Sample records for extremely rapid pace

  1. Optimizing local capture of atrial fibrillation by rapid pacing: study of the influence of tissue dynamics.

    PubMed

    Uldry, Laurent; Virag, Nathalie; Jacquemet, Vincent; Vesin, Jean-Marc; Kappenberger, Lukas

    2010-12-01

    While successful termination by pacing of organized atrial tachycardias has been observed in patients, rapid pacing of AF can induce a local capture of the atrial tissue but in general no termination. The purpose of this study was to perform a systematic evaluation of the ability to capture AF by rapid pacing in a biophysical model of the atria with different dynamics in terms of conduction velocity (CV) and action potential duration (APD). Rapid pacing was applied during 30 s at five locations on the atria, for pacing cycle lengths in the range 60-110% of the mean AF cycle length (AFCL(mean)). Local AF capture could be achieved using rapid pacing at pacing sites located distal to major anatomical obstacles. Optimal pacing cycle lengths were found in the range 74-80% AFCL(mean) (capture window width: 14.6 ± 3% AFCL(mean)). An increase/decrease in CV or APD led to a significant shrinking/stretching of the capture window. Capture did not depend on AFCL, but did depend on the atrial substrate as characterized by an estimate of its wavelength, a better capture being achieved at shorter wavelengths. This model-based study suggests that a proper selection of the pacing site and cycle length can influence local capture results and that atrial tissue properties (CV and APD) are determinants of the response to rapid pacing.

  2. Angiotensin-converting enzyme and matrix metalloproteinase inhibition with developing heart failure: comparative effects on left ventricular function and geometry

    NASA Technical Reports Server (NTRS)

    McElmurray, J. H. 3rd; Mukherjee, R.; New, R. B.; Sampson, A. C.; King, M. K.; Hendrick, J. W.; Goldberg, A.; Peterson, T. J.; Hallak, H.; Zile, M. R.; hide

    1999-01-01

    The progression of congestive heart failure (CHF) is left ventricular (LV) myocardial remodeling. The matrix metalloproteinases (MMPs) contribute to tissue remodeling and therefore MMP inhibition may serve as a useful therapeutic target in CHF. Angiotensin converting enzyme (ACE) inhibition favorably affects LV myocardial remodeling in CHF. This study examined the effects of specific MMP inhibition, ACE inhibition, and combined treatment on LV systolic and diastolic function in a model of CHF. Pigs were randomly assigned to five groups: 1) rapid atrial pacing (240 beats/min) for 3 weeks (n = 8); 2) ACE inhibition (fosinopril, 2.5 mg/kg b.i.d. orally) and rapid pacing (n = 8); 3) MMP inhibition (PD166793 2 mg/kg/day p.o.) and rapid pacing (n = 8); 4) combined ACE and MMP inhibition (2.5 mg/kg b.i.d. and 2 mg/kg/day, respectively) and rapid pacing (n = 8); and 5) controls (n = 9). LV peak wall stress increased by 2-fold with rapid pacing and was reduced in all treatment groups. LV fractional shortening fell by nearly 2-fold with rapid pacing and increased in all treatment groups. The circumferential fiber shortening-systolic stress relation was reduced with rapid pacing and increased in the ACE inhibition and combination groups. LV myocardial stiffness constant was unchanged in the rapid pacing group, increased nearly 2-fold in the MMP inhibition group, and was normalized in the ACE inhibition and combination treatment groups. Increased MMP activation contributes to the LV dilation and increased wall stress with pacing CHF and a contributory downstream mechanism of ACE inhibition is an effect on MMP activity.

  3. Effect of short-term rapid ventricular pacing followed by pacing interruption on arterial blood pressure in healthy pigs and pigs with tachycardiomyopathy.

    PubMed

    Skrzypczak, P; Zyśko, D; Pasławska, U; Noszczyk-Nowak, A; Janiszewski, A; Gajek, J; Nicpoń, J; Kiczak, L; Bania, J; Zacharski, M; Tomaszek, A; Jankowska, E A; Ponikowski, P; Witkiewicz, W

    2014-01-01

    Ventricular tachycardia may lead to haemodynamic deterioration and, in the case of long term persistence, is associated with the development of tachycardiomyopathy. The effect of ventricular tachycardia on haemodynamics in individuals with tachycardiomyopathy, but being in sinus rhythm has not been studied. Rapid ventricular pacing is a model of ventricular tachycardia. The aim of this study was to determine the effect of rapid ventricular pacing on blood pressure in healthy animals and those with tachycardiomyopathy. A total of 66 animals were studied: 32 in the control group and 34 in the study group. The results of two groups of examinations were compared: the first performed in healthy animals (133 examinations) and the second performed in animals paced for at least one month (77 examinations). Blood pressure measurements were taken during chronic pacing--20 min after onset of general anaesthesia, in baseline conditions (20 min after pacing cessation or 20 min after onset of general anaesthesia in healthy animals) and immediately after short-term rapid pacing. In baseline conditions significantly higher systolic and diastolic blood pressure was found in healthy animals than in those with tachycardiomyopathy. During an event of rapid ventricular pacing, a significant decrease in systolic and diastolic blood pressure was found in both groups of animals. In the group of chronically paced animals the blood pressure was lower just after restarting ventricular pacing than during chronic pacing. Cardiovascular adaptation to ventricular tachycardia develops with the length of its duration. Relapse of ventricular tachycardia leads to a blood pressure decrease more pronounced than during chronic ventricular pacing.

  4. Atrial Fibrillation Pacing Decreases Intravascular Shear Stress in a New Zealand White Rabbit Model: Implications in Endothelial Function

    PubMed Central

    Jen, Nelson; Yu, Fei; Lee, Juhyun; Wasmund, Steve; Dai, Xiaohu; Chen, Christina; Chawareeyawong, Pai; Yang, Yongmo; Li, Rongsong; Hamdan, Mohamed H.; Hsiai, Tzung

    2012-01-01

    Atrial fibrillation (AF) is characterized by multiple rapid and irregular atrial depolarization leading to rapid ventricular responses exceeding 100 beats per minute (bpm). We hypothesized that rapid and irregular pacing reduced intravascular shear stress (ISS) with implication to modulating endothelial responses. To simulate AF, we paced the left atrial appendage of New Zealand White (NZW) rabbits (n=4) at rapid and irregular intervals. Surface electrical cardiograms (ECG) were recorded for atrial and ventricular rhythm, and intravascular convective heat transfer was measured by micro thermal sensors, from which ISS was inferred. Rapid and irregular pacing decreased arterial systolic and diastolic pressures (baseline: 99/75 mmHg; rapid regular pacing: 92/73; rapid irregular pacing: 90/68; P < 0.001, n=4), temporal gradients (∂τ/∂t from 1275 ± 80 to 1056 ± 180 dyne/cm2·s), and reduced ISS (from baseline at 32.0 ± 2.4 to 22.7 ± 3.5 dyne/cm2). Computational fluid dynamics (CFD) code demonstrated that experimentally inferred ISS provided a close approximation to the computed wall shear stress (WSS) at a given catheter to vessel diameter ratio, shear stress range, and catheter position. In an in vitro flow system in which time-averaged shear stress was maintained at τavg=23 ±4 dyn·cm−2·s−1, we further demonstrated that rapid pulse rates at 150 bpm down-regulated endothelial nitric oxide (NO), promoted superoxide (O2·−) production, and increased monocyte binding to endothelial cells. These findings suggest that rapid pacing reduces ISS and ∂τ/∂t, and rapid pulse rates modulate endothelial responses. PMID:22983703

  5. Introduction

    NASA Astrophysics Data System (ADS)

    Bouma, Brett E.

    1998-09-01

    The pace of technological advancement of Optical Coherence Tomography (OCT) over the last several years has been extremely rapid. The field has progressed from one-dimensional low-coherence ranging to full three-dimensional imaging with individual two-dimensional images aquired at near video rate in a span of less than eight years. Imaging applications have included polymers and advanced composites, Ophthalmology, Developmental Biology, Gastroenterology, Urology, Cardiology, Neurology, and Gynecology. These preliminary studies indicate the great potential for OCT to make a significant impact, especially in clinical medicine.

  6. Multi-brain fusion and applications to intelligence analysis

    NASA Astrophysics Data System (ADS)

    Stoica, A.; Matran-Fernandez, A.; Andreou, D.; Poli, R.; Cinel, C.; Iwashita, Y.; Padgett, C.

    2013-05-01

    In a rapid serial visual presentation (RSVP) images are shown at an extremely rapid pace. Yet, the images can still be parsed by the visual system to some extent. In fact, the detection of specific targets in a stream of pictures triggers a characteristic electroencephalography (EEG) response that can be recognized by a brain-computer interface (BCI) and exploited for automatic target detection. Research funded by DARPA's Neurotechnology for Intelligence Analysts program has achieved speed-ups in sifting through satellite images when adopting this approach. This paper extends the use of BCI technology from individual analysts to collaborative BCIs. We show that the integration of information in EEGs collected from multiple operators results in performance improvements compared to the single-operator case.

  7. Influence of atrial substrate on local capture induced by rapid pacing of atrial fibrillation.

    PubMed

    Rusu, Alexandru; Jacquemet, Vincent; Vesin, Jean-Marc; Virag, Nathalie

    2014-05-01

    Preliminary studies showed that the septum area was the only location allowing local capture of both the atria during rapid pacing of atrial fibrillation (AF) from a single site. The present model-based study investigated the influence of atrial substrate on the ability to capture AF when pacing the septum. Three biophysical models of AF with an identical anatomy from human atria but with different AF substrates were used: (i) AF based on multiple wavelets, (ii) AF based on heterogeneities in vagal activation, (iii) AF based on heterogeneities in repolarization. A fourth anatomical model without Bachmann's bundle (BB) was also implemented. Rapid pacing was applied from the septum at pacing cycle lengths in the range of 50-100% of AF cycle length. Local capture was automatically assessed with 24 pairs of electrodes evenly distributed on the atrial surface. The results were averaged over 16 AF simulations. In the homogeneous substrate, AF capture could reach 80% of the atrial surface. Heterogeneities degraded the ability to capture during AF. In the vagal substrate, the capture tended to be more regular and the degradation of the capture was not directly related to the spatial extent of the heterogeneities. In the third substrate, heterogeneities induced wave anchorings and wavebreaks even in areas close to the pacing site, with a more dramatic effect on AF capture. Finally, BB did not significantly affect the ability to capture. Atrial fibrillation substrate had a significant effect on rapid pacing outcomes. The response to therapeutic pacing may therefore be specific to each patient.

  8. Catheter Ablation of Focal Atrial Tachycardia Using Remote Magnetic Navigation.

    PubMed

    Webster, Mark; Pasupati, Sanjeevan; Lever, Nigel; Stiles, Martin

    2018-05-01

    This first-in-human study evaluated the safety and technical feasibility of the Tempo temporary cardiac pacing lead (BioTrace Medical), which includes a novel fixation mechanism and soft tip. Complications of temporary pacing leads include dislodgment, arrhythmias, and ventricular perforation. Temporary pacing applications have increased with transcatheter aortic valve replacement (TAVR) growth, for rapid pacing during balloon valvuloplasty (BAV) and valve deployment, and for periprocedural bradyarrhythmia support. Eligible patients required temporary pacing for TAVR, BAV, or electrophysiology (EP) procedures. Transthoracic echocardiograms were obtained at baseline and 24 hours after lead removal. Safety was defined as freedom from pericardial effusion requiring intervention or evidence of tamponade. Technical feasibility involved successful intracardiac delivery and pace capture. Additional evaluations included pacing threshold (PCT), rapid pacing, dislodgment, or sustained ventricular arrhythmias. Follow-up was to 30 days. Twenty-five patients (60% female; mean age, 64 ± 19 years) underwent 13 TAVRs (7 Sapien 3 valves [Edwards Lifesciences], 4 CoreValves [Medtronic], and 2 Lotus valves [Boston Scientific]), 11 EP procedures, and 1 BAV at two New Zealand centers from January 2016 to June 2016. Safety was met in all patients, with no device-related adverse events. Technical feasibility was achieved in 23 cases (92%); 2 patients had unsuitable anatomy. No patient had lead dislodgment or sustained ventricular arrhythmias, and the final procedural PCT was 0.7 ± 0.5 mA. Rapid pacing was successful in all cases. Five patients had successful postprocedural use up to 5 days. This first-in-human study demonstrates the safety and technical feasibility of the Tempo lead, providing stable periprocedural temporary pacing support.

  9. Statistical innovations in diagnostic device evaluation.

    PubMed

    Yu, Tinghui; Li, Qin; Gray, Gerry; Yue, Lilly Q

    2016-01-01

    Due to rapid technological development, innovations in diagnostic devices are proceeding at an extremely fast pace. Accordingly, the needs for adopting innovative statistical methods have emerged in the evaluation of diagnostic devices. Statisticians in the Center for Devices and Radiological Health at the Food and Drug Administration have provided leadership in implementing statistical innovations. The innovations discussed in this article include: the adoption of bootstrap and Jackknife methods, the implementation of appropriate multiple reader multiple case study design, the application of robustness analyses for missing data, and the development of study designs and data analyses for companion diagnostics.

  10. Zebrafish Melanoma.

    PubMed

    Kaufman, Charles K

    2016-01-01

    Melanoma skin cancer is a potentially deadly disease in humans and has remained extremely difficult to treat once it has metastasized. In just the last 10 years, a number of models of melanoma have been developed in the zebrafish that are biologically faithful to the human disease and have already yielded important insights into the fundamental biology of melanoma and offered new potential avenues for treatment. With the diversity and breadth of the molecular genetic tools available in the zebrafish, these melanoma models will continue to be refined and expanded upon to keep pace with the rapidly evolving field of melanoma biology.

  11. Effect of 1. 5 tesla nuclear magnetic resonance imaging scanner on implanted permanent pacemakers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hayes, D.L.; Holmes, D.R. Jr.; Gray, J.E.

    1987-10-01

    Patients with a permanent pacemaker are currently restricted from diagnostic nuclear magnetic resonance (NMR) imaging because of potential adverse effects on the pacemaker by the magnet. Previous work has shown that NMR imaging will result in asynchronous pacing of the pulse generator within a given distance of the magnet. The radiofrequency signal generated by the system may also result in rapid cardiac pacing, which may have deleterious effects. This study utilized a 1.5 tesla unit in an in vivo laboratory animal to evaluate the unit's effects on eight different pulse generators from two manufacturers. All pacemakers functioned in an asynchronousmore » mode when placed within a certain distance of the magnet. In addition, transient reed switch inhibition was observed. Seven of the eight pulse generators paced rapidly when exposed to the radiofrequency signal and there was a dramatic decrease in arterial blood pressure. Whether effective rapid cardiac pacing would occur could not be predicted before exposure to the magnetic resonance unit. Nuclear magnetic resonance imaging with high magnetic fields in patients with a pacemaker should continue to be avoided until the mechanism of the rapid cardiac pacing can be further delineated and either predicted or prevented.« less

  12. Kinetics of atrial repolarization alternans in a free-behaving ovine model.

    PubMed

    Jousset, Florian; Tenkorang, Joanna; Vesin, Jean-Marc; Pascale, Patrizio; Ruchat, Patrick; Rollin, Anne Garderes; Fromer, Martin; Narayan, Sanjiv M; Pruvot, Etienne

    2012-09-01

    Kinetics of Atrial Repolarization Alternans. Repolarization alternans (Re-ALT), a beat-to-beat alternation in action potential repolarization, promotes dispersion of repolarization, wavebreaks, and reentry. Recently, Re-ALT has been shown to play an important role in the transition from rapid pacing to atrial fibrillation (AF) in humans. The detailed kinetics of atrial Re-ALT, however, has not been reported so far. We developed a chronic free-behaving ovine pacing model to study the kinetics of atrial Re-ALT as a function of pacing rate. Thirteen sheep were chronically implanted with 2 pacemakers for the recording of broadband right atrial unipolar electrograms and delivery of rapid pacing protocols. Beat-to-beat differences in the atrial T-wave apex amplitude as a measure of Re-ALT and activation time were analyzed at incremental pacing rates until the effective refractory period (ERP) defined as stable 2:1 capture. Atrial Re-ALT appeared intermittently but without periodicity, and increased in amplitude as a function of pacing rate until ERP. Intermittent 2:1 atrial capture was observed at pacing cycle lengths 40 ms above ERP, and increased in duration as a function of pacing rate. Episodes of rapid pacing-induced AF were rare, and were preceded by Re-ALT or complex oscillations of atrial repolarization, but without intermittent capture. We show in vivo that atrial Re-ALT developed and increased in magnitude with rate until stable 2:1 capture. In rare instances where capture failure did not occur, Re-ALT and complex oscillations of repolarization surged and preceded AF initiation. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1003-1012, September 2012). © 2012 Wiley Periodicals, Inc.

  13. Constant DI pacing suppresses cardiac alternans formation in numerical cable models

    NASA Astrophysics Data System (ADS)

    Zlochiver, S.; Johnson, C.; Tolkacheva, E. G.

    2017-09-01

    Cardiac repolarization alternans describe the sequential alternation of the action potential duration (APD) and can develop during rapid pacing. In the ventricles, such alternans may rapidly turn into life risking arrhythmias under conditions of spatial heterogeneity. Thus, suppression of alternans by artificial pacing protocols, or alternans control, has been the subject of numerous theoretical, numerical, and experimental studies. Yet, previous attempts that were inspired by chaos control theories were successful only for a short spatial extent (<2 cm) from the pacing electrode. Previously, we demonstrated in a single cell model that pacing with a constant diastolic interval (DI) can suppress the formation of alternans at high rates of activation. We attributed this effect to the elimination of feedback between the pacing cycle length and the last APD, effectively preventing restitution-dependent alternans from developing. Here, we extend this idea into cable models to study the extent by which constant DI pacing can control alternans during wave propagation conditions. Constant DI pacing was applied to ventricular cable models of up to 5 cm, using human kinetics. Our results show that constant DI pacing significantly shifts the onset of both cardiac alternans and conduction blocks to higher pacing rates in comparison to pacing with constant cycle length. We also demonstrate that constant DI pacing reduces the propensity of spatially discordant alternans, a precursor of wavebreaks. We finally found that the protective effect of constant DI pacing is stronger for increased electrotonic coupling along the fiber in the sense that the onset of alternans is further shifted to higher activation rates. Overall, these results support the potential clinical applicability of such type of pacing in improving protocols of implanted pacemakers, in order to reduce the risk of life-threatening arrhythmias. Future research should be conducted in order to experimentally validate these promising results.

  14. Chronic exposure to cocaine binging predisposes to an accelerated course of dilated cardiomyopathy in conscious dogs following rapid ventricular pacing.

    PubMed

    Parikh, Pratik; Nikolaidis, Lazaros A; Stolarski, Carol; Shen, You-Tang; Shannon, Richard P

    2005-12-01

    Despite extensive study, the extent to which cocaine use predisposes to cardiac injury remains unknown. We hypothesized that chronic cocaine binging would increase susceptibility to a subsequent cardiac insult, even in the absence of demonstrable effects on baseline hemodynamics. We studied progression of dilated cardiomyopathy (DCM) induced by rapid ventricular pacing (240 beats per minute) in five conscious, chronically instrumented dogs, after exposure to repetitive cocaine binging (COC) in the form of four consecutive 1 mg/kg i.v. boluses daily for 8 days, to simulate human cocaine abuse. We compared the results with nine control dogs (CON) undergoing the exact pacing protocol, without prior cocaine exposure. Baseline hemodynamics were not significantly altered by chronic cocaine exposure. Following 2 weeks of pacing, COC dogs exhibited accelerated progression to DCM, depressed plasma nitric oxide levels (CON, 17 +/- 2 microM; COC, 10 +/- 2 microM, p < 0.05), and a significantly greater increase in plasma epinephrine (CON, 33 +/- 6 pg/ml; COC, 104 +/- 24 pg/ml). After only 2 weeks of pacing, COC dogs demonstrated progressive DCM of a magnitude comparable with end-stage pacing-induced DCM. Chronic cocaine binging increases susceptibility to a subsequent myocardial insult and accelerates progression of DCM in conscious dogs following rapid pacing. These data suggest that although chronic cocaine use alone may not affect myocardial function, it predisposes to greater susceptibility to a superimposed insult.

  15. Higher Education in India: Growth, Concerns and Change Agenda

    ERIC Educational Resources Information Center

    Agarwal, Pawan

    2007-01-01

    Higher education in India has grown large since the country's independence in 1947. Starting from a small base, the pace of growth was initially rapid. Initially, the pace of growth was rapid. Enrollments grew by 13 to 14 percent per annum during the 1950s and 1960s. Over the past few decades, the growth rate has declined noticeably. Since then it…

  16. The promise and challenge of high-throughput sequencing of the antibody repertoire

    PubMed Central

    Georgiou, George; Ippolito, Gregory C; Beausang, John; Busse, Christian E; Wardemann, Hedda; Quake, Stephen R

    2014-01-01

    Efforts to determine the antibody repertoire encoded by B cells in the blood or lymphoid organs using high-throughput DNA sequencing technologies have been advancing at an extremely rapid pace and are transforming our understanding of humoral immune responses. Information gained from high-throughput DNA sequencing of immunoglobulin genes (Ig-seq) can be applied to detect B-cell malignancies with high sensitivity, to discover antibodies specific for antigens of interest, to guide vaccine development and to understand autoimmunity. Rapid progress in the development of experimental protocols and informatics analysis tools is helping to reduce sequencing artifacts, to achieve more precise quantification of clonal diversity and to extract the most pertinent biological information. That said, broader application of Ig-seq, especially in clinical settings, will require the development of a standardized experimental design framework that will enable the sharing and meta-analysis of sequencing data generated by different laboratories. PMID:24441474

  17. Rate-dependent Loss of Capture during Ventricular Pacing.

    PubMed

    Wang, Jingfeng; Chen, Haiyan; Su, Yangang; Ge, Junbo

    2015-01-01

    A 63-year-old patient who had undergone atrial septal defect surgical repair received implantation of a single chamber VVI pacemaker for long RR intervals during atrial fibrillation. One week later, an intermittent loss of capture and sensing failure was detected at a pacing rate of 70 beats/min. However, a successful capture was observed during rapid pacing. Consequently, the pacing rate was temporarily adjusted to 90 beats/min. At the 3-month follow-up, the pacemaker was shown to be functioning properly independent of the pacing rate. An echocardiogram showed that the increased pacing rates were accompanied by a reduction in the right ventricular outflow tract dimension. The pacemaker was then permanently programmed at a lower rate of 60 beats/min.

  18. Prevention of Atrial Fibrillation by Using Sarcoplasmic Reticulum Calcium ATPase Pump Overexpression in a Rabbit Model of Rapid Atrial Pacing.

    PubMed

    Wang, Hong Li; Zhou, Xian Hui; Li, Zhi Qiang; Fan, Ping; Zhou, Qi Na; Li, Yao Dong; Hou, Yue Mei; Tang, Bao Peng

    2017-08-16

    BACKGROUND Recent research suggests that abnormal Ca2+ handling plays a role in the occurrence and maintenance of atrial fibrillation (AF). Therefore, Ca2+ release and ingestion depend on properties of the ryanodine receptor (RyR) and sarcoplasmic reticulum Ca2+ATPase2a (SERCA2a). This study aimed to detect whether SERCA2a gene overexpression has a preventive effect on atrial fibrillation caused by rapid pacing right atrium. MATERIAL AND METHODS Forty-eight New Zealand white rabbits were randomly divided into a control group, AF group, AAV9/GFP group, and AAV9/SERCA2a group. The right atrium was rapidly paced at 600 beats/min for 30 days after an intraperitoneal injection of an adeno-associated virus expressing the SERCA2a gene and GFP. The AF induction rate and the effective refraction period (ERP) were measured after 0, 4, 8, 12, and 24 h of pacing. Western blot analysis was used to test for the expression of SERCA2a. Changes in atrial tissue structure were observed by H&E staining and electron microscopy. RESULTS The AF induction rate was higher in the AF groups than in the AAV9/SERCA2a group at different time points of pacing. After 12 h of pacing, ERP was significantly prolonged in the AAV9/SERCA2a group compared to the AF and AAV9/GFP groups (p<0.05). SERCA2a protein expression was significantly lower in the AF and AAV9/GFP groups compared to the control group (p<0.05), while expression was significantly higher in the AAV9/SERCA2a group than in the AF and AAV9/GFP groups (p<0.05). The myocardial structure of the AAV9/SERCA2a group was significantly improved compared with the AF group, indicating that SERCA2a overexpression relieved the structural remodeling of atrial fibrillation. CONCLUSIONS SERCA2a overexpression is capable of suppressing ERP shortening and AF induced by rapid pacing atrium. SERCA2a gene therapy is expected to be a new anti-atrial fibrillation strategy.

