was 8 days longer in the gap plots than in the control plots (p < 0.001). We conducted Monte Carlo experiments for observing mean snow duration in a 40 m forest plot, and found the 95% confidence interval was ±5 days for 10 m spacing between instruments and ±3 days for 6 m spacing. We further tested the representativeness of sampling one plot per treatment group by observing snow duration across replicated forest plots at the same elevation, and at a set of forest plots 250 m higher. Relative relationships between snow duration in the forest treatments are consistent between replicated plots, elevation, and two winters of data.

  9. The influence of stimulus duration on odor perception.

    PubMed

    Frasnelli, Johannes; Wohlgemuth, Christiane; Hummel, Thomas

    2006-10-01

    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 subjects participated. Subjects were investigated on 5 occasions on 5 different days. ERP were recorded to olfactory stimuli of two different concentrations and 3 different durations (100 ms, 200 ms, 300 ms). In two sessions olfactory ERP to PEA were recorded, in another two sessions H2S was applied. During the same sessions, intensity ratings were recorded. In the fifth session, subjects were asked to rate the duration of H2S stimuli and PEA stimuli. Whereas at weak stimulus concentrations no effect of stimulus duration could be observed, there was a clear effect of "duration" in ERP amplitudes following stimuli with higher concentrations: the longer the stimulus duration the larger the ERP amplitudes. No effect was found on ERP latencies. With regard to intensity ratings, strong stimuli and longer lasting stimuli lead to higher ratings. Similarly, ratings of stimulus duration were dependent from stimulus concentration and stimulus duration. Results of the present study showed that similar to trigeminal ERP, information about stimulus duration is encoded in olfactory ERP, mainly in amplitudes.

  10. Duration of patients’ visits to the hospital emergency department

    PubMed Central

    2012-01-01

    Background Length of stay is an important indicator of quality of care in Emergency Departments (ED). This study explores the duration of patients’ visits to the ED for which they are treated and released (T&R). Methods Retrospective data analysis and multivariate regression analysis were conducted to investigate the duration of T&R ED visits. Duration for each visit was computed by taking the difference between admission and discharge times. The Healthcare Cost and Utilization Project (HCUP) State Emergency Department Databases (SEDD) for 2008 were used in the analysis. Results The mean duration of T&R ED visit was 195.7 minutes. The average duration of ED visits increased from 8 a.m. until noon, then decreased until midnight at which we observed an approximately 70-minute spike in average duration. We found a substantial difference in mean duration of ED visits (over 90 minutes) between Mondays and other weekdays during the transition time from the evening of the day before to the early morning hours. Black / African American patients had a 21.4-minute longer mean duration of visits compared to white patients. The mean duration of visits at teaching hospitals was substantially longer than at non-teaching hospitals (243.8 versus 175.6 minutes). Hospitals with large bed size were associated with longer duration of visits (222.2 minutes) when compared to hospitals with small bed size (172.4 minutes) or those with medium bed size (166.5 minutes). The risk-adjusted results show that mean duration of visits on Mondays are longer by about 4 and 9 percents when compared to mean duration of visits on non-Monday workdays and weekends, respectively. Conclusions The duration of T&R ED visits varied significantly by admission hour, day of the week, patient volume, patient characteristics, hospital characteristics and area characteristics. PMID:23126473

  11. How Hearing Impairment Affects Sentence Comprehension: Using Eye Fixations to Investigate the Duration of Speech Processing

    PubMed Central

    Kollmeier, Birger; Brand, Thomas

    2015-01-01

    The main objective of this study was to investigate the extent to which hearing impairment influences the duration of sentence processing. An eye-tracking paradigm is introduced that provides an online measure of how hearing impairment prolongs processing of linguistically complex sentences; this measure uses eye fixations recorded while the participant listens to a sentence. Eye fixations toward a target picture (which matches the aurally presented sentence) were measured in the presence of a competitor picture. Based on the recorded eye fixations, the single target detection amplitude, which reflects the tendency of the participant to fixate the target picture, was used as a metric to estimate the duration of sentence processing. The single target detection amplitude was calculated for sentence structures with different levels of linguistic complexity and for different listening conditions: in quiet and in two different noise conditions. Participants with hearing impairment spent more time processing sentences, even at high levels of speech intelligibility. In addition, the relationship between the proposed online measure and listener-specific factors, such as hearing aid use and cognitive abilities, was investigated. Longer processing durations were measured for participants with hearing impairment who were not accustomed to using a hearing aid. Moreover, significant correlations were found between sentence processing duration and individual cognitive abilities (such as working memory capacity or susceptibility to interference). These findings are discussed with respect to audiological applications. PMID:25910503

  12. Personal growth following long-duration spaceflight

    NASA Astrophysics Data System (ADS)

    Suedfeld, Peter; Brcic, Jelena; Johnson, Phyllis J.; Gushin, Vadim

    2012-10-01

    that cosmonauts do experience various aspects of positive personal growth following their space flights. As long-duration missions are (and will remain) the norm, it is important for the space agencies and the voyagers themselves to develop a better understanding and possible enhancement of this phenomenon.

  13. Enhancing Team Performance for Long-Duration Space Missions

    NASA Technical Reports Server (NTRS)

    Orasanu, Judith M.

    2009-01-01

    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.

  14. Factors that Influence Weekday Sleep Duration in European Children

    PubMed Central

    Hense, Sabrina; Barba, Gianvincenzo; Pohlabeln, Hermann; De Henauw, Stefaan; Marild, Staffan; Molnar, Dénes; Moreno, Luis A.; Hadjigeorgiou, Charalampos; Veidebaum, Toomas; Ahrens, Wolfgang

    2011-01-01

    Study Objectives: To compare nocturnal sleep duration in children from 8 European countries and identify its determinants. Design: Cross-sectional. Setting: Primary schools and preschools participating in the IDEFICS study. Participants: 8,542 children aged 2 to 9 years from 8 European countries with complete information on nocturnal sleep duration. Interventions: Not applicable. Measurements: Nocturnal sleep duration was assessed by means of a computer based parental 24-h recall. Data on personal, social, environmental, and behavioral factors were collected by means of standardized parental questionnaire. Physical activity was surveyed with accelerometers. Results: Nocturnal sleep duration in the participating countries ranged from 9.5 h (SD 0.8) in Estonia to 11.2 h (SD 0.7) in Belgium and differed significantly between countries (P < 0.001) in univariate as well as in multivariate analyses, with children from northern countries sleeping the longest. Sleep duration decreased by about 6 min with each year of age over all countries. No effect of season, daylight duration, overweight, parental education level, or lifestyle factors could be seen. Conclusion: Sleep duration differs significantly between countries. Our findings allow for the conclusion that regional affiliation, including culture and environmental characteristics, seems to overlay individual determinants of sleep duration. Citation: Hense S; Barba G; Pohlabeln H; De Henauw S; Marild S; Molnar D; Moreno LA; Hadjigeorgiou C; Veidebaum T; Ahrens W. Factors that influence weekday sleep duration in European children. SLEEP 2011;34(5):633-639. PMID:21532957

