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  1. Temporary epicardial left ventricular and biventricular pacing improves cardiac output after cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    García-Bengochea Jose B

    2012-10-01

    Full Text Available Abstract Background To evaluate, with different pacing modes, acute changes in left ventricular systolic function, obtained by continuous cardiac output thermodilution in various subsets of patients undergoing cardiopulmonary bypass surgery. Increments of mean arterial pressure and cardiac output were considered the end point. Methods Fifty cases electively submitted to cardiac surgery were analyzed. Isolated valve surgery 62%, coronary revascularization 30% and 8% mixed disease. Left ventricular ejection fraction was preserved in 50%,36% had moderate depression,(EF 36%-50% whereas 14% had severe depression (EF  Results Right atrium-right ventricular pacing, decreased significantly mean arterial pressure and cardiac output (2.3% in the overall population and in the subgroups studied. Right atrium-left ventricle, increased mean arterial pressure and cardiac output in 79% of patients and yielded cardiac output increments of 7.5% (0.40 l/m in the low ejection fraction subgroup and 7.3% (0.43 l/m in the left bundle branch block subset. In atrial fibrillation patients, left ventricular and biventricular pacing produced a significant increase in cardiac output 8.5% (0.39 l/min and 11.6% (0.53 l/min respectively. The dP/dt max increased significantly with both modes (p = 0.021,p = 0.028. Conclusion Right atrial-right ventricular pacing generated adverse hemodynamic effects. Right atrium-left ventricular pacing produced significant CO improvement particularly in cases with depressed ventricular function and left bundle branch block. The greatest increments were observed with left ventricular or biventricular pacing in atrial fibrillation with depressed ejection fraction.

  2. Impact of pacing modality and biventricular pacing on cardiac output and coronary conduit flow in the post-cardiotomy patient.

    LENUS (Irish Health Repository)

    Healy, David G

    2012-02-03

    We have previously demonstrated the role of univentricular pacing modalities in influencing coronary conduit flow in the immediate post-operative period in the cardiac surgery patient. We wanted to determine the mechanism of this improved coronary conduit and, in addition, to explore the possible benefits with biventricular pacing. Sixteen patients undergoing first time elective coronary artery bypass grafting who required pacing following surgery were recruited. Comparison of cardiac output and coronary conduit flow was performed between VVI and DDD pacing with a single right ventricular lead and biventricular pacing lead placement. Cardiac output was measured using arterial pulse waveform analysis while conduit flow was measured using ultrasonic transit time methodology. Cardiac output was greatest with DDD pacing using right ventricular lead placement only [DDD-univentricular 5.42 l (0.7), DDD-biventricular 5.33 l (0.8), VVI-univentricular 4.71 l (0.8), VVI-biventricular 4.68 l (0.6)]. DDD-univentricular pacing was significantly better than VVI-univentricular (P=0.023) and VVI-biventricular pacing (P=0.001) but there was no significant advantage to DDD-biventricular pacing (P=0.45). In relation to coronary conduit flow, DDD pacing again had the highest flow [DDD-univentricular 55 ml\\/min (24), DDD-biventricular 52 ml\\/min (25), VVI-univentricular 47 ml\\/min (23), VVI-biventricular 50 ml\\/min (26)]. DDD-univentricular pacing was significantly better than VVI-univentricular (P=0.006) pacing but not significantly different to VVI-biventricular pacing (P=0.109) or DDD-biventricular pacing (P=0.171). Pacing with a DDD modality offers the optimal coronary conduit flow by maximising cardiac output. Biventricular lead placement offered no significant benefit to coronary conduit flow or cardiac output.

  3. Successful treatment with biventricular pacing in a patient with hypertrophic obstructive cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    HE Ji-qiang; JIANG Teng-yong; WANG Yun-long; WANG Yan; L(U) Shu-zheng

    2011-01-01

    We report the effects of biventricular pacing in a patient with hypertrophic obstructive cardiomyopathy (HOCM) refractory to medical therapy. A 58-year-old man with HOCM had suffered from dyspnea,chest pain and palpitation for 5 years. Cardiac catheterization showed a left ventricular outflow tract (LVOT) gradient of 80 mmHg. He refused septal myomectomy and the septal ablation was not available. Based on intraoperative pressure measurements,he was implanted with biventricular pacing and LVOT gradient decreased to 10 mmHg. During the follow-up period of 6 months, the patient's symptoms were markedly improved. Biventricular pacing may be an alternative therapy for patients with HOCM.

  4. Usefulness of biventricular pacing to improve cardiac symptoms, exercise capacity and sympathetic nerve activity in patients with moderate to severe chronic heart failure

    International Nuclear Information System (INIS)

    Although cardiac resynchronization using biventricular pacing (BVP) results in significant clinical improvement in patients with chronic heart failure (CHF), there is no evidence of improvement in sympathetic nerve activity (SNA). Eighteen patients with CHF (dilated cardiomyopathy/ischemic cardiomyopathy=14/4) and left ventricular (LV) ejection fraction 160 ms and dyssynchronous LV wall motion were classified into 2 groups based on the findings of 99mTc-methoxyisobutyl isonitrile (MIBI) quantitative gated single-photon emission computed tomography (SPECT) (QGS). Resynchronization was considered to be present when the difference between the QGS frame number for end-systole for the LV septal and lateral walls (dyssynchrony index) disappeared. Group A achieved resynchronization after BVP, but not Group B. In group A, New York Heart Association functional class (p=0.0002), specific activity scale (p=0.0001), total defect score (p123I-metaiodobenzylguanidine imaging (p<0.05) were significantly improved after resynchronization. However, there was no significant change in group B. Cardiac resynchronization after BVP can improve cardiac symptoms, exercise capacity, and SNA in patients with moderate to severe CHF. (author)

  5. Hemodynamic aspects of biventricular pacing in heart failure

    OpenAIRE

    Ståhlberg, Marcus

    2010-01-01

    Background and aims Biventricular pacing or cardiac resynchronization therapy (CRT) is an established treatment option for selected heart failure (HF) patients. We aimed at evaluating acute and longer-term hemodynamic effects of different pacemaker programmings in CRT patients. For the latter purpose, 10 CRT patients also received an implantable hemodynamic monitor (IHM), allowing for long-term hemodynamic monitoring during ambulatory periods. Study I The hemodynamic ...

  6. Comparison of permanent left ventricular and biventricular pacing in patients with heart failure and chronic atrial fibrillation: prospective haemodynamic study

    OpenAIRE

    Garrigue, S; Bordachar, P.; Reuter, S.; Jaïs, P.; Kobeissi, A; Gaggini, G; Haïssaguerre, M; Clementy, J

    2002-01-01

    Objective: To compare clinical and haemodynamic variables between left ventricular and biventricular pacing in patients with severe heart failure; and to analyse haemodynamic changes during daily life and maximum exercise during chronic left ventricular and biventricular pacing.

  7. Biventricular stimulation to prevent cardiac desynchronization: rationale, design, and endpoints of the 'Biventricular Pacing for Atrioventricular Block to Prevent Cardiac Desynchronization (BioPace)' study.

    Science.gov (United States)

    Funck, Reinhard C; Blanc, Jean-Jacques; Mueller, Hans-Helge; Schade-Brittinger, Carmen; Bailleul, Christophe; Maisch, Bernhard

    2006-08-01

    Despite the deleterious effects of cardiac dyssynchrony and the positive effects of cardiac resynchronization therapy, patients with high-degree atrioventricular block continue to receive desynchronizing right ventricular (RV) pacing systems. Although it is unclear whether the negative effects of RV pacing and left bundle branch block (LBBB) are comparable, and whether they depend on the presence and the degree of structural heart disease, one may hypothesize that RV pacing may have similar effects to LBBB. In the BioPace trial, the long-term effects of RV pacing vs. biventricular pacing will be prospectively compared in 1200 pacemaker patients with high likelihood of mostly paced ventricular events, regardless of whether in sinus rhythm or in atrial fibrillation (AF). After echocardiographic examination of left ventricular (LV) function, patients will be randomly assigned to the implantation of an RV vs. a biventricular pacing system and followed for up to 5 years. Primary study endpoints are survival, quality of life (QoL), and the distance covered in a 6-min hall walk (6-MHW) at 24 months after implantation. Secondary endpoints are QoL and the 6-MHW result at 12 months after implantation, hospitalization rate, LV dimensions, LV ejection fraction, and the development of chronic AF and other adverse events. PMID:16864616

  8. Acute contractile recovery extent during biventricular pacing is not associated with follow-up in patients undergoing resynchronization

    OpenAIRE

    Federica DeVecchi; Emanuela Facchini; Anna Degiovanni; Chiara Sartori; Chiara Cavallino; Matteo Santagostino; Virginia Di Ruocco; Andrea Magnani; Eraldo Occhetta; Paolo Nicola Marino

    2016-01-01

    Background: It has been reported that contractility, as assessed using dobutamine infusion, is independently associated with reverse remodeling after CRT. Controversy, however, exists about the capacity of this approach to predict a long-term clinical response. This study's purpose was to assess whether long-term CRT clinical effects can be predicted according to acute inotropic response induced by biventricular stimulation (CRT on), as compared with AAI–VVI right stimulation pacing mode (CRT...

  9. Tissue Doppler echocardiography and biventricular pacing in heart failure: Patient selection, procedural guidance, follow-up, quantification of success

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    Baumann Gert

    2004-09-01

    Full Text Available Abstract Asynchronous myocardial contraction in heart failure is associated with poor prognosis. Resynchronization can be achieved by biventricular pacing (BVP, which leads to clinical improvement and reverse remodeling. However, there is a substantial subset of patients with wide QRS complexes in the electrocardiogram that does not improve despite BVP. QRS width does not predict benefit of BVP and only correlates weakly with echocardiographically determined myocardial asynchrony. Determination of asynchrony by Tissue Doppler echocardiography seems to be the best predictor for improvement after BVP, although no consensus on the optimal method to assess asynchrony has been achieved yet. Our own preliminary results show the usefulness of Tissue Doppler Imaging and Tissue Synchronization Imaging to document acute and sustained improvement after BVP. To date, all studies evaluating Tissue Doppler in BVP were performed retrospectively and no prospective studies with patient selection for BVP according to echocardiographic criteria of asynchrony were published yet. We believe that these new echocardiographic tools will help to prospectively select patients for BVP, help to guide implantation and to optimize device programming.

  10. Reverse left ventricular remodeling is more likely in non ischemic cardiomyopathy patients upgraded to biventricular stimulation after chronic right ventricular pacing

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    Morales Maria-Aurora

    2011-12-01

    Full Text Available Abstract Background Chronic right ventricular (RV apical pacing may lead to left ventricular (LV dyssynchrony and LV dysfunction. In heart failure due to RV pacing, upgrading to biventricular stimulation (CRT can improve NYHA Class and LV function. A proportion of patients do not respond to upgrading. Aim was to assess whether etiology of LV dysfunction accounts for responses to CRT in RV-paced patients. Methods Sixty-two patients treated by CRT, under RV pacing from 50.2 ± 5.4 months, were studied. Cause of LV dysfunction was non-ischemic (NIC in 28 and ischemic cardiomyopathy (IC in 34 patients. Clinical and conventional echocardiographic parameters were available within 1 month before RV pacing, within 1 month before CRT and at 12 ± 2 months of follow-up (FU. Results Decreased LVEF (from 37.0 ± 8.8 to 25.6 ± 6.1%, p 10% decrease in LVESD was observed in 24 patients: 5 with IC, 19 with NIC (p 10% decrease in LVESD remained highly significant (p Conclusions CRT improves functional class even after long-lasting pacing. Reverse remodeling is evident in a small population, more likely with NIC.

  11. The association between biventricular pacing and cardiac resynchronization therapy-defibrillator efficacy when compared with implantable cardioverter defibrillator on outcomes and reverse remodelling

    DEFF Research Database (Denmark)

    Ruwald, Anne-Christine; Kutyifa, Valentina; Ruwald, Martin H;

    2015-01-01

    AIMS: Previous studies on biventricular (BIV) pacing and cardiac resynchronization therapy-defibrillator (CRT-D) efficacy have used arbitrarily chosen BIV pacing percentages, and no study has employed implantable cardioverter defibrillator (ICD) patients as a control group. METHODS AND RESULTS...

  12. Association between frequency of atrial and ventricular ectopic beats and biventricular pacing percentage and outcomes in patients with cardiac resynchronization therapy

    DEFF Research Database (Denmark)

    Ruwald, Martin H; Mittal, Suneet; Ruwald, Anne-Christine;

    2014-01-01

    -defibrillator device with data available on biventricular pacing percentage and pre-implantation 24-h Holter recordings were included. Using logistic regression, we estimated the influence of ectopic beats on the percentage of biventricular pacing. Reverse remodeling was measured as reductions in atrial and left...... ventricular end-systolic volumes (LVESV) at 1 year. Cox models were used to assess the influence of ectopic beats on the outcomes of heart failure (HF) or death, ventricular tachyarrhythmias (VTAs), and death. RESULTS: In the pre-implantation Holter recording, ectopic beats accounted for a mean 3.2 ± 5.5% of...

  13. Fitness in chronic heart failure: effects of exercise training and of biventricular pacing

    OpenAIRE

    Gademan, Maaike

    2009-01-01

    In CHF patients exercise capacity is decreased (low physical fitness). The degree of exercise intolerance in CHF is paralleled by an increased mortality, moreover, several studies suggest that increasing exercise capacity in CHF improves prognosis. Therefore, improving exercise capacity is one of the major issues in CHF-related treatment. Besides this decreased exercise capacity CHF patients also have a low autonomic fitness (high neurohumoral activation and a low baroreflex sensitivity (BRS)...

  14. TEE-guided left ventricular epicardial pacing lead placement for cardiac resynchronization therapy

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    Rajesh Chand Arya

    2012-01-01

    Full Text Available Biventricular pacing has demonstrated improvement in cardiac functions in treating congestive cardiac failure patients. Recent trials have proven the clinical and functional benefits of cardiac resynchronization therapy in severe heart failure and intraventricular cardiac delays, mainly left bundle branch block. Biventricular pacing improves the exercise tolerance, quality of life, systolic heart function, reduces hospitalization and slows progression of the disease. A 54-year-old lady, a known case of dilated cardiomyopathy, was on biventricular pacing since 2 years. She presented in emergency with sudden deterioration of dyspnea to NYHA class III/IV. When investigated, the coronary sinus lead was found displaced; thus, left ventricle (LV was not getting paced. After multiple failures to reposition the coronary sinus lead, it was decided to surgically place the epicardial lead for LV pacing under general anesthesia. Lateral thoracotomy was done and LV pacing lead was placed at different sites with simultaneous monitoring of cardiac output (CO and stroke volume (SV by transesophageal echocardiography (TEE. Baseline CO and SV were 1.9 l/min and 19.48 ml respectively and increased at different sites of pacing at LV, the best CO and SV were 4.2 l/min and 42.39 ml respectively on lateral surface. Intraoperative TEE can calculate beat to beat stroke volume and thus CO and helps to choose optimal site for placement of epicardial pacing lead.

  15. Temporary epicardial cardiac resynchronisation versus conventional right ventricular pacing after cardiac surgery: study protocol for a randomised control trial

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    Russell Stuart J

    2012-02-01

    Full Text Available Abstract Background Heart failure patients with stable angina, acute coronary syndromes and valvular heart disease may benefit from revascularisation and/or valve surgery. However, the mortality rate is increased- 5-30%. Biventricular pacing using temporary epicardial wires after surgery is a potential mechanism to improve cardiac function and clinical endpoints. Method/design A multi-centred, prospective, randomised, single-blinded, intervention-control trial of temporary biventricular pacing versus standard pacing. Patients with ischaemic cardiomyopathy, valvular heart disease or both, an ejection fraction ≤ 35% and a conventional indication for cardiac surgery will be recruited from 2 cardiac centres. Baseline investigations will include: an electrocardiogram to confirm sinus rhythm and measure QRS duration; echocardiogram to evaluate left ventricular function and markers of mechanical dyssynchrony; dobutamine echocardiogram for viability and blood tests for renal function and biomarkers of myocardial injury- troponin T and brain naturetic peptide. Blood tests will be repeated at 18, 48 and 72 hours. The principal exclusions will be subjects with permanent atrial arrhythmias, permanent pacemakers, infective endocarditis or end-stage renal disease. After surgery, temporary pacing wires will be attached to the postero-lateral wall of the left ventricle, the right atrium and right ventricle and connected to a triple chamber temporary pacemaker. Subjects will be randomised to receive either temporary biventricular pacing or standard pacing (atrial inhibited pacing or atrial-synchronous right ventricular pacing for 48 hours. The primary endpoint will be the duration of level 3 care. In brief, this is the requirement for invasive ventilation, multi-organ support or more than one inotrope/vasoconstrictor. Haemodynamic studies will be performed at baseline, 6, 18 and 24 hours after surgery using a pulmonary arterial catheter. Measurements will be

  16. [The best of cardiac pacing in 1999].

    Science.gov (United States)

    Deharo, J C

    2000-01-01

    Since the first clinical application to man forty years ago, for the treatment of bradycardia, cardiac pacing has been the object of continuous technological innovation in parallel with those in electronics and computerisation. However, independently of these expected advances, there has been a surprising widening of the field of application of pacing into those of haemodynamics and rhythmology. The recent publication of the long-term results of the Pacing in Cardiomyopathy (PIC) study confirmed the sustained decrease of intraventricular pressure gradient, of NYHA functional stage and improved quality of life of patients with hypertrophic obstructive cardiomyopathy paced in the DDD mode. The investigators also underlined the placebo effect of the pacemaker. The decrease in risk of sudden death and the reduction in ventricular remodelling have not been demonstrated yet. More recently, biventricular pacing has been proposed for the treatment of dilated cardiomyopathy and a French study showed a long-term improvement in NYHA stage and effort capacity. Several prospective randomised trials are under way to validate this indication. Acute haemodynamic evaluations have confirmed the efficacy of biventricular stimulation but also underline the value of left ventricular pacing alone. The effects on mortality, the selection of patients and the optimal configuration of pacing remain to be defined. In the field of prevention of atrial arrhythmias, the results of the multicenter SYNBIAPACE study, investigating biatrial pacing in patients with interatrial conduction defects, only showed a tendency to an increase in the delay before recurrence of atrial fibrillation. The value of the memory functions of pacemakers and the algorithms of prevention of atrial arrhythmias are still under investigation. Haemodynamic transducers have been introduced in some recent pacemakers to assess myocardial contractility and have applications in the evaluation of different pacing modes and in the

  17. Ultra-High-Frequency ECG Parameter as a New Marker for Prediction of Biventricular Pacemaker Responders

    Czech Academy of Sciences Publication Activity Database

    Reichlova, T.; Jurák, Pavel; Halámek, Josef; Plešinger, Filip; Lipoldová, J.; Novák, M.; Leinveber, P.

    Brno: Society for Medical Innovation and Technology, 2015. s. 63. [SMIT 2015. International Conference of the Society for Medical Innovation and Technology/27./. 10.09.2015-12.09.2015, Brno] Institutional support: RVO:68081731 Keywords : Ultra high frequency ECG * biventricular pacing * ventricular dyssynchrony * cardiac resynchronization therapy Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  18. A fast-start pacing strategy speeds pulmonary oxygen uptake kinetics and improves supramaximal running performance.

    Directory of Open Access Journals (Sweden)

    Tiago Turnes

    Full Text Available The focus of the present study was to investigate the effects of a fast-start pacing strategy on running performance and pulmonary oxygen uptake (VO2 kinetics at the upper boundary of the severe-intensity domain. Eleven active male participants (28±10 years, 70±5 kg, 176±6 cm, 57±4 mL/kg/min visited the laboratory for a series of tests that were performed until exhaustion: 1 an incremental test; 2 three laboratory test sessions performed at 95, 100 and 110% of the maximal aerobic speed; 3 two to four constant speed tests for the determination of the highest constant speed (HS that still allowed achieving maximal oxygen uptake; and 4 an exercise based on the HS using a higher initial speed followed by a subsequent decrease. To predict equalized performance values for the constant pace, the relationship between time and distance/speed through log-log modelling was used. When a fast-start was utilized, subjects were able to cover a greater distance in a performance of similar duration in comparison with a constant-pace performance (constant pace: 670 m±22%; fast-start: 683 m±22%; P = 0.029; subjects also demonstrated a higher exercise tolerance at a similar average speed when compared with constant-pace performance (constant pace: 114 s±30%; fast-start: 125 s±26%; P = 0.037. Moreover, the mean VO2 response time was reduced after a fast start (constant pace: 22.2 s±28%; fast-start: 19.3 s±29%; P = 0.025. In conclusion, middle-distance running performances with a duration of 2-3 min are improved and VO2 response time is faster when a fast-start is adopted.

  19. Biventricular mechanical support devices - clinical perspectives.

    Science.gov (United States)

    Shehab, Sajad; Newton, Phillip J; Allida, Sabine M; Jansz, Paul C; Hayward, Christopher S

    2016-04-01

    Cardiac transplantation remains the optimal treatment for end stage heart failure in selected patients. However, the shortage of donor hearts, rigorous eligibility criteria and long waiting lists have increased the demand for alternative treatment strategies such as mechanical circulatory support. While many patients are adequately supported with left ventricular assist devices, frequently there is right heart failure or involvement of the right ventricle, requiring biventricular support. Pulsatile flow biventricular devices and total artificial hearts approved for temporary biventricular support have limitations including size, high rates of adverse events and restricted mobility which makes them unsuitable for long term support. A number of centres have reported dual continuous flow left ventricular assist devices as a means of supporting the left and right heart. This review will summarise the literature on the outcomes and complications from current biventricular support devices and assess the role of dual continuous flow VAD therapy, and the new continuous flow total heart replacement devices. PMID:26894825

  20. Temporary pacing

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    L.J. Workman

    1983-09-01

    Full Text Available Artificial cardiac pacing, the use of electrical stimuli to cause contraction of heart muscle, is a sophisticated therapeutic and diagnostic tool. Its rapid technologic improvement since first developed in the late 1930’s by Hyman, has made it possible not only to avoid certain cases of death due to heart block, but also to extend and improve the quality of life. Pacemaker therapy is generally used to treat heart rate or rhythm disturbances, being either tachy- or bradyarrhythmias that produce a detrimental drop in cardiac output. Of the many different types of pacemakers and electrodes currently available, ventricular demand pacing is the most commonly used.

  1. Efficacy of paced breathing for insomnia: enhances vagal activity and improves sleep quality.

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    Tsai, H J; Kuo, Terry B J; Lee, Guo-She; Yang, Cheryl C H

    2015-03-01

    Fourteen self-reported insomniacs (SRI) and 14 good sleepers (GS) had their cardiac neuronal activity assessed by heart rate variability (HRV) under controlled respiration at a slow frequency rate of 0.1 Hz, and a forced rate of 0.2 Hz during daytime rest. Nighttime sleep was measured by polysomnography. The SRI showed depressed high frequency power of HRV compared to the GS. An increased total power of HRV was observed among the SRI during slow, paced breathing compared with spontaneous breathing and 0.2 Hz. Sleep onset latency, number of awakenings, and awakening time during sleep were decreased and sleep efficiency was increased if SRI practiced slow, paced breathing exercises for 20 min before going to sleep. Our results indicate that there is autonomic dysfunction among insomniacs, especially in relation to vagal activity; however, this decreased vagal activity can be facilitated by practicing slow, paced breathing, thereby improving sleep quality. PMID:25234581

  2. "U-Pace" Instruction: Improving Student Success by Integrating Content Mastery and Amplified Assistance

    Science.gov (United States)

    Reddy, Diane M.; Pfeiffer, Heidi M.; Fleming, Raymond; Ports, Katie A.; Pedrick, Laura E.; Barnack-Tavlaris, Jessica L.; Jirovec, Danielle L.; Helion, Alicia M.; Swain, Rodney A.

    2013-01-01

    "U-Pace," an instructional intervention, has potential for widespread implementation because student behavior recorded in any learning management system is used by "U-Pace" instructors to tailor coaching of student learning based on students' strengths and motivations. "U-Pace" utilizes an online learning…

  3. Coronary grafts flow and cardiac pacing modalities: how to improve perioperative myocardial perfusion.

    LENUS (Irish Health Repository)

    D'Ancona, Giuseppe

    2012-02-03

    OBJECTIVE: Aim of this study was to investigate modifications of coronary grafts flow during different pacing modalities after CABG. MATERIALS AND METHODS: Two separate prospective studies were conducted in patients undergoing CABG and requiring intraoperative epicardial pacing. In a first study (22 patients) coronary grafts flows were measured during dual chamber pacing (DDD) and during ventricular pacing (VVI). In a second study (10 patients) flows were measured during DDD pacing at different atrio-ventricular (A-V) delay periods. A-V delay was adjusted in 25 ms increments from 25 to 250 ms and flow measurements were performed for each A-V delay increment. A transit time flowmeter was used for the measurements. RESULTS: An average of 3.4 grafts\\/patient were performed. In the first study, average coronary graft flow was 47.4+\\/-20.8 ml\\/min during DDD pacing and 41.8+\\/-18.2 ml\\/min during VVI pacing (P = 0.0004). Furthermore average systolic pressure was 94.3+\\/-10.1 mmHg during DDD pacing and 89.6+\\/-12.2 mmHg during VVV pacing (P = 0.0007). No significant differences in diastolic pressure were recorded during the two different pacing modalities. In the second study, maximal flows were achieved during DDD pacing with an A-V delay of 175 ms (54+\\/-9.6 ml\\/min) and minimal flows were detected at 25 ms A-V delay (38.1+\\/-4.7 ml\\/min) (P=ns). No significant differences in systolic or diastolic blood pressure were noticed during the different A-V delays. CONCLUSION: Grafts flowmetry provides an extra tool to direct supportive measures such as cardiac pacing after CABG. DDD mode with A-V delay around 175 ms. should be preferred to allow for maximal myocardial perfusion via the grafts.

  4. Speckle-tracking echocardiography elucidates the effect of pacing site on left ventricular synchronization in the normal and infarcted rat myocardium.

    Directory of Open Access Journals (Sweden)

    Michal Mor

    Full Text Available BACKGROUND: Right ventricular (RV pacing generates regional disparities in electrical activation and mechanical function (ventricular dyssynchrony. In contrast, left ventricular (LV or biventricular (BIV pacing can improve cardiac efficiency in the setting of ventricular dyssynchrony, constituting the rationale for cardiac resynchronization therapy (CRT. Animal models of ventricular dyssynchrony and CRT currently relay on large mammals which are expensive and not readily available to most researchers. We developed a methodology for double-site epicardial pacing in conscious rats. Here, following post-operative recovery, we compared the effects of various pacing modes on LV dyssynchrony in normal rats and in rats with ischemic cardiomyopathy. METHODS: Two bipolar electrodes were implanted in rats as follows: Group A (n = 6 right atrial (RA and RV sites; Group B (n = 7 RV and LV sites; Group C (n = 8 as in group B in combination with left coronary artery ligation. Electrodes were exteriorized through the back. Following post-operative recovery, two-dimensional transthoracic echocardiography was performed during pacing through the different electrodes. Segmental systolic circumferential strain (Ecc was used to evaluate LV dyssynchrony. RESULTS: In normal rats, RV pacing induced marked LV dyssynchrony compared to RA pacing or sinus rhythm, as measured by the standard deviation (SD of segmental time to peak Ecc, SD of peak Ecc, and the average delay between opposing ventricular segments. LV pacing and, to a greater extend BIV pacing diminished the LV dyssynchrony compared to RV pacing. In rats with extensive MI, the effects of LV and BIV pacing were markedly attenuated, and the response of individual animals was variable. CONCLUSIONS: Rodent cardiac pacing mimics important features seen in humans. This model may be developed as a simple new tool to study the pathophysiology of ventricular dyssynchrony and CRT.

  5. HeartWare HVAD for Biventricular Support in Children and Adolescents: The Stanford Experience.

    Science.gov (United States)

    Stein, Mary Lyn; Yeh, Justin; Reinhartz, Olaf; Rosenthal, David N; Kaufman, Beth D; Almond, Chris S; Hollander, Seth A; Maeda, Katsuhide

    2016-01-01

    Despite increasing use of mechanical circulatory support in children, experience with biventricular device implantation remains limited. We describe our experience using the HeartWare HVAD to provide biventricular support to three patients and compare these patients with five patients supported with HeartWare left ventricular assist device (LVAD). At the end of the study period, all three biventricular assist device (BiVAD) patients had been transplanted and were alive. LVAD patients were out of bed and ambulating a median of 10.5 days postimplantation. The BiVAD patients were out of bed a median of 31 days postimplantation. Pediatric patients with both left ventricular and biventricular heart failure can be successfully bridged to transplantation with the HeartWare HVAD. Rapid improvement in functional status following HVAD implantation for isolated left ventricular support is seen. Patients supported with BiVAD also demonstrate functional recovery, albeit more modestly. In the absence of infection, systemic inflammatory response raises concern for inadequate support. PMID:26919182

  6. Pace yourself: Improving time-saving judgments when increasing activity speed

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    Eyal Peer

    2013-03-01

    Full Text Available The time-saving bias describes people's tendency to misestimate the time they can save by increasing the speed in which they perform an activity such as driving or completing a task. People typically underestimate time saved when increasing from a low speed and overestimate time saved when increasing from an already high speed. We suggest that this bias is the result of people's failure to recognize the curvilinear relationship between increasing speed and reducing activity time: As initial speed rises, the same speed increases will yield smaller reductions in time. We explore a new technique to de-bias these faulty estimations: converting measurements of speed to a pace measure (e.g., minutes per fixed distance. Utilizing common driving scenarios, we show that participants who received pace data made more accurate estimations of journey duration at various speeds, time-savings at various speed increases and the required speed to complete a journey.

  7. Protein-Pacing from Food or Supplementation Improves Physical Performance in Overweight Men and Women: The PRISE 2 Study.

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    Arciero, Paul J; Edmonds, Rohan C; Bunsawat, Kanokwan; Gentile, Christopher L; Ketcham, Caitlin; Darin, Christopher; Renna, Mariale; Zheng, Qian; Zhang, Jun Zhu; Ormsbee, Michael J

    2016-01-01

    We recently reported that protein-pacing (P; six meals/day @ 1.4 g/kg body weight (BW), three of which included whey protein (WP) supplementation) combined with a multi-mode fitness program consisting of resistance, interval sprint, stretching, and endurance exercise training (RISE) improves body composition in overweight individuals. The purpose of this study was to extend these findings and determine whether protein-pacing with only food protein (FP) is comparable to WP supplementation during RISE training on physical performance outcomes in overweight/obese individuals. Thirty weight-matched volunteers were prescribed RISE training and a P diet derived from either whey protein supplementation (WP, n = 15) or food protein sources (FP, n = 15) for 16 weeks. Twenty-one participants completed the intervention (WP, n = 9; FP, n = 12). Measures of body composition and physical performance were significantly improved in both groups (p protein source. Likewise, markers of cardiometabolic disease risk (e.g., LDL (low-density lipoprotein) cholesterol, glucose, insulin, adiponectin, systolic blood pressure) were significantly improved (p whey protein and food protein sources combined with multimodal RISE training are equally effective at improving physical performance and cardiometabolic health in obese individuals. PMID:27187451

  8. Protein-Pacing from Food or Supplementation Improves Physical Performance in Overweight Men and Women: The PRISE 2 Study

    Science.gov (United States)

    Arciero, Paul J.; Edmonds, Rohan C.; Bunsawat, Kanokwan; Gentile, Christopher L.; Ketcham, Caitlin; Darin, Christopher; Renna, Mariale; Zheng, Qian; Zhang, Jun Zhu; Ormsbee, Michael J.

    2016-01-01

    We recently reported that protein-pacing (P; six meals/day @ 1.4 g/kg body weight (BW), three of which included whey protein (WP) supplementation) combined with a multi-mode fitness program consisting of resistance, interval sprint, stretching, and endurance exercise training (RISE) improves body composition in overweight individuals. The purpose of this study was to extend these findings and determine whether protein-pacing with only food protein (FP) is comparable to WP supplementation during RISE training on physical performance outcomes in overweight/obese individuals. Thirty weight-matched volunteers were prescribed RISE training and a P diet derived from either whey protein supplementation (WP, n = 15) or food protein sources (FP, n = 15) for 16 weeks. Twenty-one participants completed the intervention (WP, n = 9; FP, n = 12). Measures of body composition and physical performance were significantly improved in both groups (p < 0.05), with no effect of protein source. Likewise, markers of cardiometabolic disease risk (e.g., LDL (low-density lipoprotein) cholesterol, glucose, insulin, adiponectin, systolic blood pressure) were significantly improved (p < 0.05) to a similar extent in both groups. These results demonstrate that both whey protein and food protein sources combined with multimodal RISE training are equally effective at improving physical performance and cardiometabolic health in obese individuals. PMID:27187451

  9. Anastomose cavo-pulmonar associada ao suporte circulatório esquerdo comparada à assistência biventricular na falência cardíaca aguda Cavo-pulmonary anastomosis associated with left ventricular in comparison with biventricular circulatory support in acute heart failure

    Directory of Open Access Journals (Sweden)

    Luis Alberto Saraiva Santos

    2012-12-01

    biventricular circulatory support or to control group. They were maintained under circulatory support and hemodynamic monitoring for 3h. Venous lactate and cytokines serum levels were also obtained. Endocardium samples were analyzed by electronic microscopy. RESULTS: FV maintenance was responsible for acute LVAD impairment after 180 min in the control group. cavo-pulmonary anastomosis resulted in non-significant improvement of LVAD pump flow in relation to control group (+55±14 ml/kg/min, P=0.072, while animals under biventricular support maintained higher LVAD flow (+93±17 ml/kg/min, P=0.012. Mean arterial pressure remained constant only in biventricular group (P<0.001, which also presented decrease of right atrial and ventricular pressures. Similar increases in lactate and cytokines levels were observed in the three groups. Ultra-structural analysis documented low levels of myocardial swelling in the biventricular group (P=0.017. CONCLUSION: The concomitant use of cavo-pulmonary anastomosis during LVAD support in a pig model of severe biventricular failure resulted in non-significant improvement of hemodynamic performance and it did not effectively replace the use of biventricular support.

  10. PACE Status Update

    Energy Technology Data Exchange (ETDEWEB)

    M., Zimring,; Hoffman, I.; Fuller, M.

    2010-08-11

    The Federal Housing Finance Agency (FHFA) regulates Fannie Mae, Freddie Mac, and the 12 Federal Home Loan Banks (the government-sponsored enterprises - GSEs). On July 6, 2010, FHFA and the Office of the Comptroller of the Currency (OCC) concluded that Property Assessed Clean Energy (PACE) programs 'present significant safety and soundness concerns' to the housing finance industry. This statement came after a year of discussions with state and federal agencies in which PACE, a novel mechanism for financing energy efficiency and renewable energy improvements, has gone from receiving support from the White House, canonization as one of Scientific American's 'World Changing Ideas' and legislative adoption in 24 states to questionable relevance, at least in the residential sector. Whether PACE resumes its expansion as an innovative tool for financing energy efficiency and clean generation depends on outcomes in each of the three branches of government - discussions on a PACE pilot phase among federal agencies, litigation in federal court, and legislation in Congress - all highly uncertain. This policy brief addresses the practical impacts of these possible outcomes on existing and emerging PACE programs across the United States and potential paths forward.

  11. Using Degraded Music Quality to Encourage a Health Improving Walking Pace: BeatClearWalker

    OpenAIRE

    Andreas Komninos; Mark Dunlop; David Rowe; Allan Hewitt; Steven Coull

    2015-01-01

    Meeting the target of 8000 steps/day, as recommended by many national governments and health authorities, can provide considerable physical and mental health benefits and is seen as a key target for reducing obesity levels and improving public health. However, to optimize the health benefits, walking should be performed at a “moderate” intensity. While there are numerous mobile fitness applications that monitor distance walked, none directly support walking at this cadence nor has there been ...

  12. Using Degraded Music Quality to Encourage a Health Improving Walking Pace: BeatClearWalker

    Directory of Open Access Journals (Sweden)

    Andreas Komninos

    2015-08-01

    Full Text Available Meeting the target of 8000 steps/day, as recommended by many national governments and health authorities, can provide considerable physical and mental health benefits and is seen as a key target for reducing obesity levels and improving public health. However, to optimize the health benefits, walking should be performed at a “moderate” intensity. While there are numerous mobile fitness applications that monitor distance walked, none directly support walking at this cadence nor has there been any research into live feedback for walking cadence. We present a smartphone fitness application to help users learn how to walk at a moderate cadence and maintain that cadence. We apply real-time audio effects that diminish the audio quality of music when the target walking cadence is not being reached. This provides an immersive and intuitive application that can easily be integrated into everyday life as allows users to walk while listening to their own music and encourages eyes-free interaction. In this paper, we introduce our approach, design, initial lab evaluation and a controlled outdoor study. Results show that using music degradation decreases the number of below-cadence steps, that users felt they worked harder with our player and would use it while exercise walking.

  13. Analysis of cardiac ventricular wall motion based on a three-dimensional electromechanical biventricular model

    International Nuclear Information System (INIS)

    This paper describes a biventricular model, which couples the electrical and mechanical properties of the heart, and computer simulations of ventricular wall motion and deformation by means of a biventricular model. In the constructed electromechanical model, the mechanical analysis was based on composite material theory and the finite-element method; the propagation of electrical excitation was simulated using an electrical heart model, and the resulting active forces were used to calculate ventricular wall motion. Regional deformation and Lagrangian strain tensors were calculated during the systole phase. Displacements, minimum principal strains and torsion angle were used to describe the motion of the two ventricles. The simulations showed that during the period of systole (1) the right ventricular free wall moves towards the septum, and at the same time, the base and middle of the free wall move towards the apex, which reduces the volume of the right ventricle; the minimum principle strain (E3) is largest at the apex, then at the middle of the free wall and its direction is in the approximate direction of the epicardial muscle fibres; (2) the base and middle of the left ventricular free wall move towards the apex and the apex remains almost static; the torsion angle is largest at the apex; the minimum principle strain E3 is largest at the apex and its direction on the surface of the middle wall of the left ventricle is roughly in the fibre orientation. These results are in good accordance with results obtained from MR tagging images reported in the literature. This study suggests that such an electromechanical biventricular model has the potential to be used to assess the mechanical function of the two ventricles, and also could improve the accuracy of ECG simulation when it is used in heart-torso model-based body surface potential simulation studies

  14. Echocardiographic estimation of acute haemodynamic response during optimization of multisite pace-maker using different pacing modalities and atrioventricular delays

    Directory of Open Access Journals (Sweden)

    Šalinger-Martinović Sonja

    2009-01-01

    Full Text Available Background/Aim. Cardiac resynchronization therapy (CRT improves ventricular dyssynchrony and is associated with an improvement in symptoms, quality of life and prognosis in patients with severe heart failure and intraventricular conduction delay. Different pacing modalities produce variable activation patterns and may be a cause of different haemodynamic changes. The aim of our study was to investigate acute haemodynamic changes with different CRT configurations during optimization procedure. Methods. This study included 30 patients with severe left ventricular systolic dysfunction and left bundle branch block with wide QRS (EF 24.33 ± 3.7%, QRS 159 ± 17.3 ms, New York Heart Association III/IV 25/5 with implanted CRT device. The whole group of patients had severe mitral regurgitation in order to measure dP/dt. After implantation and before discharge all the patients underwent optimization procedure guided by Doppler echocardiography. Left and right ventricular pre-ejection intervals (LVPEI and RVPEI, interventricular mechanical delay (IVD and the maximal rate of ventricular pressure rise during early systole (max dP/dt were measured during left and biventricular pacing with three different atrioventricular (AV delays. Results. After CRT device optimization, optimal AV delay and CRT mode were defined. Left ventricular pre-ejection intervals changed from 170.5 ± 24.6 to 145.9 ± 9.5 (p < 0.001, RVPEI from 102.4 ± 15.9 to 119.8 ± 10.9 (p < 0.001, IVD from 68.1 ± 18.3 to 26.5 ± 8.2 (p < 0.001 and dP/dt from 524.2 ± 67 to 678.2 ± 88.5 (p < 0.01. Conclusion. In patients receiving CRT echocardiographic assessment of the acute haemodynamic response to CRT is a useful tool in optimization procedure. The variability of Doppler parameters with different CRT modalities emphasizes the necessity of individualized approach in optimization procedure.

  15. Benefit of warm water immersion on biventricular function in patients with chronic heart failure

    Directory of Open Access Journals (Sweden)

    Kardassis Dimitris

    2009-07-01

    Full Text Available Abstract Background Regular physical activity and exercise are well-known cardiovascular protective factors. Many elderly patients with heart failure find it difficult to exercise on land, and hydrotherapy (training in warm water could be a more appropriate form of exercise for such patients. However, concerns have been raised about its safety. The aim of this study was to investigate, with echocardiography and Doppler, the acute effect of warm water immersion (WWI and effect of 8 weeks of hydrotherapy on biventricular function, volumes and systemic vascular resistance. A secondary aim was to observe the effect of hydrotherapy on brain natriuretic peptide (BNP. Methods Eighteen patients [age 69 ± 8 years, left ventricular ejection fraction 31 ± 9%, peakVO2 14.6 ± 4.5 mL/kg/min] were examined with echocardiography on land and in warm water (34°C. Twelve of these patients completed 8 weeks of control period followed by 8 weeks of hydrotherapy twice weekly. Results During acute WWI, cardiac output increased from 3.1 ± 0.8 to 4.2 ± 0.9 L/min, LV tissue velocity time integral from 1.2 ± 0.4 to 1.7 ± 0.5 cm and right ventricular tissue velocity time integral from 1.6 ± 0.6 to 2.5 ± 0.8 cm (land vs WWI, p There was no change in the cardiovascular response or BNP after 8 weeks of hydrotherapy. Conclusion Hydrotherapy was well tolerated by all patients. The main observed cardiac effect during acute WWI was a reduction in heart rate, which, together with a decrease in afterload, resulted in increases in systolic and diastolic biventricular function. Although 8 weeks of hydrotherapy did not improve cardiac function, our data support the concept that exercise in warm water is an acceptable regime for patients with heart failure.

  16. Cardiac Failure after Liver Transplantation Requiring a Biventricular Assist Device

    Directory of Open Access Journals (Sweden)

    Rita Jermyn

    2014-01-01

    Full Text Available Increased hepatic iron load in extrahepatic organs of cirrhotic patients with and without hereditary hemochromatosis portends a poorer long term prognosis after liver transplant. Hepatic as well as nonhepatic iron overload is associated with increased infectious and postoperative complications, including cardiac dysfunction. In this case report, we describe a cirrhotic patient with alpha 1 antitrypsin deficiency and nonhereditary hemochromatosis (non-HFE that developed cardiogenic shock requiring mechanical circulatory support for twenty days after liver transplant. Upon further investigation, she was found to have significant iron deposition in both the liver and heart biopsies. Her heart regained complete and sustained recovery following ten days of mechanical biventricular support. This case highlights the importance of preoperatively recognizing extrahepatic iron deposition in patients referred for liver transplantation irrespective of etiology of liver disease as this may prevent postoperative complications.

  17. A case of biventricular endomyocardial fibrosis complicated by right ventricular outflow tract aneurysms.

    Science.gov (United States)

    Gonçalves, Ricardo; Meel, Ruchika

    2016-01-01

    Endomyocardial fibrosis remains a major public health problem worldwide. It is a restrictive cardiomyopathy, of uncertain aetiology, which may lead to right, left or biventricular heart failure. Progress continues to be made in understanding the prevalence and natural history of this disease. Specific treatment, apart from surgery, remains suboptimal. We report a case of advanced, biventricular EMF complicated by right ventricular outflow tract aneurysms. PMID:27245722

  18. Self-Paced Fortran.

    Science.gov (United States)

    Burnett, James

    1979-01-01

    This paper describes the instructional format of the lecture and the self-paced methods of teaching FORTRAN at Michigan State University and compares end-of-term grades of students taking a second computer science course based on whether they took the first course in the self-paced or the traditional lecture format. (Author/BB)

  19. Pre-ejection period by radial artery tonometry supplements echo doppler findings during biventricular pacemaker optimization

    Directory of Open Access Journals (Sweden)

    Qamruddin Salima

    2011-07-01

    Full Text Available Abstract Background Biventricular (Biv pacemaker echo optimization has been shown to improve cardiac output however is not routinely used due to its complexity. We investigated the role of a simple method involving computerized pre-ejection time (PEP assessment by radial artery tonometry in guiding Biv pacemaker optimization. Methods Blinded echo and radial artery tonometry were performed simultaneously in 37 patients, age 69.1 ± 12.8 years, left ventricular (LV ejection fraction (EF 33 ± 10%, during Biv pacemaker optimization. Effect of optimization on echo derived velocity time integral (VTI, ejection time (ET, myocardial performance index (MPI, radial artery tonometry derived PEP and echo-radial artery tonometry derived PEP/VTI and PEP/ET indices was evaluated. Results Significant improvement post optimization was achieved in LV ET (286.9 ± 37.3 to 299 ± 34.6 ms, p Conclusion An acute shortening of PEP by radial artery tonometry occurs post Biv pacemaker optimization and correlates with improvement in hemodynamics by echo Doppler and may provide a cost-efficient approach to assist with Biv pacemaker echo optimization.

  20. Pacing stress echocardiography

    OpenAIRE

    Agrusta Marco; Gligorova Suzana

    2005-01-01

    Abstract Background High-rate pacing is a valid stress test to be used in conjunction with echocardiography; it is independent of physical exercise and does not require drug administration. There are two main applications of pacing stress in the echo lab: the noninvasive detection of coronary artery disease through induction of a regional transient dysfunction; and the assessment of contractile reserve through peak systolic pressure/ end-systolic volume relationship at increasing heart rates ...

  1. Pacing stress echocardiography

    Directory of Open Access Journals (Sweden)

    Agrusta Marco

    2005-12-01

    Full Text Available Abstract Background High-rate pacing is a valid stress test to be used in conjunction with echocardiography; it is independent of physical exercise and does not require drug administration. There are two main applications of pacing stress in the echo lab: the noninvasive detection of coronary artery disease through induction of a regional transient dysfunction; and the assessment of contractile reserve through peak systolic pressure/ end-systolic volume relationship at increasing heart rates to assess global left ventricular contractility. Methods The pathophysiologic rationale of pacing stress for noninvasive detection of coronary artery disease is obvious, with the stress determined by a controlled increase in heart rate, which is a major determinant of myocardial oxygen demand, and thereby tachycardia may exceed a fixed coronary flow reserve in the presence of hemodynamically significant coronary artery disease. The use of pacing stress echo to assess left ventricular contractile reserve is less established, but promising. Positive inotropic interventions are mirrored by smaller end-systolic volumes and higher end-systolic pressures. An increased heart rate progressively increases the force of ventricular contraction (Bowditch treppe or staircase phenomenon. To build the force-frequency relationship, the force is determined at different heart rate steps as the ratio of the systolic pressure (cuff sphygmomanometer/end-systolic volume index (biplane Simpson rule. The heart rate is determined from ECG. Conclusion Two-dimensional echocardiography during pacing is a useful tool in the detection of coronary artery disease. Because of its safety and ease of repeatability noninvasive pacing stress echo can be the first-line stress test in patients with permanent pacemaker. The force-frequency can be defined as up- sloping (normal when the peak stress pacing systolic pressure/end-systolic volume index is higher than baseline and intermediate stress

  2. Use of a Three Dimensional Printed Cardiac Model to Assess Suitability for Biventricular Repair.

    Science.gov (United States)

    Farooqi, Kanwal M; Gonzalez-Lengua, Carlos; Shenoy, Rajesh; Sanz, Javier; Nguyen, Khanh

    2016-05-01

    Three dimensional (3D) printing is rapidly gaining interest in the medical field for use in presurgical planning. We present the case of a seven-year-old boy with double outlet right ventricle who underwent a bidirectional Glenn anastomosis. We used a 3D cardiac model to assess his suitability for a biventricular repair. He underwent a left ventricle-to-aorta baffle with a right ventricle-to-pulmonary artery conduit placement. He did well postoperatively and was discharged home with no evidence of baffle obstruction and good biventricular function. A 3D printed model can provide invaluable intracardiac spatial information in these complex patients. PMID:27009890

  3. Promoting continence in nursing homes in four European countries: the use of PACES as a mechanism for improving the uptake of evidence-based recommendations

    Science.gov (United States)

    Harvey, Gill; Kitson, Alison; Munn, Zachary

    2012-01-01

    Background Multi-faceted approaches are generally recognised as the most effective way to support the implementation of evidence into practice. Audit and feedback often constitute one element of a multi-faceted implementation package, alongside other strategies, such as interactive education and facilitated support mechanisms. This paper describes a multi-faceted implementation strategy that used the Joanna Briggs Institute Practical Application of Clinical Evidence System (PACES) as an online audit tool to support facilitators working to introduce evidence-based continence recommendations in nursing homes in four different European countries. Aims/objectives The paper describes the experience of using PACES with an international group of nursing home facilitators. In particular, the objectives of the paper are: to describe the process of introducing PACES to internal facilitators in eight nursing homes; to discuss the progress made during a 12-month period of collecting and analysing audit data using PACES; to summarise the collective experience of using PACES, including reflections on its strengths and limitations. Methods Descriptive data were collected during the 12-month period of working with PACES in the eight nursing home sites. These data included digital and written notes taken at an initial 3-day introductory programme, at monthly teleconferences held between the external and internal facilitators and at a final 2-day meeting. Qualitative analysis of the data was undertaken on an ongoing basis throughout the implementation period, which enabled formative evaluation of PACES. A final summative evaluation of the experience of using PACES was undertaken as part of the closing project meeting in June 2011. Results The nursing home facilitators took longer than anticipated to introduce PACES and it was only after 9–10 months that they became confident and comfortable using the system. This was due to a combination of factors, including a lack of audit

  4. Transferring PACE Assessments Upon Home Sale

    Energy Technology Data Exchange (ETDEWEB)

    National Renewable Energy Laboratory (NREL); Coughlin, Jason; Fuller, Merrian; Zimring, Mark

    2010-04-12

    A significant barrier to investing in renewable energy and comprehensive energy efficiency improvements to homes across the country is the initial capital cost. Property Assessed Clean Energy (PACE) financing is one of several new financial models broadening access to clean energy by addressing this upfront cost issue. Recently, the White House cited PACE programs as an important element of its 'Recovery through Retrofit' plan. The residential PACE model involves the creation of a special clean energy financing district that homeowners elect to opt into. Once opted in, the local government (usually at the city or county level) finances the upfront investment of the renewable energy installation and/or energy efficiency improvements. A special lien is attached to the property and the assessment is paid back as a line item on the property tax bill. As of April 2010, 17 states have passed legislation to allow their local governments to create PACE programs, two already have the authority to set up PACE programs, and over 10 additional states are actively developing enabling legislation. This policy brief analyzes one of the advantages of PACE, which is the transferability of the special assessment from one homeowner to the next when the home is sold. This analysis focuses on the potential for the outstanding lien to impact the sales negotiation process, rather than the legal nature of the lien transfer itself. The goal of this paper is to consider what implications a PACE lien may have on the home sales negotiation process so that it can be addressed upfront rather than risk a future backlash to PACE programs. If PACE programs do expand at a rapid rate, the chances are high that there will be other cases where prospective buyers uses PACE liens to negotiate lower home prices or require repayment of the lien as a condition of sale. As a result, PACE programs should highlight this issue as a potential risk factor for the sake of full disclosure. A good example

  5. Optimized multisite ventricular pacing in postoperative single-ventricle patients.

    Science.gov (United States)

    Havalad, Vinod; Cabreriza, Santos E; Cheung, Eva W; Aponte-Patel, Linda; Wang, Alice; Cheng, Bin; Wang, Daniel Y; Silver, Eric; Bacha, Emile A; Spotnitz, Henry M

    2014-10-01

    Ventricular dyssynchrony is associated with morbidity and mortality after palliation of a single ventricle. The authors hypothesized that resynchronization with optimized temporary multisite pacing postoperatively would be safe, feasible, and effective. Pacing was assessed in the intensive care unit within the first 24 h after surgery. Two unipolar atrial pacing leads and four bipolar ventricular pacing leads were placed at standardized sites intraoperatively. Pacing was optimized to maximize mean arterial pressure. The protocol tested 11 combinations of the 4 different ventricular lead sites, 6 atrioventricular delays (50-150 ms), and 14 intraventricular delays. Optimal pacing settings were thus determined and ultimately compared in four configurations: bipolar, unipolar, single-site atrioventricular pacing, and intrinsic rhythm. Each patient was his or her own control, and all pacing comparisons were implemented in random sequence. Single-ventricle palliation was performed for 17 children ages 0-21 years. Pacing increased mean arterial pressure (MAP) versus intrinsic rhythm, with the following configurations: bipolar multisite pacing increased MAP by 2.2 % (67.7 ± 2.4 to 69.2 ± 2.4 mmHg; p = 0.013) and unipolar multisite pacing increased MAP by 2.8 % (67.7 ± 2.4 to 69.6 ± 2.7 mmHg; p = 0.002). Atrioventricular single-site pacing increased MAP by 2.1 % (67.7 ± 2.4 to 69.1 ± 2.5 mmHg: p = 0.02, insignificant difference under Bonferroni correction). The echocardiographic fractional area change in nine patients increased significantly only with unipolar pacing (32 ± 3.1 to 36 ± 4.2 %; p = 0.02). No study-related adverse events occurred. Multisite pacing optimization is safe and feasible in the early postoperative period after single-ventricle palliation, with improvements in mean arterial pressure and fractional area shortening. Further study to evaluate clinical benefits is required. PMID:24827078

  6. Promoting continence in nursing homes in four European countries: the use of PACES as a mechanism for improving the uptake of evidence-based recommendations

    OpenAIRE

    Harvey, Gill; Kitson, Alison; Munn, Zachary

    2012-01-01

    Background Multi-faceted approaches are generally recognised as the most effective way to support the implementation of evidence into practice. Audit and feedback often constitute one element of a multi-faceted implementation package, alongside other strategies, such as interactive education and facilitated support mechanisms. This paper describes a multi-faceted implementation strategy that used the Joanna Briggs Institute Practical Application of Clinical Evidence System (PACES) as an onlin...

  7. Application of programmable, autonomously controlled electrode (PACE) technology to the development of an improved pulsed field gel electrophoresis assay for DNA double-strand breaks in mammalian cells

    International Nuclear Information System (INIS)

    PACE (programmable, autonomously controlled electrodes) pulsed field gel electrophoresis technology was used to develop a DNA double-strand break assay that simultaneously combined (1) resolution across a broad range of DNA sizes, (2) high sensitivity (in terms of detecting dsb at low doses) and (3) speed. A 48h PACE/dsb assay resolves DNA fragments ranging in size from 0.2 to 6 Mb, and detects damage induced by as little as 2 Gy of γ-radiation. A different set of electrophoretic conditions resolves DNA between 1.5 and 6 megabases in 23 h, with a detection limit of about 5 Gy. A third electrophoretic protocol, while not resolving DNA fragments greater than 50 kb in length, detects DNA dsb in CHO cells induced by 15 Gy or more of γ-rays after only a 1h run. In particular, the 48h PACE/dsb assay should prove useful in studies aimed at understanding the mechanisms whereby a variety of biological, chemical and physical agents induce DNA dsb in eukaryotes. (author)

  8. Controlled transient respiratory arrest along with rapid right ventricular pacing for improving balloon stability during balloon valvuloplasty in pediatric patients with congenital aortic stenosis - A retrospective case series analysis

    Directory of Open Access Journals (Sweden)

    Gupta Sampa

    2010-01-01

    Full Text Available Rapid right ventricular pacing is safe, effective, and established method to provide balloon stability during balloon aortic valvuloplasty (BAV. Controlled transient respiratory arrest at this point of time may further reduce left ventricular stroke volume, providing an additional benefit to maintain balloon stability. Two groups were studied. Among the 10 patients, five had rapid pacing alone (Group A, while the other five were provided with cessation of positive pressure breathing as well (Group B. The outcomes of BAV in the two groups of patients were studied. One patient in Group A had failed balloon dilatation even after the fourth attempt, while in Group B there were no failures. The peak systolic gradient reduction was higher in Group B (70.05% in comparison to 52.16% of group A. In Group A, five subjects developed aortic regurgitation (grade 2 in four and grade 3 in one, while no grade 3 aortic regurgitation developed in any patient in Group B. Controlled transient respiratory arrest along with rapid ventricular pacing may be effective in maintaining balloon stability and improve the outcome of BAV.

  9. Controlled transient respiratory arrest along with rapid right ventricular pacing for improving balloon stability during balloon valvuloplasty in pediatric patients with congenital aortic stenosis--a retrospective case series analysis.

    Science.gov (United States)

    Gupta, Sampa Dutta; Das, Soumi; Ghose, Tapas; Sarkar, Achyut; Goswami, Anupam; Kundu, Sudeshna

    2010-01-01

    Rapid right ventricular pacing is safe, effective, and established method to provide balloon stability during balloon aortic valvuloplasty (BAV). Controlled transient respiratory arrest at this point of time may further reduce left ventricular stroke volume, providing an additional benefit to maintain balloon stability. Two groups were studied. Among the 10 patients, five had rapid pacing alone (Group A), while the other five were provided with cessation of positive pressure breathing as well (Group B). The outcomes of BAV in the two groups of patients were studied. One patient in Group A had failed balloon dilatation even after the fourth attempt, while in Group B there were no failures. The peak systolic gradient reduction was higher in Group B (70.05% in comparison to 52.16% of group A). In Group A, five subjects developed aortic regurgitation (grade 2 in four and grade 3 in one, while no grade 3 aortic regurgitation developed in any patient in Group B). Controlled transient respiratory arrest along with rapid ventricular pacing may be effective in maintaining balloon stability and improve the outcome of BAV. PMID:20826965

  10. Enact legislation supporting residential property assessed clean energy financing (PACE)

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Devashree

    2012-11-15

    Congress should enact legislation that supports residential property assessed clean energy (PACE) programs in the nation’s states and metropolitan areas. Such legislation should require the Federal Housing Finance Agency (FHFA) to allow Fannie Mae and Freddie Mac to purchase residential mortgages with PACE assessments while at the same time providing responsible underwriting standards and a set of benchmarks for residential PACE assessments in order to minimize financial risks to mortgage holders. Congressional support of residential PACE financing will improve energy efficiency, encourage job creation, and foster economic growth in the nation’s state and metropolitan areas.

  11. Effects of milrinone and epinephrine or dopamine on biventricular function and hemodynamics in an animal model with right ventricular failure after pulmonary artery banding.

    Science.gov (United States)

    Hyldebrandt, Janus Adler; Sivén, Eleonora; Agger, Peter; Frederiksen, Christian Alcaraz; Heiberg, Johan; Wemmelund, Kristian Borup; Ravn, Hanne Berg

    2015-07-01

    Right ventricular (RV) failure due to chronic pressure overload is a main determinant of outcome in congenital heart disease. Medical management is challenging because not only contractility but also the interventricular relationship is important for increasing cardiac output. This study evaluated the effect of milrinone alone and in combination with epinephrine or dopamine on hemodynamics, ventricular performance, and the interventricular relationship. RV failure was induced in 21 Danish landrace pigs by pulmonary artery banding. After 10 wk, animals were reexamined using biventricular pressure-volume conductance catheters. The maximum pressure in the RV increased by 113% (P HR; 21%, P HR in a dose-dependent manner but without any significant differences between the two interventions. A more pronounced increase in biventricular contractility was observed in the dopamine-treated animals. LV volume was reduced in both the dopamine and epinephrine groups with increasing doses In the failing pressure overloaded RV, milrinone improved CI and increased contractility. Albeit additional dose-dependent effects of both epinephrine and dopamine on CI and contractility, neither of the interventions improved SVI due to reduced filling of the LV. PMID:25957222

  12. Self-Paced Instruction: Hello, Education

    Science.gov (United States)

    Leuba, Richard J.; Flammer, Gordon H.

    1975-01-01

    Answers criticisms of self-paced instruction (SPI) by citing advantages of SPI over lecture methods. Concludes that criticisms of SPI are useful since they indicate in which areas further research should be conducted to improve this method of instruction. (MLH)

  13. Outcome of biventricular repair in infants with multiple left heart obstructive lesions.

    Science.gov (United States)

    Cavigelli-Brunner, Anna; Bauersfeld, Urs; Prêtre, René; Kretschmar, Oliver; Oxenius, Angela; Valsangiacomo Buechel, Emanuela R

    2012-04-01

    The decision to perform biventricular repair for infants with multiple obstructive or hypoplastic left heart lesions (LHL) and borderline left ventricle (LV) may be controversial. This study sought to assess the mortality and morbidity of patients with LHL after biventricular repair and to determine the growth of the left-sided cardiac structures. Retrospective analysis of 39 consecutive infants with LHL who underwent biventricular repair was performed. The median age at surgery was 7 days (range 1-225 days), and the median follow-up period was 34 months (range 1-177 months). Between diagnosis and the end of the follow-up period, the size of the aortic annulus (z-score -4.1 ± 2.8 vs. -0.1 ± 2.7) and the LV (LV end-diastolic diameter z-score -1.7 ± 2.8 vs. 0.21 ± 1.7) normalized. During the follow-up period, 23 patients required 39 reinterventions (62%) consisting of redo surgery for 21 patients (57%) and catheter-guided reinterventions for 8 patients (22%). At the end of the follow-up period, 25 of 34 patients were doing subjectively well; 10 children (29%) received cardiac medication; 12 (35%) presented with failure to thrive (weight ≤ P3) and 5 (15%) with pulmonary hypertension. The overall mortality rate was 13%. Biventricular repair for patients with multiple LHL results in sufficient growth of the left-sided cardiac structures. Nevertheless, residual or newly developing obstructive lesions and pulmonary hypertension are frequent, causing significant morbidity that requires reintervention. PMID:22159427

  14. Is hydrotherapy an appropriate form of exercise for elderly patients with biventricular systolic heart failure?

    OpenAIRE

    Bente Grüner Sveälv; Margareta Scharin Täng; Åsa Cider

    2012-01-01

    Hydrotherapy (exercise in warm water) is considered to be a safe and beneficial method to use in the rehabilitation of stable heart failure patients, but there is little information on the effect of the increased venous return and enhanced preload in elderly patients with biventricular heart failure. We present a case of an elderly man who was recruited to participate in a hydrotherapy study. We compared echocardiographic data during warm water immersion with land measurements, and observed i...

  15. A Coupled Biventricular Finite Element and Lumped Parameter Circulatory System Model of Heart Failure

    OpenAIRE

    Wenk, Jonathan F.; Ge, Liang; Zhang, Zhihong; Soleimani, Mehrdad; Potter, D Dean; Wallace, Arthur W.; Ratcliffe, Mark B.; Guccione, Julius M.

    2012-01-01

    Numerical modeling of the cardiovascular system is becoming an important tool for assessing the influence of heart disease and treatment therapies. In the current study we present an approach for modeling the interaction between the heart and circulatory system. This was accomplished by creating animal specific biventricular finite element models, which characterize the mechanical response of the heart, and coupling them to a lumped parameter model that represents the systemic and pulmonic ci...

  16. A coupled biventricular finite element and lumped-parameter circulatory system model of heart failure

    OpenAIRE

    Wenk, JF; Ge, L.; Zhang, Z.; Soleimani, M.; Potter, DD; Wallace, AW; Tseng, E; Ratcliffe, MB; Guccione, JM

    2012-01-01

    Numerical modelling of the cardiovascular system is becoming an important tool for assessing the influence of heart disease and treatment therapies. In the current study, we present an approach for modelling the interaction between the heart and the circulatory system. This was accomplished by creating animal-specific biventricular finite element (FE) models, which characterise the mechanical response of the heart, and by coupling them to a lumped-parameter model that represents the systemic ...

  17. Atrial Fibrillation and Pacing Algorithms

    OpenAIRE

    Terranova, Paolo; Severgnini, Barbara; Valli, Paolo; Dell'Orto, Simonetta; Greco, Enrico Maria

    2006-01-01

    Pacing prevention algorithms have been introduced in order to maximize the benefits of atrial pacing in atrial fibrillation prevention. It has been demonstrated that algorithms actually keep overdrive atrial pacing, reduce atrial premature contractions, and prevent short-long atrial cycle phenomenon, with good patient tolerance. However, clinical studies showed inconsistent benefits on clinical endpoints such as atrial fibrillation burden. Factors which may be responsible for neutral results ...

  18. Multi-scale deep networks and regression forests for direct bi-ventricular volume estimation.

    Science.gov (United States)

    Zhen, Xiantong; Wang, Zhijie; Islam, Ali; Bhaduri, Mousumi; Chan, Ian; Li, Shuo

    2016-05-01

    Direct estimation of cardiac ventricular volumes has become increasingly popular and important in cardiac function analysis due to its effectiveness and efficiency by avoiding an intermediate segmentation step. However, existing methods rely on either intensive user inputs or problematic assumptions. To realize the full capacities of direct estimation, this paper presents a general, fully learning-based framework for direct bi-ventricular volume estimation, which removes user inputs and unreliable assumptions. We formulate bi-ventricular volume estimation as a general regression framework which consists of two main full learning stages: unsupervised cardiac image representation learning by multi-scale deep networks and direct bi-ventricular volume estimation by random forests. By leveraging strengths of generative and discriminant learning, the proposed method produces high correlations of around 0.92 with ground truth by human experts for both the left and right ventricles using a leave-one-subject-out cross validation, and largely outperforms existing direct methods on a larger dataset of 100 subjects including both healthy and diseased cases with twice the number of subjects used in previous methods. More importantly, the proposed method can not only be practically used in clinical cardiac function analysis but also be easily extended to other organ volume estimation tasks. PMID:26919699

  19. Novel insights on effect of atrioventricular programming of biventricular pacemaker in heart failure – a case series

    Directory of Open Access Journals (Sweden)

    Rafique Asim M

    2006-10-01

    Full Text Available Abstract Background Echocardiography plays an integral role in the diagnosis of congestive heart failure including measurement of left heart pressure as well as mechanical dyssynchrony. Methods In this report we describe novel therapeutic uses of echo pulsed wave Doppler in atrioventricular pacemaker optimization in patients who had either not derived significant symptomatic benefit post biventricular pacemaker implantation or deteriorated after deriving initial benefit. In these patients atrioventricular optimization showed novel findings and improved cardiac output and symptoms. Results In 3 patients with Cheyne Stokes pattern of respiration echo Doppler showed worsening of mitral regurgitation during hyperpneac phase in one patient, marked E and A fusion in another patient and exaggerated ventricular interdependence in a third patient thus highlighting mechanisms of adverse effects of Cheyne Stokes respiration in patients with heart failure. All 3 patients required a very short atrioventricular delay programming for best cardiac output. In one patient with recurrent congestive heart failure post cardiac resynchronization, mitral inflow pulse wave Doppler showed no A wave until a sensed atrioventricular delay of 190 ms was reached and showed progressive improvement in mitral inflow pattern until an atrioventricular delay of 290 ms. In 2 patients atrioventricular delay as short as 50 ms was required to allow E and A separation and prevent diastolic mitral regurgitation. All patients developed marked improvement in congestive heart failure symptoms post echo-guided biv pacemaker optimization. Conclusion These findings highlight the value of echo-guided pacemaker optimization in symptomatic patients post cardiac resynchronization treatment.

  20. Protein-Pacing and Multi-Component Exercise Training Improves Physical Performance Outcomes in Exercise-Trained Women: The PRISE 3 Study.

    Science.gov (United States)

    Arciero, Paul J; Ives, Stephen J; Norton, Chelsea; Escudero, Daniela; Minicucci, Olivia; O'Brien, Gabe; Paul, Maia; Ormsbee, Michael J; Miller, Vincent; Sheridan, Caitlin; He, Feng

    2016-01-01

    The beneficial cardiometabolic and body composition effects of combined protein-pacing (P; 5-6 meals/day at 2.0 g/kg BW/day) and multi-mode exercise (resistance, interval, stretching, endurance; RISE) training (PRISE) in obese adults has previously been established. The current study examines PRISE on physical performance (endurance, strength and power) outcomes in healthy, physically active women. Thirty exercise-trained women (>4 days exercise/week) were randomized to either PRISE (n = 15) or a control (CON, 5-6 meals/day at 1.0 g/kg BW/day; n = 15) for 12 weeks. Muscular strength (1-RM bench press, 1-RM BP) endurance (sit-ups, SUs; push-ups, PUs), power (bench throws, BTs), blood pressure (BP), augmentation index, (AIx), and abdominal fat mass were assessed at Weeks 0 (pre) and 13 (post). At baseline, no differences existed between groups. Following the 12-week intervention, PRISE had greater gains (p < 0.05) in SUs, PUs (6 ± 7 vs. 10 ± 7, 40%; 8 ± 13 vs. 14 ± 12, 43% ∆reps, respectively), BTs (11 ± 35 vs. 44 ± 34, 75% ∆watts), AIx (1 ± 9 vs. -5 ± 11, 120%), and DBP (-5 ± 9 vs. -11 ± 11, 55% ∆mmHg). These findings suggest that combined protein-pacing (P; 5-6 meals/day at 2.0 g/kg BW/day) diet and multi-component exercise (RISE) training (PRISE) enhances muscular endurance, strength, power, and cardiovascular health in exercise-trained, active women. PMID:27258301

  1. Correção biventricular em defeito do septo atrioventricular desbalanceado Corrección biventricular en defecto del septo atrioventricular desbalanceado Biventricular repair in unbalanced atrioventricular septal defect

    OpenAIRE

    Edmar Atik; Patrícia O. Marques; Rogério A. Miranda; Vitor C. Guerra; Lucília Santana Faria; Marcelo Jatene

    2009-01-01

    É apresentada a evolução favorável, após correção operatória biventricular, de criança com 2,5 anos de idade, com defeito do septo atrioventricular desbalanceado, com ventrículo esquerdo (VE) pequeno (anel mitral de 10 mm em relação de 0,4 com o anel tricúspide, DDVE de 17 mm, Vd2 VE de 15 ml/m² e relação do índice longitudinal VE/VD de 0,71). Houve desenvolvimento normal do VE, verificado três meses após a operação (anel mitral de 22 mm, em relação de 0,84 com o da valva tricúspide e DDVE de...

