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Sample records for qrs complex duration

  1. Rate-dependent variation in the duration of the QRS complex with left anterior fascicular block.

    PubMed

    Mirvis, D M; Bandura, J P; Brody, D A

    1977-10-01

    The case of a 67-year-old man with combined ischemic and valvular heart disease is presented. Electrocardiographic abnormalities included left anterior fascicular block with a variable duration of the QRS complex. The width of the QRS complex was dependent on the length of the cycle, being broader with short than with long preceding R-R intervals. This is interpreted as a tachycardia-dependent focal block coexisting with a fixed delay in fascicular conduction.

  2. Electrocardiogram voltage attenuation and shortening of the duration of P-waves, QRS complexes, and QT intervals.

    PubMed

    Madias, John E

    2013-01-01

    Multiple pathologies in concert may lead to attenuation of the electrocardiogram (ECG) voltage. A case of a patient illustrating the above is presented, who showed marked attenuation of the ECG voltage. Automated values of the amplitude of the ECG QRS complexes, P-waves, and T-waves (in mm), duration of the QRS complexes, P-waves, and QT intervals (in ms), in 2 ECGs were compared. The patient was a 64-year-old woman who developed in the setting of a fatal illness, pleural and pericardial effusions, pneumomediastinum, pneumoperitoneum, subcutaneous emphysema in the neck and chest, peripheral edema with weight gain of 43.4 lbs, marked hypoalbuminemia, abnormal liver tests, and renal failure. All the above pathologies led to a marked attenuation of the ECG voltage, and shortening of the mean P-wave, QRS complexes, and QTc interval durations. The postulated mechanism of the observed ECG phenomena is discussed.

  3. QRS duration versus morphology and survival after cardiac resynchronization therapy

    PubMed Central

    Khidir, Mand J.H.; Ajmone Marsan, Nina; Schalij, Martin J.; Bax, Jeroen J.

    2016-01-01

    Abstract Aims The prognostic implications of QRS duration and morphology in heart failure patients treated with cardiac resynchronization therapy (CRT) remains debated. The present evaluation investigated the association between QRS duration (<150 vs. ≥150 ms) and QRS morphology (left bundle brand block [LBBB] vs. non‐LBBB) and long‐term prognosis of a large cohort of unselected heart failure patients treated with CRT according to contemporary guidelines. Methods and results Of 973 heart failure patients treated with CRT (mean age 66.1 ± 9.8 years, 76% male), 658 patients (68%) showed QRS duration ≥150 ms, and 772 patients (79%) had LBBB configuration. Compared with patients with QRS duration <150 ms, patients with QRS duration ≥150 ms had less frequently ischaemic cardiomyopathy and atrial fibrillation and showed larger left ventricular volumes and lower left ventricular ejection fraction. Compared with patients with non‐LBBB configuration, patients with LBBB morphology were younger, less often males and less often had ischaemic cardiomyopathy and atrial fibrillation. On multivariable analysis, after correcting for relevant clinical and echocardiographic variables, LBBB morphology was significantly associated with better survival [hazard ratio (HR) 0.737; 95% confidence interval (CI) 0.584–0.931; P = 0.010], whereas there was no statistically significant association between QRS duration ≥150 ms and survival (HR 0.889; 95% CI 0.726–1.088; P = 0.252). Conclusions In this large population of heart failure patients treated with CRT, QRS morphology was independently associated with long‐term survival. The association between QRS duration and long‐term survival was not statistically significant. PMID:28217309

  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. Presence of Fragmented QRS Complexes in Patients with Obstructive Sleep Apnea Syndrome

    PubMed Central

    Sayin, Muhammet Rasit; Altuntas, Murat; Aktop, Ziyaeddin; Oz, Ibrahim I; Yavuz, Nesimi; Akpinar, Ibrahim; Sagatli, Erol; Karabag, Turgut; Aydin, Mustafa

    2015-01-01

    Background: Obstructive sleep apnea syndrome (OSAS) is a disease with increasing prevalence, which is mainly characterized by increased cardiopulmonary mortality and morbidity. It is well-known that OSAS patients have increased prevalence of cardiovascular diseases including coronary heart disease, heart failure, and arrhythmias. The aim of this study was to evaluate the presence of prolonged and fragmented QRS complexes, which have previously been associated with cardiovascular mortality, in OSAS patients. Methods: Our study included 51 patients (mean age 41.6 ± 10.1 years) who were recently diagnosed with OSAS (apnea-hypopnea index [AHI] ≥5 events/h) and never received therapy. The control group consisted of 34 volunteers (mean age 43.1 ± 11.6 years) in whom OSAS was excluded (AHI <5 events/h). The longest QRS complexes was measured in the 12-lead electrocardiogram (ECG) and the presence of fragmentation in QRS complexes was investigated. Results: Fragmented QRS frequency was significantly higher in patients with OSAS (n = 31 [61%] vs. n = 12 [35%], P = 0.021). QRS and QTc durations were also significantly longer in OSAS patients than controls (99.8 ± 13.9 ms vs. 84.7 ± 14.3 ms, P < 0.001; 411.4 ± 26.9 ms vs. 390.1 ± 32.2 ms, P = 0.001, respectively). Analysis of the patient and controls groups combined revealed a weak-moderate correlation between AHI and QRS duration (r = 0.292, P = 0.070). OSAS group had no correlation between AHI and QRS duration (r = −0.231, P = 0.203). Conclusions: In our study fragmented QRS frequency and QRS duration were found to increase in OSAS patients. Both parameters are related with increased cardiovascular mortality. Considering the prognostic importance of ECG parameters, it may be reasonable to recommend more detailed evaluation of OSAS patients with fragmented or prolonged QRS complexes with respect to presence of cardiovascular diseases. PMID:26265605

  6. QRS complex detection in ECG signal for wearable devices.

    PubMed

    Arefin, M Riadh; Tavakolian, Kouhyar; Fazel-Rezai, Reza

    2015-01-01

    This paper presents QRS complex detection algorithm based on dual slope technique, which is suitable for wearable electrocardiogram (ECG) applications. For cardiac patients of different arrhythmias, ECG signals are needed to be monitored over an extensive period of time. Thus, the wearable heart monitoring system needs computationally efficient QRS detection technique with good accuracy. In this paper, a method of QRS detection based on two slopes on both sides of an R peak is presented which is computationally efficient. Based on the slopes, first, a variable measuring steepness is developed, then by introducing an adjustable R-R interval based window and adaptive thresholding techniques, depending on the number of peaks detected in such window, R peaks are detected. The algorithm was evaluated against MIT/BIH arrhythmia database and achieved 99.16% detection rate with sensitivity of 0.9935 and positive predictivity of 0.9981. The method was compared with two widely used R peaks detection algorithms.

  7. 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.

  8. 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

  9. Computer simulation of the precordial QRS complex: effects of simulated changes in ventricular wall thickness and volume.

    PubMed

    Salu, Y; Marcus, M L

    1976-12-01

    The cardiac electric field generated by depolarization of the human ventricle is simulated with a computer model which utilizes 1,500 dipoles. The configuration of the ventricles utilized in the model assumed that the cross-sectional shape of the left ventricle was circular and the right ventricular free wall was a portion of an ellipse. The torso was assumed to be homogeneous and infinite. The activation sequence was based on the measurements of Durrer. The depolarizational wave was simulated by dipole layers. The output of the model is presented as a standard multilead precordial ECG. The ECG complexes generated by the model closely resemble the precordial QRS complexes of normal man. Simulated increases in wall thickness (1 to 2.2 X control) were associated with changes in the calculated precordial QRS complexes which were characteristic of left ventricular hypertrophy. Voltage (R in V5 or V6 and S in V1) and QRS duration increased linearly as a function of calculated left ventricular mass. Increases in ventricular activation time were related nonlinearly to changes in left ventricular mass and did not occur in the absence of a simulated increase in wall thickness. The effects of simulated changes in left ventricular volume (0.6 to 3.0 X control) on the QRS complex were mainly dependent on the resultant increase in left ventricular mass. This model may be useful in simulating the precordial QRS complexes that result from isolated or combined changes in ventricular volume or wall thickness or other disorders of the heart. Furthermore, it may be useful whenever a simulation of a QRS generator is needed.

  10. A new approach of QRS complex detection based on matched filtering and triangle character analysis.

    PubMed

    Li, Yanjun; Yan, Hong; Hong, Feng; Song, Jinzhong

    2012-09-01

    QRS complex detection usually provides the fundamentals to automated electrocardiogram (ECG) analysis. In this paper, a new approach of QRS complex detection without the stage of noise suppression was developed and evaluated, which was based on the combination of two techniques: matched filtering and triangle character analysis. Firstly, a template of QRS complex was selected automatically by the triangle character in ECG, and then it was time-reversed after removing its direct current component. Secondly, matched filtering was implemented at low computational cost by finite impulse response, which further enhanced QRS complex and attenuated non-QRS regions containing P-wave, T-wave and various noise components. Subsequently, triangle structure-based threshold decision was processed to detect QRS complexes. And RR intervals and triangle structures were further analyzed for the reduction of false-positive and false-negative detections. Finally, the performance of the proposed algorithm was tested on all 48 records of the MIT-BIH Arrhythmia Database. The results demonstrated that the detection rate reached 99.62 %, the sensitivity got 99.78 %, and the positive prediction was 99.85 %. In addition, the proposed method was able to identify QRS complexes reliably even under the condition of poor signal quality.

  11. 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

  12. Adaptive rule based fetal QRS complex detection using Hilbert transform.

    PubMed

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

    2009-01-01

    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.

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

    PubMed

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

    2015-07-01

    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.

  14. [Detection of QRS complexes using wavelet transformation and golden section search algorithm].

    PubMed

    Chen, Wenli; Mo, Zhiwen; Guo, Wen

    2009-08-01

    The extraction and identification of ECG (electrocardiogram) signal characteristic parameters are the basis of ECG analysis and diagnosis. The fast and precise detection of QRS complexes is very important in ECG signal analysis; for it is a pre-requisite for the correlative parameters calculation as well as for correct diagnosis. In our work, firstly, the modulus maximum of wavelet transform is applied to the QRS complexes detection from ECG signal. Once there are mis-detections or missed detections happening, we utilize the Golden Section Search algorithm to adjust the threshold of maxima determination. The correct detection rate of the QRS complexes is up to 99.6% based on MIT-BIH ECG data.

  15. 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.

  16. 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.

  17. 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.

  18. Short-term Prognosis of Fragmented QRS Complex in Patients with Non-ST Elevated Acute Myocardial Infarction

    PubMed Central

    Li, Min; Wang, Xiao; Mi, Shu-Hua; Chi, Zhe; Chen, Qing; Zhao, Xin; Nie, Shao-Ping

    2016-01-01

    Background: There remains significant debate as to the relationship between fragmented QRS (fQRS) complexes on electrocardiogram (ECG) and acute myocardial infarction (AMI). Few studies have reported on this relationship in non-ST elevated AMI (NSTEMI), and thus, we attempt to assess this relationship and its potential short-term prognostic value. Methods: This was a single-center, observational, retrospective cohort study. A total of 513 consecutive patients (399 men, 114 women) with NSTEMI within 24 h who underwent coronary angiography at our department, between January 1, 2014, and December 31, 2014. Patients were divided into 2 groups according to the presence or absence of fQRS complex on the admission ECG. fQRS complexes were defined as the existence of an additional R’ or crochetage wave, notching in the nadir of the S wave, RS fragmentation, or QS complexes on 2 contiguous leads. All patients were followed up for 6 months, and all major adverse cardiac events (MACE) were recorded. Results: In this study, there were 285 patients with fQRS ECG in the 513 patients with NSTEMI. The number of patients with 0–2 coronary arteries narrowed by ≥50% in fQRS group were less while patients with 3 narrowed arteries were more than in the non-fQRS group (P = 0.042). There were fewer Killip Class I patients in the fQRS group (P = 0.019), while Killip Class II, III, and IV patients were more in the fQRS group than in the non-fQRS group (P = 0.019). Left ventricular ejection fraction levels were significantly lower in the fQRS group (P = 0.021). Baseline total cholesterol, low-density lipoprotein, creatinine, creatine kinase, homocysteine, high-sensitivity C-reactive protein (CRP), and red blood cells distribution width levels were significantly higher in the fQRS group. Total MACE (MACE, P = 0.028), revascularization (P = 0.005), and recurrent angina (P = 0.005) were also significantly greater in the fQRS group. On final logistic regression analysis, after adjusting

  19. Two pacing spikes on the QRS complex in a single-chamber pacemaker

    PubMed Central

    Choudhary, Dinesh; Sundaram, Shunmuga; Thajudeen, Anees; Namboodiri, Narayanan

    2012-01-01

    AutoCapture algorithm helps the pacemakers to automatically adjust output close to the pacing threshold. This algorithm monitors the evoked response signal of myocardial depolarization, and delivers a high output back-up pulse if there is a loss of capture. This case, with two pacemaker spikes on the QRS complexes in a patient with VVI pacemaker, simulating a sensing failure, demands clear understanding of AutoCapture function before labeling the pacemaker malfunction. PMID:23102397

  20. Why QRS Duration Should Be Replaced by Better Measures of Electrical Activation to Improve Patient Selection for Cardiac Resynchronization Therapy.

    PubMed

    Engels, Elien B; Mafi-Rad, Masih; van Stipdonk, Antonius M W; Vernooy, Kevin; Prinzen, Frits W

    2016-08-01

    Cardiac resynchronization therapy (CRT) is a well-known treatment modality for patients with a reduced left ventricular ejection fraction accompanied by a ventricular conduction delay. However, a large proportion of patients does not benefit from this therapy. Better patient selection may importantly reduce the number of non-responders. Here, we review the strengths and weaknesses of the electrocardiogram (ECG) markers currently being used in guidelines for patient selection, e.g., QRS duration and morphology. We shed light on the current knowledge on the underlying electrical substrate and the mechanism of action of CRT. Finally, we discuss potentially better ECG-based biomarkers for CRT candidate selection, of which the vectorcardiogram may have high potential.

  1. A new method for QRS complex detection in multichannel ECG: Application to self-monitoring of fetal health.

    PubMed

    Varanini, Maurizio; Tartarisco, Gennaro; Balocchi, Rita; Macerata, Alberto; Pioggia, Giovanni; Billeci, Lucia

    2016-04-13

    This paper proposes a new approach for QRS complex detection in multichannel ECG and presents its application to fetal QRS (fQRS) detection in signals acquired from maternal abdominal leads. The method exploits the characteristics of pseudo-periodicity and time shape of QRS, it consists of devising a quality index (QI) which synthesizes these characteristics and of finding the linear combination of the acquired ECGs, which maximizes this QI. In the application for fQRS detection two QIs are devised, one QI (mQI) for maternal ECG (mECG) and one QI (fQI) for fetal ECG (fECG). The method is completely unsupervised and based on the following steps: signal pre-processing; maternal QRS-enhanced signal extraction by finding the linear combination that maximize the mQI; detection of maternal QRSs; mECG component approximation and canceling by weighted Singular Value Decomposition (SVD); fQRS-enhanced signal extraction by finding the linear combination that maximize the fQI and fQRS detection. The proposed method was compared with our previously developed Independent Component Analysis (ICA) based method as well as with simple mECG canceling and simple ICA methods. The comparison was carried out by evaluating the performances of the procedures in fQRS detection. The new method outperformed the results of the other approaches on the annotated open set of the Computing in Cardiology Challenge 2013 database. The proposed method seems to be promising for its implementation on portable device and for use in self-monitoring of fetal health in pregnant women.

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

    PubMed Central

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

    2011-01-01

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

  3. 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

  4. Modeling and visualization of the activation wavefront propagation to improve understanding the QRS complex changes indicating left ventricular hypertrophy.

    PubMed

    Svehlikova, Jana; Zelinka, Jan; Bacharova, Ljuba; Tysler, Milan

    2016-01-01

    % increase of the thickness of the left ventricular wall, did not cause prolongation of the QRS complex out of normal range. Considerable prolongation of the QRS complex duration was observed only for transmural slowing of the propagation velocity to 25% of its reference value in large ventricular areas or for combination of such slowing with the left ventricular hypertrophy.

  5. 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.

  6. Predictive value of the fragmented QRS complex in 6-month mortality and morbidity following acute coronary syndrome

    PubMed Central

    Akbarzadeh, Fariborz; Pourafkari, Leili; Ghaffari, Samad; Hashemi, Mohammad; Sadeghi-Bazargani, Homayoun

    2013-01-01

    Background Fragmented QRS encompasses different RSR’ patterns showing various morphologies of the QRS complexes with or without the Q wave on a resting 12-lead electrocardiogram. It has been shown possibly to cause adverse cardiac outcomes in patients with some heart diseases, including coronary artery disease. In view of the need for risk stratification of patients presenting with acute coronary syndrome in the most efficacious and cost-effective way, we conducted this study to clarify the value of developing fragmented QRS in a cohort of patients presenting with their first acute coronary syndrome in predicting 6-month mortality and morbidity. Methods One hundred consecutive patients admitted to the coronary care unit at Shahid Madani Heart Center in Tabriz from December 2008 to March 2009 with their first acute coronary syndrome were enrolled in this prospective study. Demographic and electrocardiographic data on admission, inhospital mortality, and need for revascularization were recorded. Electrocardiography performed 2 months after the index event was examined for development of fragmented QRS. Mortality and morbidity was evaluated at 6-month follow-up in all patients. Results The patients were of mean age 57.7 ± 12.8 years, and 84% were men. The primary diagnosis was unstable angina in 17 (17%) patients, non-ST elevation myocardial infarction (MI) in 11 (11%), anterior or inferior ST elevation MI in 66 (66%), and postero-inferior MI in six (6%). Fragmented QRS was present in 30 (30%) patients during the first admission, which increased to 44% at the 2-month follow-up and to 53% at the 6-month follow-up. The presence of various coronary risk factors and drug therapy given, including fibrinolytic agents, had no effect on development of fragmented QRS. Mortality was significantly higher (P = 0.032) and left ventricular ejection fraction was significantly lower (P = 0.001) in the fragmented QRS group at the 6-month follow-up. Conclusion This study strongly

  7. Human ventricular activation sequence and the simulation of the electrocardiographic QRS complex and its variability in healthy and intraventricular block conditions

    PubMed Central

    Cardone-Noott, Louie; Bueno-Orovio, Alfonso; Mincholé, Ana; Zemzemi, Nejib; Rodriguez, Blanca

    2016-01-01

    Aims To investigate how variability in activation sequence and passive conduction properties translates into clinical variability in QRS biomarkers, and gain novel physiological knowledge on the information contained in the human QRS complex. Methods and results Multiscale bidomain simulations using a detailed heart-torso human anatomical model are performed to investigate the impact of activation sequence characteristics on clinical QRS biomarkers. Activation sequences are built and validated against experimentally-derived ex vivo and in vivo human activation data. R-peak amplitude exhibits the largest variability in terms of QRS morphology, due to its simultaneous modulation by activation sequence speed, myocardial intracellular and extracellular conductivities, and propagation through the human torso. QRS width, however, is regulated by endocardial activation speed and intracellular myocardial conductivities, whereas QR intervals are only affected by the endocardial activation profile. Variability in the apico-basal location of activation sites on the anterior and posterior left ventricular wall is associated with S-wave progression in limb and precordial leads, respectively, and occasional notched QRS complexes in precordial derivations. Variability in the number of early activation sites successfully reproduces pathological abnormalities of the human conduction system in the QRS complex. Conclusion Variability in activation sequence and passive conduction properties captures and explains a large part of the clinical variability observed in the human QRS complex. Our physiological insights allow for a deeper interpretation of human QRS biomarkers in terms of QRS morphology and location of early endocardial activation sites. This might be used to attain a better patient-specific knowledge of activation sequence from routine body-surface electrocardiograms. PMID:28011826

  8. 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.

  9. Frequency of fragmented QRS in patient with psoriasis vulgaris without cardiovascular disease.

    PubMed

    Baş, Yalçın; Altunkaş, Fatih; Seçkin, Havva Yıldız; Takcı, Zennure; Arısoy, Arif; Karayakalı, Metin; Karaman, Kayıhan; Demir, Osman

    2016-07-01

    Myocardial fibrosis causes the fragmentation of QRS complexes on electrocardiogram. We hypothesized that the frequency of fragmented QRS (fQRS) could be more common in patients with psoriasis vulgaris than in healthy control subjects. In this prospective study, 100 patients with psoriasis vulgaris who did not have any cardiovascular disease were compared with 50 healthy volunteers in control group. The Psoriasis Area Severity Index (PASI) was used for expressing the severity of psoriasis. Patients with psoriasis were categorized according to presence of fQRS in ECG [fQRS (+) group and fQRS (-) group]. Patients with psoriasis had higher frequency of fQRS, higher levels of C reactive protein (CRP) and sedimentation rate (ESR) than the control group (n = 49, 49 % vs. n = 3, 6 %, p < 0.001; 9.91 ± 17.86 vs. 3.59 ± 0.79 mg/dL, p = 0.014; 17.37 ± 17.40 vs. 5.66 ± 5.22 mm/h, p < 0.001, respectively). Within the patient group there was no statistically significant difference between fQRS (+) and fQRS (-) subgroups with regards to sex, disease duration, CRP, ESR, medications and PASI score. It was suggested that presence of fQRS in ECG may be related with myocardial fibrosis in patients with psoriasis who do not have cardiovascular disease. For this reason, in our opinion, fQRS could be used as a predictive marker for myocardial fibrosis in patients with psoriasis.

  10. 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.

  11. 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.

  12. [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.

  13. Comparison of the relation between left ventricular anatomy and QRS duration in patients with cardiomyopathy with versus without left bundle branch block.

    PubMed

    Chan, Dulciana D; Wu, Katherine C; Loring, Zak; Galeotti, Loriano; Gerstenblith, Gary; Tomaselli, Gordon; Weiss, Robert G; Wagner, Galen S; Strauss, David G

    2014-05-15

    QRS duration (QRSd) is used to diagnose left bundle branch block (LBBB) and is important to determine cardiac resynchronization therapy eligibility. The same QRSd thresholds established decades ago are used for all patients. However, significant interpatient variability of normal QRSd exists, and individualized QRSd thresholds might improve diagnosis and intervention strategies. Previous work reported left ventricular (LV) mass and papillary muscle location predicted QRSd in healthy subjects, but the relation in diseased ventricles is unknown. The aim of the present study was to determine the association between LV anatomy and QRSd in patients with cardiomyopathy. Patients referred for primary prevention implantable defibrillators (n = 166) received cardiac magnetic resonance imaging, and those with normal conduction (without bundle branch or fascicular block) and LBBB were studied. The LV mass, length, internal diameter, LV end-diastolic volume, septal and lateral wall thicknesses, and papillary muscle location were measured. In patients with normal conduction, LV length (r = 0.35, p <0.001), mass (r = 0.32, p <0.001), diameter (r = 0.20, p = 0.03), and septal wall thickness (r = 0.20, p = 0.03) had positive correlations with QRSd. In patients with LBBB, LV length (r = 0.32, p = 0.03), mass (r = 0.39, p = 0.01), diameter (r = 0.34, p = 0.02), and LV end-diastolic volume (r = 0.32, p = 0.04) had positive correlations with QRSd. Contrary to previous studies in healthy subjects, papillary muscle angle (location) was not associated with QRSd in cardiomyopathy patients with normal conduction or LBBB. In conclusion, increasing LV anatomical measurements were associated with increasing QRSd in patients with cardiomyopathy. Future work should investigate the use of LV anatomical measurements in developing individualized QRSd thresholds for diagnosing conduction abnormalities such as LBBB and identifying candidates for cardiac resynchronization therapy.