  15. Hazard based models for freeway traffic incident duration.

    PubMed

    Tavassoli Hojati, Ahmad; Ferreira, Luis; Washington, Simon; Charles, Phil

    2013-03-01

    Assessing and prioritising cost-effective strategies to mitigate the impacts of traffic incidents and accidents on non-recurrent congestion on major roads represents a significant challenge for road network managers. This research examines the influence of numerous factors associated with incidents of various types on their duration. It presents a comprehensive traffic incident data mining and analysis by developing an incident duration model based on twelve months of incident data obtained from the Australian freeway network. Parametric accelerated failure time (AFT) survival models of incident duration were developed, including log-logistic, lognormal, and Weibul-considering both fixed and random parameters, as well as a Weibull model with gamma heterogeneity. The Weibull AFT models with random parameters were appropriate for modelling incident duration arising from crashes and hazards. A Weibull model with gamma heterogeneity was most suitable for modelling incident duration of stationary vehicles. Significant variables affecting incident duration include characteristics of the incidents (severity, type, towing requirements, etc.), and location, time of day, and traffic characteristics of the incident. Moreover, the findings reveal no significant effects of infrastructure and weather on incident duration. A significant and unique contribution of this paper is that the durations of each type of incident are uniquely different and respond to different factors. The results of this study are useful for traffic incident management agencies to implement strategies to reduce incident duration, leading to reduced congestion, secondary incidents, and the associated human and economic losses.

  16. Hazard based models for freeway traffic incident duration.

    PubMed

    Tavassoli Hojati, Ahmad; Ferreira, Luis; Washington, Simon; Charles, Phil

    2013-03-01

    Assessing and prioritising cost-effective strategies to mitigate the impacts of traffic incidents and accidents on non-recurrent congestion on major roads represents a significant challenge for road network managers. This research examines the influence of numerous factors associated with incidents of various types on their duration. It presents a comprehensive traffic incident data mining and analysis by developing an incident duration model based on twelve months of incident data obtained from the Australian freeway network. Parametric accelerated failure time (AFT) survival models of incident duration were developed, including log-logistic, lognormal, and Weibul-considering both fixed and random parameters, as well as a Weibull model with gamma heterogeneity. The Weibull AFT models with random parameters were appropriate for modelling incident duration arising from crashes and hazards. A Weibull model with gamma heterogeneity was most suitable for modelling incident duration of stationary vehicles. Significant variables affecting incident duration include characteristics of the incidents (severity, type, towing requirements, etc.), and location, time of day, and traffic characteristics of the incident. Moreover, the findings reveal no significant effects of infrastructure and weather on incident duration. A significant and unique contribution of this paper is that the durations of each type of incident are uniquely different and respond to different factors. The results of this study are useful for traffic incident management agencies to implement strategies to reduce incident duration, leading to reduced congestion, secondary incidents, and the associated human and economic losses. PMID:23333698

  17. 14 CFR § 1203.407 - Duration of classification.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... event for declassification based on the duration of the national security sensitivity of the information... original classification authority otherwise determines that the sensitivity of the information...

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

    PubMed

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

    2014-08-01

    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

  19. Sleep Duration and Depressive Symptoms: A Gene-Environment Interaction

    PubMed Central

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

    2014-01-01

    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

  20. The Impact of Attention on Judgments of Frequency and Duration

    PubMed Central

    Winkler, Isabell; Glauer, Madlen; Betsch, Tilmann; Sedlmeier, Peter

    2015-01-01

    Previous studies that examined human judgments of frequency and duration found an asymmetrical relationship: While frequency judgments were quite accurate and independent of stimulus duration, duration judgments were highly dependent upon stimulus frequency. A potential explanation for these findings is that the asymmetry is moderated by the amount of attention directed to the stimuli. In the current experiment, participants' attention was manipulated in two ways: (a) intrinsically, by varying the type and arousal potential of the stimuli (names, low-arousal and high-arousal pictures), and (b) extrinsically, by varying the physical effort participants expended during the stimulus presentation (by lifting a dumbbell vs. relaxing the arm). Participants processed stimuli with varying presentation frequencies and durations and were subsequently asked to estimate the frequency and duration of each stimulus. Sensitivity to duration increased for pictures in general, especially when processed under physical effort. A large effect of stimulus frequency on duration judgments was obtained for all experimental conditions, but a similar large effect of presentation duration on frequency judgments emerged only in the conditions that could be expected to draw high amounts of attention to the stimuli: when pictures were judged under high physical effort. Almost no difference in the mutual impact of frequency and duration was obtained for low-arousal or high-arousal pictures. The mechanisms underlying the simultaneous processing of frequency and duration are discussed with respect to existing models derived from animal research. Options for the extension of such models to human processing of frequency and duration are suggested. PMID:26000712

  1. Simultaneous optimization of power and duration of radio-frequency pulse in PARACEST MRI.

    PubMed

    Rezaeian, Mohammad-Reza; Hossein-Zadeh, Gholam-Ali; Soltanian-Zadeh, Hamid

    2016-07-01

    Chemical exchange saturation transfer (CEST) MRI is increasingly used to probe mobile proteins and microenvironment properties, and shows great promise for tumor and stroke diagnosis. The CEST effect is complex and depends not only on the CEST agent concentration, exchange rates, the characteristic of the magnetization transfer (MT), and the relaxation properties of the tissue, but also varies with the experimental conditions such as radio-frequency (RF) pulse power and duration. The RF pulse is one of the most important factors that promote the CEST effect for biological properties such as pH, temperature and protein content, especially for contrast agents with intermediate to fast exchange rates. The CEST effect is susceptible to the RF duration and power. The present study aims at determining the optimal power and the corresponding optimal duration (that maximize the CEST effect) using an off-resonance scheme through a new definition of the CEST effect. This definition is formulated by solving the Bloch-McConnell equation through the R1ρ method (based on the eigenspace solution) for both of the MT and CEST effects as well as their interactions. The proposed formulations of the optimal RF pulse power and duration are the first formulations in which the MT effect is considered. The extracted optimal RF pulse duration and power are compared with those of the MTR asymmetry model in two- and three-pool systems, using synthetic data that are similar to the muscle tissue. To validate them further, the formulations are compared with the empirical formulation of the CEST effect and other findings of the previous researches. By extending our formulations, the optimal power and the corresponding optimal duration (in the biological systems with many chemical exchange sites) can be determined. PMID:26956610

  2. Evaluating Observational Methods to Quantify Snow Duration under Diverse Forest Canopies

    NASA Astrophysics Data System (ADS)

    Dickerson-Lange, S. E.; Lutz, J. A.; Martin, K.; Raleigh, M. S.; Gersonde, R.; Lundquist, J. D.