  2. Marathon pacing and elevation change

    CERN Document Server

    Elliott, J B

    2012-01-01

    An analysis of marathon pacing and elevation change is presented. It is based on an empirical observation of how the pace of elite and non-elite marathon runners change over the course of the marathon and a simple approximation of the energy cost of ascent and decent. It was observed that the pace of the runners slowed in a regular manner that could be broken up into four regions. That observation can be used to project target paces for a desired marathon finish time. However, that estimate fails to take in to account the energetic costs of elevation changes (hills) along the marathon course. Several approximations are made to give a coarse estimate of target paces for marathon run on courses with significant elevation changes, i.e. a hilly course. The 2012 Oakland Marathon course is used as and example of a hilly course and the times of 23 finishers are examined.

  3. Atrioventricular Junction Ablation in Atrial Fibrillation: Choosing The Right Patient and Pacing Device

    Directory of Open Access Journals (Sweden)

    Finn Akerstr�m; Mois�s Rodr�guez-Ma�ero; Marta Pach�n; Alberto Puchol; X. Alberte Fern�ndez-L�pez; Luis Mart�nez-Sande; Miguel Valderr�bano MD; Miguel A. Arias.

    2015-08-01

    Full Text Available Atrial fibrillation (AF is the most common cardiac arrhythmia and despite advancements in rhythm control through direct catheter ablation, maintaining sinus rhythm is currently not possible in a large proportion of AF patients. Furthermore, in some instances pharmacological rate control may be insufficient, resulting in a highly symptomatic patient at risk of developing tachycardia-induced cardiomyopathy and heart failure (HF. Catheter ablation of the atrioventricular junction (AVJ with subsequent permanent pacemaker implantation provides definite rate control and represents an attractive therapeutic option when pharmacological rate control is not achieved. In those with reduced ventricular function, cardiac resynchronization therapy (CRT should be considered over right ventricular apical (RVA pacing in order to avoid the deleterious effects associated with a high amount of chronic RVA pacing. Another group of patients that may also benefit from AVJ ablation are HF patients with concomitant AF receiving CRT. In this patient cohort AVJ ablation ensures near 100% biventricular pacing, thus allowing optimization of the therapeutic effects of CRT.

  4. Pneumothorax in cardiac pacing

    DEFF Research Database (Denmark)

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard;

    2012-01-01

    AIM: To identify risk factors for pneumothorax treated with a chest tube after cardiac pacing device implantation in a population-based cohort.METHODS AND RESULTS: A nationwide cohort study was performed based on data on 28 860 patients from the Danish Pacemaker Register, which included all Danish...... patients who received their first pacemaker (PM) or cardiac resynchronization device from 1997 to 2008. Multiple logistic regression was used to estimate adjusted odds ratios (aOR) with 95% confidence intervals for the association between risk factors and pneumothorax treated with a chest tube. The median...... age was 77 years (25th and 75th percentile: 69-84) and 55% were male (n = 15 785). A total of 190 patients (0.66%) were treated for pneumothorax, which was more often in women [aOR 1.9 (1.4-2.6)], and in patients with age >80 years [aOR 1.4 (1.0-1.9)], a prior history of chronic obstructive pulmonary...

  5. Historical highlights in cardiac pacing.

    Science.gov (United States)

    Geddes, L A

    1990-01-01

    The benchmarks in cardiac pacing are identified, beginning with F. Steiner (1871), who rhythmically stimulated the chloroform-arrested hearts of 3 horses, 1 donkey, 10 dogs, 14 cats, and 8 rabbits. The chloroform-arrested heart in human subjects was paced by T. Greene in the following year (1872) in the UK. In 1882, H. Ziemssen in Germany applied cardiac pacing to a 42-year old woman who had a large defect in the anterior left chest wall subsequent to resection of an enchondroma. Intentional cardiac pacing did not occur until 1932, when A.A. Hyman in the US demonstrated that cardiac pacing could be clinically practical. Hyman made a batteryless pacemaker for delivery in induction shock stimuli (60-120/min) to the atria. His pacemaker was powered by a hand-wound, spring-driven generator which provided 6 min of pacemaking without rewinding. Closed-chest ventricular pacing was introduced in the US in 1952 by P.M. Zoll et al. Zoll (1956) also introduced closed-chest ventricular defibrillation. W.L. Weirich et al. (1958) demonstrated that direct-heart stimulation in closed-chest patients could be achieved with slender wire electrodes. S. Furman and J.B. Schwedel (1959) developed a monopolar catheter electrode for ventricular pacing in man. In the same year, W. Greatbatch and W.M. Chardack developed the implantable pacemaker. PMID:18238328

  6. Estrogen-induced improvement in coronary flow responses during atrial pacing in relation to endothelin-1 levels in postmenopausal women without coronary disease

    Directory of Open Access Journals (Sweden)

    Ioannis Kallikazaros

    2008-06-01

    Full Text Available Ioannis Kallikazaros, Costas Tsioufis, Panagiotis Zambaras, Ioannis Skiadas, Marina Toutouza, Dimitrios Tousoulis, Christodoulos Stefanadis, Pavlos ToutouzasCardiology Department and University Cardiology Clinic, Hippokration Hospital of Athens, GreeceBackground: The cardioprotective role of hormonal replacement therapy remains in doubt, but interest is increasing in the vascular effects of estrogens especially in coronary circulation.Methods: Coronary blood flow (CBF was measured in 24 postmenopausal women (age 55 ± 3 years, whose coronary arteries appeared angiographically normal, during incremental atrial pacing (AP before and 20 minutes after intracoronary administration of either 75 ng/mL 17-β estradiol (treated group, n = 18 or 0.9% saline (controls, n = 6.Results: Before estrogen, no differences in the coronary vasomotor responses at AP between the two groups (p = NS could be detected. After estrogen, in the treated group, at the peak of the second AP, the coronary artery diameter decreased by 0.17 mm (p < 0.005 while the CBF increased by 61 mL/min (p < 0.05. These changes differed significantly from thoseobserved at the peak of first AP (p < 0.001 for both cases. In contrast, in the control group no such changes were observed. The endothelin-1 (ET-1 levels in the coronary sinus were significantly reduced after estrogen infusion, which was negatively correlated with the degree of coronary artery constriction (r = −0.40, p = 0.03 and positively correlated with the increase in CBF (r = 0.54, p = 0.01.Conclusions: In postmenopausal women without coronary artery disease, the intracoronary estrogen infusion mediates a greater increase in CBF and is positively correlated with the reduction of the coronary sinus ET-1 levels at the peak of AP.Keywords: estrogens, coronary blood flow, endothelin-1, coronary interventions

  7. Biventricular heart failure secondary to a pericardial cystic mass: case report

    Energy Technology Data Exchange (ETDEWEB)

    Nizzero, A. [Sudbury Regional Hospital, Dept. of Diagnostic Imaging, Sudbury, Ontario (Canada); Dobranowski, J. [St. Joseph' s Hospital, Dept. of Radiology, Hamilton, Ontario (Canada); Tanser, P. [St. Joseph' s Hospital, Dept. of Cardiology, Hamilton, Ontario (Canada)

    2000-07-01

    Cystic masses of the pericardium causing symptoms due to cardiac compression are very unusual. Such cysts may be congenital, or they may occur secondary to inflammatory processes or hemorrhage, similar to cysts seen in the pleura or peritoneum. Echocardiography, computed tomography (CT) and magnetic resonance imaging (MRI) are useful for noninvasive investigation of the pericardium, although in the remote past, definitive diagnosis was possible only with thoracotomy. We present a case of biventricular cardiac failure secondary to a calcified pericardial cystic mass in a patient with constrictive pericarditis. Because of the extensive calcification, echocardiography was not helpful. CT and MRI allowed excellent delineation of the nature and effects of this abnormality. (author)

  8. Factors influencing pacing in triathlon

    Directory of Open Access Journals (Sweden)

    Wu SSX

    2014-09-01

    Full Text Available Sam SX Wu,1 Jeremiah J Peiffer,2 Jeanick Brisswalter,3 Kazunori Nosaka,1 Chris R Abbiss1 1Centre for Exercise and Sports Science Research, School of Exercise and Health Sciences, Edith Cowan University, Perth, WA, Australia; 2School of Psychology and Exercise Science, Murdoch University, Perth, WA, Australia; 3Laboratory of Human Motricity, Education Sport and Health, University of Nice Sophia Antipolis, Nice, France Abstract: Triathlon is a multisport event consisting of sequential swim, cycle, and run disciplines performed over a variety of distances. This complex and unique sport requires athletes to appropriately distribute their speed or energy expenditure (ie, pacing within each discipline as well as over the entire event. As with most physical activity, the regulation of pacing in triathlon may be influenced by a multitude of intrinsic and extrinsic factors. The majority of current research focuses mainly on the Olympic distance, whilst much less literature is available on other triathlon distances such as the sprint, half-Ironman, and Ironman distances. Furthermore, little is understood regarding the specific physiological, environmental, and interdisciplinary effects on pacing. Therefore, this article discusses the pacing strategies observed in triathlon across different distances, and elucidates the possible factors influencing pacing within the three specific disciplines of a triathlon. Keywords: cycle, endurance, multisport, pacing strategy, run, swim

  9. Diaphragm pacing: the state of the art.

    Science.gov (United States)

    Le Pimpec-Barthes, Francoise; Legras, Antoine; Arame, Alex; Pricopi, Ciprian; Boucherie, Jean-Claude; Badia, Alain; Panzini, Capucine Morelot

    2016-04-01

    Diaphragm pacing (DP) is an orphan surgical procedure that may be proposed in strictly selected ventilator-dependent patients to get an active diaphragm contraction. The goal is to wean from mechanical ventilation (MV) and restore permanent efficient breathing. The two validated indications, despite the lack of randomised control trials, concern patients with high-level spinal cord injuries (SCI) and central hypoventilation syndromes (CHS). To date, two different techniques exist. The first, intrathoracic diaphragm pacing (IT-DP), based on a radiofrequency method, in which the electrodes are directly placed around the phrenic nerve. The second, intraperitoneal diaphragm pacing (IP-DP) uses intradiaphragmatic electrodes implanted through laparoscopy. In both techniques, the phrenic nerves must be intact and diaphragm reconditioning is always required after implantation. No perioperative mortality has been reported and ventilator-weaning rate is about 72% to 96% in both techniques. Improvement of quality of life, by restoring a more physiological breathing, has been almost constant in patients that could be weaned. Failure or delay in recovery of effective diaphragm contractions could be due to irreversible amyotrophy or chest wall damage. Recent works have evaluated the interest of IP-DP in amyotrophic lateral sclerosis (ALS). After some short series were reported in the literature, the only multicentric randomized study including 74 ALS patients was prematurely stopped because of excessive mortality in paced patients. Then, another trial analysed the place of IP-DP in peripheral diaphragm dysfunction but, given the multiple biases, the published results cannot validate that indication. Reviewing all available literature as in our experience, shows that DP is an effective method to wean selected patients dependent on ventilator and improve their daily life. Other potential indications will have to be evaluated by randomised control trials. PMID:27195135

  10. Pace studying worldwide coke production

    International Nuclear Information System (INIS)

    Pace Consultants Inc., Houston, has started a multiclient study of world-wide petroleum coke production, examining environmental initiatives and eventually forecasting prices of fuel grade coke. Pace expects coker expansions, increased operating severity, and reduced cycle times to boost coke supply to more than 50 million metric tons/year in 2000, compared with 39.7 million metric tons in 1992. Increased supply and tightened environmental rules in countries consuming large amounts of petroleum coke will be the main factors affecting coke markets. The paper discusses coke quality and the Japanese market

  11. Aspectos técnicos da cateterização do seio coronariano baseada no componente atrial do eletrograma intracavitário e anatomia radiológica durante o procedimento de implante de marcapasso biventricular Technical aspects of coronary sinus catheterization based on the atrial component of the intracavitary electrogram and radiological anatomy during the implantation procedure of a biventricular pacemaker

    Directory of Open Access Journals (Sweden)

    Fernando Sérgio Oliva de Souza

    2006-04-01

    Full Text Available OBJETIVO: Apresentar uma proposição técnica baseada na experiência de 130 implantes utilizando técnica simplificada para cateterização do seio coronariano, baseada no componente atrial do eletrograma intracavi-tário e anatomia radiológica. MÉTODOS: De outubro de 2001 a outubro de 2004 foram realiza-dos 130 implantes de marcapasso biventricular, utilizando-se anatomia radiológica e observação de eletrograma intracavitário, com prioridade ao componente atrial. RESULTADOS: O implante do sistema, utilizando-se a estimulação do ventrículo esquerdo via seio coronariano, não foi possível em 8 pacientes. Em 12 pacientes foram observadas dificuldades na canulação do óstio coronário e em 15 pacientes observaram-se dificuldades de progressão do eletrodo através do seio coronariano. O tempo médio de utilização de radioscopia foi de 18,69 min. CONCLUSÃO: A técnica de implante, utilizando a morfologia do componente atrial do eletrograma intracavitário e anatomia radiológica, demonstrou ser pouco trabalhosa, segura e eficaz para canulação do óstio do seio coronariano, necessitando de reduzido tempo de radioscopia.OBJECTIVE: To present a technical proposal based on the experience of 130 implantations using a simplified technique for coronary sinus catheterization, based on the atrial component of the intracavitary electrogram and radiological anatomy. METHODS: From October, 2001 to October, 2004, 130 biventricular pacemaker implantations were performed, using radiological anatomy and observation of the intracavitary electrogram, focusing on the atrial component. RESULTS: The implantation of the system using left ventricular pacing via coronary sinus was not possible in 8 patients. Difficulties on the cannulation of the coronary ostium were felt in 12 patients and difficulties of lead advancement through the coronary sinus were felt in 15 patients. The mean time of radioscopy utilization was 18.69 min. CONCLUSION: The

  12. The PACE evaluation: initial findings.

    Science.gov (United States)

    Branch, L G; Coulam, R F; Zimmerman, Y A

    1995-06-01

    As of mid-1994 there were nine replications of the On Lok model operating under dual capitation payments as sites in the Program of All-inclusive Care for the Elderly (PACE). A tenth site had begun operating under capitation, but was unable to remain viable. The present descriptive study documents the growth and development of the first seven of these sites, all that had been operating under capitation during 1992. Comparisons among these sites and with On Lok are presented in the areas of organizational structure, client characteristics, approaches to case management, service delivery options, and financing. There is considerable variability in the implementation of the PACE model. Combined Medicare and Medicaid capitation monthly payments range from $2,147 to $5,973. These seven PACE sites (excluding On Lok) served a total of 888 current clients at the end of 1992, after a cumulative 136 months of experience under capitation. The very slow enrollment rates may imply that the target clients are less enthusiastic about this model than are its architects. The client selection process may suggest niche-marketing or skimming, but not the full representation of the nursing home population in their states. Given both the slow enrollment and the niche-marketing (the benevolent term) or skimming (the pejorative term) that has occurred, caution about the long-term viability of the PACE model may be warranted. PMID:7622088

  13. Low atrial septum pacing in pacemaker patients

    NARCIS (Netherlands)

    Voogt, Willem Gijsbert de

    2006-01-01

    In patients with an indication for anti bradycardia pacing, atrial fibrillation (AF) is a common arrhythmia (30-50%) even in the absence of atrial tachy arrhythmias before pacemaker implantation. Pace prevention and pace intervention for atrial tachy arrhythmias could be an interesting adjuvant trea

  14. A novel association of biventricular cardiac noncompaction and diabetic embryopathy: case report and review of the literature.

    Science.gov (United States)

    Woo, Jennifer S; Perez-Rosendahl, Mari; Haydel, Dana; Perens, Gregory; Fishbein, Michael C

    2015-01-01

    Diabetic embryopathy refers to a constellation of congenital malformations arising in the setting of poorly controlled maternal diabetes mellitus. Cardiac abnormalities are the most frequently observed findings, with a 5-fold risk over normal pregnancies. Although a diverse spectrum of cardiac defects has been documented, cardiac noncompaction morphology has not been associated with this syndrome. In this report, we describe a novel case of biventricular cardiac noncompaction in a neonate of a diabetic mother. The patient was a late preterm female with right anotia, caudal dysgenesis, multiple cardiac septal and aortic arch defects, and biventricular cardiac noncompaction. Examination of both ventricles demonstrated spongy myocardium with increased myocardial trabeculation greater than 50% left ventricular thickness and greater than 75% right ventricular thickness, with hypoplasia of the bilateral papillary muscles, consistent with noncompaction morphology. Review of the literature highlights the importance of gene expression and epigenomic regulation in cardiac embryogenesis. PMID:25386687

  15. ECG Database Applicable for Development and Testing of Pace Detection Algorithms

    Directory of Open Access Journals (Sweden)

    Irena Jekova

    2014-12-01

    Full Text Available This paper presents an ECG database, named 'PacedECGdb' (available at http://biomed.bas.bg/bioautomation/2014/vol_18.4/files/PacedECGdb.zip, which contains different arrhythmias generated by HKP (Heidelberger Praxisklinik simulator, combined with artificially superimposed pacing pulses that cover the wide ranges of rising edge (from <10 µs to 100 µs and total pulse durations (from 100 µs to 2 ms and correspond to various pacemaker modes. It involves a total number of 1404 recordings - 780 representing 'pure' ECG with pacing pulses and 624 that comprise paced ECGs corrupted by tremor. The signals are recorded with 9.81 µV/LSB amplitude resolution at 128 kHz sampling rate in order to preserve the steep raising and trailing edges of the pace pulses. To the best of our knowledge, 'PacedECGdb' is the first publicly available paced ECG database. It could be used for development and testing of methods for pace detection in the ECG. The existence of ECGs corrupted by tremor (the only physiological noise that could compromise the methods for pacing pulses detection is an advantage, since such signals could be applied to define the signal-to-noise level for correct operation of the algorithm, or for improvement of the noise immunity of a method that is under development. The open access of the database makes it suitable for comparative studies including different algorithms.

  16. Pacing the right ventricular outflow tract septum: time to embrace the future.

    Science.gov (United States)

    Hillock, Richard J; Mond, Harry G

    2012-01-01

    Transvenous pacing has revolutionized the management of patients with potentially life-threatening bradycardias and at its most basic level ensures rate support to maintain cardiac output. However, we have known for at least a decade that pacing from the right ventricle (RV) apex can induce left ventricle (LV) dysfunction, atrial fibrillation, heart failure, and maybe an increased mortality. Although pacemaker manufacturers have developed successful pacing algorithms designed to minimize unnecessary ventricular pacing, it cannot be avoided in a substantial proportion of pacemaker-dependent patients. Just as there is undoubted evidence that RV apical pacing is injurious, there is emerging evidence that pacing from the RV septum is associated with a shorter duration of activation, improved haemodynamics, and less LV remodelling. The move from traditional RV apical pacing to RV septal pacing requires a change in mindset for many practitioners. The anatomical landmarks and electrocardiograph features of RV septal pacing are well described and easily recognized. While active fixation is required to place the lead on the septum, shaped stylets are now available to assist the implanter. In addition, concerns about the stability and longevity of steroid-eluting active fixation leads have proven to be unfounded. We therefore encourage all implanters to adopt RV septal pacing to minimize the potential of harm to their patients. PMID:21846639

  17. Effects of gastric pacing on gastric emptying and plasma motilin

    Institute of Scientific and Technical Information of China (English)

    Min Yang; Dian-Chun Fang; Qian-Wei Li; Nian-Xu Sun; Qing-Lin Long; Jian-Feng Sui; Lu Gan

    2004-01-01

    AIM: To invertigate the effects of gastric pacing on gastric emptying and plasma motilin level in a canine model of gastric motility disorders and the correlation between gastric emptying and plasma motilin level.METHODS: Ten healthy Mongrel dogs were divided into:experimental group of six dogs and control group of four dogs. A model of gastric motility disorders was established in the experimental group undergone truncal vagotomy combined with injection of glucagon. Gastric half-emptying time (GEt1/2) was monitored with single photon emission computerized tomography (SPECT), and the half-solid test meal was labeled with an isotope-99m Tc sulfur colloid. Plasma motilin concentration was measured with radioimmunoassay (RIA) kit. Surface gastric pacing at 1.1-1.2 times the intrinsic slow-wave frequency and a superimposed series of high frequency pulses (10-30 Hz) was performed for 45 min daily for a month in conscious dogs.RESULTS: After surgery, GEt1/2 in dogs undergone truncal vagotomy was increased significantly from 56.35±2.99 min to 79.42±l.91 min (P<0.001), but surface gastric pacing markedly accelerated gastric emptying and significantly decreased GEt1/2 to 64,94±l.75 min (P<0.001) in animals undergone vagotomy. There was a significant increase of plasma level of motilin at the phase of IMCⅢ (interdigertive myoelectrical complex, IMCⅢ) in the dogs undergone bilateral truncal vagotomy (baseline vs vagotomy, 184.29±9.81 pg/ml vs 242.09±17,22 pg/ml; P<0.01). But plasma motilin concentration (212.55±11.20 pg/ml; P<0.02) was decreased significantly after a long-term treatment with gastric pacing.Before gastric pacing, GEt1/2 and plasma motilin concentration of the dogs undergone vagotomy showed a positive correlation (r=0.867, P<0.01), but after a long-term gastric pacing, GEt1/2 and motilin level showed a negative correlation (r=-0.733, P<0,04).CONCLUSION: Surface gastric pacing with optimal pacing parameters can improve gastric emptying

  18. Biventricular noncompaction presented with symptomatic complete heart block – Report of a case and review of literature

    OpenAIRE

    Patra, Soumya; Kumar, Basant; Sadananda, Kanchanahalli Siddegowda; Basappa, Harsha; Nanjappa, Manjunath Cholenahally

    2013-01-01

    Ventricular noncompaction has been recognized as a distinct form of rare cardiomyopathy characterized by numerous, prominent ventricular trabeculations and deep intertrabecular recesses and is caused by a disorder of endomyocardial morphogenesis. Concomitance of either valvular pathologies or complete atrioventricular block with biventricular noncompaction has rarely been reported. Herein, we present a case of 67 years old male presented with syncopal attack and congestive heart failure due t...

  19. Biventricular Finite Element Modeling of the Acorn CorCap Cardiac Support Device on a Failing Heart

    OpenAIRE

    Wenk, JF; L. Ge; Zhang, Z; Mojsejenko, D; Potter, DD; Tseng, EE; Guccione, JM; Ratcliffe, MB

    2013-01-01

    Background: The Acorn CorCap Cardiac Support Device (CSD; Acorn Cardiovascular Inc, St. Paul, MN) is a woven polyester jacket that is placed around the heart and designed to reverse the progressive remodeling associated with dilated cardiomyopathy. However, the effects of the Acorn CSD on myofiber stress and ventricular function remain unknown. We tested the hypothesis that the Acorn CSD reduces end-diastolic (ED) myofiber stress. Methods: A previously described weakly coupled biventricular f...

  20. Gait coordination after stroke: Benefits of acoustically paced treadmill walking

    NARCIS (Netherlands)

    Roerdink, Melvyn; Lamoth, Claudine J.C.; Kwakkel, Gert; Van Wieringen, Piet C.W.; Beek, Peter J.

    2007-01-01

    Background and Purpose: Gait coordination often is compromised after stroke. The purpose of this study was to evaluate the efficacy of acoustically paced treadmill walking as a method for improving gait coordination in people after stroke. Participants: Ten people after stroke volunteered for the st

  1. Gait coordination after stroke: benefits of acoustically paced treadmill walking.

    NARCIS (Netherlands)

    Roerdink, M.; Lamoth, C.J.; Kwakkel, G.; Wieringen, P.C. van; Beek, P.J.

    2007-01-01

    BACKGROUND AND PURPOSE: Gait coordination often is compromised after stroke. The purpose of this study was to evaluate the efficacy of acoustically paced treadmill walking as a method for improving gait coordination in people after stroke. PARTICIPANTS: Ten people after stroke volunteered for the st

  2. Gastrointestinal bleeding in a patient with a continuous-flow biventricular assist device

    Science.gov (United States)

    Mirasol, Raymond V; Tholany, Jason J; Reddy, Hasini; Fyfe-Kirschner, Billie S; Cheng, Christina L; Moubarak, Issam F; Nosher, John L

    2016-01-01

    The association between continuous-flow left ventricular assist devices (CF-LVADs) and gastrointestinal (GI) bleeding from angiodysplasia is well recognized. However, the association between continuous-flow biventricular assist devices (CF-BIVADs) and bleeding angiodysplasia is less understood. We report a case of GI bleeding from a patient with a CF-BIVAD. The location of GI bleeding was identified by nuclear red blood cell bleeding scan. The vascular malformation leading to the bleed was identified and localized on angiography and then by pathology. The intensity of bleeding, reflected by number of units of packed red blood cells needed for normalization of hemoglobin, as well as the time to onset of bleeding after transplantation, are similar to that seen in the literature for CF-LVADs and pulsatile BIVADs. While angiography only detected a dilated late draining vein, pathology demonstrated the presence of both arterial and venous dilation in the submucosa, vascular abnormalities characteristic of a late arteriovenous malformation. PMID:27158430

  3. Numerical Simulation of a Biventricular Assist Device with Fixed Right Outflow Cannula Banding During Pulmonary Hypertension.

    Science.gov (United States)

    Nadeem, K; Ng, B C; Lim, E; Gregory, S D; Salamonsen, R F; Stevens, M C; Mubin, M; Lovell, N H

    2016-04-01

    As a left ventricular assist device is designed to pump against the systemic vascular resistance (SVR), pulmonary congestion may occur when using such device for right ventricular support. The present study evaluates the efficacy of using a fixed right outflow banding in patients receiving biventricular assist device support under various circulatory conditions, including variations in the SVR, pulmonary vascular resistance (PVR), total blood volume (BV), as well as ventricular contractility. Effect of speed variation on the hemodynamics was also evaluated at varying degrees of PVR. Pulmonary congestion was observed at high SVR and BV. A reduction in right ventricular assist device (RVAD) speed was required to restore pulmonary pressures. Meanwhile, at a high PVR, the risk of ventricular suction was prevalent during systemic hypotension due to low SVR and BV. This could be compensated by increasing RVAD speed. Isolated right heart recovery may aggravate pulmonary congestion, as the failing left ventricle cannot accommodate the resultant increase in the right-sided flow. Compared to partial assistance, the sensitivity of the hemodynamics to changes in VAD speed increased during full assistance. In conclusion, our results demonstrated that the introduction of a banding graft with a 5 mm diameter guaranteed sufficient reserve of the pump speed spectrum for the regulation of acceptable hemodynamics over different clinical scenarios, except under critical conditions where drug administration or volume management is required. PMID:26173771

  4. A sheep survived for 48 days with the biventricular bypass type total artificial heart.

    Directory of Open Access Journals (Sweden)

    Senoo,Yoshimasa

    1991-08-01

    Full Text Available A biventricular bypass type total artificial heart (BVB-TAH utilizing two pusher-plate pumps was developed and implanted in a sheep for 48 days with excellent results. A Hall effect sensor was utilized to operate each pump independently with a full stroke at variable rates (VR. With this system, the animal's hemodynamics was kept physiologically, and all metabolic parameters except hemoglobin and hematocrit returned to normal three weeks after implantation. However, signs of infection appeared on the forty-second day, and consequently the animal fell into a state of shock. Even at that time the BVB-TAH maintained circulation by increasing pumping rate automatically. On the forty-eighth day, the animal could not stand and suffered from anuria; the experiment was then terminated after 1,140 h pumping. At autopsy, there was an enlarged heart with an atrophic change, 1,900 ml of pleural effusion, and 3,100ml of ascites fluid. Blood culture taken on the forty-seventh day yielded Acinetobacter calcoaceticus. The BVB-TAH operated in an independent VR mode maintained entire circulation, and has a capability of substituting the native heart function in any situation.

  5. In-vivo motion analysis of bi-ventricular hearts from tagged MR images

    Science.gov (United States)

    Park, Kyoungju; Axel, Leon; Metaxas, Dimitris N.

    2005-04-01

    We conduct experiments to look at the in-vivo cardiac motion during systole, to visualize heart contraction, and to examine the clinical usefulness. Our model-based technique incorporates subject-specific modeling, motion analysis and the extraction of clinically relevant parameters within one framework. Previous bi-ventricular model based method could only handle up to the mid-ventricles and have a few test-subjects. Our parameterized model includes the LV, RV and up to the basal area for full ventricular motion study. Finite element methods capture cardiac motion by tracking the material points from tagged Magnetic Resonance (MR) images. A number of experiments from ten subjects are evaluated and analyzed. We tested subject several times and compared the resulting parameters to ensure the reproducibility and deviations. The resulting parameters can be used to describe the cardiac motion of normal subjects. The patterns of normal subjects were derived from experiments. While significant shape and motion variations were apparent in normal subjects, the quantitative analysis show typical patterns. Generally, the basal area moves downwards and the apical area contracts towards the cavity. The principal strain analysis describes the directions and magnitudes of maximum shortening, and maximum thickening.

  6. Low atrial septum pacing in pacemaker patients

    OpenAIRE

    Voogt, Willem Gijsbert de

    2006-01-01

    In patients with an indication for anti bradycardia pacing, atrial fibrillation (AF) is a common arrhythmia (30-50%) even in the absence of atrial tachy arrhythmias before pacemaker implantation. Pace prevention and pace intervention for atrial tachy arrhythmias could be an interesting adjuvant treatment in the prevention of the arrhythmia related complications. These treatment modalities when available in pacemaker systems could come at a relative low cost as the indication for pacemaker imp...

  7. Ventilation patterns mimicking COPD in patients with diaphragmatic pacing for Ondine's curse

    International Nuclear Information System (INIS)

    Ventilation was studied with 133Xe in 18 patients with central hypoventilation (Ondine's Curse) in whom diaphragmatic pacers were implanted. Three distinct patterns emerged: Type I, improvement in ventilation on the paced side (11 of 18 patients); Type II, improvement on both the paced and unpaced side (4 of 18); and Type III, no improvement (3 of 18). With the pacer off, many of these patients have patterns that mimic chronic obstructive pulmonary disease and that revert to normal with pacing. This retention, clearly reversible, cannot reflect permanent airways or airspace disease

  8. Optimal implantation depth and adherence to guidelines on permanent pacing to improve the results of transcatheter aortic valve replacement with the medtronic corevalve system: The CoreValve prospective, international, post-market ADVANCE-II study

    OpenAIRE

    Petronio, Anna S; Sinning, Jan-Malte; Van Mieghem, Nicolas; Zucchelli, Giulio; Nickenig, Georg; Bekeredjian, Raffi; Bosmans, B.; Bedogni, Francesco; Branny, Marian; Stangl, Karl; Kovac, Jan; Schiltgen, Molly; Kraus, Stacia; De Jaegere, Peter

    2015-01-01

    textabstractObjectives The aim of the CoreValve prospective, international, post-market ADVANCE-II study was to define the rates of conduction disturbances and permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement with the Medtronic CoreValve System (Minneapolis, Minnesota) using optimized implantation techniques and application of international guidelines on cardiac pacing. Background Conduction disturbances are a frequent complication of transcatheter aortic va...

  9. Web Tools: Keeping Learners on Pace

    Science.gov (United States)

    Kosloski, Mickey

    2016-01-01

    One of the greatest challenges in teaching technology and engineering is pacing. Some students grasp new technological concepts quickly, while others need repetition and may struggle to keep pace. This poses an obstacle for the technology and engineering teacher, and is particularly true when teaching students to build a website. However, there…

  10. Normalisation of left ventricular systolic function after change from VVI pacing to biventricular pacing in a child with congenital complete atrioventricular block, long-QT syndrome, and congenital muscular dystrophy

    DEFF Research Database (Denmark)

    Ellesøe, Sabrina Gade; Reimers, Jesper Irving; Andersen, Henrik Ø

    2014-01-01

    Development of dilated cardiomyopathy in patients with congenital complete atrioventricular block with or without pacemaker is well described. We report a case of dilated cardiomyopathy in a child with congenital complete atrioventricular block, long-QT syndrome, and VVI pacemaker. Temporary paci...

  11. The pace of cultural evolution.

    Directory of Open Access Journals (Sweden)

    Charles Perreault

    Full Text Available Today, humans inhabit most of the world's terrestrial habitats. This observation has been explained by the fact that we possess a secondary inheritance mechanism, culture, in addition to a genetic system. Because it is assumed that cultural evolution occurs faster than biological evolution, humans can adapt to new ecosystems more rapidly than other animals. This assumption, however, has never been tested empirically. Here, I compare rates of change in human technologies to rates of change in animal morphologies. I find that rates of cultural evolution are inversely correlated with the time interval over which they are measured, which is similar to what is known for biological rates. This correlation explains why the pace of cultural evolution appears faster when measured over recent time periods, where time intervals are often shorter. Controlling for the correlation between rates and time intervals, I show that (1 cultural evolution is faster than biological evolution; (2 this effect holds true even when the generation time of species is controlled for; and (3 culture allows us to evolve over short time scales, which are normally accessible only to short-lived species, while at the same time allowing for us to enjoy the benefits of having a long life history.

  12. Pollution Abatement and Control Expenditures Survey (PACE)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Pollution Abatement Costs and Expenditures (PACE) survey is the most comprehensive national source of pollution abatement costs and expenditures related to...

  13. Cardiac pacing in pediatrics: Is still the right ventricle the optimal pacing site?

    Directory of Open Access Journals (Sweden)

    Michel Cabrera Ortega

    2015-10-01

    Full Text Available Permanent cardiac pacing is frequently indicated in pediatric patients due to atrioventricular block. Traditionally, the right ventricle has been the pacing site because it is readily accessible, and provides lead stability and optimal chronic pacing thresholds. However, it is associated with a dyssynchrony pattern of ventricular activation, that may cause remodeling and impairment of left ventricular function. In pediatric patients, paced from an early age and with a long life expectancy, the preservation of cardiac function is a premise. Therefore, the prevention of dyssynchrony, using possible alternative sites, is not just a priority, is a challenge. The aim of the article is to show the effects of chronic right ventricular pacing as well as the evidence of benefits provided by alternatives pacing sites in pediatric population and their clinical and practical implications.

  14. Optogenetic pacing in Drosophila melanogaster (Conference Presentation)

    Science.gov (United States)

    Alex, Aneesh; Li, Airong; Men, Jing; Jerwick, Jason; Tanzi, Rudolph E.; Zhou, Chao

    2016-03-01

    A non-invasive, contact-less cardiac pacing technology can be a powerful tool in basic cardiac research and in clinics. Currently, electrical pacing is the gold standard for cardiac pacing. Although highly effective in controlling the cardiac function, the invasive nature, non-specificity to cardiac tissues and possible tissue damage limits its capabilities. Optical pacing of heart is a promising alternative, which is non-invasive and more specific, has high spatial and temporal precision, and avoids shortcomings in electrical stimulation. Optical coherence tomography has been proved to be an effective technique in non-invasive imaging in vivo with ultrahigh resolution and imaging speed. In the last several years, non-invasive specific optical pacing in animal hearts has been reported in quail, zebrafish, and rabbit models. However, Drosophila Melanogaster, which is a significant model with orthologs of 75% of human disease genes, has rarely been studied concerning their optical pacing in heart. Here, we combined optogenetic control of Drosophila heartbeat with optical coherence microscopy (OCM) technique for the first time. The light-gated cation channel, channelrhodopsin-2 (ChR2) was specifically expressed by transgene as a pacemaker in drosophila heart. By stimulating the pacemaker with 472 nm pulsed laser light at different frequencies, we achieved non-invasive and more specific optical control of the Drosophila heart rhythm, which demonstrates the wide potential of optical pacing for studying cardiac dynamics and development. Imaging capability of our customized OCM system was also involved to observe the pacing effect visually. No tissue damage was found after long exposure to laser pulses, which proved the safety of optogenetic control of Drosophila heart.

  15. Diagnostic accuracy of pace spikes in the electrocardiogram to diagnose paced rhythm

    DEFF Research Database (Denmark)

    Andersson, Hedvig; Hansen, Marco Bo; Thorsberger, Mads; Biering-Sørensen, Tor; Nielsen, Jonas Bille; Graff, Claus; Pehrson, Steen; Svendsen, Jesper Hastrup

    2015-01-01

    sensitivity of manual ECG interpretation for pace spikes was low for atrial pacing (Reader 1: 0.62 [95% confidence interval (CI) 0.50-0.74]; Reader 2: 0.65 [95% CI 0.53-0.77]) and moderate for ventricular pacing (Reader 1: 0.88 [95% CI 0.81-0.93]; Reader 2: 0.93 [95% CI 0.87-0.97]). CONCLUSIONS: In patients...

  16. An Undergraduate Intern Program at PACES

    Science.gov (United States)

    Starks, Scott A.

    1997-01-01

    The University of Texas at El Paso (UTEP) established the Pan American Center for Earth and Environmental Studies (PACES) in 1995 to conduct basic and applied research that contributes to NASA's Mission to Planet Earth. Specifically, PACES provides a repository of remote sensing and other information that supports investigations into an improved understanding of geological, ecological and environmental processes occurring in the southwestern United States and Northern Mexico. Approximately 85% of UTEP's students come from El Paso County, a fast growing urban region representative of many large cities in the Southwest that have, or will soon have, a majority of their population composed of groups currently underrepresented in the scientific and technical workforce. UTEP's student population has an ethnic distribution (63% Hispanic, 32% Anglo, 3% African American, 1.5 % Asian American, and less than 1% Native American) that closely matches the demographics of the region it serves. Thus, UTEP has a mission to serve a multicultural population where minority students comprise the majority. Most Hispanic students at UTEP are primarily of Mexican origin. A large number are first or second-generation U.S. citizens. Characteristics that unite Hispanic students, in particular those of Mexican-origin, are a strong sense of family loyalty and a belief that all family members are responsible for contributing to the economic stability and well-being of the family. Most of their families are larger in number than the national average, and a variety of generations live together or share considerable resources. Thus, many young people feel an obligation and a desire to go to work at a young age and to continue working while in college, thereby assisting their parents and other family members. Older siblings understand that they have responsibilities to do household chores, to aid their younger siblings economically, and to assist elderly family members. This "work ethic" within the

  17. Synchronous intra-myocardial ventricular pacing without crossing the tricuspid valve or entering the coronary sinus

    Energy Technology Data Exchange (ETDEWEB)

    Konecny, Tomas; DeSimone, Christopher V.; Friedman, Paul A.; Bruce, Charles [Department of Medicine, Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Asirvatham, Samuel J., E-mail: asirvatham.samuel@mayo.edu [Department of Medicine, Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Department of Pediatric and Adolescent Medicine, Pediatric Cardiology, Mayo Clinic, Rochester, MN (United States)

    2013-05-15

    Ventricular pacing is most commonly performed at the right ventricular (RV) apex. This is not without risk as placement requires crossing the tricuspid valve (TV) and may cause valvular dysfunction and dyssynchronous activation of the ventricles. The fact that the tricuspid valve lies more apically than the mitral valve allows for the possibility of pacing the ventricles from the right atrium (RA) via the “atrio-ventricular septum” without crossing the TV or entering the coronary sinus (CS). In order to mitigate far field activation inherent to current pacing technology, we constructed a novel lead in which the cathode and anode are both intra-myocardial. We demonstrate safety and efficacy of this novel lead for ventricular pacing at the atrio-ventricular septum in canines, including improved synchronous activation of both ventricles, improved differentiation in ventricular versus atrial sensing, while providing reliable ventricular capture, opening novel and a potentially safer alternative to human cardiac resynchronization therapy.

  18. 42 CFR 460.60 - PACE organizational structure.

    Science.gov (United States)

    2010-10-01

    ... planning a change in organizational structure must notify CMS and the State administering agency, in... 42 Public Health 4 2010-10-01 2010-10-01 false PACE organizational structure. 460.60 Section 460... ELDERLY (PACE) PACE Administrative Requirements § 460.60 PACE organizational structure. (a) A...

  19. No incremental benefit of multisite atrial pacing compared with right atrial pacing in patients with drug refractory paroxysmal atrial fibrillation

    OpenAIRE

    Levy, T; Walker, S; Rex, S; Rochelle, J; Paul, V.

    2001-01-01

    OBJECTIVE—To evaluate the incremental antifibrillatory effect of multisite atrial pacing compared with right atrial pacing in patients with drug refractory paroxysmal atrial fibrillation paced for arrhythmia prevention alone.
METHODS—In 20 of these patients (mean (SD) age 64 (8) years; 14 female, six male), a single blinded randomised crossover study was performed to investigate the incremental benefit of one month of multisite atrial pacing compared with one month of right atrial pacing. Out...

  20. EFFECT OF ADAPTIVE PACED CARDIOLOCOMOTOR SYNCHRONIZATION DURING RUNNING: A PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    Bill Phillips

    2013-09-01

    Full Text Available Cardiolocomotor synchronization (CLS has been well established for individuals engaged in rhythmic activity, such as walking, running, or cycling. When frequency of the activity is at or near the heart rate, entrainment occurs. CLS has been shown in many cases to improve the efficiency of locomotor activity, improving stroke volume, reducing blood pressure variability, and lowering the oxygen uptake (VO2. Instead of a 1:1 frequency ratio of activity to heart rate, an investigation was performed to determine if different harmonic coupling at other simple integer ratios (e.g. 1:2, 2:3, 3:2 could achieve any performance benefits. CLS was ensured by pacing the stride rate according to the measured heartbeat (i.e., adaptive paced CLS, or forced CLS. An algorithm was designed that determined the simplest ratio (lowest denominator that, when multiplied by the heart rate will fall within an individualized, predetermined comfortable pacing range for the user. The algorithm was implemented on an iPhone 4, which generated a 'tick-tock' sound through the iPhone's headphones. A sham-controlled crossover study was performed with 15 volunteers of various fitness levels. Subjects ran a 3 mile (4.83 km simulated training run at their normal pace on two consecutive days (randomized one adaptive pacing, one sham. Adaptive pacing resulted in faster runs run times, with subjects running an average of 26:03 ± 3:23 for adaptive pacing and 26:38 ± 3:31 for sham (F = 5.46, p < 0.05. The increase in heart rate from the start of the race as estimated by an exponential time constant was significantly longer during adaptive pacing, τ = 0.99 ± 0.30, compared to sham, τ = 1.53 ± 0.34 (t = -6.62, p < 0.01. Eighty-seven percent of runners found it easy to adjust their stride length to match the pacing signal with seventy-nine percent reporting that pacing helped their performance. These results suggest that adaptive paced CLS may have a beneficial effect on running

  1. Pajarito Aerosol Couplings to Ecosystems (PACE) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, M [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-01

    Laboratory (LANL) worked on the Pajarito Aerosol Couplings to Ecosystems (PACE) intensive operational period (IOP). PACE’s primary goal was to demonstrate routine Mobile Aerosol Observing System (MAOS) field operations and improve instrumental and operational performance. LANL operated the instruments efficiently and effectively with remote guidance by the instrument mentors. This was the first time a complex suite of instruments had been operated under the ARM model and it proved to be a very successful and cost-effective model to build upon.

  2. Visual aided pacing in respiratory maneuvers

    Energy Technology Data Exchange (ETDEWEB)

    Rambaudi, L R [Laboratorio de Biofisica y Fisiologia ' Antonio Sadi Frumento' (Argentina); Rossi, E [Catedra de Bioingenieria II (Argentina); Mantaras, M C [Catedra de Bioingenieria II (Argentina); Perrone, M S [Laboratorio de Biofisica y Fisiologia ' Antonio Sadi Frumento' (Argentina); Siri, L Nicola [Catedra de Bioingenieria II (Argentina)

    2007-11-15

    A visual aid to pace self-controlled respiratory cycles in humans is presented. Respiratory manoeuvres need to be accomplished in several clinic and research procedures, among others, the studies on Heart Rate Variability. Free running respiration turns to be difficult to correlate with other physiologic variables. Because of this fact, voluntary self-control is asked from the individuals under study. Currently, an acoustic metronome is used to pace respiratory frequency, its main limitation being the impossibility to induce predetermined timing in the stages within the respiratory cycle. In the present work, visual driven self-control was provided, with separate timing for the four stages of a normal respiratory cycle. This visual metronome (ViMet) was based on a microcontroller which power-ON and -OFF an eight-LED bar, in a four-stage respiratory cycle time series handset by the operator. The precise timing is also exhibited on an alphanumeric display.

  3. Visual aided pacing in respiratory maneuvers

    International Nuclear Information System (INIS)

    A visual aid to pace self-controlled respiratory cycles in humans is presented. Respiratory manoeuvres need to be accomplished in several clinic and research procedures, among others, the studies on Heart Rate Variability. Free running respiration turns to be difficult to correlate with other physiologic variables. Because of this fact, voluntary self-control is asked from the individuals under study. Currently, an acoustic metronome is used to pace respiratory frequency, its main limitation being the impossibility to induce predetermined timing in the stages within the respiratory cycle. In the present work, visual driven self-control was provided, with separate timing for the four stages of a normal respiratory cycle. This visual metronome (ViMet) was based on a microcontroller which power-ON and -OFF an eight-LED bar, in a four-stage respiratory cycle time series handset by the operator. The precise timing is also exhibited on an alphanumeric display

  4. Social marketing of a different pace

    OpenAIRE

    Kamin, Tanja

    2015-01-01

    This article examines social marketing as one of the approaches for managing social change. We place the concept of social marketing on the continuum between liberal and paternalistic approaches to social change management. Furthermore, we consider which forms of social change management in Slovenia are dominant, and in which position among them is social marketing. The presumption of the discussion is that social marketing has developed at different paces and with different acknowledgements ...

  5. Application of PACE Principles for Population Health Management of Frail Older Adults.

    Science.gov (United States)

    Stefanacci, Richard G; Reich, Shelley; Casiano, Alex

    2015-10-01

    To determine which practices would have the most impact on reducing hospital and emergency department admissions and nursing home placement among older adults with multiple comorbid conditions, a literature search and survey were conducted to identify and prioritize comprehensive care principles as practiced in the Program of All-inclusive Care for the Elderly (PACE). PACE medical directors and members of the PACE interdisciplinary team (IDT) were surveyed to gain their insights on the most impactful practices, which were identified as: End-of-Life Management, Caregiver Support, Management of Red Flags, Medication Management, Participant and Caregiver Health Care System Literacy, and Care Coordination. In addition, this research evaluated measures that could be used to assess an organization's level of success with regard to each of the 6 PACE practices identified. The results reported in this article, found through a survey with PACE medical directors and IDT members concerning effective interventions, can be viewed as strategies to improve care for older adults, enabling them to maintain their independence in the community, avoid the expense of facility-based care, and enhance their quality of life. PMID:25647691

  6. Aliskiren protecting atrial structural remodeling from rapid atrial pacing in a canine model.

    Science.gov (United States)

    Zhao, Zhiqiang; Chen, Yan; Li, Weimin; Wang, Xinghua; Li, Jian; Yang, Wansong; Cheng, Lijun; Liu, Tong; Liu, Enzhao; Li, Guangping

    2016-08-01

    Atrial fibrillation (AF) contributing to the increasing mortality risk is the most common disease in clinical practice. Owing to the side effects and relative inefficacy of current antiarrhythmic drugs, some research focuses on renin-angiotensin-aldosterone system (RAS) for finding out the new treatment of AF. The purpose of this study is to confirm whether aliskiren as a proximal inhibitor of renin, which completely inhibits RAS, has beneficial effects on atrial structural remodeling in AF. In this study, rapid atrial pacing was induced at 500 beats per minute for 2 weeks in a canine model. A different dose of aliskiren was given orally for 2 weeks before rapid atrial pacing. HE staining and Masson's staining were used for analysis of myocardial fibrosis. TGF-β1, signal pathways, and pro-inflammatory cytokines were shown for the mechanism of structural remodeling after the treatment of aliskiren. Serious atrial fibrosis was induced by rapid atrial pacing, followed by the elevated TGF-β1, upregulated MEK and ERK1/2, and increased inflammatory factors. Aliskiren could apparently improve myocardial fibrosis by reducing the expression of TGF-β1, inhibiting MEK and ERK1/2 signal pathways, and decreasing IL-18 and TLR4 in both serum and atrial tissue. In conclusion, aliskiren could prevent atrial structural remodeling from rapid atrial pacing for 2 weeks. Aliskiren may play a potential beneficial role in the treatment of AF induced by rapid atrial pacing. PMID:27118660

  7. Self-Paced Multi-Task Learning

    OpenAIRE

    Li, Changsheng; Wei, Fan; Yan, Junchi; Dong, Weishan; Liu, Qingshan; Zha, Hongyuan

    2016-01-01

    In this paper, we propose a novel multi-task learning (MTL) framework, called Self-Paced Multi-Task Learning (SPMTL). Different from previous works treating all tasks and instances equally when training, SPMTL attempts to jointly learn the tasks by taking into consideration the complexities of both tasks and instances. This is inspired by the cognitive process of human brain that often learns from the easy to the hard. We construct a compact SPMTL formulation by proposing a new task-oriented ...

  8. Influence of cinnamon and catnip on the stereotypical pacing of oncilla cats (Leopardus tigrinus) in captivity.

    Science.gov (United States)

    Resende, Letícia de S; Pedretti Gomes, Karla C; Andriolo, Artur; Genaro, Gelson; Remy, Gabriella L; Almeida Ramos, Valdir de

    2011-01-01

    Nonhuman animals in captivity can experience environmental privation that results in their exhibiting abnormal behaviors. Environmental enrichment techniques can help improve their welfare. This study investigated the behavior of 8 zoo-housed oncilla cats (Leopardus tigrinus) in response to 2 odors (catnip and cinnamon) introduced individually into the animals' enclosures for 3 consecutive days. Proportion of scans spent engaging in stereotypical pacing were compared before, during, and after treatments. The addition of cinnamon reduced the proportion of pacing during and after enrichment (Wilcoxon: Z = 3.16, p behavior. Catnip appears to have elicited no significant difference in the stereotypic pacing before, during, or after the enrichment (Friedman: X(2) = 2.69; p = .260). The results highlight the potential use of cinnamon as a method of environmental enrichment for small captive-housed cats. PMID:22044295

  9. Costs and Outcomes in the Care of Bi-ventricular Support as a Bridge to Cardiac Transplant.

    Science.gov (United States)

    Swartz, Michael F; Angona, Ron; Smith, Karen; Kraenzlin, Franca; Stypula, Christine M; Joshi, Devang; Tchantchaleishvili, Vakhtang; Hicks, George L; Massey, H Todd

    2016-01-01

    Bi-ventricular (Bi-V) mechanical circulatory support is commonly used as a bridge to cardiac transplant. However, the optimal strategy is unknown. We examined the outcomes, as well as the costs in the use of Bi-V support as a bridge to cardiac transplant. From 2001 to 2014, three different Bi-V support strategies were utilized: 1) Para-corporeal ventricular assist device (PVAD-2001-2006), 2) Heartmate II left ventricular assist device in conjunction with a temporary CentriMag right ventricular assist device (HMII + CMAG-2006-2012), and the total artificial heart (TAH-2012-2014). Total costs were derived from the hospitalization at implant, and postimplant costs defined as equipment and re-hospitalizations before transplantation. Sixty-five (34 PVADs, 20 HMII + CMAG, and 11 TAHs) devices were used as a bridge for transplant. There were no differences in implant variables including age, INTERMACS score, or implant length of stay. Although the wait list mortality was not different between groups (PVAD-32%, HMII + CMAG-45%, TAH-54%; p = 0.3), the percentage of patients transplanted were highest in the PVAD group: (PVAD-55.8%, HMII + CMAG-30.0%, TAH-18.2%; p = 0.01). Total costs were not significantly different between groups (PVAD-$306,166 ± 247,839, HMII + CMAG-$278,958 ± 135,324, TAH-$321,387 ± 21,2477; p = 0.5). Despite variations in therapy, outcomes and costs for patients requiring Bi-V support as a bridge to cardiac transplant have remained constant. PMID:27258229

  10. Redistribution of myocardial perfusion during permanent dual chamber pacing in symptomatic non-obstructive hypertrophic cardiomyopathy : A quantitative positron emission tomography study

    NARCIS (Netherlands)

    Posma, JL; Blanksma, PK; vanderWall, EE

    1996-01-01

    Dual chamber pacing causes significant symptomatic improvement in many patients with hypertrophic cardiomyopathy. The mechanism behind this beneficial response is not fully understood. Positron emission tomography showed a redistribution of myocardial flow during pacing in a patient with non-obstruc

  11. Pacing: A Concept Analysis of a Chronic Pain Intervention

    OpenAIRE

    Jamieson-Lega, Kathryn; Berry, Robyn; Brown, Cary A.

    2013-01-01

    BACKGROUND: The intervention of pacing is regularly recommended for chronic pain patients. However, pacing is poorly defined and appears to be interpreted in varying, potentially contradictory manners within the field of chronic pain. This conceptual lack of clarity has implications for effective service delivery and for researchers’ ability to conduct rigorous study. An examination of the background literature demonstrates that while pacing is often one part of a multidisciplinary pain manag...

  12. Right Ventricular Septal Pacing: Has it come of age?

    Directory of Open Access Journals (Sweden)

    Johnson Francis

    2010-02-01

    Full Text Available Prolonged pacing from the right ventricular (RV apex has been shown to be associated with progressive left ventricular dysfunction as demonstrated by heart failure, atrial fibrillation and an increased morbidity and mortality [1-6]. This has led to an interest in alternate RV pacing sites and in particular the mid RV septum and the RV outflow tract (RVOT septum [7-11]. These sites are theoretically associated with a more physiological ventricular activation. Despite the perceived advantages of septal pacing, results to date are not confirmatory [12-18]. These studies were generally acute or extended to 6-months and the leads secured to the RVOT and thus were not necessarily septal. On review of the early work of Durrer et al in 1970 [19] the septal regions of the RVOT and mid RV are the first zones of the ventricle to depolarize, suggesting that pacing from these areas on the right side of the septum would achieve as normal a contraction pattern as possible. In contrast, the free wall of the RV is the last zone to be depolarized. When attempting to prove the physiologic and hemodynamic benefits of septal pacing, it seems illogical to choose the RVOT with a mix of both septal and free wall pacing. The potential benefits of septal pacing would possibly be negated by free wall pacing and thus it is not surprising that there has been no consistent benefit over RV apical pacing demonstrated.

  13. Chronic in ovo hypoxia decreases pulmonary arterial contractile reactivity and induces biventricular cardiac enlargement in the chicken embryo.

    Science.gov (United States)

    Villamor, Eduardo; Kessels, Carolina G A; Ruijtenbeek, Karin; van Suylen, Robert J; Belik, Jaques; de Mey, Jo G R; Blanco, Carlos E

    2004-09-01

    arteries, and induced biventricular cardiac hypertrophy. PMID:15117730

  14. Effect of atrial pacing therapy with selective pacing algorithms on paroxysmal atrial fibrillation

    Institute of Scientific and Technical Information of China (English)

    潘晓宏; 张雪华; 徐耕; 傅国胜; 单江

    2004-01-01

    @@ Atrial fibrillation (AF) is the most common cardiac arrhythmia among the elderly. Its incidence increases dramatically with increasing age and decreasing left ventricular function, peaking in subjects with overt congestive heart failure.1 Because of the unsatisfactory efficacy and possible serious side effects of clinically available anti-AF drugs for AF patients with sick sinus syndrome, pacing techniques have recently been applied in the treatment of AF. The cardiac pacemaker Vitatron Selection 900E has special AF diagnostic and prophylactic therapy algorithms. The objective of this study was to use the diagnostic information concerning the onset mechanisms of AF to program the preventive pacing algorithms for each patient individually and to find out whether a reduction in AF burden could be achieved.

  15. Specific Intensity for Peaking: Is Race Pace the Best Option?

    Directory of Open Access Journals (Sweden)

    Munoz

    2015-09-01

    Full Text Available Background The peaking period for endurance competition is characterized for a relative increase of the intensity of training, after a longer period of training relatively dominated by lower intensity and higher volume Objectives The present study was designed to compare physiological and 10 km performance effects of high intensity training (HIT versus race pace interval training (RP during peaking for competition in well-trained runners. Patients and Methods 13 athletes took part in the study, they were divided into two groups: HIT and RP. HIT performed short intervals at ~105% of the maximal aerobic velocity (MAV, while RP trained longer intervals at a speed of ~90% of the MAV (a speed approximating 10 km race pace. After 12 weeks of baseline training, the athletes trained for 6 weeks under one of the two peaking regimes. Subjects performed 10 km prior to and after the intervention period. The total load of training was matched between groups during the treatment phase. Subjects completed a graded treadmill running test until volitional exhaustion prior to each 10 km race. MAV was determined as the minimal velocity eliciting maximal oxygen consumption (VO2max. Results Both groups significantly improved their 10 km time (35 minutes 29 seconds ± 1 minutes 41 seconds vs 34 minutes 53 seconds ± 1 minutes 55 seconds, P 0.05. In contrast, running economy decreased significantly after HIT (210 ± 6 ml.Kg-1.km-1 vs 218 ± 9, P < 0.05. Conclusions A 6 week period of training at either 105% of MAV or 90% of MAV yielded similar performance gains in a 10km race performed at ~90% MAV. Therefore, the physiological impact of HIT training seems to be positive for VO2max but negative for running economy.

  16. PACE3 - front-end chip for the CMS Preshower

    CERN Multimedia

    Aspel, Paul

    2003-01-01

    This is PACE3 which is the front-end chip for the CMS Preshower. In fact PACE3 is the combination of two ASICs called Delta3 and PACEAM3. Delta3 is on the left and PACEAM3 is on the right. The two ASICs are bonded together and then packaged within a single 196 pin fpBGA package.

  17. Social Interaction in Self-Paced Distance Education

    Science.gov (United States)

    Anderson, Terry; Upton, Lorne; Dron, Jon; Malone, Judi; Poelhuber, Bruno

    2015-01-01

    In this paper we present a case study of a self-paced university course that was originally designed to support independent, self-paced study at distance. We developed a social media intervention, in design-based research terms, that allows these independent students to contribute archived content to enhance the course, to engage in discussions…

  18. Temporary emergency pacing-an orphan in district hospitals

    DEFF Research Database (Denmark)

    Gjesdal, Knut; Johansen, Jens Brock; Gadler, Fredrik

    2012-01-01

    This editorial discusses a report on the 1 year experience with temporary pacing, especially in the emergency setting, in several Norwegian district hospitals. The vast majority of the patients received transvenous temporary pacing, and the majority of leads were placed by noncardiologists. The p...

  19. The KN-3000 particle accelerator control expert system (PACES)

    International Nuclear Information System (INIS)

    The particle accelerator control expert system (PACES) is a computer-based operator aid, retrofitted to a model KN-3000 Van de Graaff accelerator, that is used during the start-up, steady state and shut-down phases of the accelerator. Using PACES, the operator can control the accelerator through a graphical control panel, or call upon an expert system to perform automatic start-up or shut-down. PACES then automatically stabilizes and optimizes particle beam parameters. PACES is also able to detect, diagnose and respond to operating faults, such as high-voltage sparks, vacuum system failure or loss of source gas. This paper demonstrates the novel features and utility of the PACES artificial intelligence accelerator controller

  20. How do we perceive activity pacing in rheumatology care?

    DEFF Research Database (Denmark)

    Cuperus, N.; Vliet Vlieland, T.; Brodin, N.;

    2015-01-01

    -pharmacological rheumatology care. Methods: An international, multidisciplinary expert panel comprising 60 clinicians and/or healthcare providers experienced with activity pacing across 12 different countries participated in a Delphi survey. Over four Delphi rounds, the panellists identified and ranked the most important......-management programs. However, despite its wide endorsement in clinical practice, to date activity pacing is still a poorly understood concept. Objectives: To achieve consensus by means of an international Delphi exercise on the most important aspects of activity pacing as an intervention within non...... future research on activity pacing were formulated and prioritized. Results: Of the 60 panelists, nearly two third (63%) completed all four Delphi rounds. The panel prioritized 9 goals, 11 behaviours, 9 strategies to change behaviour and 10 contextual factors of activity pacing. These items were...

  1. A comparison of single-lead atrial pacing with dual-chamber pacing in sick sinus syndrome

    DEFF Research Database (Denmark)

    Nielsen, Jens Cosedis; Thomsen, Poul Erik B; Højberg, Søren;

    2011-01-01

    In patients with sick sinus syndrome, bradycardia can be treated with a single-lead pacemaker or a dual-chamber pacemaker. Previous trials have revealed that pacing modes preserving atrio-ventricular synchrony are superior to single-lead ventricular pacing, but it remains unclear if there is any ...

  2. Pushing the pace of tree species migration.

    Directory of Open Access Journals (Sweden)

    Eli D Lazarus

    Full Text Available Plants and animals have responded to past climate changes by migrating with habitable environments, sometimes shifting the boundaries of their geographic ranges by tens of kilometers per year or more. Species migrating in response to present climate conditions, however, must contend with landscapes fragmented by anthropogenic disturbance. We consider this problem in the context of wind-dispersed tree species. Mechanisms of long-distance seed dispersal make these species capable of rapid migration rates. Models of species-front migration suggest that even tree species with the capacity for long-distance dispersal will be unable to keep pace with future spatial changes in temperature gradients, exclusive of habitat fragmentation effects. Here we present a numerical model that captures the salient dynamics of migration by long-distance dispersal for a generic tree species. We then use the model to explore the possible effects of assisted colonization within a fragmented landscape under a simulated tree-planting scheme. Our results suggest that an assisted-colonization program could accelerate species-front migration rates enough to match the speed of climate change, but such a program would involve an environmental-sustainability intervention at a massive scale.

  3. Deterioration of left ventricular function following atrio-ventricular node ablation and right ventricular apical pacing in patients with permanent atrial fibrillation

    OpenAIRE

    Szili-Torok, Tamas; Kimman, Geert-Jan; Poldermans, Don; Jordaens, Luc; Roelandt, Jos; Theuns, Dominic

    2002-01-01

    textabstractAIMS: Transcatheter radiofrequency ablation of the atrio-ventricular (AV) node followed by ventricular pacing has been shown to improve symptoms and quality of life of patients with atrial fibrillation (AF). It is assumed that function improves, but this has been less well demonstrated. The aim of this study was to assess the long-term effect of AV node ablation and ventricular pacing on left ventricular ejection fraction (LVEF) in patients with permanent AF. METHODS AND RESULTS: ...

  4. Remote Sensing Ocean Color Observations from NASA's PACE Mission: Applications and Societal Benefits

    Science.gov (United States)

    Tzortziou, M.; Omar, A. H.; Turner, W.

    2014-12-01

    The PACE (Pre- Aerosol, Clouds and ocean Ecosystems) mission is a strategic Climate Continuity mission, included in NASA's 2010 plan: "Responding to the Challenge of Climate and Environmental Change: NASA's Plan for a Climate-Centric Architecture for Earth Observations and Applications from Space". On a polar orbit, PACE will make climate-quality global measurements that are essential for understanding ocean biology, biogeochemistry and ecology, and determining how the ocean's role in global biogeochemical cycling and ocean ecology both affects and is affected by climate change. With advanced global remote sensing capabilities that include high spectral-resolution imaging, extended spectral coverage to the UV and SWIR, improved spatial resolution in inland, estuarine and coastal waters, enhanced atmospheric correction and higher signal-to-noise, PACE is expected to provide high quality observations that, over the long-term, will contribute to an extended time series of records on inland, coastal, and ocean ecosystems—all of which have substantial value beyond basic science and research. The combination of climate-quality, global atmospheric and oceanic observations provided by the PACE mission will provide a unique capability to help understand changes that affect our ecosystem services, implement science-based management strategies of coastal, marine and inland aquatic resources, and support assessments, policy analyses, and design approaches to plan adaptation and responses to impacts of climate change. Here we discuss the PACE applications program, the new capabilities afforded by this future satellite mission, and how they could potentially advance applications across a range of areas, including Oceans, Climate, Water Resources, Ecological Forecasting, Disasters, Human Health and Air Quality.

  5. Development of Pacing, Electrophysiology and Defibrillation in India

    OpenAIRE

    Nair, Mohan; Francis, Johnson; Venugopal, K

    2002-01-01

    History of cardiac pacing in India dates back to late 1960s. Kar1 reported that cardiac pacing was introduced in India in 1966. Basu2 while discussing on cardiac pacemaking in Calcutta, mentions that the first pacing was performed in April 1967 at the Institute of Post Graduate Medical Education and Research (IPGME&R). Bhatia et al3 started pacemaker implantation at AIIMS, New Delhi in 1968. Their first patient was a doctor from Assam and the pulse generator was supplied by Medtronic Inc. Th...

  6. A bi-ventricular cardiac atlas built from 1000+ high resolution MR images of healthy subjects and an analysis of shape and motion.

    Science.gov (United States)

    Bai, Wenjia; Shi, Wenzhe; de Marvao, Antonio; Dawes, Timothy J W; O'Regan, Declan P; Cook, Stuart A; Rueckert, Daniel

    2015-12-01

    Atlases encode valuable anatomical and functional information from a population. In this work, a bi-ventricular cardiac atlas was built from a unique data set, which consists of high resolution cardiac MR images of 1000+ normal subjects. Based on the atlas, statistical methods were used to study the variation of cardiac shapes and the distribution of cardiac motion across the spatio-temporal domain. We have shown how statistical parametric mapping (SPM) can be combined with a general linear model to study the impact of gender and age on regional myocardial wall thickness. Finally, we have also investigated the influence of the population size on atlas construction and atlas-based analysis. The high resolution atlas, the statistical models and the SPM method will benefit more studies on cardiac anatomy and function analysis in the future. PMID:26387054

  7. Determination of myocardial energetic output for cardiac rhythm pacing

    OpenAIRE

    Heřman, Dalibor; Převorovská, Světlana; Maršík, František

    2007-01-01

    This research is aimed to the determination of the changes in the cardiac energetic output for three different modes of cardiac rhythm pacing. The clinical investigation of thirteen patients with the permanent dual-chamber pacemaker implantation was carried out. The patients were taken to echocardiography examination conducted by way of three pacing modes (AAI, VVI and DDD). The myocardial energetic parameters—the stroke work index (SWI) and the myocardial oxygen consumption (MVO2) are not di...

  8. Factors explaining voluntary participation in PACE-Vaquita

    OpenAIRE

    Sara Avila

    2011-01-01

    Vaquita marina, a small species of porpoise endemic to the Northern Gulf of California in Mexico, is the world’s most endangered cetacean species. With the purpose of preserving vaquita, the Mexican government launched PACE-Vaquita in 2008. This voluntary program offers an innovative schedule of compensations: as in a payment for conservation program, PACE-Vaquita compensates for temporary reductions in fishing reductions in fishing effort; as in a program to accelerate technology adoption,PA...

  9. PACE and the Federal Housing Finance Agency (FHFA)

    Energy Technology Data Exchange (ETDEWEB)

    Zimring, Mark; Fuller, Merrian

    2010-03-17

    The FHFA regulates Fannie Mae, Freddie Mac, and the 12 Federal Home Loan Banks (the government-sponsored enterprises - GSEs). On June 18, 2009, James B. Lockhart III, then Director of FHFA, released a letter expressing concern about the negative impact of energy loan tax assessment programs (ELTAPs) - also known as Property Assessed Clean Energy (PACE) programs - on both the housing finance system and homeowner program participants. Subsequently, a number of PACE proponents responded to the concerns laid out in the FHFA letter. In early Fall 2009, word circulated that FHFA was planning to follow its June letter with guidance to other agencies, possibly including Fannie Mae and Freddie Mac, discouraging them from buying loans on properties subject to PACE-type assessment liens. This triggered a second round of stakeholder letters, several of which were addressed to President Obama. On October 18, 2009, the White House, in what some believe was an attempt to obviate the need for FHFA guidance, released a Policy Framework for PACE Financing Programs that outlined best practices guidance for homeowner and lender protection. As of February 2010, FHFA and the GSEs have agreed to monitor PACE programs and work with stakeholders and the Administration to consider additional guidance beyond the Policy Framework and to collect more information on PACE program efficacy and risks. A summary of the communications timeline and highlights of the communications are provided.

  10. The Pace of Perceivable Extreme Climate Change

    Science.gov (United States)

    Tan, X.; Gan, T. Y.