  14. 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

  15. 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

  16. 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

  17. Fragmented QRS as a Marker of Electrical Dyssynchrony to Predict Inter-Ventricular Conduction Defect by Subsequent Echocardiographic Assessment in Symptomatic Patients of Non-Ischemic Dilated Cardiomyopathy

    PubMed Central

    Sinha, Santosh Kumar; Bhagat, Kush; Asif, Mohammad; Singh, Karandeep; Sachan, Mohit; Mishra, Vikas; Afdaali, Nasar; Jha, Mukesh Jitendra; Kumar, Ashutosh; Singh, Shravan; Sinha, Rupesh; Khanra, Dibbendhu; Thakur, Ramesh; Varma, Chandra Mohan; Krishna, Vinay; Pandey, Umeshwar

    2016-01-01

    Background Left ventricular (LV) dyssynchrony frequently occurs in patients with heart failure (HF). QRS ≥ 120 ms is a surrogate marker of electrical dyssynchrony, which occurs in only 30% of HF patients. In contrary, in those with normal QRS (nQRS) duration, LV dyssynchrony has been reported in 20-50%. This study was carried out to investigate the role of fragmented QRS (fQRS) on the surface electrocardiography (ECG) as a marker of electrical dyssynchrony to predict the presence of significant intraventricular dyssynchrony (IVD) by subsequent echocardiographic assessment. Methods A total of 226 consecutive patients with non-ischemic cardiomyopathy were assessed for fQRS on surface ECG as defined by presence of an additional R wave (R prime), notching in nadir of the S wave, notching of R wave, or the presence of more than one R prime (fragmentation) in two contiguous leads corresponding to a major myocardial segment. Tissue Doppler imaging (TDI) was performed in the apical views (four-chamber, two-chamber and long-axis) to analyze all 12 segments at both basal and middle levels. Time-to-peak myocardial sustained systolic (Ts) velocities were calculated. Significant systolic IVD was defined as Ts-SD > 32.6 ms as known as “Yu index”. Result Of the total patients, 112 had fQRS (49.5%), while 114 had nQRS (50.5%) with male dominance (M/F = 71:29). Majority of patients were in NYHA class II (n = 122, 54%) followed by class III (n = 83; 37%), and class IV (n = 21; 9%). There were no significant differences among both groups for baseline parameters except higher QRS duration (102.42 ± 14.05 vs. 91.10 ± 13.75 ms; P = 0.001), higher Yu index (35.64 ± 12.79 vs. 20.45 ± 11.17; P = 0.01) and number of patients with positive Yu index (78.6% vs. 21.1%; P = 0.04) in group with fQRS compared with group with nQRS. fQRS complexes had 84.61% sensitivity and 80.32% specificity with positive predictive value of 78.6% and negative predictive value of 85.9% to detect IVD. On

  18. The timing of onset of mechanical systole and diastole in reference to the QRS-T complex: a study to determine performance criteria for a non-invasive diastolic timed vibration massage system in treatment of potentially unstable cardiac disorders.

    PubMed

    Gill, Harjit; Hoffmann, Andrew

    2010-12-01

    Our institution is in development of a low frequency, non-invasive Diastolic Timed Vibrator (DTV) for use in emergency treatment of ST Elevation Myocardial Infarction (STEMI). It is preferable to avoid vibration emissions during the IsoVolumetric Contraction Period (IVCP) and at least the majority of mechanical systole thereafter, as systolic vibration may cause a negative inotropic effect in the ischemic heart. Furthermore diastolic vibration should preferably include the IsoVolumetric Relaxation Period (IVRP) which has been shown in clinical studies to improve cardiac performance and enhance coronary flow. Electrocardiographic (ECG) monitoring can be used to enable diastolic tracking, however, the timing of the phases of the cardiac cycle in relation to the ECG waveform must first be verified. The objective of this study was therefore to determine timing of onset of mechanical systole and diastole in reference to the QRS-T Complex. One hundred and twenty-three adult echocardiographic studies were assessed for the point of mitral and aortic valve closure in relation to the QRS complex and T wave in a representative population. We found that onset of mechanical systole occurred on and usually shortly after the peak of a first dominant QRS complex deflection, and onset of diastole occurred at the earliest on and most commonly beyond the peak or midpoint of the T wave. A DTV should ideally be able to stop vibrating on or before the peak of the first dominant deflection of a QRS complex, and begin vibrating near the peak of the T wave. Given early detection of ventricular depolarization can occur 10-20 ms prior to R wave peak, it is proposed that a DTV should preferably be able to stop vibrating within 10 ms of a triggered stop command. Onset of vibration during peak of T wave could be approximated by a rate adapted Q-T interval regression equation, and then fine tuned by manual adjustment during therapy.

  19. 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.

  20. 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.

  1. Unusual QRS morphology on ECG: a rare condition and an interesting response to pacing.

    PubMed

    Gula, Lorne J; Eckart, Robert E; Klein, George J; Peralta, Adelqui

    2005-08-01

    We present the interesting case of a young man with borderline wide QRS complexes noted on electrocardiogram (ECG). The diagnosis of an unusual form of preexcitation was reached using observations from intracardiac tracings at electrophysiology study. Atrial pacing consistently resulted in further widening of the first conducted QRS complex, and the physiology underlying this unusual finding is explored.

  2. Microcontroller-based real-time QRS detection.

    PubMed

    Sun, Y; Suppappola, S; Wrublewski, T A

    1992-01-01

    The authors describe the design of a system for real-time detection of QRS complexes in the electrocardiogram based on a single-chip microcontroller (Motorola 68HC811). A systematic analysis of the instrumentation requirements for QRS detection and of the various design techniques is also given. Detection algorithms using different nonlinear transforms for the enhancement of QRS complexes are evaluated by using the ECG database of the American Heart Association. The results show that the nonlinear transform involving multiplication of three adjacent, sign-consistent differences in the time domain gives a good performance and a quick response. When implemented with an appropriate sampling rate, this algorithm is also capable of rejecting pacemaker spikes. The eight-bit single-chip microcontroller provides sufficient throughput and shows a satisfactory performance. Implementation of multiple detection algorithms in the same system improves flexibility and reliability. The low chip count in the design also favors maintainability and cost-effectiveness.

  3. Complexity and Multifractal of Volatility Duration for Agent-Based Financial Dynamics and Real Markets

    NASA Astrophysics Data System (ADS)

    Yang, Ge; Wang, Jun

    2016-11-01

    A random agent-based financial model is developed and investigated by the finite-range multitype contact dynamic system, in an attempt to reproduce and study the dynamics of financial markets. And an analysis method of detecting duration and intensity relationship in volatility series is introduced, called the volatility duration analysis. Then the auto-correlation analysis suggests that there exists evident volatility clustering feature in absolute volatility durations for the simulation data and the real data. Besides, the Lempel-Ziv complexity analysis is applied to study the complexity of the returns, the corresponding absolute returns and the volatility duration returns, which can reflect the fluctuation behaviors, the volatility behaviors and the volatility duration behaviors. At last, the multifractal phenomena of volatility durations of returns are comparatively studied for Shanghai Composite Index and the proposed model by multifractal detrended fluctuation analysis.

  4. Ebstein Anomaly With QRS Fragmentation on Electrocardiogram

    PubMed Central

    Acharya, Prakash; Ang, Jonathan Ross; Gitler, Bernard

    2017-01-01

    Ebstein anomaly is a rare congenital disorder that involves the tricuspid valve and the right ventricle. It is associated with interatrial communication, which allows for paradoxical embolization causing unilateral blindness. Abnormal conduction through the atrialized right ventricle leads to QRS fragmentation on electrocardiogram. Its presence suggests a more severe abnormality and a higher risk of arrhythmia. The QRS fragmentation disappears after corrective surgery with resection of the atrialized right ventricle. PMID:28203575

  5. Ebstein Anomaly With QRS Fragmentation on Electrocardiogram.

    PubMed

    Acharya, Prakash; Ang, Jonathan Ross; Gitler, Bernard

    2017-01-01

    Ebstein anomaly is a rare congenital disorder that involves the tricuspid valve and the right ventricle. It is associated with interatrial communication, which allows for paradoxical embolization causing unilateral blindness. Abnormal conduction through the atrialized right ventricle leads to QRS fragmentation on electrocardiogram. Its presence suggests a more severe abnormality and a higher risk of arrhythmia. The QRS fragmentation disappears after corrective surgery with resection of the atrialized right ventricle.

  6. Dramatic Response to Cardiac Resynchronization Therapy With AV Delay Optimization in Narrow QRS Heart Failure.

    PubMed

    Kogawa, Rikitake; Nakai, Toshiko; Ikeya, Yukitoshi; Mano, Hiroaki; Sonoda, Kazumasa; Sasaki, Naoko; Iso, Kazuki; Okumura, Yasuo; Ohkubo, Kimie; Kunimoto, Satoshi; Watanabe, Ichiro; Hirayama, Atsushi

    2015-01-01

    Cardiac resynchronization therapy (CRT) has been shown to be effective for heart failure. However, as outlined in the AHA/ACC/HRS Appropriate Use Criteria, CRT is not strongly recommended for patients with a narrow QRS complex. We describe a case of dilated cardiomyopathy and narrow QRS complex in which we obtained a dramatic response to CRT by optimizing the atrioventricular (AV) delay. The patient was a 61-year-old man with intractable heart failure. Echocardiography showed a low ejection fraction of 22% but no dyssynchrony. Because he had been hospitalized many times for congestive heart failure despite β-blocker and diuretic treatment, we decided to use CRT. However, after implantation of the CRT device, the QRS complex widened abnormally, and his symptoms worsened. He was re-admitted 2 months after CRT implantation. We examined the pacemaker status and optimized the AV delay to obtain a "narrow" QRS complex. The patient's condition improved dramatically after the AV delay optimization. His clinical status has been good, and there has been no subsequent hospitalization. Our case points to the effectiveness of CRT in patients with a narrow QRS complex and to the importance of AV optimization for successful CRT.

  7. Factors affecting the duration effect in pitch perception for unresolved complex tones

    NASA Astrophysics Data System (ADS)

    White, Louise J.; Plack, Christopher J.

    2003-12-01

    Previous research has shown that fundamental frequency (F0) discrimination thresholds for complex tones containing unresolved harmonics decrease as the duration of the tone increases [White and Plack, J. Acoust. Soc. Am. 103, 2051-2063 (1998)]. In this paper F0 discrimination was measured as a function of duration for complexes with F0s of 62.5, 125, and 250 Hz, bandpass filtered into two spectral regions (2750-3750 and 5500-7500 Hz). The harmonics were summed either in sine phase (SINE) or with alternating sine-cosine phase (ALT), which affects the envelope of the waveform and the pitch of the complex. Tone duration was 20, 40, 80, and 160 ms. The improvement in F0 discrimination with duration increased with decreasing F0. When harmonics where spectrally filtered between 2750 and 3750 Hz, for complexes with an F0 of 62.5 Hz, F0 discrimination thresholds decreased from approximately 30% for a 20-ms tone to approximately 3% for a 160-ms tone. For complexes with an F0 of 250 Hz, thresholds decreased from 3% for a 20-ms tone to 1% for a 160-ms tone: a lower envelope repetition rate led to a larger change in performance with increasing duration. The phase manipulation also affected the size of the duration effect, in that the effect was less for an ALT complex compared to a SINE complex with the same F0, consistent with the change in envelope repetition rate. Overall, the results suggest that for unresolved complex tones it is primarily envelope repetition rate, not spectral region, that determines both the F0 discrimination threshold and the size of the duration effect.

  8. Intra-QRS Spectral Changes Accompany ST Segment Changes During Episodes of Myocardial Ischemia

    PubMed Central

    Gramatikov, Boris; Iyer, Vivek

    2014-01-01

    Background Coronary artery disease and myocardial ischemia cause substantial morbidity and mortality. While ischemia is traditionally diagnosed on the 12-lead electrocardiogram (ECG) by shifts in the ST segment, electrical changes are also produced within the QRS complex during depolarization of ischemic ventricular tissue, though these are often of small amplitude and can be missed in traditional ECG analysis. We explore the utility of an easily implemented spectral analysis method for detecting intra-QRS changes during episodes of myocardial ischemia, using Holter recordings from the European ST-T database. Methods Time-frequency distributions of QRS complexes from each recording were computed using the continuous wavelet transform. Indices corresponding to frequency content of four overlapping frequency bands were computed: F1 (24–35 Hz), F2 (30–45 Hz), F3 (40–60 Hz), and F4 (50–80 Hz). Values of these indices were compared during annotated episodes of ST change and during a baseline during the recording. Results Marked changes in intra-QRS frequency content were identified during ischemia, grouped by ECG lead analyzed. In lead III, a pronounced and statistically significant increase in the highest frequency sub-bands (F3 and F4) was consistently observed. Analysis of anterior precordial leads also showed significant increases in F4. Conclusions Intra-QRS time-frequency analysis using the continuous wavelet transform can identify a spectral signature corresponding to myocardial ischemia in the range 24–80 Hz. Intra-QRS spectral analysis has the potential for many clinical applications. PMID:25266140

  9. Analysis of Abnormal Intra-QRS Potentials in Signal-Averaged Electrocardiograms Using a Radial Basis Function Neural Network.

    PubMed

    Lin, Chun-Cheng

    2016-09-27

    Abnormal intra-QRS potentials (AIQPs) are commonly observed in patients at high risk for ventricular tachycardia. We present a method for approximating a measured QRS complex using a non-linear neural network with all radial basis functions having the same smoothness. We extracted the high frequency, but low amplitude intra-QRS potentials using the approximation error to identify possible ventricular tachycardia. With a specified number of neurons, we performed an orthogonal least squares algorithm to determine the center of each Gaussian radial basis function. We found that the AIQP estimation error arising from part of the normal QRS complex could cause clinicians to misjudge patients with ventricular tachycardia. Our results also show that it is possible to correct this misjudgment by combining multiple AIQP parameters estimated using various spread parameters and numbers of neurons. Clinical trials demonstrate that higher AIQP-to-QRS ratios in the X, Y and Z leads are visible in patients with ventricular tachycardia than in normal subjects. A linear combination of 60 AIQP-to-QRS ratios can achieve 100% specificity, 90% sensitivity, and 95.8% total prediction accuracy for diagnosing ventricular tachycardia.

  10. QRS Fragmentation Patterns Representing Myocardial Scar Need to Be Separated from Benign Normal Variants: Hypotheses and Proposal for Morphology based Classification

    PubMed Central

    Haukilahti, M. Anette E.; Eranti, Antti; Kenttä, Tuomas; Huikuri, Heikki V.

    2016-01-01

    The presence of a fragmented QRS complex (fQRS) in two contiguous leads of a standard 12-lead electrocardiogram (ECG) has been shown to be an indicator of myocardial scar in multiple different populations of cardiac patients. QRS fragmentation is also a predictor of adverse prognosis in acute myocardial infarction, coronary artery disease, and ischemic cardiomyopathy and a prognostic tool in structural heart diseases. An increased risk of sudden cardiac death associated with fQRS has been documented in patients with ischemic cardiomyopathy and hypertrophic cardiomyopathy. However, fQRS is also frequently observed in apparently healthy subjects. Thus, a more detailed classification of different QRS fragmentations is needed to identify the pathological fragmentation patterns and refine the role of fQRS as a risk marker of adverse cardiac events and sudden cardiac death. In most studies fQRS has been defined by the presence of an additional R wave (R′), or notching in the nadir of the S wave, or the presence of >1 R′ in two contiguous leads corresponding to a major coronary territory. However, this approach does not discriminate between minor and major fragmentations and the location of the fQRS is also neglected. In addition to this, the method is susceptible to large interobserver variability. We suppose that some fQRS subtypes result from conduction delays in the His-Purkinje system, which is a benign finding and thus can weaken the prognostic values of fQRS. The classification of fQRSs to subtypes with unambiguous definitions is needed to overcome the interobserver variability related issues and to separate fQRSs caused by myocardial scarring from benign normal variants. In this paper, we review the anatomic correlates of fQRS and the current knowledge of prognostic significance of fQRS. We also propose a detailed fQRS classification for research purposes which can later be simplified after the truly pathological morphologies have been identified. The research

  11. QRS Fragmentation Patterns Representing Myocardial Scar Need to Be Separated from Benign Normal Variants: Hypotheses and Proposal for Morphology based Classification.

    PubMed

    Haukilahti, M Anette E; Eranti, Antti; Kenttä, Tuomas; Huikuri, Heikki V

    2016-01-01

    The presence of a fragmented QRS complex (fQRS) in two contiguous leads of a standard 12-lead electrocardiogram (ECG) has been shown to be an indicator of myocardial scar in multiple different populations of cardiac patients. QRS fragmentation is also a predictor of adverse prognosis in acute myocardial infarction, coronary artery disease, and ischemic cardiomyopathy and a prognostic tool in structural heart diseases. An increased risk of sudden cardiac death associated with fQRS has been documented in patients with ischemic cardiomyopathy and hypertrophic cardiomyopathy. However, fQRS is also frequently observed in apparently healthy subjects. Thus, a more detailed classification of different QRS fragmentations is needed to identify the pathological fragmentation patterns and refine the role of fQRS as a risk marker of adverse cardiac events and sudden cardiac death. In most studies fQRS has been defined by the presence of an additional R wave (R'), or notching in the nadir of the S wave, or the presence of >1 R' in two contiguous leads corresponding to a major coronary territory. However, this approach does not discriminate between minor and major fragmentations and the location of the fQRS is also neglected. In addition to this, the method is susceptible to large interobserver variability. We suppose that some fQRS subtypes result from conduction delays in the His-Purkinje system, which is a benign finding and thus can weaken the prognostic values of fQRS. The classification of fQRSs to subtypes with unambiguous definitions is needed to overcome the interobserver variability related issues and to separate fQRSs caused by myocardial scarring from benign normal variants. In this paper, we review the anatomic correlates of fQRS and the current knowledge of prognostic significance of fQRS. We also propose a detailed fQRS classification for research purposes which can later be simplified after the truly pathological morphologies have been identified. The research

  12. [Expert assessment of operations' complexity and its interrelationship with lethal outcomes and duration of treatment].

    PubMed

    Bokeriia, L A; Samorodskaia, I V; Skopin, I I; Mironenko, V A; Kambarov, S Iu; Myrzakulov, E S

    2010-01-01

    The aim of the work was to carry out expert assessment of complexity of operations and to study interrelationship of the average score of complexity of the interventions with lethal outcome and duration of treatment in the Intensive Care Unit (exemplified by comparison with the outcomes of operations on cardiac valves performed in 2009 in the setting of artificial circulation in adult patients). Complexity was assessed by a total of 13 cardiovascular surgeons specialized in operations aimed at correcting valve defects (4 of them were from the A. N. Bakulev Scientific Centre for Cardiovascular Surgery), with none of the participants being aware of the therapeutic outcomes of each type of the operation performed. An average expert-defined score was assigned for each of the 33 names of the operations. The Kendall coefficient of concordance for all operations amounted to 0.29 (p<0.001); consensus in the complexity-score (from 69 to 85%) was achieved for 48.5% of the operations thus considered. The values of the mean scores of complexity of operations, defined by the specialists form the SCCS (2.02±0.54) were significantly lower (Wilcoxon's test; p<0.001) as compared with the average score assigned by specialists from other facilities (2.28±0.43). The duration of the stay at the ICU of the patients subdivided into groups depending on the expert score was found to differ significantly (p=0.007). The area under the ROC curve using the EuroSCORE (0.59) is suggestive of its lower accuracy in assessing the lethal outcome as compared to the expert score (0.68). The obtained findings strongly suggest advisability of using expert score of operations' complexity for solving complicated non-formalized tasks on allied problems of cardiovascular surgery and organization of public health care (accrediting of medical facilities, formation of the government order, and planning of the budget of medical facilities).

  13. 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…

  14. 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…

  15. 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…

  16. 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…

  17. 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;…

  18. 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)…

  19. 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…

  20. 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…

  1. 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…

  2. 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…

  3. 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)…

  4. 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…

  5. 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…

  6. 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…

  7. 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;…

  8. 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…

  9. 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)…

  10. 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…

  11. 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…

  12. QRS-fragmentation: Case report and review of the literature.

    PubMed

    Illescas-González, Edgar; Araiza-Garaygordobil, Diego; Sierra Lara, Jorge Daniel; Ramirez-Salazar, Aristoteles; Sierra-Fernández, Carlos; Alexanderson-Rosas, Erick

    2017-01-24

    Fragmentation of QRS complex (QRSf) is an easily evaluable, non-invasive electrocardiographic parameter that represents depolarization anomalies and that has been associated to several adverse outcomes such as sudden death, fibrosis, arrhythmic burden and worse prognosis in different conditions, including coronary artery disease (CAD). We present the case of a 69-year old male referred for study with symptoms of chronic stable angina. His electrocardiogram showed sinus rhythm, absence of Q waves, but the presence of QRSf in the inferior leads and V4-V6. A Tc-99 myocardial perfusion SPECT revealed a fixed perfusion defect in the inferolateral region, corresponding with the finding of QRSf. QRSf is a easily valuable electrocardiographic marker with relative sensitivity but poor specificity, whose routinary clinical application could contribute to rise the suspicion of coronary artery disease.

  13. 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

  14. 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.

  15. [Dynamics of the activity of cerebellar Purkinje cells induced by changes in the duration of complex spikes].

    PubMed

    Podladchikova, L N; Bondar', G G; Ivlev, S A; Tikidzhi-Khambur'ian, R A; Dunin-Barkovskiĭ, V L

    2008-01-01

    The relationship between complex and simple spikes of Purkinje cells from vermis cerebelli of guinea pigs has been investigated. The ratio of complex spikes innervated by the processes of one and the same liana-like fiber ("twins cells") has also been studied. Three types of complex spikes in each Purkinje cell from vermis cerebelli of guinea pigs (n = 44) have been differentiated, which differ in duration. It was found that long (10.28 +/- 0.27 ms) complex spikes in all cells lead to a more pronounced inhibition of simple spikes than complex spikes of short duration (6.08 +/- 0.25 ms). It was shown that the dynamics of duration of complex spikes coordinates with changes in the activity of some Purkinje cells and their local groups: (a) complex spikes generated before the onset of pauses of simple spikes are longer than complex spikes generated before the termination of pauses; (b) in "twins cells" innervated by one liana-like fiber, the properties of complex spikes change simultaneously; (c) The degree of synchronism of complex spikes in closely-spaced (to 150 microm) Purkinje cells receiving the inputs from different liana-like fibers increases with their duration. A possible functional role and the mechanisms of generation of complex spikes are discussed.

  16. 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.

  17. Circulating immune complexes and severe sepsis: duration of infection as the main determinant.

    PubMed Central

    Pocidalo, M A; Gibert, C; Verroust, P; Geniteau, M; Adam, C; Madec, Y; Gaudebout, C; Morel-Maroger, L

    1982-01-01

    The relation between the duration of bacterial infection and circulating immune complexes (CIC) level was evaluated using the C1q binding assay in a group of patients with well defined clinical sepsis. Fifty-four patients with endocarditis and 35 with post-open heart surgery mediastinitis were prospectively studied over a period of 2 years. CIC were detected in 42% of patients studied. Interindividual variations were observed but it was found that the level of CIC increased statistically with time (P less than 0.001). CIC were statistically linked with cryoglobulinemia (P less than 0.001), rheumatoid factor (P less than 0.001) and a decreased CH50 (P less than 0.05). CIC were more frequent in patients with endocarditis (53%) than in patients with mediastinitis (24%). However, when the duration of the infection was taken into account the difference was no longer significant. No relation could be evidenced between the incidence of CIC and clinical symptoms including prognosis and renal signs. In our experience, determination of CIC does not have a critical clinical value. PMID:7083630

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

    PubMed

    van Oosterom, Adriaan

    2014-01-01

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

  19. 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].

  20. A real time QRS detection using delay-coordinate mapping for the microcontroller implementation.

    PubMed

    Lee, Jeong-Whan; Kim, Kyeong-Seop; Lee, Bongsoo; Lee, Byungchae; Lee, Myoung-Ho

    2002-01-01

    In this article, we propose a new algorithm using the characteristics of reconstructed phase portraits by delay-coordinate mapping utilizing lag rotundity for a real-time detection of QRS complexes in ECG signals. In reconstructing phase portrait the mapping parameters, time delay, and mapping dimension play important roles in shaping of portraits drawn in a new dimensional space. Experimentally, the optimal mapping time delay for detection of QRS complexes turned out to be 20 ms. To explore the meaning of this time delay and the proper mapping dimension, we applied a fill factor, mutual information, and autocorrelation function algorithm that were generally used to analyze the chaotic characteristics of sampled signals. From these results, we could find the fact that the performance of our proposed algorithms relied mainly on the geometrical property such as an area of the reconstructed phase portrait. For the real application, we applied our algorithm for designing a small cardiac event recorder. This system was to record patients' ECG and R-R intervals for 1 h to investigate HRV characteristics of the patients who had vasovagal syncope symptom and for the evaluation, we implemented our algorithm in C language and applied to MIT/BIH arrhythmia database of 48 subjects. Our proposed algorithm achieved a 99.58% detection rate of QRS complexes.

  1. [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.