    2014-12-01

    Forests cover over 40% of the seasonally snow-covered regions in North America. However, operational snow networks are located primarily in forest clearings, and optical remote sensing cannot see through tree canopies to detect forest snowpack. Due to the complex influence of the forest on snowpack duration, ground observations in forests are essential. We therefore consider the effectiveness of different strategies to observe snow covered area under forests. At our study location in the Pacific Northwest, we simultaneously deployed fiber-optic cable, stand-alone ground temperature sensors, and time-lapse digital cameras in three different forest treatments: control second-growth forest, thinned forest, and forest gaps (one tree height in diameter). We derived fractional snow covered area and snow duration metrics from the co-located instruments to assess optimal spatial resolution and sampling configuration. The fiber-optic cable and the camera detected a significant difference of 8 days in mean snow duration between the gap and control plots. Monte Carlo experiments based on our results suggest that 10 m spacing of self-recording ground temperature sensors across a 40 m forest plot will capture mean snow duration to ± 5 days whereas 6 m spacing reduces the 95% confidence interval to ± 3 days. We further tested the representativeness of sampling one plot per treatment group by observing snow duration across replicated forest plots at the same elevation, and at a set of forest plots 250 m higher. Relative relationships between snow duration in the forest treatments are consistent between replicated plots, elevation, and two winters of data.

  3. 10 CFR 52.33 - Duration of renewal.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Duration of renewal. 52.33 Section 52.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Early Site Permits § 52.33 Duration of renewal. Each renewal of an early site permit may be for not less than 10,...

  4. 10 CFR 52.26 - Duration of permit.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Duration of permit. 52.26 Section 52.26 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Early Site Permits § 52.26 Duration of permit. (a) Except as provided in paragraph (b) of this section, an early...

  5. 49 CFR 525.9 - Duration of exemption.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Duration of exemption. 525.9 Section 525.9 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EXEMPTIONS FROM AVERAGE FUEL ECONOMY STANDARDS § 525.9 Duration...

  6. 49 CFR 525.9 - Duration of exemption.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Duration of exemption. 525.9 Section 525.9 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EXEMPTIONS FROM AVERAGE FUEL ECONOMY STANDARDS § 525.9 Duration...

  7. Duration of Sleep and ADHD Tendency among Adolescents in China

    ERIC Educational Resources Information Center

    Lam, Lawrence T.; Yang, L.

    2008-01-01

    Objective: This study investigates the association between duration of sleep and ADHD tendency among adolescents. Method: This population-based health survey uses a two-stage random cluster sampling design. Participants ages 13 to 17 are recruited from the total population of adolescents attending high school in one city of China. Duration of…

  8. 10 CFR 451.6 - Duration of incentive payments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Duration of incentive payments. 451.6 Section 451.6 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of incentive... part with respect to a qualified renewable energy facility for 10 consecutive fiscal years. Such...

  9. 10 CFR 451.6 - Duration of incentive payments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Duration of incentive payments. 451.6 Section 451.6 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of incentive... part with respect to a qualified renewable energy facility for 10 consecutive fiscal years. Such...

  10. 10 CFR 451.6 - Duration of incentive payments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Duration of incentive payments. 451.6 Section 451.6 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of incentive... part with respect to a qualified renewable energy facility for 10 consecutive fiscal years. Such...

  11. 10 CFR 451.6 - Duration of incentive payments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Duration of incentive payments. 451.6 Section 451.6 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of incentive... part with respect to a qualified renewable energy facility for 10 consecutive fiscal years. Such...

  12. 10 CFR 451.6 - Duration of incentive payments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Duration of incentive payments. 451.6 Section 451.6 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.6 Duration of incentive... part with respect to a qualified renewable energy facility for 10 consecutive fiscal years. Such...

  13. 10 CFR 52.33 - Duration of renewal.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Duration of renewal. 52.33 Section 52.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Early Site Permits § 52.33 Duration of renewal. Each renewal of an early site permit may be for not less than 10,...

  14. 10 CFR 52.33 - Duration of renewal.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Duration of renewal. 52.33 Section 52.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Early Site Permits § 52.33 Duration of renewal. Each renewal of an early site permit may be for not less than 10,...

  15. 10 CFR 52.61 - Duration of renewal.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Duration of renewal. 52.61 Section 52.61 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Standard Design Certifications § 52.61 Duration of renewal. Each renewal of certification for a standard...

  16. 10 CFR 52.61 - Duration of renewal.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Duration of renewal. 52.61 Section 52.61 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Standard Design Certifications § 52.61 Duration of renewal. Each renewal of certification for a standard...

  17. 10 CFR 52.61 - Duration of renewal.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Duration of renewal. 52.61 Section 52.61 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Standard Design Certifications § 52.61 Duration of renewal. Each renewal of certification for a standard...

  18. 10 CFR 52.61 - Duration of renewal.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Duration of renewal. 52.61 Section 52.61 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Standard Design Certifications § 52.61 Duration of renewal. Each renewal of certification for a standard...

  19. 10 CFR 52.61 - Duration of renewal.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Duration of renewal. 52.61 Section 52.61 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Standard Design Certifications § 52.61 Duration of renewal. Each renewal of certification for a standard...

  20. 10 CFR 52.33 - Duration of renewal.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Duration of renewal. 52.33 Section 52.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Early Site Permits § 52.33 Duration of renewal. Each renewal of an early site permit may be for not less than 10,...

  1. 10 CFR 52.33 - Duration of renewal.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Duration of renewal. 52.33 Section 52.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Early Site Permits § 52.33 Duration of renewal. Each renewal of an early site permit may be for not less than 10,...