    2015-12-01

    When will the signal of obvious changes in extreme climate emerge over climate variability (Time of Emergence, ToE) is a key question for planning and implementing measures to mitigate the potential impact of climate change to natural and human systems that are generally adapted to potential changes from current variability. We estimated ToEs for the magnitude, duration and frequency of global extreme climate represented by 24 extreme climate indices (16 for temperature and 8 for precipitation) with different thresholds of the signal-to-noise (S/N) ratio based on projections of CMIP5 global climate models under RCP8.5 and RCP4.5 for the 21st century. The uncertainty of ToE is assessed by using 3 different methods to calculate S/N for each extreme index. Results show that ToEs of the projected extreme climate indices based on the RCP4.5 climate scenarios are generally projected to happen about 20 years later than that for the RCP8.5 climate scenarios. Under RCP8.5, the projected magnitude, duration and frequency of extreme temperature on Earth will all exceed 2 standard deviations by 2100, and the empirical 50th percentile of the global ToE for the frequency and magnitude of hot (cold) extreme are about 2040 and 2054 (2064 and 2054) for S/N > 2, respectively. The 50th percentile of global ToE for the intensity of extreme precipitation is about 2030 and 2058 for S/N >0.5 and S/N >1, respectively. We further evaluated the exposure of ecosystems and human societies to the pace of extreme climate change by determining the year of ToE for various extreme climate indices projected to occur over terrestrial biomes, marine realms and major urban areas with large populations. This was done by overlaying terrestrial, ecoregions and population maps with maps of ToE derived, to extract ToEs for these regions. Possible relationships between GDP per person and ToE are also investigated by relating the mean ToE for each country and its average value of GDP per person.

  11. Towards Development of a 3-State Self-Paced Brain-Computer Interface

    Directory of Open Access Journals (Sweden)

    Ali Bashashati

    2007-01-01

    the presence of a right- or a left-hand movement and the second classifies the detected movement as a right or a left one. In an offline analysis of the EEG data collected from four able-bodied individuals, the 3-state brain-computer interface shows a comparable performance with a 2-state system and significant performance improvement if used as a 2-state BCI, that is, in detecting the presence of a right- or a left-hand movement (regardless of the type of movement. It has an average true positive rate of 37.5% and 42.8% (at false positives rate of 1% in detecting right- and left-hand extensions, respectively, in the context of a 3-state self-paced BCI and average detection rate of 58.1% (at false positive rate of 1% in the context of a 2-state self-paced BCI.

  12. Spontaneous Velocity Effect of Musical Expression on Self-Paced Walking.

    Science.gov (United States)

    Buhmann, Jeska; Desmet, Frank; Moens, Bart; Van Dyck, Edith; Leman, Marc

    2016-01-01

    The expressive features of music can influence the velocity of walking. So far, studies used instructed (and intended) synchronization. But is this velocity effect still present with non-instructed (spontaneous) synchronization? To figure that out, participants were instructed to walk in their own comfort tempo on an indoor track, first in silence and then with tempo-matched music. We compared velocities of silence and music conditions. The results show that some music has an activating influence, increasing velocity and motivation, while other music has a relaxing influence, decreasing velocity and motivation. The influence of musical expression on the velocity of self-paced walking can be predicted with a regression model using only three sonic features explaining 56% of the variance. Phase-coherence between footfall and beat did not contribute to the velocity effect, due to its implied fixed pacing. The findings suggest that the velocity effect depends on vigor entrainment that influences both stride length and pacing. Our findings are relevant for preventing injuries, for gait improvement in walking rehabilitation, and for improving performance in sports activities. PMID:27167064

  13. Spontaneous Velocity Effect of Musical Expression on Self-Paced Walking.

    Directory of Open Access Journals (Sweden)

    Jeska Buhmann

    Full Text Available The expressive features of music can influence the velocity of walking. So far, studies used instructed (and intended synchronization. But is this velocity effect still present with non-instructed (spontaneous synchronization? To figure that out, participants were instructed to walk in their own comfort tempo on an indoor track, first in silence and then with tempo-matched music. We compared velocities of silence and music conditions. The results show that some music has an activating influence, increasing velocity and motivation, while other music has a relaxing influence, decreasing velocity and motivation. The influence of musical expression on the velocity of self-paced walking can be predicted with a regression model using only three sonic features explaining 56% of the variance. Phase-coherence between footfall and beat did not contribute to the velocity effect, due to its implied fixed pacing. The findings suggest that the velocity effect depends on vigor entrainment that influences both stride length and pacing. Our findings are relevant for preventing injuries, for gait improvement in walking rehabilitation, and for improving performance in sports activities.

  14. Spontaneous Velocity Effect of Musical Expression on Self-Paced Walking

    Science.gov (United States)

    Buhmann, Jeska; Desmet, Frank; Moens, Bart; Van Dyck, Edith; Leman, Marc

    2016-01-01

    The expressive features of music can influence the velocity of walking. So far, studies used instructed (and intended) synchronization. But is this velocity effect still present with non-instructed (spontaneous) synchronization? To figure that out, participants were instructed to walk in their own comfort tempo on an indoor track, first in silence and then with tempo-matched music. We compared velocities of silence and music conditions. The results show that some music has an activating influence, increasing velocity and motivation, while other music has a relaxing influence, decreasing velocity and motivation. The influence of musical expression on the velocity of self-paced walking can be predicted with a regression model using only three sonic features explaining 56% of the variance. Phase-coherence between footfall and beat did not contribute to the velocity effect, due to its implied fixed pacing. The findings suggest that the velocity effect depends on vigor entrainment that influences both stride length and pacing. Our findings are relevant for preventing injuries, for gait improvement in walking rehabilitation, and for improving performance in sports activities. PMID:27167064

  15. Biomechanically and electromyographically assessed load on the spine in self-paced and force-paced lifting work.

    Science.gov (United States)

    Leskinen, T P; Stålhammar, H R; Rautanen, M T; Troup, J D

    1992-01-01

    The purpose of this study was to measure dose of spinal load when different pacing methods were applied to lifting work and to develop methodology for such measurements. The compressive load on the spine computed by a dynamic biomechanical model and the electromyographic activity of back muscles were used for describing the spinal load. Five men and five women worked in a laboratory on two days lifting a box up and down for 30 min on both days, on one day force-paced (4 lifts/min), and on the other self-paced in random order. The weight of the box was rated by the subjects to be acceptable for the work done. The lift rate of our female subjects was higher and that of the male subjects lower in self-paced than in force-paced work. There were no significant differences in peak lumbosacral compressions nor in the amplitude distributions of electromyography between the two pacing methods. The biomechanically-calculated compressive forces on the spine were lower (about 2.7 kN for the men and 2.3 kN for women) than the biomechanical recommendations for safe lifting, but the EMG activity showed quite high peaks so that for 1% of work time the activity was on women above 60% and on men above 40% of the activity during maximum isometric voluntary test contraction. PMID:1633794

  16. The effects of fluid ingestion on free-paced intermittent-sprint performance and pacing strategies in the heat.

    Science.gov (United States)

    Skein, Melissa; Duffield, Rob

    2010-02-01

    The purpose of this study was to examine the effects of fluid ingestion on pacing strategies and performance during intermittent-sprint exercise in the heat. Nine male rugby players performed a habituation session and 2 x 50-min intermittent-sprint protocols at a temperature of 31 degrees C, either with or without fluid. Participants were informed of a third session (not performed) to ensure that they remained blind to all respective conditions. The protocol consisted of a 15-m sprint every minute separated by self-paced bouts of hard running, jogging, and walking for the remainder of the minute. Sprint time, distance covered during self-paced exercise, and vertical jump height before and after exercise were recorded. Heart rate, core temperature, nude mass, capillary blood haematocrit, pH, lactate concentration, perceptual ratings of perceived exertion, thermal stress, and thirst were also recorded. Sprint times (fluid vs. no-fluid: 2.82 +/- 0.11 vs. 2.82 +/- 0.14) and distance covered during self-paced exercise (fluid vs. no-fluid: 4168 +/- 419 vs. 3981 +/- 263 m) were not different between conditions (P = 0.10-0.98) but were progressively reduced to a greater extent in the no-fluid trial (7 +/- 13%) (d = 0.56-0.58). There were no differences (P = 0.22-1.00; d = affect pacing strategies with a greater reduction in distance covered of self-paced exercise during the no-fluid trial. PMID:20077276

  17. Comparison of longevity, paging, and sensing characteristics of steroid-eluting epicardial versus conventional endocardial pacing leads in children

    NARCIS (Netherlands)

    Beaufort-Krol, GCM; Mulder, H; Nagelkerke, D; Waterbolk, TW; Bink-Boelkens, MTE

    1999-01-01

    Objective: Because of either cardiac anatomy or small size, pacing in children often occurs by means of epicardial leads. The disadvantage of epicardial leads is the shorter longevity of these leads compared with endocardial leads. During short-term follow-up, improved stimulation thresholds were fo

  18. Ross-Konno and Endocardial Fibroelastosis Resection After Hybrid Stage I Palliation in Infancy: Successful Staged Left-Ventricular Rehabilitation and Conversion to Biventricular Circulation After Fetal Diagnosis of Aortic Stenosis

    OpenAIRE

    Moon-Grady, Anita J.; Moore, Phillip; Azakie, Anthony

    2010-01-01

    We report a patient who presented during fetal life with severe aortic stenosis, left-ventricular dysfunction, and endocardial fibroelastosis (evolving hypoplastic left heart syndrome). Management involved in utero and postnatal balloon aortic valvuloplasty for partial relief of obstruction and early postnatal hybrid stage I palliation until recovery of left-ventricular systolic function had occurred. The infant subsequently had successful conversion to a biventricular circulation by combinin...

  19. The distribution of pace adopted by cyclists during a cross-country mountain bike World Championships.

    Science.gov (United States)

    Abbiss, Chris R; Ross, Megan L R; Garvican, Laura A; Ross, Neil; Pottgiesser, Torben; Gregory, John; Martin, David T

    2013-01-01

    The purpose of this study was to examine the distribution of pace self-selected by cyclists of varying ability, biological age and sex performing in a mountain bike World Championship event. Data were collected on cyclists performing in the Elite Male (ELITEmale; n = 75), Elite Female (ELITEfemale; n = 50), Under 23 Male (U23male; n = 62), Under 23 Female (U23female; n = 34), Junior Male (JNRmale; n = 71) and Junior Female (JNRfemale; n = 30) categories of the 2009 UCI Cross-Country Mountain Bike World Championships. Split times were recorded for the top, middle and bottom 20% of all finishers of each category. Timing splits were positioned to separate the course into technical and non-technical, uphill, downhill and rolling/flat sections. Compared with bottom performers, top performers in all male categories (ELITEmale, U23male, JNRmale) maintained a more even pace over the event as evidenced by a significantly lower standard deviation and range in average lap speed. Top performers, males, and ELITEmale athletes spent a lower percentage of overall race time on technical uphill sections of the course, compared with middle and bottom placed finishers, females, and JNRmale athletes, respectively. Better male performers adopt a more even distribution of pace throughout cross-country mountain events. Performance of lower placed finishers, females and JNRmale athletes may be improved by enhancing technical uphill cycling ability. PMID:23521618

  20. Pacing accuracy during an incremental step test in adolescent swimmers

    Directory of Open Access Journals (Sweden)

    Scruton A

    2015-08-01

    Full Text Available Adrian Scruton, James Baker, Justin Roberts, Itay Basevitch, Viviane Merzbach, Dan Gordon Sport and Exercise Sciences Research Group, Anglia Ruskin University, Cambridge, UK Abstract: To assess pacing accuracy in a group of adolescent swimmers during an incremental step test. Fifteen well-trained swimmers (age 15±1.5 years; height 170.2±8.8 cm; mass 60.2±6.6 kg, completed two 7×200 m tests, separated by ~72 hours. They swam to a predetermined incrementally increasing pace per step and were instructed to swim at even pace. Upon completion of each step, rating of perceived exertion, heart rate and blood lactate were recorded. Significant differences observed for both trials between actual and predicted swim time (P<0.05. Significant differences also observed between the first and second 100 m of each step in trial 1 for step 1 (P=0.001, effect size [ES] =0.54, step 2 (P=0.0001, ES =0.57, step 4 (P=0.0001, ES =0.53, step 5 (P=0.005, ES =0.65, step 6 (P=0.0001, ES =0.50, and step 7 (P=0.0001, ES =0.70. Similar responses witnessed for trial 2 (P<0.05. Findings suggest that the finite anaerobic capacity was engaged sooner than would normally be anticipated, as a function of an inability to regulate pace. This is proposed to be a consequence of the volume of exposure to the biological and psychological sensations and cognitive developmental status. Given the apparent error in pacing judgment exhibited in this population group, caution should be applied when adopting such tests to monitor training responses with adolescent athletes, and alternate means of modulating pace be investigated. Keywords: effort regulation, children, exercise testing, perception

  1. Social Interaction in Self-paced Distance Education

    OpenAIRE

    Terry Anderson; Lorne Upton; Jon Dron; Judi Malone; Bruno Poelhuber

    2015-01-01

    In this paper we present a case study of a self-paced university course that was originally designed to support independent, self-paced study at distance. We developed a social media intervention, in design-based research terms, that allows these independent students to contribute archived content to enhance the course, to engage in discussions with other students and to share as little or as much personal information with each other as they wished. We describe the learning design for the int...

  2. EFFECTS OF MUSIC ON PERCEPTUAL RESPONSES AND PACING STRATEGY

    OpenAIRE

    Flávio de Oliveira Pires; Rômulo Cássio de Moraes Bertuzzi; Adriano Eduardo Lima-Silva; Agedani Pacheco Correia do Rozario; Ana Gabriela de M. Simões; João Paulo Lopes da Silva; Marcos David da Silva-Cavalcante; Thomaz Roberto Carvalho Carnaúba; Fernando Roberto de-Oliveira

    2011-01-01

    CARNAÚBA, T. R. C.; SILVA-CAVALCANTE, M. D.; SILVA, J. P. L.; SIMÕES, A. G. M.; 1, ROZARIO, A. P. C.; BERTUZZI, R. C. M.; PIRES, F. O.; DE-OLIVEIRA, F. R.; LIMA-SILVA, A. E. Effects of music on perceptual responses and pacing strategy. Brazilian Journal of Biomotricity. v. 5, n. 3, p. 210-220, 2011. The purpose of this study was verify the effects of music on perceptual responses and pacing strategy during 5-km running. Fifteen men (22.5 ± 3.5 years; 177.7 ± 6 cm; 76.0 ± 7.0 kg) they accom...

  3. International piping benchmarks: Use of simplified code PACE 2

    International Nuclear Information System (INIS)

    This report compares the results obtained using the code PACE 2 with the International Working Group on Fast Reactors (IWGFR) International Piping Benchmark solutions. PACE 2 is designed to analyse systems of pipework using a simplified method which is economical of computer time and hence inexpensive. This low cost is not achieved without some loss of accuracy in the solution, but for most parts of a system this inaccuracy is acceptable and those sections of particular importance may be reanalysed using more precise methods in order to produce a satisfactory analysis of the complete system at reasonable cost. (author)

  4. DiPALS: Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis - a randomised controlled trial.

    Science.gov (United States)

    McDermott, Christopher J; Bradburn, Mike J; Maguire, Chin; Cooper, Cindy L; Baird, Wendy O; Baxter, Susan K; Cohen, Judith; Cantrill, Hannah; Dixon, Simon; Ackroyd, Roger; Baudouin, Simon; Bentley, Andrew; Berrisford, Richard; Bianchi, Stephen; Bourke, Stephen C; Darlison, Roy; Ealing, John; Elliott, Mark; Fitzgerald, Patrick; Galloway, Simon; Hamdalla, Hisham; Hanemann, C Oliver; Hughes, Philip; Imam, Ibrahim; Karat, Dayalan; Leek, Roger; Maynard, Nick; Orrell, Richard W; Sarela, Abeezar; Stradling, John; Talbot, Kevin; Taylor, Lyn; Turner, Martin; Simonds, Anita K; Williams, Tim; Wedzicha, Wisia; Young, Carolyn; Shaw, Pamela J

    2016-01-01

    BACKGROUND Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting in death, usually from respiratory failure, within 2-3 years of symptom onset. Non-invasive ventilation (NIV) is a treatment that when given to patients in respiratory failure leads to improved survival and quality of life. Diaphragm pacing (DP), using the NeuRx/4(®) diaphragm pacing system (DPS)™ (Synapse Biomedical, Oberlin, OH, USA), is a new technique that may offer additional or alternative benefits to patients with ALS who are in respiratory failure. OBJECTIVE The Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis (DiPALS) trial evaluated the effect of DP on survival over the study duration in patients with ALS with respiratory failure. DESIGN The DiPALS trial was a multicentre, parallel-group, open-label, randomised controlled trial incorporating health economic analyses and a qualitative longitudinal substudy. PARTICIPANTS Eligible participants had a diagnosis of ALS (ALS laboratory-supported probable, clinically probable or clinically definite according to the World Federation of Neurology revised El Escorial criteria), had been stabilised on riluzole for 30 days, were aged ≥ 18 years and were in respiratory failure. We planned to recruit 108 patients from seven UK-based specialist ALS or respiratory centres. Allocation was performed using 1 : 1 non-deterministic minimisation. INTERVENTIONS Participants were randomised to either standard care (NIV alone) or standard care (NIV) plus DP using the NeuRX/4 DPS. MAIN OUTCOME MEASURES The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Secondary outcomes were patient quality of life [assessed by European Quality of Life-5 Dimensions, three levels (EQ-5D-3L), Short Form questionnaire-36 items and Sleep Apnoea Quality of Life Index questionnaire]; carer quality of life (EQ-5D-3L and Caregiver Burden Inventory); cost-utility analysis and health

  5. Investigating possible ethnicity and sex bias in clinical examiners: an analysis of data from the MRCP(UK) PACES and nPACES examinations

    OpenAIRE

    McManus, I C; Elder, A T; DACRE, J

    2013-01-01

    Background Bias of clinical examiners against some types of candidate, based on characteristics such as sex or ethnicity, would represent a threat to the validity of an examination, since sex or ethnicity are ‘construct-irrelevant’ characteristics. In this paper we report a novel method for assessing sex and ethnic bias in over 2000 examiners who had taken part in the PACES and nPACES (new PACES) examinations of the MRCP(UK). Method PACES and nPACES are clinical skills examinations that have ...

  6. Self-Paced Physics, Segments 24-27.

    Science.gov (United States)

    New York Inst. of Tech., Old Westbury.

    Four study segments of the Self-Paced Physics Course materials are presented in this fifth problems and solutions book used as a part of student course work. The subject matter is related to work in electric fields, potential differences, parallel plates, electric potential energies, potential gradients, capacitances, and capacitor circuits.…

  7. Determination of myocardial energetic output for cardiac rhythm pacing

    Czech Academy of Sciences Publication Activity Database

    Heřman, D.; Převorovská, Světlana; Maršík, František

    2007-01-01

    Roč. 7, č. 4 (2007), s. 156-161. ISSN 1567-8822 R&D Projects: GA ČR GA106/03/1073 Institutional research plan: CEZ:AV0Z20760514 Keywords : heart arrhythmia * cardiac pacing modes * numerical simulation Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  8. Self-paced training for quality control inspectors

    International Nuclear Information System (INIS)

    The authors discuss the need for quality control (QC) training in the nuclear industry and propose requirements for QC training. This paper presents an overview of a self-paced training program for QC, including the characteristics and structure of such a program

  9. The pace of shifting climate in marine and terrestrial ecosystems

    DEFF Research Database (Denmark)

    Burrows, Michael T.; Schoeman, David S.; Buckley, Lauren B.;

    2011-01-01

    Climate change challenges organisms to adapt or move to track changes in environments in space and time. We used two measures of thermal shifts from analyses of global temperatures over the past 50 years to describe the pace of climate change that species should track: the velocity of climate cha...

  10. Hardware packet pacing using a DMA in a parallel computer

    Science.gov (United States)

    Chen, Dong; Heidelberger, Phillip; Vranas, Pavlos

    2013-08-13

    Method and system for hardware packet pacing using a direct memory access controller in a parallel computer which, in one aspect, keeps track of a total number of bytes put on the network as a result of a remote get operation, using a hardware token counter.

  11. "Set the Pace": Nutrition Education DVD for Head Start Parents

    Science.gov (United States)

    Adedze, Pascasie; Orr, Robin A.; Chapman-Novakofski, Karen; Donovan, Sharon M.

    2013-01-01

    Childhood overweight remains a major public health problem and innovative nutrition education programs are still needed. Thus, the "Set the Pace" is a nutrition education DVD for Head Start parents which provides visual nutrition education and physical activities to incorporate in their daily routines. (Contains 1 table.)

  12. Self-Paced Physics, Segments 28-31.

    Science.gov (United States)

    New York Inst. of Tech., Old Westbury.

    Four study segments of the Self-Paced Physics Course materials are presented in this sixth problems and solutions book used as a part of student course work. The subject matter is related to electric currents, current densities, resistances, Ohm's law, voltages, Joule heating, electromotive forces, single loop circuits, series and parallel…

  13. MFTF-B PACE tests and final cost report

    International Nuclear Information System (INIS)

    The Mirror Fusion Test Facility (MFTF-B) construction project was successfully completed in February 1986, with the conclusion of the Plant and Capital Equipment (PACE) Tests. This series of tests, starting in September 1985 and running through February 1986, demonstrated the overall machine capabilities and special facilities accomplishments for the Mirror Fusion Test Facility Project

  14. What Pace Is Best? Assessing Adults' Learning from Slideshows and Video

    Science.gov (United States)

    Sage, Kara

    2014-01-01

    When acquiring information from a 2D platform, self-control and/or optimal pacing may help reduce cognitive load and enhance learning outcomes. In the present research, adults viewed novel action sequences via one of four learning media: (1) self-paced slideshows, where viewers advanced through slides at their own pace by clicking a mouse, (2)…

  15. Society for the Teaching of Psychology and the University of Wisconsin-Milwaukee: U-Pace

    Science.gov (United States)

    EDUCAUSE, 2014

    2014-01-01

    The Society for the Teaching of Psychology and the University of Wisconsin-Milwaukee (UWM) partnered to disseminate U-Pace, a technology-enabled instructional model that promotes student success through deeper learning. UWM developed U-Pace in 2006 for an Introduction to Psychology course and, over time, evidence indicates that U-Pace not only…

  16. Left ventricular vs. biventricular mechanical support: Decision making and strategies for avoidance of right heart failure after left ventricular assist device implantation.

    Science.gov (United States)

    Dandel, Michael; Krabatsch, Thomas; Falk, Volkmar

    2015-11-01

    Left ventricular assist devices (LVADs) are safer and provide better survival and better quality of life than biventricular assist devices (BVADs) but end-stage heart failure often involves both ventricles, even if its initial cause was left-sided heart disease. Right ventricular failure (RVF) is also a severe complication in about 25% of patients receiving an LVAD, with high perioperative morbidity (renal, hepatic or multi-organ failure) and mortality. Patients who receive an RV assist device (RVAD) only days after LVAD insertion fare much worse than those who receive an RVAD simultaneously with LVAD implantation. Temporary RVAD support in LVAD recipients with high risk for postoperative RVF can avoid permanent BVAD support. Thus, patients who definitely need a BVAD should already be identified preoperatively or at least intra-operatively. However, although the initial biochemical, hemodynamic and echocardiographic patient profiles at admission may suggest the need for a BVAD, many risk factors may be favorably modified by various strategies that may result in avoidance of RVF after LVAD implantation. This article summarizes the knowledge of risk factors for irreversible RVF after LVAD implantation and strategies to optimize RV function (preoperatively, intra-operatively and post-operatively) aimed to reduce the number of BVAD implantations. Special attention is focused on assessment of RV size, geometry and function in relation to loading conditions with the goal of predicting preoperatively the RV changes which might be induced by RV afterload reduction with the LVAD. The review also provides a theoretical and practical basis for clinicians intending to be engaged in this field. PMID:26232775

  17. Prevention of Atrioventricular Block During Radiofrequency Ablation by Pace Mapping of Koch’s Triangle

    Directory of Open Access Journals (Sweden)

    Hossein Vakili

    2008-08-01

    Full Text Available Background: Complete atrioventricular block (AV block is a serious complication of slow pathway ablation therapy in the treatment of atrioventricular nodal re-entrant tachycardia (AVNRT. The present study was aimed at determining whether the electroanatomical pace mapping of Koch’s triangle could significantly improve the safety, efficiency, and efficacy of selective slow pathway ablation in the treatment of AVNRT. Methods: A total number of 124 patients were selected to be studied consecutively for radiofrequency (RF ablation therapy in the treatment of AVNRT. The subjects were divided into two groups: one, designated Group 1, to serve as the control group, and the other, designated Group 2, to serve as the study group. Conventional fluoroscopic slow pathway ablation was performed on the Group 1 subjects (n=66, with the Group 2 subjects receiving slow pathway ablation therapy guided by pace mapping of Koch’s triangle. The slow pathway ablation in Group 2 (n=58 was performed with regard to the pace mapping data obtained on the basis of the St-H interval in the anteroseptal (AS, midseptal (MS, and posteroseptal (PS regions of Koch’s triangle. The anterograde fast pathway (AFP location was determined based on the shortest St-H interval obtained by stimulating the anteroseptal (AS, midseptal (MS, and posteroseptal (PS aspects of Koch’s triangle. Results: In the Group 2 subjects, AFP location was AS in 50 (86.2% of the cases, MS in 7 (12% of the cases, and PS in 1 case (1.7%. One patient with posteroseptal AFP was administered retrograde fast pathway ablation therapy. One patient in the control group (Group 1, representing 1.5% of the group, developed persistent AV block in the course of the treatment, but none of the subjects in the study group (Group 2 developed any complications. Conclusion: It was concluded that an atypical fast pathway location is conducive to the development of atrioventricular block in the ablation therapy in AVNRT

  18. Optimal pacing strategy for a race of two competing cyclists

    OpenAIRE

    Dahmen, Thorsten; Saupe, Dietmar

    2014-01-01

    For optimal pacing strategies in the case of two or more competing or cooperating cyclists only few approaches take slipstreaming into account. However, by incorporating the slipstream effect in the model of a race of two runners on a flat course , it has been shown, how the trailing runner can position himself at striking distance behind the other and when he should start the final sprint. (Pitcher, 2009: Optimal strategies for a two - runner model of middle - distance running. SIAM Journal ...

  19. Programming the programme: pacing the curriculum in architectural education

    OpenAIRE

    Holgate, Peter; Roberts, Stephen

    2012-01-01

    Constructive alignment in project based learning provides the opportunity to ‘entrap students in a web of consistency’ (Biggs, 1999). While the central design of a curriculum can incorporate the core elements of a syllabus for successful alignment, consideration of pace and timing of content delivery, assessment and learning opportunities can enhance student engagement and satisfaction. This paper draws upon a case study of the second year architecture curriculum at Northumbria University....

  20. Recognition of ventricular fibrillation concomitant with pacing artifacts

    OpenAIRE

    Zysko, Dorota; Smereka, Jacek; CHÊCIÑSKI, IGOR; WRÓBLEWSKI, PAWE£; TERPI£OWSKI, £UKASZ; JACEK, GAJEK; WALDEMAR, GOZDZIK; KUMAR AGRAWAL, ANIL

    2013-01-01

    Introduction. In pre-hospital settings recognition of underlying rhythm in patients with ventricular stimulation can be difficult especially when a 3-lead electrocardiogram (ECG) is analyzed. This fact is particularly important in patients with life-threatening cardiac dysrhythmias. The pacing spikes in the ECG of a patient with cardiac arrest due to ventricular fibrillation may be misdiagnosed as QRS complexes. Aim of the study. The aim of this study was to assess emergency medical care stud...

  1. A Combination of Pre- and Postprocessing Techniques to Enhance Self-Paced BCIs

    Directory of Open Access Journals (Sweden)

    Raheleh Mohammadi

    2012-01-01

    Full Text Available Mental task onset detection from the continuous electroencephalogram (EEG in real time is a critical issue in self-paced brain computer interface (BCI design. The paper shows that self-paced BCI performance can be significantly improved by combining a range of simple techniques including (1 constant-Q filters with varying bandwidth size depending on the center frequency, instead of constant bandwidth filters for frequency decomposition of the EEG signal in the 6 to 36 Hz band; (2 subject-specific postprocessing parameter optimization consisting of dwell time and threshold, and (3 debiasing before postprocessing by readjusting the classification output based on the current and previous brain states, to reduce the number of false detections. This debiasing block is shown to be optimal when activated only in special cases which are predetermined during the training phase. Analysis of the data recorded from seven subjects executing foot movement shows a statistically significant 10% ( average improvement in true positive rate (TPR and a 1% reduction in false positive rate (FPR detections compared with previous work on the same data.

  2. Determination of myocardial energetic output for cardiac rhythm pacing.

    Science.gov (United States)

    Herman, Dalibor; Prevorovská, Svetlana; Marsík, Frantisek

    2007-12-01

    This research is aimed to the determination of the changes in the cardiac energetic output for three different modes of cardiac rhythm pacing. The clinical investigation of thirteen patients with the permanent dual-chamber pacemaker implantation was carried out. The patients were taken to echocardiography examination conducted by way of three pacing modes (AAI, VVI and DDD). The myocardial energetic parameters-the stroke work index (SWI) and the myocardial oxygen consumption (MVO2) are not directly measurable, however, their values can be determined using the numerical model of the human cardiovascular system. The 24-segment hemodynamical model (pulsating type) of the human cardiovascular system was used for the numerical simulation of the changes of myocardial workload for cardiac rhythm pacing. The model was fitted by well-measurable parameters for each patient. The calculated parameters were compared using the two-tailed Student's test. The differences of SWI and MVO2 between the modes AAI and VVI and the modes DDD and VVI are statistically significant (P0.05). PMID:18080208

  3. MRI with cardiac pacing devices – Safety in clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Kaasalainen, Touko, E-mail: touko.kaasalainen@hus.fi [HUS Medical Imaging Center, Helsinki University Central Hospital, POB 340 (Haartmaninkatu 4), 00290 Helsinki (Finland); Department of Physics, University of Helsinki (Finland); Pakarinen, Sami, E-mail: sami.pakarinen@hus.fi [HUS Department of Cardiology, Helsinki University Central Hospital, POB 340 (Haartmaninkatu 4), 00290 Helsinki (Finland); Kivistö, Sari, E-mail: sari.kivisto@hus.fi [HUS Medical Imaging Center, Helsinki University Central Hospital, POB 340 (Haartmaninkatu 4), 00290 Helsinki (Finland); Holmström, Miia, E-mail: miia.holmstrom@hus.fi [HUS Medical Imaging Center, Helsinki University Central Hospital, POB 340 (Haartmaninkatu 4), 00290 Helsinki (Finland); Hänninen, Helena, E-mail: helena.hanninen@hus.fi [HUS Department of Cardiology, Helsinki University Central Hospital, POB 340 (Haartmaninkatu 4), 00290 Helsinki (Finland); Peltonen, Juha, E-mail: juha.peltonen@hus.fi [HUS Medical Imaging Center, Helsinki University Central Hospital, POB 340 (Haartmaninkatu 4), 00290 Helsinki (Finland); Department of Biomedical Engineering and Computational Science, School of Science, Aalto University, Helsinki (Finland); Lauerma, Kirsi, E-mail: kirsi.lauerma@hus.fi [HUS Medical Imaging Center, Helsinki University Central Hospital, POB 340 (Haartmaninkatu 4), 00290 Helsinki (Finland); Sipilä, Outi, E-mail: outi.sipila@hus.fi [HUS Medical Imaging Center, Helsinki University Central Hospital, POB 340 (Haartmaninkatu 4), 00290 Helsinki (Finland)

    2014-08-15

    Objectives: The aim of this study was to introduce a single centre “real life” experience of performing MRI examinations in clinical practice on patients with cardiac pacemaker systems. Additionally, we aimed to evaluate the safety of using a dedicated safety protocol for these patients. Materials and methods: We used a 1.5 T MRI scanner to conduct 68 MRI scans of different body regions in patients with pacing systems. Of the cardiac devices, 32% were MR-conditional, whereas the remaining 68% were MR-unsafe. We recorded the functional parameters of the devices prior, immediately after, and approximately one month after the MRI scanning, and compared the device parameters to the baseline values. Results: All MRI examinations were completed safely, and each device could be interrogated normally following the MRI. We observed no changes in the programmed parameters of the devices. For most of the participants, the distributions of the immediate and one-month changes in the device parameters were within 20% of the baseline values, although some changes approached clinically important thresholds. Furthermore, we observed no differences in the variable changes between MR-conditional and MR-unsafe pacing systems, or between scans of the thorax area and other scanned areas. Conclusion: MRI in patients with MR-conditional pacing systems and selected MR-unsafe systems could be performed safely under strict conditions in this study.

  4. Factors affecting the regulation of pacing: current perspectives

    Directory of Open Access Journals (Sweden)

    Mauger AR

    2014-09-01

    Full Text Available Alexis R Mauger Endurance Research Group, School of Sport and Exercise Sciences, Faculty of Science, University of Kent, Chatham, UK Abstract: During prolonged dynamic and rhythmic exercise, muscular pain and discomfort arises as a result of an increased concentration of deleterious metabolites. Sensed by peripheral nociceptors and transmitted via afferent feedback to the brain, this provides important information regarding the physiological state of the muscle. These sensations ultimately contribute to what is termed "exercise-induced pain". Despite being well recognized by athletes and coaches, and suggested to be integral to exercise performance, this construct has largely escaped attention in experimental work. This perspective article highlights the current understanding of pacing in endurance performance, and the causes of exercise-induced pain. A new perspective is described, which proposes how exercise-induced pain may be a contributing factor in helping individuals to regulate their work rate during exercise and thus provides an important construct in pacing. Keywords: pain, exercise-induced pain, discomfort, exercise performance, self-paced

  5. Optimizing classroom instruction through self-paced learning prototype

    Directory of Open Access Journals (Sweden)

    Romiro Gordo Bautista

    2015-09-01

    Full Text Available This study investigated the learning impact of self-paced learning prototype in optimizing classroom instruction towards students’ learning in Chemistry. Two sections of 64 Laboratory High School students in Chemistry were used as subjects of the study. The Quasi-Experimental and Correlation Research Design was used in the study: a pre-test was conducted, scored and analyzed which served as the basis in determining the initial learning schema of the respondents. A questionnaire was adopted to find the learning motivation of the students in science. Using Pearson-r correlation, it was found out that there is a highly significant relationship between their internal drive and their academic performance. Moreover, a post-test was conducted after self-paced learning prototype was used in the development of select topics in their curricular plot. It was found out that the students who experienced the self-paced learning prototype performed better in their academic performance as evidenced by the difference of their mean post-test results. ANCOVA results on the post-test mean scores of the respondents were utilized in establishing the causal-effect of the learning prototype to the academic performance of the students in Chemistry. A highly significant effect on their academic performance (R-square value of 70.7% and significant interaction of the models to the experimental grouping and mental abilities of the respondents are concluded in the study.

  6. MRI with cardiac pacing devices – Safety in clinical practice

    International Nuclear Information System (INIS)

    Objectives: The aim of this study was to introduce a single centre “real life” experience of performing MRI examinations in clinical practice on patients with cardiac pacemaker systems. Additionally, we aimed to evaluate the safety of using a dedicated safety protocol for these patients. Materials and methods: We used a 1.5 T MRI scanner to conduct 68 MRI scans of different body regions in patients with pacing systems. Of the cardiac devices, 32% were MR-conditional, whereas the remaining 68% were MR-unsafe. We recorded the functional parameters of the devices prior, immediately after, and approximately one month after the MRI scanning, and compared the device parameters to the baseline values. Results: All MRI examinations were completed safely, and each device could be interrogated normally following the MRI. We observed no changes in the programmed parameters of the devices. For most of the participants, the distributions of the immediate and one-month changes in the device parameters were within 20% of the baseline values, although some changes approached clinically important thresholds. Furthermore, we observed no differences in the variable changes between MR-conditional and MR-unsafe pacing systems, or between scans of the thorax area and other scanned areas. Conclusion: MRI in patients with MR-conditional pacing systems and selected MR-unsafe systems could be performed safely under strict conditions in this study

  7. Activity pacing for osteoarthritis symptom management: study design and methodology of a randomized trial testing a tailored clinical approach using accelerometers for veterans and non-veterans

    Directory of Open Access Journals (Sweden)

    Geisser Michael E

    2011-08-01

    people modulate their activity levels and reduce symptom flares caused by too much or too little activity. As a result of this trial, we will be able to determine if activity pacing is more effective than usual care, and among the intervention groups, if an individually tailored approach improves fatigue and pain more than a general activity pacing approach. Trial Registration ClinicalTrials.gov: NCT01192516

  8. Structured Approach vs. Self-Paced Modular Approach in Teaching Trigonometry

    Directory of Open Access Journals (Sweden)

    Rodin M. Paspasan

    2015-12-01

    Full Text Available The study aimed to determine which approach in the teaching of Mathematics allowed students to achieve a higher mathematical performance and to establish the learning styles of the students to showed greater confidence on a written posttest - the self-paced modular approach or the structured lecture demonstration based approach. The instruments used in the study are Trigonometry Achievement Test (PTAT designed by the researcher and the Grasha - Reichmann Student Learning Style Survey. Hence. the result shows on the test of significant difference on the respondents learning styles and level of performance established independent learning conditions and demonstrate remarkably higher mathematical performance, respectively. In the light of the statistical analysis and the findings of the study, it could be generalized that SPMA made the students learning styles more independent because they prefer to work at their own pace. Hence, SPMA help them also improve their level of performance in relation to plane trigonometry regardless of their mathematical abilities compared to structured approach. Along these lines, the subsequent recommendations are presented for consideration: The teachers should use collective learning style inventories so that students remain interested throughout their mathematics course. And should use SPMA in teaching trigonometry and other disciplines in the field of mathematics.

  9. Cardiac resynchronization therapy delivered via a multipolar left ventricular lead is associated with reduced mortality and elimination of phrenic nerve stimulation: long-term follow-up from a multicenter registry

    OpenAIRE

    Behar, JM; Bostock, J; Zhu Li, AP; Chin, HM; Jubb, S; Lent, E; Gamble, J; Foley, PW; Betts, TR; Rinaldi, CA; Herring, N.

    2015-01-01

    INTRODUCTION: Cardiac resynchronization therapy (CRT) using quadripolar left ventricular (LV) leads provides more pacing vectors compared to bipolar leads. This may avoid phrenic nerve stimulation (PNS) and allow optimal lead placement to maximize biventricular pacing. However, a long-term improvement in patient outcome has yet to be demonstrated. METHODS: A total of 721 consecutive patients with conventional CRTD criteria implanted with quadripolar (n = 357) or bipolar (n = 364) LV leads wer...

  10. Ecuador steps up pace of oil development activity

    International Nuclear Information System (INIS)

    This paper reports that oil companies operating in Ecuador plan to quicken the pace of oil development this year. After delays in 1991, companies plan a series of projects to develop reserves discovered the past 3 years estimated at more than 600 million bbl. Oil and Gas Journal estimated Ecuador's proved crude reserves at 1.55 billion bbl as of Jan. 1, 1992. The development push is part of a larger effort needed to ensure Ecuador's status as an oil exporter into the next century. Ecuador is the smallest crude oil producer and exporter in the Organization of Petroleum Exporting Countries

  11. Ventricular Septal Perforation after Biventricular Takotsubo Cardiomyopathy Successfully Repaired with an Amplatzer Device: First Report in the Literature

    Science.gov (United States)

    Rodríguez, Alfredo E.; Fernandez-Pereira, Carlos; Mieres, Juan; Ascarrunz, Diego; Gabe, Eduardo; Rodríguez-Granillo, Alfredo Matías; Frattini, Romina; Stuzbach, Pablo

    2016-01-01

    A 79-year-old female was admitted with sudden onset dyspnea, mild oppressive chest pain, and severe anxiety disorder. Patient had history of hypertension, dyslipidemia, smoking, and chronic obstructive pulmonary disease. On admission blood pressure was 160/90 and heart rate was 130 bpm. Transthoracic echocardiography (TE) and contrast tomography showed a thin septum with an abnormal left and right ventricular contraction with an “apical ballooning” pattern and mild increase of cardiac enzymes. At the 4th day of admission, the patient presented symptoms and signs of congestive heart failure and developed cardiogenic shock. EKG showed an inversion of T waves in all precordial leads. In a new TE, a ventricular septal perforation (VSP) in the apical portion of the septum was seen. Coronary angiogram showed angiographically “normal” coronary arteries. With a diagnosis of VSP in takotsubo cardiomyopathy, a percutaneous procedure to repair the VSP was performed 11 days after admission. The VSP was closed with an Amplatzer device. TE performed 24 hours after showed significant improvement of ventricular function and good apposition of the Amplatzer device. Three days later she was discharged from the hospital. To our knowledge, this is the first reported case of a VSP in a TCM repaired percutaneously with an occluder device.

  12. The influence of collective behaviour on pacing in endurance competitions

    Directory of Open Access Journals (Sweden)

    Andrew eRenfree

    2015-12-01

    Full Text Available A number of theoretical models have been proposed to explain pacing strategies in individual competitive endurance events. These have typically related to internal regulatory processes informing the making of decisions relating to muscular work rate. Despite a substantial body of research investigating the influence of collective group dynamics on individual behaviours in various animal species, this issue has not been comprehensively studied in individual athletic events. This is surprising given that athletes directly compete in close proximity to one another, and that collective behaviour has also been observed in other human environments. Whilst reasons for adopting collective behaviour are not fully understood, it is thought to result from individual agents following simple local rules resulting in seemingly complex large systems acting to confer some biological advantage to the collective as a whole. Although such collective behaviours may generally be beneficial, endurance events are complicated by the fact that increasing levels of physiological disruption as activity progresses may compromise the ability of individuals to continue to interact with other group members. This could result in early fatigue and relative underperformance due to suboptimal utilisation of physiological resources by some athletes. Alternatively, engagement with a collective behaviour may benefit all due to a reduction in the complexity of decisions to be made and a subsequent reduction in cognitive loading and mental fatigue. This paper seeks evidence for collective behaviour in previously published analyses of pacing behaviour and proposes mechanisms through which it could potentially be either beneficial, or detrimental to individual performance.

  13. Social Interaction in Self-paced Distance Education

    Directory of Open Access Journals (Sweden)

    Terry Anderson

    2015-02-01

    Full Text Available In this paper we present a case study of a self-paced university course that was originally designed to support independent, self-paced study at distance. We developed a social media intervention, in design-based research terms, that allows these independent students to contribute archived content to enhance the course, to engage in discussions with other students and to share as little or as much personal information with each other as they wished. We describe the learning design for the intervention and present survey data of student and tutor perception of value and content analysis of the archived contributions. The results indicate that the intervention was positively received by tutors and by the majority (but not all students and that the archive created by the students’ contributions was adding value to the course. We conclude that the intervention was a modest, yet manageable example of a learning enhancement to a traditional cognitive-behavioral, course that has positive impact and potential with little negative impact on workload.

  14. Data reproducibility of pace strategy in a laboratory test run.

    Science.gov (United States)

    de França, Elias; Xavier, Ana Paula; Hirota, Vinicius Barroso; Côrrea, Sônia Cavalcanti; Caperuto, Érico Chagas

    2016-06-01

    This data paper contains data related to a reproducibility test for running pacing strategy in an intermittent running test until exhaustion. Ten participants underwent a crossover study (test and retest) with an intermittent running test. The test was composed of three-minute sets (at 1 km/h above Onset Blood Lactate Accumulation) until volitional exhaustion. To assess pace strategy change, in the first test participants chose the rest time interval (RTI) between sets (ranging from 30 to 60 s) and in the second test the maximum RTI values were either the RTI chosen in the first test (maximum RTI value), or less if desired. To verify the reproducibility of the test, rating perceived exertion (RPE), heart rate (HR) and blood plasma lactate concentration ([La]p) were collected at rest, immediately after each set and at the end of the tests. As results, RTI, RPE, HR, [La]p and time to exhaustion were not statistically different (p>0.05) between test and retest, as well as they demonstrated good intraclass correlation. PMID:27081672

  15. Controlling Spiral Dynamics in Excitable Media by a Weakly Localized Pacing

    Institute of Scientific and Technical Information of China (English)

    LI Bing-Wei; SUN Li-Li; CHEN Bin; YING He-Ping

    2007-01-01

    @@ Spiral dynamics controlled by a weakly localized pacing around the spiral tip is investigated. Numerical simulations show two distinct characteristics when the pacing is applied with the weak amplitude for suitable frequencies:for a rigidly rotating spiral, a transition from rigid rotation to meandering motion is observed, and for unstable spiral waves, spiral breakup can be prevented. Successfully preventing spiral breakup is relevant to the modulation of the tip trajectory induced by a localized pacing.

  16. Two unsung heroes of closed-chest cardiac pacing: Green and McWilliam.

    Science.gov (United States)

    Geddes, L A

    1994-07-01

    In the latter half of the last century, cardiorespiratory arrest was not uncommon due to the anesthetic used (chloroform). Animal studies showed that the heart could be paced. One physician (Green) resuscitated 5 of 7 cardiac arrest patients with single stimuli applied to body surface electrodes. Another (McWilliam) issued a proposal for adoption of closed-chest pacing and provided information on the procedure. The following historical footnote describes these pioneering events in the history of cardiac pacing. PMID:7937239

  17. Effects of Amiodarone plus Losartan on Electrical Remodeling in Rapid Atrial Pacing in Rabbits

    Institute of Scientific and Technical Information of China (English)

    Liye Wei; Yue Xia; Guoqing Qi; Qingwen Zhang

    2008-01-01

    Objectives To investigate the electrical remodeling and the effects of amiodarone and losartan on electrical remode-ling in rapid atrial pacing on rabbit model. Methods 40 normal rabbits were randomly divided into 4 groups: the sa-line group (control group), amiodarone group, losartan group, ami + los group. All rabbits were raised drugs in a week. The atrial effective refractory period (AERP) was measured. Then, take a rapid atrial pacing (600 bpm) and the AERP was measured after 0. 5, 1, 2, 4, 6 and 8 hours pacing and 30 minutes after the termination of rapid pacing. Results ① In control group, after 8 hours rapid pacing, AERP 200 and AERP 150 were significantly shortened 16. 11%± 3. 1% (P <0. 01) and 9. 99%±4. 2% (P <0. 01). And the degree of AERP shortening induced by rapid pacing was greater at basic cycle lengths of 200 ms (BCL200) than that at BCL150. The AERP of amiodarone, losartan group and anti + los group were not shortened during rapid pacing.② In the control group, after the termination of rapid pacing, the AERP gradually increased. The AERP at all of the BCLS examined recovered to almost the 95.78% and 96. 76% of baseline values within the first 10 minutes and recovered to almost the 99. 07% and 99. 39% of baseline values within the first 30 minutes. Condusions Short-term atrial rapid pacing can induce the atrial electrical remodeling. Amiodarone and losartan can prevent the electrical remodeling.

  18. 1974 Arizona P.A.C.E. participation.

    Science.gov (United States)

    Zabezensky, F

    1976-12-01

    Members of the Arizona State Society for Medical Technology were contacted to ascertain their knowledge of the P.A.C.E. program as well as to obtain release of the transcripts for those who participated during 1974. Observations regarding reported credits were noted. The Analysis of Variance test with Scheffe comparison was utilized to determine if any characteristic accounted for the difference in total continuing education hours reported. It was concluded that residence location, marital status, sex, age, degree level, length of membership in ASMT, years experience, employment extent, place of employment, and number of beds at place of employment had no significant effect on the total hours reported. A significant difference in total hours reported was noted for those individuals who reported either CEU or college credits. A significant difference was also noted in the total hours reported with respect to job description. PMID:998653

  19. PACE: A dynamic programming algorithm for hardware/software partitioning

    DEFF Research Database (Denmark)

    Knudsen, Peter Voigt; Madsen, Jan

    1996-01-01

    This paper presents the PACE partitioning algorithm which is used in the LYCOS co-synthesis system for partitioning control/dataflow graphs into hardware and software parts. The algorithm is a dynamic programming algorithm which solves both the problem of minimizing system execution time with a...... hardware area constraint and the problem of minimizing hardware area with a system execution time constraint. The target architecture consists of a single microprocessor and a single hardware chip (ASIC, FPGA, etc.) which are connected by a communication channel. The algorithm incorporates a realistic...... communication model and thus attempts to minimize communication overhead. The time-complexity of the algorithm is O(n2·𝒜) and the space-complexity is O(n·𝒜) where 𝒜 is the total area of the hardware chip and n the number of code fragments which may be placed in either hardware or software...

  20. Il cimitero è morto. Pace all’anima sua

    Directory of Open Access Journals (Sweden)

    Andrea Marcuccetti

    2012-06-01

    Full Text Available L’immagine che si ha di un cimitero è quella che deriva dal modello ottocentesco, per tanti anni rimasto matrice dei cimiteri attuali. Ha senso ancora oggi progettare cimiteri, in una società sempre più digitale e virtuale, dove il ricordo, la memoria sono sempre meno legati al luogo di sepoltura, dove le direttive napoleoniche risultano superate e non più rispondenti alla visione tecnologica del mondo in cui viviamo? È il momento di cominciare a ripensare il concetto stesso di cimitero, oltre la realtà che lo configura come un  luogo relegato in un recinto. Che i cimiteri stiano morendo è un dato di fatto. La loro decomposizione è già cominciata nelle grandi metropoli, impensabile ma inevitabile. Bisogna cominciare a farsene una ragione, com’è inteso oggi: il cimitero è morto. Pace all’anima sua.

  1. Seasonal Pacing - Match Importance Affects Activity in Professional Soccer

    Science.gov (United States)

    Link, Daniel; de Lorenzo, Michael F.

    2016-01-01

    This research explores the influence of match importance on player activity in professional soccer. Therefore, we used an observational approach and analyzed 1,211 matches of German Bundesliga and 2nd Bundesliga. The importance measurement employed is based on post season consequences of teams involved in a match. This means, if a match result could potentially influence the final rank, and this rank would lead to different consequences for a team, such as qualification for Champions League opposed to qualification for Europe League, then this match is classified as important; otherwise not. Activity was quantified by TOTAL DISTANCE COVERED, SPRINTS, FAST RUNS, DUELS, FOULS and ATTEMPTS. Running parameters were recorded using a semi-automatic optical tracking system, while technical variables were collected by professional data loggers. Based on our importance classification, low important matches occurred at the beginning of round 29. A two-way ANOVA indicates significantly increased FAST RUNS (+4%, d = 0.3), DUELS (+16%, d = 1.0) and FOULS (+36%, d = 1.2) in important matches compared to low important ones. For FAST RUNS and FOULS, this effect only exists in Bundesliga. A comparison of the two leagues show that TOTAL DISTANCE COVERED (+3%, d = 0.9), SPRINTS (+25%, d = 1.4) and FAST RUNS (+15%, d = 1.4) are higher compared to 2nd Bundesliga, whilst FOULS is less in Bundesliga (-7%, d = 0.3). No difference in player activity was found between matches at the beginning of a season (round 1–6) and at the end of a season (round 29–34). We conclude that match importance influences player activity in German professional soccer. The most reasonable explanation is a conscious or unconscious pacing strategy, motivated by preserving abilities or preventing injury. Since this tendency mainly exists in Bundesliga, this may suggest that more skilled players show a higher awareness for the need of pacing. PMID:27281051

  2. Seasonal Pacing - Match Importance Affects Activity in Professional Soccer.

    Science.gov (United States)

    Link, Daniel; de Lorenzo, Michael F

    2016-01-01

    This research explores the influence of match importance on player activity in professional soccer. Therefore, we used an observational approach and analyzed 1,211 matches of German Bundesliga and 2nd Bundesliga. The importance measurement employed is based on post season consequences of teams involved in a match. This means, if a match result could potentially influence the final rank, and this rank would lead to different consequences for a team, such as qualification for Champions League opposed to qualification for Europe League, then this match is classified as important; otherwise not. Activity was quantified by TOTAL DISTANCE COVERED, SPRINTS, FAST RUNS, DUELS, FOULS and ATTEMPTS. Running parameters were recorded using a semi-automatic optical tracking system, while technical variables were collected by professional data loggers. Based on our importance classification, low important matches occurred at the beginning of round 29. A two-way ANOVA indicates significantly increased FAST RUNS (+4%, d = 0.3), DUELS (+16%, d = 1.0) and FOULS (+36%, d = 1.2) in important matches compared to low important ones. For FAST RUNS and FOULS, this effect only exists in Bundesliga. A comparison of the two leagues show that TOTAL DISTANCE COVERED (+3%, d = 0.9), SPRINTS (+25%, d = 1.4) and FAST RUNS (+15%, d = 1.4) are higher compared to 2nd Bundesliga, whilst FOULS is less in Bundesliga (-7%, d = 0.3). No difference in player activity was found between matches at the beginning of a season (round 1-6) and at the end of a season (round 29-34). We conclude that match importance influences player activity in German professional soccer. The most reasonable explanation is a conscious or unconscious pacing strategy, motivated by preserving abilities or preventing injury. Since this tendency mainly exists in Bundesliga, this may suggest that more skilled players show a higher awareness for the need of pacing. PMID:27281051

  3. Self-Paced Advanced Individual Training (AIT) and Duty Assignment Procedures.

    Science.gov (United States)

    Hunter, Harold; Wagner, Harold

    A study was made to (a) describe how self-paced Military Occupational Specialty (MOS) training affects the Army assignment system; (b) identify ways the existing assignment system can accommodate individualized instruction; and (c) suggest modifications to the assignment system to provide better integration of self-paced training with assignment…

  4. PACE: A test bed for the dynamics and control of flexible multibody systems

    Science.gov (United States)

    Kwak, Moon K.; Smith, Monty J.; Das, Alok

    1993-01-01

    The Phillips Laboratory at Edwards AFB has constructed a test bed for the validation and comparison of modeling and control theories for the dynamics and control of flexible multibody systems. This project is called the Planar Articulating Controls Experiment (PACE). This paper presents the experimental apparatus for PACE and the problem formulation. An in-depth analysis on DC motor dynamics was also performed.

  5. Research on Electrical Remodeling After Short Term Pacing in Canine Model

    Institute of Scientific and Technical Information of China (English)

    Kebbati A Hafid; Huang Congxin; Wang Xi; Zhao Qingyan

    2007-01-01

    Objectives To evaluate the changes in atrial effective refractory period (AERP) proprieties and in ionic currents in PVs myocytes from dogs subjected to rapid atrial pacing in PVs and right atrial appendage (RAA) and to relate these changes to the ability to induce AF. Methods Twelve mongrel dogs in normal sinus rhythm were paced from the superior left PVs or RAA at 500 bpm for 4 hours. Electrophysiologic studies conducted to determine changes in AERP, dispersion and rhythm. Ionic currents were studies with the patch clamp technique in single PVs myocytes in sham operated dogs and compared with those from PVs pacing and RAA pacing groups. Results The presence of rapid atrial pacing was associated with a marked shortening in AERP in both PVs and RAA pacing group with a marked increase of AERP dispersion in PVs pacing. Both L-type calcium current (ICa, L) and the transient outward current (Ito)were reduced in both groups with an increased significance in PVs pacing group. The density of ICa-L WaS decreased significantly from ( - 6.03 ± 0.63 ) pA/pF in the control group to ( -3.21±0.34) pA/pF in PVs pacing group and ( - 4,75 ± 0.41 ) pA/pF in RAA pacing group (n = 6, P<0.05) while the density of Ito was decreased significantly from (8.45±0.71 ) pA/pF in the control group to (5.21 ±0.763 ) pA/pF in PVs pacing group and (6,84 ± 0.69) pA/pF in RAA pacing group (n = 6, P<0.05). Conclusions Our findings provide likely ionic mechanisms of shortened repolarization in induced atrial tachycardia with a decrease in Ica,L and Ito current densities which is the likely mechanism for a decrease in Action potential duration (APD) rate adaptation in the canine rapid pacing model more pronounced in PVs pacing group underlying the crucial role of PVs in initiating AF.

  6. Temporary neonatal atrial pacing through the umbilical venous route: A novel technique

    Directory of Open Access Journals (Sweden)

    Hiren N Doshi

    2011-01-01

    Full Text Available Atrial pacing in the neonate is rarely done due to constraints of equipment, technical knowhow, and risk of complications. We describe a novel method of atrial pacing in the new born using equipment readily available in any intensive care unit. Atrial pacing can be achieved using an adult bipolar pacing wire directly introduced through the umbilical venous route. We have used this method in 5 neonates, and achieved atrial capture in 4 patients. Temporary atrial pacing is a therapeutic option in a few neonatal arrhythmias, such as atrial flutter, a few types of re-entrant tachycardias, such as accessory pathway mediated tachycardia and junctional reciprocating tachycardia, and has a limited role in cardiopulmonary resuscitation where sinoatrial node dysfunction is suspected.

  7. Effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony

    Institute of Scientific and Technical Information of China (English)

    支力大; 华伟; 张澍; 史蓉芳; 王方正; 陈新

    2004-01-01

    Background Right ventricular apical pacing has been reported to reduce cardiac performance. But there are few reports on the effects of dual chamber (DDD) pacing on cardiac function compared to sinus rhythm. In this study, we evaluated the effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony using equilibrium radionuclide angiography.Methods Ten patients implanted with a right atrial and ventricular DDD pacemaker underwent equilibrium radionuclide angiography. The scintigraphic data were obtained during sinus rhythm and pacing rhythm. Cardiac function parameters were obtained semimanually. Phase analysis was used to study the ventricular activation sequence and ventricular synchrony.Results The left ventricular 1/3 ejection fraction decreased significantly during pacing compared with that during sinus rhythm[(23.4 ±6.1)% vs(27.7 ±4.5)%, P =0.01]. Regional ejection fraction also decreased during pacing, although the difference was not statistically significant. Phase analysis showed that the right ventricle was activated earlier than the left ventricle during pacing, and that the phase shift was significantly greater during pacing than that during sinus rhythm[64.13°±16.80° vs 52.88°± 9.26°, P =0.007]. The activation of both ventricles occurred simultaneously during sinus rhythm, with the activation sequence from proximal septum or base of left ventricle to apex. The earliest activation during pacing occurred at the right ventricular apex, and subsequently spread to the base and left ventricle.Conclusion Right atrial and ventricular DDD pacing impairs left ventricular systolic function and ventricular synchrony.

  8. Therapeutic efficacy of digital music gastric electrical pacing for refractory functional dyspepsia concomitant with non-erosive reflux disease

    Directory of Open Access Journals (Sweden)

    Ya-mei RAN

    2015-04-01

    Full Text Available Objective To study the clinical efficacy of digital music gastric electrical pacing for refractory functional dyspepsia concomitant with non-erosive reflux disease, and its effects on mental health and life-quality of the patients. Methods According to the Rome Ⅲ criteria and Montreal consensus in diagnosis of gastroesophageal reflux disease, 50 patients with concomitant refractory functional dyspepsia and non-erosive reflux disease were recruited. The clinical efficacy of digital music gastric electrical pacing were evaluated using the score of clinical symptoms before treatment and 15 days after treatment, and the mental health and life-quality of patients were assessed using symptom checklist 90. Results Main symptoms, including upper abdominal pain, abdominal fullness, early satiety, belching, hiccup, nausea, heartburn, acid reflux (daytime, nocturnal acid reflux, loss of appetite and sleep, were significantly improved 15 days after treatment compared with those of pre-treatment, and there were statistically significant differences (all P<0.005. The significant response rate/response rate (efficacy rate were 59.0%/100.0%, 59.3%/96.3%, 47.0%/94.1%, 61.3%/96.8 %, 86.7%/100.0%, 80.0%/100.0%, 64.3%/92.9%, 73.7%/89.5%, 64.3%/85.7%, 90.0%/90.0%, 36.7%/93.3% respectively. After treatment for 15 days, the overall response rate of symptom relief was 94.4% in patients and the overall significant response rate was 65.7%. The symptom scores of somatization, obsessive-compulsiveness, depression, and anxiety were significantly improved, and the differences were statistically significant (all P<0.01. Conclusion The clinical efficacy of digital music gastric electrical pacing is significant for refractory functional dyspepsia concomitant with nonerosive reflux disease, and it is expected to be a new option for the treatment of this disease complex. DOI: 10.11855/j.issn.0577-7402.2015.03.08

  9. Observation of blood B-type natriuretic peptide level changes in different periods and different cardiac pacing modes

    Institute of Scientific and Technical Information of China (English)

    WANG Ru-xing; LI Xiao-rong; JIANG Wen-ping; LIU Zhi-hua; YANG Xiang-jun; XIAO Chun-hui; SHAO Li-zheng; ZHU Jian-qiu

    2005-01-01

    @@ In recent years, the indications of cardiac pacing have extended continuously with the rapid development of pacing technique. Pacemaker treatment has not only limited in arrhythmias of bradycardia and the number of pacemaker treatment has increased year by year.

  10. Temporary pace makers implantation: do we need fluoroscopy

    International Nuclear Information System (INIS)

    Temporary pace maker (TPM) implantation is done mostly in emergency with assistance of fluoroscopy. Fluoroscopy has various constrains which may delay the procedure at different occasion. We are going to share our experience in TPM implantation without fluoroscopy from internal jugular vein. Methods: The case series study was conducted in Hayatabad Medical complex Peshawar from January 2011 to November 2011. Internal jugular vein was cannulated with 6 French sheaths in the supra-clavicular region with modified Seldinger technique. TPM wire connected to the TPM device and advanced in the sheath to the right ventricle. Position was confirmed from captured beat on monitor. There was no need of repositioning and lead remains stable. Results: Total 122 TPM leads were implanted in the study period. All patients were implanted from internal jugular vein. There were 71 male and 51 female patients. Among these patients 55 were in hemodynamically unstable state. The average time of implantation was less than 10 minutes. There was failure in one case. So the overall success rate was 99.180%. Conclusion: TPM implantation from the internal jugular vein even without fluoroscopy is safe, less time consuming and convenient. (author)

  11. Bioelectromagnetic localization of a pacing catheter in the heart

    International Nuclear Information System (INIS)

    The accuracy of localizing source currents within the human heart by non-invasive magneto- and electrocardiographic methods was investigated in 10 patients. A non-magnetic stimulation catheter inside the heart served as a reference current source. Biplane fluoroscopic imaging with lead ball markers was used to record the catheter position. Simultaneous multichannel magnetocardiographic (MCG) and body surface potential mapping (BSPM) recordings were performed during catheter pacing. Equivalent current dipole localizations were computed from MCG and BSPM data, employing standard and patient-specific boundary element torso models. Using individual models with the lungs included, the average MCG localization error was 7±3 mm, whereas the average BSPM localization error was 25±4 mm. In the simplified case of a single homogeneous standard torso model, an average error of 9±3 mm was obtained from MCG recordings. The MCG localization accuracies obtained in this study imply that the capability of multichannel MCG to locate dipolar sources is sufficient for clinical purposes, even without constructing individual torso models from x-ray or from magnetic resonance images. (author)

  12. Bioelectromagnetic localization of a pacing catheter in the heart

    Science.gov (United States)

    Pesola, K.; Nenonen, J.; Fenici, R.; Lötjönen, J.; Mäkijärvi, M.; Fenici, P.; Korhonen, P.; Lauerma, K.; Valkonen, M.; Toivonen, L.; Katila, T.

    1999-10-01

    The accuracy of localizing source currents within the human heart by non-invasive magneto- and electrocardiographic methods was investigated in 10 patients. A non-magnetic stimulation catheter inside the heart served as a reference current source. Biplane fluoroscopic imaging with lead ball markers was used to record the catheter position. Simultaneous multichannel magnetocardiographic (MCG) and body surface potential mapping (BSPM) recordings were performed during catheter pacing. Equivalent current dipole localizations were computed from MCG and BSPM data, employing standard and patient-specific boundary element torso models. Using individual models with the lungs included, the average MCG localization error was 7±3 mm, whereas the average BSPM localization error was 25±4 mm. In the simplified case of a single homogeneous standard torso model, an average error of 9±3 mm was obtained from MCG recordings. The MCG localization accuracies obtained in this study imply that the capability of multichannel MCG to locate dipolar sources is sufficient for clinical purposes, even without constructing individual torso models from x-ray or from magnetic resonance images.

  13. Council sets pace for '82-'84 action

    Science.gov (United States)

    The December 1982 meeting of the AGU Council, the first in the 1982-1984 biennium, has set a new pace. It is the first Council Meeting in the memory of any of those participating at which every Council member was present in person. This record attests to the importance Section presidents and president-elects place on their responsibilities as representatives of their sections and as members of what in effect is AGU's Board of Directors; and it is a further tribute to the value they place on AGU.Both the Council and the AGU Executive Committee held their meetings on December 9, 1982, during the Fall Meeting in San Francisco. President Van Allen, President-elect Drake, General Secretary Meredith, Foreign Secretary Kisslinger, and Executive Director Spilhaus constitute the Executive Committee. The full Council includes the Executive Committee and the President and President-elect of each Section. At its meetings the Council usually addresses administrative matters such as budgeting, examines existing operations, and considers proposed new programs. The Executive Committee acts on behalf of the Council between Council meetings; it is specifically charged with approving Chapman conferences, the cosponsorship of other meetings, and several other largely administrative actions.

  14. Cardiomyopathy induced by artificial cardiac pacing: myth or reality sustained by evidence?

    Directory of Open Access Journals (Sweden)

    Andrés Di Leoni Ferrari

    2014-09-01

    Full Text Available Implantable cardiac pacing systems are a safe and effective treatment for symptomatic irreversible bradycardia. Under the proper indications, cardiac pacing might bring significant clinical benefit. Evidences from literature state that the action of the artificial pacing system, mainly when the ventricular lead is located at the apex of the right ventricle, produces negative effects to cardiac structure (remodeling, dilatation and function (dissinchrony. Patients with previously compromised left ventricular function would benefit the least with conventional right ventricle apical pacing, and are exposed to the risk of developing higher incidence of morbidity and mortality for heart failure. However, after almost 6 decades of cardiac pacing, just a reduced portion of patients in general would develop these alterations. In this context, there are not completely clear some issues related to cardiac pacing and the development of this cardiomyopathy. Causality relationships among QRS widening with a left bundle branch block morphology, contractility alterations within the left ventricle, and certain substrates or clinical (previous systolic dysfunction, structural heart disease, time from implant or electrical conditions (QRS duration, percentage of ventricular stimulation are still subjecte of debate. This review analyses contemporary data regarding this new entity, and discusses alternatives of how to use cardiac pacing in this context, emphasizing cardiac resynchronization therapy.

  15. Pacing-induced congenital heart defects assessed by OCT (Conference Presentation)

    Science.gov (United States)

    Ford, Stephanie M.; McPheeters, Matt T.; Wang, Yves T.; Gu, Shi; Doughman, Yong Qiu; Strainic, James P.; Rollins, Andrew M.; Watanabe, Michiko; Jenkins, Michael W.

    2016-03-01

    The role of hemodynamics in early heart development is poorly understood. In order to successfully assess the impact of hemodynamics on development, we need to monitor and perturb blood flow, and quantify the resultant effects on morphology. Here, we have utilized cardiac optical pacing to create regurgitant flow in embryonic hearts and OCT to quantify regurgitation percentage and resultant morphology. Embryonic quail in a shell-less culture were optically paced at 3 Hz (well above the intrinsic rate or 1.33-1.67 Hz) on day 2 of development (3-4 weeks human) for 5 minutes. The pacing fatigued the heart and led to a prolonged period (> 1 hour) of increased regurgitant flow. Embryos were kept alive until day 3 (cardiac looping - 4-5 weeks human) or day 8 (4 chambered heart - 8 weeks human) to quantify resultant morphologic changes with OCT. All paced embryos imaged at day 3 displayed cardiac defects. The extent of regurgitant flow immediately after pacing was correlated with cardiac cushion size 24-hours post pacing (p-value develop into abnormal valves and septa. Our model produces similar phenotypes as found in our fetal alcohol syndrome and velo-cardio-facial/DiGeorge syndrome models suggesting that hemodynamics plays a role in these syndromes as well. Utilizing OCT and optical pacing to understand hemodynamics in development is an important step towards determining CHD mechanisms and ultimately developing earlier treatments.

  16. Factors Affecting the Study Pace of First-Year Law Students: In Search of Study Counselling Tools

    Science.gov (United States)

    Haarala-Muhonen, Anne; Ruohoniemi, Mirja; Lindblom-Ylanne, Sari

    2011-01-01

    This study explores factors affecting the study pace of law students during their first academic year. The participants comprised two student groups: those whose number of study credits were the lowest and highest. Altogether, 25 students (11 with a slow and 14 with a fast study pace) were interviewed. The factors affecting study pace mentioned by…

  17. Assessment of Ventricular Dissynchrony in Right Ventricular Single Chamber Pacing using Echocardiografic Parameters

    Directory of Open Access Journals (Sweden)

    Vita I

    2014-04-01

    Full Text Available Background: Right ventricular apical pacing has been used since the early years of pace-makers, despite the fact that it determined nonphysiological ventricular depolarization. As medical technologies developed, septal lead implantation became feasible, in order to outrun the above mentioned inconveniences. The question whether the apical or septal lead position is better still gives rise to a lot of controversies. Different echocardiographic parameters are currently used to assess the impact of specific sites of stimulation on ventricular function. The aim of the study was to determine which of the followed synchronicity parameters varied significantly during apical stimulation, compared to septal stimulation in patients requiring single chamber pacing.