  19. Breakthrough: X-ray Laser Captures Atoms and Molecules in Action

    ScienceCinema

    Bergmann, Uwe

    2018-02-13

    The Linac Coherent Light Source at SLAC is the world's most powerful X-ray laser. Just two years after turning on in 2009, breakthrough science is emerging from the LCLS at a rapid pace. A recent experiment used the X-rays to create and probe a 2-million-degree piece of matter in a controlled way for the first time-a significant leap toward understanding the extreme conditions found in the hearts of stars and giant planets, and a finding which could further guide research into nuclear fusion, the mechanism that powers the sun. Upcoming experiments will investigate the fundamental, atomic-scale processes behind such phenomena as superconductivity and magnetism, as well as peering into the molecular workings of photosynthesis in plants.

  20. Familial resemblance and shared latent familial variance in recurrent fall risk in older women

    PubMed Central

    Cauley, Jane A.; Roth, Stephen M.; Kammerer, Candace; Stone, Katie; Hillier, Teresa A.; Ensrud, Kristine E.; Hochberg, Marc; Nevitt, Michael C.; Zmuda, Joseph M.

    2010-01-01

    Background: A possible familial component to fracture risk may be mediated through a genetic liability to fall recurrently. Methods: Our analysis sample included 186 female sibling-ships (n = 401) of mean age 71.9 yr (SD = 5.0). Using variance component models, we estimated residual upper-limit heritabilities in fall-risk mobility phenotypes (e.g., chair-stand time, rapid step-ups, and usual-paced walking speed) and in recurrent falls. We also estimated familial and environmental (unmeasured) correlations between pairs of fall-risk mobility phenotypes. All models were adjusted for age, height, body mass index, and medical and environmental factors. Results: Residual upper-limit heritabilities were all moderate (P < 0.05), ranging from 0.27 for usual-paced walking speed to 0.58 for recurrent falls. A strong familial correlation between usual-paced walking speed and rapid step-ups of 0.65 (P < 0.01) was identified. Familial correlations between usual-paced walking speed and chair-stand time (−0.02) and between chair-stand time and rapid step-ups (−0.27) were both nonsignificant (P > 0.05). Environmental correlations ranged from 0.35 to 0.58 (absolute values), P < 0.05 for all. Conclusions: There exists moderate familial resemblance in fall-risk mobility phenotypes and recurrent falls among older female siblings, which we expect is primarily genetic given that adult siblings live separate lives. All fall-risk mobility phenotypes may be coinfluenced at least to a small degree by shared latent familial or environmental factors; however, up to approximately one-half of the covariation between usual-paced walking speed and rapid step-ups may be due to a common set of genes. PMID:20167680

  1. Linagliptin prevents atrial electrical and structural remodeling in a canine model of atrial fibrillation.

    PubMed

    Igarashi, Tazuru; Niwano, Shinichi; Niwano, Hiroe; Yoshizawa, Tomoharu; Nakamura, Hironori; Fukaya, Hidehira; Fujiishi, Tamami; Ishizue, Naruya; Satoh, Akira; Kishihara, Jun; Murakami, Masami; Ako, Junya

    2018-05-02

    Dipeptidyl peptidase 4 (DPP-4) inhibitors have recently been reported to exhibit additional cardioprotective effects; however, their effect in atrial remodeling, such as in atrial fibrillation (AF), remains unclear. In this study, the effect of linagliptin on atrial electrical and structural remodeling was evaluated in a canine AF model. Sixteen beagle dogs with 3-week atrial rapid stimulation were divided into the linagliptin group (9 mg/kg/day, n = 8) and pacing control group (n = 8). Three additional dogs without rapid pacing were assigned into non-pacing group, which was used as sham in this study. In the dogs with rapid pacing, the atrial effective refractory period (AERP), conduction velocity (CV), and AF inducibility were evaluated and blood was sampled every week. After the entire protocol, atrial tissue was sampled for histological examinations using HE, Azan, and dihydroethidium (DHE) staining to evaluate any tissue damage or oxidative stress. The pacing control group exhibited a gradual AERP shortening and CV decrease along the time course as previously reported. In the linagliptin group, the AERP shortening was not affected, but the CV decrease was suppressed in comparison to the control group (p < 0.05). The AF inducibility was increased in the control group and suppressed in the linagliptin group (p < 0.05). The control group exhibited tissue fibrosis, the degree of which was suppressed in the linagliptin group. DHE staining exhibited suppression of the reactive oxygen species expression in the linagliptin group in comparison to the pacing control group. Linagliptin, a DPP-4-inhibitor, suppressed the AF inducibility, CV decrease, and overexpression of oxidative stress in the canine AF model. Such suppressive effects of linagliptin on AF in the canine model may possibly be related to the anti-oxidative effect.

  2. Breakthrough: X-ray Laser Captures Atoms and Molecules in Action

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bergmann, Uwe

    2012-04-26

    The Linac Coherent Light Source at SLAC is the world's most powerful X-ray laser. Just two years after turning on in 2009, breakthrough science is emerging from the LCLS at a rapid pace. A recent experiment used the X-rays to create and probe a 2-million-degree piece of matter in a controlled way for the first time-a significant leap toward understanding the extreme conditions found in the hearts of stars and giant planets, and a finding which could further guide research into nuclear fusion, the mechanism that powers the sun. Upcoming experiments will investigate the fundamental, atomic-scale processes behind such phenomenamore » as superconductivity and magnetism, as well as peering into the molecular workings of photosynthesis in plants.« less

  3. Early Sensitivity to Discourse-Level Anomalies: Evidence from Self-Paced Reading

    ERIC Educational Resources Information Center

    Stewart, Andrew J.; Kidd, Evan; Haigh, Matthew

    2009-01-01

    Two word-by-word, self-paced reading experiments investigated the speed with which readers were sensitive to discourse-level anomalies. An account arguing for delayed sensitivity (Guzman & Klin, 2000) was contrasted with one allowing for rapid sensitivity (Myers & O'Brien, 1998). Anomalies related to spatial information (Experiment 1) and…

  4. Even between-lap pacing despite high within-lap variation during mountain biking.

    PubMed

    Martin, Louise; Lambeth-Mansell, Anneliese; Beretta-Azevedo, Liane; Holmes, Lucy A; Wright, Rachel; St Clair Gibson, Alan

    2012-09-01

    Given the paucity of research on pacing strategies during competitive events, this study examined changes in dynamic high-resolution performance parameters to analyze pacing profiles during a multiple-lap mountain-bike race over variable terrain. A global-positioning-system (GPS) unit (Garmin, Edge 305, USA) recorded velocity (m/s), distance (m), elevation (m), and heart rate at 1 Hz from 6 mountain-bike riders (mean±SD age=27.2±5.0 y, stature=176.8±8.1 cm, mass=76.3±11.7 kg, VO2max=55.1±6.0 mL·kg(-1)·min1) competing in a multilap race. Lap-by-lap (interlap) pacing was analyzed using a 1-way ANOVA for mean time and mean velocity. Velocity data were averaged every 100 m and plotted against race distance and elevation to observe the presence of intralap variation. There was no significant difference in lap times (P=.99) or lap velocity (P=.65) across the 5 laps. Within each lap, a high degree of oscillation in velocity was observed, which broadly reflected changes in terrain, but high-resolution data demonstrated additional nonmonotonic variation not related to terrain. Participants adopted an even pace strategy across the 5 laps despite rapid adjustments in velocity during each lap. While topographical and technical variations of the course accounted for some of the variability in velocity, the additional rapid adjustments in velocity may be associated with dynamic regulation of self-paced exercise.

  5. Atrial overexpression of angiotensin-converting enzyme 2 improves the canine rapid atrial pacing-induced structural and electrical remodeling. Fan, ACE2 improves atrial substrate remodeling.

    PubMed

    Fan, Jinqi; Zou, Lili; Cui, Kun; Woo, Kamsang; Du, Huaan; Chen, Shaojie; Ling, Zhiyu; Zhang, Quanjun; Zhang, Bo; Lan, Xianbin; Su, Li; Zrenner, Bernhard; Yin, Yuehui

    2015-01-01

    The purpose of this study was to investigate whether atrial overexpression of angiotensin-converting enzyme 2 (ACE2) by homogeneous transmural atrial gene transfer can reverse atrial remodeling and its mechanisms in a canine atrial-pacing model. Twenty-eight mongrel dogs were randomly divided into four groups: Sham-operated, AF-control, gene therapy with adenovirus-enhanced green fluorescent protein (Ad-EGFP) and gene therapy with Ad-ACE2 (Ad-ACE2) (n = 7 per subgroup). AF was induced in all dogs except the Sham-operated group by rapid atrial pacing at 450 beats/min for 2 weeks. Ad-EGFP and Ad-ACE2 group then received epicardial gene painting. Three weeks after gene transfer, all animals except the Sham group underwent rapid atrial pacing for another 3 weeks and then invasive electrophysiological, histological and molecular studies. The Ad-ACE2 group showed an increased ACE2 and Angiotensin-(1-7) expression, and decreased Angiotensin II expression in comparison with Ad-EGFP and AF-control group. ACE2 overexpression attenuated rapid atrial pacing-induced increase in activated extracellular signal-regulated kinases and mitogen-activated protein kinases (MAPKs) levels, and decrease in MAPK phosphatase 1(MKP-1) level, resulting in attenuation of atrial fibrosis collagen protein markers and transforming growth factor-β1. Additionally, ACE2 overexpression also modulated the tachypacing-induced up-regulation of connexin 40, down-regulation of connexin 43 and Kv4.2, and significantly decreased the inducibility and duration of AF. ACE2 overexpression could shift the renin-angiotensin system balance towards the protective axis, attenuate cardiac fibrosis remodeling associated with up-regulation of MKP-1 and reduction of MAPKs activities, modulate tachypacing-induced ion channels and connexin remodeling, and subsequently reduce the inducibility and duration of AF.

  6. [Individual Progress Program for the Extremely Gifted Student in the Greater Seattle Area.

    ERIC Educational Resources Information Center

    Norsen, Barbara G.; Wick, Christine

    The Individual Progress Program (IPP) is an approach designed to serve extremely advanced gifted students (grades 1 through 9) in the Seattle area. IPP is intended to meet students' unmet educational needs by allowing them to progress at their own accelerated pace through a broadly based curriculum while also pursuing interest areas. The program…

  7. Canine left ventricle electromechanical behavior under different pacing modes.

    PubMed

    Vo Thang, Thanh-Thuy; Thibault, Bernard; Finnerty, Vincent; Pelletier-Galarneau, Matthieu; Khairy, Paul; Grégoire, Jean; Harel, François

    2012-10-01

    Cardiac resynchronization therapy may improve survival and quality of life in patients suffering from heart failure with left ventricular (LV) contraction dyssynchrony. While several studies have investigated electrical or mechanical determinants of synchronous contraction, few have focused on activation contraction coupling at a macroscopic level. The objective of the study was to characterize LV electromechanical behavior and response to pacing in a heart failure model. We analyzed data from 3D electroanatomic non-contact mapping and blood pool SPECT for 12 dogs with right ventricular (RV) tachycardia pacing-induced dilated cardiomyopathy. Surfaces generated by the two modalities were registered. Electrical signals were analyzed, and endocardial wall displacement curves were portrayed. Rapid pacing decreased the mean LV ejection fraction (LVEF) to 20.9 % and prolonged the QRS duration to 79 ± 10 ms (normal range: 40-50 ms). QRS duration remained unchanged with biventricular pacing (88.5 ms), while single site pacing further prolonged the QRS duration (113.3 ms for RV pacing and 111.6 ms for LV pacing). No trend was observed in LV systolic function. Activation duration time was significantly increased with all pacing modes compared to baseline. Finally, electromechanical delay, as defined by the delay between electrical activation and mechanical response, was increased by single site pacing (172.9 ms for RV pacing and 174.6 ms for LV pacing) but not by biventricular pacing (162.4 ms). Combined temporal and spatial coregistration electroanatomic maps and baseline gated blood pool SPECT imaging allowed us to quantify activation duration time, electromechanical delay, and LVEF for different pacing modes. Even if pacing modes did not significantly modify LVEF or activation duration, they produced alterations in electromechanical delay, with biventricular pacing significantly decreasing the electromechanical delay as measured by surface tracings and endocardial non-contact mapping.

  8. An evaluation of the use of new Doppler methods for detecting longitudinal function abnormalities in a pacing-induced heart failure model

    NASA Technical Reports Server (NTRS)

    Tabata, Tomotsugu; Cardon, Lisa A.; Armstrong, Guy P.; Fukamach, Kiyotaka; Takagaki, Masami; Ochiai, Yoshie; McCarthy, Patrick M.; Thomas, James D.

    2003-01-01

    BACKGROUND: Doppler tissue echocardiography and color M-mode Doppler flow propagation velocity have proven useful in evaluating cross-sections of patients with left ventricular (LV) dysfunction, but experience with serial changes is limited. Purpose and methods: We tested their use by evaluating the temporal changes of LV function in a pacing-induced congestive heart failure model. Rapid ventricular pacing was initiated and maintained in 20 dogs for 4 weeks. Echocardiography was performed at baseline and weekly during brief pacing cessation. RESULTS: With rapid pacing, LV volume significantly increased and ejection fraction (57%-28%), stroke volume (37-18 mL), and mitral annulus systolic velocity (16.1-6.6 cm/s) by Doppler tissue echocardiography significantly decreased, with ejection fraction and mitral annulus systolic velocity closely correlated (r = 0.706, P <.0001). In contrast to the mitral inflow velocities, mitral annulus early diastolic velocity decreased steadily (12.3-7.3 cm/s) resulting in a dramatic decrease in mitral annulus early/late (1.22-0.57) diastolic velocity with no tendency toward pseudonormalization. The color M-mode Doppler flow propagation velocity also showed significant steady decrease (57-24 cm/s) throughout the pacing period. Multiple regression analysis chose mitral annulus systolic velocity (r = 0.895, P <.0001) and propagation velocity (r = 0.782, P <.0001) for the most important factor predicting LV systolic and diastolic function, respectively. CONCLUSIONS: Doppler tissue echocardiography and color M-mode Doppler flow could evaluate the serial deterioration in LV dysfunction throughout the pacing period. These were more useful in quantifying progressive LV dysfunction than conventional ehocardiographic techniques, and were probably relatively independent of preload. These techniques could be suitable for longitudinal evaluation in addition to the cross-sectional study.

  9. Inside the Web: A Look at Digital Libraries and the Invisible/Deep Web

    ERIC Educational Resources Information Center

    Su, Mila C.

    2009-01-01

    The evolution of the Internet and the World Wide Web continually exceeds expectations with the "swift pace" of technological innovations. Information is added, and just as quickly becomes outdated at a rapid pace. Researchers have found that Digital materials can provide access to primary source materials and connect the researcher to institutions…

  10. Rapid shifts in South American montane climates driven by pCO2 and ice volume changes over the last two glacial cycles

    NASA Astrophysics Data System (ADS)

    Groot, M. H. M.; Bogotá, R. G.; Lourens, L. J.; Hooghiemstra, H.; Vriend, M.; Berrio, J. C.; Tuenter, E.; van der Plicht, J.; van Geel, B.; Ziegler, M.; Weber, S. L.; Betancourt, A.; Contreras, L.; Gaviria, S.; Giraldo, C.; González, N.; Jansen, J. H. F.; Konert, M.; Ortega, D.; Rangel, O.; Sarmiento, G.; Vandenberghe, J.; van der Hammen, T.; van der Linden, M.; Westerhoff, W.

    2010-10-01

    Tropical montane biome migration patterns in the northern Andes are found to be coupled to glacial-induced mean annual temperature (MAT) changes; however, the accuracy and resolution of current records are insufficient to fully explore their magnitude and rates of change. Here we present a ~60-year resolution pollen record over the past 284 000 years from Lake Fúquene (5° N) in Colombia. This record shows rapid and extreme MAT changes at 2540 m elevation of up to 10 ± 2 °C within a few hundred of years that concur with the ~100 and 41-kyr (obliquity) paced glacial cycles and North Atlantic abrupt climatic events as documented in ice cores and marine sediments. Using transient climate modelling experiments we demonstrate that insolation-controlled ice volume and greenhouse gasses are the major forcing agents causing the orbital MAT changes, but that the model simulations significantly underestimate changes in lapse rates and local hydrology and vegetation feedbacks within the studied region due to its low spatial resolution.

  11. [The use of auto mode switching in patients with sick sinus syndrome].

    PubMed

    Vlasínová, J

    2005-01-01

    At present the dual chamber pacing, originally developed for patients with AV blockades, is widely used also for patients with Sick sinus syndrome (tachycardic-bradycardic type). But these patients often cause therapeutical problems to their physicians. In these cases either antiarrhythmic therapy is necessary to prevent recurrent supraventricular tachycardias (which are cause of rapid ventricular pacing) or in the case of failure of AA therapy the pacing mode has to be changed to DDI/R, which excludes physiological VAT pacing. The Auto Mode Switching (AMS) function ensures adequate ventricular pacing rate in the time of SV arrhythmias. Effects of dual chamber pacemakers equipped with AMS were studied in a group of patients with paroxysmal atrial fibrilation and/or atrial flutter. Therapy brings effects in lower of expenses due to less frequent visits at the physician, lower rate of rehospitalizations and lower need for powerful AA therapy.

  12. Limits to health adaptation in a changing climate

    NASA Astrophysics Data System (ADS)

    Ebi, K. L.

    2015-12-01

    Introduction: Because the health risks of climate variability and change are not new, it has been assumed that health systems have the capacity, experience, and tools to effectively adapt to changing burdens of climate-sensitive health outcomes with additional climate change. However, as illustrated in the Ebola crisis, health systems in many low-income countries have insufficient capacity to manage current health burdens. These countries also are those most vulnerable to climate change, including changes in food and water safety and security, increases in extreme weather and climate events, and increases in the geographic range, incidence, and seasonality of a variety of infectious diseases. The extent to which they might be able to keep pace with projected risks depends on assumptions of the sustainability of development pathways. At the same time, the magnitude and pattern of climate change will depend on greenhouse gas emission pathways. Methods: Review of the success of health adaptation projects and expert judgment assessment of the degree to which adaptation efforts will be able to keep pace with projected changes in climate variability and change. Results: Health adaptation can reduce the current and projected burdens of climate-sensitive health outcomes over the short term in many countries, but the extent to which it could do so past mid-century will depend on emission and development pathways. Under high emission scenarios, climate change will be rapid and extensive, leading to fundamental shifts in the burden of climate-sensitive health outcomes that will challenging for many countries to manage. Sustainable development pathways could delay but not eliminate associated health burdens. Conclusions: To prepare for and cope with the Anthropocene, health systems need additional adaptation policies and measures to develop more robust health systems, and need to advocate for rapid and significant reductions in greenhouse gas emissions.

  13. Dorsal spinal cord stimulation obtunds the capacity of intrathoracic extracardiac neurons to transduce myocardial ischemia

    PubMed Central

    Ardell, Jeffrey L.; Cardinal, René; Vermeulen, Michel; Armour, J. Andrew

    2009-01-01

    Populations of intrathoracic extracardiac neurons transduce myocardial ischemia, thereby contributing to sympathetic control of regional cardiac indices during such pathology. Our objective was to determine whether electrical neuromodulation using spinal cord stimulation (SCS) modulates such local reflex control. In 10 anesthetized canines, middle cervical ganglion neurons were identified that transduce the ventricular milieu. Their capacity to transduce a global (rapid ventricular pacing) vs. regional (transient regional ischemia) ventricular stress was tested before and during SCS (50 Hz, 0.2 ms duration at 90% MT) applied to the dorsal aspect of the T1 to T4 spinal cord. Rapid ventricular pacing and transient myocardial ischemia both activated cardiac-related middle cervical ganglion neurons. SCS obtunded their capacity to reflexly respond to the regional ventricular ischemia, but not rapid ventricular pacing. In conclusion, spinal cord inputs to the intrathoracic extracardiac nervous system obtund the latter's capacity to transduce regional ventricular ischemia, but not global cardiac stress. Given the substantial body of literature indicating the adverse consequences of excessive adrenergic neuronal excitation on cardiac function, these data delineate the intrathoracic extracardiac nervous system as a potential target for neuromodulation therapy in minimizing such effects. PMID:19515981

  14. Extraordinarily rapid speciation in a marine fish

    PubMed Central

    Momigliano, Paolo; Jokinen, Henri; Fraimout, Antoine; Florin, Ann-Britt; Norkko, Alf; Merilä, Juha

    2017-01-01

    Divergent selection may initiate ecological speciation extremely rapidly. How often and at what pace ecological speciation proceeds to yield strong reproductive isolation is more uncertain. Here, we document a case of extraordinarily rapid speciation associated with ecological selection in the postglacial Baltic Sea. European flounders (Platichthys flesus) in the Baltic exhibit two contrasting reproductive behaviors: pelagic and demersal spawning. Demersal spawning enables flounders to thrive in the low salinity of the Northern Baltic, where eggs cannot achieve neutral buoyancy. We show that demersal and pelagic flounders are a species pair arising from a recent event of speciation. Despite having a parapatric distribution with extensive overlap, the two species are reciprocally monophyletic and show strongly bimodal genotypic clustering and no evidence of contemporary migration, suggesting strong reproductive isolation. Divergence across the genome is weak but shows strong signatures of selection, a pattern suggestive of a recent ecological speciation event. We propose that spawning behavior in Baltic flounders is the trait under ecologically based selection causing reproductive isolation, directly implicating a process of ecological speciation. We evaluated different possible evolutionary scenarios under the approximate Bayesian computation framework and estimate that the speciation process started in allopatry ∼2,400 generations ago, following the colonization of the Baltic by the demersal lineage. This is faster than most known cases of ecological speciation and represents the most rapid event of speciation ever reported for any marine vertebrate. PMID:28533412

  15. Blueprint for a Better World...A Book That Introduces a New, Simpler, Comprehensive Method of Understanding Our Environment. Rough Draft.

    ERIC Educational Resources Information Center

    Richards, David B.

    The world is growing technologically at a rapid pace and people's understanding of these new technological advances and their effects upon the world and its various populations and environments must keep up the pace. Technological advances bring with them ever greater potential problems for humanity and for the world environment. The complications…

  16. Changing reward systems for team-based systems.

    PubMed

    Barksdale, G T

    1998-12-01

    With the rapidly changing pace in health care, hospitals are struggling to keep costs under control and to remain competitive. Leadership is increasingly convinced that old methods of compensation are no longer valid and thus are turning to innovative approaches to pay and reward systems. This article describes some of the new pay methods, with an emphasis on team rewards, showing that compensation can keep pace with the evolving needs of health care.

  17. Pakistan: Energy Development and Economic Growth in the 1980s

    DTIC Science & Technology

    1995-01-01

    factors can obstruct a rapid pace of economic development.! Scarcities of capital, a skilled and disci- plined labour force, entrepreneurial talent...foreign exchange and industrial raw ma- terials have been mentioned, among the prominent obstacles to growth in unde- veloped countries . Lack of adequate...energy supply is now being added as a factor explaining the slow pace of growth in these countries . For a large number of less developed countries have

  18. Valsartan Reduced Atrial Fibrillation Susceptibility by Inhibiting Atrial Parasympathetic Remodeling through MAPKs/Neurturin Pathway.

    PubMed

    Liu, Lei; Geng, Jianqiang; Zhao, Hongwei; Yun, Fengxiang; Wang, Xiaoyu; Yan, Sen; Ding, Xue; Li, Wenpeng; Wang, Dingyu; Li, Jianqiang; Pan, Zhenwei; Gong, Yongtai; Tan, Xiangyang; Li, Yue

    2015-01-01

    Angiotensin II receptor blockers (ARBs) have been proved to be effective in preventing atrial structural and electrical remodelinq in atrial fibrillation (AF). Previous studies have shown that parasympathetic remodeling plays an important role in AF. However, the effects of ARBs on atrial parasympathetic remodeling in AF and the underlying mechanisms are still unknown. Canines were divided into sham-operated, pacing and valsartan + pacing groups. Rats and HL-1 cardiomyocytes were divided into control, angiotensin II (Ang II) and Ang II + valsartan groups, respectively. Atrial parasympathetic remodeling was quantified by immunocytochemical staining with anti-choline acetyltransferase (ChAT) antibody. Western blot was used to analysis the protein expression of neurturin. Both inducibility and duration were increased in chronic atrial rapid-pacing canine model, which was significantly inhibited by the treatment with valsartan. The density of ChAT-positive nerves and the protein level of neurturin in the atria of pacing canines were both increased than those in sham-operated canines. Ang II treatment not only induced atrial parasympathetic remodeling in rats, but also up-regulated the protein expression of neurturin. Valsartan significantly prevented atrial parasympathetic remodeling, and suppressed the protein expression of neurturin. Meanwhile, valsartan inhibited Ang II -induced up-regulation of neurturin and MAPKs in cultured cardiac myocytes. Inhibition of MAPKs dramatically attenuated neurturin up-regulation induced by Ang II. Parasympathetic remodeling was present in animals subjected to rapid pacing or Ang II infusion, which was mediated by MAPKs/neurturin pathway. Valsartan is able to prevent atrial parasympathetic remodeling and the occurrence of AF via inhibiting MAPKs/neurturin pathway. © 2015 S. Karger AG, Basel.

  19. Effect of normal-walking-pattern-based functional electrical stimulation on gait of the lower extremity in subjects with ischemic stroke: A self controlled study.