  2. 10 CFR 72.42 - Duration of license; renewal.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Duration of license; renewal. 72.42 Section 72.42 Energy... Conditions of License § 72.42 Duration of license; renewal. (a) Each license issued under this part must be... the requirements of this rule. Application for ISFSI license renewals must include the following:...

  3. 30 CFR 57.6406 - Duration of current flow.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Duration of current flow. 57.6406 Section 57... Electric Blasting-Surface and Underground § 57.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current...

  4. 30 CFR 56.6406 - Duration of current flow.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Duration of current flow. 56.6406 Section 56... Blasting § 56.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current flow shall be limited to a maximum of...

  5. 30 CFR 57.6406 - Duration of current flow.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Duration of current flow. 57.6406 Section 57... Electric Blasting-Surface and Underground § 57.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current...

  6. 30 CFR 57.6406 - Duration of current flow.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Duration of current flow. 57.6406 Section 57... Electric Blasting-Surface and Underground § 57.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current...

  7. 30 CFR 57.6406 - Duration of current flow.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Duration of current flow. 57.6406 Section 57... Electric Blasting-Surface and Underground § 57.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current...

  8. 30 CFR 56.6406 - Duration of current flow.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Duration of current flow. 56.6406 Section 56... Blasting § 56.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current flow shall be limited to a maximum of...

  9. 30 CFR 57.6406 - Duration of current flow.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Duration of current flow. 57.6406 Section 57... Electric Blasting-Surface and Underground § 57.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current...

  10. 30 CFR 56.6406 - Duration of current flow.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Duration of current flow. 56.6406 Section 56... Blasting § 56.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current flow shall be limited to a maximum of...

  11. 30 CFR 56.6406 - Duration of current flow.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Duration of current flow. 56.6406 Section 56... Blasting § 56.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current flow shall be limited to a maximum of...

  12. 30 CFR 56.6406 - Duration of current flow.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Duration of current flow. 56.6406 Section 56... Blasting § 56.6406 Duration of current flow. If any part of a blast is connected in parallel and is to be initiated from powerlines or lighting circuits, the time of current flow shall be limited to a maximum of...

  13. 38 CFR 60.7 - Duration of temporary lodging.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2012-07-01 2012-07-01 false Duration of temporary lodging. 60.7 Section 60.7 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) FISHER HOUSES AND OTHER TEMPORARY LODGING § 60.7 Duration of temporary lodging. Temporary...

  14. 24 CFR 203.267 - Duration of periodic MIP.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Duration of periodic MIP. 203.267 Section 203.267 Housing and Urban Development Regulations Relating to Housing and Urban Development... Payment § 203.267 Duration of periodic MIP. The mortgagee shall pay the MIP to the Commissioner until...

  15. 24 CFR 203.267 - Duration of periodic MIP.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Duration of periodic MIP. 203.267 Section 203.267 Housing and Urban Development Regulations Relating to Housing and Urban Development... Payment § 203.267 Duration of periodic MIP. The mortgagee shall pay the MIP to the Commissioner until...

  16. 24 CFR 203.267 - Duration of periodic MIP.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Duration of periodic MIP. 203.267 Section 203.267 Housing and Urban Development Regulations Relating to Housing and Urban Development... Payment § 203.267 Duration of periodic MIP. The mortgagee shall pay the MIP to the Commissioner until...

  17. 24 CFR 203.267 - Duration of periodic MIP.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Duration of periodic MIP. 203.267 Section 203.267 Housing and Urban Development Regulations Relating to Housing and Urban Development... Payment § 203.267 Duration of periodic MIP. The mortgagee shall pay the MIP to the Commissioner until...

  18. 24 CFR 203.267 - Duration of periodic MIP.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Duration of periodic MIP. 203.267 Section 203.267 Housing and Urban Development Regulations Relating to Housing and Urban Development... Payment § 203.267 Duration of periodic MIP. The mortgagee shall pay the MIP to the Commissioner until...

  19. The Effect of Student Aid on the Duration of Study

    ERIC Educational Resources Information Center

    Glocker, Daniela

    2011-01-01

    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…

  20. 38 CFR 21.73 - Duration of employment assistance programs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... assistance programs. 21.73 Section 21.73 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Duration of Rehabilitation Programs § 21.73 Duration of employment...

  1. 25 CFR 211.27 - Duration of leases.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF TRIBAL LANDS FOR MINERAL... duration shall be measured from the date of approval by the Secretary. (b) An oil and gas or geothermal... duration without actual production of oil, gas, or geothermal resources. Provided, that this extension...

  2. 25 CFR 211.27 - Duration of leases.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF TRIBAL LANDS FOR MINERAL... duration shall be measured from the date of approval by the Secretary. (b) An oil and gas or geothermal... duration without actual production of oil, gas, or geothermal resources. Provided, that this extension...

  3. 25 CFR 211.27 - Duration of leases.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF TRIBAL LANDS FOR MINERAL... duration shall be measured from the date of approval by the Secretary. (b) An oil and gas or geothermal... duration without actual production of oil, gas, or geothermal resources. Provided, that this extension...

  4. 25 CFR 211.27 - Duration of leases.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF TRIBAL LANDS FOR MINERAL... duration shall be measured from the date of approval by the Secretary. (b) An oil and gas or geothermal... duration without actual production of oil, gas, or geothermal resources. Provided, that this extension...

  5. 7 CFR 922.67 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 922.67 Section 922.67... COUNTIES IN WASHINGTON Order Regulating Handling Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart...

  6. 7 CFR 922.67 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 922.67 Section 922.67... COUNTIES IN WASHINGTON Order Regulating Handling Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart...

  7. 7 CFR 966.87 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 966.87 Section 966.87... Regulating Handling Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  8. 7 CFR 948.87 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 948.87 Section 948.87... Order Regulating Handling Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of this subpart shall cease upon...

  9. 7 CFR 925.66 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 925.66 Section 925.66... OF SOUTHEASTERN CALIFORNIA Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  10. 7 CFR 993.87 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 993.87 Section 993.87... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  11. 7 CFR 982.84 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 982.84 Section 982.84... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  12. 7 CFR 932.71 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 932.71 Section 932.71... Regulating Handling Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  13. 7 CFR 947.83 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities...

  14. 7 CFR 958.83 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  15. 7 CFR 946.73 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 946.73 Section 946.73... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  16. 7 CFR 947.83 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities...

  17. 7 CFR 947.83 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities...