  18. Optimal Cardiac Resynchronization Therapy Pacing Rate in Non-Ischemic Heart Failure Patients

    DEFF Research Database (Denmark)

    Ghotbi, Adam Ali; Sander, Mikael; Køber, Lars;

    2015-01-01

    BACKGROUND: The optimal pacing rate during cardiac resynchronization therapy (CRT) is unknown. Therefore, we investigated the impact of changing basal pacing frequencies on autonomic nerve function, cardiopulmonary exercise capacity and self-perceived quality of life (QoL). METHODS: Twelve CRT...... by microneurography (MSNA), peak oxygen consumption (pVO2), N-terminal pro-brain natriuretic peptide (p-NT-proBNP), echocardiography and QoL. RESULTS: DDD-80 pacing for 3 months increased the mean heart rate from 77.3 to 86.1 (p = 0.001) and reduced sympathetic activity compared to DDD-60 (51±14 bursts/100 cardiac...

  19. Obliquity-paced Pliocene West Antarctic ice sheet oscillations

    Science.gov (United States)

    Naish, T.; Powell, R.; Levy, R.; Wilson, G.; Scherer, R.; Talarico, F.; Krissek, L.; Niessen, F.; Pompilio, M.; Wilson, T.; Carter, L.; DeConto, R.; Huybers, P.; McKay, R.; Pollard, D.; Ross, J.; Winter, D.; Barrett, P.; Browne, G.; Cody, R.; Cowan, E.; Crampton, J.; Dunbar, G.; Dunbar, N.; Florindo, F.; Gebhardt, C.; Graham, I.; Hannah, M.; Hansaraj, D.; Harwood, D.; Helling, D.; Henrys, S.; Hinnov, L.; Kuhn, G.; Kyle, P.; Laufer, A.; Maffioli, P.; Magens, D.; Mandernack, K.; McIntosh, W.; Millan, C.; Morin, R.; Ohneiser, C.; Paulsen, T.; Persico, D.; Raine, I.; Reed, J.; Riesselman, C.; Sagnotti, L.; Schmitt, D.; Sjunneskog, C.; Strong, P.; Taviani, M.; Vogel, S.; Wilch, T.; Williams, T.

    2009-01-01

    Thirty years after oxygen isotope records from microfossils deposited in ocean sediments confirmed the hypothesis that variations in the Earth's orbital geometry control the ice ages, fundamental questions remain over the response of the Antarctic ice sheets to orbital cycles. Furthermore, an understanding of the behaviour of the marine-based West Antarctic ice sheet (WAIS) during the 'warmer-than-present' early-Pliocene epoch (???5-3 Myr ago) is needed to better constrain the possible range of ice-sheet behaviour in the context of future global warming. Here we present a marine glacial record from the upper 600 m of the AND-1B sediment core recovered from beneath the northwest part of the Ross ice shelf by the ANDRILL programme and demonstrate well-dated, ???40-kyr cyclic variations in ice-sheet extent linked to cycles in insolation influenced by changes in the Earth's axial tilt (obliquity) during the Pliocene. Our data provide direct evidence for orbitally induced oscillations in the WAIS, which periodically collapsed, resulting in a switch from grounded ice, or ice shelves, to open waters in the Ross embayment when planetary temperatures were up to ???3??C warmer than today and atmospheric CO 2 concentration was as high as ???400 p.p.m.v. (refs 5, 6). The evidence is consistent with a new ice-sheet/ice-shelf model that simulates fluctuations in Antarctic ice volume of up to +7 m in equivalent sea level associated with the loss of the WAIS and up to +3 m in equivalent sea level from the East Antarctic ice sheet, in response to ocean-induced melting paced by obliquity. During interglacial times, diatomaceous sediments indicate high surface-water productivity, minimal summer sea ice and air temperatures above freezing, suggesting an additional influence of surface melt under conditions of elevated CO2. ??2009 Macmillan Publishers Limited. All rights reserved.

  20. Cloud Retrieval Information Content Studies with the Pre-Aerosol, Cloud and ocean Ecosystem (PACE) Ocean Color Imager (OCI)

    Science.gov (United States)

    Coddington, Odele; Platnick, Steven; Pilewskie, Peter; Schmidt, Sebastian

    2016-04-01

    The NASA Pre-Aerosol, Cloud and ocean Ecosystem (PACE) Science Definition Team (SDT) report released in 2012 defined imager stability requirements for the Ocean Color Instrument (OCI) at the sub-percent level. While the instrument suite and measurement requirements are currently being determined, the PACE SDT report provided details on imager options and spectral specifications. The options for a threshold instrument included a hyperspectral imager from 350-800 nm, two near-infrared (NIR) channels, and three short wave infrared (SWIR) channels at 1240, 1640, and 2130 nm. Other instrument options include a variation of the threshold instrument with 3 additional spectral channels at 940, 1378, and 2250 nm and the inclusion of a spectral polarimeter. In this work, we present cloud retrieval information content studies of optical thickness, droplet effective radius, and thermodynamic phase to quantify the potential for continuing the low cloud climate data record established by the MOderate Resolution and Imaging Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) missions with the PACE OCI instrument (i.e., non-polarized cloud reflectances and in the absence of midwave and longwave infrared channels). The information content analysis is performed using the GEneralized Nonlinear Retrieval Analysis (GENRA) methodology and the Collection 6 simulated cloud reflectance data for the common MODIS/VIIRS algorithm (MODAWG) for Cloud Mask, Cloud-Top, and Optical Properties. We show that using both channels near 2 microns improves the probability of cloud phase discrimination with shortwave-only cloud reflectance retrievals. Ongoing work will extend the information content analysis, currently performed for dark ocean surfaces, to different land surface types.

  1. Left ventricular pacing vector selection by novel echo-particle imaging velocimetry analysis for optimization of quadripolar cardiac resynchronization device: a case report

    OpenAIRE

    Martiniello, Alfonso/A. Roberto/R.; Pedrizzetti, Gianni/G.; Bianchi, Valter/V.; Tonti, Giovanni/G.; D’Onofrio, Antonio/A.; Caso, Pio/P.

    2016-01-01

    Background The availability of pacing configurations offered by quadripolar left ventricular leads could improve patients’ response to cardiac resynchronization therapy; however, the selection of an optimal setting remains a challenge. Echo-particle imaging velocimetry has shown that regional anomalies of synchrony/synergy of the left ventricle are related to the alteration, reduction, or suppression of the physiological intracavitary pressure gradients. These observations are also supported ...

  2. Brief Exposure to a Self-Paced Computer-Based Reading Programme and How It Impacts Reading Ability and Behaviour Problems

    OpenAIRE

    J Antony Hughes; Gordon Phillips; Phil Reed

    2013-01-01

    Basic literacy skills underlie much future adult functioning, and are targeted in children through a variety of means. Children with reading problems were exposed either to a self-paced computer programme that focused on improving phonetic ability, or underwent a classroom-based reading intervention. Exposure was limited to 3 40-min sessions a week, for six weeks. The children were assessed in terms of their reading, spelling, and mathematics abilities, as well as for their externalising and ...

  3. Estudo comparativo das estimulações ventricular direita e biventricular no pós-operatório de revascularização miocárdica

    Directory of Open Access Journals (Sweden)

    ALBUQUERQUE Luciano C.

    2002-01-01

    Full Text Available OBJETIVO: Nos anos recentes, a ressincronização ventricular tem sido proposta como adjuvante no tratamento da insuficiência cardíaca congestiva. O objetivo deste estudo é comparar as alterações eletrocardiográficas e o efeito hemodinâmico imediato das estimulações ventricular direita (EVD e biventricular (EBV, no pós-operatório de operação de revascularização miocárdica (CRM com circulação extracorpórea (CEC. CASUÍSTICA E MÉTODOS: Em um ensaio clínico cruzado, 13 pacientes com doença coronária multiarterial, e fração de ejeção inferior a 50%, foram submetidos a estimulação epicárdica temporária univentricular direita e biventricular, no 5° dia de pós-operatório. As variáveis analisadas foram duração do complexo QRS, dimensões do átrio esquerdo (AE e ventrículo esquerdo (VE, fração de encurtamento do VE (delta D e fração de ejeção do VE. Os grupos foram comparados através do teste de t de Student para amostras pareadas, considerando-se nível de significância de 0,05. RESULTADOS: A duração média do complexo QRS foi de 185±26 ms durante a EVD, e de 126±37 ms com a EBV (p<0,001. O diâmetro médio do AE com a EVD foi de 40±4 mm, e de 35±4 mm na EBV (p<0,001. As médias dos diâmetros diastólico e sistólico finais do VE foram, respectivamente, de 49±13 mm e 59±11 mm com a EVD, e de 42±12 mm e 52±10 mm durante a EBV (p<0,001. A delta D média do VE determinada pela EVD foi de 18±7%, e de 22±8% com a EBV (p=0,017. A fração de ejeção média do VE com a EVD foi de 33±14%, e de 46±17% durante a EBV (p<0,001. CONCLUSÃO: No modelo estudado, a estimulação biventricular temporária determinou melhora significativa do desempenho hemodinâmico, em comparação à estimulação ventricular direita, e um complexo QRS com duração próxima à fisiológica.

  4. A computer based, interactive, multimedia training module for self-paced learning

    International Nuclear Information System (INIS)

    Disadvantages of traditional safeguards inspectors training methods are outlined. A computer based, interactive, multimedia, self-paced training programme, called the CANDU power reactor training module (CPRTM) is described. 1 ref., 2 figs

  5. Photovoltaics (PV) as an Eligible Measure in Residential PACE Programs: Benefits and Challenges (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    Coughlin, J.

    2010-06-01

    Property Assessed Clean Energy (PACE) financing is one of several new financial models broadening access to clean energy by addressing the barrier of initial capital cost. The majority of the PACE programs in the market today include PV as an eligible measure. PV appeals to homeowners as a way to reduce utility bills, self-generate sustainable power, increase energy independence and demonstrate a commitment to the environment. If substantial state incentives for PV exist, PV projects can be economic under PACE, especially when partnered with good net metering policies. At the same time, PV is expensive relative to other eligible measures with a return on investment horizon that might exceed program targets. This fact sheet reviews the benefits and potential challenges of including PV in PACE programs.

  6. Cardiac pacing device therapy for atrial dysrhythmias: how does it work?

    Science.gov (United States)

    Irwin, Marleen E

    2004-01-01

    Atrial fibrillation (AF) is the most common dysrhythmia in North America. Paroxysmal or persistent AF affects an estimated 2.8 million individuals, causes significant morbidity, and is associated with 1 billion dollars in healthcare costs each year in the United States. An aging population, the prevalence of hypertension, and the emergence of heart failure as the final common pathway of heart disease finds us in an age where the incidence of AF is ever increasing and the management challenges are indeed an expanding clinical problem. Although guidelines for selection of the appropriate pacing mode have been published, device therapy for the control of AF and paroxysmal AF is an emerging clinical management strategy. In 2001 The American College of Cardiology (ACC)/American Heart Association (AHA) published a document to revise the 1998 guidelines for device therapy, and even now these guidelines require elucidation and inclusion for the use of cardiac pacing device therapy for the control of atrial dysrhythmia. Choosing a complex system, in particular for the patient with persistent and symptomatic atrial dysrhythmia, is a most intricate challenge for the healthcare professional and the healthcare system. Rate dependent effects on refractoriness, reduction of ectopy, remodeling of the substrate, and prevention of pauses have been described as the potential mechanisms responsible for the rhythmic control effect attributed to atrial pacing. However, while permanent cardiac pacing is required for patients with symptomatic bradycardia with atrioventricular block and AF, the concept of pacing for the primary prevention of AF is novel. Pacing algorithms, single site, biatrial, and dual-site atrial pacing and site-specific pacing have all been studied as substrate modulators to prevent recurrent atrial dysrhythmia.A dilemma exists surrounding the primary approach for the control of symptomatic AF with rapid ventricular response. The question remains: should it be to

  7. The effect of shared temporal cognitions and Pacing styles on intragroup conflict in portuguese healthcare teams

    OpenAIRE

    Queimado, Alexandra Coelho de Meireles de Oliveira

    2015-01-01

    Master in Human Resources Management This study aimed to evaluate the impact of two specific dimensions of time-related matters (shared temporal cognitions and pacing styles), as a cognitive contextual factor, on different types of team conflict. We hypothesized that the relationship between shared temporal cognitions and the different types of conflict is moderated by pacing styles. A total of 30 teams (245 individuals) participated in this study. All teams were part of different Portugue...

  8. The impact of the perception of rhythmic music on self-paced oscillatory movements

    OpenAIRE

    Peckel, Mathieu; Pozzo, Thierry; Bigand, Emmanuel

    2014-01-01

    Inspired by theories of perception-action coupling and embodied music cognition, we investigated how rhythmic music perception impacts self-paced oscillatory movements. In a pilot study, we examined the kinematic parameters of self-paced oscillatory movements, walking and finger tapping using optical motion capture. In accordance with biomechanical constraints accounts of motion, we found that movements followed a hierarchical organization depending on the proximal/distal characteristic of th...

  9. Study of Access and Quality of Care in For-Profit PACE

    OpenAIRE

    David Jones; Nancy Duda; Bob Schmitz; Sandi Nelson; Chelsea Swete; Alex Bryce; Jared Coopersmith; Karen CyBulski

    2013-01-01

    This report summarizes a study to address quality of and access to care for participants of for-profit Programs of All-Inclusive Care for the Elderly (PACE) organizations. The PACE model allows people who otherwise need a nursing home-level of care to remain in the community by providing health care and related support services, such as social supports, meals and chore services, and transportation.

  10. The impact of the perception of rhythmic music on oscillatory self-paced movements

    OpenAIRE

    Mathieu ePeckel; Thierry ePozzo; Emmanuel eBigand

    2014-01-01

    Inspired by theories of perception-action coupling and embodied music cognition, we investigated how rhythmic music perception impacts self-paced oscillatory movements. In a pilot study, we examined the kinematic parameters of self-paced oscillatory movements, walking and finger tapping using optical motion capture. In accordance with biomechanical constraints accounts of motion, we found that movements followed a hierarchical organization depending on the proximal/distal characteristic of th...

  11. Potassium exchange in the human heart during atrial pacing and myocardial ischaemia.

    OpenAIRE

    Webb, S C; Poole-Wilson, P. A.

    1986-01-01

    Potassium homoeostasis in the heart was studied during atrial pacing in 20 patients undergoing diagnostic coronary angiography. The potassium concentrations in the coronary sinus and a systemic artery were recorded continuously by means of catheter tip potassium electrodes. Ten patients with coronary artery disease and a positive exercise test developed chest pain and ST segment depression on the electrocardiogram during atrial pacing. Potassium concentrations in the coronary sinus rose initi...

  12. The effect of visitor number and spice provisioning in pacing expression by jaguars evaluated through a case study.

    Science.gov (United States)

    Vidal, L S; Guilherme, F R; Silva, V F; Faccio, M C S R; Martins, M M; Briani, D C

    2016-06-01

    Captive animals exhibit stereotypic pacing in response to multiple causes, including the inability to escape from human contact. Environmental enrichment techniques can minimize pacing expression. By using an individual-based approach, we addressed whether the amount of time two males and a female jaguar (Panthera onca) devote to pacing varied with the number of visitors and tested the effectiveness of cinnamon and black pepper in reducing pacing. The amount of time that all jaguars engaged in pacing increased significantly with the number of visitors. Despite the difference between the males regarding age and housing conditions, both devoted significantly less time to pacing following the addition of both spices, which indicates their suitability as enrichment techniques. Mean time devoted to pacing among the treatments did not differ for the female. Our findings pointed out to the validity of individual-based approaches, as they can reveal how suitable olfactory stimuli are to minimizing stereotypies irrespective of particular traits. PMID:26959957

  13. Colony pace: a life-history trait affecting social insect epidemiology.

    Science.gov (United States)

    Buechel, Séverine Denise; Schmid-Hempel, Paul

    2016-01-13

    Among colonies of social insects, the worker turnover rate (colony 'pace') typically shows considerable variation. This has epidemiological consequences for parasites, because in 'fast-paced' colonies, with short-lived workers, the time of parasite residence in a given host will be reduced, and further transmission may thus get less likely. Here, we test this idea and ask whether pace is a life-history strategy against infectious parasites. We infected bumblebees (Bombus terrestris) with the infectious gut parasite Crithidia bombi, and experimentally manipulated birth and death rates to mimic slow and fast pace. We found that fewer workers and, importantly, fewer last-generation workers that are responsible for rearing sexuals were infected in colonies with faster pace. This translates into increased fitness in fast-paced colonies, as daughter queens exposed to fewer infected workers in the nest are less likely to become infected themselves, and have a higher chance of founding their own colonies in the next year. High worker turnover rate can thus act as a strategy of defence against a spreading infection in social insect colonies. PMID:26763696

  14. Automatic artefact removal in a self-paced hybrid brain- computer interface system

    Directory of Open Access Journals (Sweden)

    Yong Xinyi

    2012-07-01

    Full Text Available Abstract Background A novel artefact removal algorithm is proposed for a self-paced hybrid brain-computer interface (BCI system. This hybrid system combines a self-paced BCI with an eye-tracker to operate a virtual keyboard. To select a letter, the user must gaze at the target for at least a specific period of time (dwell time and then activate the BCI by performing a mental task. Unfortunately, electroencephalogram (EEG signals are often contaminated with artefacts. Artefacts change the quality of EEG signals and subsequently degrade the BCI’s performance. Methods To remove artefacts in EEG signals, the proposed algorithm uses the stationary wavelet transform combined with a new adaptive thresholding mechanism. To evaluate the performance of the proposed algorithm and other artefact handling/removal methods, semi-simulated EEG signals (i.e., real EEG signals mixed with simulated artefacts and real EEG signals obtained from seven participants are used. For real EEG signals, the hybrid BCI system’s performance is evaluated in an online-like manner, i.e., using the continuous data from the last session as in a real-time environment. Results With semi-simulated EEG signals, we show that the proposed algorithm achieves lower signal distortion in both time and frequency domains. With real EEG signals, we demonstrate that for dwell time of 0.0s, the number of false-positives/minute is 2 and the true positive rate (TPR achieved by the proposed algorithm is 44.7%, which is more than 15.0% higher compared to other state-of-the-art artefact handling methods. As dwell time increases to 1.0s, the TPR increases to 73.1%. Conclusions The proposed artefact removal algorithm greatly improves the BCI’s performance. It also has the following advantages: a it does not require additional electrooculogram/electromyogram channels, long data segments or a large number of EEG channels, b it allows real-time processing, and c it reduces signal distortion.

  15. Diaphragmatic pacing stimulation in spinal cord injury: anesthetic and perioperative management

    Directory of Open Access Journals (Sweden)

    Miguel L. Tedde

    2012-11-01

    Full Text Available OBJECTIVE: The standard therapy for patients with high-level spinal cord injury is long-term mechanical ventilation through a tracheostomy. However, in some cases, this approach results in death or disability. The aim of this study is to highlight the anesthetics and perioperative aspects of patients undergoing insertion of a diaphragmatic pacemaker. METHODS: Five patients with quadriplegia following high cervical traumatic spinal cord injury and ventilator-dependent chronic respiratory failure were implanted with a laparoscopic diaphragmatic pacemaker after preoperative assessments of their phrenic nerve function and diaphragm contractility through transcutaneous nerve stimulation. ClinicalTrials.gov: NCT01385384. RESULTS: The diaphragmatic pacemaker placement was successful in all of the patients. Two patients presented with capnothorax during the perioperative period, which resolved without consequences. After six months, three patients achieved continuous use of the diaphragm pacing system, and one patient could be removed from mechanical ventilation for more than 4 hours per day. CONCLUSIONS: The implantation of a diaphragmatic phrenic system is a new and safe technique with potential to improve the quality of life of patients who are dependent on mechanical ventilation because of spinal cord injuries. Appropriate indication and adequate perioperative care are fundamental to achieving better results.

  16. Comparison of objective methods to classify the pattern of respiratory sinus arrhythmia during mechanical ventilation and paced spontaneous breathing

    International Nuclear Information System (INIS)

    Respiratory sinus arrhythmia (RSA) is a fluctuation of heart period that occurs during a respiratory cycle. It has been suggested that inspiratory heart period acceleration and expiratory deceleration during spontaneous ventilation (henceforth named positive RSA) improve the efficiency of gas exchange compared to the absence or the inversion of such a pattern (negative RSA). During mechanical ventilation (MV), for which maximizing the efficiency of gas exchange is of critical importance, the pattern of RSA is still the object of debate. In order to gain a better insight into this matter, we compared five different methods of RSA classification using the data of five mechanically ventilated piglets. The comparison was repeated using the data of 15 volunteers undergoing a protocol of paced spontaneous breathing, which is expected to result in a positive RSA pattern. The results showed that the agreement between the employed methods is limited, suggesting that the lack of a consensus about the RSA pattern during MV is, at least in part, of methodological origin. However, independently of the method used, the pattern of RSA within the respiratory cycle was not consistent among the subjects and conditions of MV considered. Also, the outcomes showed that even during paced spontaneous breathing a negative RSA pattern might be present, when a low respiratory frequency is imposed

  17. Using self-paced, `flipped' teaching to promote deep learning in an Earth Sciences programming course

    Science.gov (United States)

    Kalnins, L. M.

    2015-12-01

    Over the last year we implemented a complete restructuring of a second year Matlab-based course on numerical modelling of Earth processes, with changes aimed at 1) strengthening students' independence as programmers, 2) addressing student concerns about support in developing coding skills, and 3) improving key modelling skills such as choosing boundary conditions. To address this, we designed a mastery-based approach where students progress through a series of small programming projects at their own pace. As part of this, all lectures are `flipped' into short videos, allowing all contact hours to be spent on programming. The projects themselves are structured based on a `bottlenecks to learning' approach, explicitly separating out the steps of learning new commands and code structures, creating a conceptual and mathematical model of the problem, and development of more generic programmings skills such as debugging before asking the students to combine all of the above to build a numerical model of an Earth Sciences problem. Compared with the previous, traditionally taught cohort, student questionnaires show a strong improvement in overall satisfaction. Free text responses show a focus on learning for understanding, and that students particularly valued the encouragement to slow down and work towards understanding when they encountered a difficult topic, rather than being pressured by a set timetable to move on. Quantitatively, exam performance improved on key conceptual questions, such as boundary conditions and discretisation, and overall achievement also rose, with 25% of students achieving an `A+' standard of work. Many of the final projects also demonstrated programming and modelling skills that had not been directly taught, ranging from use of new commands to extension of techniques taught in 1D to the 2D case: strong confirmation of the independent skills we aimed to foster with this new approach.

  18. Pacing-induced ST segment deviation in patients with unstable angina: clinical, angiographic, and hemodynamic correlation.

    Science.gov (United States)

    Hussain, K M; Gould, L; Pomerantsev, E V; Angirekula, M; Bharathan, T

    1995-07-01

    To assess the clinical, coronary arteriographic, and hemodynamic differences between the unstable angina patients manifesting ST segment depression and those showing ST segment elevation as well as those demonstrating chest pain only without ST segment deviation during pacing, low-dose digital subtraction ventriculography was performed in 33 patients before and after abrupt cessation of atrial pacing during selective coronary arteriography. Transient ST segment depression during pacing was observed in 17 patients (52%), whereas 6 patients (18%) showed ST segment elevation; however, 10 patients (30%) did not manifest any ST segment deviation in spite of typical chest pain. Hypertension and a history of myocardial infarction were observed in a significantly higher (P < 0.05) proportion of patients with ST segment depression than in those with ST elevation. Patients who manifested ST segment depression during pacing had a higher incidence of triple-vessel disease (65 vs 17%; P < .05) as compared with the patients with ST segment elevation. Indirect evidence of intracoronary thrombi (complicated lesion, abrupt occlusion, and intraluminal filling defect) was noticed in a higher frequency (P < 0.05) in the group of patients with ST elevation during pacing. In patients with ST segment depression, no significant changes of global left ventricular (LV) functional parameters were observed. However, the length of the LV severe hypokinetic region was increased significantly (6.2 +/- 3.1 vs 23.5 +/- 6.2%; P < 0.005) during pacing in this group of patients. The shortening of the affected segments of the left ventricle was decreased significantly (52.3 +/- 3.6 vs 38.3 +/- 4.9%; P < 0.05) in these patients during pacing. In the group of patients with ST segment elevation during pacing, decrease in ejection fraction was associated with significant (P < 0.01) increase in midwall equatorial diastolic stress as compared with the patients with pacing-induced ST segment depression as

  19. Can Pacing Be Regulated by Post-Activation Potentiation? Insights from a Self-Paced 30 km Trial in Half-Marathon Runners

    Science.gov (United States)

    Del Rosso, Sebastián; Barros, Edilberto; Tonello, Laís; Oliveira-Silva, Iransé; Behm, David G.; Foster, Carl; Boullosa, Daniel A.

    2016-01-01

    Purpose Given the co-existence of post-activation potentiation (PAP) and fatigue within muscle, it is not known whether PAP could influence performance and pacing during distance running by moderating fatigue. The aim of this study was to assess the influence of PAP on pacing, jumping and other physiological measures during a self-paced 30 km trial. Methods Eleven male endurance-trained runners (half-marathon runners) volunteered to participate in this study. Runners participated in a multi-stage 30 km trial. Before the trial started, determination of baseline blood lactate (bLa) and countermovement jump (CMJ) height was performed. The self-paced 30 km trial consisted of 6 × 5 km splits. At the end of each 5 km split (60 s break), data on time to complete the split, CMJ height, Rating of Perceived Exertion (RPE) and blood lactate were collected while heart rate was continuously monitored. Results There was a significant decrease in speed (e.g. positive pacing strategy after the 4th split, p<0.05) with a progressive increase in RPE throughout the trial. Compared with baseline, CMJ height was significantly (p<0.05) greater than baseline and was maintained until the end of the trial with an increase after the 5th split, concomitant with a significant reduction in speed and an increase in RPE. Significant correlations were found between ΔCMJ and ΔSPEED (r = 0.77 to 0.87, p<0.05) at different time points as well as between RPE and speed (r = -0.61 to -0.82, p<0.05). Conclusion Our results indicates that fatigue and potentiation co-exist during long lasting endurance events, and that the observed increase in jump performance towards the end of the trial could be reflecting a greater potentiation potentially perhaps counteracting the effects of fatigue and preventing further reductions in speed. PMID:26934357

  20. Exercise performance in young patients with complete atrioventricular block: the relevance of synchronous atrioventricular pacing.

    Science.gov (United States)

    Gonzalez Corcia, M Cecilia; Remy, Lorraine Saint; Marchandise, Sebastien; Moniotte, Stephane

    2016-08-01

    At present, there are many pacing strategies for young patients with complete atrioventricular block. The most frequent policy is to attempt placing a dual-chamber system when possible; however, there is a group of patients that is functioning with a non-synchronous ventricular pacing, raising the question of the ideal timing to upgrade their systems. We investigated the exercise performance of a group of children and young adults with complete atrioventricular block and dual-chamber pacemakers in both single- and dual-chamber pacing modalities. A total of 15 patients performed maximal exercise stress testing after programming the VVIR or DDD modes with 2 hours of interval in a double-blind study protocol. Compared with VVIR pacing, DDD pacing resulted in increase in the peak VO2, longer test duration, major increase in the heart rate achieved during peak exercise, decreased systemic non-invasive arterial blood pressure measured at maximal exercise, higher maximal workload, prolongation of the anaerobic threshold timing, and better self-rated performance perception in all the patients. Synchronous atrioventricular pacing contributes to an increase in both the exercise performance and the performance perception in 100% of the patients. This difference contributes to create a sense of "fitness" with repercussions in the overall health, self-esteem, and life quality, as well as encourages youngster to practice sports. Our experience tends to favour upgrading patients' systems to dual-chamber systems before reaching the adolescent years, even if the centre policy is to prolong as long as possible the epicardial site in order to avoid long years of right ventricular pacing. PMID:26796814

  1. Plasma Aerodynamic Control Effectors for Improved Wind Turbine Performance

    Energy Technology Data Exchange (ETDEWEB)

    Mehul P. Patel; Srikanth Vasudevan; Robert C. Nelson; Thomas C. Corke

    2008-08-01

    Orbital Research Inc is developing an innovative Plasma Aerodynamic Control Effectors (PACE) technology for improved performance of wind turbines. The PACE system is aimed towards the design of "smart" rotor blades to enhance energy capture and reduce aerodynamic loading and noise using flow-control. The PACE system will provide ability to change aerodynamic loads and pitch distribution across the wind turbine blade without any moving surfaces. Additional benefits of the PACE system include reduced blade structure weight and complexity that should translate into a substantially reduced initial cost. During the Phase I program, the ORI-UND Team demonstrated (proof-of-concept) performance improvements on select rotor blade designs using PACE concepts. Control of both 2-D and 3-D flows were demonstrated. An analytical study was conducted to estimate control requirements for the PACE system to maintain control during wind gusts. Finally, independent laboratory experiments were conducted to identify promising dielectric materials for the plasma actuator, and to examine environmental effects (water and dust) on the plasma actuator operation. The proposed PACE system will be capable of capturing additional energy, and reducing aerodynamic loading and noise on wind turbines. Supplementary benefits from the PACE system include reduced blade structure weight and complexity that translates into reduced initial capital costs.

  2. Diritto internazionale umanitario, guerra e pace, diritti delle persone

    Directory of Open Access Journals (Sweden)

    Giovanni Barberini

    2011-11-01

    Full Text Available SOMMARIO: 1. Il diritto umanitario nei conflitti armati - 2. La codificazione del diritto umanitario - 3. Diritto della guerra e diritto della pace - 4. L’articolo 11 della costituzione italiana - 5. La protezione internazionale dei diritti e delle libertà della persona - 6. Conclusioni. Abstract: The military operators must also assure the peace with the weapons and, above all, the persons responsible of the operations must give test of great sensibility because busy to conjugate laws and rules war with the objectives of pacification. The authorities responsible for the operations at any time they need to know what they can or must do and what orders impart; they must know what it cannot do or what should be avoided. The international humanitarian law, important part of the international law, is constituted by conventional and consuetudinary norms that are applied in the relationships among States with a specific objective: to protect in time of armed conflict the people who do not take part or do not take more part in hostilities and impose bans or limits to the use of means offensive, of sophisticated weapons and methods of warfare in situations of armed conflict in act or to avoid sleepwalking. The codification of the international humanitarian law is initiated in the century XIX, above all when it was tried to introduce with the Declaration of Petersbourg in 1868 a principle that individualized in the contrariety to the laws of the humanity the impassable limit to respect in the armed conflicts. The codification has received then force and importance after the second world conflict that the consciences of the people had struck with the systematic practice of the most merciless violence making to record million of deads. The fundamental importance of the 1949 Geneva four Conventions is unanimously recognized. They are based on ratio of the existence and the responsibilities of the Organization of United Nations; they have properly

  3. Potential Effect of Physical Activity Calorie Equivalent (PACE Labeling on Adult Fast Food Ordering and Exercise.

    Directory of Open Access Journals (Sweden)

    Ray Antonelli

    Full Text Available Numeric calorie content labels show limited efficacy in reducing the number of calories ordered from fast food meals. Physical activity calorie equivalent (PACE labels are an alternative that may reduce the number of calories ordered in fast food meals while encouraging patrons to exercise.A total of 1000 adults from 47 US states were randomly assigned via internet survey to one of four generic fast food menus: no label, calories only, calories + minutes, or calories + miles necessary to walk to burn off the calories. After completing hypothetical orders participants were asked to rate the likelihood of calorie-only and PACE labels to influence (1 food choice and (2 physical activity.Respondents (n = 823 ordered a median of 1580 calories from the no-label menu, 1200 from the calories-only menu, 1140 from the calories + minutes menu, and 1210 from the calories + miles menu (p = 0.0001. 40% of respondents reported that PACE labels were "very likely" to influence food item choice vs. 28% for calorie-only labels (p<0.0001. 64% of participants reported that PACE labels were "somewhat likely" or "very likely" to influence their level of physical activity vs. 49% for calorie-only labels (p<0.0001.PACE labels may be helpful in reducing the number of calories ordered in fast food meals and may have the added benefit of encouraging exercise.

  4. Influence of filling on left ventricular diastolic pressure-volume curve during pacing ischemia in dogs.

    Science.gov (United States)

    Shintani, H; Glantz, S A

    1994-04-01

    The reversible upward shift of the diastolic pressure-volume curve that occurs during pacing-induced ischemia has not been fully explained by increases in passive chamber stiffness or reductions in relaxation rate. We measured the fully relaxed pressure-volume relation defined by both filling and nonfilling beats and the isovolumic relaxation time constant in nonfilling beats before and during demand ischemia using our in situ left ventricular volume clamping technique in 10 dogs. Pacing-induced ischemia shifted the diastolic pressure-volume curves in filling beats upward compared with the end-diastolic pressure-volume relation of the normally perfused heart. In contrast, the end-diastolic points for nonfilling beats during pacing-induced ischemia fell on the fully relaxed pressure-volume relation defined by the normally perfused heart. Left ventricular filling per se was necessary for the upward shift of the diastolic pressure-volume curve observed during pacing-induced ischemia. We speculate that active force developed during diastole induced by stretch activation or, perhaps, length-dependent changes in calcium sensitivity of the myofilaments in the ischemic myocardium due to stretch of the myocardium during rapid diastolic filling may contribute to the upward shift of the diastolic pressure-volume curve observed during pacing-induced ischemia. PMID:8184915

  5. High Frequency ELM Pacing by Lithium Pellet Injection on DIII-D

    Science.gov (United States)

    Bortolon, A.; Maingi, R.; Mansfield, D. K.; Nagy, A.; Roquemore, A. L.; Lunsford, R.; Jackson, G. L.; Osborne, T. H.; Parks, P. B.

    2015-11-01

    Full-shot, high-frequency pacing of edge localized modes (ELM) by lithium pellet injection has been demonstrated in DIII-D. A Lithium Granule Injector (LGI), recently installed on DIII-D to study pacing efficiency dependence on granule size and velocity, was tested in different ELMy scenarios (βN = 1.2-2.0) injecting granules of nominal diameter 0.3-0.9 mm, with injection speed 50-120 m/s and injection rates up to 500 Hz. Robust ELM pacing was documented on time windows up to 3.5 s, with triggering efficiency close to 100% obtained with 0.9 mm diameter granules, lower with smaller sizes and weakly dependent on granule velocity. Paced ELM frequencies up to 100 Hz were achieved, with a 2-5 fold increase over the natural ELM frequency and a consequent reduction of divertor peak heat flux. Overall, LGI high frequency pacing appeared to be compatible with high plasma performance, in terms of global confinement and pedestal characteristics. Work supported by the US Department of Energy under DE-AC02-09CH11466, DE-FC02-04ER54698.

  6. Indications for dual-chamber (DDD) pacing in implantable cardioverter-defibrillator patients.

    Science.gov (United States)

    Santini, M; Ansalone, G; Auriti, A; Magris, B; Pandozi, C; Altamura, G

    1996-09-12

    New technologic development of implantable cardioverter-defibrillators (ICDs) keeps up with the exponential increase of their use for primary and secondary prevention of sudden cardiac death. The first-generation ICD with limited shock capability alone could be considered adequate in most cardiac arrest victims, but it was not suitable for sudden death prevention in all high-risk patients with cardiac disease. The second-generation ICD was comprised of hybrid pacemaker-defibrillator systems that provided on-demand ventricular antibradycardia pacing. The third-generation devices include additional functions, such as antitachycardia pacing for ventricular tachycardia (VT) reversion and low-energy ventricular cardioversion, in addition to ventricular defibrillation and single-chamber ventricular demand pacing. In the near future, advanced dual-chamber atrioventricular (AV) pacing and defibrillating systems will also be available. The dual chamber ICD will allow atrial inhibited/dual-chamber (AAI/DDD) rate-responsive pacing, simultaneous atrial and ventricular sensing to optimize the arrhythmia identification, and ICD shock delivery in the proper arrhythmia-related chamber. Clinical benefits of these devices compared with their cost and complexity will require careful evaluation. PMID:8820847

  7. CATHENA/PACE calculations of aerosol transport in a simulated primary circuit

    International Nuclear Information System (INIS)

    Severe fuel damage in postulated loss-of-coolant accidents (LOCAs) in CANDU (Canada Deuterium Uranium) reactors may result in the release and transport of aerosol fission product materials from the fuel, through the primary circuit to containment and possibly into the atmosphere. In order to obtain a greater understanding of the mechanisms underlying fission product release, transport and deposition resulting from fuel damage in such accidents, a series of COG funded (Candu Owners Group) severe fuel damage experiments have been planned in the Blowdown Test Facility (BTF) at AECL Research, Chalk River. One of the planned experiments, BTF-104, has been simulated with the thermalhydraulics/aerosol transport code CATHENA/PACE, as a pretest investigation of fission product transport behaviour. Results of a number of CATHENA/PACE pretest simulations of the BTF-104 experiment are reported in this paper. The CATHENA code, developed at Whiteshell Laboratories, has been used to model the thermalhydraulic phenomena in a section of primary circuit piping representing the BTF. The PACE code (a Program for Aerosol Code Evaluation), also developed at Whiteshell, is coupled to the thermahydraulic calculations of CATHENA to model the transport of the aerosol fission products generated from the fuel. The PACE code contains aerosol physics models from a number of aerosol codes (e.g., HAA4, REMOVAL, NAUA, AEROSIM, etc.) and can therefore emulate any one of these by user selection. A number of codes (including VICTORIA, AEROSIM, REMOVAL, AND HAARM) were emulated with CATHENA/PACE for aerosol transport in this circuit

  8. Application of quantitative radioisotope angiocardiography (QRA) with transesophageal left atrium pacing for the assessment of the effect of sustained-release verapamil on left ventricular function

    International Nuclear Information System (INIS)

    The aim of the study was a comparative analysis of global and regional left ventricular function indices in patients with chronic coronary artery disease without myocardial infarction before and after one-month-long treatment with sustained-release verapamil (SR verapamil). The studies were performed in 20 patients with significant changes in coronarography. Left ventricular function was assessed by means of quantitative radioisotope angiocardiography (QRA) at rest, during, and directly after fast transoesophageal left atrium pacing. Before administration of the drug the left ventricular function parameters at rest were normal. At the peak and directly after the pacing the mean values decreased significantly of the global indices of ejection phase. SR verapamil at rest improved significantly the parameters of left ventricular filling phase but deteriorated the parameters of ejection phase. In conditions of transient myocardial ischaemia (during and directly after pacing) the drug decreased significantly the extent of reversible ischaemic left ventricular dysfunction. However, the regional indices of both cardiac cycle phases were not decreased during all stages of left ventricular function study in the patients before and after the treatment with SR verapamil

  9. Classifying running-related injuries based upon etiology, with emphasis on volume and pace

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Oestergaard; Nohr, Ellen Aagaard; Rasmussen, Sten;

    2013-01-01

    develop due to rapidly changing running volume, while others develop due to rapidly changing running pace. DESCRIPTION OF TOPIC WITH RELATED EVIDENCE: Evidence from clinical and experimental studies is presented to support the assertion that rapid change in running volume may lead to the development...... of patellofemoral pain syndrome, iliotibial band syndrome, and patellar tendinopathy, while change in running pace may be associated with the development of achilles tendinopathy, gastrocnemius injuries, and plantar fasciitis. DISCUSSIONRELATION TO CLINICAL PRACTICE: If this assertion is correct, bias may...... be prevented in future studies by categorizing injuries into volume or pacing injuries. However, more work is needed to provide further evidence in support of this approach. Future investigations of the link between training patterns and injury development should be designed as large-scale prospective studies...

  10. Progress report on case studies carried out within the United Nations Development Programme for Asian Co-operation on Energy and the Environment (PACE-E)

    International Nuclear Information System (INIS)

    The major goal of energy-environmental planning (EEP) in the framework of the Programme for Asian Co-operation on Energy and the Environment (PACE-E) is the enhancement of the environmental perspectives in energy planning and policy making in the developing countries of Asia. Three immediate objectives can be mentioned: (1) the strengthening of energy-environmental databases in Asia; (2) the development and application of innovative and effective energy impact assessment methodologies; and (3) the identification of suitable institutional structure that will result in a more transparent treatment of energy-environmental concerns in national energy plans and in subsectoral (e.g. coal, natural gas) development strategies. In the framework of Programme Element I, three sub-activities, to be executed by the Economic and Social Commission for Asia and the Pacific (ESCAP), have been proposed: the main objective of EEP1 is to strengthen the capacities of the methodologies of survey and sample design and the techniques of data processing. The main objective of EEP2 is to assist in the application of methods and tools of sectoral energy demand analysis and scenario building to evaluate energy conservation and fuel switching potentials. The EEP3 activities will consist of the review and application of methodologies and procedures for integrating environmental considerations into energy planning and policy analysis. The direct recipients of this programme will be policy makers, administrators and technicians from 20 Asian countries dealing with energy and environmental planning and management. The paper presents an overview of the implementation and first results of the various sub-activities of the EEP element of PACE-E executed by ESCAP and implemented by the Energy Planning Central Consultant Team of the Asian Institute of Technology. (author). 18 refs

  11. Gastric pacing for diabetic gastroparesis--does it work?

    LENUS (Irish Health Repository)

    Hannon, M J

    2011-05-01

    The management of diabetic gastroparesis resistant to medical therapy is very difficult Gastric electrical stimulation (GES) is a relatively new therapeutic modality which has shown some promise in international trials. It has seen use in four patients in Ireland. Our aim was to determine if GES improved patients\\' outcomes in terms of duration and cost of inpatient stay and glycaemic control. We reviewed the patients\\' case notes and calculated the number of days spent as an inpatient with symptomatic gastroparesis pre and post pacemaker, the total cost of these admissions, and patients\\' average HbA1c pre and post GES. Mean length of stay in the year pre GES was 81.75 days and 62.25 days in the year post GES (p=0.89). There was also no improvement in glycaemic control following GES. GES has been ineffective in improving length of inpatient stay and glycaemic control in our small patient cohort.

  12. Effects of ventricular pacing protocol on electrical restitution assessments in guinea-pig heart.

    Science.gov (United States)

    Osadchii, Oleg E

    2012-07-01

    The steep slope of the rate adaptation of ventricular action potential duration (APD) is thought to indicate profibrillatory tendency. In cardiac patients, APD restitution is commonly assessed by extrasystolic (S(1)-S(2)) stimulations rather than dynamic pacing, because the latter may provoke myocardial ischaemia. In this study, ventricular APD and effective refractory period (ERP) were measured in perfused guinea-pig hearts to determine whether S(1)-S(2) stimulations and dynamic pacing may have similar value in APD restitution assessments aimed to predict arrhythmic risk. The maximal restitution slope was greater upon S(1)-S(2) stimulation than dynamic pacing at the epicardium (S(1)-S(2), 1.2 ± 0.08; dynamic, 0.72 ± 0.06; P = 0.0004) and endocardium (S(1)-S(2), 1.45 ± 0.08; dynamic, 0.95 ± 0.06; P = 0.0003). This difference was partly accounted for by an effect of the previous pacing history, as evidenced by flattening of APD restitution upon reductions in the regular beating interval prior to S(2) application. Furthermore, shorter ERP than APD relationships enabled ventricular capture at shorter diastolic intervals during S(1)-S(2) stimulation than dynamic pacing at the epicardium (S(1)-S(2), -1 ± 3 ms; dynamic, 35 ± 3 ms; P early premature beats (diastolic interval of ∼0 ms), thereby flattening the S(1)-S(2) restitution curve, but had no effect on dynamic restitution. In hypokalaemia-induced arrhythmogenicity, a reduction in ventricular fibrillation threshold was paralleled by increased steepness of dynamic APD restitution, while no change in the maximal restitution slope was revealed by S(1)-S(2) stimulations. In summary, changes in electrical restitution obtained from extrasystolic stimulations may dissociate from those revealed by dynamic pacing. These findings therefore challenge the value of electrical restitution assessments based on extrasystolic stimulation alone, as commonly performed in the clinical setting. PMID:22447974

  13. [Influence of development pace on pharyngeal teeth formula in Abramis brama (L.) bream: experimental data].

    Science.gov (United States)

    Bolotovskii, A A; Levin, B A

    2011-01-01

    An experiment on acceleration and retardation of ontogenesis with thyroid manipulation has revealed direct changes in definitive dentition of pharyngeal bones in Abramis brama bream. As development pace accelerates, the number of teeth reduces to the formula 5-4. When development pace slows down, this number increases to the formula 6-5. Moreover, an additional minor row of teeth (1.6-5.1, 2.6-5.2) is formed. The observed changes transcend typical changes happening in nature. It is assumed that heterochronies provoke changes in the number of teeth. PMID:21786649

  14. MCTS self-paced training kit (exam 70-680) configuring Windows 7

    CERN Document Server

    McLean, Ian

    2010-01-01

    NOTE: The most recent printings of this title incorporate corrections to errors found in the earlier printings. This Self-Paced Training Kit is designed to help maximize your performance on 70-680, the required exam for the Microsoft® Certified Technology Specialist (MCTS): Windows 7, Configuration certification.This 2-in-1 kit includes the official Microsoft study guide, plus practice tests on CD to help you assess your skills. It comes packed with the tools and features exam candidates want most-including in-depth, self-paced training based on final exam content; rigorous, objective-by-obj

  15. Trame di Pace. Simboli, carte, azioni di un’utopia possibile. 1945-2003

    OpenAIRE

    Nadia Baiesi; Gianluca Gabrielli; Elda Guerra; Rossella Ropa

    2014-01-01

    La mostra racconta la storia degli uomini e delle donne che hanno ragionato di pace non più come di una nobile speranza, ma come dell’unica chance di salvezza per l’umanità. La scansione cronologica, per decenni, parte dal 1945 e arriva al 2003 con la diffusione della bandiera arcobaleno in occasione della campagna «Pace da tutti i balconi», nata per scongiurare il secondo conflitto in Iraq. Al centro della mostra un percorso sui simboli che sono stati in...

  16. Dual-Chamber Pacing for Cardiac Arrhythmias: Controversies in Cloning the Conduction System

    OpenAIRE

    Parsonnet, Victor; Bernstein, Alan D.; Norman, John C.

    1984-01-01

    From the outset, the art and science of cardiac pacing has been beset with a variety of problems. With the passage of time and concentrated effort in the interrelated sciences, many have been solved. We no longer are concerned with premature battery failure or leaking pulse-generator capsules, but now focus on an entirely new set of issues that beg for resolution. Foremost among these is the true role of dual-chamber pacing in the treatment of slow and fast cardiac arrhythmias of a multitude ...

  17. Pacing Lead-Induced Granuloma in the Atrium: A Foreign Body Reaction to Polyurethane

    Directory of Open Access Journals (Sweden)

    Shinagawa Yoko

    2013-01-01

    Full Text Available We described a case of an 82-year-old male who presented with a granuloma entrapping the polyurethane-coated pacing lead at the site of contact on the atrium. He had been paced for 8 years without symptoms or signs suggestive of an allergic reaction to the pacemaker system and died from thrombosis of the superior mesenteric artery and heart failure. A histological examination of the nodule showed an incidental granuloma with multinucleated giant cells. No granuloma was found in the heart or the lung.

  18. First Observation Of ELM Pacing With Vertical Jogs In A Spherical Torus

    Energy Technology Data Exchange (ETDEWEB)

    Gerhardt, S P; Canik, J M; Maingi, R; Bell, R; Gates, d; Goldston, R; Hawryluk, R; Le Blanc, B P; Menard, J; Sontag, A C; Sabbagh, S

    2010-07-15

    Experiments in a number of conventional aspect ratio tokamaks have been successful in pacing edge localized modes (ELMs) by rapid vertical jogging of the plasma. This paper demonstrates the first pacing of ELMs in a spherical torus plasma. Applied 30 Hz vertical jogs synchronized the ELMs with the upward motion of the plasma. 45 Hz jogs also lead to an increase in the ELM frequency, though the synchronization of the ELMs and jogs was unclear. A reduction in the ELM energy was observed at the higher driven ELM frequencies. __________________________________________________

  19. The effects of presentation pace and modality on learning a multimedia science lesson

    Science.gov (United States)

    Chung, Wen-Hung

    Working memory is a system that consists of multiple components. The visuospatial sketchpad is the main entrance for visual and spatial information, whereas acoustic and verbal information is processed in the phonological loop. The central executive works as a coordinator of information from these two subsystems. Numerous studies have shown that working memory has a very limited capacity. Based on these characteristics of working memory, theories such as cognitive load theory and the cognitive theory of multimedia learning provide multimedia design principles. One of these principles is that when verbal information accompanying pictures is presented in audio mode instead of visually, learning can be more effective than if both text and pictures are presented visually. This is called the modality effect. However, some studies have found that the modality effect does not occur in some situations. In most experiments examining the modality effect, the multimedia is presented as system-paced. If learners are able to repeat listening as many times as they need, the superiority of spoken text over visual text seems lessened. One aim of this study was to examine the modality effect in a learner-controlled condition. This study also used the one-word-at-a-time technique to investigate whether the modality effect would still occur if both reading and listening rates were equal. There were 182 college students recruited for this study. Participants were randomly assigned to seven groups: a self-paced listening group, a self-paced reading group, a self text-block reading group, a general-paced listening group, a general-paced reading group, a fast-paced listening group, and a fast-paced reading group. The experimental material was a cardiovascular multimedia module. A three-by-two between-subjects design was used to test the main effect. Results showed that modality effect was still present but not between the self-paced listening group and the self text-block reading group

  20. International piping benchmarks: use of the simplified code PACE 2. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, J.T.; Spence, J. (University of Strathclyde (United Kingdom)); Blundell, C. (Risley Nuclear Power Development Establishment, Central Technical Services, Risley, Warrington (United Kingdom)) (ed.)

    1979-05-15

    This report compares the results obtained using the code PACE 2 with the International Working Group on Fast Reactors (IWGFR) International Piping Benchmark solutions. PACE 2 is designed to analyse systems of pipework using a simplified method which is economical of computer time and hence inexpensive. This low cost is not achieved without some loss of accuracy in the solution, but for most parts of a system this inaccuracy is acceptable and those sections of particular importance may be reanalysed using more precise methods in order to produce a satisfactory analysis of the complete system at reasonable cost.

  1. The pace of past climate change vs. potential bird distributions and land use in the United States.

    Science.gov (United States)

    Bateman, Brooke L; Pidgeon, Anna M; Radeloff, Volker C; VanDerWal, Jeremy; Thogmartin, Wayne E; Vavrus, Stephen J; Heglund, Patricia J

    2016-03-01

    Climate change may drastically alter patterns of species distributions and richness, but predicting future species patterns in occurrence is challenging. Significant shifts in distributions have already been observed, and understanding these recent changes can improve our understanding of potential future changes. We assessed how past climate change affected potential breeding distributions for landbird species in the conterminous United States. We quantified the bioclimatic velocity of potential breeding distributions, that is, the pace and direction of change for each species' suitable climate space over the past 60 years. We found that potential breeding distributions for landbirds have shifted substantially with an average velocity of 1.27 km yr(-1) , about double the pace of prior distribution shift estimates across terrestrial systems globally (0.61 km yr(-1) ). The direction of shifts was not uniform. The majority of species' distributions shifted west, northwest, and north. Multidirectional shifts suggest that changes in climate conditions beyond mean temperature were influencing distributional changes. Indeed, precipitation variables that were proxies for extreme conditions were important variables across all models. There were winners and losers in terms of the area of distributions; many species experienced contractions along west and east distribution edges, and expansions along northern distribution edges. Changes were also reflected in the potential species richness, with some regions potentially gaining species (Midwest, East) and other areas potentially losing species (Southwest). However, the degree to which changes in potential breeding distributions are manifested in actual species richness depends on landcover. Areas that have become increasingly suitable for breeding birds due to changing climate are often those attractive to humans for agriculture and development. This suggests that many areas might have supported more breeding bird

  2. Effects of wind application on thermal perception and self-paced performance

    NARCIS (Netherlands)

    Teunissen, L.P.J.; Haan, A. de; Koning, J.J. de; Daanen, H.A.M.

    2013-01-01

    Physiological and perceptual effects of wind cooling are often intertwined and have scarcely been studied in self-paced exercise. Therefore, we aimed to investigate (1) the independent perceptual effect of wind cooling and its impact on performance and (2) the responses to temporary wind cooling dur

  3. Respiratory muscle pacing with chronically implanted intramuscular Permaloc electrodes: A feasibility study

    Directory of Open Access Journals (Sweden)

    James S. Walter, PhD

    2011-02-01

    Full Text Available We tested the feasibility of stimulating upper-intercostal and abdominal muscles plus the diaphragm by using chronically implanted intramuscular electrodes. During two survival surgeries with six dogs, intramuscular electrodes were implanted bilaterally in the three respiratory muscles. Standard stimulation of the diaphragm was conducted. The dorsolateral and ventrolateral abdominal wall areas were stimulated with a 25 mA current. The second to fourth intercostal spaces were stimulated to elicit the largest tidal volume associated with the least coactivation of the serratus and latissimus muscles. Lone diaphragm and upper-intercostal muscle pacing produced inhaled tidal volumes (mean +/- standard error of the mean of 293 +/- 36 mL and 59 +/- 17 mL, respectively. Lone abdominal muscle pacing produced an exhaled volume of 55 +/- 17 mL. Combined pacing of diaphragm and intercostal muscles increased the inhaled volume to 389 +/- 39 mL. The addition of abdominal pacing following the combined stimulation of diaphragm and intercostals increased the exhaled volume to 472 +/- 54 mL. During autopsy, dislodgement of the electrodes overlying the ribs was a concern and probably resulted from loose animal jackets. Chronic intramuscular Permaloc electrodes can be implanted in several respiratory muscles and increase tidal volumes more than diaphragm stimulation alone.

  4. Automated Apprenticeship Training (AAT). A Systematized Audio-Visual Approach to Self-Paced Job Training.

    Science.gov (United States)

    Pieper, William J.; And Others

    Two Automated Apprenticeship Training (AAT) courses were developed for Air Force Security Police Law Enforcement and Security specialists. The AAT was a systematized audio-visual approach to self-paced job training employing an easily operated teaching device. AAT courses were job specific and based on a behavioral task analysis of the two…

  5. Self-Paced Instruction in Biometry at the University of Texas School of Public Health.

    Science.gov (United States)

    Harrist, Ronald B.; And Others

    Among students of public health, there is a wide variation of aptitude, preparation, and motivation for the study of biometry. Self-paced instruction offers a way to deal with problems arising from such diversity. The Proctorial System of Instruction (PSI) as described by Keller was used to present two elementary biometry courses. Although there…

  6. Effect of heat and heat acclimatization on cycling time trial performance and pacing

    DEFF Research Database (Denmark)

    Racinais, Sebastien; Périard, Julien D; Karlsen, Anders;

    2015-01-01

    PURPOSE: To determine the effects of heat-acclimatization on performance and pacing during outdoor cycling time-trials (TT, 43.4km) in the heat. METHODS: Nine cyclists performed 3 TTs in hot ambient conditions (TTH, ∼37ºC) on the first (TTH-1), sixth (TTH-2) and fourteenth (TTH-3) days of training...

  7. The Effects of TV Program Pacing on the Behavior of Preschool Children

    Science.gov (United States)

    Anderson, Daniel R.; And Others

    1977-01-01

    Assertions that television (Sesame Street in particular) produces hyperactivity, impulsivity, disorganized behavior, and shortened attention spans in pre-school children were investigated. No evidence was found that rapid television pacing has an immediate negative impact on behavior of preschool children. (Author/STS)

  8. Molecular mechanisms of early atrial remodeling by rapid atrial pacing in rabbits

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To establish a rabbit atrial fibrillation model with rapid atrial pacing (RAP) and investigate its ultrastructural changes and expressions of L-type calcium channel subunits and potassium channel Ky4.3. Methods: Thirty-six rabbits were performed electrical stimulation through bipolar endocardial led by surgical technique, 600 beat per min from 0 to 48 h. Atrial ultrastructure was observed by transmission electron microscope (TEM) after different pacing times. mRNA were measured by reverse transcription-polymerase chain reaction (RT-PCR). Results: Atrial ultrastructure had alteration after 3 hours' pacing, such as mitochondria vacuolization, myofilament lysis and glucogen aggregation. The mRNA of the Ca2+ channel β1 and α1 subunits began to decrease after pacing of 6 h, which were paralleled with the change of Kv4.3 mRNA. But the auxiliary subunit α2 were not affected. Conclusion: Ultrastructural changes and mRNA levels of L-type calcium channel subunits and potassium channel Kv4.3 are decreased after RAP, with a mechanism of transcriptional down-regulation of underlying ion channels due to calcium overloading after RAP.

  9. Diagnostic accuracy of metronome-paced tachypnea to detect dynamic hyperinflation

    NARCIS (Netherlands)

    Lahaije, A.J.M.C.; Willems, L.M.; Hees, H.W. van; Dekhuijzen, P.N.R.; Helvoort, H.A.C. van; Heijdra, Y.F.

    2013-01-01

    INTRODUCTION: This prospective study was carried out to investigate if metronome-paced tachypnea (MPT) can serve as an accurate diagnostic tool to identify patients with chronic obstructive pulmonary disease (COPD) who are susceptible to develop dynamic hyperinflation during exercise. Commonly, this

  10. Self-Pacing a Gross Motor Skills Course: Crawler Tractor Operator, MOS 62E20.

    Science.gov (United States)

    Brennan, Mark F.; Taylor, John E.

    As part of the Army's emphasis on performance-oriented instruction in training centers, a study was conducted to determine the feasibility of using self-paced instruction in a gross motor skills course. The Crawler Tractor Operator Course, a seven-week heavy equipment course conducted at Fort Leonard Wood, Missouri was selected for the study…

  11. Cross-sectional Association between Walking Pace and Sleep-disordered Breathing.

    Science.gov (United States)

    Suri, S V; Batterham, A M; Ells, L; Danjoux, G; Atkinson, G

    2015-10-01

    Sleep-disordered breathing is an important comorbidity for several diseases, including stroke. Initial screening tools comprise simple yes/no questions about known risk factors for sleep-disordered breathing, e.g., obesity, sex. But walking speed has not been investigated in this context. We examined the cross-sectional association between walking pace and sleep-disordered breathing in the population-level Multi-Ethnic Study of Atherosclerosis. A sample of 2912 men and 3213 women (46-87 years) reported perceived walking pace outside their homes. A walking pacesleep apnoea (3.5%), self-reported apnoeas (8.4%), loud snoring (20.5%), daytime tiredness (22.2%) and slow-walking pace (26.9%). The 95% CI risk differences (multivariable-adjusted) for slow vs. faster walking pace were; sleep apnoea (0.4-2.5%), self-reported apnoeas (0.1-3.8%), loud snoring (1.2-8.3%), and daytime tiredness (3.0-7.8%). Risk differences were similar between sexes. The multivariable-adjusted risk ratio indicated that slower walkers had 1.5 (95% CI: 1.0 to 2.1) times the risk of sleep apnoea vs. faster walkers. In conclusion, a slower walking speed was associated with a greater prevalence of sleep-disordered breathing, independently from other common screening factors. Therefore, a simple walking speed question may help consolidate screening for this disorder. PMID:26090878

  12. Short Term Auditory Pacing Changes Dual Motor Task Coordination in Children with and without Dyslexia

    Science.gov (United States)

    Getchell, Nancy; Mackenzie, Samuel J.; Marmon, Adam R.

    2010-01-01

    This study examined the effect of short-term auditory pacing practice on dual motor task performance in children with and without dyslexia. Groups included dyslexic with Movement Assessment Battery for Children (MABC) scores greater than 15th percentile (D_HIGH, n = 18; mean age 9.89 [plus or minus] 2.0 years), dyslexic with MABC [less than or…

  13. Managing the Finances. PACE Revised. Level 2. Unit 16. Research & Development Series No. 240BB16.

    Science.gov (United States)

    Ashmore, M. Catherine; Pritz, Sandra G.

    This unit on managing the finances of a small business, the 16th in a series of 18 modules, is on the second level of the revised PACE (Program for Acquiring Competence in Entrepreneurship) comprehensive curriculum. Geared to advanced secondary and beginning postsecondary or adult students, the modules provide an opportunity to learn about and try…

  14. Increased diagnostic contribution of heart rate variability at 0.1Hz paced breathing

    Czech Academy of Sciences Publication Activity Database

    Jurák, Pavel; Halámek, Josef; Somers, V. K.; Nykodým, J.; Leinveber, P.; Fráňa, P.; Eisenberger, M.; Kára, T.

    2005-01-01

    Roč. 4, č. 1 (2005), s. 95. [World Congress on Heart Disease - New Trends in Research, Diagnosis and Treatment /12./. 16.07.2005-19.07.2005, Vancouver] R&D Projects: GA ČR(CZ) GA102/05/0402 Keywords : paced breathing * HRV * ICD Subject RIV: FS - Medical Facilities ; Equipment

  15. Investigating the Effects of Concurrent Performance of Physical and Cognitive Demanding Task in Paced Assembly Lines

    Directory of Open Access Journals (Sweden)

    Shakil Ahmed Shaikh

    2013-07-01

    Full Text Available The study was undertaken to investigate the effects of pacing on aspects of performance at an assembly task and on the operators' responses related to work behaviour, perceived workload and perceived stress. A particular objective of the study was to investigate whether physical and cognitive demands may interact in their influences on these effects. An assembly task was simulated in the laboratory and the level of pacing imposed, work height and memory load within the task were all varied. The results showed that the type of pacing commonly imposed (as is common with a lean manufacturing Takt time system in industry can significantly affect both performance and perceived workload and stress. Physical demands (through work height affecting posture and mental demand (through memory load were also found to have significant effects, as would be expected from the many studies of these in the literature. More importantly, some interactions were found between pacing and work height in their effects on quality of assembly and the operator's own rating of performance, and between work height and memory load in their effects on errors. These findings will need to be taken into account by companies when implementing Takt time systems.

  16. Modeling Pacing Behavior and Test Speededness Using Latent Growth Curve Models

    Science.gov (United States)

    Kahraman, Nilufer; Cuddy, Monica M.; Clauser, Brian E.

    2013-01-01

    This research explores the usefulness of latent growth curve modeling in the study of pacing behavior and test speededness. Examinee response times from a high-stakes, computerized examination, collected before and after the examination was subjected to a timing change, were analyzed using a series of latent growth curve models to detect…

  17. Managing after-work stress: paced breathing while watching video content (abstract)

    NARCIS (Netherlands)

    Tijs, T.J.W.; Weda, J.; Weffers-Albu, M.A.; Hoogenstraaten, W.

    2011-01-01

    Objectives. After a hard day’s work, we need to recover from work stress. Two frequently reported activities to relieve stress are television (TV) watching and paced breathing exercises. We investigated the potential of combining these techniques. Method. Two explorativeexperiments were conducted.

  18. Entrapment of a Pacing Lead within a Chiari Network: Utility of Intracardiac Echo and a Laser Sheath.

    Science.gov (United States)

    Aung, Htin; Espinosa, Raul E; Powell, Brian D; McLeod, Christopher J

    2016-06-01

    Although rare, Chiari networks are elaborate embryological remnants that can pose distinct challenges for catheter and pacing lead manipulation within the right atrium. Device entrapment may require open thoracotomy for removal, with significant morbidity. We report an unusual case of pacing lead entanglement within this structure, followed by prompt intracardiac echocardiographic identification and laser sheath removal. PMID:26873294

  19. Heart failure in patients with sick sinus syndrome treated with single lead atrial or dual-chamber pacing:

    DEFF Research Database (Denmark)

    Riahi, Sam; Nielsen, Jens Cosedis; Hjortshøj, Søren; Thomsen, Poul Erik B; Højberg, Søren; Møller, Mogens; Dalsgaard, Dorthe; Nielsen, Tonny; Asklund, Mogens; Friis, Elsebeth V; Christensen, Per Dahl; Simonsen, E. H.; Eriksen, Ulrik H; Jensen, G. V.; Svendsen, Jesper H; Toff, William D; Healey, Jeffrey S; Andersen, Henning R

    2012-01-01

    AIMS: Previous studies indicate that ventricular pacing may precipitate heart failure (HF). We investigated occurrence of HF during long-term follow-up among patients with sick sinus syndrome (SSS) randomized to AAIR or DDDR pacing. Furthermore, we investigated effects of percentage of ventricular...

  20. Ectopic jejunal pacemakers and gastric emptying after Roux gastrectomy: Effect of intestinal pacing

    International Nuclear Information System (INIS)

    The aims of this study were to determine whether ectopic pacemakers are present after meals in the Roux limbs of dogs after vagotomy and Roux gastrectomy, whether these pacemakers slow gastric emptying of liquids or solids, and whether abolishing the pacemakers with electric pacing might speed any slow emptying that occurs. In six dogs that underwent vagotomy and Roux gastrectomy and in four dogs that underwent vagotomy and Billroth gastrectomy (controls), myoelectric activity of the Roux limb or duodenum was measured during gastric emptying of a 500 kcal mixed meal of 99mTc-labeled cooked egg and 111In-labeled milk. Roux dogs were tested with and without pacing of the Roux limb. Roux dogs showed ectopic pacemaker in the Roux limb that drove the pacesetter potentials of the limb in a reverse, or orad, direction during 57% of the postprandial recordings. Billroth dogs had no ectopic pacemakers (p less than 0.05). Liquids emptied more slowly in Roux dogs (half-life (t1/2) = 121 +/- 15 minutes) than in Billroth dogs (t1/2 = 43 +/- 9 minutes; p less than 0.05), but solids emptied similarly in both groups of dogs (t1/2 approximately 8 hours). Pacing the Roux limb abolished the ectopic pacemakers, restored the slow emptying of liquids to the more rapid rate found in the Billroth dogs (t1/2: paced Roux, 72 +/- 15 minutes; Billroth, 43 +/- 9 minutes; p greater than 0.05) and did not change emptying of solids. The conclusion was that ectopic pacemakers present in the Roux limb after vagotomy and Roux gastrectomy drove the limb in a reverse direction and slowed emptying of liquids after the operation. The defect was corrected by pacing the Roux limb in a forward direction

  1. Effect of Peripheral Communication Pace on Attention Allocation in a Dual-Task Situation

    Science.gov (United States)

    Gueddana, Sofiane; Roussel, Nicolas

    Peripheral displays allow continuous awareness of information while performing other activities. Monitoring such a display while performing a central task has a cognitive cost that depends on its perceptual salience and the distraction it causes, i.e. the amount of attention it attracts away from the user’s primary action. This paper considers the particular case of peripheral displays for interpersonal communication. It reports on an experiment that studied the effect of peripheral communication pace on subjects’ allocation of attention in a dual-task situation: a snapshot-based peripheral monitoring task where participants need to assess the presence of a remote person, and a central text-correcting task against the clock. Our results show that the addition of the peripheral task caused a drop in the success rate of the central task. As the pace of snapshots increased, success rate decreased on the peripheral task while on the central one, success rate remained the same but failures to reply in time occurred more frequently. These results suggest that the increase in pace of snapshots caused participants to change their strategy for the central task and allocate more attention to the peripheral one, not enough to maintain peripheral performance but also not to the point where it would affect central performance. Overall, our work suggests that peripheral communication pace subtly influences attention allocation in dual-task situations. We conclude by discussing how control over information pace could help users of communication systems to adjust their local distraction as well as the attention they draw from remote users.

  2. Slow pace of dietary change in Scotland: 2001-9.

    Science.gov (United States)

    Wrieden, Wendy L; Armstrong, Julie; Sherriff, Andrea; Anderson, Annie S; Barton, Karen L

    2013-05-28

    Monitoring changes in the food and nutrient intake of a nation is important for informing the design and evaluation of policy. Surveys of household food consumption have been carried out annually in the UK since 1940 and, despite some changes over the years 1940-2000, the method used for the Expenditure and Food Survey (Living Costs and Food Survey from 2008) has been fundamentally the same since 2001. Using these surveys an analytical procedure was devised to compare food consumption and nutrient intake in Scotland with the Scottish dietary targets, and monitor change. This method takes into account contributions to composite foods and losses due to food preparation, as well as inedible and edible waste. There were few consistent improvements in consumption of foods or nutrients targeted for change over the period 2001-9. A significant but small increase was seen in mean fruit and vegetable consumption (259 g/d in 2001, 279 g/d in 2009, equating to an increase of less than 3 g/person per year). There was also a significant decrease in the percentage of food energy from SFA (15·5 % in 2001, 15·1 % in 2009) and from non-milk extrinsic sugars (15·5 % in 2001, 14·8 % in 2009), concurrent with a reduction in whole milk consumption and soft drink consumption, respectively. These small changes are encouraging, but highlight the time taken for even modest changes in diet to occur. To achieve a significant impact on the health of the present Scottish population, the improvements in diet will need to be greater and more rapid. PMID:23116795

  3. A Case Exemplar for National Policy Leadership: Expanding Program of All-Inclusive Care for the Elderly (PACE).

    Science.gov (United States)

    Cortes, Tara A; Sullivan-Marx, Eileen M

    2016-03-01

    In November 2015, President Obama signed the Program of All-Inclusive Care for the Elderly (PACE) Innovation Act, which expands a proven model of care to serve high-cost and high-need populations. Specifically, the law provides the Centers for Medicare & Medicaid Services with the authority to waive Medicaid requirements that could not be waived without additional statutory authority. Those requirements include the age of the beneficiary to be served and nursing home eligibility as a condition for PACE enrollment. The law also allows providers and other entities who are not current PACE providers the opportunity to become PACE providers and serve a predominately dually eligible population that has high needs and high cost through a coordinated, integrated model. The current article describes the impact of nursing on the legislation and policy that has shaped the evolution of the PACE program for more than 40 years. [Journal of Gerontological Nursing, 42(3), 9-14.]. PMID:26934968

  4. Latest news from the YETS: keeping up the pace

    CERN Multimedia

    Anaïs Schaeffer

    2016-01-01

    As we explained in the last edition of the Bulletin (see here), the winter technical stop (otherwise known as the YETS – Year-End Technical Stop) is setting a huge number of experts to work on all of the Laboratory’s accelerators. For the time being, the various maintenance and improvement activities are all on schedule.   Replacing the BHZ62 magnet at the PS Booster. (Photo: Sylvain Fumey.) At the PS Booster, the task of identifying obsolete cables is almost complete: around 2400 cables have been disconnected and are ready for removal, 400 more are still being analysed, and 66 turned out to still be in use, which underlines the importance of the identification work. Consolidation work is also going well and will soon be completed. Due to an unexpected leak in its vacuum chamber, the BHZ62 magnet has been replaced after 20 years of service. At the PS, a second cabling campaign has begun in the service tunnels, involving the installation of c...