  2. Independent variable complexity for regional regression of the flow duration curve in ungauged basins

    NASA Astrophysics Data System (ADS)

    Fouad, Geoffrey; Skupin, André; Hope, Allen

    2016-04-01

    The flow duration curve (FDC) is one of the most widely used tools to quantify streamflow. Its percentile flows are often required for water resource applications, but these values must be predicted for ungauged basins with insufficient or no streamflow data. Regional regression is a commonly used approach for predicting percentile flows that involves identifying hydrologic regions and calibrating regression models to each region. The independent variables used to describe the physiographic and climatic setting of the basins are a critical component of regional regression, yet few studies have investigated their effect on resulting predictions. In this study, the complexity of the independent variables needed for regional regression is investigated. Different levels of variable complexity are applied for a regional regression consisting of 918 basins in the US. Both the hydrologic regions and regression models are determined according to the different sets of variables, and the accuracy of resulting predictions is assessed. The different sets of variables include (1) a simple set of three variables strongly tied to the FDC (mean annual precipitation, potential evapotranspiration, and baseflow index), (2) a traditional set of variables describing the average physiographic and climatic conditions of the basins, and (3) a more complex set of variables extending the traditional variables to include statistics describing the distribution of physiographic data and temporal components of climatic data. The latter set of variables is not typically used in regional regression, and is evaluated for its potential to predict percentile flows. The simplest set of only three variables performed similarly to the other more complex sets of variables. Traditional variables used to describe climate, topography, and soil offered little more to the predictions, and the experimental set of variables describing the distribution of basin data in more detail did not improve predictions

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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

  10. H558R polymorphism in SCN5A is associated with Keshan disease and QRS prolongation in Keshan disease patients.

    PubMed

    Jiang, S; Li, F L; Dong, Q; Liu, H W; Fang, C F; Shu, C; Cheng, H; Cui, J; Ma, H X; Chen, D Q; Li, H

    2014-08-28

    Keshan disease (KSD), a potentially fatal cardiomyopathy, has very high incidence in some selenium-poor regions of China. KSD may be accompanied with a variety of arrhythmia, which is associated with mutations in the gene coding for cardiac voltage-gated sodium channel (SCN5A). The molecular mechanism of KSD is still largely obscure. We aimed to determine the association between the H558R polymorphism of SCN5A and KSD. We recruited 71 patients with KSD and 80 geographical region-matched control subjects in our study. Vital sign and electrocardiographic (ECG) measurements were performed for heart rate, systolic pressure, diastolic pressure, PR interval, QT interval, QRS duration, ST-T changes and complete right bundle branch block (CRBBB), and H558R polymorphism was genotyped using the polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) method and sequencing. A significant association was found between the H558R polymorphism of exon 12 and KSD. Allele C carriers had a decreased risk for KSD with an odds ratio of 0.332 [95% confidence interval (CI), 0.160-0.692] as well as for QRS prolongation in KSD patients with an odds ratio of 0.089 (95%CI, 0.022-0.361). Our results provide support to the association between H558R polymorphism and the decreased risk for KSD. H558R polymorphism might increase susceptibility to KSD, and SCN5A containing the polymorphism might be a predisposing gene for QRS prolongation.

  11. 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)…

  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. 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;…

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

    PubMed

    Hulgard, Katrine; Ratcliffe, John M

    2016-02-09

    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.

  16. 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

  17. 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.

  18. Elicitation of the Acoustic Change Complex to Long-Duration Speech Stimuli in Four-Month-Old Infants

    PubMed Central

    Chen, Ke Heng; Small, Susan A.

    2015-01-01

    The acoustic change complex (ACC) is an auditory-evoked potential elicited to changes within an ongoing stimulus that indicates discrimination at the level of the auditory cortex. Only a few studies to date have attempted to record ACCs in young infants. The purpose of the present study was to investigate the elicitation of ACCs to long-duration speech stimuli in English-learning 4-month-old infants. ACCs were elicited to consonant contrasts made up of two concatenated speech tokens. The stimuli included native dental-dental /dada/ and dental-labial /daba/ contrasts and a nonnative Hindi dental-retroflex /daDa/ contrast. Each consonant-vowel speech token was 410 ms in duration. Slow cortical responses were recorded to the onset of the stimulus and to the acoustic change from /da/ to either /ba/ or /Da/ within the stimulus with significantly prolonged latencies compared with adults. ACCs were reliably elicited for all stimulus conditions with more robust morphology compared with our previous findings using stimuli that were shorter in duration. The P1 amplitudes elicited to the acoustic change in /daba/ and /daDa/ were significantly larger compared to /dada/ supporting that the brain discriminated between the speech tokens. These findings provide further evidence for the use of ACCs as an index of discrimination ability. PMID:26798343

  19. Elicitation of the Acoustic Change Complex to Long-Duration Speech Stimuli in Four-Month-Old Infants.

    PubMed

    Chen, Ke Heng; Small, Susan A

    2015-01-01

    The acoustic change complex (ACC) is an auditory-evoked potential elicited to changes within an ongoing stimulus that indicates discrimination at the level of the auditory cortex. Only a few studies to date have attempted to record ACCs in young infants. The purpose of the present study was to investigate the elicitation of ACCs to long-duration speech stimuli in English-learning 4-month-old infants. ACCs were elicited to consonant contrasts made up of two concatenated speech tokens. The stimuli included native dental-dental /dada/ and dental-labial /daba/ contrasts and a nonnative Hindi dental-retroflex /daDa/ contrast. Each consonant-vowel speech token was 410 ms in duration. Slow cortical responses were recorded to the onset of the stimulus and to the acoustic change from /da/ to either /ba/ or /Da/ within the stimulus with significantly prolonged latencies compared with adults. ACCs were reliably elicited for all stimulus conditions with more robust morphology compared with our previous findings using stimuli that were shorter in duration. The P1 amplitudes elicited to the acoustic change in /daba/ and /daDa/ were significantly larger compared to /dada/ supporting that the brain discriminated between the speech tokens. These findings provide further evidence for the use of ACCs as an index of discrimination ability.

  20. Nonsustained wide QRS tachycardia during an exercise ECG stress test.

    PubMed

    MacKenzie, Ross

    2007-01-01

    The evaluation of a nonsustained wide QRS tachycardia in a life insurance applicant's exercise test presents a special challenge to the medical director because of the unpredictable and potentially lethal nature of these arrhythmias. Ventricular tachycardia accounts for up to 80% of wide QRS tachycardias in unselected populations and more than 95% of cases with a prior myocardial infarction. Malignant ventricular arrhythmias usually occur in the presence of significant structural heart disease. In this setting, ventricular arrhythmias carry a high risk of sudden cardiac death. Less commonly, ventricular tachycardia occurs in hearts that appear normal. In many such cases, however, the heart is in fact not normal, but rather has less visible abnormalities including derangements of cardiac ion channels or structural proteins. In these individuals, ventricular arrhythmias also carry a high risk of sudden cardiac death. There are, however, some ventricular tachycardia syndromes which occur in normal hearts that have a more benign prognosis.

  1. Enhancement of accuracy and reproducibility of parametric modeling for estimating abnormal intra-QRS potentials in signal-averaged electrocardiograms.

    PubMed

    Lin, Chun-Cheng

    2008-09-01

    This work analyzes and attempts to enhance the accuracy and reproducibility of parametric modeling in the discrete cosine transform (DCT) domain for the estimation of abnormal intra-QRS potentials (AIQP) in signal-averaged electrocardiograms. One hundred sets of white noise with a flat frequency response were introduced to simulate the unpredictable, broadband AIQP when quantitatively analyzing estimation error. Further, a high-frequency AIQP parameter was defined to minimize estimation error caused by the overlap between normal QRS and AIQP in low-frequency DCT coefficients. Seventy-two patients from Taiwan were recruited for the study, comprising 30 patients with ventricular tachycardia (VT) and 42 without VT. Analytical results showed that VT patients had a significant decrease in the estimated AIQP. The global diagnostic performance (area under the receiver operating characteristic curve) of AIQP rose from 73.0% to 84.2% in lead Y, and from 58.3% to 79.1% in lead Z, when the high-frequency range fell from 100% to 80%. The combination of AIQP and ventricular late potentials further enhanced performance to 92.9% (specificity=90.5%, sensitivity=90%). Therefore, the significantly reduced AIQP in VT patients, possibly also including dominant unpredictable potentials within the normal QRS complex, may be new promising evidence of ventricular arrhythmias.

  2. Chromosome passenger complexes control anaphase duration and spindle elongation via a kinesin-5 brake

    PubMed Central

    Rozelle, Daniel K.; Hansen, Scott D.

    2011-01-01

    During mitosis, chromosome passenger complexes (CPCs) exhibit a well-conserved association with the anaphase spindle and have been implicated in spindle stability. However, their precise effect on the spindle is not clear. In this paper, we show, in budding yeast, that a CPC consisting of CBF3, Bir1, and Sli15, but not Ipl1, is required for normal spindle elongation. CPC mutants slow spindle elongation through the action of the bipolar kinesins Cin8 and Kip1. The same CPC mutants that slow spindle elongation also result in the enrichment of Cin8 and Kip1 at the spindle midzone. Together, these findings argue that CPCs function to organize the spindle midzone and potentially switch motors between force generators and molecular brakes. We also find that slowing spindle elongation delays the mitotic exit network (MEN)–dependent release of Cdc14, thus delaying spindle breakdown until a minimal spindle size is reached. We propose that these CPC- and MEN-dependent mechanisms are important for coordinating chromosome segregation with spindle breakdown and mitotic exit. PMID:21482719

  3. Comparison of the calculation QRS angle for bundle branch block detection

    NASA Astrophysics Data System (ADS)

    Goeirmanto, L.; Mengko, R.; Rajab, T. L.

    2016-04-01

    QRS angle represent condition of blood circulation in the heart. Normally QRS angle is between -30 until 90 degree. Left Axis Defiation (LAD) and Right Axis Defiation (RAD) are abnormality conditions that lead to Bundle Branch Block. QRS angle is calculated using common method from physicians and compared to mathematical method using difference amplitudos and difference areas. We analyzed the standard 12 lead electrocardiogram data from MITBIH physiobank database. All methods using lead I and lead avF produce similar QRS angle and right QRS axis quadrant. QRS angle from mathematical method using difference areas is close to common method from physician. Mathematical method using difference areas can be used as a trigger for detecting heart condition.

  4. 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.

  5. 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.

  6. Monitoring complex trace-gas mixtures by long-path laser absorption spectrometry. [in long duration manned mission closed environments

    NASA Technical Reports Server (NTRS)

    Green, B. D.; Steinfeld, J. I.

    1976-01-01

    Laser-based spectrophotometric methods, which have been proposed for the detection of trace concentrations of gaseous contaminants, include Raman and passive radiometry. The paper discusses a simple long-path laser absorption method which is capable of resolving complex mixtures of closely related trace contaminants at ppm levels. A number of species were selected which are most likely to accumulate in closed environments, such as submarines or long-duration manned space flights. Absorption coefficients at CO2 laser wavelengths were measured, accurate to + 3 per cent or better, for each of these species. This data base was then used to determine the presence and concentration of the contaminants in prepared mixtures of 12 to 15 gases. Computer programs have been developed which will permit a real-time analysis of the monitored atmosphere. Minimum detectable concentrations for individual species are generally in the ppm range, and are not seriously degraded by interferences even in complex mixtures. Estimates of the dynamic range of this monitoring technique for various system configurations and comparison with other methods of analysis are discussed

  7. [Long QRS tachycardia secondary to Aconitum napellus alkaloid ingestion].

    PubMed

    Gaibazzi, Nicola; Gelmini, Gian Paolo; Montresor, Graziano; Canel, Daniela; Comini, Teresa; Fracalossi, Claudio; Martinetti, Claudio; Poeta, Maria Luisa; Ziacchi, Vigilio

    2002-08-01

    The roots and seeds of the aconite (Aconitum napellus) contain alkaloids with modulatory activity on the sodium voltage-dependent channels; most fatal cases have been determined by ventricular tachycardia and respiratory paralysis. The only established treatment is supportive. We report a case of poisoning from Aconitum napellus, ingested by a husband and wife who thought the plant was "mountain chicory". They both had tachyarrhythmias, but the husband had more malignant episodes of hemodynamically unstable wide QRS tachycardia and respiratory paralysis requiring mechanical ventilation.

  8. 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

  9. 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…

  10. Real time electrocardiogram QRS detection using combined adaptive threshold

    PubMed Central

    Christov, Ivaylo I

    2004-01-01

    Background QRS and ventricular beat detection is a basic procedure for electrocardiogram (ECG) processing and analysis. Large variety of methods have been proposed and used, featuring high percentages of correct detection. Nevertheless, the problem remains open especially with respect to higher detection accuracy in noisy ECGs Methods A real-time detection method is proposed, based on comparison between absolute values of summed differentiated electrocardiograms of one of more ECG leads and adaptive threshold. The threshold combines three parameters: an adaptive slew-rate value, a second value which rises when high-frequency noise occurs, and a third one intended to avoid missing of low amplitude beats. Two algorithms were developed: Algorithm 1 detects at the current beat and Algorithm 2 has an RR interval analysis component in addition. The algorithms are self-adjusting to the thresholds and weighting constants, regardless of resolution and sampling frequency used. They operate with any number L of ECG leads, self-synchronize to QRS or beat slopes and adapt to beat-to-beat intervals. Results The algorithms were tested by an independent expert, thus excluding possible author's influence, using all 48 full-length ECG records of the MIT-BIH arrhythmia database. The results were: sensitivity Se = 99.69 % and specificity Sp = 99.65 % for Algorithm 1 and Se = 99.74 % and Sp = 99.65 % for Algorithm 2. Conclusion The statistical indices are higher than, or comparable to those, cited in the scientific literature. PMID:15333132

  11. A fast and accurate FPGA based QRS detection system.

    PubMed

    Shukla, Ashish; Macchiarulo, Luca

    2008-01-01

    An accurate Field Programmable Gate Array (FPGA) based ECG Analysis system is described in this paper. The design, based on a popular software based QRS detection algorithm, calculates the threshold value for the next peak detection cycle, from the median of eight previously detected peaks. The hardware design has accuracy in excess of 96% in detecting the beats correctly when tested with a subset of five 30 minute data records obtained from the MIT-BIH Arrhythmia database. The design, implemented using a proprietary design tool (System Generator), is an extension of our previous work and uses 76% resources available in a small-sized FPGA device (Xilinx Spartan xc3s500), has a higher detection accuracy as compared to our previous design and takes almost half the analysis time in comparison to software based approach.

  12. 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

  13. Re-entrant tachycardia using two bypass tracts and excluding AV node in short PR interval, normal QRS syndrome.

    PubMed Central

    Ward, D E; Camm, A J; Spurrell, R A

    1978-01-01

    In patients with the short PR interval, normal QRS complex syndrome, paroxysmal tachycardias are usually the result of circus movement involving the AV node and a partial or complete AV nodal bypass. We report 2 patients with this syndrome who suffered distressing rapid paroxysms of tachycardia but in whom there was evidence of a concealed direct VA connection. In both patients, tachycardia was initiated with critical AV prolongation distal to the His bundle, in response to programmed atrial premature stimuli. The constancy of the timing of the atrial echo from the onset of the QRS complex in the presence of a varying HV interval is evidence for involvement of the ventricles in the re-entry pathway. In addition, in both patients the appearance of left bundle-branch block during tachycardia was associated with appropriate prolongation of tachycardia cycle length consistent with the presence of a direct VA connection. The short AH interval during tachycardia and the absence of critical AH prolongation suggests the participation of a rapidly conducting pathway in the anterograde limb of the tachycardia circuit. PMID:708514

  14. ECG-derived spatial QRS-T angle is associated with ICD implantation, mortality and heart failure admissions in patients with LV systolic dysfunction

    PubMed Central

    Dugo, Clementina; Cave, Andrew; Zhou, Lifeng; Ayar, Zina; Christiansen, Jonathan; Scott, Tony; Dawson, Liane; Gavin, Andrew

    2017-01-01

    Background Increased spatial QRS-T angle has been shown to predict appropriate implantable cardioverter defibrilIator (ICD) therapy in patients with left ventricular systolic dysfunction (LVSD). We performed a retrospective cohort study in patients with left ventricular ejection fraction (LVEF) 31–40% to assess the relationship between the spatial QRS-T angle and other advanced ECG (A-ECG) as well as echocardiographic metadata, with all-cause mortality or ICD implantation for secondary prevention. Methods 534 patients ≤75 years of age with LVEF 31–40% were identified through an echocardiography reporting database. Digital 12-lead ECGs were retrospectively matched to 295 of these patients, for whom echocardiographic and A-ECG metadata were then generated. Data mining was applied to discover novel ECG and echocardiographic markers of risk. Machine learning was used to develop a model to predict possible outcomes. Results 49 patients (17%) had events, defined as either mortality (n = 16) or ICD implantation for secondary prevention (n = 33). 72 parameters (58 A-ECG, 14 echocardiographic) were univariately different (p<0.05) in those with vs. without events. After adjustment for multiplicity, 24 A-ECG parameters and 3 echocardiographic parameters remained different (p<2x10-3). These included the posterior-to-leftward QRS loop ratio from the derived vectorcardiographic horizontal plane (previously associated with pulmonary artery pressure, p = 2x10-6); spatial mean QRS-T angle (134 vs. 112°, p = 1.6x10-4); various repolarisation vectors; and a previously described 5-parameter A-ECG score for LVSD (p = 4x10-6) that also correlated with echocardiographic global longitudinal strain (R2 = - 0.51, P < 0.0001). A spatial QRS-T angle >110° had an adjusted HR of 3.4 (95% CI 1.6 to 7.4) for secondary ICD implantation or all-cause death and adjusted HR of 4.1 (95% CI 1.2 to 13.9) for future heart failure admission. There was a loss of complexity between A-ECG and

  15. QRS voltage of the electrocardiogram and Frank vectorcardiogram in relation to ventricular volume.

    PubMed Central

    Talbot, S; Kilpatrick, D; Jonathan, A; Raphael, M J

    1977-01-01

    Left ventricular volumes were estimated in 59 patients, who were investigated by single plane ventriculography and coronary arteriography. The relation of the left ventricular end-diastolic volumes to the QRS voltage of the 12-lead electrocardiograms and Frank vectorcardiograms was examined. It was found that the maximum spatial QRS voltage and the R wave voltage of leads V5 and V6 in patients without left ventricular hypertrophy were inversely correlated with end-diastolic volume. This inverse relation of QRS voltage and left ventricular volume may explain loss of QRS voltage with dilatation of the heart. In patients with left ventricular hypertropy QRS voltage is usually positively correlated with the degree of hypertrophy, but there is no significant correlation in the presence of cardiac dilatation. If the results of this study are extrapolated to patients with left ventricular hypertrophy and cardiac dilatation, then the inverse correlation of volume and QRS voltage may reduce the diagnostic sensitivity of unipolar chest lead and vectorcardiographic criteria of left ventricular hypertrophy. PMID:143949

  16. 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.

  17. 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.

  18. 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…

  19. Ebstein anomaly in an adult presenting with wide QRS tachycardia: diagnostic and therapeutic dilemmas.

    PubMed

    Rao, Mamatha Punjee Raja; Panduranga, Prashanth; Al-Mukhaini, Mohammed; Al-Jufaili, Mahmood

    2012-06-01

    A 51-year-old man presented to the emergency department with sustained hemodynamically unstable wide QRS tachycardia and was revived successfully by immediate direct current (DC) cardioversion. There was evidence of previous open heart surgery, possibly atrial septal defect closure. Transthoracic echocardiography showed severe Ebstein anomaly with severe tricuspid regurgitation, no residual atrial septal defect, but with severe right ventricular dysfunction. Subsequent electrocardiograms showed transient atrial fibrillation with no manifest Wolff-Parkinson-White (WPW) accessory pathway during sinus rhythm. The cause of wide QRS tachycardia in this patient may be WPW related or ventricular tachycardia. This case illustrates the diagnostic and therapeutic dilemmas in patients with wide QRS tachycardia and suspected WPW syndrome. In addition, this case demonstrates that unoperated Ebstein anomaly can present in late adult life with tachyarrhythmias.

  20. Online digital filter and QRS detector applicable in low resource ECG monitoring systems.

    PubMed

    Tabakov, Serafim; Iliev, Ivo; Krasteva, Vessela

    2008-11-01

    The present work describes fast computation methods for real-time digital filtration and QRS detection, both applicable in autonomous personal ECG systems for long-term monitoring. Since such devices work under considerable artifacts of intensive body and electrode movements, the input filtering should provide high-quality ECG signals supporting the accurate ECG interpretation. In this respect, we propose a combined high-pass and power-line interference rejection filter, introducing the simple principle of averaging of samples with a predefined distance between them. In our implementation (sampling frequency of 250 Hz), we applied averaging over 17 samples distanced by 10 samples (Filter10x17), thus realizing a comb filter with a zero at 50 Hz and high-pass cut-off at 1.1 Hz. Filter10x17 affords very fast filtering procedure at the price of minimal computing resources. Another benefit concerns the small ECG distortions introduced by the filter, providing its powerful application in the preprocessing module of diagnostic systems analyzing the ECG morphology. Filter10x17 does not attenuate the QRS amplitude, or introduce significant ST-segment elevation/depression. The filter output produces a constant error, leading to uniform shifting of the entire P-QRS-T segment toward about 5% of the R-peak amplitude. Tests with standardized ECG signals proved that Filter10x17 is capable to remove very strong baseline wanderings, and to fully suppress 50 Hz interferences. By changing the number of the averaged samples and the distance between them, a filter design with different cut-off and zero frequency could be easily achieved. The real-time QRS detector is designed with simplified computations over single channel, low-resolution ECGs. It relies on simple evaluations of amplitudes and slopes, including history of their mean values estimated over the preceding beats, smart adjustable thresholds, as well as linear logical rules for identification of the R-peaks in real

  1. A narrow QRS tachycardia and cannon A waves: What is the mechanism?

    PubMed

    Ali, Hussam; Epicoco, Gianluca; De Ambroggi, Guido; Lupo, Pierpaolo; Foresti, Sara; Cappato, Riccardo

    2016-12-23

    Regular narrow QRS tachycardia, particularly if well-tolerated, is usually considered a "benign" arrhythmia of a supraventricular origin. This case concerns an 82-year-old male with ischemic heart disease who presented with recurrent episodes of a narrow QRS tachycardia that was initially diagnosed and treated as atrial tachyarrhythmia. However, careful physical examination and ECG analysis established the correct diagnosis, and the patient was managed appropriately. Remarkably, the observation of irregular cannon A waves, and Lewis lead recording, confirmed atrioventricular dissociation during tachycardia and indicated its underlying mechanism.

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

    PubMed

    Karimipour, Atiyeh; Homaeinezhad, Mohammad Reza

    2014-09-01

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

  3. 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

  4. Large-scale pharmacogenomic study of sulfonylureas and the QT, JT and QRS intervals: CHARGE Pharmacogenomics Working Group.

    PubMed

    Floyd, J S; Sitlani, C M; Avery, C L; Noordam, R; Li, X; Smith, A V; Gogarten, S M; Li, J; Broer, L; Evans, D S; Trompet, S; Brody, J A; Stewart, J D; Eicher, J D; Seyerle, A A; Roach, J; Lange, L A; Lin, H J; Kors, J A; Harris, T B; Li-Gao, R; Sattar, N; Cummings, S R; Wiggins, K L; Napier, M D; Stürmer, T; Bis, J C; Kerr, K F; Uitterlinden, A G; Taylor, K D; Stott, D J; de Mutsert, R; Launer, L J; Busch, E L; Méndez-Giráldez, R; Sotoodehnia, N; Soliman, E Z; Li, Y; Duan, Q; Rosendaal, F R; Slagboom, P E; Wilhelmsen, K C; Reiner, A P; Chen, Y-DI; Heckbert, S R; Kaplan, R C; Rice, K M; Jukema, J W; Johnson, A D; Liu, Y; Mook-Kanamori, D O; Gudnason, V; Wilson, J G; Rotter, J I; Laurie, C C; Psaty, B M; Whitsel, E A; Cupples, L A; Stricker, B H

    2016-12-13

    Sulfonylureas, a commonly used class of medication used to treat type 2 diabetes, have been associated with an increased risk of cardiovascular disease. Their effects on QT interval duration and related electrocardiographic phenotypes are potential mechanisms for this adverse effect. In 11 ethnically diverse cohorts that included 71 857 European, African-American and Hispanic/Latino ancestry individuals with repeated measures of medication use and electrocardiogram (ECG) measurements, we conducted a pharmacogenomic genome-wide association study of sulfonylurea use and three ECG phenotypes: QT, JT and QRS intervals. In ancestry-specific meta-analyses, eight novel pharmacogenomic loci met the threshold for genome-wide significance (P<5 × 10(-8)), and a pharmacokinetic variant in CYP2C9 (rs1057910) that has been associated with sulfonylurea-related treatment effects and other adverse drug reactions in previous studies was replicated. Additional research is needed to replicate the novel findings and to understand their biological basis.The Pharmacogenomics Journal advance online publication, 13 December 2016; doi:10.1038/tpj.2016.90.

  5. 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

  6. Research on electrocardiogram baseline wandering correction based on wavelet transform, QRS barycenter fitting, and regional method.