  18. 7 CFR 915.67 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 915.67 Section 915.67... Order Regulating Handling Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  19. 7 CFR 993.87 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 993.87 Section 993.87... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  20. 7 CFR 932.71 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 932.71 Section 932.71... Regulating Handling Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  1. 7 CFR 945.86 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  2. 7 CFR 985.69 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing....69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  3. 7 CFR 948.87 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 948.87 Section 948.87... Order Regulating Handling Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of this subpart shall cease upon...

  4. 7 CFR 989.88 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 989.88 Section 989.88... GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this amended...

  5. 7 CFR 959.87 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 959.87 Section 959.87... Regulating Handling Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  6. 7 CFR 917.65 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 917.65 Section 917.65... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the provisions of this subpart shall cease upon...

  7. 7 CFR 916.67 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 916.67 Section 916.67... Order Regulating Handling Miscellaneous Provisions § 916.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  8. 7 CFR 983.85 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 983.85 Section 983.85..., ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  9. 7 CFR 983.85 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 983.85 Section 983.85..., ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  10. 7 CFR 982.84 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 982.84 Section 982.84... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  11. 7 CFR 915.67 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 915.67 Section 915.67... Order Regulating Handling Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  12. 7 CFR 985.69 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing....69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  13. 7 CFR 947.83 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities...

  14. 7 CFR 917.65 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 917.65 Section 917.65... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the provisions of this subpart shall cease upon...

  15. 7 CFR 930.86 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 930.86 Section 930.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Miscellaneous Provisions § 930.86 Duration of immunities. The benefits, privileges, and...

  16. 7 CFR 946.73 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 946.73 Section 946.73... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  17. 7 CFR 948.87 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 948.87 Section 948.87... Order Regulating Handling Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of this subpart shall cease upon...

  18. 7 CFR 945.86 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  19. 7 CFR 925.66 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 925.66 Section 925.66... OF SOUTHEASTERN CALIFORNIA Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  20. 7 CFR 922.67 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 922.67 Section 922.67... COUNTIES IN WASHINGTON Order Regulating Handling Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart...

  1. 7 CFR 993.87 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 993.87 Section 993.87... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  2. 7 CFR 983.85 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 983.85 Section 983.85..., ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  3. 7 CFR 959.87 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 959.87 Section 959.87... Regulating Handling Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  4. 7 CFR 946.73 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 946.73 Section 946.73... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  5. 7 CFR 966.87 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 966.87 Section 966.87... Regulating Handling Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  6. 7 CFR 930.86 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 930.86 Section 930.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Miscellaneous Provisions § 930.86 Duration of immunities. The benefits, privileges, and...

  7. 7 CFR 932.71 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 932.71 Section 932.71... Regulating Handling Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  8. 7 CFR 925.66 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 925.66 Section 925.66... OF SOUTHEASTERN CALIFORNIA Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  9. 7 CFR 945.86 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  10. 7 CFR 966.87 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 966.87 Section 966.87... Regulating Handling Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  11. 7 CFR 915.67 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 915.67 Section 915.67... Order Regulating Handling Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  12. 7 CFR 948.87 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 948.87 Section 948.87... Order Regulating Handling Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of this subpart shall cease upon...

  13. 7 CFR 989.88 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 989.88 Section 989.88... GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this amended...

  14. 7 CFR 915.67 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 915.67 Section 915.67... Order Regulating Handling Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  15. 7 CFR 966.87 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 966.87 Section 966.87... Regulating Handling Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  16. 7 CFR 982.84 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 982.84 Section 982.84... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  17. 7 CFR 959.87 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 959.87 Section 959.87... Regulating Handling Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  18. 7 CFR 958.83 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  19. 7 CFR 953.78 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 953.78 Section 953.78... SOUTHEASTERN STATES Order Regulating Handling Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease...

  20. 7 CFR 985.69 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING....69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  1. 7 CFR 917.65 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 917.65 Section 917.65... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the provisions of this subpart shall cease upon...

  2. 7 CFR 981.88 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 981.88 Section 981.88... Regulating Handling Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon its termination except...

  3. 7 CFR 982.84 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 982.84 Section 982.84... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  4. 7 CFR 917.65 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 917.65 Section 917.65... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the provisions of this subpart shall cease upon...

  5. 7 CFR 946.73 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 946.73 Section 946.73... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  6. 7 CFR 985.69 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing....69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  7. 7 CFR 948.87 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 948.87 Section 948.87... Order Regulating Handling Miscellaneous Provisions § 948.87 Duration of immunities. The benefits, privileges and immunities conferred upon any person by virtue of this subpart shall cease upon...

  8. 7 CFR 985.69 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 985.69 Section 985.69 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING....69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  9. 7 CFR 953.78 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 953.78 Section 953.78... SOUTHEASTERN STATES Order Regulating Handling Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease...

  10. 7 CFR 925.66 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 925.66 Section 925.66... OF SOUTHEASTERN CALIFORNIA Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  11. 7 CFR 993.87 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 993.87 Section 993.87... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  12. 7 CFR 983.85 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 983.85 Section 983.85..., ARIZONA, AND NEW MEXICO Miscellaneous Provisions § 983.85 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  13. 7 CFR 945.86 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  14. 7 CFR 982.84 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 982.84 Section 982.84... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 982.84 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  15. 7 CFR 946.73 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 946.73 Section 946.73... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 946.73 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  16. 7 CFR 966.87 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 966.87 Section 966.87... Regulating Handling Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  17. 7 CFR 915.67 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 915.67 Section 915.67... Order Regulating Handling Miscellaneous Provisions § 915.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  18. 7 CFR 916.67 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 916.67 Section 916.67... Order Regulating Handling Miscellaneous Provisions § 916.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  19. 7 CFR 932.71 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 932.71 Section 932.71... Regulating Handling Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  20. 7 CFR 981.88 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 981.88 Section 981.88... Regulating Handling Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon its termination except...

  1. 7 CFR 927.72 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 927.72 Section 927.72... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart shall cease upon termination hereof,...

  2. 7 CFR 927.72 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 927.72 Section 927.72... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart shall cease upon termination hereof,...

  3. 7 CFR 981.88 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 981.88 Section 981.88... Regulating Handling Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon its termination except...

  4. 7 CFR 930.86 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 930.86 Section 930.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Handling Miscellaneous Provisions § 930.86 Duration of immunities. The benefits, privileges, and...

  5. 7 CFR 959.87 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 959.87 Section 959.87... Regulating Handling Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  6. 7 CFR 958.83 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  7. 7 CFR 924.67 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 924.67 Section 924.67 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 924.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  8. 7 CFR 989.88 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 989.88 Section 989.88... GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this amended...