  5. Brief time-based activity pacing instruction as a singular behavioral intervention was not effective in participants with symptomatic osteoarthritis.

    Science.gov (United States)

    Murphy, Susan L; Kratz, Anna L; Kidwell, Kelley; Lyden, Angela K; Geisser, Michael E; Williams, David A

    2016-07-01

    Osteoarthritis (OA) of the lower extremities is a prevalent cause of disability in which symptoms interfere with mobility and activity participation. Behavioral self-management for OA symptomatology is commonly recommended; but these interventions are underutilized, unstandardized in application, and at times, unavailable in the context of clinical care. For people with chronic pain, rehabilitation professionals may select to apply activity pacing instruction as one behavioral strategy to manage symptoms. Activity pacing is widely used in combination with other pharmacological and behavioral interventions but has not been studied as a singular behavioral intervention for people with OA. The purpose of this study was to evaluate the effectiveness of an occupational therapist-delivered, time-based activity pacing program for treatment of pain, fatigue, and physical function in people with symptomatic knee or hip OA. A 3-arm randomized controlled trial was conducted in which 193 people were randomized into tailored activity pacing, general activity pacing, or usual care arms. Assessments were done at 10 weeks and 6 months after baseline. Using linear mixed models, Western Ontario and McMaster Universities Osteoarthritis Index pain scores changed over time, decreasing the most in the general and usual care groups; only the usual care group had decreased pain over 6 months. The tailored and general activity pacing groups reported higher frequency of pacing behaviors than the usual care group at 10 weeks, but pacing was not sustained at 6 months. This trial does not support the use of time-based pacing as a singular behavioral strategy for people with knee or hip OA. PMID:26963847

  6. Leave-one-out prediction error of systolic arterial pressure time series under paced breathing

    CERN Document Server

    Ancona, N; Marinazzo, D; Nitti, L; Pellicoro, M; Pinna, G D; Stramaglia, S

    2004-01-01

    In this paper we show that different physiological states and pathological conditions may be characterized in terms of predictability of time series signals from the underlying biological system. In particular we consider systolic arterial pressure time series from healthy subjects and Chronic Heart Failure patients, undergoing paced respiration. We model time series by the regularized least squares approach and quantify predictability by the leave-one-out error. We find that the entrainment mechanism connected to paced breath, that renders the arterial blood pressure signal more regular, thus more predictable, is less effective in patients, and this effect correlates with the seriousness of the heart failure. The leave-one-out error separates controls from patients and, when all orders of nonlinearity are taken into account, alive patients from patients for which cardiac death occurred.

  7. IN VIVO CHARACTERIZATION OF ATTACHMENT SAFETY BETWEEN CARDIAC PACING LEAD AND CANINE HEART MUSCLE

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In vivo experiments of screwing the electrode of canine hearts and assigning external excitation on the lead-myocardium interface was carried out to evaluate the lead/myocardium adherence safety. The electrode is specially designed to host a measurement unit of strain gauges.We obtained the lead/heart interactions data from 12 dogs under natural heart beating and beating with external excitations. The data recorded from the acute phase and the chronic phase of pulling out pacing leads were compared with each other. The electrode/heart interaction is caused by the heart beat and influenced by the lung breath. This process induced tolerable damage to the lead or myocardium. The interaction decreases as the frequency of external excitations increases. The lead is more likely to be detached from myocardium under higher excitation frequency. At the same implanting sites, safer pacing lead/myocardium attachment can be realized in the chronic tests than in the acute tests.

  8. Dynamic exploration of myocardial perfusion by coronary blood flow radioisotopic measurement during auricular pacing

    International Nuclear Information System (INIS)

    Reproducibility of the radiocardiographic method using 42 Potassium has been verified. Coronary blood flow has so been measured in 50 control subjects and coronary heart disease patients, at steady state and during auricular pacing at 150 beats per minute. In control subjects group, under auricular pacing coronary blood flow increases by a mean value of 15%; on the other hand it decreases by a mean value of 32% in coronary heart disease patients bearing obvious coronarography lesions. The cardiac output coronary fraction increases by a mean value of 27% in the control subjects group; it remains unchanged in coronary heart disease patients. On the contrary this coronary fraction increases in a significant way after functional aortocoronary bypass

  9. Trame di Pace. Simboli, carte, azioni di un’utopia possibile. 1945-2003

    Directory of Open Access Journals (Sweden)

    Nadia Baiesi

    2014-06-01

    Full Text Available La mostra racconta la storia degli uomini e delle donne che hanno ragionato di pace non più come di una nobile speranza, ma come dell’unica chance di salvezza per l’umanità. La scansione cronologica, per decenni, parte dal 1945 e arriva al 2003 con la diffusione della bandiera arcobaleno in occasione della campagna «Pace da tutti i balconi», nata per scongiurare il secondo conflitto in Iraq. Al centro della mostra un percorso sui simboli che sono stati inventati, ripresi, risignificati in diversi contesti, movimenti radicali del pacifismo antimilitarista e nonviolento e movimenti contro singole guerre. Accompagnano i materiali iconografici (bandiere e manifesti originali, opere d’arte del maestro Anastasi, due percorsi documentari con immagini d’epoca, locandine, testi di decreti, opuscoli, volantini, articoli di quotidiani e riviste.

  10. Self-Paced E-Training in E-Learning for University Teaching Staff

    Directory of Open Access Journals (Sweden)

    Norah Ahmed Al-Malki

    2015-03-01

    Full Text Available The shift towards adopting e-training methods and practices in the workplace to equip staff with soft and hard skills have become an essential component of training in many Higher Education institutions. The aim of this paper is to advocate such a shift in Saudi universities through presenting the preliminary outcomes of a short-scale pilot study conducted by the Deanship of E-learning and Distance Education (DELDE during August 2014. Basically, the paper introduces the results of a first run of a self-paced e-training program focusing on introducing topics related to e-learning development and instruction. The paper 1 explores the pedagogical motivation for adopting the self-paced learning model, 2 outlines the elements of the developed course, and 3 discusses the results of the first run of the e-training program.

  11. Pacing, packing and sex-based differences in Olympic and IAAF World Championship marathons.

    Science.gov (United States)

    Hanley, Brian

    2016-09-01

    The aim of this study was to describe pacing profiles and packing behaviours of athletes in Olympic and World Championship marathons. Finishing and split times were collated for 673 men and 549 women across nine competitions. The mean speeds for each intermediate 5 km and end 2.2 km segments were calculated. Medallists of both sexes maintained even-paced running from 10 km onwards whereas slower finishers dropped off the lead pack at approximately half-distance. Athletes who ran with the same opponents throughout slowed the least in the second half (P sex-based differences in tactics adopted and design training programmes accordingly. PMID:26736042

  12. BET 2: Diagnosing acute myocardial infarction in the presence of ventricular pacing: can Sgarbossa criteria help?

    Science.gov (United States)

    Jothieswaran, Arunan; Body, Richard

    2016-09-01

    The Sgarbossa criteria can be used to identify patients who have acute myocardial infarction (AMI) in the presence of left bundle branch block, which obscures the usual changes associated with ST elevation myocardial infarction. Patients with ventricular paced rhythm have ECG changes with similar morphology to left bundle branch block. A short-cut systematic review was carried out to establish whether the Sgarbossa criteria can accurately diagnose AMI in the presence of ventricular paced rhythm. Three studies were directly relevant to the question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The clinical bottom line is that. PMID:27539980

  13. Interaction Equivalency in Self-Paced Online Learning Environments: An Exploration of Learner Preferences

    Directory of Open Access Journals (Sweden)

    Jason F. Rhode

    2009-02-01

    Full Text Available This mixed methods study explored the dynamics of interaction within a self-paced online learning environment. It used rich media and a mix of traditional and emerging asynchronous computer-mediated communication tools to determine what forms of interaction learners in a self-paced online course value most and what impact they perceive interaction to have on their overall learning experience. This study demonstrated that depending on the specific circumstance, not all forms of interaction may be either equally valued by learners or effective. Participants differentiated among the various learning interactions available and indicated that informal interactions were as important as formal interactions in determining the quality of the online learning experience. Participants also reported the activity of blogging as being equally valued and in some ways superior to instructor-directed asynchronous discussion via the discussion board in a learning management system.

  14. Effect of deceptively aggressive bike pacing on sprint-distance triathlon performance and associated perceptual responses

    OpenAIRE

    Taylor, Danny; Smith, Mark F.

    2015-01-01

    INTRODUCTION: Cycling at the highest sustainable intensity (i.e. isolated time-trial power output) is suggested as the best strategy to optimise sprint-distance triathlon performance (Suriano & Bishop, 2010, Eur J Appl Physiol, 110, 4:753-760). However, it is unclear how expectations, beliefs and perceptions influence the effectiveness of aggressive mid-event pacing during multi-modal endurance events. Taylor & Smith (2014, Physiol Behav, 133:45-52) suggest meaningful changes in triathlon per...

  15. Effect of deceptively aggressive bike pacing on sprint-distance triathlon performance

    OpenAIRE

    Taylor, Daniel; Smith, Mark F.

    2015-01-01

    Introduction: Whilst aggressive bike pacing has been found to impair subsequent run performance during triathlon, this strategy appears to enhance total cycle-run time over the sprint-distance format (Suriano & Bishop, 2010). As such, cycling at the highest sustainable intensity (i.e. isolated TT power output) is suggested as the best strategy to optimise overall performance time in the event. However, it is unclear how an athlete’s expectations, beliefs and perceptions influence the effectiv...

  16. Managing after-work stress: paced breathing while watching video content (abstract)

    OpenAIRE

    Tijs, T.J.W.; Weda, J.; Weffers-Albu, M.A.; Hoogenstraaten, W.

    2011-01-01

    Objectives. After a hard day’s work, we need to recover from work stress. Two frequently reported activities to relieve stress are television (TV) watching and paced breathing exercises. We investigated the potential of combining these techniques. Method. Two explorativeexperiments were conducted. In both experiments, stress was measured through physiological monitoring (heart rate, blood pressure, skinconductance, peripheral temperature, and respiration) and the Stress Arousal Checklist [3]....

  17. Reading sentences in Serbian: Effects of alphabet and reading mode in self-paced reading task

    OpenAIRE

    Vejnović Dušan; Jovanović Tamara

    2012-01-01

    The study examined the influence of alphabet (Cyrillic vs. Latin) and reading mode (silent reading vs. reading aloud) on sentence reading speed in Serbian. Entire-sentence and single-word reading times were obtained from the moving window paradigm in the self-paced sentence reading task. Sentences printed in Latin took less time for reading than sentences printed in Cyrillic and silent reading was more rapid than reading aloud. Single-word processing results followed the pattern observe...

  18. Response of atrial flutter to overdrive atrial pacing and intravenous disopyramide phosphate, singly and in combination.

    OpenAIRE

    Camm, J; Ward, D.; Spurrell, R

    1980-01-01

    Ten patients who suffered spontaneous paroxysms of atrial flutter were investigated by electrophysiological techniques. Two had overt Wolff-Parkinson-White syndrome; three Lown-Ganong-Levine syndrome; and one a concealed accessory atrioventricular connection. Atrial flutter was initiated, at study, by right atrial pacing and electrograms from the right atrium and coronary sinus were observed for at least five minutes to ensure stable flutter in both atria. Atrial flutter was terminated by 2.5...

  19. Hemodynamic Surveillance of Ventricular Pacing Effectiveness with the Transvalvular Impedance Sensor

    OpenAIRE

    Valeria Calvi; Giovanni Pizzimenti; Marco Lisi; Giuseppe Doria; Ludovico Vasquez; Francesco Lisi; Salvatore Felis; Donatella Tempio; Alfredo Virgilio; Alberto Barbetta; Franco Di Gregorio

    2014-01-01

    The Transvalvular Impedance (TVI) is derived between atrial and ventricular pacing electrodes. A sharp TVI increase in systole is an ejection marker, allowing the hemodynamic surveillance of ventricular stimulation effectiveness in pacemaker patients. At routine follow-up checks, the ventricular threshold test was managed by the stimulator with the supervision of a physician, who monitored the surface ECG. When the energy scan resulted in capture loss, the TVI system must detect the failure a...

  20. Explaining the Slow Pace of Energy Technological Innovation: Why Market Conditions Matter

    OpenAIRE

    Jin, Wei; Zhang, ZhongXiang

    2014-01-01

    As a useful complement to numerous innovation policy studies from a normative perspective, this paper provides a positive framework to analyze the basic economic mechanism of energy technological innovation and explains its slow pace of technological progress. We find that the capital-intensiveness of energy technology is an inhibiting factor to catalyze market size effect and slows innovations and diffusions of energy technology in the market. We also show that the substantial homogeneity of...

  1. Predicting Number of Zombies in DDoS Attacks Using Pace Regression Model

    OpenAIRE

    Gupta, B. B.

    2012-01-01

    A DDoS attacker attempts to disrupt a target, by flooding it with illegitimate packets which are generated from a large number of zombies, usurping its bandwidth and overtaxing it to prevent legitimate inquiries from getting through. This paper reports the evaluation results of proposed approach that is used to predict number of zombies using Pace Regression Model. A relationship is established between number of zombies and observed deviation in sample entropy. Various statistical performance...

  2. Self-directed/self-paced learning using course templates and community modules

    OpenAIRE

    Tannant, Maria

    2014-01-01

    With UCA based across 5 campuses and 2 learning technologists to manage the university's Virtual Learning Environment (VLE), this presentation offers a window into how they have developed a mechanism and collection of self-directed/self-paced learning resources for both students and faculty staff. These learning resources are applied to the course templates at the start of each academic year. Template content for students include: Digital literacy skills, professional networking, buil...

  3. The impact of the perception of rhythmic music on self-paced oscillatory movements.

    Science.gov (United States)

    Peckel, Mathieu; Pozzo, Thierry; Bigand, Emmanuel

    2014-01-01

    Inspired by theories of perception-action coupling and embodied music cognition, we investigated how rhythmic music perception impacts self-paced oscillatory movements. In a pilot study, we examined the kinematic parameters of self-paced oscillatory movements, walking and finger tapping using optical motion capture. In accordance with biomechanical constraints accounts of motion, we found that movements followed a hierarchical organization depending on the proximal/distal characteristic of the limb used. Based on these findings, we were interested in knowing how and when the perception of rhythmic music could resonate with the motor system in the context of these constrained oscillatory movements. In order to test this, we conducted an experiment where participants performed four different effector-specific movements (lower leg, whole arm and forearm oscillation and finger tapping) while rhythmic music was playing in the background. Musical stimuli consisted of computer-generated MIDI musical pieces with a 4/4 metrical structure. The musical tempo of each song increased from 60 BPM to 120 BPM by 6 BPM increments. A specific tempo was maintained for 20 s before a 2 s transition to the higher tempo. The task of the participant was to maintain a comfortable pace for the four movements (self-paced) while not paying attention to the music. No instruction on whether to synchronize with the music was given. Results showed that participants were distinctively influenced by the background music depending on the movement used with the tapping task being consistently the most influenced. Furthermore, eight strategies put in place by participants to cope with the task were unveiled. Despite not instructed to do so, participants also occasionally synchronized with music. Results are discussed in terms of the link between perception and action (i.e., motor/perceptual resonance). In general, our results give support to the notion that rhythmic music is processed in a motoric

  4. The impact of the perception of rhythmic music on oscillatory self-paced movements

    Directory of Open Access Journals (Sweden)

    Mathieu ePeckel

    2014-09-01

    Full Text Available Inspired by theories of perception-action coupling and embodied music cognition, we investigated how rhythmic music perception impacts self-paced oscillatory movements. In a pilot study, we examined the kinematic parameters of self-paced oscillatory movements, walking and finger tapping using optical motion capture. In accordance with biomechanical constraints accounts of motion, we found that movements followed a hierarchical organization depending on the proximal/distal characteristic of the limb used. Based on these findings, we were interested in knowing how and when the perception of rhythmic music could resonate with the motor system in the context of these constrained oscillatory movements. In order to test this, we conducted an experiment where participants performed four different effector-specific movements (lower leg, whole arm and forearm oscillation and finger tapping while rhythmic music was playing in the background. Musical stimuli consisted of computer-generated MIDI musical pieces with a 4/4 metrical structure. The musical tempo of each song increased from 60 BPM to 120 BPM by 6 BPM increments. A specific tempo was maintained for 20s before a 2s transition to the higher tempo. The task of the participant was to maintain a comfortable pace for the four movements (self-paced while not paying attention to the music. No instruction on whether to synchronize with the music was given. Results showed that participants were distinctively influenced by the background music depending on the movement used with the tapping task being consistently the most influenced. Furthermore, eight strategies put in place by participants to cope with task were unveiled. Despite not instructed to do so, participants also occasionally synchronized with music. Results are discussed in terms of the link between perception and action (i.e. motor/perceptual resonance. In general, our results give support to the notion that rhythmic music is processed in a

  5. Social marketing of a different pace: between liberal and paternalistic management of social change:

    OpenAIRE

    Kamin, Tanja

    2011-01-01

    This article examines social marketing as one of the approaches for managing social change. We place the concept of social marketing on the continuum between liberal and paternalistic approaches to social change management. Furthermore, we consider which forms of social change management in Slovenia are dominant, and in which position among them is social marketing. The presumption of the discussion is that social marketing has developed at different paces and with different acknowledgements ...

  6. Potential Effect of Physical Activity Calorie Equivalent (PACE) Labeling on Adult Fast Food Ordering and Exercise

    OpenAIRE

    Ray Antonelli; Viera, Anthony J.

    2015-01-01

    Introduction Numeric calorie content labels show limited efficacy in reducing the number of calories ordered from fast food meals. Physical activity calorie equivalent (PACE) labels are an alternative that may reduce the number of calories ordered in fast food meals while encouraging patrons to exercise. Methods A total of 1000 adults from 47 US states were randomly assigned via internet survey to one of four generic fast food menus: no label, calories only, calories + minutes, or calories + ...

  7. The pace of MNEs’ sequential entries: Cumulative entry experience and the dynamic process

    OpenAIRE

    Gerald Yong Gao; Yigang Pan

    2010-01-01

    This study examines the pace with which multinational enterprises undertake sequential entries in a foreign market. We focus on learning effects from cumulative entry experience of different modes within a host market. Moreover, we investigate the dynamic process of entry mode switch, and how cumulative entry experience reduces the expansion constraint. Using a dataset of sequential entries by US firms in China during 1979–2002, we find that the impact of cumulative entry experience on the pa...

  8. Preoperative evaluation of cardiac risk by means of atrial pacing and thallium 201 scintigraphy

    International Nuclear Information System (INIS)

    Atrial pacing and thallium 201 scintigraphy were done in 61 patients with known or suspected coronary artery disease referred for evaluation of cardiac risk before elective vascular surgery. All patients had noncardiac limitations precluding performance of an adequate exercise stress test. Before atrial pacing all were considered to be at low risk of a postoperative cardiac event based on assessment of clinical parameters. Vascular surgery was subsequently performed in 47 patients. In these patients, pacing-induced ST segment depression greater than or equal to 1 mm occurred in 18, a fixed perfusion defect occurred in 11, and a reversible defect occurred in six. Two of the six patients with reversible perfusion defects had preoperative coronary angiography; both had significant coronary artery disease (one or more lesions greater than or equal to 50%). Two patients (one of whom had a reversible perfusion defect) underwent preoperative coronary revascularization and tolerated subsequent vascular surgery well. All other patients received only medical therapy. None of the 47 patients undergoing vascular surgery had a postoperative cardiac event (unstable angina, congestive heart failure, myocardial infarction, or cardiac death). Of the 14 patients in whom vascular surgery was deferred or canceled, surgery was canceled for noncardiac reasons in seven. Six of these seven patients had a normal perfusion scan; none had a reversible perfusion defect or marked (greater than or equal to 2 mm) ST segment depression. No cardiac event occurred during a 3-month period after atrial pacing in any of these patients. Six of the remaining seven patients had reversible perfusion defects

  9. Differential effects of prolonged work on performance measures in self-paced speed tests.

    OpenAIRE

    Steinborn, Michael B.; HAGEN C. FLEHMIG; Westhoff, Karl; Langner, Robert

    2010-01-01

    Time-related changes in the speeded performance of complex cognitive tasks are considered to arise from the combined effects of practice and mental fatigue. Here we explored the differential contributions of practice and fatigue to performance changes in a self-paced speeded mental addition and comparison task of about 50 min duration, administered twice within one week’s time. Performance measures included average response speed, accuracy, and response speed variability. The results revealed...

  10. TREATMENT PLANNING, PACING, AND COUNTERTRANSFERENCE: PERSPECTIVES ON THE PSYCHOTHERAPY OF EARLY AFFECT-CONFUSION

    Directory of Open Access Journals (Sweden)

    Richard G. Erskine

    2012-12-01

    Full Text Available This article is a rejoinder and elaboration on the article “Early Affect-Confusion: The ‘Borderline’ Between Despair and Rage: Part 1 of a Case Study Trilogy” and addresses the distinction between personality style, pattern, and disorder. It describes the pacing of a time-limited psychotherapy, the use of phenomenological inquiry in resolving transferential enactments, and the psychological function of idealization.

  11. RETARDATION OF PACE OF LIFE AND RESOURCES TRANSFORMATION – SOME IMPLICATIONS OF CITIZENS

    OpenAIRE

    Joanna Kostecka

    2014-01-01

    The article attempts to explain the term retardation of pace of life and transforming natural resources, highlights the complexity of the concept and presents proposals for action for its dissemination. Retardation of resources transformation is an important tool for the implementation of the new approach on those environmental resources and services that are left. Environmental education that supports the implementation of retardation should use active methods of education and should be inte...

  12. Induction of atrial fibrillation with rapid high voltage ventricular pacing for ventricular fibrillation conversion testing

    OpenAIRE

    Schuchert, A; Kuhl, M; Ruppel, R; Meinertz, T

    2000-01-01

    OBJECTIVE—To assess whether rapid high voltage ventricular pacing can also induce atrial fibrillation, and whether the induction of atrial fibrillation during ventricular fibrillation conversion testing is related to the patient's heart disease.
DESIGN—Prospective study of 50 patients who received the dual chamber implantable cardioverter-defibrillator (ICD) Ventak AV II DR (Guidant) as a first implant. This device can record atrial activity even during a ventricular fibrillation episode and ...

  13. PACE: Pattern Accurate Computationally Efficient Bootstrapping for Timely Discovery of Cyber-Security Concepts

    OpenAIRE

    McNeil, Nikki; Bridges, Robert A.; Iannacone, Michael D.; Czejdo, Bogdan; Perez, Nicolas; Goodall, John R.

    2013-01-01

    Public disclosure of important security information, such as knowledge of vulnerabilities or exploits, often occurs in blogs, tweets, mailing lists, and other online sources months before proper classification into structured databases. In order to facilitate timely discovery of such knowledge, we propose a novel semi-supervised learning algorithm, PACE, for identifying and classifying relevant entities in text sources. The main contribution of this paper is an enhancement of the traditional ...

  14. Evaluation of a New Mixed-Phase Cloud Microphysics Parameterization with a Single Column Model, CAPT Forecasts and M-PACE Observations

    Science.gov (United States)

    Liu, X.; Xie, S.; Boyle, J.; Klein, S.; Ghan, S.

    2007-12-01

    Most global climate models generally prescribe the partitioning of condensed water into liquid droplets and ice crystals in mixed-phase clouds according to a temperature-dependent function, which affects modeled cloud phase, cloud lifetime and radiative properties. In this study we evaluate a new mixed-phase cloud microphysics parameterization (for ice nucleation and water vapor deposition) against the Atmospheric Radiation Measurement (ARM) Mixed-phase Arctic Cloud Experiment (M-PACE) observations using the NCAR Community Atmospheric Model Version 3 (CAM3) running in the single column mode (SCAM) and in the CCPP-ARM Parameterization Testbed (CAPT) forecasts. It is found that SCAM with the new physically-based cloud microphysical scheme produces a more realistic simulation of the cloud phase structure and the partitioning of condensed water into liquid droplets against observations during the M-PACE than the standard CAM with an oversimplified cloud microphysics. CAM3 in the CAPT forecasts significantly underestimates the observed boundary layer mixed- phase cloud fraction. The simulation of the boundary layer mixed-phase clouds and their microphysical properties is considerably improved in CAM3 when the new scheme is used. The new scheme also leads to an improved simulation of the surface and top of the atmosphere longwave radiative fluxes. Both SCAM simulations and CAPT forecasts suggest that the ice number concentration could play an important role in the simulated mixed-phase cloud microphysics, and thereby needs to be realistically represented in global climate models.

  15. Migration of a retained temporary epicardial pacing wire into an abdominal aortic aneurysm.

    Science.gov (United States)

    Mukaihara, Kosuke; Yotsumoto, Goichi; Matsumoto, Kazuhisa; Imoto, Yutaka

    2015-07-01

    A 69-year old male was referred to our hospital for the treatment of coronary artery disease. Preoperative computed tomography (CT) revealed an abdominal aortic aneurysm (AAA) and a giant tumour of the left kidney. He underwent off-pump coronary artery bypass grafting (OPCAB) prior to aneurysmectomy and nephrectomy. Temporary epicardial pacing wires (TEPWs) were placed on the right atrium and right ventricle. The bipolar ventricular wire was removed and the unipolar atrial wire was cut flush with the skin surface on postoperative day 5. CT 7 days after the OPCAB procedure revealed a retained TEPW sutured to the right atrial wall. One month later, the patient underwent a repair of the AAA and left nephrectomy. We found that a TEPW had migrated inside the AAA intraoperatively. The retained TEPW was thus no longer observed on postoperative CT. Migration of the atrial pacing wire through the aortic lumen was suspected, although the detailed mechanism is unknown. This is the first reported case of a migrated temporary pacing wire into the aorta under noninfectious conditions. PMID:25173602

  16. The influence of performance level, age and gender on pacing strategy during a 100-km ultramarathon.

    Science.gov (United States)

    Renfree, Andrew; Crivoi do Carmo, Everton; Martin, Louise

    2016-01-01

    The aim of this study is to analyse the influence of performance level, age and gender on pacing during a 100-km ultramarathon. Results of a 100-km race incorporating the World Masters Championships were used to identify differences in relative speeds in each 10-km segment between participants finishing in the first, second, third and fourth quartiles of overall positions (Groups 1, 2, 3 and 4, respectively). Similar analyses were performed between the top and bottom 50% of finishers in each age category, as well as within male and female categories. Pacing varied between athletes achieving different absolute performance levels. Group 1 ran at significantly lower relative speeds than all other groups in the first three 10-km segments (all P bottom' competitors in the early stages, but higher relative speeds in the later stages. Females showed lower relative starting speeds and higher finishing speeds than males. 'Top' and 'bottom' finishing males displayed differing strategies, but this was not the case within females. Although pacing remained consistent across age categories, it differed with level of performance within each, possibly suggesting strategies are anchored on direct competitors. Strategy differs between genders and differs depending on performance level achieved in males but not females. PMID:26034882

  17. A positron emission tomography study of self-paced finger movements at different frequencies

    International Nuclear Information System (INIS)

    Regional cerebral blood flow was measured in six right-handed volunteers using positron emission tomography during tasks involving repetitive self-paced finger tapping at five different frequencies. The contralateral primary sensorimotor cortex, the pre-supplementary motor area and the cingulate motor area showed significant activation during self-paced finger tapping tasks, compared with the resting state. A positive correlation between the regional cerebral blood flow and the movement frequency was found only in the primary sensorimotor cortex. In the pre-supplementary motor area and the cingulate motor area, however, activity increased when the subject employed movement frequencies faster or slower than his own pace. The same tendency was noted with respect to the relative variability of the inter-tapping interval.The results therefore indicate that the activity of the pre-supplementary motor area and the cingulate motor area may well be related to the increased difficulty in motor control rather than to the execution of the movement itself. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  18. Gradual Pace

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    China pledges to promote steady development of its financial sector and prevent possible risks pointed out by the IMF The People’s Bank of China,the central bank,recently responded to a report-Financial Sector Assessment for China-jointly issued by the International Monetary Fund(IMF) and the

  19. Keeping Pace

    Science.gov (United States)

    Scully, Maura King

    2012-01-01

    So many communications channels, so little time and, usually, so few resources is the situation today's communicators face. Educational institutions, places steeped in history and tradition, "have been slow to react." But while the communications channels have changed, the fundamentals of communication haven't. Maintaining perspective about…

  20. The size and structure of arm movement variability decreased with work pace in a standardised repetitive precision task.

    Science.gov (United States)

    Srinivasan, Divya; Samani, Afshin; Mathiassen, Svend Erik; Madeleine, Pascal

    2015-01-01

    Increased movement variability has been suggested to reduce the risk of developing musculoskeletal disorders caused by repetitive work. This study investigated the effects of work pace on arm movement variability in a standardised repetitive pipetting task performed by 35 healthy women. During pipetting at slow and fast paces differing by 15%, movements of arm, hand and pipette were tracked in 3D, and used to derive shoulder and elbow joint angles. The size of cycle-to-cycle motor variability was quantified using standard deviations of several kinematics properties, while the structure of variability was quantified using indices of sample entropy and recurrence quantification analysis. When pace increased, both the size and structure of motor variability in the shoulder and elbow decreased. These results suggest that motor variability drops when repetitive movements are performed at increased paces, which may in the long run lead to undesirable outcomes such as muscle fatigue or overuse. PMID:25216404

  1. PACE4-Based Molecular Targeting of Prostate Cancer Using an Engineered 64Cu-Radiolabeled Peptide Inhibitor

    Directory of Open Access Journals (Sweden)

    Frédéric Couture

    2014-08-01

    Full Text Available The potential of PACE4 as a pharmacological target in prostate cancer has been demonstrated as this proprotein convertase is strongly overexpressed in human prostate cancer tissues and its inhibition, using molecular or pharmacological approaches, results in reduced cell proliferation and tumor progression in mouse tumor xenograft models. We developed a PACE4 high-affinity peptide inhibitor, namely, the multi-leucine (ML, and sought to determine whether this peptide could be exploited for the targeting of prostate cancer for diagnostic or molecular imaging purposes. We conjugated a bifunctional chelator 1,4,7-triazacyclononane-1,4,7- triacetic acid (NOTA to the ML peptide for copper-64 (64Cu labeling and positron emission tomography (PET– based prostate cancer detection. Enzyme kinetic assays against recombinant PACE4 showed that the NOTA-modified ML peptide displays identical inhibitory properties compared to the unmodified peptide. In vivo biodistribution of the 64Cu/NOTA-ML peptide evaluated in athymic nude mice bearing xenografts of two human prostate carcinoma cell lines showed a rapid and high uptake in PACE4-expressing LNCaP tumor at an early time point and in PACE4-rich organs. Co-injection of unlabeled peptide confirmed that tumor uptake was target-specific. PACE4-negative tumors displayed no tracer uptake 15 minutes after injection, while the kidneys, demonstrated high uptake due to rapid renal clearance of the peptide. The present study supports the feasibility of using a 64Cu/NOTA-ML peptide for PACE4-targeted prostate cancer detection and PACE4 status determination by PET imaging but also provides evidence that ML inhibitor–based drugs would readily reach tumor sites under in vivo conditions for pharmacological intervention or targeted radiation therapy.

  2. High frequency pacing of edge localized modes by injection of lithium granules in DIII-D H-mode discharges

    Energy Technology Data Exchange (ETDEWEB)

    Bortolon, A. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Maingi, R. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Mansfield, D. K. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Nagy, A. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Roquemore, A. L. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Baylor, L. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Commaux, N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jackson, G. L. [General Atomics, San Diego, CA (United States); Gilson, E. P. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Lunsford, R. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Parks, P. B. [General Atomics, San Diego, CA (United States); Chrystal, C.; Grierson, B. A. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Groebner, R. [General Atomics, San Diego, CA (United States); Haskey, S. R. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Makowski, M. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lasnier, C. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nazikian, R. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Osborne, T. [General Atomics, San Diego, CA (United States); Shiraki, D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Van Zeeland, M. A. [General Atomics, San Diego, CA (United States)

    2016-04-01

    A newly installed Lithium Granule Injector (LGI) was used to pace edge localized modes (ELM) in DIII-D. ELM pacing efficiency was studied injecting lithium granules of nominal diameter 0.3–0.9mm, speed of 50–120 m s-1 and average injection rates up to 100 Hz for 0.9mm granules and up to 700 Hz for 0.3mm granules. The efficiency of ELM triggering was found to depend strongly on size of the injected granules, with triggering efficiency close to 100% obtained with 0.9mm diameter granules, lower with smaller sizes, and weakly depending on granule velocity. Robust ELM pacing was demonstrated in ITER-like plasmas for the entire shot length, at ELM frequencies 3–5 times larger than the ‘natural’ ELM frequency observed in reference discharges. Within the range of ELM frequencies obtained, the peak ELM heat flux at the outer strike point was reduced with increasing pacing frequency. The peak heat flux reduction at the inner strike point appears to saturate at high pacing frequency. Lithium was found in the plasma core, with a concurrent reduction of metallic impurities and carbon. Overall, high frequency ELM pacing using the lithium granule injection appears to be compatible with both H-mode energy confinement and attractive H-mode pedestal characteristics, but further assessment is need

  3. High frequency pacing of edge localized modes by injection of lithium granules in DIII-D H-mode discharges

    Science.gov (United States)

    Bortolon, A.; Maingi, R.; Mansfield, D. K.; Nagy, A.; Roquemore, A. L.; Baylor, L. R.; Commaux, N.; Jackson, G. L.; Gilson, E. P.; Lunsford, R.; Parks, P. B.; Chrystal, C.; Grierson, B. A.; Groebner, R.; Haskey, S. R.; Makowski, M. J.; Lasnier, C. J.; Nazikian, R.; Osborne, T.; Shiraki, D.; Van Zeeland, M. A.

    2016-05-01

    A newly installed Lithium Granule Injector (LGI) was used to pace edge localized modes (ELM) in DIII-D. ELM pacing efficiency was studied injecting lithium granules of nominal diameter 0.3–0.9 mm, speed of 50–120 m s‑1 and average injection rates up to 100 Hz for 0.9 mm granules and up to 700 Hz for 0.3 mm granules. The efficiency of ELM triggering was found to depend strongly on size of the injected granules, with triggering efficiency close to 100% obtained with 0.9 mm diameter granules, lower with smaller sizes, and weakly depending on granule velocity. Robust ELM pacing was demonstrated in ITER-like plasmas for the entire shot length, at ELM frequencies 3–5 times larger than the ‘natural’ ELM frequency observed in reference discharges. Within the range of ELM frequencies obtained, the peak ELM heat flux at the outer strike point was reduced with increasing pacing frequency. The peak heat flux reduction at the inner strike point appears to saturate at high pacing frequency. Lithium was found in the plasma core, with a concurrent reduction of metallic impurities and carbon. Overall, high frequency ELM pacing using the lithium granule injection appears to be compatible with both H-mode energy confinement and attractive H-mode pedestal characteristics, but further assessment is needed to determine whether the projected heat flux reduction required for ITER can be met.

  4. Characterization and discrimination of polysaccharides from different species of Cordyceps using saccharide mapping based on PACE and HPTLC.

    Science.gov (United States)

    Wu, Ding-Tao; Cheong, Kit-Leong; Wang, Lan-Ying; Lv, Guang-Ping; Ju, Yao-Jun; Feng, Kun; Zhao, Jing; Li, Shao-Ping

    2014-03-15

    Polysaccharides from seven species of natural and cultured Cordyceps were firstly investigated and compared using saccharide mapping, partially acidic/enzymatic (α-amylase, β-glucanase and pectinase) digestion followed with polysaccharide analysis by using carbohydrate gel electrophoresis (PACE) and high performance thin layer chromatography (HPTLC) analysis, respectively, to obtain the comprehensive profiles of hydrolysates of the polysaccharides and their characters. The results showed that 1,4-α-D-glucosidic, 1,4-β-D-glucosidic and 1,4-α-D-galactosidic linkages were existed in natural and cultured Cordyceps sinensis, cultured Cordyceps militaris, natural Cordyceps gracilis and Cordyceps ciecadae. The similarity of polysaccharides from cultured C. militaris to natural C. sinensis was relatively high, which might contribute to the rational use of C. militaris. Moreover, different species of natural and cultured Cordyceps can be differentiated based on the saccharide mapping, which is helpful to well understand the structural characters of polysaccharides from different species of Cordyceps and to improve the quality control of polysaccharides in natural and cultured Cordyceps. PMID:24528706

  5. Cardio-respiratory interactions and relocation of heartbeats within the respiratory cycle during spontaneous and paced breathing

    International Nuclear Information System (INIS)

    The capability of respiratory sinus arrhythmia (RSA) to generate privileged locations for the occurrence of R-peaks within the respiratory cycle has been questioned in recent works, challenging the hypothesis that RSA might play a role in improving pulmonary gas exchange. We assessed such a capability submitting healthy humans to spontaneous and paced breathing (SB and PB) protocols, estimating the fraction of beats occurring during inspiration, at low, medium, and high respiratory volumes, and during the first and second half of inspiration and expiration. Then, the same fractions were computed assuming a random uniform distribution of heartbeats, and the differences were compared. The results found are as follows: (1) during PB at 6 rpm, heartbeats redistribute toward inspiration; (2) during SB and PB at 12 rpm, heartbeats tend to cluster when respiratory volume is high; (3) since such redistributions are limited in magnitude, it is possible that its physiological relevance is marginal, for instance, in terms of within-cycle variations in lung perfusion; (4) two groups of subjects with considerably different levels of RSA showed similar redistribution of heartbeats, suggesting that this phenomenon might be an underlying effect of the overall cardio-respiratory interactions, and not directly of RSA

  6. Thermal and cardiovascular strain mitigate the potential benefit of carbohydrate mouth rinse during self-paced exercise in the heat

    Directory of Open Access Journals (Sweden)

    Matthew eCramer

    2015-11-01

    Full Text Available Purpose: To determine whether a carbohydrate mouth rinse can alter self-paced exercise performance independently of a high degree of thermal and cardiovascular strain.Methods: Eight endurance-trained males performed two 40-km cycling time trials in 35°C, 60% RH while swilling a 20-ml bolus of 6.5% maltodextrin (CHO or a colour- and taste-matched placebo (PLA every 5 km. Heart rate, power output, rectal temperature (Tre, and mean skin temperature (Tsk were recorded continuously; cardiac output, oxygen uptake (VO2, mean arterial pressure (MAP, and perceived exertion (RPE were measured every 10 min. Results: Performance time and mean power output were similar between treatments, averaging 63.9 ± 3.2 and 64.3 ± 2.8 min, and 251 ± 23 and 242 ± 18 W in CHO and PLA, respectively. Power output, stroke volume, cardiac output, MAP, and VO2 decreased during both trials, increasing slightly or remaining stable during a final 2-km end-spurt. Tre, Tsk, heart rate, and RPE increased throughout exercise similarly with both treatments. Changes in RPE correlated with those in Tre (P<0.005 and heart rate (P<0.001.Conclusions: These findings suggest that carbohydrate mouth rinsing does not improve ~1-h time trial performance in hot-humid conditions, possibly due to a failure in down-regulating RPE, which may be influenced more by severe thermal and cardiovascular strain.

  7. The effects of joint torque, pace and work:rest ratio on powered hand tool operations.

    Science.gov (United States)

    Lin, Jia-Hua; McGorry, Raymond W; Maikala, Rammohan V

    2012-01-01

    Repetitive use of hand-held power tools is associated with work-related upper extremity musculoskeletal disorders. Using a pneumatic nutrunner, 21 men completed twelve 360 repetitive fastener-driving sessions on three joints (hard, soft and control) at slow and fast pace, and two different work:rest patterns. Handgrip force and perceived exertions were collected throughout each session. For the control joint, the mean grip force exerted was 39.6% of maximum voluntary exertion (MVE) whereas during hard and soft joint sessions it was 48.9% MVE and 56.9% MVE, respectively. Throughout each session, the grip force decreased, more while operating soft and hard joints as compared with the control joint (regression slope: -0.022 and -0.023, compared with -0.007 N/drive, respectively), suggesting considerable upper extremity muscular effort by participants during torque buildup. Fast work pace resulted in higher average grip forces by participants but a greater decrease in the force as the session progressed. Providing rest breaks reduced perceived exertions. The findings gain additional knowledge for assembly task design to possibly reduce the hand/arm injury risks for the operator. Practitioner Summary: Powered hand tools are widely used in assembly and manufacturing industries. However, the nature of their repetitive use on human operator biomechanical and perceptual responses is not fully understood. This study examined work-related risk factors such as joint torque, pace and work:rest ratios on powered hand tool performance. PMID:22409173

  8. Indicators of a poor outcome after temporary pacing in patients with complete atrioventricular block

    International Nuclear Information System (INIS)

    Background: Temporary pace maker (tpm) implantation is an emergency procedure, performed in symptomatic patients with AV block We report our experience of temporary pacing at a tertiary care center. It is the first study of its type from a local center. Objectives: To study the clinical course of patients after tpm implantation and to determine indicators of a poor outcome after tpm implantation. Methods: This was descriptive retrospective study. Data of all tpm procedures performed at Children Hospital from 2006 to 2012 was retrieved. We excluded patients with surgically placed tpm leads. All patients receiving transvenous tpm were included in our study. Results: Total of 12 patients received tpm, 8 were male (66.6%) and 4 were female (33.3%). Median age was 6 years ( range 1.4 -13 year ). Mean weight was 30kg, (range 8.7 - 50kg). All of them presented with complete heart block.One patient each had post diphtheria cardiomyopathy, unknown poisoning. The rest had congenital heart block. The mean period between tpm to ppm implantation was 5 days, (range 1 - 30 days). One patient spontaneously reverted to sinus rhythm(8.3%), 6 had ppm implantation (58.3%), 5 patients expired (33.3%). A low Ejection Fraction was found to be associated with a poor outcome (p<0.01). Variables that were associated with a poor outcome(mortality), were SOB (p<0.015), weak pulses (p<0.015), and hepatomegaly (p<0.01). Conclusion: Low Ejection Fraction and Heart failure is associated with a poor outcome and increased mortality in patients with complete AV block. We suggest that pacing should be considered in patients earlier, before they develop signs or symptoms of cardiac dysfunction. (author)

  9. In vivo mechanical study of helical cardiac pacing electrode interacting with canine myocardium

    Science.gov (United States)

    Zhang, Xiangming; Ma, Nianke; Fan, Hualin; Niu, Guodong; Yang, Wei

    2007-06-01

    Cardiac pacing is a medical device to help human to overcome arrhythmia and to recover the regular beats of heart. A helical configuration of electrode tip is a new type of cardiac pacing lead distal tip. The helical electrode attaches itself to the desired site of heart by screwing its helical tip into the myocardium. In vivo experiments on anesthetized dogs were carried out to measure the acute interactions between helical electrode and myocardium during screw-in and pull-out processes. These data would be helpful for electrode tip design and electrode/myocardium adherence safety evaluation. They also provide reliability data for clinical site choice of human heart to implant and to fix the pacing lead. A special design of the helical tip using strain gauges is instrumented for the measurement of the screw-in and pull-out forces. We obtained the data of screw-in torques and pull-out forces for five different types of helical electrodes at nine designed sites on ten canine hearts. The results indicate that the screw-in torques increased steplike while the torque time curves presente saw-tooth fashion. The maximum torque has a range of 0.3 1.9 N mm. Obvious differences are observed for different types of helical tips and for different test sites. Large pull-out forces are frequently obtained at epicardium of left ventricle and right ventricle lateral wall, and the forces obtained at right ventricle apex and outflow tract of right ventricle are normally small. The differences in pull-out forces are dictated by the geometrical configuration of helix and regional structures of heart muscle.

  10. In vivo mechanical study of helical cardiac pacing electrode interacting with canine myocardium

    Institute of Scientific and Technical Information of China (English)

    Xiangming Zhang; Nianke Ma; Hualin Fan; Guodong Niu; Wei Yang

    2007-01-01

    Cardiac pacing is a medical device to help human to overcome arrhythmia and to recover the regular beats of heart. A helical configuration of electrode tip is a new type of cardiac pacing lead distal tip. The helical electrode attaches itself to the desired site of heart by screwing its helical tip into the myocardium. In vivo experiments on anesthetized dogs were carried out to measure the acute interactions between helical electrode and myocardium during screw-in and pull-out processes. These data would be helpful for electrode tip design and electrode/myocardium adherence safety evaluation. They also provide reliability data for clinical site choice of human heart to implant and to fix the pacing lead.A special design of the helical tip using strain gauges is instrumented for the measurement of the screw-in and pull-out forces. We obtained the data of screw-in torques and pull-out forces for five different types of helical electrodes at nine designed sites on ten canine hearts. The results indicate that the screw-in torques increased steplike while the torque-time curves presente saw-tooth fashion. The maximum torque has a range of 0.3-1.9N mm. Obvious differences are observed for different types of helical tips and for different test sites.Large pull-out forces are frequently obtained at epicardium of left ventricle and right ventricle lateral wall, and the forces obtained at right ventricle apex and outflow tract of right ventricle are normally small. The differences in pull-out forces are dictated by the geometrical configuration of helix and regional structures of heart muscle.

  11. Instruction Design Model for Self-Paced ICT System E-Learning in an Organization

    Directory of Open Access Journals (Sweden)

    Ridi Ferdiana

    2012-08-01

    Full Text Available Adopting an Information Communication and Technology (ICT system in an organization is somewhat challenging. User diversity, heavy workload, and different skill gap make the ICT adoption process slower. This research starts from a condition that a conventional ICT learning through short workshop and guidance book is not working well. This research proposes a model called ICT instruction design model (ICT-IDM. This model provides fast track learning through integration between multimedia learning and self-paced hands-on E-learning. Through this case study, we discovered that the proposed model provides 27% rapid learning adoption rather than conventional learning model.

  12. Nechui’s Aesthetic Code: Repetition, Pacing, and Non-Purposeful Narration

    OpenAIRE

    Tarnawsky, Maxim

    2014-01-01

    Traditional and modernist comments on the mechanics of Nechui’s prose style are largely critical, focusing on what are assumed to be errors or infelicities in writing. This article examines these presumed errors and proceeds to focus on three central quali­ties of Nechui’s writing: repetition, pacing, and the absence of purposeful construction. The intention here is not to make judgments about the strengths and weaknesses of his writing but rather to point out its essential features. Two cent...

  13. Platform for Attitude Control Experiment (PACE): An Experimental Three-Axis Stabilized CubeSat

    OpenAIRE

    Tu, Jung-Kuo; Wu, Shi-Hua; Chu, Chen-Chi

    2004-01-01

    Owing to their low cost, fast development time, and multi-discipline educational purpose, CubeSats have been widely advocated by universities in recent years. However, few have employed three-axis stabilization schemes due mainly to the limitation of power and mass. The PACE, Platform for Attitude Control Experiment for short, is a three-axis stabilizing CubeSat developed at the National Cheng Kung University. It is a 20x10x10 cm3 double cube satellite weight less than 2-kg. A miniature momen...

  14. Lunar exosphere observed by MAP-PACE onboard SELENE(KAGUYA)

    Science.gov (United States)

    Yokota, Shoichiro; Saito, Yoshifumi; Tanaka, Takaaki; Asamura, Kazushi; Nishino, Masaki N.; Tsunakawa, Hideo

    The Moon has no global intrinsic magnetic field and only has a very thin atmosphere called surface-bounded exosphere. The lunar exosphere has been observed by ground-based technique on many occasions since its discovery. The alkali components such as Na or K have especially been observed to understand the generation process and the transport mechanisms. One of the loss processes of the exospheric particles is photoionization and ion-pickup process. The ionized exospheric particles are transported by the surrounding electric field. Therefore, ion measurements made from lunar orbit is another way to study the lunar exosphere as well as in-teractions between the solar wind and the planetary surface. Japanese lunar orbiter SELENE (KAGUYA), which was launched on September 14, 2007, has the in-situ plasma analyzers named MAP-PACE (MAgnetic field and Plasma experiment -Plasma energy Angle and Com-position Experiment) in order to investigate the plasma environment at 100km altitude around the Moon. PACE consists of two sensors for low energy electron measurements and two sensors for low energy ion measurements. One of the ion spectrometer, MAP-PACE IMA, which has a mass analyzer detected low-energy ions from the Moon at an altitude of 100 km. IMA has identified ion species of He+, C+, O+, Na+, K+ and Ar+. The measurements of ions from the Moon enable us to continuously monitor the lunar exosphere. The 1.5-year observation of SELENE(KAGUYA) shows that the ions from the Moon have been detected both when the Moon is exposed to the solar wind and when it is in the Earth's lobe region. The observation suggests that the solar wind is not the dominant source mechanism for the lunar exospheres. Moreover, the MAP-PACE observation shows the dependence on the solar zenith angle and the dawn-dusk asymmetry of the lunar exosphere. We report the features of the lunar exospheres obtained by the SELENE(KAGUYA) observation and discuss the source mechanism of the lunar exosphere.

  15. Effect of nifekalant on acute electrical remodelling in rapid atrial pacing canine model

    Institute of Scientific and Technical Information of China (English)

    TANG Min; ZHANG Shu; SUN Qi; HUA Wei; HUANG Cong-xin

    2006-01-01

    Background Nifekalant may prevent atrial fibrillation (AF) and possibly be useful in treatment of atrial tachyarrhythmia in patients with severe heart failure. This study investigated the electophysiologic effect of nifekalant on the acute atrial remodeling in rapid atrial pacing (RAP) model of canine.Methods Twelve mongrel dogs subjected to rapid stimulation (400 beats/min) at left atrial appendage (LAA)for 24 hours, were randomized into the control group (rapid pacing only, n=6) and the nifekalant group (intravenous nifekalant therapy immediately after RAP, n=6). Atrial electrophysiological parameters were measured in right atrium, coronary sinus, LAA, posterior wall of left atrium (PWLA) and left superior pulmonary vein (LSPV), before and after the RAP.Results In the control group, the effective refractory periods (ERP) were shortened greatly at all sites, paced dogs had substantially shorter ERPs in the high right atrium, LAA, and LSPV, but fewer changes in the PWLA,the coefficient variation of ERP (COV ERP) was increased significantly. After rapid atrial stimulation, the inducibility of AF increased significantly [induction number: pre-RAP vs post-RAP, 1.00± 0.89 vs 8.17 ± 2.79,P<0.01; duration of AF: pre-RAP vs post-RAP, (450.34± 362.59) ms vs (9975.77 ±4376.99) ms, P<0.01]. In the nifekalant group, although the ERPs were prolonged at all sites compared with those in pre-RAP state, only the value at LSPV differed significantly from that in pre-RAP state [pre-RAP vs post-RAP, (102.50±5.24) ms vs (132.51 ±5.20) ms, P<0.01]; the COV ERP did not change statistically in this group. The inducibility of AF slightly increased but insignificantly after pacing [induction number: pre-RAP vs post-RAP, 0.83 ±0.75 vs 1.67±0.82, P=0.19; duration of AF: pre-RAP vs post-RAP, (378.67±317.88) ms vs (1124.08±1109.77) ms,P=0.06]. Conduction time values did not alter significantly in either of the two groups after RAP.Conclusions In canine RAP model, nifekalant

  16. Pacing and time allocation at the micro- and meso-level within the class hour: Why pacing is important, how to study it, and what it implies for individual lesson planning

    Directory of Open Access Journals (Sweden)

    Joshua Goldsmith

    2009-11-01

    Full Text Available The topic of pacing at the level of the individual class hour has received relatively little coverage in research literature. In order to provide a research-based take on the issue, the current work surveys the existing literature, develops terminology and draws a key distinction between macro-, meso-, and micro-levels of pacing, sequencing, grading, and transitioning. In order to focus on one of pacing’s constituent sub-topics—the allocation of classroom time—this article presents a case study of a first semester college-level introductory German class at a top-tier American university. The data come from two hours of class, one each from the beginning and end of the semester, in an attempt to discover not only how pacing affects teaching synchronically but also how it might change diachronically. Utterances and gestures were transcribed in order to segment the class into activities and sub-activities, and a model for using verbal and gestural cues to perform this kind of segmentation is proposed. The paper also discusses how the teacher allocates time to different kinds of activities, considering pacing strategies that help keep students focused and “on plan” and how these pacing strategies can allow for more time and activities spent on communicative, pair-based work. It is argued that because of the case study teacher’s focus on pacing and use of various strategies to pace the class, not only researchers but also teachers might be able to generalize the micro- and meso-pacing model described in this study to the pacing of individual lessons in their own classrooms.-------------------------------------------------------------------- L’anàlisi detallada del pacing en una hora de classe és un aspecte poc tractat en la literatura científica. Per garantir una perspectiva basada en resultats empírics, aquest estudi es proposa fer un repàs a la literatura ja publicada sobre el tema, desenvolupar-ne la terminologia i distingir

  17. Process Improvement for Software Localization

    OpenAIRE

    Goncalves, Luis

    2011-01-01

    Competition in mobile industry is tougher than ever, forcing mobile manufacturers to fight for their market share. In this challenging environment, companies must release new software at a high pace and frequency. The overall purpose of this Thesis was to create a basis for a process improvement framework in localization teams. This study is specific to the case company, but the outcome can be applied to other localization teams, especially for those that work in an Agile Mode, and especi...

  18. Deaf Readers’ Response to Syntactic Complexity: Evidence from Self-Paced Reading

    Science.gov (United States)

    Traxler, Matthew J.; Corina, David P.; Morford, Jill P.; Hafer, Sarah; Hoversten, Liv J.

    2013-01-01

    This study was designed to determine the feasibility of using self-paced reading methods to study deaf readers and to assess how deaf readers respond to two syntactic manipulations. Three groups of participants read the test sentences: deaf readers, hearing monolingual English readers, and hearing bilingual readers whose second language was English. In Experiment 1, participants read sentences containing subject relative or object relative clauses. The test sentences contained semantic information that influences on-line processing outcomes (Traxler et al., 2002; 2005). All of the participant groups had greater difficulty processing sentences containing object relative clauses. This difficulty was reduced when helpful semantic cues were present. In Experiment 2, participants read active voice and passive voice sentences. The sentences were processed similarly by all three groups. Comprehension accuracy was higher in hearing readers than in deaf readers. Within deaf readers, native signers read the sentences faster and comprehended them to a higher degree than did non-native signers. These results indicate that self-paced reading is a useful method for studying sentence interpretation among deaf readers. PMID:23868696

  19. Hemodynamic Surveillance of Ventricular Pacing Effectiveness with the Transvalvular Impedance Sensor

    Directory of Open Access Journals (Sweden)

    Valeria Calvi

    2014-01-01

    Full Text Available The Transvalvular Impedance (TVI is derived between atrial and ventricular pacing electrodes. A sharp TVI increase in systole is an ejection marker, allowing the hemodynamic surveillance of ventricular stimulation effectiveness in pacemaker patients. At routine follow-up checks, the ventricular threshold test was managed by the stimulator with the supervision of a physician, who monitored the surface ECG. When the energy scan resulted in capture loss, the TVI system must detect the failure and increase the output voltage. A TVI signal suitable to this purpose was present in 85% of the tested patients. A total of 230 capture failures, induced in 115 patients in both supine and sitting upright positions, were all promptly recognized by real-time TVI analysis (100% sensitivity. The procedure was never interrupted by the physician, as the automatic energy regulation ensured full patient’s safety. The pulse energy was then set at 4 times the threshold to test the alarm specificity during daily activity (sitting, standing up, and walking. The median prevalence of false alarms was 0.336%. The study shows that TVI-based ejection assessment is a valuable approach to the verification of pacing reliability and the autoregulation of ventricular stimulation energy.

  20. Hemodynamic Surveillance of Ventricular Pacing Effectiveness with the Transvalvular Impedance Sensor.

    Science.gov (United States)

    Calvi, Valeria; Pizzimenti, Giovanni; Lisi, Marco; Doria, Giuseppe; Vasquez, Ludovico; Lisi, Francesco; Felis, Salvatore; Tempio, Donatella; Virgilio, Alfredo; Barbetta, Alberto; Di Gregorio, Franco

    2014-01-01

    The Transvalvular Impedance (TVI) is derived between atrial and ventricular pacing electrodes. A sharp TVI increase in systole is an ejection marker, allowing the hemodynamic surveillance of ventricular stimulation effectiveness in pacemaker patients. At routine follow-up checks, the ventricular threshold test was managed by the stimulator with the supervision of a physician, who monitored the surface ECG. When the energy scan resulted in capture loss, the TVI system must detect the failure and increase the output voltage. A TVI signal suitable to this purpose was present in 85% of the tested patients. A total of 230 capture failures, induced in 115 patients in both supine and sitting upright positions, were all promptly recognized by real-time TVI analysis (100% sensitivity). The procedure was never interrupted by the physician, as the automatic energy regulation ensured full patient's safety. The pulse energy was then set at 4 times the threshold to test the alarm specificity during daily activity (sitting, standing up, and walking). The median prevalence of false alarms was 0.336%. The study shows that TVI-based ejection assessment is a valuable approach to the verification of pacing reliability and the autoregulation of ventricular stimulation energy. PMID:26556408

  1. Cardiovascular strain impairs prolonged self-paced exercise in the heat.

    Science.gov (United States)

    Périard, Julien D; Cramer, Matthew N; Chapman, Phillip G; Caillaud, Corinne; Thompson, Martin W

    2011-02-01

    It has been proposed that self-paced exercise in the heat is regulated by an anticipatory reduction in work rate based on the rate of heat storage. However, performance may be impaired by the development of hyperthermia and concomitant rise in cardiovascular strain increasing relative exercise intensity. This study evaluated the influence of thermal strain on cardiovascular function and power output during self-paced exercise in the heat. Eight endurance-trained cyclists performed a 40 km simulated time trial in hot (35°C) and thermoneutral conditions (20°C), while power output, mean arterial pressure, heart rate, oxygen uptake and cardiac output were measured. Time trial duration was 64.3 ± 2.8 min (242.1 W) in the hot condition and 59.8 ± 2.6 min (279.4 W) in the thermoneutral condition (P heat was depressed from 20 min onwards compared with exercise in the thermoneutral condition (P temperature reached 39.8 ± 0.3 (hot) and 38.9 ± 0.2°C (thermoneutral; P skin temperature was ~7.5°C higher in the heat, and skin blood flow was significantly elevated (P stroke volume, cardiac output and mean arterial pressure were significantly depressed compared with the thermoneutral condition (P heat. PMID:20851861

  2. Characterizing Spatial Dynamics of Bifurcation to Alternans in Isolated Whole Rabbit Hearts Based on Alternate Pacing

    Directory of Open Access Journals (Sweden)

    Kanchan Kulkarni

    2015-01-01

    Full Text Available Sudden cardiac death instigated by ventricular fibrillation (VF is the largest cause of natural death in the USA. Alternans, a beat-to-beat alternation in the action potential duration, has been implicated as being proarrhythmic. The onset of alternans is mediated via a bifurcation, which may occur through either a smooth or a border-collision mechanism. The objective of this study was to characterize the mechanism of bifurcation to alternans based on experiments in isolated whole rabbit hearts. High resolution optical mapping was performed and the electrical activity was recorded from the left ventricle (LV epicardial surface of the heart. Each heart was paced using an “alternate pacing protocol,” where the basic cycle length (BCL was alternatively perturbed by ±δ. Local onset of alternans in the heart, BCLstart, was measured in the absence of perturbations (δ=0 and was defined as the BCL at which 10% of LV exhibited alternans. The influences of perturbation size were investigated at two BCLs: one prior to BCLstart (BCLprior=BCLstart+20 ms and one preceding BCLprior (BCLfar=BCLstart+40 ms. Our results demonstrate significant spatial correlation of the region exhibiting alternans with smooth bifurcation characteristics, indicating that transition to alternans in isolated rabbit hearts occurs predominantly through smooth bifurcation.

  3. Utilizing solid impurity granules for ELM pacing in NSTX-U

    Science.gov (United States)

    Lunsford, Robert; Roquemore, L.; Jaworski, M. A.; Kaita, R.; Maingi, R.; NSTX-U Team

    2015-11-01

    Periodic edge localized modes (ELMs) rapidly transport stored energy from the edge plasma to the divertor. These events result in abrupt heating of the plasma facing components (PFCs) which reduces their effective lifetime as well as generating a strong impurity influx. If the frequency of these ELMs can be increased through controlled triggering, also known as pacing, then the inverse relationship between the peak heat flux and the frequency of the ELMs can be utilized to prevent material damage that could result from otherwise unmitigated ELMs. At NSTX, the ability of small (300 - 1000 micron) impurity granules to trigger and pace these ELMs is being explored. In these experiments, ELMs are triggered by seeding a density perturbation within the edge-pedestal region through low speed injection and ablation of impurity granules, thus generating a localized instability. Granules are dropped from a reservoir and transit a vertical flight tube at which point a rotating impeller imparts horizontal momentum into the falling granules. This drives them into the edge of the discharge at speeds ranging from 50-150 m/s and average injection frequencies of up to 200 Hz depending upon the settings of the injector. Results from the initial laboratory injection tests of lithium, boron carbide (B4C) and vitreous carbon granules and their subsequent implementation in NSTX-U experiments will be discussed. Work supported by DOE Contract No. DE-AC02-09CH11466.

  4. The Self-Paced Graz Brain-Computer Interface: Methods and Applications

    Directory of Open Access Journals (Sweden)

    Alois Schloegl

    2007-08-01

    Full Text Available We present the self-paced 3-class Graz brain-computer interface (BCI which is based on the detection of sensorimotor electroencephalogram (EEG rhythms induced by motor imagery. Self-paced operation means that the BCI is able to determine whether the ongoing brain activity is intended as control signal (intentional control or not (non-control state. The presented system is able to automatically reduce electrooculogram (EOG artifacts, to detect electromyographic (EMG activity, and uses only three bipolar EEG channels. Two applications are presented: the freeSpace virtual environment (VE and the Brainloop interface. The freeSpace is a computer-game-like application where subjects have to navigate through the environment and collect coins by autonomously selecting navigation commands. Three subjects participated in these feedback experiments and each learned to navigate through the VE and collect coins. Two out of the three succeeded in collecting all three coins. The Brainloop interface provides an interface between the Graz-BCI and Google Earth.

  5. Maintained cerebral oxygenation during maximal self-paced exercise in elite Kenyan runners.

    Science.gov (United States)

    Santos-Concejero, J; Billaut, F; Grobler, L; Oliván, J; Noakes, T D; Tucker, R

    2015-01-15

    The purpose of this study was to analyze the cerebral oxygenation response to maximal self-paced and incremental exercise in elite Kenyan runners from the Kalenjin tribe. On two separate occasions, 15 elite Kenyan distance runners completed a 5-km time trial (TT) and a peak treadmill speed test (PTS). Changes in cerebral oxygenation were monitored via near-infrared spectroscopy through concentration changes in oxy- and deoxyhemoglobin (Δ[O2Hb] and Δ[HHb]), tissue oxygenation index (TOI), and total hemoglobin index (nTHI). During the 5-km TT (15.2 ± 0.2 min), cerebral oxygenation increased over the first half (increased Δ[O2Hb] and Δ[HHb]) and, thereafter, Δ[O2Hb] remained constant (effect size, ES = 0.33, small effect), whereas Δ[HHb] increased until the end of the trial (P Kalenjin tribe are able to maintain their cerebral oxygenation within a stable range during a self-paced maximal 5-km time trial, but not during an incremental maximal test. This may contribute to their long-distance running success. PMID:25414248

  6. Usefulness of hemodynamic sensors for physiologic cardiac pacing in heart failure patients.

    Science.gov (United States)

    Occhetta, Eraldo; Bortnik, Miriam; Marino, Paolo

    2011-01-01

    The rate adaptive sensors applied to cardiac pacing should respond as promptly as the normal sinus node with an highly specific and sensitive detection of the need of increasing heart rate. Sensors operating alone may not provide optimal heart responsiveness: central venous pH sensing, variations in the oxygen content of mixed venous blood, QT interval, breathing rate and pulmonary minute ventilation monitored by thoracic impedance variations, activity sensors. Using sensors that have different attributes but that work in a complementary manners offers distinct advantages. However, complicated sensors interactions may occur. Hemodynamic sensors detect changes in the hemodynamic performances of the heart, which partially depends on the autonomic nervous system-induced inotropic regulation of myocardial fibers. Specific hemodynamic sensors have been designed to measure different expression of the cardiac contraction strength: Peak Endocardial Acceleration (PEA), Closed Loop Stimulation (CLS) and TransValvular Impedance (TVI), guided by intraventricular impedance variations. Rate-responsive pacing is just one of the potential applications of hemodynamic sensors in implantable pacemakers. Other issues discussed in the paper include: hemodynamic monitoring for the optimal programmation and follow up of patients with cardiac resynchronization therapy; hemodynamic deterioration impact of tachyarrhythmias; hemodynamic upper rate limit control; monitoring and prevention of vasovagal malignant syncopes. PMID:21461359

  7. The Australian history of cardiac pacing: memories from a bygone era.

    Science.gov (United States)

    Mond, Harry G; Wickham, Geoffrey G; Sloman, J Graeme

    2012-06-01

    Although Dr Albert Hyman in New York is believed to have built the first cardiac pacemaker in 1932, he acknowledges Dr Mark Lidwell in Sydney, Australia as having not only built a pacemaker, but also successfully used it to resuscitate a newborn infant in or before 1929. Fully implantable pacemakers, however, were not possible until 1958, following the development of the silicon transistor. Within three years of that first implant, a pulse generator attached to epicardial leads was implanted at the Royal Melbourne Hospital. About the same time, an engineer in Sydney with intermittent complete heart block who had received epicardial leads and an external pulse generator proposed a simple sensing circuit, leading to the design of the first demand pacing system. By the mid 1960s, physicians were inserting transvenous leads in the right ventricle attached to pulse generators implanted in the anterior abdominal wall. In 1963, an Australian pacemaker company, Telectronics, was founded in Sydney. This innovative company-designed many of the features of transvenous leads and pulse generators we take for granted today. Australia also played a leading role in the design or early evaluation of the lithium power source, lead fixation, steroid elution, automatic anti-tachycardia pacing algorithms and the minute ventilation rate adaptive sensor. This manuscript describes the challenges and frustrations of those pioneers: physicians, surgeons and biomedical engineers. PMID:22033147

  8. Observation of ions from the Moon by MAP-PACE IMA onboard SELENE(KAGUYA)

    Science.gov (United States)

    Yokota, Shoichiro; Saito, Yoshifumi; Tanaka, Takaaki; Asamura, Kazushi; Nishino, Masaki; Tsunakawa, Hideo

    2010-05-01

    The Moon has no global intrinsic magnetic field and only has a very thin atmosphere. Ion measurements made from lunar orbit give us the information regarding interactions between the solar wind and the planetary surface. The ion mass spectrometry also provides the surface composition and the source and loss mechanisms of planetary tenuous atmospheres. An ion energy mass spectrometer MAP-PACE IMA onboard a lunar orbiter SELENE(KAGUYA) has detected low-energy ions from the Moon at an altitude of 100 km. IMA has identified ion species of He+, C+, O+, Na+, K+ and Ar+. The measurements of ions from the Moon enable us to continuously monitor the lunar exospheres. The 1.5-year observation of SELENE(KAGUYA) shows that the ions from the Moon have been detected both when the Moon is exposed to the solar wind and when it is in the Earth's lobe region. The observation suggests that the solar wind is not the dominant source mechanism for the lunar exospheres. Moreover, the MAP-PACE IMA shows the dependence on the solar zenith angle and the dawn-dusk asymmetry. We report the features of the lunar exospheres obtained by the SELENE(KAGUYA) observation and discuss the source mechanism of the lunar exospheres.