    PubMed

    Xu, Benlei; Yan, Tiebin; Yang, Yuanle; Ou, Ruiqing; Huang, Shuping

    2016-01-01

    Functional electrical stimulation is a widely used technique for rehabilitation. To assess the efficacy of walking-pattern-based four-channel functional electric stimulation and its influence on the gait features of stroke patients with hemiplegia. A total of 21 stroke patients with hemiplegia were enrolled into the study. The walking gaits of patients were investigated before, during and after walking-pattern-based FES treatment using the gait analysis system. The changes of gait indexes were comparatively analyzed. After walking-pattern-based FES therapy, the pace, stride rate, gait cycle, and step length of stroke patients with hemiplegia were 50.19 ± 14.45 cm/s, 36.85 ± 5.85 time/min, 1.6643 ± 0.2626 sec, 80.3333 ± 15.1438 cm, respectively. The motion range of hip and knee joint were 47.5238 ± 10.7453, 56.7619 ± 14.5255, respectively. We found these indexes were significantly improved compared with those before FES treatment (P <  0.05). The single swing rate (injured extremity/uninjured extremity) after FES treatment was 1.5589 ± 0.4550. The statistical results showed that the gait cycle, pace, stride rat, and single swing rate (injured extremity/uninjured extremity) were significantly improved after FES treatment (P <  0.05). Our results demonstrate that walking-paradigm based FES we developed is effective for treating stroke patients during rehabilitation.

  20. Computational Toxicology in Cancer Risk Assessment

    EPA Science Inventory

    Risk assessment over the last half century has, for many individual cases served us well, but has proceeded on an extremely slow pace and has left us with considerable uncertainty. There are certainly thousands of compounds and thousands of exposure scenarios that remain unteste...

  1. Pacing-induced chronic atrial fibrillation impairs sinus node function in dogs. Electrophysiological remodeling.

    PubMed

    Elvan, A; Wylie, K; Zipes, D P

    1996-12-01

    We assessed the effects of pacing-induced chronic atrial fibrillation (AF) on sinus node function, intra-atrial conduction, and atrial refractoriness. In 15 mongrel dogs (20 to 30 kg), AV nodal block was produced by radiofrequency catheter ablation, and a ventricular-inhibited (VVI) pacemaker (Minix 8330, Medtronic) was implanted and programmed to pace at 80 pulses per minute. In 11 of these dogs, right atrial endocardial pacing leads were connected to a pulse generator (Itrel 7432, Medtronic) and set at a rate of 20 Hz to induce AF. Corrected sinus node recovery time, P-wave duration, 24-hour Holter ECG to assess AF duration, maximal heart rate in response to isoproterenol (10 micrograms/min), intrinsic heart rate after administration of atropine (0.04 mg/kg) and propranolol (0.1 mg/kg), and atrial effective refractory periods (ERPs) were obtained at baseline (EPS-1) and after 2 to 6 weeks (EPS-2) of VVI pacing alone (n = 4) or VVI pacing and rapid atrial pacing (n = 11). At EPS-2, corrected sinus node recovery time and P-wave duration were prolonged, maximal heart rate and intrinsic heart rate were decreased, atrial ERPs were shortened, and the duration of AF was increased significantly compared with EPS-1. These changes partially reversed toward baseline 1 week after conversion to sinus rhythm. Sinus node function and AF inducibility observed in the control dogs that underwent ventricular pacing alone (n = 4) did not change. Pacing-induced chronic AF induces sinus node dysfunction, prolongs intra-atrial conduction time, shortens atrial refractoriness, and perpetuates AF, changes that reverse gradually after termination of AF.

  2. The metabolic pace-of-life model: incorporating ectothermic organisms into the theory of vertebrate ecoimmunology.

    PubMed

    Sandmeier, Franziska C; Tracy, Richard C

    2014-09-01

    We propose a new heuristic model that incorporates metabolic rate and pace of life to predict a vertebrate species' investment in adaptive immune function. Using reptiles as an example, we hypothesize that animals with low metabolic rates will invest more in innate immunity compared with adaptive immunity. High metabolic rates and body temperatures should logically optimize the efficacy of the adaptive immune system--through rapid replication of T and B cells, prolific production of induced antibodies, and kinetics of antibody--antigen interactions. In current theory, the precise mechanisms of vertebrate immune function oft are inadequately considered as diverse selective pressures on the evolution of pathogens. We propose that the strength of adaptive immune function and pace of life together determine many of the important dynamics of host-pathogen evolution, namely, that hosts with a short lifespan and innate immunity or with a long lifespan and strong adaptive immunity are expected to drive the rapid evolution of their populations of pathogens. Long-lived hosts that rely primarily on innate immune functions are more likely to use defense mechanisms of tolerance (instead of resistance), which are not expected to act as a selection pressure for the rapid evolution of pathogens' virulence. © The Author 2014. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  3. The Pace of Perceivable Extreme Climate Change

    NASA Astrophysics Data System (ADS)

    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.

  4. An Active Reading Intervention for the Electronic Career Development Course (eCDC) Program

    ERIC Educational Resources Information Center

    Isreal, Kenith R.

    2013-01-01

    Electronic books have rapidly moved through the entertainment community and are rapidly making their way into the academic environment. Public and private schools, libraries and training organizations use eBooks for research and instruction. This study sought to enhance the learning habits of students taking self-paced correspondence courses…

  5. Spatiotemporal trends in extreme rainfall and temperature indices over Upper Tapi Basin, India

    NASA Astrophysics Data System (ADS)

    Sharma, Priyank J.; Loliyana, V. D.; S. R., Resmi; Timbadiya, P. V.; Patel, P. L.

    2017-12-01

    The flood risk across the globe is intensified due to global warming and subsequent increase in extreme temperature and precipitation. The long-term trends in extreme rainfall (1944-2013) and temperature (1969-2012) indices have been investigated at annual, seasonal, and monthly time scales using nonparametric Mann-Kendall (MK), modified Mann-Kendall (MMK), and Sen's slope estimator tests. The extreme rainfall and temperature indices, recommended by the Expert Team on Climate Change Detection Monitoring Indices (ETCCDMI), have been analyzed at finer spatial scales for trend detection. The results of trend analyses indicate decreasing trend in annual total rainfall, significant decreasing trend in rainy days, and increasing trend in rainfall intensity over the basin. The seasonal rainfall has been found to decrease for all the seasons except postmonsoon, which could affect the rain-fed agriculture in the basin. The 1- and 5-day annual maximum rainfalls exhibit mixed trends, wherein part of the basin experiences increasing trend, while other parts experience a decreasing trend. The increase in dry spells and concurrent decrease in wet spells are also observed over the basin. The extreme temperature indices revealed increasing trends in hottest and coldest days, while decreasing trends in coldest night are found over most parts of the basin. Further, the diurnal temperature range is also found to increase due to warming tendency in maximum temperature (T max) at a faster rate compared to the minimum temperature (T min). The increase in frequency and magnitude of extreme rainfall in the basin has been attributed to the increasing trend in maximum and minimum temperatures, reducing forest cover, rapid pace of urbanization, increase in human population, and thereby increase in the aerosol content in the atmosphere. The findings of the present study would significantly help in sustainable water resource planning, better decision-making for policy framework, and setting up infrastructure against flood disasters in Upper Tapi Basin, India.

  6. The effects of hypoxemia on myocardial blood flow during exercise.

    PubMed

    Paridon, S M; Bricker, J T; Dreyer, W J; Reardon, M; Smith, E O; Porter, C B; Michael, L; Fisher, D J

    1989-03-01

    We evaluated the adequacy of regional and transmural blood flow during exercise and rapid pacing after 1 wk of hypoxemia. Seven mature mongrel dogs were made hypoxemic (mean O2 saturation = 72.4%) by anastomosis of left pulmonary artery to left atrial appendage. Catheters were placed in the left atrium, right atrium, pulmonary artery, and aorta. Atrial and ventricular pacing wires were placed. An aortic flow probe was placed to measure cardiac output. Ten nonshunted dogs, similarly instrumented, served as controls. Recovery time was approximately 1 wk. Cardiac output, mean aortic pressure, and oxygen saturation were measured at rest, with ventricular pacing, atrial pacing, and with treadmill exercise. Ventricular and atrial pace and exercise were at a heart rate of 200. Right ventricular free wall, left ventricular free wall, and septal blood flow were measured with radionuclide-labeled microspheres. Cardiac output, left atrial blood pressure, and aortic blood pressure were similar between the two groups of dogs in all testing states. Myocardial blood flow was significantly higher in the right and left ventricular free wall in the hypoxemic animals during resting and exercise testing states. Myocardial oxygen delivery was similar between the two groups of animals. Pacing resulted in an increase in myocardial blood flow in the control animals but not the hypoxemic animals.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. [Influence of pacing site on myocardial transmural dispersion of repolarization in intact normal and dilated cardiomyopathy dogs].

    PubMed

    Bai, Rong; Pu, Jun; Liu, Nian; Lu, Jia-Gao; Zhou, Qiang; Ruan, Yan-Fei; Niu, Hui-Yan; Wang, Lin

    2003-12-25

    In order to verify the hypothesis that left ventricular epicardial (LV-Epi) pacing and biventricular (BiV) pacing unavoidably influence the myocardial electrophysiological characters and may result in high risk of malignant ventricular arrhythmia, we calculated, in both normal mongrel dogs and dog models with rapid-right-ventricular-pacing induced dilated cardiomyopathy congestive heart failure (DCM-CHF), the monophasic action potential duration (MAPD) and the transmural dispersion of repolarization (TDR) in intracardiac electrogram together with the QT interval and T(peak)-T(end) (T(p(-T(e)) interval in surface electrocardiogram (ECG) during LV-Epi and BiV pacing, compared with those during right ventricular endocardial (RV-Endo) pacing. To prepare the DCM-CHF dog model, rapid right ventricular pacing (250 bpm) was performed for 23.6+/-2.57 days to the dog. All the normal and DCM-CHF dogs were given radio frequency catheter ablation (RFCA) to His bundle with the guide of X-ray fluoroscopy. After the RFCA procedures, the animals were under the situation of complete atrioventricular block so that the canine heart rates could be voluntarily controlled in the following experiments. After a thoracotomy, ECG and monophasic action potentials (MAP) of subendocardial, subepicardial and mid-layer myocardium were recorded synchronously in 8 normal and 5 DCM-CHF dogs during pacing from endocardium of RV apex (RV-Endo), epicardium of LV anterior wall (LV-Epi) and simultaneously both of the above (biventricular, BiV), the later was similar to the ventricular resynchronization therapy to congestive heart failure patients in clinic. The Tp-Te) meant the interval from the peak to the end of T wave, which was a representative index of TDR in surface ECG. The TDR was defined as the difference between the longest and the shortest MAPD of subendocardial, subepicardial and mid-layer myocardium. Our results showed that in normal dogs, pacing participating of LV (LV-Epi, BiV) prolonged MAPD of all the three layers of the myocardium (P<0.05) with the character that mid-layer MAPD was the longest and subepicardial MAPD was the shortest following subendocardial MAPD. At the same time, TDR prolonged from 26.75 ms at RV-Endo pacing to 37.54 ms at BiV pacing and to 47.16 ms at LV-Epi pacing (P<0.001). Meanwhile in surface ECG, BiV and LV-Epi pacing resulted in a longer Tp-Te) interval compared with RV-Endo pacing (P<0.01), without parallel QT interval prolongation. Furthermore, all the DCM-CHF model dogs showed manifestations of congestive heart failure and enlargement of left ventricles. Based on the lengthening of mid-layer MAPD from 257.35 ms to 276.30 ms (P<0.0001) and increase of TDR from 27.58 ms to 33.80 ms (P equals;0.002) in DCM-CHF model due to the structural disorders of myocardium compared with the normal dog, LV-Epi and BiV pacing also led to the effect of prolonging MAPD of three layers of the myocardium and enlarging TDR. From these results we make the conclusions that prolongation of MAPD of subendocardial, subepicardial and mid-layer myocardium and increase in TDR during pacing participating of LV (LV-Epi, BiV) may contribute to the formation of unidirectional block and reentry, which play roles or at least are the high risk factors in the development of malignant ventricular arrhythmia, especially in case of structural disorders of myocardium. These findings must be considered seriously when ventricular resynchronization therapy is performed to congestive heart failure patients.

  8. Mindful Organizing as a Paradigm to Develop Managers

    ERIC Educational Resources Information Center

    Gebauer, Annette

    2013-01-01

    How can managers prepare for extreme but exceptional events and for the challenge of managing complexity and uncertainty in their daily business? Confronted with the challenge of achieving high and reliable performance in risk-prone, fast-paced, and unpredictable environments, managers and management scholars can learn a lot from the organizing…

  9. Left ventricular epicardial activation increases transmural dispersion of repolarization in healthy, long QT, and dilated cardiomyopathy dogs.

    PubMed

    Bai, Rong; Lü, Jiagao; Pu, Jun; Liu, Nian; Zhou, Qiang; Ruan, Yanfei; Niu, Huiyan; Zhang, Cuntai; Wang, Lin; Kam, Ruth

    2005-10-01

    Benefits of cardiac resynchronization therapy (CRT) are well established. However, less is understood concerning its effects on myocardial repolarization and the potential proarrhythmic risk. Healthy dogs (n = 8) were compared to a long QT interval (LQT) model (n = 8, induced by cesium chloride, CsCl) and a dilated cardiomyopathy with congestive heart failure (DCM-CHF, induced by rapid ventricular pacing, n = 5). Monophasic action potential (MAP) recordings were obtained from the subendocardium, midmyocardium, subepicardium, and the transmural dispersion of repolarization (TDR) was calculated. The QT interval and the interval from the peak to the end of the T wave (T(p-e)) were measured. All these characteristics were compared during left ventricular epicardial (LV-Epi), right ventricular endocardial (RV-Endo), and biventricular (Bi-V) pacing. In healthy dogs, TDR prolonged to 37.54 ms for Bi-V pacing and to 47.16 ms for LV-Epi pacing as compared to 26.75 ms for RV-Endo pacing (P < 0.001), which was parallel to an augmentation in T(p-e) interval (Bi-V pacing, 64.29 ms; LV-Epi pacing, 57.89 ms; RV-Endo pacing, 50.29 ms; P < 0.01). During CsCl exposure, Bi-V and LV-Epi pacing prolonged MAPD, TDR, and T(p-e) interval as compared to RV-Endo pacing. The midmyocardial MAPD (276.30 ms vs 257.35 ms, P < 0.0001) and TDR (33.80 ms vs 27.58 ms, P=0.002) were significantly longer in DCM-CHF dogs than those in healthy dogs. LV-Epi and Bi-V pacing further prolonged the MAPD and TDR in this model. LV-Epi and Bi-V pacing result in prolongation of ventricular repolarization time, and increase of TDR accounted for a parallel augmentation of the T(p-e) interval, which provides evidence that T(p-e) interval accurately represents TDR. These effects are magnified in the LQT and DCM-CHF canine models in addition to their intrinsic transmural heterogeneity in the intact heart. This mechanism may contribute to the development of malignant ventricular arrhythmias, such as torsades de pointes (TdP) in congestive heart failure (CHF) patients treated with CRT.

  10. Newborn Jaundice Technologies: Unbound Bilirubin and Bilirubin Binding Capacity In Neonates

    PubMed Central

    Amin, Sanjiv B.; Lamola, Angelo A.

    2011-01-01

    Neonatal jaundice (hyperbilirubinemia), extremely common in neonates, can be associated with neurotoxicity. A safe level of bilirubin has not been defined in either premature or term infants. Emerging evidence suggest that the level of unbound (or “free”) bilirubin has a better sensitivity and specificity than total serum bilirubin for bilirubin-induced neurotoxicity. Although recent studies suggest the usefulness of free bilirubin measurements in managing high-risk neonates including premature infants, there currently exists no widely available method to assay the serum free bilirubin concentration. To keep pace with the growing demand, in addition to reevaluation of old methods, several promising new methods are being developed for sensitive, accurate, and rapid measurement of free bilirubin and bilirubin binding capacity. These innovative methods need to be validated before adopting for clinical use. We provide an overview of some promising methods for free bilirubin and binding capacity measurements with the goal to enhance research in this area of active interest and apparent need. PMID:21641486

  11. The fast food and obesity link: consumption patterns and severity of obesity.

    PubMed

    Garcia, Ginny; Sunil, Thankam S; Hinojosa, Pedro

    2012-05-01

    Rates of extreme forms of obesity are rapidly rising, as is the use of bariatric surgery for its treatment. The aim of the present study was to examine selected behavioral factors associated with severity of obesity among preoperative bariatric surgery patients in the San Antonio area, focusing specifically on the effects of fast food consumption. We used ordered logistic regression to model behavioral and attitudinal effects on obesity outcomes among 270 patients. These outcomes were based on the severity of obesity and were measured on the basis of body mass index. Our results indicated that, among the behavioral factors, fast food consumption exerted the largest influence on higher levels of obesity. These remained after controlling for several social and demographic characteristics. Our findings suggest that higher rates of fast food consumption are connected to the increasing rates of severe obesity. Given that morbid and super morbid obesity rates are growing at a more advanced pace than moderate obesity, it is necessary to explore the behavioral characteristics associated with these trends.

  12. Output ordering and prioritisation system (OOPS): ranking biosynthetic gene clusters to enhance bioactive metabolite discovery.

    PubMed

    Peña, Alejandro; Del Carratore, Francesco; Cummings, Matthew; Takano, Eriko; Breitling, Rainer

    2017-12-18

    The rapid increase of publicly available microbial genome sequences has highlighted the presence of hundreds of thousands of biosynthetic gene clusters (BGCs) encoding valuable secondary metabolites. The experimental characterization of new BGCs is extremely laborious and struggles to keep pace with the in silico identification of potential BGCs. Therefore, the prioritisation of promising candidates among computationally predicted BGCs represents a pressing need. Here, we propose an output ordering and prioritisation system (OOPS) which helps sorting identified BGCs by a wide variety of custom-weighted biological and biochemical criteria in a flexible and user-friendly interface. OOPS facilitates a judicious prioritisation of BGCs using G+C content, coding sequence length, gene number, cluster self-similarity and codon bias parameters, as well as enabling the user to rank BGCs based upon BGC type, novelty, and taxonomic distribution. Effective prioritisation of BGCs will help to reduce experimental attrition rates and improve the breadth of bioactive metabolites characterized.

  13. Speed-Dependent Contribution of Callosal Pathways to Ipsilateral Movements

    PubMed Central

    Tazoe, Toshiki

    2013-01-01

    Transcallosal inhibitory interactions between primary motor cortices are important to suppress unintended movements in a resting limb during voluntary activation of the contralateral limb. The functional contribution of transcallosal inhibition targeting the voluntary active limb remains unknown. Using transcranial magnetic stimulation, we examined transcallosal inhibition [by measuring interhemispheric inhibition (IHI) and the ipsilateral silent period (iSP)] in the preparatory and execution phases of isotonic slower self-paced and ballistic movements performed by the ipsilateral index finger into abduction and the elbow into flexion in intact humans. We demonstrate decreased IHI in the preparatory phase of self-paced and ballistic index finger and elbow movements compared to rest; the decrease in IHI was larger during ballistic than self-paced movements. In contrast, in the execution phase, IHI and the iSP increased during ballistic compared to self-paced movements. Transcallosal inhibition was negatively correlated with reaction times in the preparatory phase and positively correlated with movement amplitude in the execution phase. Together, our results demonstrate a widespread contribution of transcallosal inhibition to ipsilateral movements of different speeds with a functional role during rapid movements; at faster speeds, decreased transcallosal inhibition in the preparatory phase may contribute to start movements rapidly, while the increase in the execution phase may contribute to stop the movement. We argue that transcallosal pathways enable signaling of the time of discrete behavioral events during ipsilateral movements, which is amplified by the speed of a movement. PMID:24107950

  14. Repetitive nonreentrant ventriculoatrial synchrony: An underrecognized cause of pacemaker-related arrhythmia.

    PubMed

    Sharma, Parikshit S; Kaszala, Karoly; Tan, Alex Y; Koneru, Jayanthi N; Shepard, Richard; Ellenbogen, Kenneth A; Huizar, Jose F

    2016-08-01

    Similar to endless loop tachycardia (ELT), repetitive nonreentrant ventriculoatrial synchrony (RNRVAS) is a ventriculoatrial (VA) synchrony pacemaker-mediated arrhythmia. RNRVAS was first described in 1990 and can only occur in the presence of retrograde VA conduction and dual-chamber or cardiac resynchronization devices with tracking (P-synchronous ventricular pacing such as DDD, DDDR) or nontracking pacing modes that allow AV-sequential pacing (DDI, DDIR). RNRVAS is promoted by (1) high lower rate limit or any feature that allows rapid pacing, (2) long AV intervals, or (3) long postventricular atrial refractory period (PVARP). In contrast to ELT, RNRVAS is a less well-recognized form of pacemaker-mediated arrhythmia; thus, unlike ELT, there are no specific device algorithms to prevent, recognize, and terminate RNRVAS. However, RNRVAS has been recently shown to occur frequently. We present a series of cases, some of which were found fortuitously. Owing to its clinical implications, we propose that algorithms should be developed to prevent, identify, and terminate RNRVAS. Published by Elsevier Inc.

  15. Social Security Disability Insurance: Time for Fundamental Change

    ERIC Educational Resources Information Center

    Burkhauser, Richard V.; Daly, Mary C.

    2012-01-01

    The Social Security Disability Insurance (SSDI) program is growing at an unsustainable pace. Over the past 40 years the number of disabled worker beneficiaries has increased nearly sixfold, rising from 1.5 million in 1970 to 8.2 million in 2010. Rapid growth in the rolls has put increasing pressure on program finances. The rapid rise in SSDI…

  16. Recent advances in pacemaker and implantable defibrillator therapy for young patients.

    PubMed

    Walsh, Edward P; Cecchin, Frank

    2004-03-01

    This review is intended to highlight major clinical advances over the past year related to (1). biventricular pacing as a treatment for dilated myopathy, (2). growing clinical experience with implantable cardioverter defibrillators in pediatrics, (3). technical advances in standard antibradycardia pacing, and (4). an appraisal of the newly updated ACC/AHA/NASPE guidelines for device implant in children and adolescents. Complex rhythm devices are being used more frequently in children. Biventricular pacing to improve ventricular contractility is a rapidly evolving technology that has now been applied to children and young adults with intraventricular conduction delay, such as bundle branch block after cardiac surgery. Implantable defibrillators are also being used for an expanding list of conditions, although lead dysfunction is seen as a fairly common complication in active young patients. Guidelines for device implantation have been developed, but the weight of evidence remains somewhat limited by the paucity of pediatric data in this field. Thanks to refinements in lead design and generator technology, coupled with rapidly expanding clinical indications, pacemakers and implantable defibrillators have become increasingly important components of cardiac therapy for young patients. Expanded multicenter clinical studies will be needed to develop more objective guidelines for use of this advanced technology.

  17. Intermittent atrial tachycardia promotes repolarization alternans and conduction slowing during rapid rates, and increases susceptibility to atrial fibrillation in a free-behaving sheep model.

    PubMed

    Monigatti-Tenkorang, Joanna; Jousset, Florian; Pascale, Patrizio; Vesin, Jean-Marc; Ruchat, Patrick; Fromer, Martin; Narayan, Sanjiv M; Pruvot, Etienne

    2014-04-01

    Paroxysmal atrial fibrillation (AF) may be triggered by intermittent atrial tachycardia, and ultimately lead to persistent AF. However, the mechanisms by which intermittent atrial tachycardia promotes sustained AF are not well understood. Eight sheep were chronically implanted with 2 pacemakers for the recording of broadband right atrial unipolar electrograms, and for the delivery of electrophysiological stimulation protocols and intermittent right atrial tachycardia. Right atrial kinetics of activation recovery interval (ARI) as a surrogate for action potential duration, of conduction time and velocity, and of repolarization alternans were analyzed at incremental pacing rates during the remodeling process induced by weeks of intermittent atrial tachycardia until the development of sustained AF. Intermittent atrial tachycardia decreased ARI and blunted its rate adaptation, facilitated atrial capture, and slowed conduction at high rates, and increased susceptibility to pacing-induced AF. In spite of blunted ARI rate adaptation, right atrial repolarization alternans was maintained during remodeling, and further increased in magnitude just before rapid pacing-induced AF. This study suggests that weeks of intermittent right atrial tachycardia result in a gradual electrical remodeling favorable for wavebreaks and reentry that may facilitate fibrillation. © 2014 Wiley Periodicals, Inc.