  9. 7 CFR 917.65 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 917.65 Section 917.65... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 917.65 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of the provisions of this subpart shall cease upon...

  10. 7 CFR 927.72 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 927.72 Section 927.72... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart shall cease upon termination hereof,...

  11. 7 CFR 958.83 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  12. 7 CFR 932.71 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 932.71 Section 932.71... Regulating Handling Miscellaneous Provisions § 932.71 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  13. 7 CFR 930.86 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 930.86 Section 930.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Handling Miscellaneous Provisions § 930.86 Duration of immunities. The benefits, privileges, and...

  14. 7 CFR 958.83 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 958.83 Section 958.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 958.83 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  15. 7 CFR 959.87 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 959.87 Section 959.87... Regulating Handling Miscellaneous Provisions § 959.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination of...

  16. 7 CFR 947.83 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 947.83 Section 947.83 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Miscellaneous Provisions § 947.83 Duration of immunities. The benefits, privileges, and immunities...

  17. 7 CFR 922.67 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 922.67 Section 922.67... COUNTIES IN WASHINGTON Order Regulating Handling Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart...

  18. 7 CFR 993.87 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 993.87 Section 993.87... CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 993.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon...

  19. 7 CFR 924.67 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 924.67 Section 924.67 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 924.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  20. 7 CFR 953.78 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Duration of immunities. 953.78 Section 953.78... SOUTHEASTERN STATES Order Regulating Handling Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease...

  1. 7 CFR 953.78 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 953.78 Section 953.78... SOUTHEASTERN STATES Order Regulating Handling Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease...

  2. 7 CFR 989.88 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 989.88 Section 989.88... GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this amended...

  3. 7 CFR 927.72 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 927.72 Section 927.72... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart shall cease upon termination hereof,...

  4. 7 CFR 981.88 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 981.88 Section 981.88... Regulating Handling Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon its termination except...

  5. 7 CFR 953.78 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 953.78 Section 953.78... SOUTHEASTERN STATES Order Regulating Handling Miscellaneous Provisions § 953.78 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease...

  6. 7 CFR 945.86 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 945.86 Section 945.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 945.86 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  7. 7 CFR 981.88 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 981.88 Section 981.88... Regulating Handling Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon its termination except...

  8. 7 CFR 922.67 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 922.67 Section 922.67... COUNTIES IN WASHINGTON Order Regulating Handling Miscellaneous Provisions § 922.67 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart...

  9. 7 CFR 925.66 - Duration of immunities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Duration of immunities. 925.66 Section 925.66... OF SOUTHEASTERN CALIFORNIA Miscellaneous Provisions § 925.66 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this part shall cease upon its...

  10. 7 CFR 930.86 - Duration of immunities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Duration of immunities. 930.86 Section 930.86 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Handling Miscellaneous Provisions § 930.86 Duration of immunities. The benefits, privileges, and...

  11. 7 CFR 989.88 - Duration of immunities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Duration of immunities. 989.88 Section 989.88... GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 989.88 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this amended...

  12. 7 CFR 927.72 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Duration of immunities. 927.72 Section 927.72... WASHINGTON Order Regulating Handling Miscellaneous Provisions § 927.72 Duration of immunities. The benefits, privileges, and immunities conferred by virtue of this subpart shall cease upon termination hereof,...

  13. 25 CFR 212.27 - Duration of leases.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Duration of leases. 212.27 Section 212.27 Indians BUREAU... MINERAL DEVELOPMENT How To Acquire Leases § 212.27 Duration of leases. The provisions of § 211.27 of this subchapter are applicable to leases under this part....

  14. 14 CFR 63.15 - Duration of certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Duration of certificates. 63.15 Section 63...) AIRMEN CERTIFICATION: FLIGHT CREWMEMBERS OTHER THAN PILOTS General § 63.15 Duration of certificates. (a... month in which the certificate was issued or renewed. However, the holder may exercise the privileges...

  15. 14 CFR 65.15 - Duration of certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Duration of certificates. 65.15 Section 65...) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS General § 65.15 Duration of certificates. (a... certificates issued under § 65.13, the holder of a paper certificate issued under this part may not...

  16. 40 CFR 85.2303 - Duration of model year.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Duration of model year. 85.2303... (CONTINUED) CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Determination of Model Year for Motor Vehicles and... Duration of model year. A specific model year must always include January 1 of the calendar year for...

  17. 40 CFR 85.2303 - Duration of model year.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Duration of model year. 85.2303... (CONTINUED) CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Determination of Model Year for Motor Vehicles and... Duration of model year. A specific model year must always include January 1 of the calendar year for...

  18. 40 CFR 85.2303 - Duration of model year.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Duration of model year. 85.2303... (CONTINUED) CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Determination of Model Year for Motor Vehicles and... Duration of model year. A specific model year must always include January 1 of the calendar year for...

  19. 40 CFR 85.2303 - Duration of model year.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Duration of model year. 85.2303... (CONTINUED) CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Determination of Model Year for Motor Vehicles and... Duration of model year. A specific model year must always include January 1 of the calendar year for...

  20. Internal Clock Processes and the Filled-Duration Illusion

    ERIC Educational Resources Information Center

    Wearden, John H.; Norton, Roger; Martin, Simon; Montford-Bebb, Oliver

    2007-01-01

    In 3 experiments, the authors compared duration judgments of filled stimuli (tones) with unfilled ones (intervals defined by clicks or gaps in tones). Temporal generalization procedures (Experiment 1) and verbal estimation procedures (Experiments 2 and 3) all showed that subjective durations of the tones were considerably longer than those of…

  1. 6 CFR 7.24 - Duration of classification.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 6 Domestic Security 1 2012-01-01 2012-01-01 false Duration of classification. 7.24 Section 7.24 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY CLASSIFIED NATIONAL SECURITY INFORMATION Classified Information § 7.24 Duration of classification. (a) At the time of...

  2. 6 CFR 7.24 - Duration of classification.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 6 Domestic Security 1 2011-01-01 2011-01-01 false Duration of classification. 7.24 Section 7.24 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY CLASSIFIED NATIONAL SECURITY INFORMATION Classified Information § 7.24 Duration of classification. (a) At the time of...

  3. 10 CFR 52.173 - Duration of manufacturing license.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Duration of manufacturing license. 52.173 Section 52.173... POWER PLANTS Manufacturing Licenses § 52.173 Duration of manufacturing license. A manufacturing license... issuance. A holder of a manufacturing license may not initiate the manufacture of a reactor less than...