    PubMed

    Song, Jinzhong; Yan, Hong; Li, Yanjun; Mu, Kaiyu

    2010-09-01

    Baseline wandering in electrocardiogram (ECG) is one of the biggest interferences in visualization and computerized detection of waveforms (especially ST-segment) based on threshold decision. A new method based on wavelet transform, QRS barycenter fitting and regional method was proposed in this paper. Firstly, wavelet transform as a coarse correction was used to remove the baseline wandering, whose frequency bands were non-overlapping with that of ST-segment. Secondly, QRS barycenter fitting was applied as a detailed correction. The third, the regional method was used to transfer baseline to zero. Finally, the method in this paper was proved to perform better than filtering and function fitting methods in baseline wandering correction after the long-term ST database (LTST) verification. In addition, the proposed method is simple and easy to carry out, and in current use.

  7. Delineation of QRS offset by instantaneous changes in ECG vector angle can improve detection of acute inferior myocardial infarctions.

    PubMed

    Starc, Vito; Schlegel, Todd T

    2016-01-01

    We developed an automated new method for determining QRS offset, based on angular velocity (AV) changes around the QRS loop, and compared the method's performance to that of manual and more established automated methods for determining QRS offset in both healthy subjects and patients with acute myocardial infarction (AMI). Specifically, using Frank leads reconstructed from standard 12-lead ECGs, we determined AV in the direction of change raised to the 4th power, d(t). We found that the d(t)-determined AV transition (ΔAV) nearly coincided with manually determined QRS offset in healthy subjects, and in 27 patients with anterior AMI. However, in 31 patients with inferior AMI, ΔAV typically preceded that of QRS offset determined by the established automated methods, and by more than 10ms in 32% of cases. While this "ΔAV precedence" coincided with diagnostic ST elevation in only a minority of patients with recent inferior AMI, the use of ΔAV precedence as a complement to traditional determination of ST elevation increased the sensitivity for detecting inferior AMIs from 23 to 42%.

  8. Reversal of Pacing-Induced Cardiomyopathy by Normal QRS Axis Pacing

    PubMed Central

    Yang, Ji Hyun; Kim, Ju Youn; Kim, Sung-Hwan

    2016-01-01

    Right ventricular apical pacing has been a commonly used method for placement of permanent pacemaker, but it is known to be associated with ventricular dyssynchrony and may lead to heart failure. Septal pacing could be an alternative method to improve this complication but the results have been conflicting; hence, other strategies are needed. This case is about a patient with pacing-induced cardiomyopathy who showed much improvement after repositioning the leads to a site different from that of normally paced QRS axis. PMID:27275181

  9. Automatic Real-Time Embedded QRS Complex Detection for a Novel Patch-Type Electrocardiogram Recorder

    PubMed Central

    Tanev, George; Flintrup, Morten; Osmanagic, Armin; Egstrup, Kenneth; Hoppe, Karsten; Jennum, Poul; Jeppesen, Jørgen L.; Iversen, Helle K.; Sorensen, Helge B. D.

    2015-01-01

    Cardiovascular diseases are projected to remain the single leading cause of death globally. Timely diagnosis and treatment of these diseases are crucial to prevent death and dangerous complications. One of the important tools in early diagnosis of arrhythmias is analysis of electrocardiograms (ECGs) obtained from ambulatory long-term recordings. The design of novel patch-type ECG recorders has increased the accessibility of these long-term recordings. In many applications, it is furthermore an advantage for these devices that the recorded ECGs can be analyzed automatically in real time. The purpose of this study was therefore to design a novel algorithm for automatic heart beat detection, and embed the algorithm in the CE marked ePatch heart monitor. The algorithm is based on a novel cascade of computationally efficient filters, optimized adaptive thresholding, and a refined search back mechanism. The design and optimization of the algorithm was performed on two different databases: The MIT-BIH arrhythmia database (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$Se=99.90$ \\end{document}%, \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$P^{+}=99.87$ \\end{document}) and a private ePatch training database (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$Se=99.88$ \\end{document}%, \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$P^{+}=99.37$ \\end{document}%). The offline validation was conducted on the European ST-T database (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$Se=99.84$ \\end{document}%, \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$P^{+}=99.71$ \\end{document}%). Finally, a double-blinded validation of the embedded algorithm was conducted on a private ePatch validation database (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$Se=99.91$ \\end{document}%, \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$P^{+}=99.79$ \\end{document}%). The algorithm was thus validated with high clinical performance on more than 300 ECG records from 189 different subjects with a high number of different abnormal beat morphologies. This demonstrates the strengths of the algorithm, and the potential for this embedded algorithm to improve the possibilities of early diagnosis and treatment of cardiovascular diseases. PMID:27170891

  10. Automatic Real-Time Embedded QRS Complex Detection for a Novel Patch-Type Electrocardiogram Recorder.

    PubMed

    Saadi, Dorthe B; Tanev, George; Flintrup, Morten; Osmanagic, Armin; Egstrup, Kenneth; Hoppe, Karsten; Jennum, Poul; Jeppesen, Jørgen L; Iversen, Helle K; Sorensen, Helge B D

    2015-01-01

    Cardiovascular diseases are projected to remain the single leading cause of death globally. Timely diagnosis and treatment of these diseases are crucial to prevent death and dangerous complications. One of the important tools in early diagnosis of arrhythmias is analysis of electrocardiograms (ECGs) obtained from ambulatory long-term recordings. The design of novel patch-type ECG recorders has increased the accessibility of these long-term recordings. In many applications, it is furthermore an advantage for these devices that the recorded ECGs can be analyzed automatically in real time. The purpose of this study was therefore to design a novel algorithm for automatic heart beat detection, and embed the algorithm in the CE marked ePatch heart monitor. The algorithm is based on a novel cascade of computationally efficient filters, optimized adaptive thresholding, and a refined search back mechanism. The design and optimization of the algorithm was performed on two different databases: The MIT-BIH arrhythmia database ([Formula: see text]%, [Formula: see text]) and a private ePatch training database ([Formula: see text]%, [Formula: see text]%). The offline validation was conducted on the European ST-T database ([Formula: see text]%, [Formula: see text]%). Finally, a double-blinded validation of the embedded algorithm was conducted on a private ePatch validation database ([Formula: see text]%, [Formula: see text]%). The algorithm was thus validated with high clinical performance on more than 300 ECG records from 189 different subjects with a high number of different abnormal beat morphologies. This demonstrates the strengths of the algorithm, and the potential for this embedded algorithm to improve the possibilities of early diagnosis and treatment of cardiovascular diseases.

  11. A robust physiology-based source separation method for QRS detection in low amplitude fetal ECG recordings.

    PubMed

    Vullings, R; Peters, C H L; Hermans, M J M; Wijn, P F F; Oei, S G; Bergmans, J W M

    2010-07-01

    The use of the non-invasively obtained fetal electrocardiogram (ECG) in fetal monitoring is complicated by the low signal-to-noise ratio (SNR) of ECG signals. Even after removal of the predominant interference (i.e. the maternal ECG), the SNR is generally too low for medical diagnostics, and hence additional signal processing is still required. To this end, several methods for exploiting the spatial correlation of multi-channel fetal ECG recordings from the maternal abdomen have been proposed in the literature, of which principal component analysis (PCA) and independent component analysis (ICA) are the most prominent. Both PCA and ICA, however, suffer from the drawback that they are blind source separation (BSS) techniques and as such suboptimum in that they do not consider a priori knowledge on the abdominal electrode configuration and fetal heart activity. In this paper we propose a source separation technique that is based on the physiology of the fetal heart and on the knowledge of the electrode configuration. This technique operates by calculating the spatial fetal vectorcardiogram (VCG) and approximating the VCG for several overlayed heartbeats by an ellipse. By subsequently projecting the VCG onto the long axis of this ellipse, a source signal of the fetal ECG can be obtained. To evaluate the developed technique, its performance is compared to that of both PCA and ICA and to that of augmented versions of these techniques (aPCA and aICA; PCA and ICA applied on preprocessed signals) in generating a fetal ECG source signal with enhanced SNR that can be used to detect fetal QRS complexes. The evaluation shows that the developed source separation technique performs slightly better than aPCA and aICA and outperforms PCA and ICA and has the main advantage that, with respect to aPCA/PCA and aICA/ICA, it performs more robustly. This advantage renders it favorable for employment in automated, real-time fetal monitoring applications.

  12. 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.

  13. 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.

  14. Role of common and rare variants in SCN10A: results from the Brugada syndrome QRS locus gene discovery collaborative study

    PubMed Central

    Behr, Elijah R.; Savio-Galimberti, Eleonora; Barc, Julien; Holst, Anders G.; Petropoulou, Evmorfia; Prins, Bram P.; Jabbari, Javad; Torchio, Margherita; Berthet, Myriam; Mizusawa, Yuka; Yang, Tao; Nannenberg, Eline A.; Dagradi, Federica; Weeke, Peter; Bastiaenan, Rachel; Ackerman, Michael J.; Haunso, Stig; Leenhardt, Antoine; Kääb, Stefan; Probst, Vincent; Redon, Richard; Sharma, Sanjay; Wilde, Arthur; Tfelt-Hansen, Jacob; Schwartz, Peter; Roden, Dan M.; Bezzina, Connie R.; Olesen, Morten; Darbar, Dawood; Guicheney, Pascale; Crotti, Lia; Jamshidi, Yalda

    2015-01-01

    Aims Brugada syndrome (BrS) remains genetically heterogeneous and is associated with slowed cardiac conduction. We aimed to identify genetic variation in BrS cases at loci associated with QRS duration. Methods and results A multi-centre study sequenced seven candidate genes (SCN10A, HAND1, PLN, CASQ2, TKT, TBX3, and TBX5) in 156 Caucasian SCN5A mutation-negative BrS patients (80% male; mean age 48) with symptoms (64%) and/or a family history of sudden death (47%) or BrS (18%). Forty-nine variants were identified: 18 were rare (MAF <1%) and non-synonymous; and 11/18 (61.1%), mostly in SCN10A, were predicted as pathogenic using multiple bioinformatics tools. Allele frequencies were compared with the Exome Sequencing and UK10K Projects. SKAT methods tested rare variation in SCN10A finding no statistically significant difference between cases and controls. Co-segregation analysis was possible for four of seven probands carrying a novel pathogenic variant. Only one pedigree (I671V/G1299A in SCN10A) showed co-segregation. The SCN10A SNP V1073 was, however, associated strongly with BrS [66.9 vs. 40.1% (UK10K) OR (95% CI) = 3.02 (2.35–3.87), P = 8.07 × 10–19]. Voltage-clamp experiments for NaV1.8 were performed for SCN10A common variants V1073, A1073, and rare variants of interest: A200V and I671V. V1073, A200V and I671V, demonstrated significant reductions in peak INa compared with ancestral allele A1073 (rs6795970). Conclusion Rare variants in the screened QRS-associated genes (including SCN10A) are not responsible for a significant proportion of SCN5A mutation negative BrS. The common SNP SCN10A V1073 was strongly associated with BrS and demonstrated loss of NaV1.8 function, as did rare variants in isolated patients. PMID:25691538

  15. Atrial fibrillation with wide QRS tachycardia and undiagnosed Wolff-Parkinson-White syndrome: diagnostic and therapeutic dilemmas in a pediatric patient.

    PubMed

    Panduranga, Prashanth; Al-Farqani, Abdullah; Al-Rawahi, Najib

    2012-11-01

    A 10-year-old girl presented to the emergency department of a regional hospital with 1 episode of generalized tonic-clonic seizures. Postictal monitoring followed by a 12-lead electrocardiogram showed fast atrial fibrillation with intermittent wide QRS regular tachycardia. Immediately following this, her rhythm changed to wide QRS irregular tachycardia without hemodynamic compromise. She was suspected to have ventricular tachycardia and was treated with intravenous amiodarone with cardioversion to sinus rhythm. Subsequent electrocardiogram in sinus rhythm showed typical features of manifest Wolff-Parkinson-White (WPW) accessory pathway. This case illustrates the diagnostic and therapeutic dilemmas in patients with atrial fibrillation, wide QRS tachycardia, and undiagnosed WPW syndrome with antidromic conduction of atrial arrhythmias through the accessory pathway. Furthermore, this case demonstrates that undiagnosed wide QRS tachycardias need to be treated with drugs acting on the accessory pathway, thus keeping in mind underlying WPW syndrome as a possibility to avoid potentially catastrophic events.

  16. 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

  17. Prognostic Implication of the QRS Axis and its Association with Myocardial Scarring in Patients with Left Bundle Branch Block

    PubMed Central

    Park, Chan Soon; Cha, Myung-jin; Choi, Eue-Keun

    2017-01-01

    Background and Objectives Left bundle branch block (LBBB) with left axis deviation (LAD) has a worse prognosis than LBBB with a normal axis, and myocardial dysfunction has been suggested as a cause of left axis deviation. This study investigated the prognostic significance of the QRS axis in patients with LBBB and analyzed its relationship with the amount of myocardial scarring. Subjects and Methods A total of 829 patients were diagnosed with LBBB at Seoul National University Hospital from October 2004 to June 2014. Of these, 314 who were asymptomatic and had no previous history of cardiac disease were included in the present study. Myocardial scarring was calculated using the Selvester QRS scoring system, and LAD was defined as a QRS axis between -180° and -30°. Results Of the total patients, 91 (29%) had LAD, and patients were followed for a median of 30 months. During follow-up, two patients were hospitalized for de novo heart failure, four had pacemaker implants, and 10 died. There was a significant inverse correlation between myocardial scar score and the QRS axis (r=-0.356, p<0.001). Patients with concomitant LAD had a higher rate of major cardiac adverse events compared with patients with a normal axis (5.5% vs. 1.3%, log-rank p=0.010); the prognostic value was attenuated in multivariable analysis (hazard ratio 4.117; 95% confidence interval 0.955-17.743; p=0.058). Conclusion Concomitant LAD is an indicator of poor prognosis for patients with LBBB and may be associated with greater myocardial scarring. PMID:28382083

  18. 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.

  19. 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

  20. Usefulness of the QRS-T angle to improve long-term risk stratification of patients with acute myocardial infarction and depressed left ventricular ejection fraction.

    PubMed

    Raposeiras-Roubín, Sergio; Virgós-Lamela, Alejandro; Bouzas-Cruz, Noelia; López-López, Andrea; Castiñeira-Busto, María; Fernández-Garda, Rita; García-Castelo, Alberto; Rodríguez-Mañero, Moisés; García-Acuña, José María; Abu-Assi, Emad; González-Juanatey, José Ramón

    2014-04-15

    In light of the low cost, the widespread availability of the electrocardiogram, and the increasing economic burden of the health-related problems, we aimed to analyze the prognostic value of automatic frontal QRS-T angle to predict mortality in patients with left ventricular (LV) systolic dysfunction after acute myocardial infarction (AMI). About 467 consecutive patients discharged with diagnosis of AMI and with LV ejection fraction ≤40% were followed during 3.9 years (2.1 to 5.9). From them, 217 patients (47.5%) died. The frontal QRS-T angle was higher in patients who died (116.6±52.8 vs 77.9±55.1, respectively, p<0.001). The QRS-T angle value of 90° was the most accurate to predict all-cause cardiac death. After multivariate analysis, frontal QRS-T angle remained as an excellent predictor of all-cause and cardiac deaths, increasing the mortality 6% per each 10°. For the global mortality, the hazard ratio for a QRS-T angle>90° was 2.180 (1.558 to 3.050), and for the combined end point of cardiac death and appropriate implantable cardioverter defribrillator therapy, it was 2.385 (1.570 to 3.623). This independent predictive value was maintained even after adjusting by bundle brunch block, ST-elevation AMI, and its localization. In conclusion, a wide automatic frontal QRS-T angle (>90°) is a good discriminator of long-term mortality in patients with LV systolic dysfunction after an AMI. The ability to easily measure it from a standard 12-lead electrocardiogram together with its prognostic value makes the frontal QRS-T angle an attractive tool to help clinicians to improve risk stratification of those patients.

  1. Prognostic Value of Frontal QRS-T Angle in Patients without Clinical Evidence of Cardiovascular Disease (From the Multi-Ethnic Study of Atherosclerosis [MESA])

    PubMed Central

    Walsh, Joseph A; Soliman, Elsayed Z.; Ilkhanoff, Leonard; Ning, Hongyan; Liu, Kiang; Nazarian, Saman; Lloyd-Jones, Donald M.

    2013-01-01

    Abnormal frontal QRS-T angle on a 12 lead electrocardiogram (ECG) is associated with incident coronary heart disease and total mortality in a biracial cohort but there have been no studies to date examining QRS-T angle’s prognostic value across multiple ethnicities. We studied 6,814 participants (52.7% women, mean age 62) from MESA; a multi-ethnic cohort aged 45–84 free of clinical cardiovascular disease (CVD) at enrollment. Baseline examination included measurement of traditional risk factors and 12-lead ECG’s. Frontal QRS-T axis was defined as normal (<75th percentile), borderline (75–95th percentile) or abnormal (≥ 95th percentile) and participants were followed for the composite endpoint of incident CVD events: cardiovascular death, myocardial infarction, angina pectoris or heart failure. After 7.6 years of follow up there were 444 total events. Borderline ((HR 1.37 95% Confidence Interval (CI) (1.10,1.70)) and abnormal QRS-T angle (HR 2.2 95% CI (1.63, 2.97)) was associated with incident CVD events in multivariable-adjusted models. However, after adjusting for T wave abnormalities there was no statistically significant association of either borderline (HR 1.12 95% CI (0.90, 1.41)) or abnormal (HR 1.31 95% CI (0.93, 1.84)) QRS-T angle with incident CVD events. Abnormal frontal QRS-T angle predicts incident CVD events in a multiethnic population and this increased risk is primarily mediated through T wave abnormalities. QRS-T angle provides an easily interpretable, continuous marker of abnormal ventricular repolarization that can aid the everyday clinician in risk prediction. PMID:24063831

  2. [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.

  3. Diagnostic dilemma with a narrow QRS regular rhythm at normal rates in a patient with corrected transposition of great arteries

    PubMed Central

    Shenthar, Jayaprakash; Rai, Maneesh K.

    2015-01-01

    A 35 year old male, known case of corrected transposition of great arteries presented with exertional dyspnea and recurrent pre-syncope. 12 lead electrocardiogram revealed a regular rhythm at 75 beats per minute, P waves occurring on the upstroke of T waves and apparent 1:1 P-QRS relationship. The possibilities to be considered – complete AV block with junctional escape, junctional rhythm with 1:1 retrograde conduction, junctional rhythm with isorhythmic AV dissociation and prolonged PR interval have been discussed. PMID:26937115

  4. Wide QRS in a 2-month infant associated with recurrent ventricular tachycardia: A case of Brugada-like syndrome.

    PubMed

    Jomaa, W; Selmi, W; Hamdi, S; Azaiez, M A; El Hraiech, A; Ben Hamda, K; Maatouk, F

    2017-02-01

    We report the case of a 2-month old infant who experienced recurrent sustained ventricular tachycardia (VT) in a structurally normal heart. Resting electrocardiogram (ECG) showed wide QRS with a complete right bundle branch bloc (RBBB) morphology. There was no family history of syncope or sudden death, but the ECGs of the father and the brother showed incomplete RBBB with negative T waves on V1 lead. This case seems to fit well with the newly defined entity of Brugada-like syndrome with a highly suspected genetic underlying disposition.

  5. 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

  6. Flow-duration curves

    USGS Publications Warehouse

    Searcy, James Kincheon

    1959-01-01

    The flow-duration curve is a cumulative frequency curve that shows the percent of time specified discharges were equaled or exceeded during a given period. It combines in one curve the flow characteristics of a stream throughout the range of discharge, without regard to the sequence of occurrence. If the period upon which the curve is based represents the long-term flow of a stream, the curve may be used to predict the distribution of future flows for water- power, water-supply, and pollution studies. This report shows that differences in geology affect the low-flow ends of flow-duration curves of streams in adjacent basins. Thus, duration curves are useful in appraising the geologic characteristics of drainage basins. A method for adjusting flow-duration curves of short periods to represent long-term conditions is presented. The adjustment is made by correlating the records of a short-term station with those of a long-term station.

  7. Impacts of coulomb interactions on the magnetic responses of excitonic complexes in single semiconductor nanostructures.

    PubMed

    Chang, Wen-Hao; Lin, Chia-Hsien; Fu, Ying-Jhe; Lin, Ta-Chun; Lin, Hsuan; Cheng, Shuen-Jen; Lin, Sheng-Di; Lee, Chien-Ping

    2010-01-21

    We report on the diamagnetic responses of different exciton complexes in single InAs/GaAs self-assembled quantum dots (QDs) and quantum rings (QRs). For QDs, the imbalanced magnetic responses of inter-particle Coulomb interactions play a crucial role in the diamagnetic shifts of excitons (X), biexcitons (XX), and positive trions (X-). For negative trions (X-) in QDs, anomalous magnetic responses are observed, which cannot be described by the conventional quadratic energy shift with the magnetic field. The anomalous behavior is attributed to the apparent change in the electron wave function extent after photon emission due to the strong Coulomb attraction by the hole in its initial state. In QRs, the diamagnetic responses of X and XX also show different behaviors. Unlike QDs, the diamagnetic shift of XX in QRs is considerably larger than that of X. The inherent structural asymmetry combined with the inter-particle Coulomb interactions makes the wave function distribution of XX very different from that of X in QRs. Our results suggest that the phase coherence of XX in QRs may survive from the wave function localization due to the structural asymmetry or imperfections.

  8. Complexity.

    PubMed

    Gómez-Hernández, J Jaime

    2006-01-01

    It is difficult to define complexity in modeling. Complexity is often associated with uncertainty since modeling uncertainty is an intrinsically difficult task. However, modeling uncertainty does not require, necessarily, complex models, in the sense of a model requiring an unmanageable number of degrees of freedom to characterize the aquifer. The relationship between complexity, uncertainty, heterogeneity, and stochastic modeling is not simple. Aquifer models should be able to quantify the uncertainty of their predictions, which can be done using stochastic models that produce heterogeneous realizations of aquifer parameters. This is the type of complexity addressed in this article.

  9. Effects of resting ischemia assessed by thallium scintigraphy on QRS scoring system for estimating left ventricular function quantified by radionuclide angiography in acute myocardial infarction patients.

    PubMed

    DePace, N L; Hakki, A H; Iskandrian, A S

    1984-06-01

    The purpose of this study was to determine whether resting ischemia limits the usefulness of the QRS scoring system in predicting left ventricular (LV) ejection fraction (EF) in patients with acute infarction. We studied 48 patients after acute infarction by means of 12-lead ECG, thallium-201 scintigraphy, and radionuclide angiography. The thallium-201 scintigrams showed fixed defects in 25 patients, perfusion defects with partial or complete redistribution in the delayed images in 19 patients, and normal images in the remaining four patients. In the 48 patients there was a significant correlation between the QRS score and LVEF (r = -0.67; p less than 0.001). Patients with fixed defects showed a better correlation than patients with resting ischemia (r = -0.77 vs r = -0.60). A QRS score of 3 or less was used to separate patients with LVEF of 40% or greater from those with lower LVEF in patients with fixed defects (p = 0.0005), but this cutoff did not categorize patients with resting ischemia as to LVEF. Thus the presence of rest ischemia in patients with acute infarction may affect the correlation between QRS score and LVEF.

  10. The value of the QRS scoring system in assessing regional and global left ventricular ejection fraction early after myocardial infarction.

    PubMed

    Bergovec, M; Prpìć, H; Mihatov, S; Zigman, M; Vukosavić, D; Birtić, K; Franceschi, D; Barić, L

    1993-08-01

    In 71 patients with a myocardial infarction (MI) (anterior in 27, inferior in 44 patients) global (GEF) and regional (REF) left ventricular ejection fractions were determined by radionuclide ventriculography and estimated from a 12 lead electrocardiogram (ECG), using Selvester's QRS score, during the early phase of a MI (15 to 21 days following MI). Global ejection fractions determined by radionuclide ventriculography and from ECG using Palmeri's method were: for all MI 40.8 +/- 12.6% vs 39.6 +/- 11.4%; in the group of anterior MI 32.0 +/- 10.0% vs 30.0 +/- 9.7% and in the group of inferior MI 48.9 +/- 12.0% vs 45.1 +/- 8.2%. A good correlation was found between global ejection fractions determined by radionuclide ventriculography and ECG, as well as between radionuclide GEF and ECG score. A weaker correlation was found between radionuclide GEF and enzymes among all MIs and in the group of anterior MI, while in the group of inferior MI this correlation was insignificant. The analysis of REF determined by radionuclide ventriculography and ECG showed the greatest abnormalities in the infarct region, but in the group of anterior MI, dysfunction was present in the whole left ventricle. The comparison of infarct-related REF derived from radionuclide ventriculography, with the QRS score showed a significantly higher correlation than the comparison with enzymes. ECG estimation of REF from a modified Palmeri's equation showed a better correlation with radionuclide REF than did GEF derived from the standard Palmeri's equation: anterior MI; r = 0.90 vs r = 0.82, inferior MI; r = 0.84 vs r = 0.69, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Long duration flights management

    NASA Astrophysics Data System (ADS)

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

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

  12. Impact of response duration on multisensory integration.

    PubMed

    Ghose, Dipanwita; Barnett, Zachary P; Wallace, Mark T

    2012-11-01

    Multisensory neurons in the superior colliculus (SC) have been shown to have large receptive fields that are heterogeneous in nature. These neurons have the capacity to integrate their different sensory inputs, a process that has been shown to depend on the physical characteristics of the stimuli that are combined (i.e., spatial and temporal relationship and relative effectiveness). Recent work has highlighted the interdependence of these factors in driving multisensory integration, adding a layer of complexity to our understanding of multisensory processes. In the present study our goal was to add to this understanding by characterizing how stimulus location impacts the temporal dynamics of multisensory responses in cat SC neurons. The results illustrate that locations within the spatial receptive fields (SRFs) of these neurons can be divided into those showing short-duration responses and long-duration response profiles. Most importantly, discharge duration appears to be a good determinant of multisensory integration, such that short-duration responses are typically associated with a high magnitude of multisensory integration (i.e., superadditive responses) while long-duration responses are typically associated with low integrative capacity. These results further reinforce the complexity of the integrative features of SC neurons and show that the large SRFs of these neurons are characterized by vastly differing temporal dynamics, dynamics that strongly shape the integrative capacity of these neurons.