  18. Rapid Evaporation of microbubbles

    NASA Astrophysics Data System (ADS)

    Gautam, Jitendra; Esmaeeli, Asghar

    2008-11-01

    When a liquid is heated to a temperature far above its boiling point, it evaporates abruptly. Boiling of liquid at high temperatures can be explosive and destructive, and poses a potential hazard for a host of industrial processes. Explosive boiling may occur if a cold and volatile liquid is brought into contact with a hot and non-volatile liquid, or if a liquid is superheated or depressurized rapidly. Such possibilities are realized, for example, in the depressurization of low boiling point liquefied natural gas (LNG) in the pipelines or storage tanks as a result of a leak. While boiling of highly heated liquids can be destructive at macroscale, the (nearly) instantaneous pace of the process and the release of large amount of kinetic energy make the phenomena extremely attractive at microscale where it is possible to utilize the released energy to derive micromechanical systems. For instance, there is currently a growing interest in micro-explosion of liquid for generation of micro bubbles for actuation purposes. The aim of the current study is to gain a fundamental understanding of the subject using direct numerical simulations. In particular, we seek to investigate the boundary between stable and unstable nucleus growth in terms of the degree of liquid superheat and to compare the dynamics of unstable and stable growth.

  19. Rapid Experimental Evolution of Pesticide Resistance in C. elegans Entails No Costs and Affects the Mating System

    PubMed Central

    Lopes, Patricia C.; Sucena, Élio; Santos, M. Emília; Magalhães, Sara

    2008-01-01

    Pesticide resistance is a major concern in natural populations and a model trait to study adaptation. Despite the importance of this trait, the dynamics of its evolution and of its ecological consequences remain largely unstudied. To fill this gap, we performed experimental evolution with replicated populations of Caenorhabditis elegans exposed to the pesticide Levamisole during 20 generations. Exposure to Levamisole resulted in decreased survival, fecundity and male frequency, which declined from 30% to zero. This was not due to differential susceptibility of males. Rather, the drug affected mobility, resulting in fewer encounters, probably leading to reduced outcrossing rates. Adaptation, i.e., increased survival and fecundity, occurred within 10 and 20 generations, respectively. Male frequency also increased by generation 20. Adaptation costs were undetected in the ancestral environment and in presence of Ivermectin, another widely-used pesticide with an opposite physiological effect. Our results demonstrate that pesticide resistance can evolve at an extremely rapid pace. Furthermore, we unravel the effects of behaviour on life-history traits and test the environmental dependence of adaptation costs. This study establishes experimental evolution as a powerful tool to tackle pesticide resistance, and paves the way to further investigations manipulating environmental and/or genetic factors underlying adaptation to pesticides. PMID:19011681

  20. Exaggerated cardiovascular effects of cocaine in conscious dogs with pacing-induced dilated cardiomyopathy.

    PubMed

    Mathier, Michael A; Shen, You-Tang; Shannon, Richard P

    2002-12-01

    The aim of this study was to explore the characteristics and mechanisms of the cardiovascular effects of cocaine in dilated cardiomyopathy. We studied the cardiovascular responses to acute intravenous cocaine (1 mg/kg) in 8 conscious, chronically instrumented dogs before and after the development of dilated cardiomyopathy induced by rapid ventricular pacing. To help elucidate the role of altered baroreflex function in mediating the cardiovascular effects of cocaine, we also studied responses in 3 conscious, chronically instrumented dogs that had undergone surgical sinoaortic baroreceptor denervation. Cocaine produced greater increases in heart rate (+57 +/- 8% from 112 +/- 5 beats/min versus +28 +/- 3% from 100 +/- 4 beats/min; P <.01), first derivative of left ventricular pressure (+30 +/- 5% from 1,714 +/- 147 mm Hg/sec versus +15 +/- 3% from 3,032 +/- 199 mm Hg/sec; P <.01), coronary vascular resistance (+28 +/- 5% from 2.3 +/- 0.3 mm Hg/mL/min versus +11 +/- 5% from 2.2 +/- 0.3 mm Hg/mL/min; P <.05) and plasma norepinephrine concentration (+130 +/- 31% from 462 +/- 102 pg/mL versus +86 +/- 32% from 286 +/- 77 pg/mL; P <.05) in dogs with dilated cardiomyopathy as compared to controls. In addition, responses were much more rapid in onset following the development of dilated cardiomyopathy. Chronotropic and inotropic responses to cocaine were similarly rapid and exaggerated in dogs after baroreceptor denervation. Cocaine produces rapid and exaggerated chronotropic, inotropic, and coronary vasoconstrictor responses in conscious dogs with pacing-induced dilated cardiomyopathy. Alterations in arterial baroreflex function may play a role in these observations, which in turn may underlie the clinically observed association between cocaine and heart failure.

  1. Lung Cancer Precision Medicine Trials

    Cancer.gov

    Patients with lung cancer are benefiting from the boom in targeted and immune-based therapies. With a series of precision medicine trials, NCI is keeping pace with the rapidly changing treatment landscape for lung cancer.

  2. Structural analysis of cell wall polysaccharides using PACE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mortimer, Jennifer C.

    The plant cell wall is composed of many complex polysaccharides. The composition and structure of the polysaccharides affect various cell properties including cell shape, cell function and cell adhesion. Many techniques to characterize polysaccharide structure are complicated, requiring expensive equipment and specialized operators e.g. NMR, MALDI-MS. PACE (Polysaccharide Analysis using Carbohydrate gel Electrophoresis) uses a simple, rapid technique to analyze polysaccharide quantity and structure (Goubet et al. 2002). Whilst the method here describes xylan analysis, it can be applied (by use of the appropriate glycosyl hydrolase) to any cell wall polysaccharide.

  3. A Quiet Transformation

    ERIC Educational Resources Information Center

    Dierke, James S.

    2012-01-01

    The author's 40 years as an educator have led him to an important insight: stress is crippling the schools. On top of other extreme conditions in schools and on students, there is the pressure to achieve and succeed in a fast-paced, chaotic world. This pervasive stress compromises the physical health, and in turn the cognitive and psychological…

  4. Ready, Aim, Perform! Targeted Micro-Training for Performance Intervention

    ERIC Educational Resources Information Center

    Carpenter, Julia; Forde, Dahlia S.; Stevens, Denise R.; Flango, Vincent; Babcock, Lisa K.

    2016-01-01

    The Department of Veterans Affairs has an immediate problem at hand. Tens of thousands of employees are working in a high-stress work environment where fast-paced daily production requirements are critical. Employees are faced with a tremendous backlog of veterans' claims. Unfortunately, not only are the claims extremely complex, but there is…

  5. Continuous directed evolution of aminoacyl-tRNA synthetases

    PubMed Central

    Bryson, David I.; Fan, Chenguang; Guo, Li-Tao; Miller, Corwin; Söll, Dieter; Liu, David R.

    2017-01-01

    Directed evolution of orthogonal aminoacyl-tRNA synthetases (AARSs) enables site-specific installation of non-canonical amino acids (ncAAs) into proteins. Traditional evolution techniques typically produce AARSs with greatly reduced activity and selectivity compared to their wild-type counterparts. We designed phage-assisted continuous evolution (PACE) selections to rapidly produce highly active and selective orthogonal AARSs through hundreds of generations of evolution. PACE of a chimeric Methanosarcina spp. pyrrolysyl-tRNA synthetase (PylRS) improved its enzymatic efficiency (kcat/KMtRNA) 45-fold compared to the parent enzyme. Transplantation of the evolved mutations into other PylRS-derived synthetases improved yields of proteins containing non-canonical residues up to 9.7-fold. Simultaneous positive and negative selection PACE over 48 h greatly improved the selectivity of a promiscuous Methanocaldococcus jannaschii tyrosyl-tRNA synthetase variant for site-specific incorporation of p-iodo-L-phenylalanine. These findings offer new AARSs that increase the utility of orthogonal translation systems and establish the capability of PACE to efficiently evolve orthogonal AARSs with high activity and amino acid specificity. PMID:29035361

  6. Synthesis of Energetic Materials by Rapid Expansion of a Supercritical Solution into Aqueous Solution (RESS-AS) Process

    DTIC Science & Technology

    2010-12-02

    1366-1373, (2005). 16. Young, T . J ., Mawson , S., Johnston, K. P., Henriksen, I. B., Pace, G. W., and Mishra, A. K., Rapid Expansion from...Synthesis of Energetic Materials by Rapid Expansion of a Supercritical Solution into Aqueous Solution (RESS-AS) Process* J . T . Essel, A. C...Cortopassi, K. K. Kuo, J . H. Adair, and C. G. Leh The Pennsylvania State University University Park, PA 16802 USA T . M. Klapötke Ludwig Maximilian

  7. Market Mobilities/Immobilities: Mutation, Path-Dependency, and the Spread of Charter School Policies in the United States

    ERIC Educational Resources Information Center

    Cohen, Dan

    2017-01-01

    Over the past 25 years charter school policies have spread through the United States at a rapid pace. However, despite this rapid growth these policies have spread unevenly across the country with important variations in how charter school systems function in each state. Drawing on case studies in Michigan and Oregon, this article argues that…

  8. Influence of verapamil on tachycardia-induced alterations of PP1 and PP2A in rabbit atrium

    PubMed Central

    Laszlo, Roman; Winkler, Christoph; Wöhrl, Stefan; Laszlo, Sara; Eick, Christian; Schreieck, Jürgen; Bosch, Ralph F

    2007-01-01

    BACKGROUND Long-term atrial fibrillation changes in many regulatory and structural processes may result in stabilization of the arrhythmia. There is evidence that decreased amplitude of L-type Ca2+ current – probably a key mechanism of atrial remodelling –resulting from changes in expression of regulatory proteins is at least jointly responsible. OBJECTIVES To assess the expressions of protein phosphatases PP1 and PP2A, as well as the effect of verapamil pretreatment (VPT), in the early phases of atrial fibrillation in a rabbit model. METHODS Four groups, each consisting of six animals, were studied: ‘not paced, no drug’ group; ‘paced, no drug’ group (rapid atrial pacing [RAP] 600 beats/min for 24 h); ‘not paced, verapamil’ (NPV) group (duration of VPT was seven days, verapamil 7.5 mg/kg was administered every 12 h); and ‘paced, verapamil’ (PV) group (pacemaker stimulation after VPT). Protein expression was evaluated by Western blot analysis. RESULTS RAP resulted in an augmented (32%) PP1 expression (not paced, no drug group versus paced, no drug group). The increase in PP1 expression was prevented with VPT (NPV group versus PV group). Expression of PP2A was not influenced by RAP. However, VPT led to an increase of PP2A expression (16%) after RAP (NPV group versus PV group). CONCLUSIONS Fortified expression of protein phosphatases might be – besides transcriptional downregulation of channel subunits – another important cause of reduced L-type Ca2+ current after RAP. Blocking L-type Ca2+ channels with verapamil to prevent tachycardia-induced changes of PP1 expression might be expedient. PMID:18651001

  9. Maximizing the Prospects for Progress Against Cancer

    Cancer.gov

    The 2018 American Society of Clinical Oncology annual meeting featured numerous, potentially practice changing research findings, according to NCI Director Dr. Norman Sharpless. In this Cancer Currents post, Dr. Sharpless discusses the rapid pace of progress in cancer research.

  10. Advanced Traveler Information Systems (ATIS) 2.0 Precursor System: Final Report

    DOT National Transportation Integrated Search

    2018-03-01

    Advanced Traveler Information Systems (ATIS) have experienced significant growth since their initial inception in the 1990s. Technologies have continued to evolve at a rapid pace, enabling the integration of advanced solutions for traveler informatio...

  11. The Sixth Technological Revolution Shaping Today's High School Curriculum.

    ERIC Educational Resources Information Center

    Sion, Ronald T.

    1998-01-01

    The sixth technological revolution, electronic communications, challenges educators with the rapid pace of change, possible displacement of teachers, and the dangers of misapplication. Advantages include more active involvement of students in the learning process, flexibility, and variety. (SK)

  12. Encyclopedia Publishing: An Update

    ERIC Educational Resources Information Center

    Kister, Kenneth

    1978-01-01

    Problems discussed include difficulty of keeping pace with the "knowledge explosion" and rapidly changing social attitudes, higher production costs vs. declining sales, consumer dissatisfaction with sales tactics, and intellectual snobbery towards the product. Trends are the single volume edition, improved sales techniques, and publisher…

  13. COASTAL AND MARINE DATABASE SYSTEMS

    EPA Science Inventory

    Data miners trying to dig out new nuggets of insight from massive piles of rapidly expanding Web data; software bots skittering across the billion-page Web looking for specific information prey: Fast-paced developments in information technology make this an interesting time for c...

  14. Galaxy Feeds Off Gas Artist Concept

    NASA Image and Video Library

    2011-09-13

    In this artist conception based on data from ESA Herschel observatory, a galaxy accretes mass from rapid, narrow streams of cold gas. These filaments provide the galaxy with continuous flows of raw material to feed its star-forming at a leisurely pace

  15. The Background to Language Change in Hong Kong.

    ERIC Educational Resources Information Center

    Harrison, Godfrey; So, Lydia K. H.

    1996-01-01

    Seeks to link the rapid pace of societal change in Hong Kong over the past 50 years with changing patterns of language use there. Shows how the country has changed demographically, economically, politically, socially, and technologically. (16 references) (Author/CK)

  16. ITS strategic research plan, 2010-2014 : executive summary.

    DOT National Transportation Integrated Search

    2010-03-01

    Connectivity: Its a concept that is rapidly changing our daily habits: real-time information gives us the power to make decisions and act on opportunities, provides us with details needed to understand our fast-paced world, and brings us an awaren...

  17. Infrared heating

    USDA-ARS?s Scientific Manuscript database

    IR heating was first industrially used in the 1930s for automotive curing applications and rapidly became a widely applied technology in the manufacturing industry. Contrarily, a slower pace in the development of IR technologies for processing foods and agricultural products was observed, due to lim...

  18. Non-native plant invasion along elevation and canopy closure gradients in a Middle Rocky Mountain ecosystem

    Treesearch

    Joshua P. Averett; Bruce McCune; Catherine G. Parks; Bridgett J. Naylor; Tim DelCurto; Ricardo Mata-Gonz??lez; RunGuo Zang

    2016-01-01

    Mountain environments are currently among the ecosystems least invaded by non-native species; however, mountains are increasingly under threat of non-native plant invasion. The slow pace of exotic plant invasions in mountain ecosystems is likely due to a combination of low anthropogenic disturbances, low propagule supply, and extreme/steep environmental gradients. The...

  19. Transferring PACE Assessments Upon Home Sale

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    National Renewable Energy Laboratory; Coughlin, Jason; Fuller, Merrian

    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 upfrontmore » 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 of this is in Boulder County where the following statement is included in the ClimateSmart PACE program materials: 'Please Note: There is no legal requirement that the loan be paid off when you refinance or sell your home. However, this may be an item subject to negotiation with a future buyer and may also be a matter of negotiation with the mortgage lender.' Such candid disclosure for what might be a low risk event can be debated. However, a selling point of PACE programs is the transferability of the lien to the new homeowner. To the degree this benefit is questioned, PACE programs may end up looking more like home equity loan financing, with the associated debt repaid at closing, rather than property-based financing that remains with the improved home. While it is possible that upfront disclosure might negatively impact participation rates in PACE programs, it also will protect the integrity of a PACE program in later years if such situations come to pass. Ideally, this will become less of an issue over time as more homebuyers understand the positive economic and societal benefits of owning a home with clean energy features.« less

  20. Alterations in left ventricular diastolic function in conscious dogs with pacing-induced heart failure

    NASA Technical Reports Server (NTRS)

    Komamura, K.; Shannon, R. P.; Pasipoularides, A.; Ihara, T.; Lader, A. S.; Patrick, T. A.; Bishop, S. P.; Vatner, S. F.

    1992-01-01

    We investigated in conscious dogs (a) the effects of heart failure induced by chronic rapid ventricular pacing on the sequence of development of left ventricular (LV) diastolic versus systolic dysfunction and (b) whether the changes were load dependent or secondary to alterations in structure. LV systolic and diastolic dysfunction were evident within 24 h after initiation of pacing and occurred in parallel over 3 wk. LV systolic function was reduced at 3 wk, i.e., peak LV dP/dt fell by -1,327 +/- 105 mmHg/s and ejection fraction by -22 +/- 2%. LV diastolic dysfunction also progressed over 3 wk of pacing, i.e., tau increased by +14.0 +/- 2.8 ms and the myocardial stiffness constant by +6.5 +/- 1.4, whereas LV chamber stiffness did not change. These alterations were associated with increases in LV end-systolic (+28.6 +/- 5.7 g/cm2) and LV end-diastolic stresses (+40.4 +/- 5.3 g/cm2). When stresses and heart rate were matched at the same levels in the control and failure states, the increases in tau and myocardial stiffness were no longer observed, whereas LV systolic function remained depressed. There were no increases in connective tissue content in heart failure. Thus, pacing-induced heart failure in conscious dogs is characterized by major alterations in diastolic function which are reversible with normalization of increased loading condition.

  1. Self-paced cycling performance and recovery under a hot and highly humid environment after cooling.

    PubMed

    Gonzales, B R; Hagin, V; Guillot, R; Placet, V; Monnier-Benoit, P; Groslambert, A

    2014-02-01

    This study investigated the effects of pre- and post-cooling on self-paced time-trial cycling performance and recovery of cyclists exercising under a hot and highly humid environment (29.92 °C-78.52% RH). Ten male cyclists performed a self-paced 20-min time trial test (TT20) on a cyclo-ergometer while being cooled by a cooling vest and a refrigerating headband during the warm-up and the recovery period. Heart rate, power output, perceived exertion, thermal comfort, skin and rectal temperatures were recorded. Compared to control condition (222.78 ± 47 W), a significant increase (P<0.05) in the mean power output during the TT20 (239.07 ± 45 W; +7.31%) was recorded with a significant (P<0.05) decrease in skin temperature without affecting perceived exertion, heart rate, or rectal temperature at the end of the TT20. However, pace changes occurred independently of skin or rectal temperatures variations but a significant difference (P<0.05) in the body's heat storage was observed between both conditions. This result suggests that a central programmer using body's heat storage as an input may influence self-paced time-trial performance. During the recovery period, post-cooling significantly decreased heart rate, skin and rectal temperatures, and improved significantly (P<0.05) thermal comfort. Therefore, in hot and humid environments, wearing a cooling vest and a refrigerating headband during warm-up improves self-paced performance, and appears to be an effective mean of reaching skin rest temperatures more rapidly during recovery.

  2. Mind the model: effect of instrumentation on inducibility of atrial fibrillation in a sheep model.

    PubMed

    Willems, Rik; Holemans, Patricia; Ector, Hugo; Sipido, Karin R; Van de Werf, Frans; Heidbüchel, Hein

    2002-01-01

    Atrial electrical remodeling, shortening of the atrial effective refractory period (AERP) underlying atrial fibrillation (AF) has been described in different animal models. However, there remains some controversy regarding the time course of this electrical remodeling and the need for secondary factors in the development of AF. We investigated the effect of instrumentation on the inducibility of AF. We hypothesized that epicardial instrumentation could be a confounding factor that accelerates the development of AF. Thirty sheep were rapidly atrially paced at 600 beats/min for 15 weeks: 15 were endocardially instrumented and paced (endo), and 15 were both endocardially and epicardially instrumented. Six of these animals were endocardially paced (sham) and 9 were epicardially paced (epi). The underlying rhythm was determined at regular intervals, and electrophysiologic study was performed. AF developed significantly faster in the epi group. After 3 weeks of pacing, the cumulative incidence of sustained AF (>1 hour) already was 70% in this group versus only 14% and 20% in the endo and sham groups, respectively. After 15 weeks of pacing, this difference was no longer evident. Baseline AERP and minimal AERP, reached before the development of AF, were not significantly different in the three groups. Epicardial instrumentation (epi and sham) increased baseline left and right atrial pressures, but only epicardial stimulation (epi) led to early development of AF. In this sheep model of AF, the experimental setup is a major determinant of the inducibility of AF. Not epicardial instrumentation per se but epicardial stimulation accelerated the development of AF. Different animal models

  3. A Case of a Cardiac Resynchronization Therapy-Defibrillator Exhibiting a Lower and Alternately Variable Basic Rate.

    PubMed

    Iwazaki, Keigo; Kojima, Toshiya; Murasawa, Takahide; Yokota, Jun; Tanimoto, Hikaru; Matsuda, Jun; Fukuma, Nobuaki; Matsubara, Takumi; Shimizu, Yu; Oguri, Gaku; Hasumi, Eriko; Kubo, Hitoshi; Chang, Kyungho; Fujiu, Katsuhito; Komuro, Issei

    2018-05-30

    A cardiac resynchronization therapy defibrillator (CRT-D) (Medtronic Inc. Protecta XT) was implanted in a 67-year-old man who had cardiac sarcoidosis with extremely low cardiac function. He had ventricular tachycardia which was controlled by catheter ablation, medication and pacing. The programmed mode was DDI, lower rate was 90 beats/minute, paced AV delay was 150 ms, and the noncompetitive atrial pacing (NCAP) function was programmed as 300 ms.After his admission for pneumonia and heart failure, we changed his DDI mode to a DDD mode because he had atrial tachycardia, which led to inadequate bi-ventricular pacing. After a while, there were cycle lengths which were longer than his device setting and alternately varied. We were able to avoid this phenomenon with AV delay of 120 ms and NCAP of 200 ms.NCAP is an algorithm which creates a gap above a certain period after the detection of an atrial signal during the postventricular atrial refractory period of the pacemaker. This is to prevent atrial tachycardia and repetitive non-reentrant ventriculoatrial (VA) synchrony in the presence of retrograde VA conduction. But in this case, NCAP algorithm induced much lower rate than the programmed basic lower rate. This situation produced some arrhythmias and exacerbated symptoms of heart failure. This had to be paid attention to, especially when the device was programmed at high basic heart rate.

  4. A next generation advanced traveler information precursor system (ATIS 2.0 precursor system) concept of operations.

    DOT National Transportation Integrated Search

    2016-10-27

    Advanced Traveler Information Systems (ATIS) have experienced significant growth since its initial inception in the 1990s. Technologies have continued to evolve at a rapid pace, enabling the integration of advanced solutions for traveler information ...

  5. TRADING STORMWATER ABATEMENT CREDITS IN CINCINNATI'S SHEPHERD CREEK

    EPA Science Inventory

    The problem of stormwater runoff management grows apace with continued urbanization, yet the management tools for this growning non-profit source problem have not fully kept pace. The rapid growth of stormwater utilities around the nation is an important step toward providing an...

  6. A next generation advanced traveler information precursor system (ATIS 2.0 precursor system) system requirements.

    DOT National Transportation Integrated Search

    2016-12-01

    Advanced Traveler Information Systems (ATIS) have experienced significant growth since their initial inception in the 1990s. Technologies have continued to evolve at a rapid pace, enabling the integration of advanced solutions for traveler informatio...

  7. Occupant protection issues among older drivers and passengers. Volume 1, Final report

    DOT National Transportation Integrated Search

    2008-04-01

    With the older adult population of the United States growing at a rapid pace, the National Highway Traffic Safety Administration (NHTSA) is concerned with highway safety issues affecting this age group. NHTSA initiated a three-stage research study in...

  8. A next generation advanced traveler information precursor system (ATIS 2.0 precursor system) use cases report.

    DOT National Transportation Integrated Search

    2017-05-01

    Advanced Traveler Information Systems (ATIS) have experienced significant growth since their initial inception in the 1990s. Technologies have continued to evolve at a rapid pace, enabling the integration of advanced solutions for traveler informatio...

  9. An Evaluation of Ecotoxicity Test Guidelines: Their Adequacy for Nanomaterials

    EPA Science Inventory

    Advances in nanotechnology are resulting in the production of new nanomaterials at a rapid pace. Driving the dramatic development of new materials and products is the prospect of stronger and lighter materials, better and more efficient energy systems, potential tremendous benefi...

  10. Trained humans can exercise safely in extreme dry heat when drinking water ad libitum.

    PubMed

    Nolte, Heinrich W; Noakes, Timothy D; Van Vuuren, Bernard

    2011-09-01

    Guidelines to establish safe environmental exercise conditions are partly based on thermal prescriptive zones. Yet there are reports of self-paced human athletic performances in extreme heat. Eighteen participants undertook a 25-km route march in a dry bulb temperature reaching 44.3°C. The mean (± s) age of the participants was 26.0 ± 3.7 years. Their mean ad libitum water intake was 1264 ± 229 mL · h(-1). Predicted sweat rate was 1789 ± 267 mL · h(-1). Despite an average body mass loss of 2.73 ± 0.98 kg, plasma osmolality and serum sodium concentration did not change significantly during exercise. Total body water fell 1.47 kg during exercise. However, change in body mass did not accurately predict changes in total body water as a 1:1 ratio. There was a significant relationship (negative slope) between post-exercise serum sodium concentration and changes in both body mass and percent total body water. There was no relationship between percent body mass loss and peak exercise core temperature (39 ± 0.9°C) or exercise time. We conclude that participants maintained plasma osmolality, serum sodium concentration, and safe core temperatures by (1) adopting a pacing strategy, (2) high rates of ad libitum water intake, and (3) by a small reduction in total body water to maintain serum sodium concentration. Our findings support the hypothesis that humans are the mammals with the greatest capacity for exercising in extreme heat.