  9. A 'slow pace of life' in Australian old-endemic passerine birds is not accompanied by low basal metabolic rates.

    Science.gov (United States)

    Bech, Claus; Chappell, Mark A; Astheimer, Lee B; Londoño, Gustavo A; Buttemer, William A

    2016-05-01

    Life history theory suggests that species experiencing high extrinsic mortality rates allocate more resources toward reproduction relative to self-maintenance and reach maturity earlier ('fast pace of life') than those having greater life expectancy and reproducing at a lower rate ('slow pace of life'). Among birds, many studies have shown that tropical species have a slower pace of life than temperate-breeding species. The pace of life has been hypothesized to affect metabolism and, as predicted, tropical birds have lower basal metabolic rates (BMR) than temperate-breeding birds. However, many temperate-breeding Australian passerines belong to lineages that evolved in Australia and share 'slow' life-history traits that are typical of tropical birds. We obtained BMR from 30 of these 'old-endemics' and ten sympatric species of more recently arrived passerine lineages (derived from Afro-Asian origins or introduced by Europeans) with 'faster' life histories. The BMR of 'slow' temperate-breeding old-endemics was indistinguishable from that of new-arrivals and was not lower than the BMR of 'fast' temperate-breeding non-Australian passerines. Old-endemics had substantially smaller clutches and longer maximal life spans in the wild than new arrivals, but neither clutch size nor maximum life span was correlated with BMR. Our results suggest that low BMR in tropical birds is not functionally linked to their 'slow pace of life' and instead may be a consequence of differences in annual thermal conditions experienced by tropical versus temperate species. PMID:26874837

  10. The second messenger system(s) mediating the secretion of atrial natriuretic peptide (ANP) from the isolated rat heart during rapid cardiac pacing.

    Science.gov (United States)

    Doubell, A F

    1989-01-01

    This study demonstrates that rapid cardiac pacing elevates Atrial Natriuretic Peptide (ANP) levels, independently from atrial stretch. The second messenger system mediating this response was examined. The phosphoinositide system, generally regarded to be important in mediating ANP release, was shown to play only a modulating role during rapid cardiac pacing. The main mediator would appear to be calcium, and a non-calmodulin dependent, calcium mediated system controlling ANP release during rapid cardiac pacing is suggested. PMID:2532285

  11. Human radiation studies: Remembering the early years. Oral history of physiologist Nello Pace, Ph.D., August 16, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    Dr. Nello Pace was interviewed by representatives of the US DOE Office of Human Radiation Experiments (OHRE). Dr. Pace was selected fro the interview because of the positions he held with the US Navy, at the University of California, Berkeley, and as Director of the White Mountain Research Station near Bishop, California. Following a brief biographical sketch, Dr. Pace related his remembrances concerning tritium injections experiments in animals and humans during World War II, the development of Medical Physics Degree Programs at UC Berkeley, conducting the first radiation survey at Nagasaki after the bomb, and the establishment of a research laboratory at White Mountain. He also offers reflections on Shields Warren and comments on the public`s attitudes towards radiation both then and now.

  12. Human radiation studies: Remembering the early years. Oral history of physiologist Nello Pace, Ph.D., August 16, 1994

    International Nuclear Information System (INIS)

    Dr. Nello Pace was interviewed by representatives of the US DOE Office of Human Radiation Experiments (OHRE). Dr. Pace was selected fro the interview because of the positions he held with the US Navy, at the University of California, Berkeley, and as Director of the White Mountain Research Station near Bishop, California. Following a brief biographical sketch, Dr. Pace related his remembrances concerning tritium injections experiments in animals and humans during World War II, the development of Medical Physics Degree Programs at UC Berkeley, conducting the first radiation survey at Nagasaki after the bomb, and the establishment of a research laboratory at White Mountain. He also offers reflections on Shields Warren and comments on the public's attitudes towards radiation both then and now

  13. Utváření lokální identity v malé obci (Paceřice)

    OpenAIRE

    Ludvíková, Sabina

    2013-01-01

    This bachelor thesis dealt with the topic of formation of local identity in a small municipality named Paceřice. The aim was to determine what roles have been playing functional associations between formation and stregthening of local identity amongst Paceřice citizens and how that affects cohesion in local communities of Paceřice. Scientific methods which have been used are a study of literature, a secondary analysis of data from a local magazine "Paceřák" and semi-standardized interviews wi...

  14. Immune investment is explained by sexual selection and pace-of-life, but not longevity in parrots (Psittaciformes.

    Directory of Open Access Journals (Sweden)

    Darryl B Edwards

    Full Text Available Investment in current reproduction should come at the expense of traits promoting future reproduction, such as immunity and longevity. To date, comparative studies of pace-of-life traits have provided some support for this, with slower paced species having greater immune function. Another means of investment in current reproduction is through secondary sexual characters (SSC. Investment in SSC's is considered costly, both in terms of immunity and longevity, with greater costs being borne by species with more elaborate traits. Yet within species, females prefer more ornate males and those males are typically immunologically superior. Because of this, predictions about the relationship between immunity and SSC's across species are not clear. If traits are costly, brighter species should have reduced immune function, but the opposite is true if SSC's arise from selection for more immunocompetent individuals. My approach was to investigate immune investment in relation to SSC's, pace-of-life and longevity while considering potentially confounding ecological factors. To do so I assessed leukocyte counts from in a novel group, the Psittaciformes. Investment in SSC's best explained investment in immunity: species with brighter plumage had higher leukocyte counts and those with a greater degree of sexual dichromatism had fewer. Ecological variables and pace-of-life models tended to be poor predictors of immune investment. However, shorter incubation periods were associated with lower leukocyte counts supporting the notion that species with a fast pace-of-life invest less in immunity. These results suggest that investment in reproduction in terms of fast pace-of-life and sexual dichromatism results in reduced immunity; however, investment in plumage colour per se does not impose a cost on immunity across species.

  15. Comparison of the Event-Related Desynchronization during Self-Paced Movement and when playing a Nintendo Wii Game

    OpenAIRE

    Nikola Šobajić; Andrej Savić

    2011-01-01

    We compared pre-movement event-related desynchronization (ERD) of μ rhythm over the primary motor cortex using surface electrodes in a group of five healthy subjects during self-paced wrist movement and the wrist movement when playing a Nintendo Wii. We present a method that uses ERD to detect the onset of movement in single-trial electroencephalographic (EEG) data. This algorithm produced a mean detection accuracy of 83% for the self-paced movement and 75% for the Wii-included sessions, with...

  16. Influence of age and sex on pacing during Sprint, Olympic, Half-Ironman and Ironman triathlons: Part B

    OpenAIRE

    Sam Shi Xuan Wu; Jeremiah J Peiffer; Jeanick Brisswalter; Wing Y Lau; Kazunori Nosaka; Abbiss, Chris R.

    2014-01-01

    The aim of this study was to investigate the influence of biological sex and age on the pacing strategies adopted by non-drafting top triathletes during the cycle and run disciplines of a Sprint, Olympic, half-Ironman and Ironman triathlon. Split times of the top 20% non-elite males (n=468) and females (n=146) were determined using official race transponders and a video capture system for pre-determined sections of the cycle and run disciplines of four triathlon distances. Indices of pacing w...

  17. Large-scale ocean circulation-cloud interactions reduce the pace of transient climate change

    Science.gov (United States)

    Trossman, D. S.; Palter, J. B.; Merlis, T. M.; Huang, Y.; Xia, Y.

    2016-04-01

    Changes to the large-scale oceanic circulation are thought to slow the pace of transient climate change due, in part, to their influence on radiative feedbacks. Here we evaluate the interactions between CO2-forced perturbations to the large-scale ocean circulation and the radiative cloud feedback in a climate model. Both the change of the ocean circulation and the radiative cloud feedback strongly influence the magnitude and spatial pattern of surface and ocean warming. Changes in the ocean circulation reduce the amount of transient global warming caused by the radiative cloud feedback by helping to maintain low cloud coverage in the face of global warming. The radiative cloud feedback is key in affecting atmospheric meridional heat transport changes and is the dominant radiative feedback mechanism that responds to ocean circulation change. Uncertainty in the simulated ocean circulation changes due to CO2 forcing may contribute a large share of the spread in the radiative cloud feedback among climate models.

  18. Characterizing the concept of activity pacing as a non-pharmacological intervention in rheumatology care

    DEFF Research Database (Denmark)

    Cuperus, N; Vliet Vlieland, Tpm; Brodin, N;

    2016-01-01

    OBJECTIVE: To develop a consensual list of the most important aspects of activity pacing (AP) as an intervention within the context of non-pharmacological rheumatology care. METHOD: An international, multidisciplinary expert panel comprising 60 clinicians and/or healthcare providers experienced in...... AP across 12 different countries participated in a Delphi survey. Over four Delphi rounds, the panel identified and ranked the most important goals of AP, behaviours of AP (the actions people take to meet the goal of AP), strategies to change behaviour in AP, and contextual factors that should be...... acknowledged when instructing AP. Additionally, topics for future research on AP were formulated and prioritized. RESULTS: The Delphi panel prioritized 9 goals, 11 behaviours, 9 strategies to change behaviour, and 10 contextual factors of AP. These items were integrated into a consensual list containing the...

  19. Increases in myocardial workload induced by rapid atrial pacing trigger alterations in global metabolism.

    Directory of Open Access Journals (Sweden)

    Aslan T Turer

    Full Text Available To determine whether increases in cardiac work lead to alterations in the plasma metabolome and whether such changes arise from the heart or peripheral organs.There is growing evidence that the heart influences systemic metabolism through endocrine effects and affecting pathways involved in energy homeostasis.Nineteen patients referred for cardiac catheterization were enrolled. Peripheral and selective coronary sinus (CS blood sampling was performed at serial timepoints following the initiation of pacing, and metabolite profiling was performed by liquid chromatography-mass spectrometry (LC-MS.Pacing-stress resulted in a 225% increase in the median rate·pressure product from baseline. Increased myocardial work induced significant changes in the peripheral concentration of 43 of 125 metabolites assayed, including large changes in purine [adenosine (+99%, p = 0.006, ADP (+42%, p = 0.01, AMP (+79%, p = 0.004, GDP (+69%, p = 0.003, GMP (+58%, p = 0.01, IMP (+50%, p = 0.03, xanthine (+61%, p = 0.0006], and several bile acid metabolites. The CS changes in metabolites qualitatively mirrored those in the peripheral blood in both timing and magnitude, suggesting the heart was not the major source of the metabolite release.Isolated increases in myocardial work can induce changes in the plasma metabolome, but these changes do not appear to be directly cardiac in origin. A number of these dynamic metabolites have known signaling functions. Our study provides additional evidence to a growing body of literature on metabolic 'cross-talk' between the heart and other organs.

  20. Functional remodeling of Ca2+-activated Cl- channel in pacing induced canine failing heart

    Institute of Scientific and Technical Information of China (English)

    Ning Li; Kejuan Ma; Siyong Teng; Jonathan C.Makielski; Jielin Pu

    2008-01-01

    Objective To determine whether Ca2+ activated Cl- current(Icl(Ca)) contributes to the functional remodeling of the failing heart.Methods Whole cell patch-clamp recording technique was employed to record the Icl(Ca) in cardiac myocytes enzymatically isolatedfrom rapidly pacing induced canine failing hearts at room temperature and compared that of the normal hearts (Nor).Results Thecurrent density of DIDS(200M)sensitive Icl(Ca) induced by intracellular Ca2+ release trigged by L-type Ca2+ current(Ica,L)wassignificantly decreased in heart failare(HE)cells compared to Nor cells.At membrane voltage of 20mV,the Icl(Ca) density was 3.02±0.54 pA/pF in Nor(n=6)vs.1.31±0.25 pA/pF in HF(n=8)cells,(P<0.01),while the averaged Ica,L density did not show differencebetween two groups.The time constant of current decay of Icl(Ca) was similar in both types of cells.On the other hand,in intra cellularCa2+ clamped mode,where the[Ca2+];was maintained at 100nmol/L,Icl(Ca) density be increased significantly in HF cells when themembrane voltage at+30mV or higher.Conclusions Our results suggest that Icl(Ca) density was decreased in pacing induced failingheart but the channel function be enhanced.Impaired Ca2+ handing in HF cells rather than reduced,Icl(Ca) channel function itself may havecaused this abnormality.The Icl(Ca) density reduction might contribute to the prolongation of action potential in failing heart.The Icl(Ca)channel function up-rugulation is likely to cause cardiac arrhythmia by inducing a delayed after depolarization,when Ca2+ overloadoccurred in diastolic failing heart cells.

  1. A global cyclostratigraphic framework constrains the timing and pacing of environmental changes over the Late Devonian (Frasnian - Famennian) mass extinction

    Science.gov (United States)

    De Vleeschouwer, David; Da Silva, Anne-Christine; Day, James E.; Whalen, Michael; Claeys, Philippe

    2016-04-01

    Milankovitch cycles (obliquity, eccentricity and precession) result in changes in the distribution of solar energy over seasons, as well as over latitudes, on time scales of ten thousands of years to millions of years. These changing patterns in insolation have induced significant variations in Earth's past climate over the last 4.5 billion years. Cyclostratigraphy and astrochronology utilize the geologic imprint of such quasi-cyclic climatic variations to measure geologic time. In recent years, major improvements of the Geologic Time Scale have been proposed through the application of cyclostratigraphy, mostly for the Mesozoic and Cenozoic (Gradstein et al., 2012). However, the field of Paleozoic cyclostratigraphy and astrochronology is still in its infancy and the application of cyclostratigraphic techniques in the Paleozoic allows for a whole new range of research questions. For example, unraveling the timing and pacing of environmental changes over the Late Devonian mass extinction on a 105-year time-scale concerns such a novel research question. Here, we present a global cyclostratigraphic framework for late Frasnian to early Famennian climatic and environmental change, through the integration of globally distributed sections. The backbone of this relative time scale consists of previously published cyclostratigraphies for western Canada and Poland (De Vleeschouwer et al., 2012; De Vleeschouwer et al., 2013). We elaborate this Euramerican base by integrating new proxy data -interpreted in terms of astronomical climate forcing- from the Iowa basin (USA, magnetic susceptibility and carbon isotope data) and Belgium (XRF and carbon isotope data). Next, we expand this well-established cyclostratigraphic framework towards the Paleo-Tethys Ocean, using magnetic susceptibility and carbon isotope records from the Fuhe section in South China (Whalen et al., 2015). The resulting global cyclostratigraphic framework implies an important refinement of the late Frasnian to

  2. Fast self paced listening times in syntactic comprehension is aphasia -- implications for deficits

    Directory of Open Access Journals (Sweden)

    Jennifer Michaud

    2015-04-01

    Full Text Available Sixty one people with aphasia (pwa and forty one matched controls were tested for the ability to understand sentences that required the ability to assign particular syntactic structures. Participants paced themselves word-by-word through twenty examples of eleven spoken sentence types and indicated which of two pictures corresponded to the meaning of each sentence. Sentences were developed in pairs such that comprehension of the experimental version of a pair required an aspect of syntactic processing not required in the corresponding baseline sentence. The need for the syntactic operations required only in the experimental version was triggered at a “critical word” in the experimental sentence. Listening times for critical words in experimental sentences were compared to those for corresponding words in the corresponding baseline sentences. We adjusted self paced listening times for word duration by subtracting word durations from tag-to-tag self paced listening times to correct for word duration, yielding what we have previously called “corrected listening times.” Corrected listening times above ceiling (10,000 msec for sentence-final words and 5,000 msec for all other words were discarded. For controls, this led to 0.2% of data being discarded and for PWAs 2.2% were discarded. Corrected listening times that were more than 3 standard deviations above or below the mean for that sentence type for each subject were adjusted either down to the upper limit or up to the lower limit of the 3SD range (not discarded. For accurate sentences, 1.7% of the control data were adjusted and 1.8% of the aphasic data were adjusted. For inaccurate sentences, 10% of the corrected listening times were adjusted for controls and 3.3% for aphasics. Our interest is in incremental parsing and interpretation. The measure we used of this process was the residual of a regression of corrected self paced listening times for critical words in experimental sentences

  3. Is Rhythm Control with Pulmonary Vein Isolation Superior to Rate Control with AV Nodal Ablation in Patients with Heart Failure?

    Directory of Open Access Journals (Sweden)

    Dhanunjaya Lakkireddy MD, FACC

    2008-12-01

    Full Text Available Pulmonary-vein isolation is increasingly being used to treat atrial fibrillation in patients with heart failure. Is Pulmonary vein isolation better than AV nodal ablation with bi-ventricular pacing in patients with heart failure?

  4. An integrated optical coherence microscopy imaging and optical stimulation system for optogenetic pacing in Drosophila melanogaster (Conference Presentation)

    Science.gov (United States)

    Alex, Aneesh; Li, Airong; Men, Jing; Jerwick, Jason; Tanzi, Rudolph E.; Zhou, Chao

    2016-03-01

    Electrical stimulation is the clinical standard for cardiac pacing. Although highly effective in controlling cardiac rhythm, the invasive nature, non-specificity to cardiac tissues and possible tissue damage limits its applications. Optogenetic pacing of the heart is a promising alternative, which is non-invasive and more specific, has high spatial and temporal precision, and avoids the shortcomings in electrical stimulation. Drosophila melanogaster, which is a powerful model organism with orthologs of nearly 75% of human disease genes, has not been studied for optogenetic pacing in the heart. Here, we developed a non-invasive integrated optical pacing and optical coherence microscopy (OCM) imaging system to control the heart rhythm of Drosophila at different developmental stages using light. The OCM system is capable of providing high imaging speed (130 frames/s) and ultrahigh imaging resolutions (1.5 μm and 3.9 μm for axial and transverse resolutions, respectively). A light-sensitive pacemaker was developed in Drosophila by specifically expressing the light-gated cation channel, channelrhodopsin-2 (ChR2) in transgenic Drosophila heart. We achieved non-invasive and specific optical control of the Drosophila heart rhythm throughout the fly's life cycle (larva, pupa, and adult) by stimulating the heart with 475 nm pulsed laser light. Heart response to stimulation pulses was monitored non-invasively with OCM. This integrated non-invasive optogenetic control and in vivo imaging technique provides a novel platform for performing research studies in developmental cardiology.

  5. Creatine kinase and creatine kinase subunit-B in coronary sinus blood in pacing-induced angina pectoris

    DEFF Research Database (Denmark)

    Bagger, J P; Ingerslev, J; Heinsvig, E M

    1982-01-01

    In nine out of 10 patients with angiographic documented coronary artery disease, pacing-induced angina pectoris provoked myocardial production of lactate, whereas no significant release of either creatine kinase or creatine kinase subunit-B to coronary sinus and peripheral venous blood could be...

  6. Children's Use of Self-Paced Slideshows: An Extension of the Video Deficit Effect?

    Science.gov (United States)

    Sage, Kara D.; Baldwin, Dare

    2015-01-01

    Past research has established that children typically learn better from live demonstrations than from two-dimensional (2D) media. In the present set of experiments, we investigated the efficacy of a new 2D learning medium-the self-paced slideshow. A primary goal was to determine whether the "video deficit effect" extended to self-paced…

  7. The role of the entry-and-stretch phase at the different paces of race in front crawl swimming.

    Science.gov (United States)

    Samson, Mathias; Monnet, Tony; Bernard, Anthony; Lacouture, Patrick; David, Laurent

    2015-01-01

    The aim of this study was to determine the role played by the entry-and-stretch phase in the coordination of swimming, at the different paces of race. Three national level swimmers (two men and one woman) were recorded, in lateral and bottom views, in three swimming paces: sprint (50 m and 100 m), middle-distance (200 m and 400 m) and long-distance (800 m and 1500 m). Anatomical landmark positions were obtained by manual digitalisation of the videos. Computational fluid dynamics and experimental studies (with a strain gauge balance and particle image velocimetry method) were used to measure and to calculate the external forces applied to the hand and to the forearm and to visualise the flow around the profile. Entry-and-stretch is the phase which varies the most according to the swimming pace. This phase can be decomposed into two sub-phases: one, the extension forward coordinated with the insweep of the opposite arm, and another one, the rotation downward coordinated with the upsweep. Results show that, at the three paces, this phase is not propulsive and could contribute essentially to maintain the horizontal balance of the body. PMID:25654468

  8. Self-Paced Tutorial Courses for Mineral Science - Metallurgy Departments. Final Progress Report (July 1975-August 1980).

    Science.gov (United States)

    Twidwell, L. G.

    Four courses in extractive metallurgy (Pyrometallurgy, Hydrometallurgy, Electrometallurgy; and Physical Chemistry of Iron and Steel) were prepared in a modular, self-paced format. Development of the course materials included: (1) preparation of course outlines by unit coordinators and advisory committees; (2) approval of course outlines (included…

  9. High-Rate Pacing Reduces Variability of Repolarization and Prevents Repolarization-Dependent Arrhythmias in Dogs With Chronic AV Block

    DEFF Research Database (Denmark)

    Oosterhoff, Peter; Thomsen, Morten Bækgaard; Maas, Joep N;

    2010-01-01

    rates (60–65 bpm vs 100–110 bpm) in 7 dogs with chronic atrioventricular block, while recording right and left ventricular (LV) monophasic action potential (MAP) and LV electrogram (EGM). Simulations showed a sampling frequency of 500 Hz is sufficient to capture relevant STV values. High-rate pacing...

  10. Examining the Effectiveness of a Semi-Self-Paced Flipped Learning Format in a College General Chemistry Sequence

    Science.gov (United States)

    Hibbard, Lisa; Sung, Shannon; Wells, Breche´

    2016-01-01

    Flipped learning has come to the forefront in education. It maximizes learning by moving content delivery online, where learning can be self-paced, allowing for class time to focus on student-centered active learning. This five-year cross-sectional study assessed student performance in a college general chemistry for majors sequence taught by a…

  11. Atrial fibrillation in patients with sick sinus syndrome: the association with PQ-interval and percentage of ventricular pacing

    DEFF Research Database (Denmark)

    Nielsen, Jens Cosedis; Thomsen, Poul Erik B; Højberg, Søren; Møller, Mogens; Riahi, Sam; Dalsgaard, Dorthe; Mortensen, Leif; Nielsen, Tonny; Asklund, Mogens; Friis, Elsebeth V; Christensen, Per; Simonsen, Erik H; Eriksen, Ulrik H; Jensen, Gunnar; Svendsen, Jesper H; Toff, William D; Healey, Jeffrey S; Andersen, Henning

    2012-01-01

    between minimal-paced programmed AVI = 100 and >100 ms (median value), respectively (P= 0.60).ConclusionsThe present study indicates that a longer baseline PQ-interval is associated with an increased risk of AF in patients with sick sinus syndrome. Atrial fibrillation burden is not associated with the...

  12. At Their Own Pace: Interim Findings from an Evaluation of a Computer-Assisted, Modular Approach to Developmental Math

    Science.gov (United States)

    Gardenhire, Alissa; Diamond, John; Headlam, Camielle; Weiss, Michael J.

    2016-01-01

    Community colleges nationwide are looking for solutions to help students complete developmental (remedial) math--a known barrier to graduation. Some are offering computer-assisted, modular developmental math courses that allow students to earn credits incrementally and move through the curriculum at their own pace. One of these modularized…

  13. Planning the Marketing Strategy. PACE Revised. Level 2. Unit 6. Research & Development Series No. 240BB6.

    Science.gov (United States)

    Ashmore, M. Catherine; Pritz, Sandra G.

    This unit on planning marketing strategy for a small business, the sixth in a series of 18 modules, is on the second level of the revised PACE (Program for Acquiring Competence in Entrepreneurship) comprehensive curriculum. Geared to advanced secondary and beginning postsecondary or adult students, the modules provide an opportunity to learn about…

  14. The challenge of engaging all students via self-paced interactive e-learning tutorials for introductory physics

    CERN Document Server

    DeVore, Seth; Singh, Chandralekha

    2016-01-01

    As research-based self-paced e-learning tools become increasingly available, a critical issue educators encounter is implementing strategies to ensure that all students engage with them as intended. Here, we discuss the effectiveness of research-based e-learning tutorials as self-paced learning tools in large enrollment brick and mortar introductory physics courses. These interactive tutorials were developed via research in physics education and were found to be effective for a diverse group of introductory physics students in one-on-one implementation. Instructors encouraged the use of these self-paced tools in a self-paced learning environment by telling students that they would be helpful for solving the assigned homework problems and that the underlying physics principles in the tutorial problems would be similar to those in the in-class quizzes (which we call paired problems). We find that many students, who struggled in the courses in which these adaptive e-learning tutorials were assigned as a self-stu...

  15. Reclaiming Students' Voices: Fourth Graders' Discussion of the Great Migration in a Climate of Paced Curriculum

    Science.gov (United States)

    Hill, K. Dara

    2013-01-01

    In this study, a researcher investigated how teachers can negotiate their practice to engage high-needs students whose life experiences are not reflected in the curriculum, without compromising administrative demands for standardized curriculum and pacing. A fourth-grade teacher in a high-achieving, high-poverty urban primary school in Detroit…

  16. Fetal critical aortic stenosis with natural improvement of hydrops fetalis due to spontaneous relief of severe restrictive atrial communication.

    Science.gov (United States)

    Ide, Tetsuya; Miyoshi, Takekazu; Kitano, Masataka; Kurosaki, Ken-ichi; Yoshimatsu, Jun

    2015-07-01

    We describe a rare case of fetal critical aortic stenosis with spontaneous relief of severe restrictive atrial communication, resulting in complete resolution of hydrops fetalis in utero. Fetal ultrasonography showed hydrops fetalis caused by critical aortic stenosis with a severely restrictive foramen ovale and severe mitral regurgitation at 23 weeks of gestation. Hydrops fetalis, however, spontaneously resolved, showing an obvious increase of flow through the foramen ovale and pulmonary vein at 26 weeks of gestation. The neonate required balloon dilation of the aortic valve and balloon atrioseptostomy immediately after birth and also received bilateral pulmonary artery banding and arterial duct stenting 1 week later. The patient was in good condition after conversion to biventricular circulation via Ross procedure at 8 months old. The present case suggests that atrioseptostomy as a fetal intervention may improve outcome in even a hydropic condition. PMID:25772579

  17. Impact of right-ventricular apical pacing on the optimal left-ventricular lead positions measured by phase analysis of SPECT myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Guang-Uei [Chang Bing Show Chwan Memorial Hospital, Changhua (China); China Medical University, Department of Biomedical Imaging and Radiological Science, Taichung (China); Huang, Jin-Long [Taichung Veterans General Hospital, Cardiovascular Center, Taichung (China); School of Medicine, National Yang-Ming University, Institute of Clinical Medicine, and Cardiovascular Research Institute, Department of Medicine, Taipei (China); Chung-Shan Medical University, Department of Medicine, School of Medicine, Taichung (China); Lin, Wan-Yu; Tsai, Shih-Chung [Taichung Veterans General Hospital, Department of Nuclear Medicine, Taichung (China); Wang, Kuo-Yang [Taichung Veterans General Hospital, Cardiovascular Center, Taichung (China); Chung-Shan Medical University, Department of Medicine, School of Medicine, Taichung (China); Chen, Shih-Ann [School of Medicine, National Yang-Ming University, Institute of Clinical Medicine, and Cardiovascular Research Institute, Department of Medicine, Taipei (China); Taipei Veterans General Hospital, Division of Cardiology, Department of Medicine, Taipei (China); Lloyd, Michael S.; Chen, Ji [Emory University, Department of Radiology and Imaging Sciences, Atlanta, GA (United States)

    2014-06-15

    The use of SPECT phase analysis to optimize left-ventricular (LV) lead positions for cardiac resynchronization therapy (CRT) was performed at baseline, but CRT works as simultaneous right ventricular (RV) and LV pacing. The aim of this study was to assess the impact of RV apical (RVA) pacing on optimal LV lead positions measured by SPECT phase analysis. This study prospectively enrolled 46 patients. Two SPECT myocardial perfusion scans were acquired under sinus rhythm with complete left bundle branch block and RVA pacing, respectively, following a single injection of {sup 99m}Tc-sestamibi. LV dyssynchrony parameters and optimal LV lead positions were measured by the phase analysis technique and then compared between the two scans. The LV dyssynchrony parameters were significantly larger with RVA pacing than with sinus rhythm (p ∝0.01). In 39 of the 46 patients, the optimal LV lead positions were the same between RVA pacing and sinus rhythm (kappa = 0.861). In 6 of the remaining 7 patients, the optimal LV lead positions were along the same radial direction, but RVA pacing shifted the optimal LV lead positions toward the base. The optimal LV lead positions measured by SPECT phase analysis were consistent, no matter whether the SPECT images were acquired under sinus rhythm or RVA pacing. In some patients, RVA pacing shifted the optimal LV lead positions toward the base. This study supports the use of baseline SPECT myocardial perfusion imaging to optimize LV lead positions to increase CRT efficacy. (orig.)

  18. The comparative effects of teacher-demonstration and self-paced instruction on concept acquisition and problem-solving skills of college level chemistry students

    Science.gov (United States)

    Eniaiyeju, Paul A.

    A comparison is made of the relative effectiveness of teacher-demonstration and self-paced modes of teaching concepts and problem-solving skills in chemistry. Sixty students were randomized into two treatment groups. A self-paced instructional package was used by subjects in the self-paced group. Subjects in the second group were taught by a teacher who used the same self-paced package. Results of the analyses of variance performed showed that the selfpaced mode of instruction was significantly more effective for teaching concepts and problem-solving skills. An attitude test was given at the end of the third unit. Results of the test showed that most students preferred the self-paced instruction to the teacher-demonstration method.

  19. Protocol for the PACE trial: A randomised controlled trial of adaptive pacing, cognitive behaviour therapy, and graded exercise as supplements to standardised specialist medical care versus standardised specialist medical care alone for patients with the chronic fatigue syndrome/myalgic encephalomyelitis or encephalopathy

    Directory of Open Access Journals (Sweden)

    DeCesare Julia C

    2007-03-01

    Full Text Available Abstract Background Chronic fatigue syndrome (CFS, also called myalgic encephalomyelitis/encephalopathy or ME is a debilitating condition with no known cause or cure. Improvement may occur with medical care and additional therapies of pacing, cognitive behavioural therapy and graded exercise therapy. The latter two therapies have been found to be efficacious in small trials, but patient organisations' surveys have reported adverse effects. Although pacing has been advocated by patient organisations, it lacks empirical support. Specialist medical care is commonly provided but its efficacy when given alone is not established. This trial compares the efficacy of the additional therapies when added to specialist medical care against specialist medical care alone. Methods/Design 600 patients, who meet operationalised diagnostic criteria for CFS, will be recruited from secondary care into a randomised trial of four treatments, stratified by current comorbid depressive episode and different CFS/ME criteria. The four treatments are standardised specialist medical care either given alone, or with adaptive pacing therapy or cognitive behaviour therapy or graded exercise therapy. Supplementary therapies will involve fourteen sessions over 23 weeks and a 'booster session' at 36 weeks. Outcome will be assessed at 12, 24, and 52 weeks after randomisation. Two primary outcomes of self-rated fatigue and physical function will assess differential effects of each treatment on these measures. Secondary outcomes include adverse events and reactions, subjective measures of symptoms, mood, sleep and function and objective measures of physical activity, fitness, cost-effectiveness and cost-utility. The primary analysis will be based on intention to treat and will use logistic regression models to compare treatments. Secondary outcomes will be analysed by repeated measures analysis of variance with a linear mixed model. All analyses will allow for stratification

  20. Infrared-based blink-detecting glasses for facial pacing: toward a bionic blink.

    Science.gov (United States)

    Frigerio, Alice; Hadlock, Tessa A; Murray, Elizabeth H; Heaton, James T

    2014-01-01

    IMPORTANCE Facial paralysis remains one of the most challenging conditions to effectively manage, often causing life-altering deficits in both function and appearance. Facial rehabilitation via pacing and robotic technology has great yet unmet potential. A critical first step toward reanimating symmetrical facial movement in cases of unilateral paralysis is the detection of healthy movement to use as a trigger for stimulated movement. OBJECTIVE To test a blink detection system that can be attached to standard eyeglasses and used as part of a closed-loop facial pacing system. DESIGN, SETTING, AND PARTICIPANTS Standard safety glasses were equipped with an infrared (IR) emitter-detector unit, oriented horizontally across the palpebral fissure, creating a monitored IR beam that became interrupted when the eyelids closed, and were tested in 24 healthy volunteers from a tertiary care facial nerve center community. MAIN OUTCOMES AND MEASURES Video-quantified blinking was compared with both IR sensor signal magnitude and rate of change in healthy participants with their gaze in repose, while they shifted their gaze from central to far-peripheral positions, and during the production of particular facial expressions. RESULTS Blink detection based on signal magnitude achieved 100% sensitivity in forward gaze but generated false detections on downward gaze. Calculations of peak rate of signal change (first derivative) typically distinguished blinks from gaze-related eyelid movements. During forward gaze, 87% of detected blink events were true positives, 11% were false positives, and 2% were false negatives. Of the 11% false positives, 6% were associated with partial eyelid closures. During gaze changes, false blink detection occurred 6% of the time during lateral eye movements, 10% of the time during upward movements, 47% of the time during downward movements, and 6% of the time for movements from an upward or downward gaze back to the primary gaze. Facial expressions

  1. The effect of different atrial pacing site and frequency in preventing postoperative atrial fibrillation in patients with sick sinus syndrome%不同心房起搏部位及频率对病态窦房结综合征患者术后房颤发生的影响

    Institute of Scientific and Technical Information of China (English)

    汪贵忠; 徐健

    2014-01-01

    Objective To evaluate the short-term effect of low atrial septum pacing and different pacing frequency to prevent atrial fibrillation in patients with sick sinus syndrome . The electrophysiological mechanism would be ana-lyzed. Methods Thirty eight sick sinus syndrome patients were randomly divided to right atrial appendage pacing group and low atrial septum pacing group. The conduction time from P wave to left atrial and left atrioventricular in-terval was measured at different atrial pacing frequency. The effects of different atrial pacing frequency on interatrial conduction time were analyzed. The occurrence of atrial fibrillation was compared within an average one year follow-up period. Results ①There were no differences in basic information before treatment between the two groups. ②There were no complication, pacing and sensing dysfunction between the two groups.③The occurrence of atrial fi-brillation in low atrial septal group was lower than that in right atrial appendage pacing group. Similarly, the con-duction time from P wave to left atrial was shorter and left atrioventricular conduction time was longer in low atrial septal group. The difference was statistically significant.④ Left atrioventricular interval was longer in high pacing frequency(80 bpm) compared to low pacing frequency(60 bpm) between the two groups. The difference was statis-tically significant. Conclusion In sick sinus syndrome patients, the occurrence of atrial fibrillation is lower on low-er atrial septal group. Increasing atrial pacing percentage may be enhanced the effect. The mechanism may be asso-ciated with shortened interatrial conduction and extended left atrioventricular interval, which improves interatrial and left atrioventricular synchrony eventually.%目的:探讨低位房间隔起搏及不同起搏频率对病态窦房结综合征患者术后房颤的短期影响,分析其电生理机制。方法38例病态窦房结综合征患者随机将心房电极植入

  2. A Near-Optimal Scheme for TCP ACK Pacing to Maintain Throughput in Wireless Networks

    CERN Document Server

    Bhutani, Gitanjali

    2009-01-01

    The advent of fourth generation technologies in wireless networks and the rapid growth of 3G have heralded an era that will require researchers to find reliable and easily implement-able solutions to the problem of poor TCP performance in the wireless environment. Since a large part of the Internet is TCP-based, solving this problem will be instrumental in determining if the move from wired to wireless will be seamless or not. This paper proposes a scheme that uses the base station's ability to predict the time at which the link may be going down and to estimate the period for which the mobile would be unreachable due to conditions like fading. By using cross-layer and ACK pacing algorithms, the base station prevents the fixed host from timing out while waiting for ACKs from the mobile. This in turn prevents TCP on the fixed host from bringing down the throughput drastically due to temporary network conditions, caused by mobility or the unreliability of wireless links. Experimental results indicate a reasonab...

  3. Analysis of a Student-Centered, Self-Paced Pedagogy Style for Teaching Information Systems Courses

    Directory of Open Access Journals (Sweden)

    Sharon Paranto

    2006-12-01

    Full Text Available The entry-level skills for students enrolling in a college-level information systems course can vary widely. This paper analyzes the impact of a "student-centered" pedagogy model, in which students use a self-paced approach for learning the material in an introductory information systems course, with pre-assigned dates for lectures and for assignment/exam deadlines. This new paradigm was implemented in several sections of an introductory information systems course over a two-semester time span. Under the new model, tutorial-style textbooks were used to help students master the material, all other materials were available online, and all exams were given using a hands-on, task-oriented online testing package, which included a multiple-choice/true-false component to test student understanding of the conceptual portion of the course. An anonymous student survey was used to gain student perceptions of the level of learning that took place under the new paradigm, as well as to measure student satisfaction with the course design, and a pre-/post-test was used to provide a measure of student learning.

  4. Optimal Pacing for Running 400 m and 800 m Track Races

    CERN Document Server

    Reardon, James C

    2012-01-01

    Physicists seeking to understand complex biological systems often find it rewarding to create simple "toy models" that reproduce system behavior. Here a toy model is used to understand a puzzling phenomenon from the sport of track and field. Races are almost always won, and records set, in 400 m and 800 m running events by people who run the first half of the race faster than the second half, which is not true of shorter races, nor of longer. There is general agreement that performance in the 400 m and 800 m is limited somehow by the amount of anaerobic metabolism that can be tolerated in the working muscles in the legs. A toy model of anaerobic metabolism is presented, from which an optimal pacing strategy is analytically calculated via the Euler-Lagrange equation. This optimal strategy is then modified to account for the fact that the runner starts the race from rest; this modification is shown to result in the best possible outcome by use of an elementary variational technique that supplements what is foun...

  5. Distractor Effect of Auditory Rhythms on Self-Paced Tapping in Chimpanzees and Humans.

    Directory of Open Access Journals (Sweden)

    Yuko Hattori

    Full Text Available Humans tend to spontaneously align their movements in response to visual (e.g., swinging pendulum and auditory rhythms (e.g., hearing music while walking. Particularly in the case of the response to auditory rhythms, neuroscientific research has indicated that motor resources are also recruited while perceiving an auditory rhythm (or regular pulse, suggesting a tight link between the auditory and motor systems in the human brain. However, the evolutionary origin of spontaneous responses to auditory rhythms is unclear. Here, we report that chimpanzees and humans show a similar distractor effect in perceiving isochronous rhythms during rhythmic movement. We used isochronous auditory rhythms as distractor stimuli during self-paced alternate tapping of two keys of an electronic keyboard by humans and chimpanzees. When the tempo was similar to their spontaneous motor tempo, tapping onset was influenced by intermittent entrainment to auditory rhythms. Although this effect itself is not an advanced rhythmic ability such as dancing or singing, our results suggest that, to some extent, the biological foundation for spontaneous responses to auditory rhythms was already deeply rooted in the common ancestor of chimpanzees and humans, 6 million years ago. This also suggests the possibility of a common attentional mechanism, as proposed by the dynamic attending theory, underlying the effect of perceiving external rhythms on motor movement.

  6. Mechanisms underlying syntactic comprehension deficits in vascular aphasia: new evidence from self-paced listening.

    Science.gov (United States)

    Caplan, David; Michaud, Jennifer; Hufford, Rebecca

    2015-01-01

    Sixty-one people with aphasia (pwa) and 41 matched controls were tested for the ability to understand sentences that required the ability to process particular syntactic elements and assign particular syntactic structures. Participants paced themselves word-by-word through 20 examples of 11 spoken sentence types and indicated which of two pictures corresponded to the meaning of each sentence. Sentences were developed in pairs such that comprehension of the experimental version of a pair required an aspect of syntactic processing not required in the corresponding baseline sentence. The need for the syntactic operations required only in the experimental version was triggered at a "critical word" in the experimental sentence. Listening times for critical words in experimental sentences were compared to those for corresponding words in the corresponding baseline sentences. The results were consistent with several models of syntactic comprehension deficits in pwa: resource reduction, slowed lexical and/or syntactic processing, abnormal susceptibility to interference from thematic roles generated non-syntactically. They suggest that a previously unidentified disturbance limiting the duration of parsing and interpretation may lead to these deficits, and that this mechanism may lead to structure-specific deficits in pwa. The results thus point to more than one mechanism underlying syntactic comprehension disorders both across and within pwa. PMID:26165856

  7. Performance on paced serial addition tasks indicates an associative network for calculation.

    Science.gov (United States)

    Hiscock, M; Caroselli, J S; Kimball, L E; Panwar, N

    2001-06-01

    Although paced serial addition (PSA) tasks are considered to be tests of general information-processing capacity, recent work suggests that performance on such tasks is influenced by arithmetic-specific variables. We designed two visual PSA experiments to determine whether the performance of normal adults would support predictions derived from the cognitive psychology of calculation. Experiment 1 showed that mixing familiar (Arabic numeral) and less familiar (Roman numeral) stimulus formats reduced scores below the averaged scores for pure Arabic and Roman lists. The Roman-Arabic order of addends was more difficult than the Arabic-Roman order. Experiment 2, which involved only Arabic numerals as addends, showed that performance could be impaired by constraining the trial-to-trial variability of sums. The results of both experiments confirm the importance of arithmetic-specific variables in PSA and provide support for an associative network model of calculation. In addition, the findings implicate interference from extraneous addends and responses as the performance-limiting factor. PMID:11404809

  8. Lower head temperature does not affect children's self-paced running velocity.

    Science.gov (United States)

    Ferreira Júnior, João; Martini, Angelo; Borba, Diego; Gomes, Leonardo; Pinto, João; Oliveira, Bernardo; Coelho, Daniel; Prado, Luciano; Rodrigues, Luiz

    2013-02-01

    To test if the use of a peaked cap protects children against sun radiation, allowing increased exercise performance, nineteen healthy children (10.3 ± 0.8 years old, 146.2 ± 6.9 cm, 36.8 ± 5.5 kg, 1.2 ± 0.1 m2 and 44.1 ± 2.8 mL.kg-1.min-1) took part in 4 experimental situations: 2 initial familiarization runs and 2 self-paced 6km runs (4 × 1.5 km exercise bouts with 3min rest intervals) one of them wearing a peaked cap (CAP) and another situation without the cap (NOCAP). The CAP and NOCAP situations were randomized. Exercise was performed outdoors 3-7 days apart. Environmental variables were measured every 10min, and physiological variables were measured before and after each run and during the rest intervals. Running velocity did not differ between CAP and NOCAP situations. The mean head temperature was reduced by 1.1 °C in the CAP situation (p temperature, mean heart rate, rate of perceived exertion and wet bulb and globe temperature did not differ between CAP and NOCAP. The decrease in the mean head temperature was not sufficient to alter running velocity. PMID:23406699

  9. Distractor Effect of Auditory Rhythms on Self-Paced Tapping in Chimpanzees and Humans.

    Science.gov (United States)

    Hattori, Yuko; Tomonaga, Masaki; Matsuzawa, Tetsuro

    2015-01-01

    Humans tend to spontaneously align their movements in response to visual (e.g., swinging pendulum) and auditory rhythms (e.g., hearing music while walking). Particularly in the case of the response to auditory rhythms, neuroscientific research has indicated that motor resources are also recruited while perceiving an auditory rhythm (or regular pulse), suggesting a tight link between the auditory and motor systems in the human brain. However, the evolutionary origin of spontaneous responses to auditory rhythms is unclear. Here, we report that chimpanzees and humans show a similar distractor effect in perceiving isochronous rhythms during rhythmic movement. We used isochronous auditory rhythms as distractor stimuli during self-paced alternate tapping of two keys of an electronic keyboard by humans and chimpanzees. When the tempo was similar to their spontaneous motor tempo, tapping onset was influenced by intermittent entrainment to auditory rhythms. Although this effect itself is not an advanced rhythmic ability such as dancing or singing, our results suggest that, to some extent, the biological foundation for spontaneous responses to auditory rhythms was already deeply rooted in the common ancestor of chimpanzees and humans, 6 million years ago. This also suggests the possibility of a common attentional mechanism, as proposed by the dynamic attending theory, underlying the effect of perceiving external rhythms on motor movement. PMID:26132703

  10. Potentiation and Electrical Stimulus Frequency During Self-Paced Exercise and Recovery

    Directory of Open Access Journals (Sweden)

    Froyd Christian

    2014-10-01

    Full Text Available The aim of this study was to investigate the effect of potentiation on stimulation-induced muscle function during and after an intense bout of self-paced dynamic exercise. Ten active subjects performed a time trial involving repetitive concentric extension-flexion of the right knee using a Biodex dynamometer. Electrical stimulation before and after a 5 s maximal isometric voluntary contraction was performed before the start of the time trial and immediately (< 5 s after each 20% of the time trial as well as 1, 2, 4 and 8 min after time trial termination. Potentiation was observed before the time trial and as early as 1-2 min after the time trial, but no potentiation was detected during or immediately after the time trial for neither single or paired stimuli. At termination of the time trial, “potentiated” peak torque was significantly more reduced than “unpotentiated" peak torque for single stimulus (-65 ± 10% and -42 ± 18%, respectively and paired stimuli at 100 Hz (-51 ± 10% and -33 ± 15%, respectively. Faster recovery for “potentiated” compared to “unpotentiated” peak torque indicate that potentiate peak torque measurements or delay the post-exercise measurements more than a few seconds, will underestimate peripheral fatigue. In conclusion, the potentiation after maximal contraction disappears during intense exercise. Whether the muscle is already potentiated during intense contraction or fatiguing mechanisms inhibits potentiation remains to be clarified

  11. Divertor load footprint of ELMs in pellet triggering and pacing experiments at JET

    Energy Technology Data Exchange (ETDEWEB)

    Frigione, D., E-mail: domenico.frigione@frascati.enea.it [Unità Tecnica Fusione, ENEA C.R. Frascati, via E. Fermi 45, 00044 Frascati (Roma) (Italy); Garzotti, L. [CCFE, Culham Science Centre, OX14 3DB (United Kingdom); Lennholm, M. [EFDA CSU, Culham Science Centre, OX14 3DB (United Kingdom); Alper, B. [CCFE, Culham Science Centre, OX14 3DB (United Kingdom); Artaserse, G. [Unità Tecnica Fusione, ENEA C.R. Frascati, via E. Fermi 45, 00044 Frascati (Roma) (Italy); Bennett, P. [CCFE, Culham Science Centre, OX14 3DB (United Kingdom); Giovannozzi, E. [Unità Tecnica Fusione, ENEA C.R. Frascati, via E. Fermi 45, 00044 Frascati (Roma) (Italy); Eich, T. [Max Planck Institute for Plasma Physics, Garching (Germany); Kocsis, G. [WIGNER RCP RMI, POB 49, 1525 Budapest (Hungary); Lang, P.T. [Max Planck Institute for Plasma Physics, Garching (Germany); Maddaluno, G. [Unità Tecnica Fusione, ENEA C.R. Frascati, via E. Fermi 45, 00044 Frascati (Roma) (Italy); Mooney, R. [CCFE, Culham Science Centre, OX14 3DB (United Kingdom); Rack, M. [Institut für Energieforschung – Plasmaphysik, Forschungszentrum Jülich, 52425 Jülich (Germany); Sips, G. [EFDA CSU, Culham Science Centre, OX14 3DB (United Kingdom); Tvalashvili, G. [CCFE, Culham Science Centre, OX14 3DB (United Kingdom); Viola, B. [Unità Tecnica Fusione, ENEA C.R. Frascati, via E. Fermi 45, 00044 Frascati (Roma) (Italy); Wilkes, D. [CCFE, Culham Science Centre, OX14 3DB (United Kingdom)

    2015-08-15

    An investigation of pellet pacing and triggering of Edge Localized Modes (ELMs) was carried out in the frame of ELM mitigation studies aimed at reducing their damaging effects on the plasma-facing components (PFCs). The divertor power load footprint of triggered ELMs was compared with gas puffing controlled ELMs. Small pellets, corresponding to a few per cent of the target plasma particle inventory, were used to minimize the fueling effect and the total particle throughput. There is no evidence that pellets can reduce the divertor power load with respect to gas fueling when operating at the same ELM frequency. The line average density and the energy confinement time remained constant when the gas was progressively substituted by pellets. The launch from the Vertical High Field Side (VHFS) confirmed to be more efficient in ELM triggering than from the Low Field Side (LFS) while the power load footprint remained the same both in time evolution and in spatial distribution when changing the injection geometry.

  12. Positive pacing strategies are utilised by elite male and female para-cyclists in short time trials in the velodrome

    Directory of Open Access Journals (Sweden)

    Rachel Lindsey Wright

    2016-01-01

    Full Text Available In para-cycling, competitors are classed based on functional impairment resulting in cyclists with neurological and locomotor impairments competing against each other. In Paralympic competition, classes are combined by using a factoring adjustment to race times to produce the overall medallists. Pacing in short-duration track cycling events is proposed to utilise an all-out strategy in able-bodied competition. However, pacing in para-cycling may vary depending on the level of impairment. Analysis of the pacing strategies employed by different classification groups may offer scope for optimal performance; therefore, this study investigated the pacing strategy adopted during the 1-km time trial (TT and 500-m TT in elite C1 to C3 para-cyclists and able-bodied cyclists. Total times and intermediate split times (125-m intervals; measured to 0.001s were obtained from the C1-C3 men’s 1-km TT (n=28 and women’s 500-m TT (n=9 from the 2012 Paralympic Games and the men’s 1-km TT (n=19 and women’s 500-m TT (n=12 from the 2013 UCI World Track Championships from publically available video. Split times were expressed as actual time, factored time (for the para-cyclists and as a percentage of total time. A two-way analysis of variance was used to investigate differences in split times between the different classifications and the able-bodied cyclists in the men’s 1-km TT and between the para-cyclists and able-bodied cyclists in the women’s 500-m TT. The importance of position at the first split was investigated with Kendall’s Tau-b correlation. The first 125-m split time was the slowest for all cyclists, representing the acceleration phase from a standing start. C2 cyclists were slowest at this 125-m split, probably due to a combination of remaining seated in this acceleration phase and a high proportion of cyclists in this group being trans-femoral amputees. Not all cyclists used aero-bars, preferring to use drop, flat or bullhorn handlebars

  13. Modeling Floodplain Dynamics: Can the Ganges-Brahmaputra Delta keep pace with 21st Century Sea Level Rise?

    Science.gov (United States)

    Rogers, K. G.; Overeem, I.

    2013-12-01

    The low-lying Ganges-Brahmaputra (G-B) Delta in Bangladesh is densely populated (~1200 people/km2) and could be flooded within the next century by rapid sea level rise and increased monsoonal rains. The G-B Rivers currently transport 1*109 tons of sediment from their basins in the Himalaya Mountains to the delta each year, with ~90% of the annual sediment load delivered during the Asian summer monsoon. Sediment distribution across the delta's surface by floods and coastal storms has kept pace with the rate of relative sea level rise along the Bengal coast, enabling the delta to maintain a positive elevation. However, ensemble Community Climate System Model experiments predict 11% higher monsoonal rainfall for the next century, potentially leading to extreme flooding events in the delta. Stratigraphic reconstructions show that sedimentation in the upper G-B floodplain was more than doubled under the Early Holocene enhanced monsoonal regime, suggesting that the delta may withstand an increase in monsoon intensity, flooding, and tropical cyclones that are currently predicted. Whether the G-B floodplains and coastal areas will ultimately drown under predicted sea level rise and monsoon intensification depends on a balance of aggradation, eustatic sea level rise and subsidence. To improve predictions of climatic forcing on aggradation rates in the lower G-B floodplain and coastal plain, direct sedimentation measurements collected in 2008 and 2012 in the lower delta are paired with a series of model components coupled within the Community Surface Dynamics Modeling System (CSDMS) Modeling Tool (CMT). We use three separate numerical models to simulate river basin sediment flux, floodplain sedimentation, and tidal-plain aggradation. The model inputs are based on available 20Th century climate and river gauge data, and outputs are compared to modern sedimentation rates within the G-B tidal delta and highly cultivated central coastal plain. The models are then used to test

  14. Synchronized personalized music audio-playlists to improve adherence to physical activity among patients participating in a structured exercise program: a proof-of-principle feasibility study

    OpenAIRE

    Alter, David A.; O’Sullivan, Mary; Oh, Paul I.; Redelmeier, Donald A.; Marzolini, Susan; Liu, Richard; Forhan, Mary; Silver, Michael; Goodman, Jack M.; Bartel, Lee R

    2015-01-01

    Background Preference-based tempo-pace synchronized music has been shown to reduce perceived physical activity exertion and improve exercise performance. The extent to which such strategies can improve adherence to physical activity remains unknown. The objective of the study is to explore the feasibility and efficacy of tempo-pace synchronized preference-based music audio-playlists on adherence to physical activity among cardiovascular disease patients participating in a cardiac rehabilitati...

  15. Sixteen failures in a single model of bipolar polyurethane-insulated ventricular pacing lead: a 44-month experience.

    Science.gov (United States)

    Hanson, J S

    1984-05-01

    During a 44-month period, 105 Medtronic model 6972-58 polyurethane-insulated, bipolar ventricular pacing leads were implanted, of which 16 failed clinically at a mean of 20.5 months post-implant. Pacing dysfunction presented as either intermittent or complete loss of sensing and/or capture and, rarely, oversensing . Thirteen of the 16 patients were asymptomatic, and problems were detected in 11 instances during routine telephonic surveillance. At the time of lead replacement, low or widely fluctuating lead resistance values and high current drain were uniformly observed. The single lead capable of total extraction revealed rupture of both internal and external insulation. A brief summary of the currently much-discussed "polyurethane controversy" is presented, and the issue of patient management is discussed. PMID:6204292

  16. Comparison of the Event-Related Desynchronization during Self-Paced Movement and when playing a Nintendo Wii Game

    Directory of Open Access Journals (Sweden)

    Nikola Šobajić

    2011-06-01

    Full Text Available We compared pre-movement event-related desynchronization (ERD of μ rhythm over the primary motor cortex using surface electrodes in a group of five healthy subjects during self-paced wrist movement and the wrist movement when playing a Nintendo Wii. We present a method that uses ERD to detect the onset of movement in single-trial electroencephalographic (EEG data. This algorithm produced a mean detection accuracy of 83% for the self-paced movement and 75% for the Wii-included sessions, without requiring subject training. This technique can be employed in an EEG-based brain–computer interface due to its high recognition rate and simplicity in computation.

  17. Engaging nursing homes (NHs) in the PACE study:comparing recruitment in observational and intervention research designs

    OpenAIRE

    Collingridge Moore, Danielle

    2016-01-01

    Background: NH residents are often excluded from epidemiological studies, demonstrating a need for representative, internationally comparable research in this area. Data on palliative care provided by NHs is reported to the Care Quality Commission in England, but the quality of care is often locally determined. Aims: To review the challenges encountered in engaging and recruiting NHs across England to the European Commission funded PACE research project; a two part study comprising of a retro...

  18. Properties of PACE-I HgCdTe Detectors in Space - the NICMOS Warm-up Monitoring Program

    OpenAIRE

    Boeker, T.

    2000-01-01

    We summarize the results of a monitoring program which was executed following the cryogen exhaustion of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) onboard the Hubble Space Telescope. During the subsequent warm-up, detector parameters such as detective quantum efficiency, dark current, bias offsets, and saturation levels have been measured over the temperature range 62K to about 100K. The measurements provide a unique database of the characteristics of PACE-I HgCdTe detect...

  19. Comparison between end-tidal CO2 and respiration volume per time for detecting BOLD signal fluctuations during paced hyperventilation

    OpenAIRE

    Vogt, Keith M.; Ibinson, James W; Schmalbrock, Petra; Small, Robert H

    2011-01-01

    Respiratory motion and capnometry monitoring were performed during blood oxygen level dependent (BOLD) functional magnetic resonance imaging (FMRI) of the brain while a series of paced hyperventilation tasks were performed that caused significant hypocapnia. Respiration volume per time (RVT) and end-tidal carbon dioxide (ETCO2) were determined and compared for their ability to explain BOLD contrast changes in the data. A 35% decrease in ETCO2 was observed along with corresponding changes in R...

  20. IMPLEMENTATION OF BIOFEEDBACK IN A CLOSED LOOP OF HEART RATE VARIABILITY AND PACED BREATHING IN PATIENTS WITH ARTERIAL HYPERTENSION

    OpenAIRE

    Kulik, O.; Schmidt, O; BELAL S. A. S.; Rank, I.

    2014-01-01

    The effectiveness of biofeedback in a closed loop of heart rate variability (HRV) and paced breathing in patients with arterial hypertension was studied. 61 subjects with arterial hypertension (31 females and 30 males, mean age 56.8 ± 6.2 years) were examined. In accordance with the objective of the study all subjects were divided into 2 groups: 1 biofeedback group (34 subjects) and 2 the comparison group (27 subjects). 5 biofeedback sessions were performed in biofeedback group. In the compar...

  1. Through the looking glass :a semiotic analysis and experimental test of pace and angle effects in television advertising

    OpenAIRE

    Larsen, Val

    1995-01-01

    This dissertation addressed two broad questions: a) is it possible to systematically describe dimensions of form on which montage varies in TV advertising, and b) given that dimensions can be identified, how do variations in form affect viewer responses to ads? The first question was addressed through a semiotic analysis of ad form, the second question through an experiment that tested for pace and angle effects on brand learning and brand attitudes. The semiotic a...

  2. Therapeutic efficacy of digital music gastric electrical pacing for refractory functional dyspepsia concomitant with non-erosive reflux disease

    OpenAIRE

    Ya-mei RAN; Lin, Ling; Yu-qin HE; Chen, Qiang; Ji, Lei; Xiu-qiong LANG; Huang, Zhi-yong; YANG, MIN

    2015-01-01

    Objective To study the clinical efficacy of digital music gastric electrical pacing for refractory functional dyspepsia concomitant with non-erosive reflux disease, and its effects on mental health and life-quality of the patients. Methods According to the Rome Ⅲ criteria and Montreal consensus in diagnosis of gastroesophageal reflux disease, 50 patients with concomitant refractory functional dyspepsia and non-erosive reflux disease were recruited. The clinical efficacy of digital music gastr...

  3. Pacing-Induced Non-Uniform Ca2+ Dynamics in Rat Atria Revealed by Rapid-Scanning Confocal Microscopy

    International Nuclear Information System (INIS)

    Intracellular Ca2+ ([Ca2+]i) dynamics in isolated myocytes differ between the atria and ventricles due to the distinct t-tubular distributions. Although cellular aspects of ventricular [Ca2+]i dynamics in the heart have been extensively studied, little is known about those of atrial myocytes in situ. Here we visualized precise [Ca2+]i dynamics of atrial myocytes in Langendorff-perfused rat hearts by rapid-scanning confocal microscopy. Of 16 fluo-4-loaded hearts imaged during pacing up to 4-Hz, five hearts showed spatially uniform Ca2+ transients on systole among individual cells, whereas no discernible [Ca2+]i elevation developed during diastole. In contrast, the remaining hearts showed non-uniform [Ca2+]i dynamics within and among the cells especially under high-frequency (4 Hz) excitation, where subcellular cluster-like [Ca2+]i rises or wave-like [Ca2+]i propagation occurred on excitation. Such [Ca2+]i inhomogeneity was more pronounced at high-frequency pacing, showing beat-to-beat Ca2+ transient alternans. Despite such non-uniform dynamics, cessation of burst pacing of the atria was not followed by emergence of spontaneous Ca2+ waves, indicating minor Ca2+-releasing potentials of the sarcoplasmic reticulum (SR). In summary, rat atria display a propensity to show non-uniform [Ca2+]i dynamics on systole due to impaired Ca2+-release from the SR and paucity of t-tubules. Our results provide an important basis for understanding atrial pathophysiology

  4. Effects of musical tempo on physiological, affective, and perceptual variables and performance of self-selected walking pace.

    Science.gov (United States)

    Almeida, Flávia Angélica Martins; Nunes, Renan Felipe Hartmann; Ferreira, Sandro Dos Santos; Krinski, Kleverton; Elsangedy, Hassan Mohamed; Buzzachera, Cosme Franklin; Alves, Ragami Chaves; Gregorio da Silva, Sergio

    2015-06-01

    [Purpose] This study investigated the effects of musical tempo on physiological, affective, and perceptual responses as well as the performance of self-selected walking pace. [Subjects] The study included 28 adult women between 29 and 51 years old. [Methods] The subjects were divided into three groups: no musical stimulation group (control), and 90 and 140 beats per minute musical tempo groups. Each subject underwent three experimental sessions: involved familiarization with the equipment, an incremental test to exhaustion, and a 30-min walk on a treadmill at a self-selected pace, respectively. During the self-selected walking session, physiological, perceptual, and affective variables were evaluated, and walking performance was evaluated at the end. [Results] There were no significant differences in physiological variables or affective response among groups. However, there were significant differences in perceptual response and walking performance among groups. [Conclusion] Fast music (140 beats per minute) promotes a higher rating of perceived exertion and greater performance in self-selected walking pace without significantly altering physiological variables or affective response. PMID:26180303

  5. Muscle-Type Specific Autophosphorylation of CaMKII Isoforms after Paced Contractions

    Directory of Open Access Journals (Sweden)

    Wouter Eilers

    2014-01-01

    Full Text Available We explored to what extent isoforms of the regulator of excitation-contraction and excitation-transcription coupling, calcium/calmodulin protein kinase II (CaMKII contribute to the specificity of myocellular calcium sensing between muscle types and whether concentration transients in its autophosphorylation can be simulated. CaMKII autophosphorylation at Thr287 was assessed in three muscle compartments of the rat after slow or fast motor unit-type stimulation and was compared against a computational model (CaMuZclE coupling myocellular calcium dynamics with CaMKII Thr287 phosphorylation. Qualitative differences existed between fast- (gastrocnemius medialis and slow-type muscle (soleus for the expression pattern of CaMKII isoforms. Phospho-Thr287 content of δA CaMKII, associated with nuclear functions, demonstrated a transient and compartment-specific increase after excitation, which contrasted to the delayed autophosphorylation of the sarcoplasmic reticulum-associated βM CaMKII. In soleus muscle, excitation-induced δA CaMKII autophosphorylation demonstrated frequency dependence (P = 0.02. In the glycolytic compartment of gastrocnemius medialis, CaMKII autophosphorylation after excitation was blunted. In silico assessment emphasized the importance of mitochondrial calcium buffer capacity for excitation-induced CaMKII autophosphorylation but did not predict its isoform specificity. The findings expose that CaMKII autophosphorylation with paced contractions is regulated in an isoform and muscle type-specific fashion and highlight properties emerging for phenotype-specific regulation of CaMKII.

  6. In-Bed Accountability Development for a Passively Cooled, Electrically Heated Hydride (PACE) Bed

    International Nuclear Information System (INIS)

    A nominal 1500 STP-L PAssively Cooled, Electrically heated hydride (PACE) Bed has been developed for implementation into a new Savannah River Site tritium project. The 1.2 meter (four-foot) long process vessel contains on internal 'U-tube' for tritium In-Bed Accountability (IBA) measurements. IBA will be performed on six, 12.6 kg production metal hydride storage beds.IBA tests were done on a prototype bed using electric heaters to simulate the radiolytic decay of tritium. Tests had gas flows from 10 to 100 SLPM through the U-tube or 100 SLPM through the bed's vacuum jacket. IBA inventory measurement errors at the 95% confidence level were calculated using the correlation of IBA gas temperature rise, or (hydride) bed temperature rise above ambient temperature, versus simulated tritium inventory.Prototype bed IBA inventory errors at 100 SLPM were the largest for gas flows through the vacuum jacket: 15.2 grams for the bed temperature rise and 11.5 grams for the gas temperature rise. For a 100 SLPM U-tube flow, the inventory error was 2.5 grams using bed temperature rise and 1.6 grams using gas temperature rise. For 50 to 100 SLPM U-tube flows, the IBA gas temperature rise inventory errors were nominally one to two grams that increased above four grams for flows less than 50 SLPM. For 50 to 100 SLPM U-tube flows, the IBA bed temperature rise inventory errors were greater than the gas temperature rise errors, but similar errors were found for both methods at gas flows of 20, 30, and 40 SLPM.Electric heater IBA tests were done for six production hydride beds using a 45 SLPM U-tube gas flow. Of the duplicate runs performed on these beds, five of the six beds produced IBA inventory errors of approximately three grams: consistent with results obtained in the laboratory prototype tests

  7. Keeping Pace with Your Eating: Visual Feedback Affects Eating Rate in Humans

    Science.gov (United States)

    Bosworth, Matthew L.; Godinot, Nicolas; Martin, Nathalie; Rogers, Peter J.; Brunstrom, Jeffrey M.

    2016-01-01

    Deliberately eating at a slower pace promotes satiation and eating quickly has been associated with a higher body mass index. Therefore, understanding factors that affect eating rate should be given high priority. Eating rate is affected by the physical/textural properties of a food, by motivational state, and by portion size and palatability. This study explored the prospect that eating rate is also influenced by a hitherto unexplored cognitive process that uses ongoing perceptual estimates of the volume of food remaining in a container to adjust intake during a meal. A 2 (amount seen; 300ml or 500ml) x 2 (amount eaten; 300ml or 500ml) between-subjects design was employed (10 participants in each condition). In two ‘congruent’ conditions, the same amount was seen at the outset and then subsequently consumed (300ml or 500ml). To dissociate visual feedback of portion size and actual amount consumed, food was covertly added or removed from a bowl using a peristaltic pump. This created two additional ‘incongruent’ conditions, in which 300ml was seen but 500ml was eaten or vice versa. We repeated these conditions using a savoury soup and a sweet dessert. Eating rate (ml per second) was assessed during lunch. After lunch we assessed fullness over a 60-minute period. In the congruent conditions, eating rate was unaffected by the actual volume of food that was consumed (300ml or 500ml). By contrast, we observed a marked difference across the incongruent conditions. Specifically, participants who saw 300ml but actually consumed 500ml ate at a faster rate than participants who saw 500ml but actually consumed 300ml. Participants were unaware that their portion size had been manipulated. Nevertheless, when it disappeared faster or slower than anticipated they adjusted their rate of eating accordingly. This suggests that the control of eating rate involves visual feedback and is not a simple reflexive response to orosensory stimulation. PMID:26828922

  8. Single trial prediction of self-paced reaching directions from EEG signals

    Directory of Open Access Journals (Sweden)

    Eileen Yi Lee Lew

    2014-08-01

    Full Text Available Early detection of movement intention could possibly minimize the delays in the activation of neuroprosthetic devices. As yet, single trial analysis using non-invasive approaches for understanding such movement preparation remains a challenging task. We studied the feasibility of predicting movement directions in self-paced upper limb center-out reaching tasks, i.e., spontaneous movements executed without an external cue that can better reflect natural motor behavior in humans. We reported results of non-invasive electroencephalography (EEG recorded from mild stroke patients and able-bodied participants. Previous studies have shown that low frequency EEG oscillations are modulated by the intent to move and therefore, can be decoded prior to the movement execution. Motivated by these results, we investigated whether slow cortical potentials (SCPs preceding movement onset can be used to classify reaching directions and evaluated the performance using 5-fold cross-validation. For able-bodied subjects, we obtained an average decoding accuracy of 76% (chance level of 25% at 62.5ms before onset using the amplitude of on-going SCPs with above chance level performances between 875ms to 437.5ms prior to onset. The decoding accuracy for the stroke patients was on average 47% with their paretic arms. Comparison of the decoding accuracy across different frequency ranges (i.e., SCPs, delta, theta, alpha and gamma yielded the best accuracy using SCPs filtered between 0.1 to 1 Hz. Across all the subjects, including stroke subjects, the best selected features were obtained mostly from the fronto-parietal regions, hence consistent with previous neurophysiological studies on arm reaching tasks. In summary, we concluded that SCPs allow the possibility of single trial decoding of reaching directions at least 312.5ms before onset of reach.

  9. Automated Electrophysiology Makes the Pace for Cardiac Ion Channel Safety Screening

    Directory of Open Access Journals (Sweden)

    Clemens eMoeller

    2011-11-01

    Full Text Available The field of automated patch-clamp electrophysiology has emerged from the tension between the pharmaceutical industry’s need for high-throughput compound screening versus its need to be conservative due to regulatory requirements. On the one hand, hERG channel screening was increasingly requested for new chemical entities, as the correlation between blockade of the ion channel coded by hERG and Torsades de Pointes cardiac arrhythmia gained increasing attention. On the other hand, manual patch-clamping, typically quoted as the gold-standard for understanding ion channel function and modulation, was far too slow (and, consequently, too expensive for keeping pace with the numbers of compounds submitted for hERG channel investigations from pharmaceutical R&D departments. In consequence it became more common for some pharmaceutical companies to outsource safety pharmacological investigations, with a focus on hERG channel interactions. This outsourcing has allowed those pharmaceutical companies to build up operational flexibility and greater independence from internal resources, and allowed them to obtain access to the latest technological developments that emerged in automated patch-clamp electrophysiology – much of which arose in specialized biotech companies. Assays for nearly all major cardiac ion channels are now available by automated patch-clamping using heterologous expression systems, and recently, automated action potential recordings from stem-cell derived cardiomyocytes have been demonstrated. Today, most of the large pharmaceutical companies have acquired automated electrophysiology robots and have established various automated cardiac ion channel safety screening assays on these, in addition to outsourcing parts of their needs for safety screening.