  13. 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.

  14. 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.

  15. Is subjective duration a signature of coding efficiency?

    PubMed Central

    Eagleman, David M.; Pariyadath, Vani

    2009-01-01

    Perceived duration is conventionally assumed to correspond with objective duration, but a growing literature suggests a more complex picture. For example, repeated stimuli appear briefer in duration than a novel stimulus of equal physical duration. We suggest that such duration illusions appear to parallel the neural phenomenon of repetition suppression, and we marshal evidence for a new hypothesis: the experience of duration is a signature of the amount of energy expended in representing a stimulus, i.e. the coding efficiency. This novel hypothesis offers a unified explanation for almost a dozen illusions in the literature in which subjective duration is modulated by properties of the stimulus such as size, brightness, motion and rate of flicker. PMID:19487187

  16. Phonological Encoding and Phonetic Duration

    ERIC Educational Resources Information Center

    Fricke, Melinda Denise

    2013-01-01

    Studies of connected speech have repeatedly shown that the contextual predictability of a word is related to its phonetic duration; more predictable words tend to be produced with shorter duration, when other factors are controlled for (Aylett & Turk, 2004, 2006; Bell et al., 2003; Bell, Brenier, Gregory, Girand, & Jurafsky, 2009; Gahl,…

  17. Estimating the duration of speciation from phylogenies.

    PubMed

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

    2014-08-01

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

  18. Association of frontal QRS-T angle--age risk score on admission electrocardiogram with mortality in patients admitted with an acute coronary syndrome.

    PubMed

    Lown, Mark T; Munyombwe, Theresa; Harrison, Wendy; West, Robert M; Hall, Christiana A; Morrell, Christine; Jackson, Beryl M; Sapsford, Robert J; Kilcullen, Niamh; Pepper, Christopher B; Batin, Phil D; Hall, Alistair S; Gale, Chris P

    2012-02-01

    Risk assessment is central to the management of acute coronary syndromes. Often, however, assessment is not complete until the troponin concentration is available. Using 2 multicenter prospective observational studies (Evaluation of Methods and Management of Acute Coronary Events [EMMACE] 2, test cohort, 1,843 patients; and EMMACE-1, validation cohort, 550 patients) of unselected patients with acute coronary syndromes, a point-of-admission risk stratification tool using frontal QRS-T angle derived from automated measurements and age for the prediction of 30-day and 2-year mortality was evaluated. Two-year mortality was lowest in patients with frontal QRS-T angles <38° and highest in patients with frontal QRS-T angles >104° (44.7% vs 14.8%, p <0.001). Increasing frontal QRS-T angle-age risk (FAAR) scores were associated with increasing 30-day and 2-year mortality (for 2-year mortality, score 0 = 3.7%, score 4 = 57%; p <0.001). The FAAR score was a good discriminator of mortality (C statistics 0.74 [95% confidence interval 0.71 to 0.78] at 30 days and 0.77 [95% confidence interval 0.75 to 0.79] at 2 years), maintained its performance in the EMMACE-1 cohort at 30 days (C statistics 0.76 (95% confidence interval 0.71 to 0.8] at 30 days and 0.79 (95% confidence interval 0.75 to 0.83] at 2 years), in men and women, in ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction, and compared favorably with the Global Registry of Acute Coronary Events (GRACE) score. The integrated discrimination improvement (age to FAAR score at 30 days and at 2 years in EMMACE-1 and EMMACE-2) was p <0.001. In conclusion, the FAAR score is a point-of-admission risk tool that predicts 30-day and 2-year mortality from 2 variables across a spectrum of patients with acute coronary syndromes. It does not require the results of biomarker assays or rely on the subjective interpretation of electrocardiograms.

  19. The pathophysiologic aspects and clinical implications of electrocardiographic parameters of ventricular conduction delay in repaired tetralogy of Fallot.

    PubMed

    Udink ten Cate, Floris E A; Sreeram, Narayanswami; Brockmeier, Konrad

    2014-01-01

    The 12-lead surface electrocardiogram is a valuable and feasible clinical tool in the management of patients following tetralogy of Fallot (TOF) repair. The importance of QRS duration in TOF patients has long been acknowledged. A prolonged QRS complex has been associated with increased risk for subsequent life-threatening ventricular arrhythmia and sudden cardiac death. Our current ability to risk-stratify TOF patients for malignant arrhythmogenic events primarily on the basis of QRS duration is rather limited. Nevertheless, increasing evidence suggests that QRS morphology and duration may be useful as surrogate markers of infundibular and regional right ventricular myocardial disease. The aim of this review is to provide a critical appraisal of the clinical implications of established and new electrocardiographic markers of ventricular conduction delay in TOF patients following surgical correction with a particular focus on QRS duration, lengthening, and fragmentation. In addition, the pathophysiological background of these parameters is addressed.

  20. 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…

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. Tilt changes of short duration

    USGS Publications Warehouse

    McHugh, Stuart

    1976-01-01

    Section I of this report contains a classification scheme for short period tilt data. For convenience, all fluctuations in the local tilt field of less than 24 hours duration will be designated SP (i.e., short period) tilt events. Three basic categories of waveshape appearance are defined, and the rules for naming the waveforms are outlined. Examples from tilt observations at four central California sites are provided. Section II contains some coseismic tilt data. Fourteen earthquakes in central California, ranging in magnitude from 2.9 to 5.2, were chosen for study on four tiltmeters within 10 source dimensions of the epicenters. The raw records from each of the four tiltmeters at the times of the earthquakes were photographed and are presented in this section. Section III contains documentation of computer programs used in the analysis of the short period tilt data. Program VECTOR computes the difference vector of a tilt event and displays the sequence of events as a head-to-tail vector plot. Program ONSTSP 1) requires two component digitized tilt data as input, 2) scales and plots the data, and 3) computes and displays the amplitude, azimuth, and normalized derivative of the tilt amplitude. Program SHARPS computes the onset sharpness, (i.e., the normalized derivative of the tilt amplitude at the onset of the tilt event) as a function of source-station distance from a model of creep-related tilt changes. Program DSPLAY plots the digitized data.

  6. 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.

  7. Sentence durations and accentedness judgments

    NASA Astrophysics Data System (ADS)

    Bond, Z. S.; Stockmal, Verna; Markus, Dace

    2003-04-01

    Talkers in a second language can frequently be identified as speaking with a foreign accent. It is not clear to what degree a foreign accent represents specific deviations from a target language versus more general characteristics. We examined the identifications of native and non-native talkers by listeners with various amount of knowledge of the target language. Native and non-native speakers of Latvian provided materials. All the non-native talkers spoke Russian as their first language and were long-term residents of Latvia. A listening test, containing sentences excerpted from a short recorded passage, was presented to three groups of listeners: native speakers of Latvian, Russians for whom Latvian was a second language, and Americans with no knowledge of either of the two languages. The listeners were asked to judge whether each utterance was produced by a native or non-native talker. The Latvians identified the non-native talkers very accurately, 88%. The Russians were somewhat less accurate, 83%. The American listeners were least accurate, but still identified the non-native talkers at above chance levels, 62%. Sentence durations correlated with the judgments provided by the American listeners but not with the judgments provided by native or L2 listeners.

  8. A Comparative Study in the Use of Brachial Photoplethysmography and the QRS Complex as Timing References in Determination of Pulse Transit Time

    DTIC Science & Technology

    2007-11-02

    splinted in each case to keep the brachial archery prominent. The probes were connected with flexible cable to the data acquisition unit. The subject was...pressure. A sample of data was taken during this period. A measurement of the distance from the detection point on the brachial archery to the...brachial archery , at the elbow, and produced a strong, if elusive, plethysmograph. The wider focus of this work is to explore a means for non

  9. Deletion of FoxO1 leads to shortening of QRS by increasing Na(+) channel activity through enhanced expression of both cardiac NaV1.5 and β3 subunit.

    PubMed

    Cai, Benzhi; Wang, Ning; Mao, Weike; You, Tao; Lu, Yan; Li, Xiang; Ye, Bo; Li, Faqian; Xu, Haodong

    2014-09-01

    Our in vitro studies revealed that a transcription factor, Forkhead box protein O1 (FoxO1), negatively regulates the expression of NaV1.5, a main α subunit of the cardiac Na(+) channel, by altering the promoter activity of SCN5a in HL-1 cardiomyocytes. The in vivo role of FoxO1 in the regulation of cardiac NaV1.5 expression remains unknown. The present study aimed to define the role of FoxO1 in the regulation of NaV1.5 expression and cardiac Na(+) channel activity in mouse ventricular cardiomyocytes and assess the cardiac electrophysiological phenotype of mice with cardiac FoxO1 deletion. Tamoxifen-induced and cardiac-specific FoxO1 deletion was confirmed by polymerase chain reaction (PCR). Cardiac FoxO1 deletion failed to result in either cardiac functional changes or hypertrophy as assessed by echocardiography and individual ventricular cell capacitances, respectively. Western blotting showed that FoxO1 was significantly decreased while NaV1.5 protein level was significantly increased in mouse hearts with FoxO1 deletion. Reverse transcription-PCR (RT-PCR) revealed that FoxO1 deletion led to an increase in NaV1.5 and Na(+) channel subunit β3 mRNA, but not β1, 2, and 4, or connexin 43. Whole patch-clamp recordings demonstrated that cardiac Na(+) currents were significantly augmented by FoxO1 deletion without affecting the steady-state activation and inactivation, leading to accelerated depolarization of action potentials in mouse ventricular cardiomyocytes. Electrocardiogram recordings showed that the QRS complex was significantly shortened and the P wave amplitude was significantly increased in conscious and unrestrained mice with cardiac FoxO1 deletion. NaV1.5 expression was decreased in the peri-infarct (border-zone) of mice with myocardial infarction and FoxO1 accumulated in the cardiomyocyte nuclei of chronic ischemic human hearts. Our findings indicate that FoxO1 plays an important role in the regulation of NaV1.5 and β3 subunit expressions as well as Na

  10. Correlates of Long Sleep Duration

    PubMed Central

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

    2012-01-01

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

  11. Usefulness of time interval between end of diastolic mitral annular velocity pattern and onset of QRS for predicting left ventricular end-diastolic pressure.

    PubMed

    Su, Ho-Ming; Lin, Tsung-Hsien; Voon, Wen-Chol; Lee, Kun-Tai; Chu, Chih-Sheng; Cheng, Kai-Hung; Yen, Hsueh-Wei; Lai, Wen-Ter; Sheu, Sheng-Hsiung

    2007-01-01

    Diastolic mitral annular motion may terminate earlier in patients with higher left ventricular end-diastolic pressure (LVEDP). It was therefore hypothesized that the time interval measured from the end of the diastolic mitral annular velocity pattern to the onset of QRS (the AQ interval) would be a useful parameter in predicting LVEDP. The aim of this study was to evaluate the relation between the AQ interval and LVEDP. Forty-six patients with suspected coronary artery disease who underwent Doppler echocardiographic studies and cardiac catheterization were included. LVEDP was determined using a micromanometer-tipped catheter. On univariate analysis, the AQ interval had positive correlations with the PR interval (r = 0.405, p = 0.005), transmitral E-wave velocity (r = 0.502, p <0.001), isovolumic contraction time (r = 0.635, p <0.001), and LVEDP (r = 0.514, p <0.001) and a negative correlation with E-wave deceleration time (r = -0.430, p = 0.003). After stepwise multiple linear regression analysis, the PR interval, transmitral E-wave velocity, and LVEDP were the independent predictors of the AQ interval (beta = 0.234, p = 0.033; beta = 0.331, p = 0.004; and beta = 0.350, p = 0.003, respectively). In conclusion, the AQ interval is a novel, simple, and easily obtained index in the prediction of LVEDP.

  12. IDF relationships for short duration rainfall

    NASA Astrophysics Data System (ADS)

    Montesarchio, Valeria; Napolitano, Francesco; Russo, Fabio; Spina, S.

    2013-10-01

    The intensity-duration-frequency (IDF) relationships bound rainfall intensity to duration and return period. These relationships are commonly used as an input in design of many hydraulic structures and drainage systems. Empirical IDF are estimated on the basis of recorded maximum annual precipitation of given durations, often ranging from 1 h to 24 h. For shorter durations, extrapolations are applied. In this paper, maximum annual precipitation for durations shorter than 1 h (namely, 30 min and 10 min) are evaluated using a rainfall disaggregation model and then used for the evaluation of the IDF relationship. A comparison of values obtained with the extrapolated values is then performed, and the results are discussed. Keywords: intensity-duration-frequency curves, rainfall disaggregation, entropy.

  13. 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.

  14. 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.

  15. 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,...

  16. 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

  17. 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…

  18. Duration Sensitivity Depends on Stimulus Familiarity

    ERIC Educational Resources Information Center

    Morewedge, Carey K.; Kassam, Karim S.; Hsee, Christopher K.; Caruso, Eugene M.

    2009-01-01

    When people are asked to assess or compare the value of experienced or hypothetical events, one of the most intriguing observations is their apparent insensitivity to event duration. The authors propose that duration insensitivity occurs when stimuli are evaluated in isolation because they typically lack comparison information. People should be…

  19. 12 CFR 1252.2 - Effective duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Effective duration. 1252.2 Section 1252.2 Banks and Banking FEDERAL HOUSING FINANCE AGENCY ENTERPRISES PORTFOLIO HOLDINGS § 1252.2 Effective duration. This part shall be in effect for each Enterprise so long as— (a) This part has not been...

  20. [Difficulties of persistent repolarization following normalization of the QRS wave in the Wolff-Parkinson-White syndrome].

    PubMed

    Laham, J; Frank, R; Fontaine, G; Artigou, Y; Heller, J; Gerbaux, A; Grosgogeat, Y

    1982-06-01

    The normalisation of the ventricular complex in the Wolff-Parkinson-White syndrome is often accompanied by changes in the repolarisation phase with a deep, symmetric and pointed T wave suggestive of coronary artery disease. In order to study this phenomenon we examined 29 cases of intermittent WPW, 13 of which had abnormalities of the normalised complex. Normalisation occurred spontaneously on 10 occasions, twice on exercise and once after Ajmaline. In the majority of cases (9/13) the preexcitation was a right (4 cases) or left (5 cases) posterior pathway and the T waves were abnormal in the posterior leads (II, III and AVF). In left lateral preexcitation the T waves were negative in lead 1 and AVL. The T wave changes seem to be related to the topography of the preexcitation pathway. They gradually disappeared in the 3 cases in which preexcitation had not recurred. The age of the patients (11 to 45 years, average 31 years) or normal coronary angiography, performed in 3 cases, excluded coronary pathology as did the close relationship between the topography of the preexcitation and the T wave changes and the gradual disappearance of the abnormalities in the cases where preexcitation did not recur. This phenomenon, related to abnormal ventricular activation, seems to be comparable to the changes in ventricular repolarisation observed on termination of ventricular pacing, on the regression of certain intermittent left bundle branch blocks and perhaps, in some cases, of the post-ventricular tachycardia syndrome.

  1. Autonomic Recovery after Long-Duration Spaceflight

    NASA Astrophysics Data System (ADS)

    Couckuyt, Kurt; Verheyden, Bart; Liu, Jiexin; Aubert, Andre E.

    2008-06-01

    In this study, the recovery of cardiovascular autonomic modulation after long-duration spaceflight (6 months) is evaluated over a period of 30 days. Results from long-duration spaceflight were compared with the results obtained in astronauts who spent about 10 days in space. It is expected that cardiovascular recovery after spaceflight takes longer when the time spent in weightlessness is extended. Six male astronauts who spent 6 months in space in the ISS participated in the study. It was found that after long duration spaceflight, there is a sympathetic autonomic dominance resulting in post-flight orthostatic tachycardia. Surprisingly, no differences were found in autonomic changes and post-flight recovery after long-duration spaceflight compared to post-flight autonomic control after short-duration spaceflight.

  2. Electropermeabilization of mammalian cells to macromolecules: control by pulse duration.

    PubMed Central

    Rols, M P; Teissié, J

    1998-01-01

    Membrane electropermeabilization to small molecules depends on several physical parameters (pulse intensity, number, and duration). In agreement with a previous study quantifying this phenomenon in terms of flow (Rols and Teissié, Biophys. J. 58:1089-1098, 1990), we report here that electric field intensity is the deciding parameter inducing membrane permeabilization and controls the extent of the cell surface where the transfer can take place. An increase in the number of pulses enhances the rate of permeabilization. The pulse duration parameter is shown to be crucial for the penetration of macromolecules into Chinese hamster ovary cells under conditions where cell viability is preserved. Cumulative effects are observed when repeated pulses are applied. At a constant number of pulses/pulse duration product, transfer of molecules is strongly affected by the time between pulses. The resealing process appears to be first-order with a decay time linearly related to the pulse duration. Transfer of macromolecules to the cytoplasm can take place only if they are present during the pulse. No direct transfer is observed with a postpulse addition. The mechanism of transfer of macromolecules into cells by electric field treatment is much more complex than the simple diffusion of small molecules through the electropermeabilized plasma membrane. PMID:9726943

  3. Assessment of cardiac resynchronisation therapy in patients with wide QRS and non-specific intraventricular conduction delay: rationale and design of the multicentre randomised NICD-CRT study

    PubMed Central

    Eschalier, Romain; Ploux, Sylvain; Pereira, Bruno; Clémenty, Nicolas; Da Costa, Antoine; Defaye, Pascal; Garrigue, Stéphane; Gourraud, Jean-Baptiste; Gras, Daniel; Guy-Moyat, Benoît; Leclercq, Christophe; Mondoly, Pierre; Bordachar, Pierre

    2016-01-01

    Introduction Cardiac resynchronisation therapy (CRT) was initially developed to treat patients with left bundle branch block (LBBB). However, many patients with heart failure have a widened QRS but neither left-BBB nor right-BBB; this is called non-specific intraventricular conduction delay (NICD). It is unclear whether CRT is effective in this subgroup of patients. Methods and analysis The NICD-CRT study is a prospective, double-blind, randomised (1:1), parallel-arm, multicentre trial comparing the effects of CRT in patients with heart failure, a reduced left ventricular ejection fraction (LVEF <35%) and NICD, who have been implanted with a device (CRT-pacemaker or CRT-defibrillator) that has or has not been activated. Enrolment began on 15 July 2015 and should finish within 3 years; 40 patients have already been randomised and 11 centres have agreed to participate. The primary end point is the comparison of the proportion of patients improved, unchanged or worsened over the subsequent 12 months. 100 patients per group are required to demonstrate a difference between groups with a statistical power of 90%, a type I error of 0.05% (two-sided) and a loss to follow-up of 10%. This trial will add substantially to the modest amount of existing data on CRT in patients with NICD and should reduce uncertainty for guidelines and clinical practice when added to the pool of current information. Ethics and dissemination Local ethics committee authorisations have been obtained since May 2015. We will publish findings from this study in a peer-reviewed scientific journal and present results at national and international conferences. Trial registration number NCT02454439; pre-results. PMID:27836874

  4. Attentional entrainment and perceived event duration

    PubMed Central

    McAuley, J. Devin; Fromboluti, Elisa Kim

    2014-01-01

    This study considered the contribution of dynamic attending theory (DAT) and attentional entrainment to systematic distortions in perceived event duration. Three experiments were conducted using an auditory oddball paradigm, in which listeners judged the duration of a deviant (oddball) stimulus embedded within a series of identical (standard) stimuli. To test for a role of attentional entrainment in perceived oddball duration, oddballs were presented at either temporally expected (on time) or unexpectedly early or late time points relative to extrapolation of the context rhythm. Consistent with involvement of attentional entrainment in perceived duration, duration judgements about the oddball were least distorted when the oddball occurred on time with respect to the entrained rhythm, whereas durations of early and late oddballs were perceived to be shorter and longer, respectively. This pattern of results was independent of the absolute time interval preceding the oddball. Moreover, as expected, an irregularly timed sequence context weakened observed differences between oddballs with on-time and late onsets. Combined with other recent work on the role of temporal preparation in duration distortions, the present findings allot at least a portion of the oddball effect to increased attention to events that are more expected, rather than on their unexpected nature per se. PMID:25385779

  5. 18 CFR 430.33 - Duration.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... REGULATIONS GROUND WATER PROTECTION AREA: PENNSYLVANIA § 430.33 Duration. The delineation and declaration of the Southeastern Pennsylvania Ground Water Protected Area made pursuant to this regulation, and...

  6. 18 CFR 430.33 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... REGULATIONS GROUND WATER PROTECTION AREA: PENNSYLVANIA § 430.33 Duration. The delineation and declaration of the Southeastern Pennsylvania Ground Water Protected Area made pursuant to this regulation, and...

  7. 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.

  8. [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.

  9. 14 CFR 420.43 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... TRANSPORTATION LICENSING LICENSE TO OPERATE A LAUNCH SITE License Terms and Conditions § 420.43 Duration. A license to operate a launch site remains in effect for five years from the date of issuance...

  10. Perceived duration of chromatic and achromatic light.

    PubMed

    Kojima, Haruyuki; Kawabata, Yasuhiro

    2012-01-15

    Luminance and color information are considered to be processed in parallel systems. The integration of information from these two separate systems is crucial for the visual system to produce a coherent percept. To investigate how luminance and color lights are perceived in time, we measured the perceived duration of light stimuli with and without colors in a paradigm involving simultaneous perception with presentation of two successive stimulus frames. Luminance contrast and color contrast of the stimuli were set with a chromatic substitution technique. In Experiment 1, the perceived duration of both chromatic stimuli and achromatic stimuli increased as the luminance contrast decreased. Experiment 2 tested if the duration of the percept was influenced by color contrast which was defined by colorimetric purity of the stimuli, when luminance contrast was set as low as practically possible. The result showed that the duration of the percept decreased with increasing color contrast of the stimuli. Moreover, Experiment 3 demonstrated that the trend of perceived duration was consistent with the four primary colors, provided that the effective color contrast of stimulus was corrected based on the contrast sensitivity to the color. These experiments indicate that, with a high luminance contrast level, perceived duration of a stimulus is predominantly defined by luminance contrast, whereas in low luminance contrast conditions, the duration depends on the color contrast. The perceived duration of color stimuli showed an "inverse color contrast effect", similar to the well-known "inverse intensity effect" for luminance stimuli. The similarities and the differences between the two systems, as well as their priorities in processing temporal information of visual stimuli are further discussed.

  11. Interaction of Factors Related to Lactation Duration

    PubMed Central

    Boettcher, Joan P; Chezem, Jo Carol; Roepke, Judith; Whitaker, Tracy Adams

    1999-01-01

    Perceived social support and interpersonal dependency were studied as potential factors associated with lactation duration based upon previous breastfeeding experience. Inexperienced breastfeeding mothers perceived more social support than experienced breastfeeding mothers did. Perceived social support was not significantly correlated with lactation duration. An ancillary finding was that women providing a combination of breast milk and human milk substitutes had significantly lower social self-confidence than did mothers providing breast milk exclusively. PMID:22945984

  12. 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.

  13. Strong motion duration and earthquake magnitude relationships

    SciTech Connect

    Salmon, M.W.; Short, S.A.; Kennedy, R.P.

    1992-06-01

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

  14. 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

  15. 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

  16. 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).

  17. Power supplies for long duration balloon flights

    NASA Astrophysics Data System (ADS)

    Lichfield, Ernest W.