  4. 10 CFR 52.173 - Duration of manufacturing license.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Duration of manufacturing license. 52.173 Section 52.173... POWER PLANTS Manufacturing Licenses § 52.173 Duration of manufacturing license. A manufacturing license... issuance. A holder of a manufacturing license may not initiate the manufacture of a reactor less than...

  5. 10 CFR 52.173 - Duration of manufacturing license.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Duration of manufacturing license. 52.173 Section 52.173... POWER PLANTS Manufacturing Licenses § 52.173 Duration of manufacturing license. A manufacturing license... issuance. A holder of a manufacturing license may not initiate the manufacture of a reactor less than...

  6. 10 CFR 52.173 - Duration of manufacturing license.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Duration of manufacturing license. 52.173 Section 52.173... POWER PLANTS Manufacturing Licenses § 52.173 Duration of manufacturing license. A manufacturing license... issuance. A holder of a manufacturing license may not initiate the manufacture of a reactor less than...

  7. 10 CFR 52.173 - Duration of manufacturing license.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Duration of manufacturing license. 52.173 Section 52.173... POWER PLANTS Manufacturing Licenses § 52.173 Duration of manufacturing license. A manufacturing license... issuance. A holder of a manufacturing license may not initiate the manufacture of a reactor less than...

  8. 42 CFR 61.38 - Duration of service fellowships.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Duration of service fellowships. 61.38 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....

  9. 42 CFR 61.13 - Duration and continuation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Duration and continuation. 61.13 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...

  10. 42 CFR 61.38 - Duration of service fellowships.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Duration of service fellowships. 61.38 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....

  11. 42 CFR 61.13 - Duration and continuation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Duration and continuation. 61.13 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...

  12. 42 CFR 61.38 - Duration of service fellowships.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Duration of service fellowships. 61.38 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....

  13. 42 CFR 61.13 - Duration and continuation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Duration and continuation. 61.13 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...

  14. 42 CFR 61.38 - Duration of service fellowships.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Duration of service fellowships. 61.38 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....

  15. 42 CFR 61.13 - Duration and continuation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Duration and continuation. 61.13 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...

  16. 42 CFR 61.38 - Duration of service fellowships.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Duration of service fellowships. 61.38 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....

  17. 42 CFR 61.13 - Duration and continuation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Duration and continuation. 61.13 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...

  18. 20 CFR 655.158 - Duration of positive recruitment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 3 2014-04-01 2014-04-01 false Duration of positive recruitment. 655.158... Employment in the United States (H-2A Workers) Post-Acceptance Requirements § 655.158 Duration of positive recruitment. Except as otherwise noted, the obligation to engage in positive recruitment described in §§...

  19. 20 CFR 655.158 - Duration of positive recruitment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 3 2012-04-01 2012-04-01 false Duration of positive recruitment. 655.158... Employment in the United States (H-2A Workers) Post-Acceptance Requirements § 655.158 Duration of positive recruitment. Except as otherwise noted, the obligation to engage in positive recruitment described in §§...

  20. Stimulus Duration Preference at Electrode Sites Yielding Elicited Behavior

    NASA Technical Reports Server (NTRS)

    Cox, V. C.

    1970-01-01

    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

  1. 20 CFR 617.15 - Duration of TRA.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 3 2012-04-01 2012-04-01 false Duration of TRA. 617.15 Section 617.15... FOR WORKERS UNDER THE TRADE ACT OF 1974 Trade Readjustment Allowances (TRA) § 617.15 Duration of TRA. (a) Basic weeks. An individual shall not be paid basic TRA for any week beginning after the close...

  2. 20 CFR 617.15 - Duration of TRA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Duration of TRA. 617.15 Section 617.15... FOR WORKERS UNDER THE TRADE ACT OF 1974 Trade Readjustment Allowances (TRA) § 617.15 Duration of TRA. (a) Basic weeks. An individual shall not be paid basic TRA for any week beginning after the close...

  3. 20 CFR 617.15 - Duration of TRA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Duration of TRA. 617.15 Section 617.15... FOR WORKERS UNDER THE TRADE ACT OF 1974 Trade Readjustment Allowances (TRA) § 617.15 Duration of TRA. (a) Basic weeks. An individual shall not be paid basic TRA for any week beginning after the close...

  4. 20 CFR 617.15 - Duration of TRA.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 3 2013-04-01 2013-04-01 false Duration of TRA. 617.15 Section 617.15... FOR WORKERS UNDER THE TRADE ACT OF 1974 Trade Readjustment Allowances (TRA) § 617.15 Duration of TRA. (a) Basic weeks. An individual shall not be paid basic TRA for any week beginning after the close...

  5. 20 CFR 617.15 - Duration of TRA.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 3 2014-04-01 2014-04-01 false Duration of TRA. 617.15 Section 617.15... FOR WORKERS UNDER THE TRADE ACT OF 1974 Trade Readjustment Allowances (TRA) § 617.15 Duration of TRA. (a) Basic weeks. An individual shall not be paid basic TRA for any week beginning after the close...

  6. 20 CFR 410.202 - Duration of entitlement; miner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Duration of entitlement; miner. 410.202 Section 410.202 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Requirements for Entitlement; Duration of...

  7. 20 CFR 410.213 - Duration of entitlement; child.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Duration of entitlement; child. 410.213 Section 410.213 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Requirements for Entitlement; Duration of...

  8. 25 CFR 211.27 - Duration of leases.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... duration shall be measured from the date of approval by the Secretary. (b) An oil and gas or geothermal resource lease which stipulates that it shall continue in full force and effect beyond the expiration of... duration without actual production of oil, gas, or geothermal resources. Provided, that this extension...

  9. 10 CFR 430.57 - Duration of temporary exemption.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Duration of temporary exemption. 430.57 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 according...

  10. 10 CFR 430.57 - Duration of temporary exemption.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Duration of temporary exemption. 430.57 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 according...

  11. 25 CFR 163.24 - Duration of timber contracts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Duration of timber contracts. 163.24 Section 163.24... Forest Management and Operations § 163.24 Duration of timber contracts. After the effective date of a... allowed for harvesting the estimated volume of timber purchased, shall be five years....

  12. 25 CFR 163.24 - Duration of timber contracts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Duration of timber contracts. 163.24 Section 163.24... Forest Management and Operations § 163.24 Duration of timber contracts. After the effective date of a... allowed for harvesting the estimated volume of timber purchased, shall be five years....