  11. Ventricular, but not atrial, M2-muscarinic receptors increase in the canine pacing-overdrive model of heart failure.

    PubMed

    Wilkinson, M; Giles, A; Armour, J A; Cardinal, R

    1996-01-01

    To investigate the effects of heart failure induced by chronic rapid ventricular pacing (six weeks) on canine atrial and ventricular muscarinic receptors. Dogs (n = 4) were fitted with a bipolar pacing electrode connected to a Medtronic pacemaker set at 240 stimuli/min. Pacing was maintained for six weeks. Tissue samples obtained from the left atrium and ventral wall of the left ventricle were frozen at -70 degrees C. Control tissue was obtained from normal dogs (n = 6) following anesthesia and thoracotomy. M2-muscarinic receptors were characterized and quantified in tissue micropunches using the hydrophilic ligand [3H] N-methyl-scopolamine (NMS). Cardiac tissue bound [3H] NMS with the specificity of an M2 subtype. Tachycardia-induced heart failure did not affect atrial muscarinic receptors but signify left ventricular myocytes (control 160.0 +/- 10.0 fmol/mg protein versus heart failure 245.0 +/- 25.0 fmol/mg protein; P < 0.01). Canine ventricular muscarinic receptors display a specificity for the M2 subtype. In contrast to previous work, tachycardia-induced heart failure was accompanied by an increase (+ 53%) in ventricular, but not atrial, M2 receptors compared with normal dogs.

  12. Pacing-induced palmar sweating evaluated by unique hygrometer: possible implications of sympathetic activation during tachycardia.

    PubMed

    Maruyama, T; Yanaga, T; Makino, N

    2000-03-01

    Although reflex sympathetic activation is a major determinant of the haemodynamic tolerability of ventricular tachycardia (VT), the methods for evaluating this aspect during on-going VT remain invasive and complicated. Palmar sweating as an indirect but non-invasive measure of sympathetic activity was estimated by means of a unique hygrometer under right ventricular (RV) rapid pacing (up to 150 beats min-1) replicating VT, and concurrent monitoring of aortic blood pressure in five patients with various kinds of cardiac arrhythmias in our electrophysiological laboratory. The peak palmar sweating rate in arbitrary units was augmented as the RV pacing rate increased and was proportional to the pacing-induced fall in systolic blood pressure (SBP), with a correlation coefficient of more than 0.903 (P<0.006). The slope of linearity between the sweating rate and the fall in SBP varied among individual patients, with greater sweating amplitude in the younger patients even with the same extent of fall in SBP. This preliminary study suggests sympathetic acceleration caused by haemodynamic deterioration under simulated VT, and therefore this protocol may be able to predict the haemodynamic tolerability of sustained monomorphic VT.

  13. A slow-releasing form of prostacyclin agonist (ONO1301SR) enhances endogenous secretion of multiple cardiotherapeutic cytokines and improves cardiac function in a rapid-pacing-induced model of canine heart failure.

    PubMed

    Shirasaka, Tomonori; Miyagawa, Shigeru; Fukushima, Satsuki; Saito, Atsuhiro; Shiozaki, Motoko; Kawaguchi, Naomasa; Matsuura, Nariaki; Nakatani, Satoshi; Sakai, Yoshiki; Daimon, Takashi; Okita, Yutaka; Sawa, Yoshiki

    2013-08-01

    Cardiac functional deterioration in dilated cardiomyopathy (DCM) is known to be reversed by intramyocardial up-regulation of multiple cardioprotective factors, whereas a prostacyclin analog, ONO1301, has been shown to paracrinally activate interstitial cells to release a variety of protective factors. We here hypothesized that intramyocardial delivery of a slow-releasing form of ONO1301 (ONO1301SR) might activate regional myocardium to up-regulate cardiotherapeutic factors, leading to regional and global functional recovery in DCM. ONO1301 elevated messenger RNA and protein level of hepatocyte growth factor, vascular endothelial growth factor, and stromal-derived factor-1 of normal human dermal fibroblasts in a dose-dependent manner in vitro. Intramyocardial delivery of ONO1301SR, which is ONO1301 mixed with polylactic and glycolic acid polymer (PLGA), but not that of PLGA only, yielded significant global functional recovery in a canine rapid pacing-induced DCM model, assessed by echocardiography and cardiac catheterization (n = 5 each). Importantly, speckle-tracking echocardiography unveiled significant regional functional recovery in the ONO1301-delivered territory, consistent to significantly increased vascular density, reduced interstitial collagen accumulation, attenuated myocyte hypertrophy, and reversed mitochondrial structure in the corresponding area. Intramyocardial delivery of ONO1301SR, which is a PLGA-coated slow-releasing form of ONO1301, up-regulated multiple cardiotherapeutic factors in the injected territory, leading to region-specific reverse left ventricular remodeling and consequently a global functional recovery in a rapid-pacing-induced canine DCM model, warranting a further preclinical study to optimize this novel drug-delivery system to treat DCM. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  14. Slow Adaptation in the Face of Rapid Warming Leads to the Collapse of Atlantic Cod in the Gulf of Maine

    NASA Astrophysics Data System (ADS)

    Pershing, A. J.; Alexander, M. A.; Hernandez, C.; Kerr, L. A.; Le Bris, A.; Mills, K.; Nye, J. A.; Record, N.; Scannell, H. A.; Scott, J. D.; Sherwood, G. D.; Thomas, A. C.

    2016-02-01

    Climate change is altering conditions in all marine ecosystems, but the pace of change is not uniform. Rapid changes in environmental conditions pose a challenge for resource management, especially when available tools or policies assume the environment is stationary. Between 2004 and 2013, the Gulf of Maine and northwest Atlantic Shelf warmed at a rate that few large marine ecosystems have ever experienced. This warming was associated with a northward shift in the Gulf Stream and with Atlantic Multidecadal Oscillation and Pacific Decadal Oscillation. The unprecedented warming led to reduced recruitment and enhanced mortality of Atlantic cod. Fisheries management has built-in feedbacks designed to reduce quotas as populations decline, but the management process could not keep pace with the rapid temperature-related changes in the Gulf of Maine cod stock. Future recovery of this fishery now depends on both sound management and favorable temperatures. The experience in the Gulf of Maine highlights the need to incorporate environmental factors into resource management and to build resiliency in coupled social-ecological systems. It also highlights a need for scientific and policy guidance for managing species threatened by future warming.

  15. Self-paced brain-computer interface control of ambulation in a virtual reality environment.

    PubMed

    Wang, Po T; King, Christine E; Chui, Luis A; Do, An H; Nenadic, Zoran

    2012-10-01

    Spinal cord injury (SCI) often leaves affected individuals unable to ambulate. Electroencephalogram (EEG) based brain-computer interface (BCI) controlled lower extremity prostheses may restore intuitive and able-body-like ambulation after SCI. To test its feasibility, the authors developed and tested a novel EEG-based, data-driven BCI system for intuitive and self-paced control of the ambulation of an avatar within a virtual reality environment (VRE). Eight able-bodied subjects and one with SCI underwent the following 10-min training session: subjects alternated between idling and walking kinaesthetic motor imageries (KMI) while their EEG were recorded and analysed to generate subject-specific decoding models. Subjects then performed a goal-oriented online task, repeated over five sessions, in which they utilized the KMI to control the linear ambulation of an avatar and make ten sequential stops at designated points within the VRE. The average offline training performance across subjects was 77.2 ± 11.0%, ranging from 64.3% (p = 0.001 76) to 94.5% (p = 6.26 × 10(-23)), with chance performance being 50%. The average online performance was 8.5 ± 1.1 (out of 10) successful stops and 303 ± 53 s completion time (perfect = 211 s). All subjects achieved performances significantly different than those of random walk (p < 0.05) in 44 of the 45 online sessions. By using a data-driven machine learning approach to decode users' KMI, this BCI-VRE system enabled intuitive and purposeful self-paced control of ambulation after only 10 minutes training. The ability to achieve such BCI control with minimal training indicates that the implementation of future BCI-lower extremity prosthesis systems may be feasible.

  16. Microelectrode array measurement of potassium ion channel remodeling on the field action potential duration in rapid atrial pacing rabbits model.

    PubMed

    Sun, Juan; Yan, Huang; Wugeti, Najina; Guo, Yujun; Zhang, Ling; Ma, Mei; Guo, Xingui; Jiao, Changan; Xu, Wenli; Li, Tianqi

    2015-01-01

    Atrial fibrillation (AF) arises from abnormalities in atrial structure and electrical activity. Microelectrode arrays (MEA) is a real-time, nondestructive measurement of the resting and action potential signal, from myocardial cells, to the peripheral circuit of electrophysiological activity. This study examined the field action potential duration (fAPD) of the right atrial appendage (RAA) by MEA in rapid atrial pacing (RAP) in the right atrium of rabbits. In addition, this study also investigated the effect of potassium ion channel blockers on fAPD. 40 New Zealand white rabbits of either sex were randomly divided into 3 groups: 1) the control, 2) potassium ion channel blocker (TEA, 4-Ap and BaCl2), and 3) amiodarone groups. The hearts were quickly removed and right atrial appendage sectioned (slice thickness 500 μm). Each slice was perfused with Tyrode's solution and continuously stimulated for 30 minutes. Sections from the control group were superfused with Tyrode's solution for 10 minutes, while the blocker groups and amiodarone were both treated with their respective compounds for 10 minutes each. The fAPD of RAA and action field action potential morphology were measured using MEA. In non-pace (control) groups, fAPD was 188.33 ± 18.29 ms after Tyrode's solution superfusion, and 173.91 ± 6.83 ms after RAP. In pace/potassium ion channel groups, TEA and BaCl2 superfusion prolonged atrial field action potential (fAPD) (control vs blocker: 176.67 ± 8.66 ms vs 196.11 ± 10.76 ms, 182.22 ± 12.87 ms vs 191.11 ± 13.09 ms with TEA and BaCl2 superfusion, respectively, P < 0.05). 4-AP superfusion significantly prolonged FAPD. In pace/amiodarone groups, 4-Ap superfusion extended fAPD. MEA was a sensitive and stable reporter for the measurement of the tissue action potential in animal heart slices. After superfusing potassium ion channel blockers, fAPD was prolonged. These results suggest that Ito, IKur and IK1 remodel and mediate RAP-induced atrial electrical remodeling. Amiodarone alter potassium ion channel activity (Ito, IKur, IK1 and IKs), shortening fAPD.

  17. Cultivating the Social, Emotional, and Inner Lives of Children and Teachers

    ERIC Educational Resources Information Center

    Lantieri, Linda

    2012-01-01

    Adults often feel the pressures of today's fast-paced world and think back longingly to a time when their daily lives were a lot less hectic. One third of the respondents in one study report that they are living with "extreme stress" and almost half feel that the level of stress in their lives has increased over the past five years. Children are…

  18. Functional genomics of physiological plasticity and local adaptation in killifish.

    PubMed

    Whitehead, Andrew; Galvez, Fernando; Zhang, Shujun; Williams, Larissa M; Oleksiak, Marjorie F

    2011-01-01

    Evolutionary solutions to the physiological challenges of life in highly variable habitats can span the continuum from evolution of a cosmopolitan plastic phenotype to the evolution of locally adapted phenotypes. Killifish (Fundulus sp.) have evolved both highly plastic and locally adapted phenotypes within different selective contexts, providing a comparative system in which to explore the genomic underpinnings of physiological plasticity and adaptive variation. Importantly, extensive variation exists among populations and species for tolerance to a variety of stressors, and we exploit this variation in comparative studies to yield insights into the genomic basis of evolved phenotypic variation. Notably, species of Fundulus occupy the continuum of osmotic habitats from freshwater to marine and populations within Fundulus heteroclitus span far greater variation in pollution tolerance than across all species of fish. Here, we explore how transcriptome regulation underpins extreme physiological plasticity on osmotic shock and how genomic and transcriptomic variation is associated with locally evolved pollution tolerance. We show that F. heteroclitus quickly acclimate to extreme osmotic shock by mounting a dramatic rapid transcriptomic response including an early crisis control phase followed by a tissue remodeling phase involving many regulatory pathways. We also show that convergent evolution of locally adapted pollution tolerance involves complex patterns of gene expression and genome sequence variation, which is confounded with body-weight dependence for some genes. Similarly, exploiting the natural phenotypic variation associated with other established and emerging model organisms is likely to greatly accelerate the pace of discovery of the genomic basis of phenotypic variation.

  19. Functional Genomics of Physiological Plasticity and Local Adaptation in Killifish

    PubMed Central

    Galvez, Fernando; Zhang, Shujun; Williams, Larissa M.; Oleksiak, Marjorie F.

    2011-01-01

    Evolutionary solutions to the physiological challenges of life in highly variable habitats can span the continuum from evolution of a cosmopolitan plastic phenotype to the evolution of locally adapted phenotypes. Killifish (Fundulus sp.) have evolved both highly plastic and locally adapted phenotypes within different selective contexts, providing a comparative system in which to explore the genomic underpinnings of physiological plasticity and adaptive variation. Importantly, extensive variation exists among populations and species for tolerance to a variety of stressors, and we exploit this variation in comparative studies to yield insights into the genomic basis of evolved phenotypic variation. Notably, species of Fundulus occupy the continuum of osmotic habitats from freshwater to marine and populations within Fundulus heteroclitus span far greater variation in pollution tolerance than across all species of fish. Here, we explore how transcriptome regulation underpins extreme physiological plasticity on osmotic shock and how genomic and transcriptomic variation is associated with locally evolved pollution tolerance. We show that F. heteroclitus quickly acclimate to extreme osmotic shock by mounting a dramatic rapid transcriptomic response including an early crisis control phase followed by a tissue remodeling phase involving many regulatory pathways. We also show that convergent evolution of locally adapted pollution tolerance involves complex patterns of gene expression and genome sequence variation, which is confounded with body-weight dependence for some genes. Similarly, exploiting the natural phenotypic variation associated with other established and emerging model organisms is likely to greatly accelerate the pace of discovery of the genomic basis of phenotypic variation. PMID:20581107

  20. Resolving Inadequacies of the Navy Industrial Fund Cost Accounting System to Enable Its Use in the RAMP SMP (Rapid Acquisition of Manufactured Parts Small Manufactured Parts) Facility

    DTIC Science & Technology

    1988-12-01

    maintenance, depreciation , rent, utilities, insurance, and taxes. 6 Historically, manufacturing activities have been labor intensive and man-paced...developed and produced which renders older equipment obsolete sooner. As a result, equipment must be replaced more frequently and depreciation is charged...McIlhattan, 1987). As previously mentioned, automated manufacturing activities incur greater amounts of depreciation expenses more rapidly than a

  1. Attribution of extreme events in the western US to human activities

    NASA Astrophysics Data System (ADS)

    Mera, R. J.

    2015-12-01

    A project to investigate the role of human activities on the changing nature of extreme events in the western US began as part of a CLIVAR-sponsored Postdocs Applying Climate Expertise (PACE) project. The climate institution was the Oregon State University and the application partner was the Oregon Department of Land Conservation and Development (DLCD). DLCD was interested in the changes in weather extremes in the Pacific Northwest, specifically extreme rainfall, flooding, and droughts. The project employs very large ensembles of regional model simulations through volunteer computing resources and allows for probabilistic event attribution (PEA), an important climate research technique. The model was found to have good representation of atmospheric rivers, a major source of extreme precipitation in the Pacific Northwest. The model domain also encompasses California and Nevada. One of the studies focused on attribution of extreme heat in relation to vulnerable populations in California's Central Valley, where heat waves have become progressively more severe due to increasing nighttime temperatures. Specifically, we found that that (1) simulations of the hottest summer days during the 2000s were twice as likely to occur using observed levels of greenhouse gases than in a counterfactual world without major human activities, (2) detrimental impacts of heat on public health-relevant variables, such as the number of days above 40°C, can be quantified and attributed to human activities using PEA, and (3) PEA can serve as a tool for addressing climate justice concerns of populations within developed nations. The research conducted through the PACE program has also provided a framework for a pioneering climate attribution study at the Union of Concerned Scientists (UCS). The UCS project takes advantage of new research that shows that nearly two-thirds of carbon pollution released into the atmosphere, reported as carbon dioxide equivalent with hundred-year global warming potentials, can be traced to carbon extracted from the Earth by a subset of producers of coal, oil, natural gas, and cement manufacturers. The approach for this study is to use superensembles of regional model simulations to explore the specific fractional attribution to emissions traceable to 90 major industrial carbon producers.

  2. Why Teaching Faculty Diversity (Still) Matters

    ERIC Educational Resources Information Center

    Poloma, Asabe W.

    2014-01-01

    Students in schools, colleges, and universities are rapidly becoming more diverse while the teaching workforce has failed to keep pace. The underrepresentation of minority teachers on school faculties persists despite efforts by successful national teacher recruitment programs, such as the Institute for Recruitment of Teachers, to redress this…

  3. ICT and Pedagogy: Opportunities Missed?

    ERIC Educational Resources Information Center

    Adams, Paul

    2011-01-01

    The pace of Information and Communications Technology (ICT) development necessitates radical and rapid change for education. Given the English prevalence for an economically determinist orientation for educational outcomes, it seems pertinent to ask how learning in relation to ICT is to be conceptualised. Accepting the view that education needs to…

  4. The Classroom as Global Media Center

    ERIC Educational Resources Information Center

    Nair, Prakash

    2007-01-01

    This article looks at ways in which schools buildings designed for today and tomorrow can provide superior environments for learning by keeping pace with rapidly evolving technologies that have redefined the educational landscape. Wireless classrooms, data projectors and wall-mounted plasma monitors are cited as in-classroom technologies of…

  5. Engineered Nanomaterial Ecological Effects Research within ORD's National Health and Environmental Effects Laboratory

    EPA Science Inventory

    Advances in nanotechnology are resulting in the production of new nanomaterials at a rapid pace. Driving the dramatic development of new materials and products is the prospect of stronger and lighter materials, better and more efficient energy systems, potential tremendous benefi...

  6. Modern Impressions

    ERIC Educational Resources Information Center

    Simkus, Joyce

    2010-01-01

    Claude Monet and the Impressionists were the forward thinkers and painters of their time. They used quick brushstrokes and a rapid pace to capture lively outdoor scenes. Inspired by the colors and shadows revealed by sunlight, the Impressionists typically worked outside, without many preliminary sketches or drafts. This was in direct contrast to…

  7. The Junior College in International Perspective.

    ERIC Educational Resources Information Center

    Hall, Budd L.

    The concept of the junior college is spreading rapidly throughout the world. Statistics show that educational development is positively correlated with economic development, yet educational systems often have not kept pace with technological, social, and economic developments since World War II. Junior colleges, with their flexibility of function,…

  8. Life history linked to immune investment in developing amphibians.

    PubMed

    Woodhams, Douglas C; Bell, Sara C; Bigler, Laurent; Caprioli, Richard M; Chaurand, Pierre; Lam, Brianna A; Reinert, Laura K; Stalder, Urs; Vazquez, Victoria M; Schliep, Klaus; Hertz, Andreas; Rollins-Smith, Louise A

    2016-01-01

    The broad diversity of amphibian developmental strategies has been shaped, in part, by pathogen pressure, yet trade-offs between the rate of larval development and immune investment remain poorly understood. The expression of antimicrobial peptides (AMPs) in skin secretions is a crucial defense against emerging amphibian pathogens and can also indirectly affect host defense by influencing the composition of skin microbiota. We examined the constitutive or induced expression of AMPs in 17 species at multiple life-history stages. We found that AMP defenses in tadpoles of species with short larval periods (fast pace of life) were reduced in comparison with species that overwinter as tadpoles and grow to a large size. A complete set of defensive peptides emerged soon after metamorphosis. These findings support the hypothesis that species with a slow pace of life invest energy in AMP production to resist potential pathogens encountered during the long larval period, whereas species with a fast pace of life trade this investment in defense for more rapid growth and development.

  9. Membrane currents underlying activity in frog sinus venosus

    PubMed Central

    Brown, Hilary F.; Giles, Wayne; Noble, Susan J.

    1977-01-01

    1. The spontaneous electrical activity of small strips of muscle from the sinus venosus region of the heart of Rana catesbeiana was investigated using the double sucrose gap technique. The voltage clamp was used to record the ionic currents underlying the pace-maker depolarization and the action potential. 2. The records of spontaneous electrical activity are very similar to those obtained from the sinus venosus using micro-electrodes. Moreover, the pace-maker activity is almost completely insensitive to tetrodotoxin (TTX) at 2·0 × 10-6 g/ml., which suggests that the pace-maker responses can be classified as primary, as opposed to follower pacing. 3. In response to short rectangular depolarizing voltage clamp pulses, only one inward current is activated. This current is almost completely insensitive to TTX but can be blocked by manganese ions. It appears, therefore, to be equivalent to the slow inward (Ca2+/Na+) current, Isi, of other cardiac tissues. The threshold for Isi is near to the maximum diastolic potential, indicating that it must be activated during the pace-maker depolarization. 4. Interruption of the normal pace-maker depolarization by rapid activation of the voltage clamp circuit reveals the time-dependent decay of outward current. This current reverses between -75 and -90 mV and, therefore, is probably carried mainly by potassium ions. 5. Outward current decay is not a simple exponential, and Hodgkin—Huxley analysis suggests that two distinct components of outward current may be present. One of these is activated in the potential range of the pace-maker depolarization and the other at more positive potentials. Both outward currents reach full, steady-state activation at about zero mV, i.e. within the `plateau' range of the sinus action potential. 6. These results are compared with other recently published voltage clamp data from the rabbit sino—atrial node. 7. A hypothesis for the generation of pace-maker activity is presented which involves (i) decay of outward current and (ii) activation of the slow inward current, Isi. PMID:303699

  10. Trace-Based Microanalytic Measurement of Self-Regulated Learning Processes

    ERIC Educational Resources Information Center

    Siadaty, Melody; Gaševic, Dragan; Hatala, Marek

    2016-01-01

    To keep pace with today's rapidly growing knowledge-driven society, productive self-regulation of one's learning processes are essential. We introduce and discuss a trace-based measurement protocol to measure the effects of scaffolding interventions on self-regulated learning (SRL) processes. It guides tracing of learners' actions in a learning…

  11. Science for All. Research Brief

    ERIC Educational Resources Information Center

    Walker, Karen

    2008-01-01

    Students need to be competent in science because of its impact on everyday decision-making, the rapid pace of change and the increasing interdependent global economy (Lawton, 2007; U.S. Department of Education, 2000; Lederman, 1998). According to the National Research Council, "Teachers of science should develop communities of science learners…

  12. An App for Every Psychological Problem: Vision for the Future

    ERIC Educational Resources Information Center

    Brown, Alicia M.

    2016-01-01

    Innovations in mobile technology are occurring at a rapid pace. Mobile phone software applications (apps) in particular have great potential within the field of mental health. Lack of organizational oversight and hesitancy from providers to utilize mobile technology has delayed technological advancement--consequently limiting the ability of the…

  13. Student Loans for Higher Education

    ERIC Educational Resources Information Center

    Simons, Charlene Wear

    2008-01-01

    Student loans are a rapidly growing $85 billion a year industry fueled by the substantial higher economic returns associated with a college education, increased demand from students and their parents, and grant and scholarship funds that have not kept pace with rising school tuition and fees. This report describes federally subsidized and…

  14. Assessing the Learning Culture and Performance of Educational Institutions

    ERIC Educational Resources Information Center

    Kumar, Naresh

    2005-01-01

    In today's fast-paced economy, Higher Learning Institutions (HLIs) are encountering tremendous challenges from the rapid advancement and expansion of new areas of knowledge. Advancement in information, communication, and technologies fundamentally alter the way teaching and learning occurs in colleges and universities. Thus, it is imperative for…

  15. Empowering Learners with Mobile Open-Access Learning Initiatives

    ERIC Educational Resources Information Center

    Mills, Michael, Ed.; Wake, Donna, Ed.

    2017-01-01

    Education has been progressing at a rapid pace ever since educators have been able to harness the power of mobile technology. Open-access learning techniques provide more students with the opportunity to engage in educational opportunities that may have been previously restricted. "Empowering Learners with Mobile Open-Access Learning…

  16. Internationalization of Canadian Higher Education: Discrepancies between Policies and International Student Experiences

    ERIC Educational Resources Information Center

    Guo, Yan; Guo, Shibao

    2017-01-01

    The internationalization of higher education in Canada is happening at a rapid pace. One manifestation of internationalization is the increasing enrolment of international students in Canadian institutions. There is little research on international undergraduate students' experiences from their own perspectives as they adapt to a new educational…

  17. Internationalisation of Higher Education: Integrating International Students into Canadian Academic Environment

    ERIC Educational Resources Information Center

    Guo, Shibao; Chase, Mackie

    2011-01-01

    Fuelled by globalisation, the internationalisation of higher education in Canada is happening at a rapid pace. One manifestation of internationalisation is the increasing enrolment of international graduate students in Canadian institutions. Many of these students face challenges and barriers in integrating into Canadian academic environments…

  18. Developing Professional Skills in Undergraduate Engineering Students through Cocurricular Involvement

    ERIC Educational Resources Information Center

    Fisher, Dara R.; Bagiati, Aikaterini; Sarma, Sanjay

    2017-01-01

    As nations have sought to keep pace with rapid technological innovation, governments have renewed their focus on science, technology, engineering, and mathematics (STEM) education, with emphasis on developing both technical and non-technical skills in STEM students. This article examines which engineering-relevant skills may be developed by…

  19. How to Survive the Next Five Years.

    PubMed

    Jackson, Rem

    2016-01-01

    The rapid pace of change in medical practice combined with increasingly heavy regulation has created a negative mindset for many practitioners. Although the future of medical practice is uncertain, there are fundamentals that, if understood, can ensure the success of private practitioners. These include efficient practice management and effective practice marketing.