    Long duration balloon flights require more electrical power than can be carried in primary batteries. This paper provides design information for selecting rechargeable batteries and charging systems. Solar panels for recharging batteries are discussed, with particular emphasis on cells mounting suitable for balloon flights and panel orientation for maximum power collection. Since efficient utilization of power is so important, modern DC to DC power conversion techniques are presented. On short flights of 1 day or less, system designers have not been greatly concerned with battery weight. But, with the advent of long duration balloon flights using superpressure balloons, anchor balloon systems, and RACOON balloon techniques, power supplies and their weight become of prime importance. The criteria for evaluating power systems for long duration balloon flights is performance per unit weight. Instrumented balloon systems have flown 44 days. For these very long duration flights, batteries recharged from solar cells are the only solution. For intermediate flight duration, say less than 10 days, the system designer should seriously consider using primary cells. The National Center for Atmospheric Research is sponsored by the National Science Foundation. Any opinions, findings and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the National Science Foundation.

  18. Evidence that gestation duration and lactation duration are coupled traits in primates.

    PubMed

    Dubman, Evgenia; Collard, Mark; Mooers, Arne Ø

    2012-12-23

    Gestation duration and lactation duration are usually treated as independently evolving traits in primates, but the metabolic theory of ecology (MTE) suggests both durations should be determined by metabolic rate. We used phylogenetic generalized least-squares linear regression to test these different perspectives. We found that the allometries of the durations are divergent from each other and different from the scaling exponent predicted by the MTE (0.25). Gestation duration increases much more slowly (0.06 < m < 0.12), and lactation duration much more quickly (0.36 < m < 0.52) with body mass than the MTE predicts. By contrast, we found that the combined duration of gestation and lactation is consistent with the MTE's predictions (0.22 < m < 0.35). These results suggest that gestation duration and lactation duration might best be viewed as distinct but coupled adaptations. When transferring energy to their offspring, primate mothers must meet metabolically dictated physiological requirements while optimizing the timing of the switch from gestation to lactation in relation to some as-yet-unidentified body-size-related factor.

  19. Does knowing speaker sex facilitate vowel recognition at short durations?

    PubMed

    Smith, David R R

    2014-05-01

    A man, woman or child saying the same vowel do so with very different voices. The auditory system solves the complex problem of extracting what the man, woman or child has said despite substantial differences in the acoustic properties of their voices. Much of the acoustic variation between the voices of men and woman is due to changes in the underlying anatomical mechanisms for producing speech. If the auditory system knew the sex of the speaker then it could potentially correct for speaker sex related acoustic variation thus facilitating vowel recognition. This study measured the minimum stimulus duration necessary to accurately discriminate whether a brief vowel segment was spoken by a man or woman, and the minimum stimulus duration necessary to accuately recognise what vowel was spoken. Results showed that reliable vowel recognition precedesreliable speaker sex discrimination, thus questioning the use of speaker sex information in compensating for speaker sex related acoustic variation in the voice. Furthermore, the pattern of performance across experiments where the fundamental frequency and formant frequency information of speaker's voices were systematically varied, was markedly different depending on whether the task was speaker-sex discrimination or vowel recognition. This argues for there being little relationship between perception of speaker sex (indexical information) and perception of what has been said (linguistic information) at short durations.

  20. 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.

  1. 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.

  2. Latent profile approach to duration of stalking.

    PubMed

    Björklund, Katja; Häkkänen-Nyholm, Helinä; Sheridan, Lorraine; Roberts, Karl; Tolvanen, Asko

    2010-07-01

    Stalking behavior and victim-stalker relationship are often the principal known factors in a stalking case. Thus, they are of great importance when trying to identify factors contributing to stalking duration. The present study aims to identify distinct subgroups of stalking victims based on measures of behavioral stalking dimensions. These victim subgroups, stalking dimensions, and victim-stalker relationship are examined in relation to stalking duration. Using a sample of 137 university students, latent profile analysis (LPA) revealed five distinct victim subgroups based on stalker behavior dimensions: surveillance, low-profile, social lurker, wide scope, and baseline stalkers. The subgroups were significantly related to stalking duration and explained a considerable amount of the variance along with the stalking dimensions and victim-stalker relationship. Connections to stalking literature and utility of person-orientated methods in stalking research are discussed.

  3. [Labor duration: from normality to dystocia].

    PubMed

    Kayem, G

    2015-04-01

    "Normal" labor has been surprisingly little studied in the past 60 years even though it is a central axis in obstetrics. Standards were proposed 60 years ago by Emmanuel Friedman and adopted by many countries to become then, driven from Dublin school, the conditions allowing the management of labor: rupture of membranes and oxytocin with, in case of failure for dynamic dystocia, cesarean. Recent data have suggested that labor duration had changed since the 1960s. Changes in women's characteristics and in obstetric practice especially with the widespread use of oxytocin and realization of epidural may have an impact on labor duration. Current studies suggest that it may be possible to authorize longer labor duration without significant increase in maternal or neonatal morbidity. However, it is premature to change practices following the latest American recommendations without prior studies.

  4. 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.

  5. 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

  6. 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).

  7. 14 CFR 21.77 - Duration.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... surrendered, superseded, revoked, or otherwise terminated, provisional type certificates and amendments... effective for twelve months after the date of issue. (d) An amendment to a Class I or Class II provisional type certificate is effective for the duration of the amended certificate. (e) A provisional...

  8. The Course and Duration of Crisis.

    ERIC Educational Resources Information Center

    Lewis, Marc S.; And Others

    1979-01-01

    Psychological tests were administered to a crisis group undergoing surgery for cancer and to a comparison group on the night before surgery and thereafter at three-week intervals. Results indicated significant psychological changes only in the crisis group. Duration of crisis was greater than six weeks but less than seven months. (Author)

  9. 14 CFR 21.159 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Duration. 21.159 Section 21.159 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION... Administrator, or the location of the manufacturing facility is changed....

  10. 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.

  11. 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.

  12. 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)

  13. A Short-Duration Gel Diffusion Experiment.

    ERIC Educational Resources Information Center

    Mulcahy, D. E.

    1980-01-01

    Described is a gel diffusion experiment that permits the completion of duplicate diffusion runs within a three-hour laboratory session. Information included for the short-duration gel diffusion experiment is the diffusion cell, the experiment, data treatment, and the expected results of the experiment. (Author/DS)

  14. Iterated rippled noise discrimination at long durations.

    PubMed

    Yost, William A

    2009-09-01

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

  15. 14 CFR 21.443 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Duration. 21.443 Section 21.443 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Designated Alteration Station Authorization Procedures § 21.443...

  16. 14 CFR 21.313 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Duration. 21.313 Section 21.313 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Approval of Materials, Parts, Processes, and Appliances § 21.313...

  17. 5 CFR 330.1102 - Duration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Duration. 330.1102 Section 330.1102 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS RECRUITMENT, SELECTION, AND PLACEMENT (GENERAL) Federal Employment Priority Consideration Program for Displaced Employees of...

  18. 5 CFR 330.1102 - Duration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Duration. 330.1102 Section 330.1102 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS RECRUITMENT, SELECTION, AND PLACEMENT (GENERAL) Federal Employment Priority Consideration Program for Displaced Employees of...

  19. Electrocorticogram encoding of upper extremity movement duration.

    PubMed

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

    2014-01-01

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

  20. 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

  1. Efficiency, effectiveness, and duration of stroke rehabilitation.

    PubMed

    Shah, S; Vanclay, F; Cooper, B

    1990-02-01

    This prospective multicenter study identifies the variables significant in the prediction of rehabilitation efficiency, achievement of rehabilitation potential and duration of rehabilitation stay in 258 persons with a first stroke admitted to comprehensive inpatient rehabilitation in Brisbane, Australia, during 1984. All three dependent variables were poorly predicted, with only 17% of the variance in rehabilitation efficiency, only 30% of the variance in achievement of rehabilitation potential, and only 22% of the variance in duration of rehabilitation stay explained. Unlike other reports, we considered most of the major medical (side of paralysis, stroke etiology, site of the lesion, arterial distribution affected, etc.), rehabilitative (initial Barthel Index score, interval from stroke onset to acute-care hospital admission, interval from hospital admission to rehabilitation commencement, neurologic measures, etc.), and demographic (age, years of education, occupation, ethnicity, etc.) variables. The high proportion of unexplained variance is likely to be due to nonmedical factors influencing the selection of patients for rehabilitation.

  2. 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.

  3. Localization of Short Duration Periodic Signals

    DTIC Science & Technology

    2013-09-30

    the localization of multiple interfering sperm whales using multi- sensor time difference of arrival”, 130 Journal of the Acoustical Society of...often make short duration periodic signals such as clicks. It is common to locate whales by measuring the time difference for the same click...can occur when the sources are whales in a pod. In this case, a set of hyperbolic solutions will be created for each source and many false

  4. Underwater loudness for pure tones: Duration effects

    NASA Astrophysics Data System (ADS)

    Cudahy, Edward A.; Schwaller, Derek; Fothergill, David; Wolgemuth, Keith

    2003-04-01

    The loudness of underwater pure tones was measured by loudness matching for pure tones from 100 to 16,000 Hz. The standard was a one second tone at 1000 Hz. The signal duration was varied from 20 milliseconds to 5 seconds. Subjects were instructed to match the loudness of the comparison tone at one of the test frequencies to the loudness of the standard tone. Loudness was measured at the threshold, the most comfortable loudness, and the maximum tolerable loudness. The intensity of the standard was varied randomly across the test series. The subjects were bareheaded U.S. Navy divers tested at a depth of 3 meters. All subjects had normal in-air hearing. Tones were presented to the right side of the subject from an array of underwater sound projectors. The sound pressure level was calibrated at the location of the subject's head with the subject absent. Loudness increased and threshold decreased as duration increased. The effect was greatest at the lowest and highest frequencies. The shape of the loudness contours across frequency and duration derived from these measurements are different from in-air measurements. [Research supported by ONR.

  5. 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.

  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. Antenatal breastfeeding education for increasing breastfeeding duration

    PubMed Central

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

    2014-01-01

    Background Breastfeeding (BF) is well recognised as the best food for infants. The impact of antenatal BF education on the duration of BF has not been evaluated. Objectives To evaluate the effectiveness of antenatal BF education for increasing BF initiation and duration. Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (21 April 2010), CENTRAL (The Cochrane Library 2010, Issue 2), MEDLINE (1966 to April 2010) and SCOPUS (January 1985 to April 2010). We contacted experts and searched reference lists of retrieved articles. We updated the search of the Pregnancy and Childbirth Group’s Trials Register on 28 September 2011 and added the results to the awaiting classification section of the review. Selection criteria All identified published, unpublished and ongoing randomised controlled trials (RCTs) assessing the effect of formal antenatal BF education or comparing two different methods of formal antenatal BF education, on duration of BF. We excluded RCTs that also included intrapartum or postpartum BF education. Data collection and analysis We assessed all potential studies identified as a result of the search strategy. Two review authors extracted data from each included study using the agreed form and assessed risk of bias. We resolved discrepancies through discussion. Main results We included 17 studies with 7131 women in the review and 14 studies involving 6932 women contributed data to the analyses. We did not do any meta-analysis because there was only one study for each comparison. Five studies compared a single method of BF education with routine care. Peer counselling significantly increased BF initiation. Three studies compared one form of BF education versus another. No intervention was significantly more effective than another intervention in increasing initiation or duration of BF. Seven studies compared multiple methods versus a single method of BF education. Combined BF educational interventions were not

  8. 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.

  9. 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.

  10. 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.

  11. Training Concept for Long Duration Space Mission

    NASA Technical Reports Server (NTRS)

    O'Keefe, William

    2008-01-01

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

  12. 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.

  13. Long Duration Exposure Facility space optics handbook

    NASA Astrophysics Data System (ADS)

    Kemp, William T.; Taylor, Edward; Bloemker, Carl; White, Frank; Rensner, Gary; Watts, Alan

    1993-09-01

    This handbook provides a user a space optics design guide to materials based on the Long Duration Exposure Facility (LDEF) Space Optics Experiments. The materials covered are refractive optics, coatings, filters, mirrors, second surface mirrors, quartz microbalances, and fiber optics. The guide presents the data and the experience learned from the LDEF Space Optics Experiments in one volume in a user-friendly fashion. The data reported in the handbook are a compilation of the data published by the individual experimenters. Natural space environment data with an emphasis on the microparticle environment are also presented.

  14. Stretching Effects: High-intensity & Moderate-duration vs. Low-intensity & Long-duration.

    PubMed

    Freitas, S R; Vaz, J R; Bruno, P M; Andrade, R; Mil-Homens, P

    2016-03-01

    This study examined whether a high-intensity, moderate-duration bout of stretching would produce the same acute effects as a low-intensity, long-duration bout of stretching. 17 volunteers performed 2 knee-flexor stretching protocols: a high-intensity stretch (i. e., 100% of maximum tolerable passive torque) with a moderate duration (243.5 ± 69.5-s); and a low-intensity stretch (50% of tolerable passive torque) with a long duration (900-s). Passive torque at a given sub-maximal angle, peak passive torque, maximal range of motion (ROM), and muscle activity were assessed before and after each stretching protocol (at intervals of 1, 30 and 60 min). The maximal ROM and tolerable passive torque increased for all time points following the high-intensity stretching (p<0.05), but not after the low-intensity protocol (p>0.05). 1 min post-stretching, the passive torque decreased in both protocols, but to a greater extent in the low-intensity protocol. 30 min post-test, torque returned to baseline for the low-intensity protocol and had increased above the baseline for the high-intensity stretches. The following can be concluded: 1) High-intensity stretching increases the maximal ROM and peak passive torque compared to low-intensity stretching; 2) low-intensity, long-duration stretching is the best way to acutely decrease passive torque; and 3) high-intensity, moderate-duration stretching increases passive torque above the baseline 30 min after stretching.

  15. Estimating potential diapause duration in Calanus finmarchicus

    NASA Astrophysics Data System (ADS)

    Saumweber, Whitley J.; Durbin, Edward G.

    2006-11-01

    Deep basins in the Gulf of Maine act as refuge for a large population of diapausing Calanus finmarchicus during the summer and fall. This population acts as the primary seed population for Georges Bank in the spring and is thought to be composed primarily of individuals that developed during the previous spring bloom. The factors affecting growth and mortality in the summer-fall population are not well understood, however, and loss terms from advection and starvation may be large. To assess the potential energetic limitation and loss of C. finmarchicus from the Gulf of Maine basins, a new nitrogen-specific respiration model has been developed for the resting stage of the species. Stage C5 C. finmarchicus were collected during July, September, and December 2003 from Wilkinson and Georges Basins. Animals were collected using both MOCNESS tows and zooplankton samplers on the Johnson Sea Link II submersible. Metabolic rates were measured using a Micro-Oxymax gas analyzer and Winkler incubation techniques both at sea and on animals kept in culture on shore. Respiration rates measured in the field were not significantly different from those measured on shore, with a mean of 130 μmol O 2 gN -1 h -1 (14.4 μmol O 2 gC -1 h -1) at 0 °C and a Q10 of 2.77 (2.58 for carbon-specific respiration). Using the nitrogen-specific rates in conjunction with visual estimates of nitrogen weight and lipid stores, we derived a discrete function for predicting potential diapause duration based on an animal's length, oil sac volume, and the in situ temperature. The maximum potential diapause duration for a C5 C. finmarchicus is predicted to range from 280 days at 0 °C to approximately 90 days at 11 °C. The maximum potential diapause duration in the Gulf of Maine is predicted to be between 3.5 and 5.5 months. These results suggest that energetic limitation may play a role in controlling the population dynamics of diapausing C. finmarchicus in the Gulf of Maine. A reassessment of the

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Use of pacifiers and breastfeeding duration.

    PubMed

    Victora, C G; Tomasi, E; Olinto, M T; Barros, F C

    1993-02-13

    Pacifiers are widely used in many developing countries. Although their use is not recommended for breastfeeding infants, there have been no published reports on the association between pacifier use and risk of early weaning. In a study of 354 infants in Brazil, mothers were asked about pacifier use at age 1 month, duration of breastfeeding, and introduction of other foods. Among 249 children still breastfed at 1 month, the risk that a child would be weaned at any age between 1 and 24 months was higher in pacifier users than in non-users (hazard ratio 3.0, 95% CI 2.0-4.6). The association remained even after adjustment for the child's age, sex, birthweight, socioeconomic status, and age at introduction of bottle-feeding.

  2. Effects of methamphetamine on duration discrimination.

    PubMed

    Cevik, Münire Ozlem

    2003-08-01

    Experiments 1 and 2 address the controversy regarding the reliability of methamphetamine effects on interval timing. A temporal discrimination procedure was used, in which the rats were reinforced for pressing the left or the right levers after short and long signals, respectively. Methamphetamine (0.5 mg/kg sc) severely disrupted operant performance at 20-100 min after injection, which disabled the measurement of drug effects on temporal perception (Experiment 1). The same dose of methamphetamine shifted the psychometric function to the left at 100-180 min after injection, indicating an increase in subjective durations (Experiment 2). Although these results confirm the role of dopamine in interval timing, that a change in the speed of a neural clock mediates the methamphetamine-induced change in temporal perception is still a working hypothesis.

  3. 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.

  4. 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.

  5. 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.

  6. QT-Interval Duration and Mortality Rate

    PubMed Central

    Zhang, Yiyi; Post, Wendy S.; Dalal, Darshan; Blasco-Colmenares, Elena; Tomaselli, Gordon F.; Guallar, Eliseo

    2012-01-01

    Background Extreme prolongation or reduction of the QT interval predisposes patients to malignant ventricular arrhythmias and sudden cardiac death, but the association of variations in the QT interval within a reference range with mortality end points in the general population is unclear. Methods We included 7828 men and women from the Third National Health and Nutrition Examination Survey. Baseline QT interval was measured via standard 12-lead electrocardiographic readings. Mortality end points were assessed through December 31, 2006 (2291 deaths). Results After an average follow-up of 13.7 years, the association between QT interval and mortality end points was U-shaped. The multivariate-adjusted hazard ratios comparing participants at or above the 95th percentile of age-, sex-, race-, and R-R interval–corrected QT interval (≥439 milliseconds) with participants in the middle quintile (401 to <410 milliseconds) were 2.03 (95% confidence interval, 1.46-2.81) for total mortality, 2.55 (1.59-4.09) for mortality due to cardiovascular disease (CVD), 1.63 (0.96-2.75) for mortality due to coronary heart disease, and 1.65 (1.16-2.35) for non-CVD mortality. The corresponding hazard ratios comparing participants with a corrected QT interval below the fifth percentile (<377 milliseconds) with those in the middle quintile were 1.39 (95% confidence interval, 1.02-1.88) for total mortality, 1.35 (0.77-2.36) for CVD mortality, 1.02 (0.44-2.38) for coronary heart disease mortality, and 1.42 (0.97-2.08) for non-CVD mortality. Increased mortality also was observed with less extreme deviations of QT-interval duration. Similar, albeit weaker, associations also were observed with Bazett-corrected QT intervals. Conclusion Shortened and prolonged QT-interval durations, even within a reference range, are associated with increased mortality risk in the general population. PMID:22025428

  7. Short duration thermal metamorphism in CR chondrites

    NASA Astrophysics Data System (ADS)

    Briani, G.; Quirico, E.; Gounelle, M.; Paulhiac-Pison, M.; Montagnac, G.; Beck, P.; Orthous-Daunay, F.-R.; Bonal, L.; Jacquet, E.; Kearsley, A.; Russell, S. S.

    2013-12-01

    CR chondrites are considered as one of the most primitive classes of meteorites. Most of them experienced a mild aqueous alteration and show no evidence of significant effect of thermal metamorphism. We present here a search for low degree metamorphic effects in CR chondrites. We studied 15 CR chondrites using different metamorphic indicators: (1) structure and Ni content of metal grains; (2) hydration state of matrix; (3) structure and composition of organic matter. The different metamorphic indicators show that two of the analyzed CR chondrites, GRA 06100 and GRO 03116, experienced thermal metamorphism. Indeed, all of the metal grains in GRA 06100 and half of the metal grains in GRO 03116 show Ni-rich phases; the matrix of GRA 06100 is almost completely dehydrated, and the matrix of GRO 03116 is partially dehydrated; Raman spectra of organic matter in these two meteorites are clearly different from those obtained for organic matter in the other CR chondrites, which resemble Raman spectra of organic matter in unmetamorphosed, CM2 meteorites; IR spectra of insoluble organic matter extracted from GRA 06100 and GRO 03116 show lower carbonyl abundance and higher CH2/CH3 ratio with respect to organic matter of unmetamorphosed chondrites. The other CR chondrites analyzed here lack these characteristics and only show a few metal grains with Ni-rich inclusions. Our results also show that the metamorphic effects observed in GRA 06100 and GRO 03116 are different from those observed in type 3 chondrites, which experienced long-duration metamorphism of radiogenic origin. We infer that thermal processing in these two CRs extended over a short duration and was triggered by impacts.

  8. Prediction of Daily Flow Duration Curves and Streamflow for Ungauged Catchments Using Regional Flow Duration Curves

    EPA Science Inventory

    This study presents a method to predict flow duration curves (FDCs) and streamflow for ungauged catchments in the Mid-Atlantic Region, USA. We selected 29 catchments from the Appalachian Plateau, Ridge and Valley, and Piedmont physiographic provinces to develop and test the propo...

  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, 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....

  11. 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....

  12. 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....

  13. 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....

  14. Timing interventions in relation to temporomandibular joint closed lock duration: a systematic review of 'locking duration'.

    PubMed

    Al-Baghdadi, M; Durham, J; Steele, J

    2014-01-01

    Temporomandibular joint (TMJ) 'closed lock' (CL) is a clinical condition causing TMJ pain and limited mouth opening (painful locking) that is mostly attributed to disc displacement without reduction (DDwoR), or less commonly to anchored disc phenomenon (ADP). Both conditions are described clinically as CL that can be 'acute' or 'chronic' depending on the duration of locking. There is, however, no consensus about the duration of locking that defines the acute state and its effect on the success of interventions. This review paper, therefore, aims to provide: (i) a narrative review of the pathophysiological need for early intervention in DDwoR and the clinical implications of acute/chronic CL stages on the management pathway; (ii) a systematic review investigating the effects of locking duration on the success of interventions for CL management. Electronic and manual searches until mid-August 2013 were conducted for English-language studies of any design investigating the effects of non-surgical and surgical interventions for acute or chronic CL (DDwoR or ADP). A total of 626 records were identified, and 113 studies were included. Data extraction and quality assessment were completed for all included studies. Included studies were, however, heterogeneous and mostly of poor-quality leading to contradictory and inconsistent evidence on the effect of the duration of locking on treatment outcomes. Future high-quality trials investigating the effect of CL duration on treatment outcome are needed. At present, early intervention by 'unlock' mandibular manipulation seems to be the most practical and realistic approach that can be attempted first in every CL patient as an initial diagnostic/therapeutic approach.

  15. 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...

  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, 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...

  19. 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...

  20. Time in Language: Event Duration in Language Comprehension

    ERIC Educational Resources Information Center

    Coll-Florit, Marta; Gennari, Silvia P.

    2011-01-01

    This work investigates how we process and represent event duration in on-line language comprehension. Specifically, it examines how events of different duration are processed and what type of knowledge underlies their representations. Studies 1-4 examined verbs and phrases in different contexts. They showed that durative events took longer to…

  1. 5 CFR 1209.11 - Duration of stay; interim compliance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Duration of stay; interim compliance... WHISTLEBLOWING Stay Requests § 1209.11 Duration of stay; interim compliance. (a) Duration of stay. A stay becomes...) Interim compliance. An agency must immediately comply with an order granting a stay request. Although...

  2. 27 CFR 1.43 - Duration of permits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Duration of permits. 1.43 Section 1.43 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Amendment and Duration of Basic Permits § 1.43 Duration of permits. A basic permit shall continue in...

  3. 27 CFR 1.43 - Duration of permits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Duration of permits. 1.43 Section 1.43 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Amendment and Duration of Basic Permits § 1.43 Duration of permits. A basic permit shall continue in...

  4. 20 CFR 725.210 - Duration of augmented benefits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 4 2014-04-01 2014-04-01 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...

  5. 20 CFR 725.210 - Duration of augmented benefits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 4 2013-04-01 2013-04-01 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...

  6. 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...

  7. 20 CFR 725.210 - Duration of augmented benefits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 4 2012-04-01 2012-04-01 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...

  8. 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...

  9. 32 CFR 2001.12 - Duration of classification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Duration of classification. 2001.12 Section 2001.12 National Defense Other Regulations Relating to National Defense INFORMATION SECURITY OVERSIGHT... Classification § 2001.12 Duration of classification. (a) Determining duration of classification for...