  10. L-type calcium channels in adrenal chromaffin cells: role in pace-making and secretion.

    Science.gov (United States)

    Marcantoni, A; Baldelli, P; Hernandez-Guijo, J M; Comunanza, V; Carabelli, V; Carbone, E

    2007-01-01

    Voltage-gated L-type (Cav1.2 and Cav1.3) channels are widely expressed in cardiovascular tissues and represent the critical drug-target for the treatment of several cardiovascular diseases. The two isoforms are also abundantly expressed in neuronal and neuroendocrine tissues. In the brain, Cav1.2 and Cav1.3 channels control synaptic plasticity, somatic activity, neuronal differentiation and brain aging. In neuroendocrine cells, they are involved in the genesis of action potential generation, bursting activity and hormone secretion. Recent studies have shown that Cav1.2 and Cav1.3 are also expressed in chromaffin cells but their functional role has not yet been identified despite that L-type channels possess interesting characteristics, which confer them an important role in the control of catecholamine secretion during action potentials stimulation. In intact rat adrenal glands L-type channels are responsible for adrenaline and noradrenaline release following splanchnic nerve stimulation or nicotinic receptor activation. L-type channels can be either up- or down-modulated by membrane autoreceptors following distinct second messenger pathways. L-type channels are tightly coupled to BK channels and activate at relatively low-voltages. In this way they contribute to the action potential hyperpolarization and to the pace-maker current controlling action potential firings. L-type channels are shown also to regulate the fast secretion of the immediate readily releasable pool of vesicles with the same Ca(2+)-efficiency of other voltage-gated Ca(2+) channels. In mouse adrenal slices, repeated action potential-like stimulations drive L-type channels to a state of enhanced stimulus-secretion efficiency regulated by beta-adrenergic receptors. Here we will review all these novel findings and discuss the possible implication for a specific role of L-type channels in the control of chromaffin cells activity. PMID:17561252

  11. Periprocedural temporary pacing in primary percutaneous coronary intervention for patients with acute inferior myocardial infarction

    Directory of Open Access Journals (Sweden)

    Hwang YM

    2016-03-01

    Full Text Available You Mi Hwang,1 Chul-Min Kim,2 Keon-Woong Moon2 1Department of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 2Department of Internal Medicine, St Vincent’s Hospital, The Catholic University of Korea, Suwon, South KoreaObjective: High-degree atrioventricular block (AVB, including complete AVB in acute inferior ST-elevation myocardial infarction (STEMI, is not uncommon. However, there is no study evaluating the clinical differences between patients who have undergone temporary pacing (TP and patients who have not. The present study was designed to investigate whether TP has any prognostic significance in inferior STEMI complicated by complete AVB.Methods: From January 2009 to December 2014, 295 consecutive patients diagnosed with inferior wall STEMI in a university hospital were reviewed. All of them underwent primary percutaneous coronary intervention (PCI. Among the 295 patients, there were 72 patients with complete AVB. The clinical characteristics, procedural data, and long-term major adverse cardiocerebrovascular events were compared in patients with and without TP.Results: Baseline clinical and procedural characteristics were similar between patients with and without TP. Patients with TP were more likely to present with cardiogenic shock; thus, additional interventions were attempted via a femoral approach, as patients received further treatment with intra-aortic balloon pumps and were subjected to additional cardiopulmonary resuscitation. Most cases of complete AVB were primarily caused by right coronary artery occlusion. After a median follow-up period of 344 (range, 105.5–641 days, major adverse cardiocerebrovascular events did not differ between the groups (P=0.528.Conclusion: We conclude that primary PCI without TP is acceptable in complete AVB-complicated acute inferior STEMI. To avoid delay in reperfusion, we suggest that primary PCI should be the first priority therapy rather than treating

  12. Rationale and design for PACE: patients with intermittent claudication injected with ALDH bright cells.

    Science.gov (United States)

    Perin, Emerson C; Murphy, Michael; Cooke, John P; Moyé, Lem; Henry, Timothy D; Bettencourt, Judy; Gahremanpour, Amir; Leeper, Nicholas; Anderson, R David; Hiatt, William R; Lima, Joao A; Venkatesh, Bharath; Sayre, Shelly L; Vojvodic, Rachel W; Taylor, Doris A; Ebert, Ray F; Hirsch, Alan T

    2014-11-01

    Peripheral artery disease (PAD) is recognized as a public health issue because of its prevalence, functional limitations, and increased risk of systemic ischemic events. Current treatments for claudication, the primary symptom in patients with PAD, have limitations. Cells identified using cytosolic enzyme aldehyde dehydrogenase (ALDH) may benefit patients with severe PAD but has not been studied in patients with claudication. PACE is a randomized, double-blind, placebo-controlled clinical trial conducted by the Cardiovascular Cell Therapy Research Network to assess the safety and efficacy of autologous bone marrow-derived ALDH(br) cells delivered by direct intramuscular injections in 80 patients with symptom-limiting intermittent claudication. Eligible patients will have a significant stenosis or occlusion of infrainguinal arteries and a resting ankle-brachial index less than 0.90 and will be randomized 1:1 to cell or placebo treatment with a 1-year follow-up. The primary end points are the change in peak walking time and leg collateral arterial anatomy, calf muscle blood flow, and tissue perfusion as determined by magnetic resonance imaging at 6 months compared with baseline. The latter 3 measurements are new physiologic lower extremity tissue perfusion and PAD imaging-based end points that may help to quantify the biologic and mechanistic effects of cell therapy. This trial will collect important mechanistic and clinical information on the safety and efficacy of ALDH(br) cells in patients with claudication and provide valuable insight into the utility of advanced magnetic resonance imaging end points. PMID:25440794

  13. Keeping Pace with Your Eating: Visual Feedback Affects Eating Rate in Humans.

    Directory of Open Access Journals (Sweden)

    Laura L Wilkinson

    Full Text Available Deliberately eating at a slower pace promotes satiation and eating quickly has been associated with a higher body mass index. Therefore, understanding factors that affect eating rate should be given high priority. Eating rate is affected by the physical/textural properties of a food, by motivational state, and by portion size and palatability. This study explored the prospect that eating rate is also influenced by a hitherto unexplored cognitive process that uses ongoing perceptual estimates of the volume of food remaining in a container to adjust intake during a meal. A 2 (amount seen; 300 ml or 500 ml x 2 (amount eaten; 300 ml or 500 ml between-subjects design was employed (10 participants in each condition. In two 'congruent' conditions, the same amount was seen at the outset and then subsequently consumed (300 ml or 500 ml. To dissociate visual feedback of portion size and actual amount consumed, food was covertly added or removed from a bowl using a peristaltic pump. This created two additional 'incongruent' conditions, in which 300 ml was seen but 500 ml was eaten or vice versa. We repeated these conditions using a savoury soup and a sweet dessert. Eating rate (ml per second was assessed during lunch. After lunch we assessed fullness over a 60-minute period. In the congruent conditions, eating rate was unaffected by the actual volume of food that was consumed (300 ml or 500 ml. By contrast, we observed a marked difference across the incongruent conditions. Specifically, participants who saw 300 ml but actually consumed 500 ml ate at a faster rate than participants who saw 500 ml but actually consumed 300 ml. Participants were unaware that their portion size had been manipulated. Nevertheless, when it disappeared faster or slower than anticipated they adjusted their rate of eating accordingly. This suggests that the control of eating rate involves visual feedback and is not a simple reflexive response to orosensory stimulation.

  14. Keeping Pace with Your Eating: Visual Feedback Affects Eating Rate in Humans.

    Science.gov (United States)

    Wilkinson, Laura L; Ferriday, Danielle; Bosworth, Matthew L; Godinot, Nicolas; Martin, Nathalie; Rogers, Peter J; Brunstrom, Jeffrey M

    2016-01-01

    Deliberately eating at a slower pace promotes satiation and eating quickly has been associated with a higher body mass index. Therefore, understanding factors that affect eating rate should be given high priority. Eating rate is affected by the physical/textural properties of a food, by motivational state, and by portion size and palatability. This study explored the prospect that eating rate is also influenced by a hitherto unexplored cognitive process that uses ongoing perceptual estimates of the volume of food remaining in a container to adjust intake during a meal. A 2 (amount seen; 300 ml or 500 ml) x 2 (amount eaten; 300 ml or 500 ml) between-subjects design was employed (10 participants in each condition). In two 'congruent' conditions, the same amount was seen at the outset and then subsequently consumed (300 ml or 500 ml). To dissociate visual feedback of portion size and actual amount consumed, food was covertly added or removed from a bowl using a peristaltic pump. This created two additional 'incongruent' conditions, in which 300 ml was seen but 500 ml was eaten or vice versa. We repeated these conditions using a savoury soup and a sweet dessert. Eating rate (ml per second) was assessed during lunch. After lunch we assessed fullness over a 60-minute period. In the congruent conditions, eating rate was unaffected by the actual volume of food that was consumed (300 ml or 500 ml). By contrast, we observed a marked difference across the incongruent conditions. Specifically, participants who saw 300 ml but actually consumed 500 ml ate at a faster rate than participants who saw 500 ml but actually consumed 300 ml. Participants were unaware that their portion size had been manipulated. Nevertheless, when it disappeared faster or slower than anticipated they adjusted their rate of eating accordingly. This suggests that the control of eating rate involves visual feedback and is not a simple reflexive response to orosensory stimulation. PMID:26828922

  15. Probucol attenuates atrial autonomic remodeling in a canine model of atrial fibrillation produced by prolonged atrial pacing

    Institute of Scientific and Technical Information of China (English)

    GONG Yong-tai; LI Wei-min; LI Yue; YANG Shu-sen; SHENG Li; YANG Ning; SHAN Hong-bo; XUE Hong-jie; LIU Wei; YANG Bao-feng; DONG De-li; LI Bao-xin

    2009-01-01

    Background We hypothesize that increased atrial oxidative stress and inflammation may play an important role in atrial nerve sprouting and heterogeneous sympathetic hyperinnervation during atrial fibrillation (AF). To test the hypothesis, we examined whether the antioxidant and anti-inflammatory treatment with probucol attenuates atrial autonomic remodeling in a canine model of AF produced by prolonged rapid right atrial pacing. Methods Twenty-one dogs were divided into a sham-operated group, a control group and a probucol group. Dogs in the control group and probucol group underwent right atrial pacing at 400 beats per minute for 6 weeks, and those in the probucol group received probucol 1 week before rapid atrial pacing until pacing stopped. After 6-week rapid atrial pacing, general properties including left atrial structure and function, atrial hemodynamics and the inducibility and duration of AF were measured in all the groups. Atrial oxidative stress markers and serum C-reactive protein (CRP) concentration were estimated. The degree of nerve sprouting and sympathetic innervation at the right atrial anterior wall (RAAW) and the left atrial anterior wall (LAAW) were quantified by immunohistochemistry, atdal norepinephrine contents were also detected. Atrial beta-nerve growth factor (beta-NGF) mRNA and protein expression at the RAAW and LAAW were assessed by real-time quantitative RT-PCR and Western blotting respectively. Results Atrial tachypacing induced significant nerve sprouting and heterogeneous sympathetic hyperinnervation, and the magnitude of nerve sprouting and hyperinnervation was higher in the RAAW than in the LAAW. Atrial beta-NGF mRNA and protein levels were significantly increased at the RAAW and LAAW, and the upregulation of beta-NGF expression was greater at the RAAW than at the LAAW in the control group. The beta-NGF protein level was positively correlated with the density of sympathetic nerves in all groups. Probucol decreased the increase of

  16. Improved poultry house

    Energy Technology Data Exchange (ETDEWEB)

    None

    1983-01-01

    The relationship of energy and poultry production was explored in three areas: methane production from litter, broiler house insulation, and broiler house HVAC systems. The findings show that while a methane plant would not be popular with individual American poultry producers; the pay back in fuel and fertilizer, if the plant was located in close proximinity to the processing plant, would be favorable. Broiler house insulation has been dramatically improved since the outset of this study. Presently, all new installations in the survey area are the Environmental houses which are fully insulated. HVAC systems have had to keep pace with the introduction of better insulation. The new Environmental houses HVAC systems are fully automated and operating on a positive atmosphere principal. Ammonia and other problems have been kept in check while reducing air changes per house from a high of 7 per hour to as little as 3 per hour.

  17. Effect of renal sympathetic denervation on atrial substrate remodeling in ambulatory canines with prolonged atrial pacing.

    Directory of Open Access Journals (Sweden)

    Xule Wang

    Full Text Available We have previously demonstrated that catheter-based renal sympathetic denervation (RSD could suppress atrial fibrillation (AF in canines with short-time rapid right atrial pacing (RAP. However, the role of renal denervation on atrial remodeling is unclear. The aim of the present study was to explore the long-term effect of RSD on the atrial remodeling during prolonged RAP. Twenty mongrel dogs were implanted with a high-frequency cardiac pacemaker with a transvenous lead inserted into the right atrial appendage. The dogs were divided into three groups: a sham-operated group (n = 6, the chronic RAP (CRAP group (n = 7, and the CRAP+RSD group (n = 7. In the CRAP+RSD group, a pacemaker was implanted 6 weeks after RSD was performed bilaterally for recovery. RAP was maintained for 5 weeks in CRAP group and CRAP+RSD group. The plasma levels of Angiotensin II and aldosterone were significantly increased in CRAP group compared with sham-operated group, but the increasing trend was inhibited in CRAP+RSD group compared with CRAP group (P<0.05. Similarly, RSD suppressed the increasing trend that prolonged RAP produced in the left atrial levels of ANP, TNF-α and IL-6. Compared with the sham-operated group, the CRAP group had significantly increased levels of caspase-3, bax and Cx40 whereas the level of Bcl-2 decreased (P<0.05. RSD markedly reduced the upregulation of caspase-3, bax and Cx40 and the downregulation of Bcl-2 expression compared with the CRAP group (P<0.05. Picric acid-sirius red staining study suggested that RSD could markedly alleviate the lesion degree of cardic fibrosis induced by CRAP (P<0.05. Immunohistochemistry results showed that the densities of TH- and GAP43- positive nerves were significantly elevated in the CRAP group compared with the sham-operated group, while RSD operation signicantly inhibited the these changes produced by CRAP. These findings suggest that renal denervation could suppress the atrial remodeling after

  18. Protein-pacing caloric-restriction enhances body composition similarly in obese men and women during weight loss and sustains efficacy during long-term weight maintenance

    DEFF Research Database (Denmark)

    Arciero, Paul J; Edmonds, Rohan; He, Feng;

    2016-01-01

    TBF, ABF, resting metabolic rate (RMR), and biomarkers between obese men and women during WL (weeks 0-12); and (2) mP-CR compared to a HH diet during WM (weeks 13-64). During WL, men (n = 21) and women (n = 19) were assessed for TBF, ABF, VAT, RMR, and biomarkers at weeks 0 (pre) and 12 (post). Men......Short-Term protein-pacing (P; ~6 meals/day, >30% protein/day) and caloric restriction (CR, ~25% energy deficit) improves total (TBF), abdominal (ABF) and visceral (VAT) fat loss, energy expenditure, and biomarkers compared to heart healthy (HH) recommendations (3 meals/day, 15% protein/day) in...... obese adults. Less is known whether obese men and women respond similarly to P-CR during weight loss (WL) and whether a modified P-CR (mP-CR) is more efficacious than a HH diet during long-term (52 week) weight maintenance (WM). The purposes of this study were to evaluate the efficacy of: (1) P-CR on...

  19. Comparative study of left ventricular function in patients with unstable angina, non-Q wave myocardial infarction and stable angina pectoris: assessment with atrial pacing and digital ventriculography.

    Science.gov (United States)

    Hussain, K M; Gould, L; Pomerantsev, E V; Angirekula, M; Bharathan, T

    1995-10-01

    To compare left ventricular global and segmental function at rest and during right atrial pacing in patients with unstable angina, non-Q wave myocardial infarction, and stable angina (class III angina), low-dose digital subtraction ventriculography was performed at rest and after abrupt cessation of pacing in 42 patients with unstable angina, 8 patients with non-Q wave myocardial infarction and 15 patients with stable angina during selective coronary arteriography. Left ventricular ejection fraction was significantly lower at rest in patients with unstable angina (P < 0.01) and non-Q wave myocardial infarction (P < 0.05) and during pacing (P < 0.01). These two groups of patients had significantly higher values of left ventricular end-diastolic and end-systolic volumes at rest and during pacing as compared with stable angina group. In comparing various clinical patterns of unstable angina, ejection fraction was significantly (P < 0.05) lower during pacing in patients with crescendo angina than in new-onset angina. However, ejection fraction was significantly (P < 0.01) lower in crescendo angina only at rest as compared with rest angina. The length of zone of severe hypokinesia was greater in unstable angina (P < 0.01) as well as in non-Q wave myocardial infarction (P < 0.05) both at rest and during pacing as compared with stable angina. Contractility of region of hypokinesia during pacing was higher (P < 0.01) in stable angina than in unstable angina and non-Q wave myocardial infarction. In analyzing segmental function in various subgroups of unstable angina, the authors found that the length of total hypokinesia was significantly higher (P < 0.05) during pacing in crescendo angina than in new-onset angina. Contractility of region of hypokinesia was lowest at rest and during pacing in patients with crescendo angina. This study demonstrates that patients with unstable angina as well as non-Q wave myocardial infarction were characterized by more pronounced global and

  20. Thermal and Cardiovascular Strain Mitigate the Potential Benefit of Carbohydrate Mouth Rinse During Self-Paced Exercise in the Heat

    OpenAIRE

    Cramer, Matthew N; Thompson, Martin W.; PÉRIARD, JULIEN D.

    2015-01-01

    Purpose: To determine whether a carbohydrate mouth rinse can alter self-paced exercise performance independently of a high degree of thermal and cardiovascular strain. Methods: Eight endurance-trained males performed two 40-km cycling time trials in 35°C, 60% RH while swilling a 20-ml bolus of 6.5% maltodextrin (CHO) or a color- and taste-matched placebo (PLA) every 5 km. Heart rate, power output, rectal temperature (Tre), and mean skin temperature (Tsk) were recorded continuously; cardiac...

  1. Thermal and cardiovascular strain mitigate the potential benefit of carbohydrate mouth rinse during self-paced exercise in the heat

    OpenAIRE

    Matthew eCramer; Martin eThompson; Julien ePériard

    2015-01-01

    Purpose: To determine whether a carbohydrate mouth rinse can alter self-paced exercise performance independently of a high degree of thermal and cardiovascular strain.Methods: Eight endurance-trained males performed two 40-km cycling time trials in 35°C, 60% RH while swilling a 20-ml bolus of 6.5% maltodextrin (CHO) or a colour- and taste-matched placebo (PLA) every 5 km. Heart rate, power output, rectal temperature (Tre), and mean skin temperature (Tsk) were recorded continuously; cardiac ou...

  2. Heat stress exacerbates the reduction in middle cerebral artery blood velocity during prolonged self-paced exercise.

    Science.gov (United States)

    Périard, J D; Racinais, S

    2015-06-01

    This study examined the influence of hyperthermia on middle cerebral artery mean blood velocity (MCA Vmean). Eleven cyclists undertook a 750 kJ self-paced time trial in HOT (35 °C) and COOL (20 °C) conditions. Exercise time was longer in HOT (56 min) compared with COOL (49 min; P partial pressure of CO2 (PETCO2 ; P pressure and oxygen uptake were lower from 50% of work completed onward in HOT compared with COOL (P pressure. PMID:25943664

  3. The influence of sex, age, and race experience on pacing profiles during the 90 km Vasaloppet ski race

    OpenAIRE

    Carlsson M; Assarsson H; Carlsson T

    2016-01-01

    Magnus Carlsson,1,2 Hannes Assarsson,1 Tomas Carlsson1,2 1School of Education, Health and Social Studies, Dalarna University, 2Dala Sports Academy, Falun, Sweden Abstract: The purpose of this study was to investigate pacing-profile differences during the 90 km Vasaloppet ski race related to the categories of sex, age, and race experience. Skiing times from eight sections (S1 to S8) were analyzed. For each of the three categories, 400 pairs of skiers were matched to have a finish time within ...

  4. Effect of atrial preference pacing on reducing long-term burden of atrial fibrillation:a clinical study

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical effect of atrial preference pacing (APP) on the prevention of paroxysmal atrial fibrillation. Methods: Based on the type of implanted pacemaker, 46 patients with sick sinus syndrome and paroxysmal atrial fibrillation were divided into two groups. Dual-chamber pacemaker equipped with APP function was implanted in patients of group APP (n=21), while conventional dual-chamber pacemaker was implanted in patients of control group (n=25). The patients were followed up for six months, the maximum P wave duration (Pmax), the P wave dispersion (Pd), the structure of heart chambers, the data of automatic mode switch (AMS) and the total burden of atrial fibrillation were estimated,and the results were statistically analyzed and compared between two groups. Results: The basic clinical characteristics of two groups were comparable. After six months pacing, the difference in Pmax between two groups was of no significance (115.0 ± 10.1 ms vs 122.0 ± 11.0 ms, P > 0.05), while the increase of Pd in control group was more obvious than that in group APP (32.7 ± 4.2 ms vs 20.1 ± 5.3 ms, P 0.05), and also no remarkable difference in the left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF) could be found (P > 0.05). Moreover, no significant difference existed between two groups (P > 0.05). After six months pacing,in group APP the frequencies of AMS decreased more sharply (145 ± 37 times vs 327 ± 13 times, P < 0.05), the duration of AMS shortened more apparently (73 ± 15 hours vs 139 ± 28 hours, P < 0.05) and the total burden of atrial fibrillation was alleviated more obviously (13 ± 5% vs 28 ± 6%, P < 0.05) when compared to those in control group. Conclusion: Atrial preference pacing can coordinate the anisotropy of double atrial depolarization, reduce the frequencies of long-term paroxysmal atrial fibrillation, shorten the duration of atrial fibrillation

  5. Uterine involution in colombian fine pace mares, measured by ultrasonography and endometrial cytology

    Directory of Open Access Journals (Sweden)

    Germán Ramírez

    2006-06-01

    Full Text Available Today, there still exists a controversial issue, as to the high incidence of early embryonic death in mares, mated on the first post partum oestrus. The purpose of this study was first, to determine the post partum period of uterine involution in fine pace Colombian mares using endometrial cytology and ultra sonograph. Secondly, to determine the relation between the neutrophil percentages found in cytology and the echogenicity of accumulated intrauterine fluid during the first 30 post partum days. Twenty (n=20 mares were examined beginning on the 6th post partum day and on alternate days, up to the 30th day. All subjects were grazing Kikuyo grass (Pennisetum clandestinum at la Sabana de Bogotá, 2.600 meters over sea level, 4 º north latitude and with an average temperature of 13 º C. From the 3rd postpartum day, all 20 mares were exposed to 2 healthy stallions, to establish their heat behaviour. Ten of them, following complete randomization, were inseminated on the first postpartum heat, while the others were inseminated on the second post partum heat. Genital examination was carried out by a technician, who did not know the reproductive history of any of the experimental mares. Examinations included rectal palpation, ultra sonograph (Pie Medical 480, linear array, 5 MHz, vaginal swabs and endometrial cytology. Uterine dimension was recorded by rectal palpation and ultra sonograph, it was included the uterine horn dimensions (tip, middle, and corporo-cornual junction of previously gravid and non gravid uterus. Intrauterine fluid detection was performed by the use of an echogenicity scale. Ovaric structures were recorded (preovulatory follicles and ovulation. Pregnancy diagnosis was performed on day 15 post ovulation and then confirmed on day 40. Endometrial cytology samples were taken from uterus after the perineal area was disinfected using non covered isopos with a Pollanski speculum. Smears specimens were fixed with metil alcohol for 15

  6. The effect of calcium antagonists on atrial natriuretic peptide (ANP) release from the rat heart during rapid cardiac pacing.

    Science.gov (United States)

    Doubell, A F

    1989-05-01

    The diuresis associated with rapid atrial rhythms is a well recognized clinical entity (Wood, 1963). Atrial natriuretic peptide (ANP) levels are elevated during rapid atrial rhythms (Hirata et al., 1987), including during rapid atrial pacing (Rankin et al., 1986; Schiebinger and Linden 1986; Walsh et al., 1987), and may contribute to the associated diuresis. Calcium channel antagonists are often used to treat atrial tachycardias but the effect this may have on ANP secretion and subsequent compensatory responses, such as a diuresis, is unknown. Reported here are experiments demonstrating that the increase in ANP secretion that accompanies rapid atrial pacing of the isolated perfused rat heart is abolished by calcium channel antagonists. This effect is not limited to a single class of calcium channel antagonists and could be demonstrated with Verapamil and Nifedipine. Although extrapolation to the in vivo situation should always be done with care, the results reported here contribute towards clarifying the effect of the calcium channel antagonists on the ANP response to rapid heart rates. PMID:2528639

  7. Chromosomal assignment of the genes for proprotein convertases PC4, PC5, and PACE 4 in mouse and human

    Energy Technology Data Exchange (ETDEWEB)

    Mbikay, M.; Seidah, N.G.; Chretien, M. [Univ. of Montreal, Quebec (Canada)] [and others

    1995-03-01

    The genes for three subtilisin/kexin-like proprotein convertases, PC4, PC5, and PACE4, were mapped in the mouse by RFLP analysis of a DNA panel from a (C57BL/6JEi x SPRET/Ei) F{sub 1} x SPRET/Ei backcross. The chromosomal locations of the human homologs were determined by Southern blot analysis of a DNA panel from human-rodent somatic cell hybrids, most of which contained a single human chromosome each. The gene for PC4 (Pcsk4 locus) mapped to mouse chromosome 10, close to the Adn (adipsin, a serine protease) locus and near the Amh (anti-Mullerian hormone) locus; in a human, the gene was localized to chromosome 19. The gene for PC5 (Pcsk5 locus) mapped to mouse chromosome 19 close to the Lpc1 (lipoacortin-1) locus and, in human, was localized to chromosome 9. The gene for PACE4 (Pcsk6 locus) mapped to mouse chromosome 7, at a distance of 13 cM from the Pcsk3 locus, which specifies furin, another member of this family of enzymes previoulsy mapped to this chromosome. This is in concordance with the known close proximity of these two loci in the homologous region on human chromosome 15q25-qter. Pcsk3 and Pcsk6 mapped to a region of mouse chromosome 7 that has been associated cytogenetically with postnatal lethality in maternal disomy, suggesting that these genes might be candidates for imprinting. 43 refs., 3 figs., 2 tabs.

  8. Freestyle race pacing strategies (400 m) of elite able-bodied swimmers and swimmers with disability at major international championships.

    Science.gov (United States)

    Taylor, Joseph B; Santi, Giampaolo; Mellalieu, Stephen D

    2016-10-01

    Freestyle race pacing strategies (400 m) were compared between elite able-bodied swimmers and those with minimal physical (International Paralympic Committee S10 classification) and visual disabilities (International Paralympic Committee S13 classification). Data comprised 50-m lap splits and overall race times from 1176 400-m freestyle swims from World Championships, European Championships and Olympic/Paralympic Games between 2006 and 2012. Five pacing strategies were identified across groups (even, fast start, negative, parabolic and parabolic fast start), with negative and even strategies the most commonly adopted. The negative pacing strategy produced the fastest race times for all groups except for female S13 swimmers where an even strategy was most effective. Able-bodied groups swam faster than their S10 and S13 counterparts, with no differences between S10 and S13 groups. The results suggest adoption of multiple pacing strategies across groups, and even where impairments are considered minimal they are still associated with performance detriments in comparison to their able-bodied counterparts. The findings have implications for the planning and implementation of training related to pacing strategies to ensure optimal swimmer preparation for competition. Analogous performance levels in S10 and S13 swimmers also suggest a case for integrated competition of these classifications in 400-m freestyle swimming. PMID:26854943

  9. Paced-mating increases the number of adult new born cells in the internal cellular (granular layer of the accessory olfactory bulb.

    Directory of Open Access Journals (Sweden)

    Rebeca Corona

    Full Text Available The continuous production and addition of new neurons during life in the olfactory bulb is well accepted and has been extensively studied in rodents. This process could allow the animals to adapt to a changing environment. Olfactory neurogenesis begins in the subventricular zone where stem cells proliferate and give rise to young undifferentiated neuroblasts that migrate along the rostral migratory stream to the olfactory bulb (OB. Olfaction is crucial for the expression of sexual behavior in rodents. In female rats, the ability to control the rate of sexual interactions (pacing has important physiological and behavioral consequences. In the present experiment we evaluated if pacing behavior modifies the rate of new cells that reach the main and accessory olfactory bulb. The BrdU marker was injected before and after different behavioral tests which included: females placed in a mating cage (control, females allowed to pace the sexual interaction, females that mated but were not able to control the rate of the sexual interaction and females exposed to a sexually active male. Subjects were sacrificed fifteen days after the behavioral test. We observed a significant increase in the density of BrdU positive cells in the internal cellular layer of the accessory olfactory bulb when females paced the sexual interaction in comparison to the other 3 groups. No differences in the cell density in the main olfactory bulb were found. These results suggest that pacing behavior promotes an increase in density of the new cells in the accessory olfactory bulb.

  10. 轻度心功能受损的高度房室传导阻滞患者采用中位间隔部起搏是否优于心尖部起搏?%Is right ventricular mid-septal pacing superior to apical pacing in patients with high degree atrio-ventricular block and moderately depressed left ventricular function?

    Institute of Scientific and Technical Information of China (English)

    Kang CHEN; Ying CHEN; Gang GU; Wei-feng SHEN; Li-qun WU; Ye MAO; Shao-hua LIU; Qiong WU; Qing-zhi LUO; Wen-qi PAN; Qi JIN; Ning ZHANG; Tian-you LING

    2014-01-01

    研究目的:对于轻度心功能受损的高度房室传导阻滞患者,明确右室起搏的最优化位置,同时明确哪一类患者能够从最优化的右心室起搏中获益。  创新要点:首次明确相比于右心室心尖部起搏,中位间隔部起搏明显改善轻度心功能受损,尤其是左室射血分数在35%~40%的高度房室传导阻滞患者的临床预后。  研究方法:随机分配进入中位间隔部起搏或心尖部起搏的患者,在基线状态下记录N-末端脑钠肽前体、六分钟步行试验以及心超结果;随访18个月后观察上述结果变化。同时,根据射血分数的不同进行亚组分析。  重要结论:相比于右心室心尖部起搏,中位间隔部起搏能够改善轻度心功能受损的高度房室传导阻滞患者的临床预后,尤其对于左室射血分数在35%~40%的患者。%Objective:We are aimed to investigate whether right ventricular mid-septal pacing (RVMSP) is superior to conventional right ventricular apical pacing (RVAP) in improving clinical functional capacity and left ventricular ejection fraction (LVEF) for patients with high-degree atrio-ventricular block and moderately depressed left ventricle (LV) function. Methods:Ninety-two patients with high-degree atrio-ventricular block and moderately reduced LVEF (ranging from 35%to 50%) were randomly allocated to RVMSP (n=45) and RVAP (n=47). New York Heart Association (NYHA) functional class, echocardiographic LVEF, and distance during a 6-min walk test (6MWT) were determined at 18 months after pacemaker implantation. Serum levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured using an enzyme-linked immunosorbent assay (ELISA) kit. Results:Compared with baseline, NYHA functional class remained unchanged at 18 months, distance during 6MWT (485 m vs. 517 m) and LVEF (36.7% vs. 41.8%) were increased, but BNP levels were reduced (2352 pg/ml vs. 710 pg/ml) in the RVMSP group

  11. Protein-Pacing Caloric-Restriction Enhances Body Composition Similarly in Obese Men and Women during Weight Loss and Sustains Efficacy during Long-Term Weight Maintenance.

    Science.gov (United States)

    Arciero, Paul J; Edmonds, Rohan; He, Feng; Ward, Emery; Gumpricht, Eric; Mohr, Alex; Ormsbee, Michael J; Astrup, Arne

    2016-01-01

    Short-Term protein-pacing (P; ~6 meals/day, >30% protein/day) and caloric restriction (CR, ~25% energy deficit) improves total (TBF), abdominal (ABF) and visceral (VAT) fat loss, energy expenditure, and biomarkers compared to heart healthy (HH) recommendations (3 meals/day, 15% protein/day) in obese adults. Less is known whether obese men and women respond similarly to P-CR during weight loss (WL) and whether a modified P-CR (mP-CR) is more efficacious than a HH diet during long-term (52 week) weight maintenance (WM). The purposes of this study were to evaluate the efficacy of: (1) P-CR on TBF, ABF, resting metabolic rate (RMR), and biomarkers between obese men and women during WL (weeks 0-12); and (2) mP-CR compared to a HH diet during WM (weeks 13-64). During WL, men (n = 21) and women (n = 19) were assessed for TBF, ABF, VAT, RMR, and biomarkers at weeks 0 (pre) and 12 (post). Men and women had similar reductions (p 50%) and increase in % lean body mass (9%). RMR (kcals/kg bodyweight) was unchanged and respiratory quotient decreased 9%. Twenty-four subjects (mP-CR, n = 10; HH, n = 14) completed WM. mP-CR regained significantly less body weight (6%), TBF (12%), and ABF (17%) compared to HH (p < 0.05). Our results demonstrate P-CR enhances weight loss, body composition and biomarkers, and maintains these changes for 52-weeks compared to a traditional HH diet. PMID:27483317

  12. 生物起搏在细胞移植中的作用%Effect of biological pacing on cell transplantation

    Institute of Scientific and Technical Information of China (English)

    罗时珂; 李萍

    2009-01-01

    近年来随着分子生物学、细胞移植及基因工程的快速发展,生物起搏成为治疗缓慢心律失常的新方向,生物起搏器的研究主要经历了3个阶段:①细胞治疗:将具有多向分化能力的胚胎干细胞或骨髓间充质干细胞植入心脏分化成起搏样细胞后发挥起搏功能.②基因转移:将窦房结细胞中的起搏基因通过载体转入心脏,使普通心肌细胞转化成自律细胞从而产生自主兴奋.③基因细胞治疗:将起搏基因转染干细胞后注入心脏,两者共同增强心肌生物起搏功能.尽管目前生物起搏器在大量动物实验中取得成功,但应用于临床仍面临许多问题,随着窦房结细胞起搏机制进一步阐明,心脏生物起搏器必将造福人类.%Recently years,with the rapid development of molecular biology,cell transplantation and genetic engineering,biological pacing has become the new direction of treatment for bradyarrhythmia.The researches on biological pacing mainly experience three stages:①Cell therapy:Embryonic stem cells or mesenchymal stem cells,who have the ability of multi-direction differentiation,can be differentiate into generate pacemaker cells to play pacing function after implanted into heart.②Gene transfer:The pacing genes in sinus node cells are delivered to heart by using of vectors,which make ordinary cardiomyocytes convert into automatic cells to generate spontaneous impulse.③Gene therapy:Stem cells are as platforms to carry pacemaker genes to heart and co-working to enhance myocardial pacing function.So far,biological pacing is successful in a lot of animal experiments,but it also face to many problems in clinical application.Along with further clarification on pacing mechanism of sinus code cells,biological pacing will benefit mankind.

  13. Patient Activation through Counseling and Exercise – Acute Leukemia (PACE-AL) – a randomized controlled trial

    DEFF Research Database (Denmark)

    Jarden, Mary; Møller, Tom; Kjeldsen, Lars;

    2013-01-01

    treatment related symptoms and side effects. To date, there are no clinical practice exercise guidelines for patients with acute leukemia undergoing induction and consolidation chemotherapy. A randomized controlled trial is needed to determine if patients with acute leukemia can benefit by a structured and...... supervised counseling and exercise program.Methods/design: This paper presents the study protocol: Patient Activation through Counseling and Exercise -- Acute Leukemia (PACE-AL) trial, a two center, randomized controlled trial of 70 patients with acute leukemia (35 patients/study arm) following induction...... chemotherapy in the outpatient setting. Eligible patients will be randomized to usual care or to the 12 week exercise and counseling program. The intervention includes 3 hours + 30 minutes per week of supervised and structured aerobic training (moderate to high intensity 70 - 80%) on an ergometer cycle...

  14. Pace:pienen jalanjäljen koti spontaanin kaupunkikehittämisen välineenä

    OpenAIRE

    Säilynoja, A. (Anu)

    2016-01-01

    Anu Säilynojan diplomityön, Pace -pienen jalanjäljen koti spontaanin kaupunkikehittämisen välineenä, tarkoitus on etsiä globaalien ympäristö-, ja sosiaalisten ongelmien aiheuttamaan tilanteeseen sopeutuvaa ja monistettavaa asumisen tapaa, konseptia, joka mahdollistaisi ihmisarvoisen elämän ja kodin useammalle; sallisi kaupunkien väestönkasvun kestävällä tavalla samalla pienentäen asukkaidensa ekologista jalanjälkeä. Diplomityössä selvitetään kestämättömään tilanteeseen johtaneita syitä ja spo...

  15. Human activities and climate variability drive fast-paced change across the world's estuarine-coastal ecosystems

    Science.gov (United States)

    Cloern, James E.; Abreu, Paulo C.; Carstensen, Jacob; Chauvaud, Laurent; Elmgren, Ragnar; Grall, Jacques; Greening, Holly; Johansson, John O.R.; Kahru, Mati; Sherwood, Edward T.; Xu, Jie; Yin, Kedong

    2016-01-01

    Time series of environmental measurements are essential for detecting, measuring and understanding changes in the Earth system and its biological communities. Observational series have accumulated over the past 2–5 decades from measurements across the world's estuaries, bays, lagoons, inland seas and shelf waters influenced by runoff. We synthesize information contained in these time series to develop a global view of changes occurring in marine systems influenced by connectivity to land. Our review is organized around four themes: (i) human activities as drivers of change; (ii) variability of the climate system as a driver of change; (iii) successes, disappointments and challenges of managing change at the sea-land interface; and (iv) discoveries made from observations over time. Multidecadal time series reveal that many of the world's estuarine–coastal ecosystems are in a continuing state of change, and the pace of change is faster than we could have imagined a decade ago. Some have been transformed into novel ecosystems with habitats, biogeochemistry and biological communities outside the natural range of variability. Change takes many forms including linear and nonlinear trends, abrupt state changes and oscillations. The challenge of managing change is daunting in the coastal zone where diverse human pressures are concentrated and intersect with different responses to climate variability over land and over ocean basins. The pace of change in estuarine–coastal ecosystems will likely accelerate as the human population and economies continue to grow and as global climate change accelerates. Wise stewardship of the resources upon which we depend is critically dependent upon a continuing flow of information from observations to measure, understand and anticipate future changes along the world's coastlines.

  16. The effect of age and microstructural white matter integrity on lap time variation and fast-paced walking speed.

    Science.gov (United States)

    Tian, Qu; Ferrucci, Luigi; Resnick, Susan M; Simonsick, Eleanor M; Shardell, Michelle D; Landman, Bennett A; Venkatraman, Vijay K; Gonzalez, Christopher E; Studenski, Stephanie A

    2016-09-01

    Macrostructural white matter damage (WMD) is associated with less uniform and slower walking in older adults. The effect of age and subclinical microstructural WM degeneration (a potentially earlier phase of WM ischemic damage) on walking patterns and speed is less clear. This study examines the effect of age on the associations of regional microstructural WM integrity with walking variability and speed, independent of macrostructural WMD. This study involved 493 participants (n = 51 young; n = 209 young-old; n = 233 old-old) from the Baltimore Longitudinal Study of Aging. All completed a 400-meter walk test and underwent a concurrent brain MRI with diffusion tensor imaging. Microstructural WM integrity was measured as fractional anisotropy (FA). Walking variability was measured as trend-adjusted variation in time over ten 40-meter laps (lap time variation, LTV). Fast-paced walking speed was assessed as mean lap time (MLT). Multiple linear regression models of FA predicting LTV and MLT were adjusted for age, sex, height, weight, and WM hyperintensities. Independent of WM hyperintensities, lower FA in the body of the corpus callosum was associated with higher LTV and longer MLT only in the young-old. Lower FA in superior longitudinal, inferior fronto-occipital, and uncinate fasciculi, the anterior limb of the internal capsule, and the anterior corona radiate was associated with longer MLT only in the young-old. While macrostructural WMD is known to predict more variable and slower walking in older adults, microstructural WM disruption is independently associated with more variable and slower fast-paced walking only in the young-old. Disrupted regional WM integrity may be a subclinical contributor to abnormal walking at an earlier phase of aging. PMID:26399234

  17. Brisk heart rate and EEG changes during execution and withholding of cue-paced foot motor imagery

    Directory of Open Access Journals (Sweden)

    Robert J Barry

    2013-07-01

    Full Text Available Cue-paced motor imagery is a frequently used mental strategy to realize a Brain-Computer Interace (BCI. Recently it has been reported that 2 motor imagery tasks can be separated with a high accuracy within the first second after cue presentation onset. To investigate this phenomenon in detail we studied the dynamics of motor cortex beta oscillations in EEG and the changes in heart rate (HR during visual cue-paced foot imagery using a go (execution of imagery versus nogo (withholding of imagery paradigm in 16 healthy subjects. Both execution and withholding of motor imagery resulted in a brisk centrally localized beta ERD with a maximum at ~ 400 ms and a concomitant HR deceleration. We found that response patterns within the first second after stimulation differed between conditions. The ERD was significantly larger in go as compared to nogo. In contrast the HR deceleration was somewhat smaller and followed by an acceleration in go as compared to nogo. These findings suggest that the early beta ERD reflects visually induced preparatory activity in motor cortex networks. Both the early beta ERD and HR deceleration are the result of automatic operating processes that are likely part of the orienting reflex. Of interest, however, is that the preparatory cortical activity is strengthened and the HR modulated already within the first second after stimulation during the execution of motor imagery. The subtraction of the HR time course of the nogo from the go condition revealed a slight HR acceleration in the first seconds most likely due to the increased mental effort associated with the imagery process.

  18. The Organizational Fitness Navigator: Creating and Measuring Organizational Fitness for Fast-Paced Transformation

    OpenAIRE

    Voelpel, Sven C.; Leibold, Marius; Mahmoud, Khalid M.

    2003-01-01

    In the fast-changing environment of today dynamic capabilities to manage organizational transformation are regarded as crucial for business survival and improved performance. Although dynamic organizational capabilities have been receiving intense scrutiny by researchers and practitioners in the past few years, relatively little attention has been directed towards creating a systemic model of dynamic capabilities, and how to effectively measure what the authors call organizational fitness cap...

  19. Comparing the Effectiveness of Self-Paced and Collaborative Frame-of-Reference Training on Rater Accuracy in a Large-Scale Writing Assessment

    Science.gov (United States)

    Raczynski, Kevin R.; Cohen, Allan S.; Engelhard, George, Jr.; Lu, Zhenqiu

    2015-01-01

    There is a large body of research on the effectiveness of rater training methods in the industrial and organizational psychology literature. Less has been reported in the measurement literature on large-scale writing assessments. This study compared the effectiveness of two widely used rater training methods--self-paced and collaborative…

  20. CHADS2 and CHA2DS2-VASc score to assess risk of stroke and death in patients paced for sick sinus syndrome

    DEFF Research Database (Denmark)

    Svendsen, Jesper Hastrup; Nielsen, Jens Cosedis; Darkner, Stine;

    2013-01-01

    The risk of stroke in patients with atrial fibrillation (AF) can be assessed by use of the CHADS2 and the CHA2DS2-VASc score system. We hypothesised that these risk scores and their individual components could also be applied to patients paced for sick sinus syndrome (SSS) to evaluate risk of...

  1. Financial Analysis. Unit 18. Level 1. Instructor Guide. PACE: Program for Acquiring Competence in Entrepreneurship. Third Edition. Research & Development Series No. 301-18.

    Science.gov (United States)

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This instructor guide for a unit on financial analysis in the PACE (Program for Acquiring Competence in Entrepreneurship) curriculum includes the full text of the student module and lesson plans, instructional suggestions, and other teacher resources. The competencies that are incorporated into this module are at Level 1 of learning--understanding…

  2. Financial Analysis. Unit 18. Level 2. Instructor Guide. PACE: Program for Acquiring Competence in Entrepreneurship. Third Edition. Research & Development Series No. 302-18.

    Science.gov (United States)

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This instructor guide for a unit on financial analysis in the PACE (Program for Acquiring Competence in Entrepreneurship) curriculum includes the full text of the student module and lesson plans, instructional suggestions, and other teacher resources. The competencies that are incorporated into this module are at Level 2 of learning--planning for…

  3. Can SPOC (Self-Paced Online Course) Live Long and Prosper? A Comparison Study of a New Species of Online Course Delivery

    Science.gov (United States)

    Southard, Sheryne; Meddaugh, Joshua; France-Harris, Antoinette

    2015-01-01

    Numerous formats exist for online course delivery: pure online, blended or hybrid, flipped and web-enhanced. The literature is replete with comparison studies on the efficacy of online, hybrid and traditional format courses. However, the self-paced online course, a relatively new and rare variation, has received very little coverage in the body of…

  4. Pricing Strategy. Unit 10. Level 2. Instructor Guide. PACE: Program for Acquiring Competence in Entrepreneurship. Third Edition. Research & Development Series No. 302-10.

    Science.gov (United States)

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This instructor guide for a unit on pricing strategy in the PACE (Program for Acquiring Competence in Entrepreneurship) curriculum includes the full text of the student module and lesson plans, instructional suggestions, and other teacher resources. The competencies that are incorporated into this module are at Level 2 of learning--planning for a…

  5. Pricing Strategy. Unit 10. Level 1. Instructor Guide. PACE: Program for Acquiring Competence in Entrepreneurship. Third Edition. Research & Development Series No. 301-10.

    Science.gov (United States)

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This instructor guide for a unit on pricing strategy in the PACE (Program for Acquiring Competence in Entrepreneurship) curriculum includes the full text of the student module and lesson plans, instructional suggestions, and other teacher resources. The competencies that are incorporated into this module are at Level 1 of learning--understanding…

  6. Pricing Strategy. Unit 10. Level 3. Instructor Guide. PACE: Program for Acquiring Competence in Entrepreneurship. Third Edition. Research & Development Series No. 303-10.

    Science.gov (United States)

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This instructor guide for a unit on pricing strategy in the PACE (Program for Acquiring Competence in Entrepreneurship) curriculum includes the full text of the student module and lesson plans, instructional suggestions, and other teacher resources. The competencies that are incorporated into this module are at Level 3 of learning--starting and…

  7. Animacy Affects the Processing of Subject-Object Ambiguities in the Second Language: Evidence from Self-Paced Reading with German Second Language Learners of Dutch

    Science.gov (United States)

    Jackson, Carrie N.; Roberts, Leah

    2010-01-01

    The results of a self-paced reading study with German second language (L2) learners of Dutch showed that noun animacy affected the learners' on-line commitments when comprehending relative clauses in their L2. Earlier research has found that German L2 learners of Dutch do not show an on-line preference for subject-object word order in temporarily…

  8. Relationship between seasonal weather changes, risk of dehydration, and incidence of severe bradyarrhythmias requiring urgent temporary transvenous cardiac pacing in an elderly population

    Science.gov (United States)

    Palmisano, Pietro; Accogli, Michele; Zaccaria, Maria; Vergari, Alessandra; De Luca De Masi, Gabriele; Negro, Luca; De Blasi, Sergio

    2014-09-01

    There is little information on any seasonal variations or meteorological factors associated with symptomatic bradyarrhythmias requiring cardiac pacing. The aim of this single-center study was to investigate the seasonal distribution of the incidence of severe, life-threatening bradyarrhythmias requiring urgent temporary transvenous cardiac pacing in an elderly population. Consecutive patients who underwent urgent temporary transvenous cardiac pacing between 2007 and 2012 were enrolled. The baseline characteristics of the patients and some meteorological parameters, including the calculation the daily heat index (HI), were recorded. During the study period, 79 consecutive patients (mean age 82 ± 8 years, 41 % male) underwent urgent temporary transvenous cardiac pacing, mainly for third-degree atrioventricular block (79 %). The incidence of bradyarrhythmias was significantly higher in summer than in the other seasons ( P 90 °F for >3 h per day for at least 10 days ( P renal function impairment and hyperkalemia (all P < 0.05). This study showed an increased incidence of severe bradyarrhythmias in an elderly population during the hottest months of the year. In these months, in subjects characterized by increased susceptibility to dehydration, the risk of developing bradyarrhythmias was increased significantly.

  9. Improving human performance: Industry factors influencing the ability to perform

    OpenAIRE

    Güera Massyn Romo

    2013-01-01

    Learning interventions and new technologies that aim to improve human performance must take cognisance of industry factors inhibiting human performance. The dynamic and fast pace nature of the Information and Communication Technologies (ICT) and the engineering industries do not lend themselves to proper skills planning and management. These industries experience real skills gaps, to some of which they contribute by themselves. This study reports on these performance-inhibiting factors such a...

  10. Levodopa reinstates connectivity from prefrontal to premotor cortex during externally paced movement in Parkinson's disease

    DEFF Research Database (Denmark)

    Herz, Damian M; Siebner, Hartwig R; Hulme, Oliver J;

    2014-01-01

    Dopamine deficiency affects functional integration of activity in distributed neural regions. It has been suggested that lack of dopamine induces disruption of neural interactions between prefrontal and premotor areas, which might underlie impairment of motor control observed in patients with Par......Dopamine deficiency affects functional integration of activity in distributed neural regions. It has been suggested that lack of dopamine induces disruption of neural interactions between prefrontal and premotor areas, which might underlie impairment of motor control observed in patients......-coupling as well as cross-frequency θ-γ coupling was observed from PFC to lPM. Enhancement of this cross-frequency θ-γ coupling after application of levodopa was positively correlated with individual improvement in motor function. The results demonstrate that dopamine deficiency impairs the ability to establish...

  11. Cognitive activity for the treatment of older adults with mild Alzheimer's Disease (AD - PACE AD: study protocol for a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Almeida Osvaldo P

    2011-02-01

    Full Text Available Abstract Background Participation in cognitive stimulation therapy (CST may reduce the rate of cognitive decline in people with Alzheimer's disease (AD, however it is unclear if the training of carers to deliver activities is sufficient to improve the clinical outcome of patients. The Promoting Healthy Ageing with Cognitive Exercise for Alzheimer's Disease (PACE-AD study has been designed to determine if change in cognitive function over a six month period can be achieved with participation in cognitive stimulating activities when the intervention is delivered to carers only as opposed to carers and patients. Methods/Design The study will aim to recruit 128 community-dwelling men and women with probable AD according to NINCDS-ADRDS criteria. Participants will be randomly allocated to one of two cognitive activity treatment groups: (1 Participants with mild AD and their companions together (2 Companions of participants with mild AD alone. The intervention will consist of a twelve-week program of cognitive stimulation. Seven weeks of the program will involve 90-minute group sessions delivered once per week while the remaining weeks of the program will involve structured home based activities with telephone support. The primary outcome measure of the study is the change from baseline in the total score on the Alzheimer Disease Assessment Scale-Cognitive (ADAS-COG. Secondary outcomes of interest include changes in health related quality of life, mood, memory, language, executive functions, independent living abilities and psychiatric symptoms for participants with mild AD. Changes in companion quality of life, mood, and general health will also be monitored. Primary endpoints will be collected 13 and 26 weeks after the baseline assessment. Discussion The proposed project will provide evidence as to whether CST for people with AD and their companions is more beneficial than when used for companions alone. Outcomes sought include a reduction of

  12. Impacto da troponina I cardíaca sérica na evolução tardia de pacientes submetidos a ressincronização com estimulação biventricular: seguimento de até 59 meses Impact of serum troponin I in the long-term evolution of patients submitted to resynchronization with biventricular stimulation: follow-up of up to 59 months

    Directory of Open Access Journals (Sweden)

    João Carlos F. Leal

    2005-09-01

    , no deaths occurred and of the 8 patients with high levels, six died (p-value = 0.0003. The actuarial survival curve showed a survival rate of 47.1 ± 13.3% at the end of 59 months. CONCLUSION: VR in patients with CHF improves the QV and echocardiographic parameters (ejection fraction and LVDD. It is a good alternative for functional class III and IV patients. The serum levels of cardiac troponin I are predictors of risk to life.

  13. Centennial-scale climate change from decadally-paced explosive volcanism: a coupled sea ice-ocean mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Y. [University of Colorado, INSTAAR, Boulder, CO (United States); Miller, G.H. [University of Colorado, INSTAAR, Boulder, CO (United States); University of Colorado, Department of Geological Sciences, Boulder, CO (United States); Otto-Bliesner, B.L.; Holland, M.M.; Bailey, D.A. [NCAR, Boulder, CO (United States); Schneider, D.P. [NCAR, Boulder, CO (United States); University of Colorado, CIRES, Boulder, CO (United States); Geirsdottir, A. [University of Iceland, Department of Earth Sciences and Institute of Earth Sciences, Reykjavik (Iceland)

    2011-12-15

    Northern Hemisphere summer cooling through the Holocene is largely driven by the steady decrease in summer insolation tied to the precession of the equinoxes. However, centennial-scale climate departures, such as the Little Ice Age, must be caused by other forcings, most likely explosive volcanism and changes in solar irradiance. Stratospheric volcanic aerosols have the stronger forcing, but their short residence time likely precludes a lasting climate impact from a single eruption. Decadally paced explosive volcanism may produce a greater climate impact because the long response time of ocean surface waters allows for a cumulative decrease in sea-surface temperatures that exceeds that of any single eruption. Here we use a global climate model to evaluate the potential long-term climate impacts from four decadally paced large tropical eruptions. Direct forcing results in a rapid expansion of Arctic Ocean sea ice that persists throughout the eruption period. The expanded sea ice increases the flux of sea ice exported to the northern North Atlantic long enough that it reduces the convective warming of surface waters in the subpolar North Atlantic. In two of our four simulations the cooler surface waters being advected into the Arctic Ocean reduced the rate of basal sea-ice melt in the Atlantic sector of the Arctic Ocean, allowing sea ice to remain in an expanded state for > 100 model years after volcanic aerosols were removed from the stratosphere. In these simulations the coupled sea ice-ocean mechanism maintains the strong positive feedbacks of an expanded Arctic Ocean sea ice cover, allowing the initial cooling related to the direct effect of volcanic aerosols to be perpetuated, potentially resulting in a centennial-scale or longer change of state in Arctic climate. The fact that the sea ice-ocean mechanism was not established in two of our four simulations suggests that a long-term sea ice response to volcanic forcing is sensitive to the stability of the seawater

  14. Understanding the physics of ELM pacing via vertical kicks in JET in view of ITER

    Science.gov (United States)

    de la Luna, E.; Chapman, I. T.; Rimini, F.; Lomas, P. J.; Saibene, G.; Koechl, F.; Sartori, R.; Saarelma, S.; Albanese, R.; Flanagan, J.; Maviglia, F.; Parail, V.; Sips, A. C. C.; Solano, E. R.; contributors, JET

    2016-02-01

    Experiments on JET, with both the previous carbon wall (JET-C) and the new Be/W wall (JET-ILW), have demonstrated the efficacy of using a fast vertical plasma motion (known as vertical kicks in JET) for active ELM control. In this paper we report on a series of experiments that have been recently conducted in JET-ILW with the goal of further improving the physics understanding of the processes governing the triggering of ELMs via vertical kicks. This is a necessary step to confidently extrapolate this ELM control method to ITER. Experiments have shown that ELMs can be reliably triggered provided a minimum vertical plasma displacement and velocity is imposed. The magnitude of the minimum displacement depends on the plasma parameters, being smaller for higher pedestal temperatures and lower collisionalities, which is encouraging in view of ITER. Modelling and stability analysis suggest that a localized current density induced by the vertical plasma movement close to the separatrix plays a major role in the ELM triggering mechanism, which is consistent with the experimental observations. The implications of these results for the extrapolation of this ELM control scheme to ITER are discussed.

  15. FDG PET as a predictor of response to resynchronisation therapy in patients with ischaemic cardiomyopathy

    International Nuclear Information System (INIS)

    Although resynchronisation therapy (CRT) is a promising addition to heart failure therapy, a substantial number of patients do not respond to CRT. As FDG PET has routinely been used for prediction of improvement after revascularisation in ischaemic cardiomyopathy, it was hypothesised that there is also a relationship between the extent of viable tissue and improvement as a result of CRT. Thirty-nine patients with ischaemic cardiomyopathy (ejection fraction 27 ± 9%) and a wide QRS complex underwent temporary pacing to determine the optimal pacing combination, i.e. that with the highest increase in cardiac index (CI) compared with baseline (measured by Doppler echocardiography). All patients also underwent FDG PET imaging. In 19 patients, CI measurements were repeated 10-12 weeks after permanent biventricular pacemaker implantation. Echocardiography (13-segment model) showed a mean of 9.8 ± 1.6 dyssynergic segments, with preserved FDG uptake in 4.1 ± 2.4 segments. CI improvement at the optimal pacing site was 20 ± 9%. There was a linear relationship between the extent of viable tissue and CI improvement during pacing (p 15%). The relation between CI improvement and viable tissue was similar at follow-up. A correlation was found between the extent of viable tissue and the haemodynamic response to CRT in patients with ischaemic cardiomyopathy, suggesting that FDG PET imaging may be useful to discriminate between responders and non-responders to CRT. (orig.)

  16. Combining data in non-destructive testing; Fusion de donnees en CND pour le projet pace

    Energy Technology Data Exchange (ETDEWEB)

    Lavayssiere, B.

    1994-03-01

    Non-destructive testing of some components requires quite often the use of several methods such as X-ray, ultrasonics, Eddy Currents. But the efficiency of a NDT method is highly dependent on the fact that the detectability of flaws in a specimen relies on the choice of the best method. Moreover a lot of inspection issues could benefit from the use of more than one test method, as each NDT method has its own physical properties and technological limits. Some questions still remain: how to combine data, at what level and for what functionality. Simple monomethod processes are well-known now. They include techniques like reconstruction which belongs to the so-called ill-posed problems in the field of mathematics. For NDT data processing, it has the ability to estimate real data from distorted ones coming from a probe. But, up to now there has been very few approaches for computer aided combination of results from different advanced techniques. This report presents the various mathematical fields involved towards that goal (statistical decision theory which allows the use of multiple hypothesis, non-linear decision theory for its capability to classify and to discriminate, graph theory to find the optimal path in an hypothesis graph and also fuzzy logic, multiple resolution analysis, artificial intelligence,...) and which combinations of methods are useful. Some images will illustrate this topic in which EDF is involved, and will explain what are the major goals of this work. Combining is not only an improvement of 3D visualisation which would allow to display simultaneously CAD or NDT data for example, but it consists in exploiting multisensor data collected via a variety of sophisticated techniques and presenting this information to the operator without overloading the operator/system capacities in order to reduce the uncertainty and to resolve the ambiguity inherent to mono method inspection. (author). 7 figs., 35 refs.

  17. Biventricular Takotsubo vs Myocarditis – a diagnostic challenge

    OpenAIRE

    de Abreu, G.; Azevedo, P.; Vieira, C; Arantes, C; MARTINS, J.; Galvão-Braga, C; Rodrigues, C; Salomé, N; J. MARQUES

    2015-01-01

    Background: Takotsubo cardiomyopathy (TCM) is an important differential diagnosis of acute coronary syndrome and myocarditis. It is characterized by normal or near-normal coronary arteries and regional wall motion abnormalities that extend beyond a single coronary vascular bed. Variants of the classical left ventricular (LV) apical ballooning are increasing in recognition as cardiac magnetic resonance (CMR) is more extensively used. Case report: We present a case of 69-year-old woman with ...

  18. Keeping Pace with Criminals: An Extended Study of Designing Patrol Allocation against Adaptive Opportunistic Criminals

    Directory of Open Access Journals (Sweden)

    Chao Zhang

    2016-06-01

    demonstrate the efficiency of our learning algorithms by applying them to a real dataset of criminal activity obtained from the police department of the University of Southern California (USC situated in Los Angeles, CA, USA. We project a significant reduction in crime rate using our planning strategy as compared to the actual strategy deployed by the police department. We also demonstrate the improvement in crime prevention in simulation when we use our iterative planning and learning mechanism when compared to just learning once and planning. Finally, we introduce a web-based software for recommending patrol strategies, which is currently deployed at USC. In the near future, our learning and planning algorithm is planned to be integrated with this software. This work was done in collaboration with the police department of USC.

  19. Prevalence of tension-type headache in adult general population: the PACE study and review of the literature.

    Science.gov (United States)

    Ferrante, T; Manzoni, G C; Russo, M; Camarda, C; Taga, A; Veronesi, L; Pasquarella, C; Sansebastiano, G; Torelli, P

    2013-05-01

    The mean global prevalence of tension-type headache (TTH) in adult is 42 %. To date, there have been no Italian studies on TTH prevalence in the adult general population. Therefore, we conducted a cross-sectional study, called PACE (PArma CEfalea, or "Headache in Parma"), aimed at detecting the prevalence and clinical features of primary headaches in the city of Parma's adult general population. Crude past-year prevalence for definite TTH was 19.4 % (95 % CI 16.8-21.9), namely 9.0 % (95 % CI 7.1-10.8) for infrequent TTH, 9.8 % (95 % CI 7.9-11.8) for frequent TTH, and 0.6 % (95 % CI 0.1-1) for chronic TTH. Crude prevalence for probable TTH was 2.3 % (95 % CI 1.3-3.3). Our study results indicate a TTH prevalence rate (19.4 %) at the lower limit of data ranges currently available for Western countries, and prevalence rates for infrequent forms (9 %) do not appear much different from those of frequent forms (9.8 %). PMID:23695063

  20. Energy system contribution in a maximal incremental test: correlations with pacing and overall performance in a 10-km running trial

    Directory of Open Access Journals (Sweden)

    M.V. Damasceno

    2015-11-01

    Full Text Available This study aimed to verify the association between the contribution of energy systems during an incremental exercise test (IET, pacing, and performance during a 10-km running time trial. Thirteen male recreational runners completed an incremental exercise test on a treadmill to determine the respiratory compensation point (RCP, maximal oxygen uptake (V˙O2max, peak treadmill speed (PTS, and energy systems contribution; and a 10-km running time trial (T10-km to determine endurance performance. The fractions of the aerobic (WAER and glycolytic (WGLYCOL contributions were calculated for each stage based on the oxygen uptake and the oxygen energy equivalents derived by blood lactate accumulation, respectively. Total metabolic demand (WTOTAL was the sum of these two energy systems. Endurance performance during the T10-km was moderately correlated with RCP, V˙O2maxand PTS (P<@0.05, and moderate-to-highly correlated with WAER, WGLYCOL, and WTOTAL (P<0.05. In addition, WAER, WGLYCOL, and WTOTAL were also significantly correlated with running speed in the middle (P<0.01 and final (P<0.01 sections of the T10-km. These findings suggest that the assessment of energy contribution during IET is potentially useful as an alternative variable in the evaluation of endurance runners, especially because of its relationship with specific parts of a long-distance race.

  1. The assessment of human health impact caused by industrial and civil activities in the Pace Valley of Messina.

    Science.gov (United States)

    Morra, P; Lisi, R; Spadoni, G; Maschio, G

    2009-06-01

    The impact of industrial and civil activities on an agricultural and residential area is presented in a detailed and global analysis. The examined area is the Pace river valley situated in the northern zone of Messina (Italy). The sources of pollution present in the area are: a Municipal Solid Waste Incinerator operating since 1979, a disused urban solid waste landfill which was used for 30 years, an urban solid waste treatment facility with heavy vehicles traffic, and two open pits for the production of bitumen. Large quantities of toxic, carcinogenic substances and criteria pollutants are released into the environment and represent potential hazards to human health. The analysis is performed using the EHHRA-GIS tool which employs an integrated, multimedia, multi-exposure pathways and multi-receptor risk assessment model that is able to manage all the steps which constitute the human health risk analysis in a georeferenced structure. The transport of pollutants in different environmental media is assessed applying models (AERMOD, GMS, CALINE) that take into account the particular three-dimensional morphology of the terrain. The results obtained, combined with a probabilistic risk assessment and a sensitivity analysis of calculation parameters, are a comprehensive assessment of the total human health risk in the area. Finally human health risks caused by toxic and carcinogenic substances are compared with acceptable legal limits in order to support environmental managers' decisions. PMID:19344932

  2. Photoperiod length paces the temporal orchestration of cell cycle and carbon-nitrogen metabolism in Crocosphaera watsonii.

    Science.gov (United States)

    Dron, Anthony; Rabouille, Sophie; Claquin, Pascal; Talec, Amélie; Raimbault, Virginie; Sciandra, Antoine

    2013-12-01

    We analysed the effect of photoperiod length (PPL) (16:8 and 8:16 h of light-dark regime, named long and short PPL, respectively) on the temporal orchestration of the two antagonistic, carbon and nitrogen acquisitions in the unicellular, diazotrophic cyanobacterium Crocosphaera watsonii strain WH8501 growing diazotrophically. Carbon and nitrogen metabolism were monitored at high frequency, and their patterns were compared with the cell cycle progression. The oxygen-sensitive N2 fixation process occurred mainly during the dark period, where photosynthesis cannot take place, inducing a light-dark cycle of cellular C : N ratio. Examination of circadian patterns in the cell cycle revealed that cell division occurred during the midlight period, (8 h and 4 h into the light in the long and short PPL conditions, respectively), thus timely separated from the energy-intensive diazotrophic process. Results consistently show a nearly 5 h time lag between the end of cell division and the onset of N2 fixation. Shorter PPLs affected DNA compaction of C. watsonii cells and also led to a decrease in the cell division rate. Therefore, PPL paces the growth of C. watsonii: a long PPL enhances cell division while a short PPL favours somatic growth (biomass production) with higher carbon and nitrogen cell contents. PMID:23841885

  3. Early to middle Miocene vegetation history of Antarctica supports eccentricity-paced warming intervals during the Antarctic icehouse phase

    Science.gov (United States)

    Griener, Kathryn W.; Warny, Sophie; Askin, Rosemary; Acton, Gary

    2015-04-01

    Recent palynological evidence from the upper section (warm period during the Mid Miocene Climatic Optimum (MMCO), during Antarctica's icehouse phase. The nature of other Miocene climate fluctuations in Antarctica remains poorly resolved. Here, we present new palynological data from the lower section of the AND-2A core (> 664 mbsf) that reveal additional intervals of increased palynomorph abundance and diversity during the Antarctic early to middle Miocene. This evidence is consistent with a relatively dynamic early Miocene Antarctic icehouse climate with intervals of increased temperature and moisture, prior to the MMCO. Comparison with previous AND-2A studies indicates that periods of increased palynomorph abundance in the lower stratigraphic section largely coincide with ice sheet minima, distal ice conditions, and the presence of freshwater (i.e. increased precipitation, meltwater run-off, and freshwater ponds). Decreases in plant productivity mostly coincide with increased glaciation, decreased freshwater, and ice-proximal conditions during the Antarctic Miocene. Comparing the palynological data with other AND-2A data and global climate proxies (e.g., pCO2, δ18O, relative sea level, Milankovitch cycles) helps to resolve questions regarding the driving forces behind climate and vegetation change. We found that palynomorph assemblages reflecting generally warmer conditions are largely associated with 400-kyr eccentricity maxima, while assemblages indicative of colder conditions coincide with 400-kyr eccentricity minima. These data are consistent with other findings that indicate the early to middle Miocene climate was eccentricity-paced.

  4. Application of a hybrid wavelet feature selection method in the design of a self-paced brain interface system

    Directory of Open Access Journals (Sweden)

    Birch Gary E

    2007-04-01

    Full Text Available Abstract Background Recently, successful applications of the discrete wavelet transform have been reported in brain interface (BI systems with one or two EEG channels. For a multi-channel BI system, however, the high dimensionality of the generated wavelet features space poses a challenging problem. Methods In this paper, a feature selection method that effectively reduces the dimensionality of the feature space of a multi-channel, self-paced BI system is proposed. The proposed method uses a two-stage feature selection scheme to select the most suitable movement-related potential features from the feature space. The first stage employs mutual information to filter out the least discriminant features, resulting in a reduced feature space. Then a genetic algorithm is applied to the reduced feature space to further reduce its dimensionality and select the best set of features. Results An offline analysis of the EEG signals (18 bipolar EEG channels of four able-bodied subjects showed that the proposed method acquires low false positive rates at a reasonably high true positive rate. The results also show that features selected from different channels varied considerably from one subject to another. Conclusion The proposed hybrid method effectively reduces the high dimensionality of the feature space. The variability in features among subjects indicates that a user-customized BI system needs to be developed for individual users.