  20. Want to Create Lasting Change? Listen First, Design Second

    ERIC Educational Resources Information Center

    Twal, Nader

    2018-01-01

    The educational landscape around standards, assessment, professional development, and funding is changing at a rapid pace. This article asks how can education institutions--and educators--respond with a balance of urgency and coherence? How can education institutions temper the need for risk-taking and innovation with the responsibility to deliver…

  1. Predictions for 2013

    ERIC Educational Resources Information Center

    Raths, David

    2012-01-01

    January brings many opportunities for change. The new year also allows district technology leaders and innovators to reflect on how the rapid pace of technological change is impacting what happens in their classrooms. Instructional technologies that were all the rage a year ago (netbooks) can be swept aside by this year's favorite (iPads).…

  2. The Characterization of Brain Behavior Relationships via Cognitive Neuroinformatic Approaches

    ERIC Educational Resources Information Center

    Kalar, Donald James, II

    2009-01-01

    The scope, breadth, and volume of data characterizing our current understanding of how the brain functions is growing at an increasingly rapid pace. What is more, theories are becoming increasing complex and nuanced, integrating knowledge from multiple previously independent sources of scientific inquiry. The research described within this…

  3. The intersection of plant breeding, human health, and nutritional security: Lessons learned and future perspectives

    USDA-ARS?s Scientific Manuscript database

    In recent years, concerns about global, sustainable, and nutritional security have gained substantial momentum propelled by rapid increases in global population and food insecurity. Historically, plant breeding has played a key role in improving crop yield to keep pace with the rising global populat...

  4. Bringing Out Eveyone's Best: Ten Psychological Tips for Academic Department Leaders.

    ERIC Educational Resources Information Center

    Chambliss, Catherine

    Promoting academic departmental productivity requires vision, passion, and sensitivity while coping with the rapid pace of change. This paper presents 10 proven strategies for managing some common challenges faced by academic department chairs: (1) building a sense of family purpose; (2) establishing mechanisms to assure accountability; (3)…

  5. Knowledge Sharing at Work: An Examination of Organizational Antecedents

    ERIC Educational Resources Information Center

    Behnke, Tricia M.

    2010-01-01

    With the rapid pace of today's knowledge-driven industries, organizations are turning to successful knowledge management initiatives to obtain sustainable competitive advantage. As a result, one facet of knowledge management, knowledge sharing at work, has received increased researcher and practitioner attention in the last decade. However, in the…

  6. Dealing with the Nightmare of "Sexting"

    ERIC Educational Resources Information Center

    Boucek, Sara G.

    2009-01-01

    The phenomenon of "sexting," or forwarding nude or seminude photographs of other students in schools via cell phone or other electronic media, is occurring with regularity. Administrators and boards of education struggle with disciplining students for such actions when policies and procedures have not kept pace with the rapid changes in…

  7. Successful Design of Learning Solutions Being Situation Aware

    ERIC Educational Resources Information Center

    Niemelä, Pia; Isomöttönen, Ville; Lipponen, Lasse

    2016-01-01

    Education is increasingly enhanced by technology, and at the same time, the rapid pace of technology innovation and growing demand of consumers introduces challenges for providers of technological learning solutions. This paper investigates Finnish small and medium size companies who either develop or deliver technological solutions for education.…

  8. Future Leaders' Views on Organizational Culture

    ERIC Educational Resources Information Center

    Maloney, Krisellen; Antelman, Kristin; Arlitsch, Kenning; Butler, John

    2010-01-01

    Research libraries will continue to be affected by rapid and transformative changes in information technology and the networked environment for the foreseeable future. The pace and direction of these changes will profoundly challenge libraries and their staffs to respond effectively. This paper presents the results of a survey that was designed to…

  9. Math 3013--Developmental Mathematics I and II. Course Outline.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    This document contains the course syllabus and 12 independent practice modules for an introductory college algebra course that requires some previous knowledge of algebra and the ability to work at a rapid pace. Topics include the basic operations with signed integers; fractions; decimals; literal expressions; algebraic fractions; radicals;…

  10. Teachers' Knowledge of Education Law

    ERIC Educational Resources Information Center

    Littleton, Mark

    2008-01-01

    The knowledge base of education-related law is growing at a rapid pace. The increase in federal and state statutes is rising commensurate with litigation that directs teachers on curricular, professional, and social matters. At the same time, numerous studies provide significant evidence that teachers lack an adequate level of knowledge of…

  11. The Virtual Professor: A New Model in Higher Education

    ERIC Educational Resources Information Center

    Valentine, Randall; Bennett, Robert

    2013-01-01

    Traditional colleges and universities face a unique challenge of increasing the scope of educational operations to accommodate the growing demand for online education. While online enrollments in higher education have grown at a rapid pace, faculty resources have remained stagnant at many institutions due to budget constraints and a sluggish…

  12. Making Schools Future-Proof

    ERIC Educational Resources Information Center

    Dessoff, Alan

    2011-01-01

    Under pressure to keep spending down but also keep pace with rapid technology changes, many districts are future-proofing their schools--trying to get the most out of tech spending by providing solutions they can use now and in the future without major, expensive infrastructure overhauls. In the Folsom Cordova (California) Unified School District,…

  13. Effect of pacing-induced myocardial ischemia on platelet activation and fibrin formation in the coronary circulation.

    PubMed

    Nichols, A B; Gold, K D; Marcella, J J; Cannon, P J; Owen, J

    1987-07-01

    The effect of pacing-induced myocardial ischemia on platelet activation and fibrin formation was investigated in seven patients with severe proximal lesions of the left anterior descending coronary artery to determine if acute ischemia activates the coagulation system. Fibrin formation was assessed from plasma levels of fibrinopeptide A. Platelet activation was assessed by levels of platelet factor 4, beta-thromboglobulin and thromboxane B2. Plasma levels were measured before, during and after acute myocardial ischemia induced by rapid atrial pacing. Blood samples were collected from the ascending aorta and from the great cardiac vein through heparin-bonded catheters. The occurrence of anterior myocardial ischemia was established by electrocardiography and by myocardial lactate extraction. No significant transmyocardial gradients in the levels of fibrinopeptide A, platelet factor 4, beta-thromboglobulin or thromboxane B2 were found at rest, during ischemia or in the recovery period, and levels in the great cardiac vein did not change in response to ischemia. These data indicate that pacing-induced myocardial ischemia does not result in release of fibrinopeptide A, platelet factor 4, beta-thromboglobulin or thromboxane B2 into the coronary circulation, and imply that acute ischemia does not induce platelet activation or fibrin formation in the coronary circulation.

  14. Innovation for integrated command environments

    NASA Astrophysics Data System (ADS)

    Perry, Amie A.; McKneely, Jennifer A.

    2000-11-01

    Command environments have rarely been able to easily accommodate rapid changes in technology and mission. Yet, command personnel, by their selection criteria, experience, and very nature, tend to be extremely adaptive and flexible, and able to learn new missions and address new challenges fairly easily. Instead, the hardware and software components of the systems do no provide the needed flexibility and scalability for command personnel. How do we solve this problem? In order to even dream of keeping pace with a rapidly changing world, we must begin to think differently about the command environment and its systems. What is the correct definition of the integrated command environment system? What types of tasks must be performed in this environment, and how might they change in the next five to twenty-five years? How should the command environment be developed, maintained, and evolved to provide needed flexibility and scalability? The issues and concepts to be considered as new Integrated Command/Control Environments (ICEs) are designed following a human-centered process. A futuristic model, the Dream Integrated Command Environment (DICE) will be described which demonstrates specific ICE innovations. The major paradigm shift required to be able to think differently about this problem is to center the DICE around the command personnel from its inception. Conference participants may not agree with every concept or idea presented, but will hopefully come away with a clear understanding that to radically improve future systems, designers must focus on the end users.

  15. Effects of ventricular rate and regularity on the velocity and magnitude of left atrial appendage flow in atrial fibrillation

    PubMed Central

    Obel, O A; Luddington, L; Maarouf, N; Aytemir, K; Ekwall, C; Malik, M; Camm, A J

    2005-01-01

    Objective: To prospectively determine whether ventricular rate and regularity are significant determinants of the velocity and magnitude of left atrial appendage (LAA) flow. Design and patients: 12 patients with atrial fibrillation (AF), high degree atrioventricular block, and indwelling permanent pacemakers were studied. Setting: Cardiology department of a tertiary referral centre. Interventions: Pacing was triggered by an external programmable transcutaneous device. Patients were paced at 60, 120, and 150 beats/min in both regular and irregular rhythm. LAA flow velocity and magnitude were assessed with transoesophageal Doppler echocardiography. Main outcome measures: Peak and mean LAA inflow and outflow velocity, and time-velocity interval (TVI) of LAA flow. Results: Increasing ventricular rate was associated with significantly lower peak inflow (p < 0.01), peak outflow (p < 0.05), mean inflow (p < 0.01), and mean outflow (p < 0.05) velocities and with a lower TVI of LAA filling and emptying velocities (p < 0.01). This effect was noted at rates of 60 beats/min compared with both 120 and 150 beats/min. At a pacing rate of 120 beats/min there was a significantly higher total TVI when pacing at a regular than at an irregular rhythm (40.16 (14.6) cm v 30.74 (10.9) cm, p < 0.05). Conclusions: In this study, LAA filling velocities in patients in AF were significantly influenced by paced ventricular rate and to a much lesser extent ventricular rhythm. These results suggest that rapid ventricular rates may predispose to stasis in the LAA in AF. PMID:15894771

  16. Inserting Agility in System Development

    DTIC Science & Technology

    2012-07-01

    Agile IT Acquisition, IT Box, Scrum Inserting Agility in System Development Matthew R. Kennedy and Lt Col Dan Ward, USAF With the fast-paced nature...1,700 individuals and 71 countries, found Scrum and eXtreme Programming to be the most widely followed method- ologies (VersionOne, 2007). Other...University http://www.dau.mil 259 Defense ARJ, July 2012, Vol. 19 No. 3 : 249–264 Scrum Scrum is a framework used for project management, which is

  17. Transfer of Learning: The Effects of Different Instruction Methods on Software Application Learning

    ERIC Educational Resources Information Center

    Larson, Mark E.

    2010-01-01

    Human Resource Departments (HRD), especially instructors, are challenged to keep pace with rapidly changing computer software applications and technology. The problem under investigation revealed after instruction of a software application if a particular method of instruction was a predictor of transfer of learning, when other risk factors were…

  18. Place-Making in Higher Education: Co-Creating Engagement and Knowledge Practices in the Networked Age

    ERIC Educational Resources Information Center

    Swist, Teresa; Kuswara, Andreas

    2016-01-01

    The pedagogical locations, functions and possibilities of higher education continuously unfold as mobile technologies, digital content and social practices intersect at a rapid pace. There is an urgent need to understand better how student learning is situated within this complex system and interrelates with broader sociotechnical knowledge…

  19. Online History-Keeping for Outreach and Community Development

    ERIC Educational Resources Information Center

    Huwe, Terence K.

    2010-01-01

    The rapidly evolving digital world inspires much use of nautical terminology: (1) navigation; (2) discovery; (3) the voyage; and (4) the new terrain at the end of the journey. Considering how quickly new technologies are arriving on smartphones, the nautical adventure is continuing at an increased pace. Innovations in basic library services follow…

  20. Challenges to Christian Higher Education at a Time of Increasing Emphasis on Research

    ERIC Educational Resources Information Center

    Hemmings, Brian; Hill, Doug

    2014-01-01

    In Australia, both Christian and non-Christian higher education institutions (HEIs) have experienced a rapidly changing external environment that is becoming more performance-driven, particularly in relation to faculty research. Academics working in Australian Christian HEIs often feel pressure to keep pace with their counterparts in non-Christian…

  1. Professional Interactions: Negotiation and Expression for Future Physicians and Healthcare Providers

    ERIC Educational Resources Information Center

    Pan, Andrew J.; Pan, Aaron J.; Leary, Kimberlyn R.

    2017-01-01

    The rapid pace of change in medicine requires doctors to be effective conflict mediators and negotiators in the clinical workplace, and a multitude of research connects strong physician-patient communication to improved patient outcomes. Disparities in such skills exist among medical students and professionals, and are neither taught nor evaluated…

  2. An Analysis of States' Policies Regarding Social Media Use in Education

    ERIC Educational Resources Information Center

    Miller, Janette K.

    2016-01-01

    This policy analysis project focused on states' policies regarding social media use in education. Currently, policies, practices and laws are not keeping pace with the rapidly changing nature of technology. As a result of the quick advancement of social media practices, the need exists for organic policies and practices within the educational…

  3. Education in China

    ERIC Educational Resources Information Center

    Fengzhen, Yang

    2002-01-01

    In the past 20 years, China's economy has been developing rapidly. Yet is China's education keeping up the same pace as its economic development? What is the current situation for China's education? With the advent of knowledge-based economy, how will education in China adjust itself in order to meet the growing demands of economy? This paper will…

  4. Developing a Global Perspective in/for Science Teacher Education: The Case of Pollination

    ERIC Educational Resources Information Center

    Reis, Giuliano

    2014-01-01

    Science educators at all levels continuously struggle to keep pace with the rapidly developing understanding of the causes and potential solutions to current environmental issues while also trying to enthuse a new generation of passionate and knowledgeable scientists. However, how can future science teachers make science education more attractive…

  5. Innovation Efforts in Education and School Administration: Views of Turkish School Administrators

    ERIC Educational Resources Information Center

    Akin, Ugur

    2016-01-01

    Problem Statement: In the current information era, nearly all organizations make efforts to make innovations in the fields of information, communication, technology, etc. Educational organizations are no exception to this trend. Moreover, it can be argued that educational institutions make a particular effort to rapidly keep pace with change. In…

  6. An efficient estimator to monitor rapidly changing forest conditions

    Treesearch

    Raymond L. Czaplewski; Michael T. Thompson; Gretchen G. Moisen

    2012-01-01

    Extensive expanses of forest often change at a slow pace. In this common situation, FIA produces informative estimates of current status with the Moving Average (MA) method and post-stratification with a remotely sensed map of forest-nonforest cover. However, MA "smoothes out" estimates over time, which confounds analyses of temporal trends; and post-...

  7. To Infinity and Beyond: Using a Narrative Approach to Identify Training Needs for Unknown and Dynamic Situations

    ERIC Educational Resources Information Center

    Dachner, Alison M.; Saxton, Brian M.; Noe, Raymond A.; Keeton, Kathryn E.

    2013-01-01

    Training effectiveness depends on conducting a thorough needs assessment. Traditional needs assessment methods are insufficient for today's business environment characterized by rapid pace, risk, and uncertainty. To overcome the deficiencies of traditional needs assessment methods, a narrative-based unstructured interview approach with subject…

  8. Better Jobs, Brighter Futures, a Stronger Washington. Washington's Community and Technical Colleges

    ERIC Educational Resources Information Center

    Washington State Board for Community and Technical Colleges, 2015

    2015-01-01

    The world is changing rapidly. With changes in technology, demographics, and workforce trends, Washington needs colleges to not only keep pace, but lead the way. Washington's 34 community and technical colleges answer that call. The community and technical colleges have proven uniquely positioned to adapt to, embrace, and ignite change. Community…

  9. Vertical Integration of System-on-Chip Concepts in the Digital Design Curriculum

    ERIC Educational Resources Information Center

    Tang, Ying; Head, L. M.; Ramachandran, R. P.; Chatman, L. M.

    2011-01-01

    The rapid evolution of System-on-Chip (SoC) challenges academic curricula to keep pace with multidisciplinary/interdisciplinary system thinking. This paper presents a curricular prototype that cuts across artificial course boundaries and provides a meaningful exploration of diverse facets of SoC design. Specifically, experimental contents of a…

  10. Persistence and Change in Social Media

    ERIC Educational Resources Information Center

    Hogan, Bernie; Quan-Haase, Anabel

    2010-01-01

    In "Star Trek," Scotty suggests that Transwarp beaming is "like trying to hit a bullet with a smaller bullet, whilst wearing a blindfold, riding a horse." The study of social media faces similar challenges because new tools are developed at a rapid pace and existing tools are constantly being updated with new features, policies, and applications.…

  11. Charter Operators Spell Out Barriers to "Scaling Up"

    ERIC Educational Resources Information Center

    Zehr, Mary Ann

    2011-01-01

    The pace at which the highest-performing charter-management organizations (CMOs) are "scaling up" is being determined largely by how rapidly they can develop and hire strong leaders and acquire physical space, and by the level of support they receive for growth from city or state policies, say leaders from some charter organizations…

  12. The Relationship between Transformational Leadership and Knowledge Workers' Self-Directed Learning Readiness

    ERIC Educational Resources Information Center

    Aparicio, Ricardo Antonio

    2013-01-01

    The rapid pace of change for knowledge workers competing globally necessitates ongoing continuous learning. Increasingly, knowledge workers will need to be ready--willing and able--to engage in self-directed learning. This makes it important to understand what factors in the work environment might be related to the self-directed learning…

  13. Issue-Oriented Science: Using Socioscientific Issues to Engage Biology Students

    ERIC Educational Resources Information Center

    Lenz, Laura; Willcox, Maia K.

    2012-01-01

    In today's global society, with science and technology advancing at a rapid pace, issues about biological topics are common. A typical standards-based high school or general college-level biology classroom naturally lends itself to teaching issue-oriented science. In an issue-oriented classroom, students analyze and discuss personal, societal, and…

  14. Adaptive Teaching for English Language Arts: Following the Pathway of Classroom Data in Preservice Teacher Inquiry

    ERIC Educational Resources Information Center

    Athanases, Steven Z.; Bennett, Lisa H.; Wahleithner, Juliet Michelsen

    2015-01-01

    Consensus exists that effective teaching includes capacity to adapt instruction to respond to student learning challenges as they arise. Adaptive teachers may keep pace with rapidly evolving youth literacies and students' increasing cultural and linguistic diversity. Teachers are challenged to critically examine pedagogy when some contexts expect…

  15. Elevating Adult Civic Science Literacy through a Renewed Citizen Science Paradigm

    ERIC Educational Resources Information Center

    Cronin, David P.; Messemer, Jonathan E.

    2013-01-01

    America's adult populace has failed to keep pace with the rapid inundation of science-centric knowledge affecting nearly every facet of personal, familial, and communal life. With three out of every four American adults considered scientifically illiterate, adult civic science literacy (CSL) has reached alarmingly low levels. The purpose of…

  16. New Languages and Landscapes of Higher Education

    ERIC Educational Resources Information Center

    Scott, Peter, Ed.; Gallacher, Jim, Ed.; Parry, Gareth, Ed.

    2017-01-01

    The landscapes of higher education have been changing rapidly, with enormous growths in participation rates in many countries across the world, and major developments and changes within institutions. But the languages that we need to conceptualise and understand these changes have not been keeping pace. The central argument in this book is that…

  17. Language Revitalization Processes and Prospects: Quichua in the Ecuadorian Andes.

    ERIC Educational Resources Information Center

    King, Kendall A.

    This paper examines efforts to reverse language shift in two indigenous communities in southern Ecuador. The ongoing decline and rapid pace of extinction of many of the world's languages have received increasing amounts of attention, but while processes of language loss and extinction have been extensively studied, relatively little work of…

  18. Rapid Acquisition but Slow Extinction of an Attentional Bias in Space

    ERIC Educational Resources Information Center

    Jiang, Yuhong V.; Swallow, Khena M.; Rosenbaum, Gail M.; Herzig, Chelsey

    2013-01-01

    Substantial research has focused on the allocation of spatial attention based on goals or perceptual salience. In everyday life, however, people also direct attention using their previous experience. Here we investigate the pace at which people incidentally learn to prioritize specific locations. Participants searched for a T among Ls in a visual…

  19. Beyond "It Was Good": Students' Post-Study Abroad Practices for Negotiating Meaning

    ERIC Educational Resources Information Center

    Kortegast, Carrie A.; Boisfontaine, M. Terral

    2015-01-01

    Student participation in short-term study abroad programs has increased at a rapid pace; however, little is known about students' post--study abroad practices regarding negotiating meaning of their experiences. The purpose of this study is to explore students' post-study abroad participation and reification of their experiences using the…

  20. Land-cover change in the Gulf Coastal Plains and Ozarks Landscape conservation Cooperative, 1973 to 2000

    USDA-ARS?s Scientific Manuscript database

    Land-use change and other human-caused effects on land cover and biophysical conditions have a pervasive yet variable influence across the national landscape. The contemporary human influence on conditions is occurring at a relatively rapid pace, even while conservation efforts strive to maintain ec...

  1. Changes in Information Processing with Aging: Implications for Teaching Motor Skills.

    ERIC Educational Resources Information Center

    Anshel, Mark H.

    Although there are marked individual differences in the effect of aging on learning and performing motor skills, there is agreement that humans process information less efficiently with advanced age. Significant decrements have been found specifically with motor tasks that are characterized as externally-paced, rapid, complex, and requiring rapid…

  2. Accuracy of a disability instrument to identify workers likely to develop upper extremity musculoskeletal disorders.

    PubMed

    Stover, Bert; Silverstein, Barbara; Wickizer, Thomas; Martin, Diane P; Kaufman, Joel

    2007-06-01

    Work related upper extremity musculoskeletal disorders (MSD) result in substantial disability, and expense. Identifying workers or jobs with high risk can trigger intervention before workers are injured or the condition worsens. We investigated a disability instrument, the QuickDASH, as a workplace screening tool to identify workers at high risk of developing upper extremity MSDs. Subjects included workers reporting recurring upper extremity MSD symptoms in the past 7 days (n = 559). The QuickDASH was reasonably accurate at baseline with sensitivity of 73% for MSD diagnosis, and 96% for symptom severity. Specificity was 56% for diagnosis, and 53% for symptom severity. At 1-year follow-up sensitivity and specificity for MSD diagnosis was 72% and 54%, respectively, as predicted by the baseline QuickDASH score. For symptom severity, sensitivity and specificity were 86% and 52%. An a priori target sensitivity of 70% and specificity of 50% was met by symptom severity, work pace and quality, and MSD diagnosis. The QuickDASH may be useful for identifying jobs or workers with increased risk for upper extremity MSDs. It may provide an efficient health surveillance screening tool useful for targeting early workplace intervention for prevention of upper extremity MSD problems.

  3. When dementia progresses quickly: a practical approach to the diagnosis and management of rapidly progressive dementia.

    PubMed

    Day, Gregory S; Tang-Wai, David F

    2014-01-01

    Making a diagnosis of rapidly progressive dementia requires practical adaptation of the skills used to assess patients with chronic causes of cognitive impairment. An expedited assessment, commensurate with the accelerated pace of the disease, is required to identify the cause of symptoms amidst a myriad of possibilities. Features upon history, physical examination and cognitive assessment that support specific diagnoses are reviewed, and a stratified approach to testing is presented. The use of readily-accessible investigations is prioritized, acknowledging the implications and applications of novel diagnostic tests. The coordinated use of clinical and laboratory measures are promoted as a means of facilitating rapid evaluation, with the ultimate goal of identifying patients with potentially reversible causes of rapidly progressive dementia.

  4. Health costs of reproduction are minimal despite high fertility, mortality and subsistence lifestyle.

    PubMed

    Gurven, Michael; Costa, Megan; Ben Trumble; Stieglitz, Jonathan; Beheim, Bret; Eid Rodriguez, Daniel; Hooper, Paul L; Kaplan, Hillard

    2016-07-20

    Women exhibit greater morbidity than men despite higher life expectancy. An evolutionary life history framework predicts that energy invested in reproduction trades-off against investments in maintenance and survival. Direct costs of reproduction may therefore contribute to higher morbidity, especially for women given their greater direct energetic contributions to reproduction. We explore multiple indicators of somatic condition among Tsimane forager-horticulturalist women (Total Fertility Rate = 9.1; n =  592 aged 15-44 years, n = 277 aged 45+). We test whether cumulative live births and the pace of reproduction are associated with nutritional status and immune function using longitudinal data spanning 10 years. Higher parity and faster reproductive pace are associated with lower nutritional status (indicated by weight, body mass index, body fat) in a cross-section, but longitudinal analyses show improvements in women's nutritional status with age. Biomarkers of immune function and anemia vary little with parity or pace of reproduction. Our findings demonstrate that even under energy-limited and infectious conditions, women are buffered from the potential depleting effects of rapid reproduction and compound offspring dependency characteristic of human life histories.