  10. 32 CFR 2001.12 - Duration of classification.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Duration of classification. 2001.12 Section 2001.12 National Defense Other Regulations Relating to National Defense INFORMATION SECURITY OVERSIGHT... Classification § 2001.12 Duration of classification. (a) Determining duration of classification for...

  11. Dietary nutrients associated with short and long sleep duration. Data from a nationally representative sample.

    PubMed

    Grandner, Michael A; Jackson, Nicholas; Gerstner, Jason R; Knutson, Kristen L

    2013-05-01

    Short sleep duration is associated with weight gain and obesity, diabetes, cardiovascular disease, psychiatric illness, and performance deficits. Likewise, long sleep duration is also associated with poor physical and mental health. The role of a healthy diet in habitual sleep duration represents a largely unexplored pathway linking sleep and health. This study evaluated associations between habitual sleep parameters and dietary/nutritional variables obtained via the National Health and Nutrition Examination Survey (NHANES), 2007-2008. We hypothesized that habitual very short (<5h) short (5-6h) and long (9+h) sleep durations are associated with intake of a number of dietary nutrient variables. Overall, energy intake varied across very short (2036kcal), short (2201kcal), and long (1926kcal) sleep duration, relative to normal (2151kcal) sleep duration (p=0.001). Normal sleep duration was associated with the greatest food variety (17.8), compared to very short (14.0), short (16.5) and long (16.3) sleep duration (p<0.001). Associations between sleep duration were found across nutrient categories, with significant associations between habitual sleep duration and proteins, carbohydrates, vitamins and minerals. In stepwise analyses, significant contributors of unique variance included theobromine (long sleep RR=0.910, p<0.05), vitamin C (short sleep RR=0.890, p<0.05), tap water (short sleep RR=0.952, p<0.001; very short (<5h) sleep RR=0.941, p<0.05), lutein+zeaxanthin (short sleep RR=1.123, p<0.05), dodecanoic acid (long sleep RR=0.812, p<0.05), choline (long sleep RR=0.450, p=0.001), lycopene (very short (<5h) sleep RR=0.950, p<0.05), total carbohydrate (very short (<5h) sleep RR=0.494, p<0.05; long sleep RR=0.509, p<0.05), selenium (short sleep RR=0.670, p<0.01) and alcohol (long sleep RR=1.172, p<0.01). Overall, many nutrient variables were associated with short and/or long sleep duration, which may be explained by differences in food variety. Future studies should

  12. 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.

  13. Pegaso: Long durations balloons from polar regions

    NASA Astrophysics Data System (ADS)

    Romeo, G. R.; di Stefano, G. D. S.; di Felice, F. D. F.; Masi, S. M.; Cardillo, A. C.; Musso, I. M.; Ibba, R. I.; Palangio, P. P.; Caprara, F. C.; Peterzen, S. P.; Pegaso Group

    Launched from the Mario Zuccelli Station Baia Terra Nova in Antarctica during the 2005 06 austral summer the PEGASO-D payload lifted into the stratospheric anticyclone over the southern polar region This effort marks the first Long Duration Scientific payload to be launched from this location and is the fourth such payload launched in the polar regions Performing in the framework of the NOBILE AMUNDSEN collaborative LDB development between ASI-ARR The Italian Institute of Geophysics and Volcanology INGV with the sponsorship of the Italian Antarctic Program PNRA and the Italian Space Agency ASI designed and built the Ultra-Light system together with three Universities in Italy The Pegaso program has been created to investigate the Earth magnetic field and provide a precursor series of small payload launches for the bigger LDB program such as OLIMPO BOOMERanG and BArSPOrt through this collaboration between ASI and ARR The Italian scientific community aware of the big advantages that LDB balloons can offer to their experiments proposed to extend the LDB program to Southern polar regions besides performing launches from the newly initiated Nobile Amundsen Stratospheric Balloon Center in Svalbard Norway Three PEGASO Polar Explorer for Geomagnetics And other Scientific Observations payloads have been launched from the Svalbard No in collaboration with Andoya Rocket Range ASI and ISTAR Operations and logistics during the past two northern summers These stratospheric altitude m 35000 small 10kmc balloons have floated in the stratosphere between 14 to

  14. Svarna - vanga - a short duration toxicity study.

    PubMed

    Sharma; Gyaneshwar; Joshi, D; Aryya, N C; Pandey, V B

    1985-10-01

    Swarna - Vanga, an Ayurvedic preparation, is used in the treatment mainly of Pramehas (genitor urinary and metabolic disorders), Sveta Pradara (Leucorrhoea), Kasa - Swasa (Respiratory disorders), etc. The drug contains tin and sulphur as major components along with traces of mercury, iron and aluminum. According to modern point of view certain metals have been claimed toxic to both human and animal. Since Svarna - Vanga contains these metals, it is essential to screen out its toxic effect, if any, although it is claimed in Ayurveda that when a metal is processed as prescribed, it become non - toxic or the least toxic. Considering the above facts, an animal experiment was carried out for short duration (14 days) to screen the toxic effects of Svarna - Vanga (SV) in increasing doses of the drug starting from the maximum therapeutic dose (12.5 mg / 100 gm b.wt / day). The drug was found to have no toxic effects in tissues of the animal at doses of 12.5 mg and 25 mg / 100 gm b.wt. / day. Fine fatty vacuolization in liver and focal superficial mucosal degeneration and necrosis of small intestine confined to one animal each at dose of 50 mg / 100gm b.wt. and 100 mg/ 100 gm. b.wt. / day were observed. Our study indicates that the drug has no toxic effect on tissues at therapeutic dose.

  15. Long Duration Richtmyer-Meshkov Instability Experiments

    NASA Technical Reports Server (NTRS)

    Niederhaus, Charles; Hunyadi, Sarah; Jacobs, Jeffrey

    2003-01-01

    This experimental study investigates the Richtmyer-Meshkov (RM) instability of an interface between incompressible, miscible liquids with an initial 2-D sinusoidal perturbation. The experiments are conducted in NASA Glenn Research Center's 2.2 Second Drop Tower. The experimental rig is isolated from aerodynamic drag by a surrounding drag shield. The rig falls 7 1/2 inches relative to the drag shield during the 79 ft fall of the system. An internal spring-driven sled impacting a clay ball provides the impulsive acceleration while the package is at the top of the drop tower, with the package timed to release just after the impulsive acceleration is complete. The instability evolves for 2.2 seconds until the package impacts an air bag at the bottom of the drop tower. The increased duration of these experiments provides for more than twice the observation time of the RM instability in the non-linear regime that will allow for better experimental comparison with asymptotic theories of perturbation amplitude and velocity.

  16. Long Duration Space Materials Exposure (LDSE)

    NASA Technical Reports Server (NTRS)

    Allen, David; Schmidt, Robert

    1992-01-01

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

  17. 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.

  18. 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

  19. Mental Summation of Temporal Duration within and across Senses.

    PubMed

    Takahashi, Kohske; Watanabe, Katsumi

    2015-01-01

    Perceiving, memorizing, and estimating temporal durations are key cognitive functions in everyday life. In this study, a duration summation paradigm was used to examine whether summation of temporal durations introduces an underestimation or overestimation bias, and whether this bias is common to visual and auditory modalities. Two within- or across-modality stimuli were presented sequentially for variable durations. Participants were asked to reproduce the sum of the two durations (0.6-1.1 s). We found that the sum of two durations was overestimated regardless of stimulus modalities. A subsequent control experiment indicated that the overestimation bias arose from the summation process, not perceptual or memory processes. Furthermore, we observed strong positive correlations between the overestimation bias for different sensory modalities within participants. These results suggest that the sum of two durations is overestimated, and that supra-modal processes may be responsible for this overestimation bias.

  20. Exclusive breastfeeding duration and infant infection

    PubMed Central

    Quigley, M A; Carson, C; Sacker, A; Kelly, Y

    2016-01-01

    Background/Objectives: We estimated the risk of infection associated with the duration of exclusive breastfeeding (EBF). Subject/Methods: We analysed the data on 15 809 term, singleton infants from the UK Millennium Cohort Study. Infants were grouped according to months of EBF: never, <2, 2–4, 4–6 and 6 (the latter being World Health Organisation (WHO) policy since 2001: ‘post-2001 WHO policy'). Among those EBF for 4–6 months, we separated those who started solids, but not formula, before 6 months, and were still breastfeeding at 6 months (that is, WHO policy before 2001: ‘pre-2001 WHO policy'), from other patterns. Outcomes were infection in infancy (chest, diarrhoeal and ear). Results: EBF was not associated with the ear infection, but was associated with chest infection and diarrhoea. EBF for <4 months was associated with a significantly increased risk of chest infection (adjusted risk ratios (RR) 1.24–1.28) and diarrhoea (adjusted RRs 1.42–1.66) compared with the pre-2001 WHO policy. There was an excess risk of the chest infection (adjusted RR 1.19, 95% confidence interval (CI): 0.97–1.46) and diarrhoea (adjusted RR 1.66, 95% CI: 1.11, 2.47) among infants EBF for 4–6 months, but who stopped breastfeeding by 6 months, compared with the pre-2001 WHO policy. There was no significant difference in the risk of chest infection or diarrhoea in those fed according to the pre-2001 versus post-2001 WHO policy. Conclusions: There is an increased risk of infection in infants EBF for <4 months or EBF for 4–6 months who stop breastfeeding by 6 months. These results support current guidelines of EBF for either 4–6 or 6 months, with continued breastfeeding thereafter. PMID:27460268

  1. How hearing impairment affects sentence comprehension: using eye fixations to investigate the duration of speech processing.

    PubMed

    Wendt, Dorothea; Kollmeier, Birger; Brand, Thomas

    2015-04-24

    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.

  2. 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.

  3. Rashes and Exanthems on Long Duration Space Flights

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

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

  4. 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...

  5. 7 CFR 983.85 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

  6. 7 CFR 920.66 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  7. 7 CFR 946.73 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN WASHINGTON Order Regulating Handling Miscellaneous Provisions § 946.73 Duration of immunities. The...

  8. 7 CFR 920.66 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

  9. 7 CFR 929.72 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE CRANBERRIES GROWN IN STATES OF... Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

  10. 7 CFR 981.88 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges,...

  11. 7 CFR 966.87 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges,...

  12. 7 CFR 925.66 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE GRAPES GROWN IN A DESIGNATED AREA OF SOUTHEASTERN CALIFORNIA Miscellaneous Provisions § 925.66 Duration of immunities. The...

  13. 7 CFR 985.69 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE MARKETING ORDER REGULATING THE....69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  14. 7 CFR 948.87 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN COLORADO Order Regulating Handling Miscellaneous Provisions § 948.87 Duration of immunities. The...

  15. 7 CFR 993.87 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 993.87 Duration of immunities. The...

  16. 7 CFR 916.67 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE NECTARINES GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 916.67 Duration of immunities. The...

  17. 7 CFR 966.87 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Miscellaneous Provisions § 966.87 Duration of immunities. The benefits, privileges,...

  18. 7 CFR 981.88 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 981.88 Duration of immunities. The benefits, privileges,...

  19. 7 CFR 984.87 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges,...

  20. 7 CFR 984.87 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges,...

  1. 7 CFR 948.87 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN COLORADO Order Regulating Handling Miscellaneous Provisions § 948.87 Duration of immunities. The...

  2. 7 CFR 916.67 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE NECTARINES GROWN IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 916.67 Duration of immunities. The...

  3. 7 CFR 983.85 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  4. 7 CFR 927.72 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE PEARS GROWN IN OREGON AND WASHINGTON Order Regulating Handling Miscellaneous Provisions § 927.72 Duration of immunities. The...

  5. 7 CFR 993.87 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN CALIFORNIA Order Regulating Handling Miscellaneous Provisions § 993.87 Duration of immunities. The...

  6. 7 CFR 927.72 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE PEARS GROWN IN OREGON AND WASHINGTON Order Regulating Handling Miscellaneous Provisions § 927.72 Duration of immunities. The...

  7. 7 CFR 915.67 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE AVOCADOS GROWN IN SOUTH FLORIDA Order Regulating Handling Miscellaneous Provisions § 915.67 Duration of immunities. The...

  8. 7 CFR 985.69 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE MARKETING ORDER REGULATING THE....69 Duration of immunities. The benefits, privileges, and immunities conferred upon any person...

  9. 7 CFR 929.72 - Duration of immunities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE CRANBERRIES GROWN IN STATES OF... Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

  10. 7 CFR 915.67 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE AVOCADOS GROWN IN SOUTH FLORIDA Order Regulating Handling Miscellaneous Provisions § 915.67 Duration of immunities. The...

  11. 7 CFR 925.66 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE GRAPES GROWN IN A DESIGNATED AREA OF SOUTHEASTERN CALIFORNIA Miscellaneous Provisions § 925.66 Duration of immunities. The...

  12. 7 CFR 946.73 - Duration of immunities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN WASHINGTON Order Regulating Handling Miscellaneous Provisions § 946.73 Duration of immunities. The...

  13. 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.

  14. 50 CFR 222.403 - Duration of selection; effective date.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE SPECIES Observer Requirement § 222.403 Duration of selection; effective date. (a) Fisheries included...

  15. 50 CFR 222.403 - Duration of selection; effective date.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE SPECIES Observer Requirement § 222.403 Duration of selection; effective date. (a) Fisheries included...

  16. 50 CFR 222.403 - Duration of selection; effective date.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE SPECIES Observer Requirement § 222.403 Duration of selection; effective date. (a) Fisheries included...

  17. 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.

  18. 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,...

  19. 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,...

  20. 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,...

  1. 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,...

  2. 5 CFR 843.303 - Marriage duration requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 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,...

  3. 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...

  4. 10 CFR 52.26 - Duration of permit.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 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. 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...

  6. 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,...

  7. 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...

  8. 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,...

  9. 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...

  10. 10 CFR 52.104 - Duration of combined license.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 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...

  11. 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,...

  12. 10 CFR 52.104 - Duration of combined license.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 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...

  13. 10 CFR 52.26 - Duration of permit.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  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. 14 CFR 1203.702 - Duration of classification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Duration of classification. 1203.702 Section 1203.702 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION INFORMATION SECURITY PROGRAM Foreign Government Information § 1203.702 Duration of classification. Unless the guidelines...

  20. 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...

  1. 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...

  2. 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 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...

  3. 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 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...

  4. 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...

  5. 40 CFR 166.45 - Duration of crisis exemption.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 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. 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…

  7. 22 CFR 709.6 - Suspension duration criteria.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Suspension duration criteria. 709.6 Section 709.6 Foreign Relations OVERSEAS PRIVATE INVESTMENT CORPORATION ADMINISTRATIVE PROVISIONS FOREIGN CORRUPT PRACTICES ACT OF 1977 § 709.6 Suspension duration criteria. Factors which the President...

  8. 22 CFR 709.6 - Suspension duration criteria.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Suspension duration criteria. 709.6 Section 709.6 Foreign Relations OVERSEAS PRIVATE INVESTMENT CORPORATION ADMINISTRATIVE PROVISIONS FOREIGN CORRUPT PRACTICES ACT OF 1977 § 709.6 Suspension duration criteria. Factors which the President...

  9. 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....

  10. 34 CFR 690.6 - Duration of student eligibility.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Duration of student eligibility. 690.6 Section 690.6... Duration of student eligibility. (a) Except as provided in paragraphs (c) and (d) of this section, a student is eligible to receive a Federal Pell Grant for the period of time required to complete his or...

  11. 34 CFR 690.6 - Duration of student eligibility.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 4 2011-07-01 2011-07-01 false Duration of student eligibility. 690.6 Section 690.6... Definitions § 690.6 Duration of student eligibility. (a) Except as provided in paragraphs (c) and (d) of this section, a student is eligible to receive a Federal Pell Grant for the period of time required to...

  12. 34 CFR 690.6 - Duration of student eligibility.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 4 2013-07-01 2013-07-01 false Duration of student eligibility. 690.6 Section 690.6... Definitions § 690.6 Duration of student eligibility. (a) Except as provided in paragraphs (c) and (d) of this section, a student is eligible to receive a Federal Pell Grant for the period of time required to...

  13. 34 CFR 690.6 - Duration of student eligibility.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 4 2014-07-01 2014-07-01 false Duration of student eligibility. 690.6 Section 690.6... Definitions § 690.6 Duration of student eligibility. (a) Except as provided in paragraphs (c) and (d) of this section, a student is eligible to receive a Federal Pell Grant for the period of time required to...

  14. 34 CFR 690.6 - Duration of student eligibility.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 4 2012-07-01 2012-07-01 false Duration of student eligibility. 690.6 Section 690.6... Definitions § 690.6 Duration of student eligibility. (a) Except as provided in paragraphs (c) and (d) of this section, a student is eligible to receive a Federal Pell Grant for the period of time required to...

  15. 40 CFR 166.28 - Duration of exemption.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Duration of exemption. 166.28 Section 166.28 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS..., Quarantine, and Public Health Exemptions § 166.28 Duration of exemption. (a) Specific or public...

  16. 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... THE TREASURY (CONTINUED) ENTRY OF MERCHANDISE Powers of Attorney § 141.34 Duration of power of attorney. Powers of attorney issued by a partnership shall be limited to a period not to exceed 2...

  17. 40 CFR 147.2910 - Duration of authorization by rule.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Duration of authorization by rule. 147.2910 Section 147.2910 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER... Mineral Reserve-Class II Wells § 147.2910 Duration of authorization by rule. Existing Class II...

  18. 49 CFR 385.715 - Duration of safety monitoring system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Duration of safety monitoring system. 385.715... SAFETY FITNESS PROCEDURES Safety Monitoring System for Non-North American Carriers § 385.715 Duration of safety monitoring system. (a) Each non-North America-domiciled carrier subject to this subpart...

  19. 49 CFR 385.117 - Duration of safety monitoring system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Duration of safety monitoring system. 385.117... SAFETY FITNESS PROCEDURES Safety Monitoring System for Mexico-Domiciled Carriers § 385.117 Duration of safety monitoring system. (a) Each Mexico-domiciled carrier subject to this subpart will remain in...

  20. 49 CFR 385.715 - Duration of safety monitoring system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Duration of safety monitoring system. 385.715... SAFETY FITNESS PROCEDURES Safety Monitoring System for Non-North American Carriers § 385.715 Duration of safety monitoring system. (a) Each non-North America-domiciled carrier subject to this subpart...

  1. 49 CFR 385.117 - Duration of safety monitoring system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Duration of safety monitoring system. 385.117... SAFETY FITNESS PROCEDURES Safety Monitoring System for Mexico-Domiciled Carriers § 385.117 Duration of safety monitoring system. (a) Each Mexico-domiciled carrier subject to this subpart will remain in...

  2. 49 CFR 385.715 - Duration of safety monitoring system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Duration of safety monitoring system. 385.715... SAFETY FITNESS PROCEDURES Safety Monitoring System for Non-North American Carriers § 385.715 Duration of safety monitoring system. (a) Each non-North America-domiciled carrier subject to this subpart...

  3. 49 CFR 385.715 - Duration of safety monitoring system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Duration of safety monitoring system. 385.715... SAFETY FITNESS PROCEDURES Safety Monitoring System for Non-North American Carriers § 385.715 Duration of safety monitoring system. (a) Each non-North America-domiciled carrier subject to this subpart...

  4. 49 CFR 385.117 - Duration of safety monitoring system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Duration of safety monitoring system. 385.117... SAFETY FITNESS PROCEDURES Safety Monitoring System for Mexico-Domiciled Carriers § 385.117 Duration of safety monitoring system. (a) Each Mexico-domiciled carrier subject to this subpart will remain in...

  5. 49 CFR 385.117 - Duration of safety monitoring system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Duration of safety monitoring system. 385.117... SAFETY FITNESS PROCEDURES Safety Monitoring System for Mexico-Domiciled Carriers § 385.117 Duration of safety monitoring system. (a) Each Mexico-domiciled carrier subject to this subpart will remain in...

  6. 49 CFR 385.117 - Duration of safety monitoring system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Duration of safety monitoring system. 385.117... SAFETY FITNESS PROCEDURES Safety Monitoring System for Mexico-Domiciled Carriers § 385.117 Duration of safety monitoring system. (a) Each Mexico-domiciled carrier subject to this subpart will remain in...

  7. 49 CFR 385.715 - Duration of safety monitoring system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Duration of safety monitoring system. 385.715... SAFETY FITNESS PROCEDURES Safety Monitoring System for Non-North American Carriers § 385.715 Duration of safety monitoring system. (a) Each non-North America-domiciled carrier subject to this subpart...

  8. 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...

  9. 40 CFR 176.11 - Duration of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Duration of a tolerance. 176.11... TIME-LIMITED TOLERANCES FOR EMERGENCY EXEMPTIONS § 176.11 Duration of a tolerance. (a) Tolerances... specified by the Administrator. (b) Unless extended, tolerances will automatically expire and be...

  10. 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,...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 45 CFR 2400.53 - Duration of stipend.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Duration of stipend. 2400.53 Section 2400.53 Public Welfare Regulations Relating to Public Welfare (Continued) JAMES MADISON MEMORIAL FELLOWSHIP FOUNDATION FELLOWSHIP PROGRAM REQUIREMENTS Fellowship Stipend § 2400.53 Duration of stipend. Stipends...

  4. The duration of lactational amenorrhoea in urban Bangladeshi women.

    PubMed

    Rahman, Mahmudur; Mascie-Taylor, C G N; Rosetta, L

    2002-01-01

    The duration of lactational amenorrhoea, and infant feeding patterns and behaviour, were investigated in a sample of 97 mother-infant pairs living in a poor urban area of Dhaka, Bangladesh. A seven-hour time allocation method was used to determine the number of breast-feeding bouts and their duration. The seven-hour observation period was conducted on five occasions: at birth, 1 month, 4 months, 8 months and either 10 or 11 months. The median duration of lactational amenorrhoea was determined to be 24.07 weeks using survival analysis. Mothers who breast-fed their babies for longer and more frequently had, on average, a longer period of lactational amenorrhoea. There was no relationship between sociodemographic characteristics of the mother and duration of lactational amenorrhoea, nor was there any significant relationship between maternal anthropometry and birth weight of the baby and duration of lactational amenorrhoea, but there was a tendency for women with lower body mass index to have longer durations. Using the Cox proportional hazards model, the best predictor of duration of lactational amenorrhoea was the mean of months 0 and 1 durations of breast-feeding, adjusted for the mean frequencies for those months. The introduction of weaning food was also an important predictor.

  5. 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...

  6. 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…

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 10 CFR 52.147 - Duration of design approval.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Duration of design approval. 52.147 Section 52.147 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Standard Design Approvals § 52.147 Duration of design approval. A standard design approval issued...

  13. 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...

  14. 14 CFR 437.11 - Duration of an experimental permit.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Duration of an experimental permit. 437.11 Section 437.11 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.11 Duration of...

  15. 14 CFR 437.11 - Duration of an experimental permit.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Duration of an experimental permit. 437.11 Section 437.11 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.11 Duration of...

  16. 14 CFR 437.11 - Duration of an experimental permit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Duration of an experimental permit. 437.11 Section 437.11 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.11 Duration of...

  17. 14 CFR 437.11 - Duration of an experimental permit.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Duration of an experimental permit. 437.11 Section 437.11 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.11 Duration of...

  18. 14 CFR 437.11 - Duration of an experimental permit.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Duration of an experimental permit. 437.11 Section 437.11 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.11 Duration of...

  19. 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...

  20. 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...

  1. 7 CFR 929.72 - 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. 929.72 Section 929.72 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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,...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 7 CFR 984.87 - 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. 984.87 Section 984.87... Regulating Handling Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination hereof...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 7 CFR 929.72 - 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. 929.72 Section 929.72 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

  17. 7 CFR 929.72 - 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. 929.72 Section 929.72 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue...

  18. 7 CFR 984.87 - 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. 984.87 Section 984.87... Regulating Handling Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination hereof...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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,...

  9. 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...

  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 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  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 984.87 - 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. 984.87 Section 984.87... Regulating Handling Miscellaneous Provisions § 984.87 Duration of immunities. The benefits, privileges, and immunities conferred upon any person by virtue of this subpart shall cease upon the termination hereof...

  20. 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...

  1. 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...

  2. 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...

  3. 7 CFR 920.66 - 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. 920.66 Section 920.66 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Miscellaneous Provisions § 920.66 Duration of immunities. The benefits, priviliges, and immunities...

  4. 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...

  5. 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,...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 7 CFR 920.66 - 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. 920.66 Section 920.66 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Miscellaneous Provisions § 920.66 Duration of immunities. The benefits, priviliges, and immunities...

  13. 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...

  14. 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...

  15. 7 CFR 920.66 - 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. 920.66 Section 920.66 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Miscellaneous Provisions § 920.66 Duration of immunities. The benefits, priviliges, and immunities...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 14 CFR 145.55 - Duration and renewal of certificate.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Duration and renewal of certificate. 145.55 Section 145.55 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SCHOOLS AND OTHER CERTIFICATED AGENCIES REPAIR STATIONS Certification § 145.55 Duration...