  5. The PACE Study: A randomised clinical trial of cognitive activity (CA for older adults with mild cognitive impairment (MCI

    Directory of Open Access Journals (Sweden)

    Flicker Leon

    2009-12-01

    Full Text Available Abstract Background Research evidence from observational studies suggests that cognitive activity reduces the risk of cognitive impairment in later life as well as the rate of cognitive decline of people with dementia. The Promoting Healthy Ageing with Cognitive Exercise (PACE study has been designed to determine whether a cognitive activity intervention decreases the rate of cognitive decline amongst older adults with mild cognitive impairment (MCI. Methods/Design The study will recruit 160 community-dwelling men and women aged 65 years of age or over with mild cognitive impairment (MCI. Participants will be randomly allocated to two treatment groups: non-specific education and cognitive activity. The intervention will consist of ten 90-minute sessions delivered twice per week over a period of five weeks. The primary outcome measure of the study is the change from baseline in the total score on the Cambridge Cognitive Score (CAMCOG. Secondary outcomes of interest include changes in memory, attention, executive functions, mood and quality of life. Primary endpoints will be collected 12, 52 and 104 weeks after the baseline assessment. Discussion The proposed project will produce the best available evidence on the merits of increased cognitive activity as a strategy to prevent cognitive decline among older adults with MCI. We anticipate that the results of this study will have implications for the development of evidence-based preventive strategies to reduce the rate of cognitive decline amongst older people at risk of dementia. Trial registration ACTRN12608000556347

  6. Head-to-head comparison of dipyridamole, dobutamine and pacing stress echocardiography for the detection of myocardial ischemia in an animal model of coronary artery stenosis

    Directory of Open Access Journals (Sweden)

    A. Schmidt

    2001-07-01

    Full Text Available To compare the sensitivity of dipyridamole, dobutamine and pacing stress echocardiography for the detection of myocardial ischemia we produced a physiologically significant stenosis in the left circumflex artery of 14 open-chest dogs (range: 50 to 89% reduction in luminal diameter. In each study, dobutamine (5 to 40 µg kg-1 min-1 in 3-min stages and pacing (20 bpm increments, each 2 min, up to 260 bpm were performed randomly, and then followed by dipyridamole (up to 0.84 mg/kg over 10 min. The positivity of stress echocardiography tests was quantitatively determined by a significant (P<0.05 reduction of or failure to increase absolute and percent systolic wall thickening in the stenotic artery supplied wall, as compared to the opposite wall (areas related to the left anterior descending artery. Systolic and diastolic frozen images were analyzed off-line by two blinded observers in the control and stress conditions. The results showed that 1 the sensitivity of dobutamine, dipyridamole and pacing stress tests was 57, 57 and 36%, respectively; 2 in animals with positive tests, the mean percent change of wall thickening in left ventricular ischemic segments was larger in the pacing (-19 ± 11% and dipyridamole (-18 ± 16% tests as compared to dobutamine (-9 ± 6% (P = 0.05, but a similar mean reduction of wall thickening was observed when this variable was normalized to a control left ventricular segment (area related to the left anterior descending artery (pacing: -16 ± 7%; dipyridamole: -25 ± 16%; dobutamine: -26 ± 10%; not significant, and 3 a significant correlation was observed between magnitude of coronary stenosis and left ventricular segmental dysfunction induced by ischemia in dogs submitted to positive stress tests. We conclude that the dobutamine and dipyridamole stress tests showed identical sensitivities for the detection of myocardial ischemia in this one-vessel disease animal model with a wide range of left circumflex artery

  7. Stem cell Transplantation for Eradication of Minimal PAncreatic Cancer persisting after surgical Excision (STEM PACE Trial, ISRCTN47877138): study protocol for a phase II study

    International Nuclear Information System (INIS)

    Pancreatic cancer is the third most common cancer related cause of death. Even in the 15% of patients who are eligible for surgical resection the outlook is dismal with less than 10% of patients surviving after 5 years. Allogeneic hematopoietic (allo-HSCT) stem cell transplantation is an established treatment capable of to providing cure in a variety of hematopoietic malignancies. Best results are achieved when the underlying neoplasm has been turned into a stage of minimal disease by chemotherapy. Allo-HSCT in advanced solid tumors including pancreatic cancer have been of limited success, however studies of allo-HSCT in solid tumors in minimal disease situations have never been performed. The aim of this trial is to provide evidence for the clinical value of allo-HSCT in pancreatic cancer put into a minimal disease status by effective surgical resection and standard adjuvant chemotherapy. The STEM PACE trial is a single center, phase II study to evaluate adjuvant allogeneic hematopoietic stem cell transplantation in pancreatic cancer after surgical resection. The study will evaluate as primary endpoint 2 year progression free survival and will generate first time state-of-the-art scientific clinical evidence if allo-HSCT is feasible and if it can provide long term disease control in patients with effectively resected pancreatic cancer. Screened eligible patients after surgical resection and standard adjuvant chemotherapy with HLA matched related stem cell donor can participate. Patients without a matched donor will be used as a historical control. Study patients will undergo standard conditioning for allo-HSCT followed by transplantation of allogeneic unmanipulated peripheral blood stem cells. The follow up of the patients will continue for 2 years. Secondary endpoints will be evaluated on 7 postintervention visits. The principal question addressed in this trial is whether allo-HSCT can change the unfavourable natural course of this disease. The underlying

  8. Evaluation of a New Mixed-Phase Cloud Microphysics Parameterization with CAM3 Single-Column Model and M-PACE Observations

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaohong; Xie, Shaocheng; Ghan, Steven J.

    2007-12-14

    Most global climate models generally prescribe the partitioning of condensed water into liquid droplets and ice crystals in mixed-phase clouds according to a temperature-dependent function, which affects modeled cloud phase, cloud lifetime and radiative properties. This study evaluates a new mixed-phase cloud microphysics parameterization (for ice nucleation and water vapor deposition) against the Atmospheric Radiation Measurement (ARM) Mixed-phase Arctic Cloud Experiment (M-PACE) observations using the NCAR Community Atmospheric Model Version 3 (CAM3) single column model (SCAM). It is shown that SCAM with the new scheme produces a more realistic simulation of the cloud phase structure and the partitioning of condensed waterinto liquid droplets against observations during the M-PACE than the standard CAM. Sensitivity test indicates that ice number concentration could play an important role in the simulated mixed-phase cloud microphysics, and thereby needs to be realistically represented in global climate models.

  9. Evaluation of a new mixed-phase cloud microphysics parameterization with CAM3 single-column model and M-PACE observations

    Science.gov (United States)

    Liu, Xiaohong; Xie, Shaocheng; Ghan, Steven J.

    2007-12-01

    Most global climate models generally prescribe the partitioning of condensed water into cloud droplets and cloud ice in mixed-phase clouds according to a temperature-dependent function, which affects modeled cloud phase, cloud lifetime and radiative properties. This study evaluates a new mixed-phase cloud microphysics parameterization (for ice nucleation and water vapor deposition) against the Atmospheric Radiation Measurement (ARM) Mixed-phase Arctic Cloud Experiment (M-PACE) observations using the NCAR Community Atmospheric Model Version 3 (CAM3) single column model (SCAM). It is shown that SCAM with the new scheme produces a more realistic simulation of the cloud phase structure and the partitioning of condensed water into liquid droplets against observations during the M-PACE than the standard SCAM. A sensitivity test indicates that ice number concentration could play an important role in the simulated mixed-phase cloud microphysics, and therefore needs to be realistically represented in global climate models.

  10. Syndrome of diminished vasodilator reserve of the coronary microcirculation (microvascular angina or syndrome X): Diagnosis by combined atrial pacing and thallium 201 imaging--a case report

    Energy Technology Data Exchange (ETDEWEB)

    Magarian, G.J.; Palac, R.; Reinhart, S. (Veterans Administration Medical Center, Portland, OR (USA))

    1990-08-01

    Patients with angina-like chest pain without evidence of epicardial coronary artery disease or coronary arterial vasospasm are becoming increasingly recognized. These are often related to noncardiac causes including esophageal, musculoskeletal, and hyperventilatory or panic states. However, recently a subgroup of such patients are being recognized as having true myocardial ischemia and chest pain on the basis of diminished coronary microvascular vasodilatory reserve (microvascular ischemia or Syndrome X). The authors describe such a patient who was found to have replication of anginal pain associated with a reversible ischemic defect on thallium 201 imaging during atrial pacing, suggesting ischemia in this myocardial segment. Resolution of angina and ST segment electrocardiographic changes of ischemia occurred with cessation of pacing. We believe this is the first report of a patient with this form of myocardial ischemia diagnosed by this method and should be considered in patients with anginal chest pain after significant coronary artery disease and coronary vasospasm have been excluded.

  11. Syndrome of diminished vasodilator reserve of the coronary microcirculation (microvascular angina or syndrome X): Diagnosis by combined atrial pacing and thallium 201 imaging--a case report

    International Nuclear Information System (INIS)

    Patients with angina-like chest pain without evidence of epicardial coronary artery disease or coronary arterial vasospasm are becoming increasingly recognized. These are often related to noncardiac causes including esophageal, musculoskeletal, and hyperventilatory or panic states. However, recently a subgroup of such patients are being recognized as having true myocardial ischemia and chest pain on the basis of diminished coronary microvascular vasodilatory reserve (microvascular ischemia or Syndrome X). The authors describe such a patient who was found to have replication of anginal pain associated with a reversible ischemic defect on thallium 201 imaging during atrial pacing, suggesting ischemia in this myocardial segment. Resolution of angina and ST segment electrocardiographic changes of ischemia occurred with cessation of pacing. We believe this is the first report of a patient with this form of myocardial ischemia diagnosed by this method and should be considered in patients with anginal chest pain after significant coronary artery disease and coronary vasospasm have been excluded

  12. The CNRS and the nuclear wastes management. Contribution to the program on the electronuclear cycle downstream PACE at the law of the 30 December 1991

    International Nuclear Information System (INIS)

    This document is a presentation of the activities of the PACE program. It presents the researches historical aspects, the researches concerning the axis 1 (transmutation, nuclear data acquisition, scenarios, separation and physico-chemistry in homogenous solution, the specific conditioning) and the axis 2 researches (the containment safety studies of the underground disposal, the physico-chemical phenomenons at the interfaces, the radionuclides migration). (A.L.B.)

  13. Correlates of quitting the Paced Auditory Serial Addition Test in cognitively normal older adults participating in a study of normal cognitive aging

    OpenAIRE

    Locke, Dona E.C.; Stonnington, Cynthia M.; Thomas, Michael L.; Caselli, Richard J.

    2011-01-01

    Our study of cognitive aging involves a comprehensive battery of neuropsychological measures. The Paced Auditory Serial Addition Test (PASAT) is the only test that some of our participants will refuse to complete. We explored variables related to quitting versus completing the PASAT in this sample of normal older adults. We hypothesized that quitting would be related to personality features, subclinical anxiety symptoms, demographics, and/or Wechsler Adult Intelligence Scale–Revised (WAIS–R) ...

  14. Spectral analysis of respiratory-related hemodynamic variables in simulated hypovolemia: a study in healthy volunteers with spontaneous breathing using a paced breathing activity

    OpenAIRE

    Shin, Won Jung; Choi, Jae Moon; Kong, Yu Gyeong; Song, Jun Gol; Kim, Young Kug; Hwang, Gyu Sam

    2010-01-01

    Background A dynamic preload index such as stroke volume variation (SVV) is not as reliable in spontaneous breathing (SB) patients as in mechanically ventilated patients. This study examined the hypothesis that spectral analysis of hemodynamic variables during paced breathing (PB) activity may be a feasible index of volume changes and fluid responsiveness, despite insufficient respiratory changes in the preload index during SB activity. Methods Blood pressure and stroke volume (SV) were measu...

  15. A comparison of sympathoadrenal activity and cardiac performance at rest and during exercise in patients with ventricular demand or atrial synchronous pacing.

    OpenAIRE

    Pehrsson, S K; Hjemdahl, P; Nordlander, R; Aström, H

    1988-01-01

    Cardiac sympathetic function was assessed by measuring the coronary sinus overflow of noradrenaline and dopamine at rest and during supine exercise in eight patients with high degree atrioventricular block treated with dual chamber pacemakers (DDD). Patients exercised (30-60 W) during both ventricular inhibited (VVI) and atrial synchronous (VAT) pacing. During exercise cardiac output increased less markedly in the VVI mode than in the VAT mode. The cardiac output response was entirely stroke ...

  16. Effect of increasing heart rate in patients with aortic regurgitation. Effect of incremental atrial pacing on scintigraphic, hemodynamic and thermodilution measurements

    Energy Technology Data Exchange (ETDEWEB)

    Firth, B.G.; Dehmer, G.J.; Nicod, P.; Willerson, J.T.; Hillis, L.D.

    1982-06-01

    This study was performed to assess the effect of pacing-induced tachycardia in patients with aortic regurgitation. In 12 patients (5 men and 7 women with a mean age of 53 years) with aortic regurgitation, left ventricular end-diastolic and end-systolic volume indexes were measured with multigated equilibrium blood pool imaging, and forward cardiac index was determined with thermodilution, both at rest (mean heart rate +/- standard deviation 72 +/- 8 beats/min) and during atrial pacing at 100 and 120 beats/min. Pacing caused a decremental reduction in left ventricular end-diastolic and end-systolic volume indexes and radionuclide-determined stroke volume index but no change in radionuclide-determined cardiac index or left ventricular ejection fraction. Forward cardiac index increased incrementally from the baseline value at rest to that at 120 beats/min despite a decremental reduction in stroke volume index. There was a stepwise decrease in regurgitant volume/stroke (46 +/- 20 ml/m2 at baseline, 27 +/- 15 at 120 beats/min; p less than 0.05) but no change in regurgitant volume/min (3.38 +/- 1.80 liters/min per m2 at baseline, 3.22 +/- 1.78 at 120 beats/min; difference not significant (NS)) or regurgitant fraction (0.54 +/- 0.13 at baseline, 0.49 +/- 0.13 at 120 beats/min; NS). Mean femoral arterial, pulmonary arterial and pulmonary capillary wedge pressures did not change with pacing.

  17. How do children deal with inconsistencies in text? An eye fixation and self-paced reading study in good and poor reading comprehenders

    OpenAIRE

    van der Schoot, Menno; Reijntjes, Albert; van Lieshout, Ernest C. D. M.

    2011-01-01

    In two experiments, we investigated comprehension monitoring in 10–12 years old children differing in reading comprehension skill. The children’s self-paced reading times (Experiment 1) and eye fixations and regressions (Experiment 2) were measured as they read narrative texts in which an action of the protagonist was consistent or inconsistent with a description of the protagonist’s character given earlier. The character description and action were adjacent (local condition) or separated by ...

  18. Right versus left atrial pacing in patients with sick sinus syndrome and paroxysmal atrial fibrillation (Riverleft study): study protocol for randomized controlled trial

    OpenAIRE

    Ramdjan, Tanwier TTK; van der Does, Lisette JME; Knops, Paul; Res, Jan CJ; de Groot, Natasja MS

    2014-01-01

    Background The incidence of sick sinus syndrome will increase due to population ageing. Consequently, this will result in an increase in the number of pacemaker implantations. The atrial lead is usually implanted in the right atrial appendage, but this position may be ineffective for prevention of atrial fibrillation. It has been suggested that pacing distally in the coronary sinus might be more successful in preventing atrial fibrillation episodes. The aim of this trial is to study the effic...

  19. Methodology for Process Improvement Through Basic Components and Focusing on the Resistance to Change.

    OpenAIRE

    Calvo-Manzano Villalon, Jose Antonio; Cuevas Agustin, Gonzalo; Gómez, Gerzón; Mejia, Jezreel; Muñoz, Mirna; San Feliu Gilabert, Tomas

    2010-01-01

    This paper describes a multi-model methodology that implements a smooth and continuous process improvement, depending on the organization's business goals and allowing users to establish their improvement implementation pace. The methodology focuses on basic process components known as ‘best practices’. Besides, it covers following the topics: knowledge management and change management. The methodology description and the results of a case study on project management process are included.

  20. Pace of macrophage recruitment during different stages of soft tissue infection: Semi-quantitative evaluation by in vivo magnetic resonance imaging

    International Nuclear Information System (INIS)

    We describe the pace of recruitment of iron-oxide-labeled macrophages to the site of different stages of infection by in vivo magnetic resonance (MR) imaging. Peritoneal macrophages were labeled with superparamagnetic iron oxide ex vivo and administered through the tail vein 6 (acute) or 48 (subacute) h after bacterial inoculation. The legs of the mice were imaged sequentially on a 4.7-T MR unit before and 3, 6, 12, 18, 24, 48 and 72 h after macrophage administration. The band-shaped lower signal intensity zone around the abscess on T2*-weighted GRE images became more obvious due to recruited macrophages up until 24 h after injection in the subacute and 48 h after injection in the acute group, indicating that the relative SI of the abscess wall decreased more rapidly and the pace of recruitment of macrophages was faster in the subacute than in the acute group. Chemokine antibody arrays of mouse sera detected increased concentration of granulocyte-colony-stimulating factor and tissue inhibitor of metalloproteinase-1 beginning at 12 h and increased interleukin-13 at 18 h. Monocyte chemoattractant protein-1 and macrophage-colony-stimulating factor began to increase at 96 h after infection. This difference in pace of recruitment may result from the release of chemokines. (orig.)

  1. A "one size fits all" approach to language fMRI: increasing specificity and applicability by adding a self-paced component.

    Science.gov (United States)

    Máté, Adrienn; Lidzba, Karen; Hauser, Till-Karsten; Staudt, Martin; Wilke, Marko

    2016-03-01

    We have previously established an fMRI task battery suitable for mapping the language processing network in children. Among the tasks used, the synonyms and the vowel identification task induced robust task-related activations in children with average language abilities; however, the fixed presentation time seems to be a drawback in participants with above- or below-average language abilities. This feasibility study in healthy adults (n = 20) was aimed at adapting these tasks to the individual level of each patient by implementing a self-paced stimulus presentation. The impact of using a block- versus an event-related statistical approach was also evaluated. The self-paced modification allowed our participants with above-average language abilities to process stimuli much faster than originally implemented, likely increasing task adherence. A higher specificity of the event-related analysis was confirmed by stronger left inferior frontal and crossed cerebellar activations. We suggest that self-paced paradigms and event-related analyses may both increase specificity and applicability. PMID:26514810

  2. Immunoendocrine responses of male spinal cord injured athletes to 1-hour self-paced exercise: Pilot study

    Directory of Open Access Journals (Sweden)

    Judith E. Allgrove, PhD

    2012-08-01

    Full Text Available This study examined the effect of a 1 h, self-paced handcycling time trial on blood leukocytes, mucosal immunity, and markers of stress in paraplegic athletes. Nine male paraplegic athletes (spinal injury level thoracic 4–lumbar 2 performed 1 h of handcycling exercise on a standard 400 m athletics track. Heart rate (HR was measured continuously during exercise, and a retrospective rating of perceived exertion (RPE was obtained immediately after. Venous blood and saliva samples were collected immediately before exercise (Pre-Ex, after exercise (End-Ex, and 1 h postexercise (1-h Post. The athletes completed mean +/– standard error of mean 22.4 +/– 1.1 km cycling at HR 165 +/– 2 beats/min, RPE 15 +/– 1, and blood lactate 7.9 +/– 2.5 mmol/L. Total leukocytes increased 72% and neutrophils increased 74% End-Ex; both remained elevated at 1-h Post (both p < 0.05. Lymphocytes increased 53% and natural killer cells increased 175% End-Ex (both p < 0.05, but returned to near baseline levels 1-h Post. Increases (p < 0.05 were observed End-Ex in alpha-amylase activity (p < 0.05, which returned to baseline at 1-h Post, but there was no significant change in saliva flow rate, salivary immunoglobulin A, or cortisol. These data confirm that 1 h of handcycling exercise elevated circulating leukocytes but had a minimal effect on mucosal immunity. These changes appear to be associated with alpha-amylase rather than cortisol.

  3. Evaluation of a dual sensor rate responsive pacing system based on a new concept. French Talent DR Pacemaker Investigators.

    Science.gov (United States)

    Bonnet, J L; Géroux, L; Cazeau, S

    1998-11-01

    The minute ventilation is known to be one of the most physiological indicators of exercise. A curvilinear relationship between VE and the normal sinus rhythm (NSR) has been demonstrated in healthy patients. The aim of this study is to show that a pacemaker based on a VE sensor can reproduce such a relationship. Eighty-one patients received a Talent DR 213 (ELA Medical, Montrouge, France) pacemaker with a third-generation rate responsive algorithm. At 1-month follow-up, the patients underwent a treadmill exercise test, after which three groups were defined: group 1 had 6 patients who were 100% paced throughout the exercise test; group 2 had 10 patients who maintained NSR throughout the test; and group 3 had 12 patients who had cardiopulmonary recording during the exercise test. In group 1 patients, the simulation function computed the simulated rate (sim-rate), which was compared to the sensor-driven rate (SDR). In group 2 patients, sim-rate was compared to the NSR. In group 3 patients, cardiac and metabolic reserves were compared to determine the appropriateness of the rate response to exercise (HRR% vs MR%). The results showed that the mean correlation coefficient between sim-rate and SDR was 0.983 +/- 0.005 (P < 0.001); the mean correlation coefficient between NSR and SDR was 0.92 +/- 0.07 (P < 0.001); and a linear relationship was found between HRR% and MR%, with a mean slope of 1.1 +/- 0.2 that was significantly equal to the theoretical value of 1 (P = NS). In conclusion, combining an activity-driven sensor with a physiological sensor allows the preservation of a physiological rate response during exercise. PMID:9825318

  4. Representing number in the real-time processing of agreement: Self-paced reading evidence from Arabic

    Directory of Open Access Journals (Sweden)

    Matthew A. Tucker

    2015-04-01

    Full Text Available In the processing of subject-verb agreement, non-subject plural nouns following a singular subject sometimes attract the agreement with the verb, despite not being grammatically licensed to do so. This phenomenon generates agreement errors in production and an increased tendency to fail to notice such errors in comprehension, thereby providing a window into the representation of grammatical number in working memory during sentence processing. Research in this topic, however, is primarily done in related languages with similar agreement systems. In order to increase the cross-linguistic coverage of the processing of agreement, we conducted a self-paced reading study in Modern Standard Arabic. We report robust agreement attraction errors in relative clauses, a configuration not particularly conducive to the generation of such errors for all possible lexicalizations. In particular, we examined the speed with which readers retrieve a subject controller for both grammatical and ungrammatical agreeing verbs in sentences where verbs are preceded by two NPs, one of which is a local non-subject NP that can act as a distractor for the successful resolution of subject-verb agreement. Our results suggest that the frequency of errors is modulated by the kind of plural formation strategy used on the attractor noun: nouns which form plurals by suffixation condition high rates of attraction, whereas nouns which form their plurals by internal vowel change (ablaut generate lower rates of errors and reading-time attraction effects of smaller magnitudes. Furthermore, we show some evidence that these agreement attraction effects are mostly contained in the right tail of reaction time distributions. We also present modeling data in the ACT-R framework which supports a view of these ablauting patterns wherein they are differentially specified for number and evaluate the consequences of possible representations for theories of grammar and parsing.

  5. Animal personality and pace-of-life syndromes: do fast-exploring fairy-wrens die young?

    Directory of Open Access Journals (Sweden)

    Michelle L Hall

    2015-03-01

    Full Text Available The pace-of-life syndrome (POLS hypothesis for animal personality proposes that variation among individuals in life-history strategies is associated with consistent differences in behavior. We tested predictions of this hypothesis in the superb fairy-wren, Malurus cyaneus, by investigating long-term individual differences in risk-related behaviors (latency to enter a novel artificial environment, exploration, activity and response to mirror image stimulation and survival. We found consistent differences between individuals in these behaviors (adjusted repeatability of exploration of artificial novel environment = 0.37. Individual differences were consistent over several years and bi-variate analyses showed a significant among-individual correlation (‘behavioral syndrome’ between exploration behavior at two life stages (young adult and old adult. Docility at the nestling stage predicted exploration behavior of juveniles. Behavioral traits measured in a risky context were correlated with one another, forming a behavioral syndrome of coping strategies ranging from ‘proactive’ to ‘reactive’. Nestlings that were more active and exploratory in isolation were less docile during handling, while adults that entered the artificial environment fast were more exploratory, active, and aggressive in the artificial environment. Exploration behavior increased within individuals as they aged and when they were in poorer condition, consistent with expectations of more risk-prone behavior with lower residual reproductive value (reduced ‘asset protection’. Risk-related behavior predicted the probability of apparent survival: more exploratory individuals were less likely to be present in the population twelve months later. Our findings suggest that, consistent with the predictions of the POLS hypothesis, individual variation in survival is associated with consistent individual differences in risk-related behavior that are maintained long-term and

  6. The PACE-1450 experiment - Crack and leakage behavior of a pre-stressed concrete containment wall considering ageing

    International Nuclear Information System (INIS)

    As an intermediate sized experiment the PACE-1450 experiment aims to investigate the behavior of a curved specimen (length: 3.5 m, width: 1.8 m, height: 1.2 m) which is representative for a 1450 MWe nuclear power plant containment under accidental loading conditions. One focus of this experimental test campaign is the consideration of the ageing of the structure which among other effects leads to a pre-stressing loss. The crack behavior of the realistically reinforced specimen is of as much interest as it is the leakage behavior when an inner pressure occurs within the containment. The reinforcement layout of the specimen is very similar to the original geometry and consists mainly of reinforcement meshes of bars near the inner and outer surface and four pre-stressing cables in the circumferential direction. During the tests the specimen is loaded by pressure which simulates the internal accidental containment pressure of up to 6 bars (absolute pressure). The resulting ring tensile stress in the cylindrical part of the containment is externally applied by hydraulic jacks. An initial pre-stressing of the specimen of 12 MPa is realized in such a way that decreasing the pre-stressing force for the purpose of simulating the ageing of the structure is possible. The facility allows for the cracking of the pre-stressed specimen and for leakage measurements at different controlled crack widths. The specimen is equipped with embedded optical fiber strain and temperature sensors and a sound detection system to record the initiation of cracks. The paper explains the test set-up and presents results of the ongoing test series regarding the cracking and leakage behavior of the specimen

  7. Enhancing Cardiac Resynchronization Therapy for Patients with Atrial Fibrillation: The Role of AV Node Ablation

    Directory of Open Access Journals (Sweden)

    Jeff M. Berry, MD

    2012-04-01

    Full Text Available Cardiac resynchronization therapy (CRT has evolved as an effective therapy for patients with congestive heart failure (CHF and ventricular dyssynchrony, currently defined as a wide QRS on the electrocardiogram. While multiple randomized controlled trials have confirmed the favorable effects of CRT on mortality and heart failure symptoms for patients in sinus rhythm, only recently observational studies have begun to suggest a similar benefit for patients with atrial fibrillation (AF and dyssynchrony. Yet, implementing effective biventricular pacing in patients with AF can be problematic due to competing intrinsic AV conduction. For patients with depressed ejection fractions needing AV node (AVN ablation to control fast ventricular rates, biventricular pacing has been shown to be superior to right ventricular pacing alone. When consistent pacing (over 90% of the time cannot be achieved in AF patients due to a rapid ventricular response despite pharmacological therapy, AVN ablation should be considered. The additional benefit of performing AVN ablation to promote biventricular pacing in patients without rapid ventricular rates remains uncertain. A randomized controlled trial is needed to test the incremental benefit of AVN ablation to promote biventricular pacing in heart failure patients with AF and wide QRS.

  8. Change of Cardiovascular Variability During a Stepwise Paced Breathing Procedure%渐进性引导呼吸下的心血管变异性分析

    Institute of Scientific and Technical Information of China (English)

    张政波; 王步青; 柴晓珂; 郑捷文; 王卫东; 吴昊; 李开元; 刘洪运

    2014-01-01

    研究了引导呼吸下心血管参数变化情况,观察引导呼吸对心血管系统的累积作用效果。采用了呼吸率由高到低渐进性变化的呼吸运动模板,同步观察了心率变异性、血压和脉搏波传导时间的变化规律。实验结果表明,在渐进性引导呼吸过程中,随着呼吸率的降低,呼吸运动对心率、血压和脉搏波传导时间的幅度调制作用显著增强(p<0.05),同时脉搏波传导时间延长,血压下降。该引导呼吸模式具有显著降低血压的作用效果(p<0.05),脉搏波传导时间基线可作为一个有效的指标来表征引导呼吸的作用效果。%To investigate the effect of paced breathing on cardiovascular system, the cardiovascular variables of heart rate, blood pressure and pulse transit time (PTT) were measured during a stepwise paced breathing procedure (six different breathing rates at [14, 12.5, 11, 9.5, 8, 7]BPM). Respiratory sinus arrhythmia (RSA) was estimated by using autoregressive (AR) model based power spectral analysis. The ensemble empirical mode decomposition (EEMD) was applied to PTT to decompose the signal into different intrinsic mode function, and respiration-derived oscillation and trend component (baseline) in PTT were extracted for further analysis. The results clearly indicate that the stepwise paced breathing procedure can induce increased oscillations in RSA, blood pressure and PTT, meanwhile, reduce blood pressure and lengthen PTT baseline. It was demonstrated that this stepwise paced breathing procedure can lead to blood pressure reduction significantly (p<0.05), and PTT can be used as a maker for the effect of paced breathing on cardiovascular system.

  9. CHADS2 and CHA2DS2-VASc score to assess risk of stroke and death in patients paced for sick sinus syndrome

    Science.gov (United States)

    Svendsen, Jesper Hastrup; Nielsen, Jens Cosedis; Darkner, Stine; Jensen, Gunnar Vagn Hagemann; Mortensen, Leif Spange; Andersen, Henning Rud

    2013-01-01

    Objective The risk of stroke in patients with atrial fibrillation (AF) can be assessed by use of the CHADS2 and the CHA2DS2-VASc score system. We hypothesised that these risk scores and their individual components could also be applied to patients paced for sick sinus syndrome (SSS) to evaluate risk of stroke and death. Design Prospective cohort study. Settings All Danish pacemaker centres and selected centres in the UK and Canada. Patients Risk factors were recorded prior to pacemaker implantation in 1415 patients with SSS participating in the Danish Multicenter Randomized Trial on Single Lead Atrial Pacing versus Dual Chamber Pacing in Sick Sinus Syndrome (Danpace) trial. Development of stroke was assessed at follow-up visits and by evaluation of patient charts. Mortality was assessed from the civil registration system. Interventions Patients were randomised to AAIR (N=707) or DDDR pacing (N=708). Main outcome measures Stroke and death during follow-up. Results Mean follow-up was 4.3±2.5 years. In the AAIR group 6.9% patients developed stroke versus 6.1% in the DDDR group (NS). There was a significant association between CHADS2 score and the development of stroke (HR 1.41; 95% CI 1.22 to 1.64, p<0.001). CHA2DS2-VASc score was also significantly associated with stroke (HR 1.25; CI 1.12 to 1.40, p<0.001). CHADS2 score (HR 1.46; CI 1.36 to 1.56, p<0.001) and CHA2DS2-VASc score (HR 1.39; CI 1.31 to 1.46, p<0.001) were associated with mortality. Results were still significant after adjusting for AF and anticoagulation therapy. Conclusions CHADS2 and CHA2DS2-VASc score are associated with increased risk of stroke and death in patients paced for SSS irrespective of the presence of AF. PMID:23539553

  10. Utility of a Novel Biofeedback Device for Within-Breath Modulation of Heart Rate in Rats: A Quantitative Comparison of Vagus Nerve vs. Right Atrial Pacing.

    Science.gov (United States)

    O'Callaghan, Erin L; Chauhan, Ashok S; Zhao, Le; Lataro, Renata M; Salgado, Helio C; Nogaret, Alain; Paton, Julian F R

    2016-01-01

    In an emerging bioelectronics era, there is a clinical need for physiological devices incorporating biofeedback that permits natural and demand-dependent control in real time. Here, we describe a novel device termed a central pattern generator (CPG) that uses cutting edge analog circuitry producing temporally controlled, electrical stimulus outputs based on the real time integration of physiological feedback. Motivated by the fact that respiratory sinus arrhythmia (RSA), which is the cyclical changes in heart rate every breath, is an essential component of heart rate variability (HRV) (an indicator of cardiac health), we have explored the versatility and efficiency of the CPG for producing respiratory modulation of heart rate in anesthetized, spontaneously breathing rats. Diaphragmatic electromyographic activity was used as the input to the device and its output connected to either the right cervical vagus nerve or the right atrium for pacing heart rate. We found that the CPG could induce respiratory related heart rate modulation that closely mimicked RSA. Whether connected to the vagus nerve or right atrium, the versatility of the device was demonstrated by permitting: (i) heart rate modulation in any phase of the respiratory cycle, (ii) control of the magnitude of heart rate modulation, and (iii) instant adaptation to changes in respiratory frequency. Vagal nerve pacing was only possible following transection of the nerve limiting its effective use chronically. Pacing via the right atrium permitted better flexibility and control of heart rate above its intrinsic level. This investigation now lays the foundation for future studies using this biofeedback technology permitting closer analysis of both the function and dysfunction of RSA. PMID:26869940

  11. Utility of a novel biofeedback device for within-breath modulation of heart rate in rats: a quantitative comparison of vagus nerve versus right atrial pacing.

    Directory of Open Access Journals (Sweden)

    Erin Louise O'Callaghan

    2016-02-01

    Full Text Available In an emerging bioelectronics era, there is a clinical need for physiological devices incorporating biofeedback that permits natural and demand-dependent control in real time. Here, we describe a novel device termed a central pattern generator (CPG that uses cutting edge analogue circuitry producing temporally controlled, electrical stimulus outputs based on the real time integration of physiological feedback. Motivated by the fact that respiratory sinus arrhythmia (RSA, which is the cyclical changes in heart rate every breath, is an essential component of heart rate variability (an indicator of cardiac health, we have explored the versatility and efficiency of the CPG for producing respiratory modulation of heart rate in anaesthetised, spontaneously breathing rats. Diaphragmatic electromyographic activity was used as the input to the device and its output connected to either the right cervical vagus nerve or the right atrium for pacing heart rate. We found that the CPG could induce respiratory related heart rate modulation that closely mimicked RSA. Whether connected to the vagus nerve or right atrium, the versatility of the device was demonstrated by permitting: (i heart rate modulation in any phase of the respiratory cycle, (ii control of the magnitude of heart rate modulation and (iii instant adaptation to changes in respiratory frequency. Vagal nerve pacing was only possible following transection of the nerve limiting its effective use chronically. Pacing via the right atrium permitted better flexibility and control of heart rate above its intrinsic level. This investigation now lays the foundation for future studies using this biofeedback technology permitting closer analysis of both the function and dysfunction of RSA.

  12. Effects of retained guidewire on pacing lead%保留导丝技术对起搏导线的影响

    Institute of Scientific and Technical Information of China (English)

    林若薇; 李晓宏; 吉文庆; 徐伟

    2015-01-01

    目的 总结因保留导丝至起搏导线断裂的病例,观察保留导丝对起搏导线的影响 方法 观察了自2010年1月至2013年12月因导线断裂在南京鼓楼医院行导线拔除的患者6例,其中5例采用了保留导丝技术.结果 5例患者均成功拔除了导线.2根右心室主动固定导线的保留钢丝及导线内部线圈均断裂,断裂处在锁骨下静脉.2例左心室导线的保留导丝及导线线圈均断裂,断裂部位在三尖瓣环,1例左心室导线仅保留导丝断裂,但内部线圈仍完整,测试导线阻抗未见明显升高.结论 保留导丝可损伤导线绝缘层及内部线圈,建议慎用保留导丝技术.%Objective Observe the influence of retained guidewire on the pacing lead.Methods From Jan.2010 to Dec.2013,Nanjing Drum Tower Hospital,six patients received leads extraction because of lead fracture were enrolled in our study.Results Five patients had retained guidewire.All leads were extracted using mechanical tools,including 2 right ventricular fixed leads and 3 left ventricular pacing leads.Fracture of the coil electrodes as well as deterioration of the insulation coating was found in 4 patients.1 retained guide in left ventricular pacing fracture,but the pacing parameters,including impedance was not elevated.Conclusion The retained guidewire technique should not be used because delayed electrode damage can occur.

  13. CHADS2 and CHA2DS2-VASc score to assess risk of stroke and death in patients paced for sick sinus syndrome

    OpenAIRE

    Svendsen, Jesper Hastrup; Nielsen, Jens Cosedis; Darkner, Stine; Jensen, Gunnar Vagn Hagemann; Mortensen, Leif Spange; Andersen, Henning Rud; . .

    2013-01-01

    Objective The risk of stroke in patients with atrial fibrillation (AF) can be assessed by use of the CHADS2 and the CHA2DS2-VASc score system. We hypothesised that these risk scores and their individual components could also be applied to patients paced for sick sinus syndrome (SSS) to evaluate risk of stroke and death. Design Prospective cohort study. Settings All Danish pacemaker centres and selected centres in the UK and Canada. Patients Risk factors were recorded prior to pacemaker implan...

  14. Pacemaker Prevention Therapy in Drug-refractory Paroxysmal Atrial Fibrillation: Reliability of Diagnostics and Effectiveness of Prevention Pacing Therapy in Vitatron™ Selection® Device

    OpenAIRE

    2006-01-01

    Introduction. Atrial fibrillation (AF), the most common and rising disorder of cardiac rhythm, is quite difficult to control and/or to treat. Non pharmacological therapies for AF may involve the use of dedicated pacing algorithms to detect and prevent atrial arrhythmia that could be a trigger for AF onset. Selection 900E/AF2.0 Vitatron DDDRP pacemaker (1) keeps an atrial arrhythmia diary thus providing detailed onset reports of arrhythmias of interest, (2) provides us data about the number of...

  15. Fetal cardiac interventions: clinical and experimental research.

    Science.gov (United States)

    Yuan, Shi-Min; Humuruola, Gulimila

    2016-01-01

    Fetal cardiac interventions for congenital heart diseases may alleviate heart dysfunction, prevent them evolving into hypoplastic left heart syndrome, achieve biventricular outcome and improve fetal survival. Candidates for clinical fetal cardiac interventions are now restricted to cases of critical aortic valve stenosis with evolving hypoplastic left heart syndrome, pulmonary atresia with an intact ventricular septum and evolving hypoplastic right heart syndrome, and hypoplastic left heart syndrome with an intact or highly restrictive atrial septum as well as fetal heart block. The therapeutic options are advocated as prenatal aortic valvuloplasty, pulmonary valvuloplasty, creation of interatrial communication and fetal cardiac pacing. Experimental research on fetal cardiac intervention involves technical modifications of catheter-based cardiac clinical interventions and open fetal cardiac bypass that cannot be applied in human fetuses for the time being. Clinical fetal cardiac interventions are plausible for midgestation fetuses with the above-mentioned congenital heart defects. The technical success, biventricular outcome and fetal survival are continuously being improved in the conditions of the sophisticated multidisciplinary team, equipment, techniques and postnatal care. Experimental research is laying the foundations and may open new fields for catheter-based clinical techniques. In the present article, the clinical therapeutic options and experimental fetal cardiac interventions are described. PMID:27279868

  16. Analysis of Improvement on Human Resource Management within Chinese Enterprises in Economic Globalization

    OpenAIRE

    Lihui Xie; Dasong Deng; Xifa Liu

    2013-01-01

    In this study, we analysis of improvement on human resource management within Chinese enterprises in economic globalization. China’s entry into WTO has accelerated the economic globalization pace of Chinese enterprises and Chinese economy is further integrated with the global economy in a global scope. Human resource is what economic globalization of Chinese enterprises relies on, the first resource for China to participate in the international competition and is also the key to make effectiv...

  17. Two-photon excitation improves multifocal structured illumination microscopy in thick scattering tissue

    OpenAIRE

    Ingaramo, Maria; York, Andrew G.; Wawrzusin, Peter; Milberg, Oleg; Hong, Amy; Weigert, Roberto; Shroff, Hari; Patterson, George H.

    2014-01-01

    Superresolution microscopy has made much progress in improving resolution and imaging speed over the past several years, but the ability to image below the diffraction limit in thick scattering specimens has not kept pace. In many interesting samples, such as Caenorhabditis elegans, Drosophila melanogaster, mouse, or human tissues, resolution is limited primarily by scattering rather than diffraction. In this paper, we show that the combination of multiphoton excitation with multifocal struct...

  18. Comparison of energy cost between genders during treadmill walking at a self-selected pace - doi 10.4025/actascihealthsci.v34i2.9333

    Directory of Open Access Journals (Sweden)

    Sergio Gregorio da Silva

    2012-09-01

    Full Text Available The purpose of this study was to compare the energy cost between genders during treadmill walking at self-selected pace; and to verify if the energy cost achieve the values recommended for weight maintenance or loss proposed by the American College of Sports Medicine (ACSM. Seventeen men and seventeen women, mean age of 23.32 ± 3.06 years, undertaken two experimental sessions: (I anthropometric measurements and a load-incremental maximum test; and, (II a 20-min walking test at self-selected pace on treadmill. Men showed a greater energy cost than women (146.18 ± 47.66 and 100.86 ± 17.04 kcal, respectively. This difference was maintained after adjust by body weight (2.2 ± 0.5 and 1.7 ± 0.2 kcal kg-1, respectively. The greater energy cost found in men can be explained by the self-selected treadmill speed that lead to a greater O2 in men. However, the exercise intensity selected by both genders did not elicit an effective energy cost that can promote weight maintenance or loss. Nonetheless, if participants performed a longer walking (> 20 minutes, they probably would achieve the energy cost recommended by the ACSM guidelines.  

  19. Steps towards a CSP yield calculation guideline: A first draft for discussion in the SolarPACES working group guiSmo

    Science.gov (United States)

    Hirsch, Tobias; Bachelier, Camille; Eck, Markus; Dersch, Jürgen; Fluri, Thomas; Giuliano, Stefano; Goebel, Olaf; Haller, Ursula; Lude, Simon; Meyer, Richard; Rau, Christoph; Schenk, Heiko; Schmidt, Norbert; Seitz, Markus; Westphal, Boris; Yildiz, Enver

    2016-05-01

    This paper provides an overview on an important step towards a SolarPACES guideline for CSP yield calculation. With the increasing number of CSP installations, standardization becomes more and more important for further reduction of costs and increase in quality. Yield calculation is a key issue throughout all phases of project development and throughout most of the involved players. Due to the need for more complex process models for CSP compared to other renewables like PV or wind, the yield calculation procedure is more demanding. Uncertainties in the process are covered by additional but partially unnecessary risk surcharges since systematic approaches for avoiding expensive redundancies in risk buffers are not available. It is the main motivation of the mentioned CSP yield calculation guideline to overcome this situation by providing a detailed methodology for yield calculation. A first comprehensive draft version has been compiled and will be subject of discussion in the SolarPACES working group guiSmo. The following sections illustrate the motivation for the guideline, the contents at a glance, as well as expected benefits for selected players.

  20. Análise dos fatores de risco para mortalidade na estimulação pediátrica endocárdica transfemoral: experiência em longo prazo Risk factors analysis in transvenous pediatric pacing through femoral access: long-term experience

    Directory of Open Access Journals (Sweden)

    Roberto Costa

    2005-06-01

    Full Text Available OBJETIVO: A estimulação cardíaca permanente melhora a sobrevida de crianças com bradicardia congênita ou adquirida, embora a mortalidade após o implante de marcapasso permaneça relativamente alta. O objetivo deste estudo foi avaliar os resultados em longo prazo de crianças submetidas a implante de marcapasso endocárdico pela veia femoral, incluindo a identificação de fatores de risco associados à mortalidade. MÉTODO: De 1981 a 2000, 99 pacientes variando em idade de um dia a 13 anos (4,1 ± 3,6 com mediana = 3 anos foram submetidos a implante de marcapasso permanente pela via femoral devido a bradicardia de origem congênita (39,4%, pós-cirúrgica (54,5% ou adquirida não cirurgicamente (6,1%. RESULTADOS: Ao final de 7,1 ± 5,3 anos (708,3 pacientes-anos de seguimento, 18 (18,2% pacientes haviam morrido. A sobrevida atuarial foi de 85%, 79,5%, e 74,2%, aos cinco, 10, e 15 anos, respectivamente. Os fatores independentes de mortalidade identificados pela análise proporcional de Cox foram: menor idade ao implante (p = 0,028, presença de anomalias cardíacas não corrigidas ou presença de próteses intracardíacas (p = 0,0001 e evidências radiográficas de cardiomegalia (p = 0,035. CONCLUSÕES: A estimulação cardíaca endocárdica permanente pela via femoral apresenta expectativa de sobrevida comparável a outras técnicas, com baixas taxas de complicações devidas ao implante de marcapasso. A sobrevida em longo prazo foi limitada pela menor idade e dilatação cardíaca no momento do implante, assim como pela presença de defeitos cardíacos sem correção ou de próteses valvares.OBJECTIVE: Permanent cardiac pacing improves survival of children with congenital or acquired bradycardia, although mortality after pacing remains relatively high. The aim of this study was to evaluate the long-term outcomes of children who undergo permanent endocardial cardiac pacing via the femoral vein, including the identification of associated

  1. Analysis of the Pace University Center for Environmental Legal Studies report of September 1990 entitled, {open_quotes}Environmental costs of electicity{close_quotes} by R.L. Ottinger, D.R. Wooley, N.A. Robinson, D.R. Hodas, Babb, S.E.

    Energy Technology Data Exchange (ETDEWEB)

    Catlin, R.J. [Univ. of Texas, Houston, TX (United States)

    1992-06-01

    This report evaluates the figures used by Pace University in its September 1990 report entitled `Environmental Costs of Electricity` and the conclusions the Pace authors come to using those figures. The data Paces uses in its report is given on pages 379-381 of the US DOE report entitled `Health and Environmental Consequences of the Chernobyl Nuclear Power Plant Accident.` 10 refs., 1 fig., 22 tabs.

  2. The goal a process of ongoing improvement

    CERN Document Server

    Goldratt, Eliyahu M

    2014-01-01

    Written in a fast-paced thriller style, The Goal, a gripping novel, is transforming management thinking throughout the world. It is a book to recommend to your friends in industry - even to your bosses - but not to your competitors. Alex Rogo is a harried plant manager working ever more desperately to try improve performance. His factory is rapidly heading for disaster. So is his marriage. He has ninety days to save his plant - or it will be closed by corporate HQ, with hundreds of job losses. It takes a chance meeting with a professor from student days - Jonah - to help him break out of conventional ways of thinking to see what needs to be done. The story of Alex's fight to save his plant is more than compulsive reading. It contains a serious message for all managers in industry and explains the ideas, which underline the Theory of Constraints (TOC), developed by Eli Goldratt.

  3. Protocol for diaphragm pacing in patients with respiratory muscle weakness due to motor neurone disease (DiPALS: a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    McDermott Christopher J

    2012-08-01

    Full Text Available Abstract Background Motor neurone disease (MND is a devastating illness which leads to muscle weakness and death, usually within 2-3 years of symptom onset. Respiratory insufficiency is a common cause of morbidity, particularly in later stages of MND and respiratory complications are the leading cause of mortality in MND patients. Non Invasive Ventilation (NIV is the current standard therapy to manage respiratory insufficiency. Some MND patients however do not tolerate NIV due to a number of issues including mask interface problems and claustrophobia. In those that do tolerate NIV, eventually respiratory muscle weakness will progress to a point at which intermittent/overnight NIV is ineffective. The NeuRx RA/4 Diaphragm Pacing System was originally developed for patients with respiratory insufficiency and diaphragm paralysis secondary to stable high spinal cord injuries. The DiPALS study will assess the effect of diaphragm pacing (DP when used to treat patients with MND and respiratory insufficiency. Method/Design 108 patients will be recruited to the study at 5 sites in the UK. Patients will be randomised to either receive NIV (current standard care or receive DP in addition to NIV. Study participants will be required to complete outcome measures at 5 follow up time points (2, 3, 6, 9 and 12 months plus an additional surgery and 1 week post operative visit for those in the DP group. 12 patients (and their carers from the DP group will also be asked to complete 2 qualitative interviews. Discussion The primary objective of this trial will be to evaluate the effect of Diaphragm Pacing (DP on survival over the study duration in patients with MND with respiratory muscle weakness. The project is funded by the National Institute for Health Research, Health Technology Assessment (HTA Programme (project number 09/55/33 and the Motor Neurone Disease Association and the Henry Smith Charity. Trial Registration: Current controlled trials ISRCTN53817913. The

  4. Pace bowlers in cricket with history of lumbar stress fracture have increased risk of lower limb muscle strains, particularly calf strains

    Directory of Open Access Journals (Sweden)

    John Orchard

    2010-09-01

    Full Text Available John Orchard1, Patrick Farhart2, Alex Kountouris3, Trefor James3, Marc Portus31School of Public Health, University of Sydney, Australia; 2Punjab Kings XI team, Indian Premier League, India; 3Cricket Australia, Melbourne, AustraliaObjective: To assess whether a history of lumbar stress fracture in pace bowlers in cricket is a risk factor for lower limb muscle strains.Methods: This was a prospective cohort risk factor study, conducted using injury data from contracted first class pace bowlers in Australia during seasons 1998–1999 to 2008–2009 inclusive. There were 205 pace bowlers, 33 of whom suffered a lumbar stress fracture when playing first class cricket. Risk ratios ([RR] with 95% confidence intervals[CI] were calculated to compare the seasonal incidence of various injuries between bowlers with a prior history of lumbar stress fracture and those with no history of lumbar stress fracture.Results: Risk of calf strain was strongly associated with prior lumbar stress fracture injury history (RR = 4.1; 95% CI: 2.4–7.1. Risks of both hamstring strain (RR = 1.5; 95% CI: 1.03–2.1 and quadriceps strain (RR = 2.0; 95% CI: 1.1–3.5 were somewhat associated with history of lumbar stress fracture. Risk of groin strain was not associated with history of lumbar stress fracture (RR = 0.7; 95% CI: 0.4–1.1. Other injuries showed little association with prior lumbar stress fracture, although knee cartilage injuries were more likely in the non-stress fracture group.Conclusion: Bony hypertrophy associated with lumbar stress fracture healing may lead to subsequent lumbar nerve root impingement, making lower limb muscle strains more likely to occur. Confounders may be responsible for some of the findings. In particular, bowling speed is likely to be independently correlated with risk of lumbar stress fracture and risk of muscle strain. However, as the relationship between lumbar stress fracture history and calf strain was very strong, and that there is a

  5. Nanotechnology: a future tool to improve quality and safety in meat industry.

    Science.gov (United States)

    Singh, Pradeep Kumar; Jairath, Gauri; Ahlawat, Satyavir Singh

    2016-04-01

    Nanotechnology refers to the new aspect of science modifies its physical, chemical and biological properties leading to new applications or enhanced utility. Keeping the pace with other industries, the meat industry has adopted the new technology in a range of applications to improve the quality and safety of products. The potential applications include the improvement in the tastes, texture, flavor, production of low fat and salt products, enhanced nutrient absorption, improved packaging techniques and better pathogen detection system. However some safety issues need to be addressed before taking a ride on the technology at the full throttle. PMID:27413202

  6. OEE Evaluation of a Paced Assembly Line Through Different Calculation and Simulation Methods: A Case Study in the Pharmaceutical Environment

    OpenAIRE

    Filippo De Carlo; Maria Antonietta Arleo; Mario Tucci

    2014-01-01

    Modern production systems must guarantee high performance. Increasingly challenging international competition, budget reductions for the health sector and constant technological evolution are just three of the many aspects that drive pharmaceutical companies to continuously improve the productivity of their lines. The scientific literature has for many years been proposing calculation models for estimating the productivity of a machine. One of the most famous, and...

  7. Cardiac resynchronization therapy: Dire need for targeted left ventricular lead placement and optimal device programming

    Institute of Scientific and Technical Information of China (English)

    Sokratis; Pastromas; Antonis; S; Manolis

    2014-01-01

    Cardiac resynchronization therapy(CRT) effected via biventricular pacing has been established as prime therapy for heart failure patients of New York Heart Association functional class Ⅱ, Ⅲ and ambulatory Ⅳ, reduced left ventricular(LV) function, and a widened QRS complex. CRT has been shown to improve symptoms, LV function, hospitalization rates, and survival. In order to maximize the benefit from CRT and reduce the number of non-responders, consideration should be given to target the optimal site for LV lead implantation away from myocardial scar and close to the latest LV site activation; and also to appropriately program the device paying particular attention to optimal atrioventricular and interventricular intervals. We herein review current data related to both optimal LV lead placement and device programming and their effects on CRT clinical outcomes.

  8. Toward a semi-self-paced EEG brain computer interface: decoding initiation state from non-initiation state in dedicated time slots.

    Directory of Open Access Journals (Sweden)

    Lingling Yang

    Full Text Available Brain computer interfaces (BCIs offer a broad class of neurologically impaired individuals an alternative means to interact with the environment. Many BCIs are "synchronous" systems, in which the system sets the timing of the interaction and tries to infer what control command the subject is issuing at each prompting. In contrast, in "asynchronous" BCIs subjects pace the interaction and the system must determine when the subject's control command occurs. In this paper we propose a new idea for BCI which draws upon the strengths of both approaches. The subjects are externally paced and the BCI is able to determine when control commands are issued by decoding the subject's intention for initiating control in dedicated time slots. A single task with randomly interleaved trials was designed to test whether it can be used as stimulus for inducing initiation and non-initiation states when the sensory and motor requirements for the two types of trials are very nearly identical. Further, the essential problem on the discrimination between initiation state and non-initiation state was studied. We tested the ability of EEG spectral power to distinguish between these two states. Among the four standard EEG frequency bands, beta band power recorded over parietal-occipital cortices provided the best performance, achieving an average accuracy of 86% for the correct classification of initiation and non-initiation states. Moreover, delta band power recorded over parietal and motor areas yielded a good performance and thus could also be used as an alternative feature to discriminate these two mental states. The results demonstrate the viability of our proposed idea for a BCI design based on conventional EEG features. Our proposal offers the potential to mitigate the signal detection challenges of fully asynchronous BCIs, while providing greater flexibility to the subject than traditional synchronous BCIs.

  9. Prior low- or high-intensity exercise alters pacing strategy, energy system contribution and performance during a 4-km cycling time trial.

    Science.gov (United States)

    Correia-Oliveira, Carlos Rafaell; Santos, Ralmony Alcantara; Silva-Cavalcante, Marcos David; Bertuzzi, Romulo; Kiss, Maria Augusta Peduti Dal'Molin; Bishop, David John; Lima-Silva, Adriano Eduardo

    2014-01-01

    We analyzed the influence of prior exercise designed to reduce predominantly muscle glycogen in either type I or II fibers on pacing and performance during a 4-km cycling time trial (TT). After preliminary and familiarization trials, in a randomized, repeated-measures crossover design, ten amateur cyclists performed: 1) an exercise designed to reduce glycogen of type I muscle fibers, followed by a 4-km TT (EX-FIB I); 2) an exercise designed to reduce glycogen of type II muscle fibers, followed by a 4-km TT (EX-FIB II) and; 3) a 4-km TT, without the prior exercise (CONT). The muscle-glycogen-reducing exercise in both EX-FIB I and EX-FIB II was performed in the evening, ∼12 h before the 4-km TT. Performance time was increased and power output (PO) was reduced in EX-FIB I (432.8±8.3 s and 204.9±10.9 W) and EX-FIB II (428.7±6.7 s and 207.5±9.1 W) compared to CONT (420.8±6.4 s and 218.4±9.3 W; P0.05). The PO was lower in EX-FIB I than in CONT at the beginning and middle of the trial (P0.05). The integrated electromyography was unchanged between conditions (P>0.05). Performance may have been impaired in EX-FIB I due a more conservative pacing at the beginning and middle, which was associated with a reduced aerobic contribution. In turn, the PO profile adopted in EX-FIB II was also reduced throughout the trial, but the impairment in performance may be attributed to a reduced glycolytic contribution (i.e. reduced lactate accumulation). PMID:25330452

  10. Prior low- or high-intensity exercise alters pacing strategy, energy system contribution and performance during a 4-km cycling time trial.

    Directory of Open Access Journals (Sweden)

    Carlos Rafaell Correia-Oliveira

    Full Text Available We analyzed the influence of prior exercise designed to reduce predominantly muscle glycogen in either type I or II fibers on pacing and performance during a 4-km cycling time trial (TT. After preliminary and familiarization trials, in a randomized, repeated-measures crossover design, ten amateur cyclists performed: 1 an exercise designed to reduce glycogen of type I muscle fibers, followed by a 4-km TT (EX-FIB I; 2 an exercise designed to reduce glycogen of type II muscle fibers, followed by a 4-km TT (EX-FIB II and; 3 a 4-km TT, without the prior exercise (CONT. The muscle-glycogen-reducing exercise in both EX-FIB I and EX-FIB II was performed in the evening, ∼12 h before the 4-km TT. Performance time was increased and power output (PO was reduced in EX-FIB I (432.8±8.3 s and 204.9±10.9 W and EX-FIB II (428.7±6.7 s and 207.5±9.1 W compared to CONT (420.8±6.4 s and 218.4±9.3 W; P0.05. The PO was lower in EX-FIB I than in CONT at the beginning and middle of the trial (P0.05. The integrated electromyography was unchanged between conditions (P>0.05. Performance may have been impaired in EX-FIB I due a more conservative pacing at the beginning and middle, which was associated with a reduced aerobic contribution. In turn, the PO profile adopted in EX-FIB II was also reduced throughout the trial, but the impairment in performance may be attributed to a reduced glycolytic contribution (i.e. reduced lactate accumulation.

  11. Collaborative Improvement

    DEFF Research Database (Denmark)

    Kaltoft, Rasmus

    The thesis data have been collected in the EU-sponsored project: Collaborative Improvement Tool for the Extended Manufacturing Enterprise, CO-IMPROVE. In this project four universities (Denmark, Ireland, Italy, and The Netherlands), two software vendors (Greece and Sweden) and three companies (De...... learn how to improve operations in (hopefully) a win-win like manner through collaboration.......The thesis data have been collected in the EU-sponsored project: Collaborative Improvement Tool for the Extended Manufacturing Enterprise, CO-IMPROVE. In this project four universities (Denmark, Ireland, Italy, and The Netherlands), two software vendors (Greece and Sweden) and three companies...... (Denmark, Italy and The Netherlands) each with three to five suppliers were involved. The CO-IMPROVE project and the thesis is based on “action research” and “action learning”. The main aim of the whole project is through actual involvement and actions make the researchers, companies and selected suppliers...

  12. Computer assisted optimisation on non-pharmacological treatment of congestive heart failure and supraventricular arrhythmia

    OpenAIRE

    Reumann, Matthias

    2007-01-01

    Heart Failure is the most common cardiac disease worldwide; supraventricular arrhythmia the most common cardiac arrhythmia. The understanding of these diseases advances treatment options. Ablation therapy and atrial antitachycardial pacing are non-pharmacological options in the treatment of atrial fibrillation. Cardiac resynchronization therapy with biventricular pacing devices has been shown successful in patients with severe heart failure. However, an optimization or even individual therapy...

  13. 对静水皮划艇比赛速度结构和战术规律性探讨%The Study On The Strategy Disciplinarian And Pace Profile In Competitions On Flat 'Water Ca- noe

    Institute of Scientific and Technical Information of China (English)

    吕蓉; 肖青; 裘艺; 陈晓赜

    2012-01-01

    The specific sports features, the present form of pace profile, the action of relative strategy on the performance in competitions, the practical application of pace profile in canoe competitions for domestic and foreign area are analyzed on the basis of literature and recording research methods in this study. The purpose is get the conclusions for pace disciplinarian, the mode of pace profile and the features of energy metabolism in canoe competitions, as well as bring forward the emphases and directions of study on canoe competition strate- gy.%在文献资料法和录像分析法的基础上分析介绍了静水皮划艇项目的专项运动特征、速度结构的表现形式,相应的战术在大赛中的制胜作用、国内外在皮划艇比赛中速度结构的实践运用,目的是总结皮划艇比赛中的竞速规律、速度结构模式和能量代谢特点,提出皮艇战术研究的重点和方向。

  14. National healthcare information system in Croatian primary care: the foundation for improvement of quality and efficiency in patient care

    OpenAIRE

    Darko Gvozdanovi_; Miroslav Kon_ar; Vinko Kojund_i_; Hrvoje Jezid_i_

    2007-01-01

    In order to improve the quality of patient care, while at the same time keeping up with the pace of increased needs of the population for healthcare services that directly impacts on the cost of care delivery processes, the Republic of Croatia, under the leadership of the Ministry of Health and Social Welfare, has formed a strategy and campaign for national public healthcare system reform. The strategy is very comprehensive and addresses all niches of care delivery processes; it is founded on...

  15. 球囊漂浮电极导管床旁心脏临时起搏术40例临床分析%Clinical analysis of floating catheter in bedside temporary cardiac pacing in 40 patients

    Institute of Scientific and Technical Information of China (English)

    叶剑飞; 刘晓凯; 郑林; 茅焕豪; 郑伟峰; 张茗茗

    2012-01-01

    Objectives To observe the clinical effect of floating catheter in bedside temporary cardiac pacing. Methods Forty patients with severe bradyarrhythmia were included in this study and floating catheter for temporary cardiac pacing was propelled into right ventricle by Seldinger technique without fluoroscopy, under the guidance of bedside electrocardiography monitoring. The location of electrods were confirmed by QRS wave. The duration of placing floating catheter and the average time of pacing were recorded, and the complications of pacing were observed. Results Forty patients were successfully punctured, with an average duration of placing floating catheter of(9.1±2.1) min, pacing time of 1-15 days (median time of 5.5 days). Two cases were on loosen electrode, but no other complications were found. Conclusions Bedside floating electrode catheter can be used without fluoroscopy and replacement of critical patients in emergent pacing, with characters of easy performing, rapid pacing, definite effects and relative safety, and it is suitable for promotion in primary hospitals.%目的 观察漂浮电极导管床旁临时心脏起搏的临床应用效果.方法 对40例严重缓慢型心律失常患者在床旁体表心电图临护指导下,通过Seldinger穿刺技术,在无X线透视条件下将临时起搏漂浮电极导管送人右心室,通过体表心电图QRS波群确定电极位置.记录放置电极导管所花费的时间与平均起搏时间,观察临时起搏操作并发症.结果 40例患者穿刺均获成功,安置球囊漂浮电极导管平均操作时间(9.1±2.1) min,起搏时间1-15 d,中位时间5.5d.电极脱位2例,无其他并发症.结论 床旁漂浮电极导管可在没有X线设备下紧急起搏而不需搬动危重患者,具有操作简单、起搏迅速、疗效肯定及相对安全的特点,适合在基层医院推广应用.

  16. CANDU improvement

    International Nuclear Information System (INIS)

    The evolution of the CANDU family of nuclear power plants is based on a continuous product development approach. Proven equipment and system concepts from operating stations are standardized and used in new products. Due to the modular nature of the CANDU reactor concept, product features developed for CANDU 9 can easily be incorporated in other CANDU products such as CANDU 6. Design concepts are being developed for advanced CANDU 6 or larger advanced CANDU, depending on the number of fuel channels and the fuel cycle selected. This paper provides a description of the design improvements being incorporated in CANDU 9 and further design enhancements being studied for future incorporation in CANDU 6 or larger advanced CANDU meeting the requirements of future CANDU owners. The design enhancement objectives are: To improve operational simplicity by applying modern information technology; to improve safety in a cost effective way; to improve system and component reliability and to increase plant life; to improve economics and to reduce owners' risks during all phases of a project using up-front licensing, an improved engineering process and project tools during design, construction and operation; to continue to exploit the neutron economy of CANDU with the development of advanced fuels and fuel cycles. (author)

  17. Integrating the pace-of-life syndrome across species, sexes and individuals: covariation of life history and personality under pesticide exposure.

    Science.gov (United States)

    Debecker, Sara; Sanmartín-Villar, Iago; de Guinea-Luengo, Miguel; Cordero-Rivera, Adolfo; Stoks, Robby

    2016-05-01

    The pace-of-life syndrome (POLS) hypothesis integrates covariation of life-history traits along a fast-slow continuum and covariation of behavioural traits along a proactive-reactive personality continuum. Few studies have investigated these predicted life-history/personality associations among species and between sexes. Furthermore, whether and how contaminants interfere with POLS patterns remains unexplored. We tested for covariation patterns in life history and in behaviour, and for life-history/personality covariation among species, among individuals within species and between sexes. Moreover, we investigated whether pesticide exposure affects covariation between life history and behaviour and whether species and sexes with a faster POLS strategy have a higher sensitivity to pesticides. We reared larvae of four species of Ischnura damselflies in a common garden experiment with an insecticide treatment (chlorpyrifos absent/present) in the final instar. We measured four life-history traits (larval growth rate during the pesticide treatment, larval development time, adult mass and life span) and two behavioural traits (larval feeding activity and boldness, each before and after the pesticide treatment). At the individual level, life-history traits and behavioural traits aligned along a fast-slow and a proactive-reactive continuum, respectively. Species-specific differences in life history, with fast-lived species having a faster larval growth and development, a lower mass at emergence and a shorter life span, suggested that time constraints in the larval stage were predictably driving life-history evolution both in the larval stage and across metamorphosis in the adult stage. Across species, females were consistently more slow-lived than males, reflecting that a large body size and a long life span are generally more important for females. In contrast to the POLS hypothesis, there was only little evidence for the expected positive coupling between life

  18. 不同节奏下奥运会男篮比赛技术统计差异分析%An analysis of technical statistic differences between Olympic basketball games played at different paces

    Institute of Scientific and Technical Information of China (English)

    张学领

    2014-01-01

    通过对奥运会男篮比赛在不同节奏下获胜球队和失败球队的数据对比以及不同节奏下技术统计指标的差异分析,探索影响篮球比赛节奏的技术因素及影响比赛胜负的因素;通过中国队与对手的比较,寻找中国队在历届奥运会存在的问题,为今后的训练和比赛提供参考依据。研究结果显示:在较快节奏下胜队更能发挥出实力优势,表现出较高的绩效;在较慢的节奏中弱队能够减少与强队技术统计数据上的差距。2分投、抢断、2分中、失误决定着控球权次数,影响着比赛节奏的快慢。中国队在快节奏比赛中综合表现很差;一般节奏下2分球命中率较低,3分投篮出手机会较少,助攻较少,失误较多;在慢节奏下中国队才能正常发挥自己的水平,胜率较高。%By comparing the data of winning and losing teams in Olympic men’s basketball games played at different paces, and by analyzing technical statistic differences between the games played at different paces, the author probed into basketball game pace affecting technical factors and game outcome affecting factors; by comparing team China with its opponents, the author sought for problems which team China had in all previous Olympic Games, so as to provide a refer-ence criterion for training and competition henceforward. The author revealed the following findings: at a faster pace, the winning teams were more capable of exerting their strength advantage, showing higher performance; at a slower pace, the weak teams could reduce their differences form the strong teams in terms of technical statistic data; two-point shots, steals, two-point winners and turnovers determined the number of ball possessions, affected the pace of a game; in fast pace games, team China had very poor comprehensive performance; at an ordinary pace, team China had a low two-point win-ner rate, few three-point shooting opportunities, few assists

  19. Influence of High Right Ventricular Septal Pacing and Right Ventricular Apical Pacing on Cardiac Function%高位右室间隔部起搏与右室心尖部起搏对患者心功能的影响

    Institute of Scientific and Technical Information of China (English)

    贾国力; 邢程; 王海珠; 韩彩萍

    2015-01-01

    Objective:To explore the influence of high right ventricular septal(HRVS)pacing and right ventricular apical(RVA)pacing on patients’ cardiac function,left ventricular remodeling and ventricular synchrony.Method:126 patients who implanted VVI pacemaker because ofⅢdegree atrioventricular block(ⅢAVB)or sick sinus syndrome(SSS)in our hospital from January 2008 to December 2012 were selected as the research objects.Among them,there were 61 cases with RVA pacing and 65 cases with HRVS.The left ventricular ejection fraction(LVEF),left ventricular end-diastolic diameter(LVEDD), QRS wave group width and New York Heart Association(NYHA)functional classification of the two groups were observed and compared before operation and six months,1 year after operation.The number of hospitalizations for heart failure after operation was compared between the two groups.Result:Before treatment,the differences in the indexes of the two groups were not statistically significant(P>0.05).Six months and one year after surgery,the LVEF of the HRVS group was higher than that of the RVA group,the LVEDD and QRS wave width of the HRVS group were lower than those of the RVA group,the differences above were all statistically significant(P0.05),术后6个月及1年,HRVS组LVEF高于RVA组,LVEDD及QRS波宽度均低于RVA组,比较差异均有统计学意义(P<0.05);术后1年,HRVS组NYHA心功能Ⅲ/Ⅳ级及因心力衰竭住院患者数低于RVA组,比较差异均有统计学意义(P<0.05)。结论:HRVS起搏对心脏起搏治疗患者心功能的不利影响低于RVA起搏,是更理想的起搏部位。

  20. PACE-90 water and solute transport calculations for 0.01, 0.1, and 0. 5 mm/yr infiltration into Yucca Mountain

    International Nuclear Information System (INIS)

    Numerical results are presented for the Performance Assessment Calculational Exercise (PACE-90). One- and two-dimensional water and solute transport are presented for steady infiltration into Yucca Mountain. Evenly distributed infiltration rates of 0.01, 0.1, and 0.5 mm/yr were considered. The calculations of solute transport show that significant amounts of radionuclides can reach the water table over 100,000 yr at the 0.5 mm/yr rate. For time periods less than 10,000 yr or infiltrations less than 0.1 mm/yr very little solute reaches the water table. The numerical simulations clearly demonstrate that multi-dimensional effects can result in significant decreases in the travel time of solute through the modeled domain. Dual continuum effects are shown to be negligible for the low steady state fluxes considered. However, material heterogeneities may cause local amplification of the flux level in multi-dimensional flows. These higher flux levels may then require modeling of a dual continuum porous medium