  5. Time course and degree of hyperinflation with metronome-paced tachypnea in COPD patients.

    PubMed

    Weigt, S Samuel; Abrazado, Marlon; Kleerup, Eric C; Tashkin, Donald P; Cooper, Christopher B

    2008-10-01

    In COPD patients, tachypnea should increase (dynamic) hyperinflation by shortening expiratory time. We developed a method to evaluate the time course and degree of dynamic hyperinflation during metronome-paced tachypnea. Fourteen patients with stable COPD (FEV(1) 43 +/- 13% predicted) were studied. Inspiratory capacity (IC) was measured breathing through a flow transducer. Subjects paced their respiratory rate (f(R)) at 20/min, 30/min and 40/min for 60-second periods in response to audible tones generated by a computer. IC measurements were obtained at baseline and after 30 and 60 seconds at each f(R). End-tidal carbon dioxide was monitored and f(R) was allowed to return to baseline between periods of tachypnea. Tachypnea produced reductions in IC of 200 +/- 240 ml, 380 +/- 330 ml and 540 +/- 300 ml after 30 seconds at 20/min, 30/min and 40/min, respectively. IC reduction at 60 seconds was similar to 30 seconds for each f(R). In patients with moderate-to-severe COPD, the dynamic hyperinflation induced by metronome-paced tachypnea was shown to occur rapidly and be complete by 30 seconds for a given f(R). Controlled increments in f(R) produced stepwise increases in dynamic hyperinflation. This standardized method could be a useful and easier method of assessing dynamic hyperinflation in COPD patients before and after therapeutic interventions.

  6. Ablation and pacing: improving brain perfusion and cognitive function in patients with atrial fibrillation and uncontrolled ventricular rates.

    PubMed

    Efimova, Irina; Efimova, Nataliya; Chernov, Vladimir; Popov, Sergey; Lishmanov, Yuri

    2012-03-01

    The aim of our study was to determine if ablation and pacing improved brain perfusion (BP) and cognitive function (CF) in patients with medically refractory rapidly conducted atrial fibrillation (Med Refr RCAF). The study included 17 patients with Med Refr RCAF (average age 55.3 ± 4.5 years). All patients underwent brain single photon emission computed tomography scanning with (99m) Tc-hexamethylpropylene amine oxime and comprehensive neuropsychological testing before and after 3 months following pacemaker implantation. The BP was significantly lower in all regions in patients with Med Refr RCAF compared with the control group. The greatest BP decrease was revealed in the inferior frontal (P = 0.002) and posterior parietal (P = 0.024) brain regions. These patients showed cognitive deficit in 94%. There was a direct correlation between BP and CF parameters. Ablation followed by pacemaker implantation had a positive effect on BP and CF in all patients with Med Refr RCAF. Thus, BP increased in the right inferior frontal (P = 0.01), in the left superior frontal (P = 0.007), and in the left temporal (P = 0.005) cortex. These patients demonstrated improvements in immediate and delayed verbal memory, immediate and delayed visual memory, abstract mentation, attention, psychomotor speed, as well as in learning. Patients with atrial fibrillation and rapid ventricular rates refractory to medical treatment have marked signs of brain hypoperfusion and impaired CF. Ablation and pacing improve left ventricular systolic function, thereby increasing BP and improving CF. ©2011, The Authors. Journal compilation ©2011 Wiley Periodicals, Inc.

  7. Intrinsic cardiac nervous system in tachycardia induced heart failure.

    PubMed

    Arora, Rakesh C; Cardinal, Rene; Smith, Frank M; Ardell, Jeffrey L; Dell'Italia, Louis J; Armour, J Andrew

    2003-11-01

    The purpose of this study was to test the hypothesis that early-stage heart failure differentially affects the intrinsic cardiac nervous system's capacity to regulate cardiac function. After 2 wk of rapid ventricular pacing in nine anesthetized canines, cardiac and right atrial neuronal function were evaluated in situ in response to enhanced cardiac sensory inputs, stimulation of extracardiac autonomic efferent neuronal inputs, and close coronary arterial administration of neurochemicals that included nicotine. Right atrial neuronal intracellular electrophysiological properties were then evaluated in vitro in response to synaptic activation and nicotine. Intrinsic cardiac nicotine-sensitive, neuronally induced cardiac responses were also evaluated in eight sham-operated, unpaced animals. Two weeks of rapid ventricular pacing reduced the cardiac index by 54%. Intrinsic cardiac neurons of paced hearts maintained their cardiac mechano- and chemosensory transduction properties in vivo. They also responded normally to sympathetic and parasympathetic preganglionic efferent neuronal inputs, as well as to locally administered alpha-or beta-adrenergic agonists or angiotensin II. The dose of nicotine needed to modify intrinsic cardiac neurons was 50 times greater in failure compared with normal preparations. That dose failed to alter monitored cardiovascular indexes in failing preparations. Phasic and accommodating neurons identified in vitro displayed altered intracellular membrane properties compared with control, including decreased membrane resistance, indicative of reduced excitability. Early-stage heart failure differentially affects the intrinsic cardiac nervous system's capacity to regulate cardiodynamics. While maintaining its capacity to transduce cardiac mechano- and chemosensory inputs, as well as inputs from extracardiac autonomic efferent neurons, intrinsic cardiac nicotine-sensitive, local-circuit neurons differentially remodel such that their capacity to influence cardiodynamics becomes obtunded.

  8. Beyond the extreme: Recovery dynamics following heat and drought stress in trees

    NASA Astrophysics Data System (ADS)

    Ruehr, N.; Duarte, A. G.; Arneth, A.

    2016-12-01

    Plant recovery processes following extreme events can have profound impacts on forest carbon and water cycling. However, large knowledge gaps persist on recovery dynamics of tree physiological processes following heat and drought stress. To date, few experimental studies exist that include recovery responses in stress research. We synthesized recent research on tree recovery processes related to carbon and water exchange following heat and drought stress, and show that the intensity of stress can affect the pace of recovery with large variations among tree species and processes. Following stress release, leaf water potential recovers instantaneously upon rewatering as found in most studies. Transpiration (T), stomatal conductance (gs) and photosynthesis (A) often lag behind, with lowest recovery following severe stress. Interestingly, the patterns in heat and drought stress recovery apparently differ. While A recovers generally more quickly than gs following drought, which increases water-use-efficiency, both gs and A tend to remain reduced following heat events. The pace of recovery following heat events likely depends on water availability during stress and temperature maxima reached (photosynthetic impairment at temperatures > 40°C). Slow recovery during the initial post-stress days might result from hydraulic limitation and elevated levels of abscisic acid. The mechanisms resulting in a continued impairment of T and gs during a later stage of the recovery period (from weeks up to months) are still elusive. Feedback loops from the photosynthetic machinery, reduced mesophyll conductance or leaf morphological changes may play an important role. In summary, post-stress recovery can substantially affect tree carbon and water cycling. Thus, in order to estimate the impacts of extreme climate events on forest ecosystems in the long-term, we need a better understanding of recovery dynamics and their limitations in terms of stress timing, intensity and duration.

  9. Climate change adaptation and mitigation options a guide for natural resource managers in southern forest ecosystems

    Treesearch

    James M. Vose; Kier D. Klepzig

    2014-01-01

    The rapid pace of climate change and its direct and indirect effects on forest ecosystems present a pressing need for better scientific understanding and the development of new science-management partnerships. Understanding the effects of stressors and disturbances (including climatic variability), and developing and testing science-based management options to deal...

  10. Bureaucratic Activism and Radical School Change in Tamil Nadu, India

    ERIC Educational Resources Information Center

    Niesz, Tricia; Krishnamurthy, Ramchandar

    2013-01-01

    In 2007, Activity Based Learning (ABL), a child-centered, activity-based method of pedagogical practice, transformed classrooms in all of the over 37,000 primary-level government schools in Tamil Nadu, India. The large scale, rapid pace, and radical nature of educational change sets the ABL initiative apart from most school reform efforts.…

  11. Adjusting to the Growing Impact of Latinos on Indiana Public Schools

    ERIC Educational Resources Information Center

    Strietelmeier, Curtiss A.

    2010-01-01

    Over the last 15 years, the Latino population has expanded at a rapid pace in the United States. This national trend has been mirrored in Indiana. As a result, school districts within the state have developed structures and supports for the growing number of Latino students arriving in their schools. This study highlights some programs developed…

  12. The Relationship between Digital Leadership and Digital Implementation in Elementary Schools

    ERIC Educational Resources Information Center

    Domeny, Jami V.

    2017-01-01

    New technological advances are changing the landscape for both teaching and learning at a rapid pace. With an increase in the focus and allocation of funding on technology, schools need leaders who can facilitate the change process and support a digital learning culture for technology integration. As with any focus and initiative in education, the…

  13. REPORT ON THE PANEL SESSION: EMERGING ELECTRONICS ISSUES - HOW CAN WE MINIMIZE THE HEALTH AND ENVIRONMENTAL IMPACTS OF ELECTRONICS RECYCLING?

    EPA Science Inventory

    The production and use of electronic products is growing and the rapid pace at which the technology advances means that many electronic products become obsolete in a relatively short period of time. These factors are contributing to a growing challenge for waste management becaus...

  14. U.S. Public Libraries and the Use of Web Technologies, 2010. A Closer Look

    ERIC Educational Resources Information Center

    Lietzau, Zeth; Helgren, Jamie

    2011-01-01

    It's well known that technology is changing at an increasingly rapid pace and that many public libraries throughout the United States are attempting to adopt new technologies to better reach their patrons. In trade journals, blogs, and at library conferences, professionals in the field have continually discussed the best methods for using web…

  15. What Changes Can We Expect? Future Trends Impacting Early Childhood Education

    ERIC Educational Resources Information Center

    Neugebauer, Roger; Donohue, Chip; Schweinhart, Larry; Milic, Sasa; Martin, Jody

    2011-01-01

    The author invited some of his friends to give their views regarding key trends that will impact the early childhood world in the coming years. Chip Donohue, Director of Distance Learning, Erikson Institute, Chicago, Illinois, observed that the rapid pace of technology development and deployment has already changed, and will continue to change,…

  16. Making "Good" Choices: The Impact of Entitlement Models on Upskilling Later in Life. Research Report

    ERIC Educational Resources Information Center

    Polidano, Cain; van de Ven, Justin; Voitchovsky, Sarah

    2017-01-01

    Tailoring education policy to deliver the skills needed by modern labour markets is complicated by the rapid pace of technological change. These complications are amplified when the associated risks of technological redundancy and the lengthening working lifetimes are taken into account. At the heart of the challenge for policy-makers is…

  17. A Small-Wins Perspective: Educators Have a Role to Play in Narrowing the Generation Divide

    ERIC Educational Resources Information Center

    Nichols, Sharon L.; Good, Thomas L.

    2005-01-01

    Adults widely misunderstand youth. Although this is not a new phenomenon--adults have been baffled by teenagers for centuries--a rapidly changing media environment coupled with the increasing demands placed on the youth have fueled the growing generation divide in unprecedented ways. Indeed the modern, fast-paced, multi-tasked, highly mobile,…

  18. Interactive effects of disturbance and nitrogen availability on phosphorus dynamics of southern Appalachian forests

    Treesearch

    Corinne E. Block; Jennifer D. Knoepp; Jennifer M. Fraterrigo

    2013-01-01

    Understanding the main and interactive effects of chronically altered resource availability and disturbance on phosphorus (P) availability is increasingly important in light of the rapid pace at which human activities are altering these processes and potentially introducing P limitation. We measured P pools and fluxes in eighteen mixed forest stands at three elevations...

  19. Student Development and Experimental-Gestalt Therapy.

    ERIC Educational Resources Information Center

    Witchel, Robert

    The rapid pace at which societal changes have occurred in our culture has presented a tremendous challenge to higher education. A major attempt to meet this challenge has been the Tomorrow's Higher Education (THE) Project. The goal of the THE Project is to reconceptualize student affaris work in a way that will provide a measure of creative input…

  20. Energy Drinks: Topical Domain in the Emerging Literature and Neglected Areas of Research

    ERIC Educational Resources Information Center

    Piotrowski, Chris

    2014-01-01

    Prevalence statistics indicate that consumption of Energy drinks (EDs), often in combination with alcohol, is quite popular in the younger generation and particularly with college students. As literature on this topic is advancing at a rapid pace, it seemed instructive to examine which topics are emphasized in emerging EDs research. To that end, a…

  1. Lifelong Learning Imperative in Engineering: Summary of a Workshop

    ERIC Educational Resources Information Center

    Dutta, Debasish

    2010-01-01

    The 21st century is witnessing a rapid increase in the pace of knowledge creation in the sciences and engineering. Competing in this global economy requires a science and engineering workforce that is consistently at the technological forefront. Dr. Charles Vest, President of the National Academy of Engineering, in a speech at the University of…

  2. Just-in-Time Teaching in Statistics Classrooms

    ERIC Educational Resources Information Center

    McGee, Monnie; Stokes, Lynne; Nadolsky, Pavel

    2016-01-01

    Much has been made of the flipped classroom as an approach to teaching, and its effect on student learning. The volume of material showing that the flipped classroom technique helps students better learn and better retain material is increasing at a rapid pace. Coupled with this technique is active learning in the classroom. There are many ways of…

  3. From CATs to WILD HOGs: Elevating the Level of Discussion in the Online Classroom

    ERIC Educational Resources Information Center

    DeCosta, Meredith; Bergquist, Emily; Holbeck, Rick

    2015-01-01

    Online education is growing at a rapid pace. To meet the increasing demand for online education, many universities have designed courses to enable the instructor to be more of a facilitator than an active participant in the classroom space (Ragan, 2009). However, building an active, student-centered learning environment in online classrooms is…

  4. Global Report on Adult Learning and Education

    ERIC Educational Resources Information Center

    Chisholm, Lynne, Ed.; Hasan, Abrar, Ed.

    2010-01-01

    In the 21st century, the rapid pace and complexity of economic, technological and cultural changes require women and men to adapt and re-adapt throughout their lives--all the more so in the context of globalisation. In this era of the knowledge society--where production structure is shifting towards greater knowledge use and away from reliance on…

  5. The Assessment of Self-Directed Learning Readiness in Medical Education

    ERIC Educational Resources Information Center

    Monroe, Katherine Swint

    2014-01-01

    The rapid pace of scientific discovery has catalyzed the need for medical students to be able to find and assess new information. The knowledge required for physicians' skillful practice will change of the course of their careers, and, to keep up, they must be able to recognized their deficiencies, search for new knowledge, and critically evaluate…

  6. E-Service Quality in Higher Education and Frequency of Use of the Service

    ERIC Educational Resources Information Center

    Kim-Soon, Ng; Rahman, Abd; Ahmed, Muhudin

    2014-01-01

    Universities have been at the forefront of online service provision. Regular evaluations and appraisals of its e-services provided to students are regularly improvised to keep pace with the rapid changes of learning technology and competitiveness of its services provided. There is a dread of research works investigating e-service quality…

  7. Language Development of Children Born Following Intracytoplasmic Sperm Injection (ICSI) Combined with Assisted Oocyte Activation (AOA)

    ERIC Educational Resources Information Center

    D'haeseleer, Evelien; Vanden Meerschaut, Frauke; Bettens, Kim; Luyten, Anke; Gysels, Hannelore; Thienpont, Ylenia; De Witte, Griet; Heindryckx, Björn; Oostra, Ann; Roeyers, Herbert; De Sutter, Petra; van Lierde, Kristiane

    2014-01-01

    Background: The effect of assisted reproduction technology (ART) on language development is still unclear. Moreover, different techniques are introduced at rapid pace and are not always accompanied by extensive follow-up programmes. Aims: To investigate the language development of 3-10-year-old children born following ART using intracytoplasmic…

  8. 2009 Strategic Plan for Autism Spectrum Disorder Research. NIH Publication No. 09-7465

    ERIC Educational Resources Information Center

    Interagency Autism Coordinating Committee, 2009

    2009-01-01

    In response to the heightened societal concern over autism spectrum disorder (ASD), Congress passed the Combating Autism Act (CAA) of 2006 (P.L. 109-416). Through this Act, Congress intended to rapidly increase, accelerate the pace and improve coordination of scientific discovery in ASD research. The CAA requires the Interagency Autism…

  9. Secrets of Science. Videos 1-13. [Videotape.

    ERIC Educational Resources Information Center

    Walt Disney Publishing Group, Burbank, CA. Discover Magazine.

    Discoveries in science and technology are being made at such a rapid pace that it is often difficult for many teachers to stay abreast of new and relevant information. To assist teachers in keeping their students well informed of new discoveries in science, Discover Magazine developed a 13-part video series entitled "Secrets of Science." In each…

  10. Who Is Not Sleeping with Whom? What's Not Being Talked about in HRD?

    ERIC Educational Resources Information Center

    Trehan, Kiran

    2004-01-01

    Human resource development (HRD) occupies some interesting educational territory. Given the rapid pace of development and innovation in education and in the practice of HRD, coupled with alternative approaches to learning, a re-evaluation of HRD might be expected to be a prominent feature within discussions of the future practice of HRD. However,…

  11. Social Stratification and Higher Education Outcomes: The Case of Filipinos in Hawai`i

    ERIC Educational Resources Information Center

    Libarios, Ernest Niki D., Jr.

    2013-01-01

    Filipinos are the second largest ethnic group in Hawai'i and their population continues to grow at a rapid pace. However, they are among the lower socioeconomic groups in Hawai'i and are disproportionately represented in the University of Hawai'i system--overrepresented in the community colleges while underrepresented at the flagship campus, the…

  12. An Analysis of CPA Firm Recruiters' Perceptions of Online Masters of Accounting Degrees

    ERIC Educational Resources Information Center

    Metrejean, Eddie; Noland, Thomas G.

    2011-01-01

    Online education continues to grow at a rapid pace. Assessment of the effectiveness of online programs is needed to differentiate legitimate programs from diploma mills. The authors examined the perceptions of CPA firm recruiters on whether an online Master of Accounting (MACC) matters in the hiring decision. Results show that recruiters do not…

  13. Application of Universal Design for Learning in Corporate Technical Training Design: A Quantitative Study

    ERIC Educational Resources Information Center

    Irbe, Aina G.

    2016-01-01

    With the rise of a globalized economy and an overall increase in online learning, corporate organizations have increased training through the online environment at a rapid pace. Providing effective training the employee can immediately apply to the job has driven a need to improve online training programs. Numerous studies have identified that the…

  14. The Real Science Crisis: Bleak Prospects for Young Researchers

    ERIC Educational Resources Information Center

    Monastersky, Richard

    2007-01-01

    It is the best of times and worst of times to start a science career in the United States. Researchers today have access to powerful new tools and techniques--such as rapid gene sequencers and giant telescopes--that have accelerated the pace of discovery beyond the imagination of previous generations. But for many of today's graduate students, the…

  15. A Systematic Review Approach to Technologies Used for Learning and Education

    ERIC Educational Resources Information Center

    Purarjomandlangrudi, Afrooz; Chen, David; Nguyen, Anne

    2015-01-01

    E-learning is implementation of technologies in learning process and is growing at a very rapid pace. E-learning technology has matured noticeably and the majority of organisations are taking advantage of it in their educational systems. However, there is a lack of methodical and consistent paradigm of these technologies in literature. The purpose…

  16. Graphic Design for the Computer Age; Visual Communication for all Media.

    ERIC Educational Resources Information Center

    Hamilton, Edward A.

    Because of the rapid pace of today's world, graphic designs which communicate at a glance are needed in all information areas. The essays in this book deal with various aspects of graphic design. These brief essays, each illustrated with graphics, concern the following topics: a short history of visual communication, information design, the merits…

  17. Teaching Thinking Skills with Picture Books, K-3

    ERIC Educational Resources Information Center

    Polette, Nancy

    2007-01-01

    Many of the most talented authors and artists of the past and present have shared their thoughts and their gifts with young children through picture books. Many picture books allow young children to explore important ideas and to stretch their minds far beyond rote memorization. Young children absorb knowledge at a very rapid pace. In an age of…

  18. Cultural diversification promotes rapid phenotypic evolution in Xavánte Indians

    PubMed Central

    Hünemeier, Tábita; Gómez-Valdés, Jorge; Ballesteros-Romero, Mónica; de Azevedo, Soledad; Martínez-Abadías, Neus; Esparza, Mireia; Sjøvold, Torstein; Bonatto, Sandro L.; Salzano, Francisco Mauro; Bortolini, Maria Cátira; González-José, Rolando

    2012-01-01

    Shifts in social structure and cultural practices can potentially promote unusual combinations of allele frequencies that drive the evolution of genetic and phenotypic novelties during human evolution. These cultural practices act in combination with geographical and linguistic barriers and can promote faster evolutionary changes shaped by gene–culture interactions. However, specific cases indicative of this interaction are scarce. Here we show that quantitative genetic parameters obtained from cephalometric data taken on 1,203 individuals analyzed in combination with genetic, climatic, social, and life-history data belonging to six South Amerindian populations are compatible with a scenario of rapid genetic and phenotypic evolution, probably mediated by cultural shifts. We found that the Xavánte experienced a remarkable pace of evolution: the rate of morphological change is far greater than expected for its time of split from their sister group, the Kayapó, which occurred around 1,500 y ago. We also suggest that this rapid differentiation was possible because of strong social-organization differences. Our results demonstrate how human groups deriving from a recent common ancestor can experience variable paces of phenotypic divergence, probably as a response to different cultural or social determinants. We suggest that assembling composite databases involving cultural and biological data will be of key importance to unravel cases of evolution modulated by the cultural environment. PMID:22184238

  19. Plasma Metabolomics Biosignature According to HIV Stage of Infection, Pace of Disease Progression, Viremia Level and Immunological Response to Treatment.

    PubMed

    Scarpellini, Bruno; Zanoni, Michelle; Sucupira, Maria Cecilia Araripe; Truong, Hong-Ha M; Janini, Luiz Mario Ramos; Segurado, Ismael Dale Cotrin; Diaz, Ricardo Sobhie

    2016-01-01

    We evaluated plasma samples HIV-infected individuals with different phenotypic profile among five HIV-infected elite controllers and five rapid progressors after recent HIV infection and one year later and from 10 individuals subjected to antiretroviral therapy, five of whom were immunological non-responders (INR), before and after one year of antiretroviral treatment compared to 175 samples from HIV-negative patients. A targeted quantitative tandem mass spectrometry metabolomics approach was used in order to determine plasma metabolomics biosignature that may relate to HIV infection, pace of HIV disease progression, and immunological response to treatment. Twenty-five unique metabolites were identified, including five metabolites that could distinguish rapid progressors and INRs at baseline. Severe deregulation in acylcarnitine and sphingomyelin metabolism compatible with mitochondrial deficiencies was observed. β-oxidation and sphingosine-1-phosphate-phosphatase-1 activity were down-regulated, whereas acyl-alkyl-containing phosphatidylcholines and alkylglyceronephosphate synthase levels were elevated in INRs. Evidence that elite controllers harbor an inborn error of metabolism (late-onset multiple acyl-coenzyme A dehydrogenase deficiency [MADD]) was detected. Blood-based markers from metabolomics show a very high accuracy of discriminating HIV infection between varieties of controls and have the ability to predict rapid disease progression or poor antiretroviral immunological response. These metabolites can be used as biomarkers of HIV natural evolution or treatment response and provide insight into the mechanisms of the disease.

  20. The curse of wealth – Middle Eastern countries need to address the rapidly rising burden of diabetes

    PubMed Central

    Klautzer, Lisa; Becker, Joachim; Mattke, Soeren

    2014-01-01

    The energy boom of the last decade has led to rapidly increasing wealth in the Middle East, particularly in the oil and gas-rich Gulf Cooperation Council (GCC) countries. This exceptional growth in prosperity has brought with it rapid changes in lifestyles that have resulted in a significant rise in chronic disease. In particular the number of people diagnosed with diabetes has increased dramatically and health system capacity has not kept pace. In this article, we summarize the current literature to illustrate the magnitude of the problem, its causes and its impact on health and point to options how to address it. PMID:24757686

  1. Mochras Revisited: a new global standard for 25 million years of Jurassic Earth history - A drilling proposal for the International Continental Drilling Programme

    NASA Astrophysics Data System (ADS)

    Hesselbo, Stephen; Bjerrum, Christian; Hinnov, Linda; Mac Niocaill, Conall; Miller, Kenneth; Riding, James; van de Schootbrugge, Bas; Wonik, Thomas

    2014-05-01

    The Early Jurassic Epoch (201.4 - 175 Ma) was a time of extreme environmental change. Through this period there are well-documented examples of rapid transitions from cold, or even glacial climates, through to super-greenhouse events, the latter characterized worldwide by hugely enhanced organic carbon burial, multiple large-magnitude isotopic anomalies, global sea-level changes, and mass extinctions. These events not only reflect changes in the global climate system but are also thought to have had significant influence on the evolution of Jurassic marine and terrestrial biota. Furthermore, the events may serve as analogues for present-day and future environmental transitions. Although our knowledge of specific global change events within the Early Jurassic is rapidly improving, a prime case-in-point being the Toarcian Oceanic Anoxic Event (or T-OAE), we have neither documented all the events, nor do we have a comprehensive understanding of their timing, pacing, or triggers. A key factor contributing to our fragmentary knowledge is the scattered and discontinuous nature of the existing datasets. The major goal for this proposed ICDP project is therefore to produce a new global standard for these key 25 million years of Earth history by re-drilling a 45 year old borehole at Mochras Farm on the edge of Cardigan Bay, Wales, and to develop an integrated stratigraphy for the cored material, as well as high-resolution proxy-records of environmental change. The new datasets will be applied to understand fundamental questions about the long- and short-term evolution of the Earth System.