  13. 25 CFR 163.24 - Duration of timber contracts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Duration of timber contracts. 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 of...

  14. 25 CFR 163.24 - Duration of timber contracts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Duration of timber contracts. 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 of...

  15. 25 CFR 163.24 - Duration of timber contracts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Duration of timber contracts. 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 of...

  16. 5 CFR 831.642 - Marriage duration requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Marriage duration requirements. 831.642... REGULATIONS (CONTINUED) RETIREMENT Survivor Annuities Eligibility § 831.642 Marriage duration requirements. (a... in paragraph (b) of this section; or (2) A child was born of the marriage, as explained in...

  17. 5 CFR 831.642 - Marriage duration requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Marriage duration requirements. 831.642... REGULATIONS (CONTINUED) RETIREMENT Survivor Annuities Eligibility § 831.642 Marriage duration requirements. (a... in paragraph (b) of this section; or (2) A child was born of the marriage, as explained in...

  18. 5 CFR 843.303 - Marriage duration requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Marriage duration requirements. 843.303... Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The current spouse of a retiree, an... marriage, as explained in paragraph (c) of this section; or (3) The death of the retiree, employee,...

  19. 5 CFR 843.303 - Marriage duration requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Marriage duration requirements. 843.303... Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The current spouse of a retiree, an... marriage, as explained in paragraph (c) of this section; or (3) The death of the retiree, employee,...

  20. 5 CFR 843.303 - Marriage duration requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Marriage duration requirements. 843.303... Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The current spouse of a retiree, an... marriage, as explained in paragraph (c) of this section; or (3) The death of the retiree, employee,...

  1. 5 CFR 831.642 - Marriage duration requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Marriage duration requirements. 831.642... REGULATIONS (CONTINUED) RETIREMENT Survivor Annuities Eligibility § 831.642 Marriage duration requirements. (a... in paragraph (b) of this section; or (2) A child was born of the marriage, as explained in...

  2. 5 CFR 831.642 - Marriage duration requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Marriage duration requirements. 831.642... REGULATIONS (CONTINUED) RETIREMENT Survivor Annuities Eligibility § 831.642 Marriage duration requirements. (a... in paragraph (b) of this section; or (2) A child was born of the marriage, as explained in...

  3. 5 CFR 843.303 - Marriage duration requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Marriage duration requirements. 843.303... Former Spouse Benefits § 843.303 Marriage duration requirements. (a) The current spouse of a retiree, an... marriage, as explained in paragraph (c) of this section; or (3) The death of the retiree, employee,...

  4. 40 CFR 166.45 - Duration of crisis exemption.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Duration of crisis exemption. 166.45... EXEMPTION OF FEDERAL AND STATE AGENCIES FOR USE OF PESTICIDES UNDER EMERGENCY CONDITIONS Crisis Exemptions § 166.45 Duration of crisis exemption. A crisis exemption may be authorized for: (a) Only as long as...

  5. 40 CFR 166.45 - Duration of crisis exemption.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Duration of crisis exemption. 166.45... EXEMPTION OF FEDERAL AND STATE AGENCIES FOR USE OF PESTICIDES UNDER EMERGENCY CONDITIONS Crisis Exemptions § 166.45 Duration of crisis exemption. A crisis exemption may be authorized for: (a) Only as long as...

  6. 40 CFR 166.45 - Duration of crisis exemption.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Duration of crisis exemption. 166.45... EXEMPTION OF FEDERAL AND STATE AGENCIES FOR USE OF PESTICIDES UNDER EMERGENCY CONDITIONS Crisis Exemptions § 166.45 Duration of crisis exemption. A crisis exemption may be authorized for: (a) Only as long as...

  7. 40 CFR 166.45 - Duration of crisis exemption.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Duration of crisis exemption. 166.45... EXEMPTION OF FEDERAL AND STATE AGENCIES FOR USE OF PESTICIDES UNDER EMERGENCY CONDITIONS Crisis Exemptions § 166.45 Duration of crisis exemption. A crisis exemption may be authorized for: (a) Only as long as...

  8. 40 CFR 144.36 - Duration of permits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Duration of permits. 144.36 Section 144.36 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM Authorization by Permit § 144.36 Duration of permits. (a) Permits...

  9. 19 CFR 141.34 - Duration of power of attorney.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 2 2012-04-01 2012-04-01 false Duration of power of attorney. 141.34 Section 141.34 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power...

  10. 19 CFR 141.34 - Duration of power of attorney.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Duration of power of attorney. 141.34 Section 141.34 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power...

  11. 19 CFR 141.34 - Duration of power of attorney.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 2 2013-04-01 2013-04-01 false Duration of power of attorney. 141.34 Section 141.34 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power...

  12. 19 CFR 141.34 - Duration of power of attorney.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Duration of power of attorney. 141.34 Section 141.34 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power...

  13. 10 CFR 52.181 - Duration of renewal.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Duration of renewal. 52.181 Section 52.181 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Manufacturing Licenses § 52.181 Duration of renewal. A renewed manufacturing license may be issued for a term...

  14. 10 CFR 52.181 - Duration of renewal.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Duration of renewal. 52.181 Section 52.181 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Manufacturing Licenses § 52.181 Duration of renewal. A renewed manufacturing license may be issued for a term...

  15. 10 CFR 52.181 - Duration of renewal.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Duration of renewal. 52.181 Section 52.181 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Manufacturing Licenses § 52.181 Duration of renewal. A renewed manufacturing license may be issued for a term...

  16. 10 CFR 52.181 - Duration of renewal.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Duration of renewal. 52.181 Section 52.181 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Manufacturing Licenses § 52.181 Duration of renewal. A renewed manufacturing license may be issued for a term...

  17. 10 CFR 52.104 - Duration of combined license.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Duration of combined license. 52.104 Section 52.104 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.104 Duration of combined license. A combined license is issued for a...

  18. 10 CFR 52.104 - Duration of combined license.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Duration of combined license. 52.104 Section 52.104 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.104 Duration of combined license. A combined license is issued for a...

  19. 10 CFR 52.181 - Duration of renewal.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Duration of renewal. 52.181 Section 52.181 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Manufacturing Licenses § 52.181 Duration of renewal. A renewed manufacturing license may be issued for a term...

  20. 10 CFR 52.104 - Duration of combined license.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Duration of combined license. 52.104 Section 52.104 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.104 Duration of combined license. A combined license is issued for a...