  3. 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…

  4. Changes in apparent duration follow shifts in perceptual timing

    PubMed Central

    Bruno, Aurelio; Ayhan, Inci; Johnston, Alan

    2015-01-01

    It is well established that the apparent duration of moving visual objects is greater at higher as compared to slower speeds. Here we report the effects of acceleration and deceleration on the perceived duration of a drifting grating with average speed kept constant (10°/s).For acceleration, increasing the speed range progressively reduced perceived duration. The magnitude of apparent duration compression was determined by speed rather than temporal frequency and was proportional to speed range (independent of standard duration) rather than acceleration. The perceived duration reduction was also proportional to the standard length. The effects of increases and decreases in speed were highly asymmetric. Reducing speed through the interval induced a moderate increase in perceived duration. These results could not be explained by changes in apparent onset or offset or differences in perceived average speed between intervals containing increasing speed and intervals containing decreasing speed. Paradoxically, for intervals combining increasing speed and decreasing speed, compression only occurred when increasing speed occurred in the second half of the interval. We show that this pattern of results in the duration domain was concomitant with changes in the reported direction of apparent motion of Gaussian blobs, embedded in intervals of increasing or decreasing speed, that could be predicted from adaptive changes in the temporal impulse response function. We detected similar changes after flicker adaptation, suggesting that the two effects might be linked through changes in the temporal tuning of visual filters. PMID:26024450

  5. 10 CFR 52.147 - Duration of design approval.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Duration of design approval. 52.147 Section 52.147 Energy... Standard Design Approvals § 52.147 Duration of design approval. A standard design approval issued under this subpart is valid for 15 years from the date of issuance and may not be renewed. A design...

  6. 10 CFR 430.57 - Duration of temporary exemption.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 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...

  7. 10 CFR 430.57 - Duration of temporary exemption.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 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...

  8. 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...

  9. 10 CFR 430.57 - Duration of temporary exemption.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 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. 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...

  12. 25 CFR 211.27 - Duration of leases.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... duration if the lessee or the lessee's designee has commenced actual drilling by midnight of the last day of the primary term of the lease with a drilling rig designed to reach the total proposed depth, and... the primary term of lease duration (“commencement clause”) if drilling operations have...

  13. 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....

  14. 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...

  15. 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....

  16. 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....

  17. 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...

  18. 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....

  19. 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...

  20. 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....

  1. 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...

  2. 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...

  3. Diurnal variation of overdense meteor echo duration and ozone

    NASA Technical Reports Server (NTRS)

    Simek, Milos

    1992-01-01

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

  4. Perceived Duration Increases with Contrast, but Only a Little.

    PubMed

    Benton, Christopher P; Redfern, Annabelle S

    2016-01-01

    Recent adaptation studies provide evidence for early visual areas playing a role in duration perception. One explanation for the pronounced duration compression commonly found with adaptation is that it reflects adaptation-driven stimulus-specific reduction in neural activity in early visual areas. If this level of stimulus-associated neural activity does drive duration, then we would expect a strong effect of contrast on perceived duration as electrophysiological studies shows neural activity in early visual areas to be strongly related to contrast. We employed a spatially isotropic noise stimulus where the luminance of each noise element was independently sinusoidally modulated at 4 Hz. Participants matched the perceived duration of a high (0.9) or low (0.1) contrast stimulus to a previously presented standard stimulus (600 ms, contrast = 0.3). To achieve perceptually equivalent durations, the low contrast stimulus had to be presented for longer than the high contrast stimulus. This occurred when we controlled for stimulus size and when we adjusted for individual differences in perceived temporal frequency. Further, we show that the effect cannot be explained by shifts in perceived onset and offset and is not explained by a simple contrast-driven response bias. The direction of our results is clearly consistent with the idea that level of neural activity drives duration. However, the magnitude of the effect (~10% duration difference over a 0.9-0.1 contrast reduction) is in marked contrast to the larger duration distortions that can be found with repetition suppression and the oddball effect; particularly when these may be associated with smaller differences in neural activity than that expected from our contrast difference. Taken together, these results indicate that level of stimulus-related neural activity in early visual areas is unlikely to provide a general mechanism for explaining differences in perceived duration.

  5. Perceived Duration Increases with Contrast, but Only a Little

    PubMed Central

    Benton, Christopher P.; Redfern, Annabelle S.

    2016-01-01

    Recent adaptation studies provide evidence for early visual areas playing a role in duration perception. One explanation for the pronounced duration compression commonly found with adaptation is that it reflects adaptation-driven stimulus-specific reduction in neural activity in early visual areas. If this level of stimulus-associated neural activity does drive duration, then we would expect a strong effect of contrast on perceived duration as electrophysiological studies shows neural activity in early visual areas to be strongly related to contrast. We employed a spatially isotropic noise stimulus where the luminance of each noise element was independently sinusoidally modulated at 4 Hz. Participants matched the perceived duration of a high (0.9) or low (0.1) contrast stimulus to a previously presented standard stimulus (600 ms, contrast = 0.3). To achieve perceptually equivalent durations, the low contrast stimulus had to be presented for longer than the high contrast stimulus. This occurred when we controlled for stimulus size and when we adjusted for individual differences in perceived temporal frequency. Further, we show that the effect cannot be explained by shifts in perceived onset and offset and is not explained by a simple contrast-driven response bias. The direction of our results is clearly consistent with the idea that level of neural activity drives duration. However, the magnitude of the effect (~10% duration difference over a 0.9–0.1 contrast reduction) is in marked contrast to the larger duration distortions that can be found with repetition suppression and the oddball effect; particularly when these may be associated with smaller differences in neural activity than that expected from our contrast difference. Taken together, these results indicate that level of stimulus-related neural activity in early visual areas is unlikely to provide a general mechanism for explaining differences in perceived duration. PMID:28018282

  6. Type III Radio Burst Duration and SEP Events

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.; Makela, P.; Xie, H.

    2010-01-01

    Long-duration (>15 min), low-frequency (<14 MHz) type III radio bursts have been reported to be indicative of solar energetic particle events. We measured the durations of type III bursts associated with large SEP events of solar cycle 23. The Type III durations are distributed symmetrically at 1 MHz yielding a mean value of approximately 33 min (median = 32 min) for the large SEP events. When the SEP events with ground level enhancement (GLE,) are considered, the distribution is essentially unchanged (mean = 32 min, median = 30 min). To test the importance of type III bursts in indicating SEP events, we considered a set of six type III bursts from the same active region (AR 10588) whose durations fit the "long duration" criterion. We analyzed the coronal mass ejections (CMEs), flares, and type II radio bursts associated with the type III bursts. The CMEs were of similar speeds and the flares are also of similar size and duration. All but one of the type III bursts was not associated with a type II burst in the metric or longer wavelength domains. The burst without type II burst also lacked a solar energetic particle (SEP) event at energies >25 MeV. The 1-MHz duration of the type III burst (28 rein) is near the median value of type III durations found for gradual SEP events and ground level enhancement (GLE) events. Yet, there was no sign of SEP events. On the other hand, two other type III bursts from the same active region had similar duration but accompanied by WAVES type 11 bursts; these bursts were also accompanied by SEP events detected by SOHO/ERNE. This study suggests that the type III burst duration may not be a good indicator of an SEP event, consistent with the statistical study of Cliver and Ling (2009, ApJ ).

  7. The depth dependence of earthquake duration and implications for rupture mechanisms

    USGS Publications Warehouse

    Vidale, J.E.; Houston, H.

    1993-01-01

    THE duration of rupture is a fundamental characteristic of earthquakes, and is important for understanding the mechanics of faulting1,2. The complexity of the seismic source and the incoherence of the high-frequency seismic wavefield often inhibit the identification, location and timing of features in the later part of earthquake rupture. Here we sum many teleseismic records from regional seismic arrays, producing an unusually clear depiction of the earthquake source at short periods by suppressing background noise and coda generated near the receivers. The ending, as well as the beginning, of rupture is clearly identifiable for most earthquakes examined. Measurements of 130 large earthquakes show that near 100 km depth, rupture duration averages 11s when scaled to a moment of 1026 dyn cm; this decreases to 5.5 s at 650 km depth. Models of faulting suggest that duration should be inversely proportional to the shear-wave velocity and the cube root of stress drop. Thus, to explain the observed twofold decrease in duration with depth, stress drops would have to increase by a factor of four, as shear velocity increases with depth by only about 20%. However, observed stress drops show no strong trend with depth3,4, suggesting that the faulting process changes with depth.

  8. Comparing Eye Tracking with Electrooculography for Measuring Individual Sentence Comprehension Duration

    PubMed Central

    Müller, Jana Annina; Wendt, Dorothea; Kollmeier, Birger; Brand, Thomas

    2016-01-01

    The aim of this study was to validate a procedure for performing the audio-visual paradigm introduced by Wendt et al. (2015) with reduced practical challenges. The original paradigm records eye fixations using an eye tracker and calculates the duration of sentence comprehension based on a bootstrap procedure. In order to reduce practical challenges, we first reduced the measurement time by evaluating a smaller measurement set with fewer trials. The results of 16 listeners showed effects comparable to those obtained when testing the original full measurement set on a different collective of listeners. Secondly, we introduced electrooculography as an alternative technique for recording eye movements. The correlation between the results of the two recording techniques (eye tracker and electrooculography) was r = 0.97, indicating that both methods are suitable for estimating the processing duration of individual participants. Similar changes in processing duration arising from sentence complexity were found using the eye tracker and the electrooculography procedure. Thirdly, the time course of eye fixations was estimated with an alternative procedure, growth curve analysis, which is more commonly used in recent studies analyzing eye tracking data. The results of the growth curve analysis were compared with the results of the bootstrap procedure. Both analysis methods show similar processing durations. PMID:27764125

  9. Intensity-Duration Relation in the Bartlett-Lewis Rectangular Pulse Model

    NASA Astrophysics Data System (ADS)

    Ritschel, Christoph; Rust, Henning; Ulbrich, Uwe; Névir, Peter

    2015-04-01

    For several hydrological modelling tasks precipitation time series with a high (sub-daily) resolution are indispensable. This data is, however, not always available and thus replaced by model data. A canonical class of stochastic models for sub-daily precipitation is the class of Poisson cluster processes, e.g. the Bartlett-Lewis rectangular pulse model (BLRPM). The BLRPM has been shown to be able to well reproduce certain characteristics found in observations. Our focus is on intensity-duration relationship which are of particular importance in the context of hydrological modelling. We analyse several high resolution precipitation time series (5min) from Berlin and derive empirical intensity-duration relations for several return levels of intensities (intensity-duration-frequency curves, IDF curves). In a second step, we investigate to what extend the variants of a BLRPM are able to reproduce these relations (i.e., the IDF curves) for different situations (e.g., seasons) and for the various return-levels of intensities. By means of a sensitivity study with the BLRPM, we investigate to what extend the ability to reproduce the intensity-duration relationships is related to certain relations between the model parameters. Such relations are typically useful to reduce the complexity of the model and thus robustify and facilitate parameter estimation.

  10. The impact of coping style on gaze duration.

    PubMed

    Klucken, Tim; Brouwer, Anne-Marie; Chatziastros, Astros; Kagerer, Sabine; Netter, Petra; Hennig, Juergen

    2010-11-15

    The understanding of individual differences in response to threat (e.g., attentional bias) is important to better understand the development of anxiety disorders. Previous studies revealed only a small attentional bias in high-anxious (HA) subjects. One explanation for this finding may be the assumption that all HA-subjects show a constant attentional bias. Current models distinguish HA-subjects depending on their level of tolerance for uncertainty and for arousal. These models assume that only HA-subjects with intolerance for uncertainty but tolerance for arousal ("sensitizers") show an attentional bias, compared to HA-subjects with intolerance for uncertainty and intolerance for arousal ("fluctuating subjects"). Further, it is assumed that repressors (defined as intolerance for arousal but tolerance for uncertainty) would react with avoidance behavior when confronted with threatening stimuli. The present study investigated the influence of coping styles on attentional bias. After an extensive recruiting phase, 36 subjects were classified into three groups (sensitizers, fluctuating, and repressors). All subjects were exposed to presentations of happy and threatening faces, while recording gaze durations with an eye-tracker. The results showed that only sensitizer showed an attentional bias: they gazed longer at the threatening face rather than at the happy face during the first 500 ms. The results support the findings of the relationship between anxiety and attention and extend these by showing variations according to coping styles. The differentiation of subjects according to a multifaceted coping style allows a better prediction of the attentional bias and contributes to an insight into the complex interplay of personality, coping, and behavior.

  11. Duration Adaptation Occurs Across the Sub- and Supra-Second Systems.

    PubMed

    Shima, Shuhei; Murai, Yuki; Hashimoto, Yuki; Yotsumoto, Yuko

    2016-01-01

    After repetitive exposure to a stimulus of relatively short duration, a subsequent stimulus of long duration is perceived as being even longer, and after repetitive exposure to a stimulus of relatively long duration, a subsequent stimulus of short duration is perceived as being even shorter. This phenomenon is called duration adaptation, and has been reported only for sub-second durations. We examined whether duration adaptation also occurs for supra-second durations (Experiment 1) and whether duration adaptation occurs across sub- and supra-second durations (Experiment 2). Duration adaptation occurred not only for sub-second durations, but also for supra-second durations and across sub- and supra-second durations. These results suggest that duration adaptation involves an interval-independent system or two functionally related systems that are associated with both the sub- and supra-second durations.

  12. Factors associated with short sleep duration in adolescents

    PubMed Central

    Felden, Érico Pereira Gomes; Filipin, Douglas; Barbosa, Diego Grasel; Andrade, Rubian Diego; Meyer, Carolina; Louzada, Fernando Mazilli

    2016-01-01

    Abstract Objective: This study aimed to investigate the prevalence and factors associated with short sleep duration in adolescents from Maravilha – Santa Catarina (SC), southern Brazil. Methods: The sample consisted of 516 adolescents aged 10–19 years of both genders. Issues associated with short sleep duration and difficulty falling asleep, chronotype, daytime sleepiness, physical activity, sedentary behavior and weight status were investigated. Results: The prevalence of short sleep duration (<8h on school days) was 53.6%. Adolescents aged 17–19 years showed a 2.05-fold (95%CI: 1.20–3.50) greater prevalence of short sleep duration than those aged 10–12 years. The ones studying in morning and evening shifts had a higher prevalence of short sleep duration compared to those in the afternoon shift. Older age and school shift were the main factors associated with short sleep duration. Conclusions: Adolescents from Maravilha showed high prevalence of short sleep duration, and older adolescents that studied in the morning and evening shifts showed reduced sleep. PMID:26559604

  13. Modulation of tactile duration judgments by emotional pictures

    PubMed Central

    Shi, Zhuanghua; Jia, Lina; Müller, Hermann J.

    2012-01-01

    Judging the duration of emotional stimuli is known to be influenced by their valence and arousal values. However, whether and how perceiving emotion in one modality affects time perception in another modality is still unclear. To investigate this, we compared the influence of different types of emotional pictures—a picture of threat, disgust, or a neutral picture presented at the start of a trial—on temporal bisection judgments of the duration of a subsequently presented vibrotactile stimulus. We found an overestimation of tactile duration following exposure to pictures of threat, but not pictures of disgust (even though these scored equally high on arousal), in a short-range temporal bisection task (range 300/900 ms). Follow-up experiments revealed that this duration lengthening effect was abolished when the range to be bisected was increased (1000/1900 ms). However, duration overestimation was maintained in the short-range bisection task regardless of whether the interval between the visual and tactile events was short or long. This pattern is inconsistent with a general arousal interpretation of duration distortion and suggests that crossmodal linkages in the processing of emotions and emotional regulation are two main factors underlying the manifestation of crossmodal duration modulation. PMID:22654742

  14. Extracting duration information in a picture category decoding task using hidden Markov Models

    NASA Astrophysics Data System (ADS)

    Pfeiffer, Tim; Heinze, Nicolai; Frysch, Robert; Deouell, Leon Y.; Schoenfeld, Mircea A.; Knight, Robert T.; Rose, Georg

    2016-04-01

    Objective. Adapting classifiers for the purpose of brain signal decoding is a major challenge in brain-computer-interface (BCI) research. In a previous study we showed in principle that hidden Markov models (HMM) are a suitable alternative to the well-studied static classifiers. However, since we investigated a rather straightforward task, advantages from modeling of the signal could not be assessed. Approach. Here, we investigate a more complex data set in order to find out to what extent HMMs, as a dynamic classifier, can provide useful additional information. We show for a visual decoding problem that besides category information, HMMs can simultaneously decode picture duration without an additional training required. This decoding is based on a strong correlation that we found between picture duration and the behavior of the Viterbi paths. Main results. Decoding accuracies of up to 80% could be obtained for category and duration decoding with a single classifier trained on category information only. Significance. The extraction of multiple types of information using a single classifier enables the processing of more complex problems, while preserving good training results even on small databases. Therefore, it provides a convenient framework for online real-life BCI utilizations.

  15. Extracting duration information in a picture category decoding task using hidden Markov Models

    PubMed Central

    Pfeiffer, Tim; Heinze, Nicolai; Frysch, Robert; Deouell, Leon Y; Schoenfeld, Mircea A; Knight, Robert T; Rose, Georg

    2016-01-01

    Objective Adapting classifiers for the purpose of brain signal decoding is a major challenge in brain–computer-interface (BCI) research. In a previous study we showed in principle that hidden Markov models (HMM) are a suitable alternative to the well-studied static classifiers. However, since we investigated a rather straightforward task, advantages from modeling of the signal could not be assessed. Approach Here, we investigate a more complex data set in order to find out to what extent HMMs, as a dynamic classifier, can provide useful additional information. We show for a visual decoding problem that besides category information, HMMs can simultaneously decode picture duration without an additional training required. This decoding is based on a strong correlation that we found between picture duration and the behavior of the Viterbi paths. Main results Decoding accuracies of up to 80% could be obtained for category and duration decoding with a single classifier trained on category information only. Significance The extraction of multiple types of information using a single classifier enables the processing of more complex problems, while preserving good training results even on small databases. Therefore, it provides a convenient framework for online real-life BCI utilizations. PMID:26859831

  16. Forecasting the duration of volcanic eruptions: an empirical probabilistic model

    NASA Astrophysics Data System (ADS)

    Gunn, L. S.; Blake, S.; Jones, M. C.; Rymer, H.

    2014-01-01

    The ability to forecast future volcanic eruption durations would greatly benefit emergency response planning prior to and during a volcanic crises. This paper introduces a probabilistic model to forecast the duration of future and on-going eruptions. The model fits theoretical distributions to observed duration data and relies on past eruptions being a good indicator of future activity. A dataset of historical Mt. Etna flank eruptions is presented and used to demonstrate the model. The data have been compiled through critical examination of existing literature along with careful consideration of uncertainties on reported eruption start and end dates between the years 1300 AD and 2010. Data following 1600 is considered to be reliable and free of reporting biases. The distribution of eruption duration between the years 1600 and 1669 is found to be statistically different from that following it and the forecasting model is run on two datasets of Mt. Etna flank eruption durations: 1600-2010 and 1670-2010. Each dataset is modelled using a log-logistic distribution with parameter values found by maximum likelihood estimation. Survivor function statistics are applied to the model distributions to forecast (a) the probability of an eruption exceeding a given duration, (b) the probability of an eruption that has already lasted a particular number of days exceeding a given total duration and (c) the duration with a given probability of being exceeded. Results show that excluding the 1600-1670 data has little effect on the forecasting model result, especially where short durations are involved. By assigning the terms `likely' and `unlikely' to probabilities of 66 % or more and 33 % or less, respectively, the forecasting model based on the 1600-2010 dataset indicates that a future flank eruption on Mt. Etna would be likely to exceed 20 days (± 7 days) but unlikely to exceed 86 days (± 29 days). This approach can easily be adapted for use on other highly active, well

  17. Sleep Duration and Area-Level Deprivation in Twins

    PubMed Central

    Watson, Nathaniel F.; Horn, Erin; Duncan, Glen E.; Buchwald, Dedra; Vitiello, Michael V.; Turkheimer, Eric

    2016-01-01

    Study Objectives: We used quantitative genetic models to assess whether area-level deprivation as indicated by the Singh Index predicts shorter sleep duration and modifies its underlying genetic and environmental contributions. Methods: Participants were 4,218 adult twin pairs (2,377 monozygotic and 1,841 dizygotic) from the University of Washington Twin Registry. Participants self-reported habitual sleep duration. The Singh Index was determined by linking geocoding addresses to 17 indicators at the census-tract level using data from Census of Washington State and Census Tract Cartographic Boundary Files from 2000 and 2010. Data were analyzed using univariate and bivariate genetic decomposition and quantitative genetic interaction models that assessed A (additive genetics), C (common environment), and E (unique environment) main effects of the Singh Index on sleep duration and allowed the magnitude of residual ACE variance components in sleep duration to vary with the Index. Results: The sample had a mean age of 38.2 y (standard deviation [SD] = 18), and was predominantly female (62%) and Caucasian (91%). Mean sleep duration was 7.38 h (SD = 1.20) and the mean Singh Index score was 0.00 (SD = 0.89). The heritability of sleep duration was 39% and the Singh Index was 12%. The uncontrolled phenotypic regression of sleep duration on the Singh Index showed a significant negative relationship between area-level deprivation and sleep length (b = −0.080, P < 0.001). Every 1 SD in Singh Index was associated with a ∼4.5 min change in sleep duration. For the quasi-causal bivariate model, there was a significant main effect of E (b0E = −0.063; standard error [SE] = 0.30; P < 0.05). Residual variance components unique to sleep duration were significant for both A (b0Au = 0.734; SE = 0.020; P < 0.001) and E (b0Eu = 0.934; SE = 0.013; P < 0.001). Conclusions: Area-level deprivation has a quasi-causal association with sleep duration, with greater deprivation being related to

  18. New approach of financial volatility duration dynamics by stochastic finite-range interacting voter system

    NASA Astrophysics Data System (ADS)

    Wang, Guochao; Wang, Jun

    2017-01-01

    We make an approach on investigating the fluctuation behaviors of financial volatility duration dynamics. A new concept of volatility two-component range intensity (VTRI) is developed, which constitutes the maximal variation range of volatility intensity and shortest passage time of duration, and can quantify the investment risk in financial markets. In an attempt to study and describe the nonlinear complex properties of VTRI, a random agent-based financial price model is developed by the finite-range interacting biased voter system. The autocorrelation behaviors and the power-law scaling behaviors of return time series and VTRI series are investigated. Then, the complexity of VTRI series of the real markets and the proposed model is analyzed by Fuzzy entropy (FuzzyEn) and Lempel-Ziv complexity. In this process, we apply the cross-Fuzzy entropy (C-FuzzyEn) to study the asynchrony of pairs of VTRI series. The empirical results reveal that the proposed model has the similar complex behaviors with the actual markets and indicate that the proposed stock VTRI series analysis and the financial model are meaningful and feasible to some extent.

  19. Psychological, psychiatric, and interpersonal aspects of long-duration space missions.

    PubMed

    Kanas, N

    1990-01-01

    America's future in space calls for manned missions that are of long duration and increasing complexity. Under these conditions, psychological and interpersonal stressors will take on added importance in affecting the safely of the crew and the outcome of the mission. Through an analysis of reports from manned American and Soviet space missions and Earth-bound simulations, several psychological, psychiatric, and interpersonal issues can be identified that could affect the success of the space station and other long-duration space ventures. Psychological issues include sleep problems, alteration in time sense, demographic effects, career motivation, transcendent experiences, homesickness, and alteration in perceptual sensitivities. Psychiatric issues include anxiety, depression, and psychosis, psychosomatic symptoms, emotional problems related to the stage of the mission, and postflight personality changes. Interpersonal issues include interpersonal tension, decreased cohesiveness over time, need for privacy, and task vs emotional leadership. Steps can be taken to minimize the impact of these issues, both before and during the mission.

  20. Bayesian Hierarchical Duration Model for Repeated Events : An Application to Behavioral Observations

    PubMed Central

    Dagne, Getachew A.; Snyder, James

    2009-01-01

    This paper presents a continuous-time Bayesian model for analyzing durations of behavior displays in social interactions. Duration data of social interactions are often complex because of repeated behaviors (events) at individual or group (e.g., dyad) level, multiple behaviors (multistates), and several choices of exit from a current event (competing risks). A multilevel, multistate model is proposed to adequately characterize the behavioral processes. The model incorporates dyad-specific and transition-specific random effects to account for heterogeneity among dyads and interdependence among competing risks. The proposed method is applied to child-parent observational data derived from the School Transitions Project to assess the relation of emotional expression in child-parent interaction to risk for early and persisting child conduct problems. PMID:20209032