  2. Comparison of limb kinematics between collected and lengthened (medium/extended) trot in two groups of dressage horses on two different surfaces.

    PubMed

    Walker, V A; Tranquille, C A; Newton, J R; Dyson, S J; Brandham, J; Northrop, A J; Murray, R C

    2017-09-01

    Dressage horses are often asked to work in lengthened paces during training and competition, but to date there is limited information about the biomechanics of dressage-specific paces. Preliminary work has shown increased fetlock extension in extended compared with collected paces, but further investigation of the kinematic differences between collected, medium and extended trot in dressage horses is warranted. Investigation of the effect of collected vs. medium/extended trot on limb kinematics of dressage horses. Prospective kinematic evaluation. Twenty clinically sound horses in active dressage training were used. Group 1: Ten young horses (≤6 years) were assessed at collected and medium trot and Group 2: Ten mature horses (≥9 years) were assessed at collected and extended trot. All horses were evaluated on two different surfaces. High speed motion capture (240 Hz) was used to determine kinematic variables. Fore- and hindlimb angles were measured at mid-stance. Descriptive statistics and mixed effect multilevel regression analyses were performed. Speed and stride length were reduced and stride duration increased at collected compared with medium/extended trot. Lengthened trot (medium/extended trot) was associated with increased fetlock extension in both the fore- and hindlimbs in both groups of horses. Changes were greater in mature horses compared with young horses. Shoulder and carpus angles were associated with forelimb fetlock angle. Hock angle was not significantly influenced by pace. Surface had no effect on fetlock or hock angles. Only 2D motion analysis was carried out. Results may have differed in horses with more extreme gait characteristics. Medium/extended trot increases extension of the fore- and hindlimb fetlock joints compared with collected trot in both young and mature dressage horses, respectively. © 2017 EVJ Ltd.

  3. Effect of Computer-Delivered Testing on Achievement in a Mastery Learning Course of Study with Partial Scoring and Variable Pacing.

    ERIC Educational Resources Information Center

    Evans, Richard M.; Surkan, Alvin J.

    The recent arrival of portable computer systems with high-level language interpreters now makes it practical to rapidly develop complex testing and scoring programs. These programs permit undergraduates access, at arbitrary times, to testing as an integral part of a mastery learning strategy. Effects of introducing the computer were studied by…

  4. The Opportunities of Contemporary Society in the Organization and Use of Childrens' Leisure Time

    ERIC Educational Resources Information Center

    Bajrami, Teuta Jusufi; Kadriu, Lulzime Lutfiu; Ceka, Ardita

    2016-01-01

    The rapid development undertaken in science, technique and technology, has strongly influenced the radical change of the pace of human existence, and therefore as a very important part in the everyday life of society along with mandatory time is regarded leisure time, also. Given the fact that free time as a pedagogical and sociological issue is…

  5. Beyond naturalness: Adapting wilderness stewardship to an era of rapid global change

    Treesearch

    David N. Cole

    2012-01-01

    Climate change and its effects are writ large across wilderness landscapes. They always have been and always will be (see Figure 1). But contemporary change is different. For the first time, the pace and direction of climate change appear to be driven significantly by human activities (IPCC 2007), and this change is playing out across landscapes already affected by...

  6. Qualitative Analysis of Organizational Change in One U.S. Dental School

    ERIC Educational Resources Information Center

    Crain, Geralyn Dell

    2010-01-01

    Currently, there is need for change in the way that dental schools in the United States educate their students to keep pace with the rapidly changing nature of the profession and to better address societal needs. Despite a well-documented change agenda put forth by individual authors and agencies both within and outside of dental education,…

  7. Literature Reviews on Wind Turbines and Health: Are They Enough?

    ERIC Educational Resources Information Center

    Horner, Brett; Jeffery, Roy D.; Krogh, Carmen M. E.

    2011-01-01

    Industrial wind turbines (IWTs) are a new source of community noise to which relatively few people have yet been exposed. IWTs are being erected at a rapid pace in proximity to human habitation. Some people report experiencing adverse health effects as a result of living in the environs of IWTs. In order to address public concerns and assess the…

  8. Clinician Beliefs and Practices in Dementia Care: Implications for Health Educators

    ERIC Educational Resources Information Center

    Meuser, Thomas M.; Boise, Linda; Morris, John C.

    2004-01-01

    Research on assessment and treatment of Alzheimer's disease (AD) is moving at a rapid pace. Continuing education (CE) providers must translate new findings for clinicians so as to enhance patient care. A two-page survey was distributed by mail to a sample of 5,000 licensed Missouri clinicians to gather data in support of this translation process.…

  9. State Requirements for Teacher Evaluation Policies Promoted by Race to the Top. NCEE Evaluation Brief. NCEE 2014-4016

    ERIC Educational Resources Information Center

    Hallgren, Kristin; James-Burdumy, Susanne; Perez-Johnson, Irma

    2014-01-01

    This brief describes the extent to which states required teacher evaluation policies aligned with the Race to the Top (RTT) initiative as of spring 2012. Although teacher evaluation policies appear to be rapidly evolving, documenting policy requirements in the early years of RTT implementation can help inform policymakers about the pace of policy…

  10. Strategic Studies Quarterly. Volume 10, Number 2, Summer 2016

    DTIC Science & Technology

    2016-01-01

    munitions, and networked command, control, communications , com- puters, intelligence, surveillance, and reconnaissance (C4ISR) has been a vital... communications , space capabilities, and networked intelligence, surveillance, and recon- naissance (ISR). The rapid pace of this proliferation is...intensity akin to that of the Manhattan Project or the Apollo Program. Building upon recent actions by Congress and DOD leadership, the next secretary of

  11. Keeping Pace With K-12 Online Learning: A Snapshot of State-Level Policy and Practice

    ERIC Educational Resources Information Center

    Watson, John F.; Winograd, Kathy; Kalmon, Stevan

    2004-01-01

    Online learning holds promise for providing new educational opportunities to a wide range of students across the country. The rapid expansion of K-12 online learning, however, threatens to outpace the development of appropriate state-level policies that serve to fulfill the promise. As the National Association of State Boards of Education warned…

  12. Issues for Universities Working with K-12 Institutions Implementing Prepackaged Pre-Engineering Curricula Such as Project Lead the Way

    ERIC Educational Resources Information Center

    Reid, Kenneth J.; Feldhaus, Charles R.

    2007-01-01

    The implementation of pre-engineering, standard curricula in K-12 schools is growing at a rapid pace. One such curriculum model, Project Lead the Way, consists of six standardized courses requiring significant training for teachers, specified laboratory equipment, standard topics, exams, etc. Schools implementing Project Lead the Way implement an…

  13. Corporate E-Learning: How Three Healthcare Companies Implement and Measure the Effectiveness of E-Learning

    ERIC Educational Resources Information Center

    Hodges, Allison

    2009-01-01

    Technological advancements such as the growth of the Internet provide opportunities for learning that are hard to resist. As technology continues to change at a rapid pace, e-learning has become an important priority of corporate education. E-learning is evolving as a way to train and enhance employee value by combining different learning styles…

  14. Hmong Americans: Issues and strategies related to outdoor recreation

    Treesearch

    David N. Bengston; Michele Schermann

    2008-01-01

    Immigration is an increasingly important factor in US society. According to the US Census Bureau, the foreign-born population increased by 57 percent from 1990 to 2000 and accounts for almost 12 percent of the US population as of 2005. The bureau's 2005 American Community Survey found that the rapid pace of immigration during the 1990s has continued. The arrival...

  15. Examining Harasim's Online Collaborative Learning Theory for Nursing Education

    ERIC Educational Resources Information Center

    Breen, Henny

    2013-01-01

    Online nursing education has been evolving at a rapid pace as it is recognized as offering the flexibility needed for practicing associate degree (ADN) and diploma prepared Registered Nurses to return to school to earn their BSN. At the same time, there is a paradigm shift in how nursing education is delivered. The focus has shifted from content…

  16. The Online Consumer: An Examination of Gender, Age, Income and Education as Determinants of Online Repurchasing

    ERIC Educational Resources Information Center

    Portillo, Carol D.

    2017-01-01

    Online purchasing has increased dramatically over the past 10 years and the pace is expected to continue to accelerate. This new channel of purchasing poses a challenge to online retailers as they strive to increase online repurchasing behavior. This non-experimental study addresses the problem of how to support a rapidly growing online…

  17. Paced Reading in Semantic Dementia: Word Knowledge Contributes to Phoneme Binding in Rapid Speech Production

    ERIC Educational Resources Information Center

    Jefferies, Elizabeth; Grogan, John; Mapelli, Cristina; Isella, Valeria

    2012-01-01

    Patients with semantic dementia (SD) show deficits in phoneme binding in immediate serial recall: when attempting to reproduce a sequence of words that they no longer fully understand, they show frequent migrations of phonemes between items (e.g., cap, frog recalled as "frap, cog"). This suggests that verbal short-term memory emerges directly from…

  18. Participation in Job-Related Lifelong Learning among Well-Educated Employees in the Nordic Countries

    ERIC Educational Resources Information Center

    Tikkanen, Tarja; Nissinen, Kari

    2016-01-01

    The purpose of this study was to explore participation in job-related lifelong learning (LLL) among well-educated mature workers and compare it across four Nordic countries. Although this group generally is very active in LLL, the centrality of knowledge work in society, rapid pace of skills-renewal and rising learning demands for all…

  19. News Coverage during International Political Uncertainty: The Korean Press Reports Sino-U.S. Normalization.

    ERIC Educational Resources Information Center

    Salwen, Michael B.

    The rapid pace of improving relations between the United States and the People's Republic of China during the late 1970s has been well scrutinized by mass media scholars, but most of the research has focused on the press coverage emanating from the United States, the People's Republic of China, and Taiwan, the major nations involved in…

  20. A call for standardized naming and reporting of human ESC and iPSC lines.

    PubMed

    Luong, Mai X; Auerbach, Jonathan; Crook, Jeremy M; Daheron, Laurence; Hei, Derek; Lomax, Geoffrey; Loring, Jeanne F; Ludwig, Tenneille; Schlaeger, Thorsten M; Smith, Kelly P; Stacey, Glyn; Xu, Ren-He; Zeng, Fanyi

    2011-04-08

    Human embryonic and induced pluripotent stem cell lines are being generated at a rapid pace and now number in the thousands. We propose a standard nomenclature and suggest the use of a centralized database for all cell line names and a minimum set of information for reporting new derivations. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Internet Use by Transition-Aged Youths with Visual Impairments in the United States: Assessing the Impact of Postsecondary Predictors

    ERIC Educational Resources Information Center

    Kelly, Stacy M.; Wolffe, Karen E.

    2012-01-01

    Introduction: Youths and adults without disabilities have been increasing the regularity of their online connectivity at a rapid pace, as previous research has indicated. The study presented here examined the degree to which transition-aged youths with visual impairments have used the Internet and what outcomes they have achieved following their…

  2. PERT/CPM and Supplementary Analytical Techniques. An Analysis of Aerospace Usage

    DTIC Science & Technology

    1978-09-01

    of a number of new...rapid pace of technological progress in the last 75 years has spawned the development of a. number of very interesting managorial tools, and one of ...support of the oversll effort. PR L g. At one time, use of PERT was mandatory on all major L]OD acquioition contracts . Since that time, the use of

  3. Higher Order Thinking in an Online World: Toward a Theory of Web-Mediated Knowledge Synthesis

    ERIC Educational Resources Information Center

    DeSchryver, Michael

    2014-01-01

    Background/Context: The rapid pace of technological change, undergirded by near ubiquitous access to the web, is producing a new learning ecology--a new ecology of information, of knowledge, of reading, of teaching, and of thinking. This instant availability of digital resources frees both time and cognitive energy that may be used to facilitate…

  4. The Future of Work, Business Education, and the Role of AACSB

    ERIC Educational Resources Information Center

    Beck-Dudley, Caryn L.

    2018-01-01

    In this keynote address to the Academy of Legal Studies in Business, delivered on September 8, 2017 in Savannah, Georgia, Karyn Beck-Dudley, discusses her new role as vice-chair/chair elect of Association to Advance Collegiate Schools of Business (AACSB), and the changing role of AACSB to keep pace with a rapidly changing education landscape. The…

  5. Investigating the Major Effect of Principal's Change Leadership on School Teachers' Professional Development

    ERIC Educational Resources Information Center

    Chang, Dian-Fu; Chen, Sheng-Nan; Chou, Wen-Ching

    2017-01-01

    In a rapidly changing era, educational change has become one of the crucial tasks for better student performance in schools. Potential and innovative leadership in schools is needed to keep up with the fast-pace of change, and to achieve better learning results for students. Therefore, how to construct a teacher's professional development to…

  6. Engaging the Online Student: Instructor-Created Video Content for the Online Classroom

    ERIC Educational Resources Information Center

    Underdown, Kimber; Martin, Jeff

    2016-01-01

    The online platform in higher education is growing at a rapid pace; however, detractors claim the lack of personal connection between student and teacher presence will never allow online to reach the same level of quality instruction found in a live classroom setting. While there will always be drawbacks with both the live classroom and online…

  7. Evolving Information Technology: A Case Study of the Effects of Constant Change on Information Technology Instructional Design Architecture

    ERIC Educational Resources Information Center

    Helps, Richard

    2010-01-01

    A major challenge for Information Technology (IT) programs is that the rapid pace of evolution of computing technology leads to frequent redesign of IT courses. The problem is exacerbated by several factors. Firstly, the changing technology is the subject matter of the discipline and is also frequently used to support instruction; secondly, this…

  8. Variation in genetic structure and gene flow across the range of Sequoiadendron giganteum (giant sequoia)

    Treesearch

    Rainbow DeSilva; Richard S. Dodd

    2017-01-01

    During this century, climate warming and altered precipitation patterns will lead to habitat changes that may be beneficial to some long-lived tree species and detrimental to others. Paleoendemics, with limited and disjunct distributions will face the greatest challenges, as migration rates will be too slow to keep pace with rapid environmental change and populations...

  9. One Year after the Revolution: Politics and Policies of Education in the Eastern German States.

    ERIC Educational Resources Information Center

    Reuter, Lutz R.

    Complaints about changes in East German education following the break-down of the communist system are widespread. Critics are dissatisfied with: (1) the rapid pace of change; (2) the lack of genuine East German solutions; (3) the loss of the German Democratic Republic's (GDR's) identity; (4) dominance by Western Germany; and (5) the lack of West…

  10. Nanobiotechnology: Cell Membrane-Based Delivery Systems.

    PubMed

    Zhang, Pengfei; Liu, Gang; Chen, Xiaoyuan

    2017-04-01

    The increasingly rapid pace of research in the field of bioinspired drug delivery systems is revealing the promise of cell membrane-based nanovesicles for biomedical applications. Those cell membrane-based nanoparticles combine the natural functionalities of cell plasma membranes and the bioengineering flexibility of synthetic nanomaterials, and such versatility provides a means of designing exciting new drug formulations for personalized treatment in future nanomedicine.

  11. Contemporary, emerging, and ratified wireless security standards: an update for the networked dental office.

    PubMed

    Mupparapu, Muralidhar

    2006-02-15

    Wireless networking is not new to contemporary dental offices around the country. Wireless routers and network cards have made access to patient records within the office handy and, thereby, saving valuable chair side time and increasing productivity. As is the case with any rapidly developing technology, wireless technology also changes with the same rate. Unless, the users of the wireless networking understand the implications of these changes and keep themselves updated periodically, the office network will become obsolete very quickly. This update of the emerging security protocols and pertaining to ratified wireless 802.11 standards will be timely for the contemporary dentist whose office is wirelessly networked. This article brings the practicing dentist up-to-date on the newer versions and standards in wireless networking that are changing at a fast pace. The introduction of newer 802.11 standards like super G, Super AG, Multiple Input Multiple Output (MIMO), and pre-n are changing the pace of adaptation of this technology. Like any other rapidly transforming technology, information pertaining to wireless networking should be a priority for the contemporary dentist, an eventual end-user in order to be a well-informed and techno-savvy consumer.

  12. Cadmium-containing nanoparticles: Perspectives on pharmacology and toxicology of quantum dots

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rzigalinski, Beverly A.; Strobl, Jeannine S.

    2009-08-01

    The field of nanotechnology is rapidly expanding with the development of novel nanopharmaceuticals that have potential for revolutionizing medical treatment. The rapid pace of expansion in this field has exceeded the pace of pharmacological and toxicological research on the effects of nanoparticles in the biological environment. The development of cadmium-containing nanoparticles, known as quantum dots, show great promise for treatment and diagnosis of cancer and targeted drug delivery, due to their size-tunable fluorescence and ease of functionalization for tissue targeting. However, information on pharmacology and toxicology of quantum dots needs much further development, making it difficult to assess the risksmore » associated with this new nanotechnology. Further, nanotechnology poses yet another risk for toxic cadmium, which will now enter the biological realm in nano-form. In this review, we discuss cadmium-containing quantum dots and their physicochemical properties at the nano-scale. We summarize the existing work on pharmacology and toxicology of cadmium-containing quantum dots and discuss perspectives in their utility in disease treatment. Finally, we identify critical gaps in our knowledge of cadmium quantum dot toxicity, and how these gaps need to be assessed to enable quantum dot nanotechnology to transit safely from bench to bedside.« less

  13. Effects of atorvastatin on atrial remodeling in a rabbit model of atrial fibrillation produced by rapid atrial pacing.

    PubMed

    Yang, Qian; Qi, Xiaoyong; Dang, Yi; Li, Yingxiao; Song, Xuelian; Hao, Xiao

    2016-06-24

    Accumulating evidence suggests that myeloperoxidase (MPO) is involved in atrial remodeling of atrial fibrillation (AF). Statins could reduce the MPO levels in patients with cardiovascular diseases. This study evaluated the effects of atorvastatin on MPO level and atrial remodeling in a rabbit model of pacing-induced AF. Eighteen rabbits were randomly divided into sham, control and atorvastatin groups. Rabbits in the control and atorvastatin groups were subjected to rapid atrial pacing (RAP) at 600 bpm for 3 weeks, and treated with placebo or atorvastatin (2.5 mg/kg/d), respectively. Rabbits in the sham group did not receive RAP. After 3 weeks of pacing, atrial structural and functional changes were assessed by echocardiography, atrial effective refractory period (AERP) and AF inducibility were measured by atrial electrophysiological examination, and histological changes were evaluated by Masson trichrome-staining. The L-type calcium channel α1c (Cav1.2), collagen I and III, MPO, matrix metalloproteinase (MMP)-2 and MMP-9 were analyzed by real time polymerase chain reaction and/or western blot. All rabbits were found to have maintained sinus rhythm after 3 weeks of RAP. Atrial burst stimulation induced sustained AF (>30 min) in 5, 4, and no rabbits in the control, atorvastatin, and sham groups, respectively. The AERP shortened and Cav1.2 mRNA level decreased in the control group, but these changes were suppressed in the atorvastatin group. Obvious left atrial enlargement and dysfunction was found in both control and atorvastatin groups. Compared with the control group, these echocardiograhic indices of left atrium did not differ in the atorvastatin group. Prominent atrial fibrosis and increased levels of collagen I and III were observed in the control group but not in the atorvastatin group. The mRNA and protein levels of MPO, MMP-2 and MMP-9 significantly increased in the control group, but these changes were prevented in the atorvastatin group. Treatment with atorvastatin prevented atrial remodeling in a rabbit model of RAP-induced AF. The reduction of levels of atrial MPO, MMP-2 and MMP-9 may contribute to the prevention of atorvastatin on atrial remodeling.

  14. Recombinant glucagon-like peptide-1 increases myocardial glucose uptake and improves left ventricular performance in conscious dogs with pacing-induced dilated cardiomyopathy.

    PubMed

    Nikolaidis, Lazaros A; Elahi, Dariush; Hentosz, Teresa; Doverspike, Aaron; Huerbin, Rhonda; Zourelias, Lee; Stolarski, Carol; Shen, You-tang; Shannon, Richard P

    2004-08-24

    The failing heart demonstrates a preference for glucose as its metabolic substrate. Whether enhancing myocardial glucose uptake favorably influences left ventricular (LV) contractile performance in heart failure remains uncertain. Glucagon-like peptide-1 (GLP-1) is a naturally occurring incretin with potent insulinotropic effects the action of which is attenuated when glucose levels fall below 4 mmol. We examined the impact of recombinant GLP-1 (rGLP-1) on LV and systemic hemodynamics and myocardial substrate uptake in conscious dogs with advanced dilated cardiomyopathy (DCM) as a mechanism for overcoming myocardial insulin resistance and enhancing myocardial glucose uptake. Thirty-five dogs were instrumented and studied in the fully conscious state. Advanced DCM was induced by 28 days of rapid pacing. Sixteen dogs with advanced DCM received a 48-hour infusion of rGLP-1 (1.5 pmol x kg(-1) x min(-1)). Eight dogs with DCM served as controls and received 48 hours of a saline infusion (3 mL/d). Infusion of rGLP-1 was associated with significant (P<0.02) increases in LV dP/dt (98%), stroke volume (102%), and cardiac output (57%) and significant decreases in LV end-diastolic pressure, heart rate, and systemic vascular resistance. rGLP-1 increased myocardial insulin sensitivity and myocardial glucose uptake. There were no significant changes in the saline control group. rGLP-1 dramatically improved LV and systemic hemodynamics in conscious dogs with advanced DCM induced by rapid pacing. rGLP-1 has insulinomimetic and glucagonostatic properties, with resultant increases in myocardial glucose uptake. rGLP-1 may be a useful metabolic adjuvant in decompensated heart failure.

  15. Health costs of reproduction are minimal despite high fertility, mortality and subsistence lifestyle

    PubMed Central

    Gurven, Michael; Costa, Megan; Ben Trumble; Stieglitz, Jonathan; Beheim, Bret; Eid Rodriguez, Daniel; Hooper, Paul L.; Kaplan, Hillard

    2016-01-01

    Women exhibit greater morbidity than men despite higher life expectancy. An evolutionary life history framework predicts that energy invested in reproduction trades-off against investments in maintenance and survival. Direct costs of reproduction may therefore contribute to higher morbidity, especially for women given their greater direct energetic contributions to reproduction. We explore multiple indicators of somatic condition among Tsimane forager-horticulturalist women (Total Fertility Rate = 9.1; n =  592 aged 15–44 years, n = 277 aged 45+). We test whether cumulative live births and the pace of reproduction are associated with nutritional status and immune function using longitudinal data spanning 10 years. Higher parity and faster reproductive pace are associated with lower nutritional status (indicated by weight, body mass index, body fat) in a cross-section, but longitudinal analyses show improvements in women’s nutritional status with age. Biomarkers of immune function and anemia vary little with parity or pace of reproduction. Our findings demonstrate that even under energy-limited and infectious conditions, women are buffered from the potential depleting effects of rapid reproduction and compound offspring dependency characteristic of human life histories. PMID:27436412

  16. Acute effect of L-arginine on hemodynamics and vascular capacitance in the canine pacing model of heart failure.

    PubMed

    Ogilvie, R I; Zborowska-Sluis, D

    1995-09-01

    The effect of L-arginine, 250 mg/kg over 10 min, on hemodynamics and venous function was studied in nine splenectomized dogs under light pentobarbital anesthesia before and after 17 +/- 1 days of rapid right ventricular pacing (RRVP) at 250 beats/min. Chronic RRVP induced mild congestive heart failure with increased mean circulatory filling (Pmcf), right atrial (Pra) and pulmonary capillary wedge pressures (Ppcw), and reduced cardiac output (CO). During the development of heart failure, total vascular compliance assessed from Pmcf-blood volume relationships during circulatory arrest was unchanged, but total vascular capacitance was markedly reduced, with an increase in stressed and reduction in unstressed blood volumes. At baseline but not after RRVP, L-arginine increased CO and reduced pulmonary vascular resistance. There were no significant changes in Pra, Ppcw, or total peripheral resistance. L-Arginine failed to alter total vascular compliance and capacitance or central blood volume in the baseline or failure state. These results do not support the hypothesis that increased Pmcf and reduced total vascular capacitance in the early stages of pacing-induced heart failure are caused by reduced substrate availability for or an endogenous competitive antagonist of NO synthase in venous endothelial cells.

  17. Booster vaccinations: can immunologic memory outpace disease pathogenesis?

    PubMed

    Pichichero, Michael E

    2009-12-01

    Almost all current vaccines work by the induction of antibodies in serum or on the mucosa to block adherence of pathogens to epithelial cells or interfere with microbial invasion of the bloodstream. However, antibody levels usually decline after vaccination to undetectable amounts if further vaccination does not occur. Persistence of vaccine-induced antibodies usually goes well beyond the time when they should have decayed to undetectable levels because of ongoing "natural" boosting or other immunologic mechanisms. The production of memory B and T cells is of clear importance, but the likelihood that a memory response will be fast enough in the absence of a protective circulating antibody level likely depends on the pace of pathogenesis of a specific organism. This concept is discussed with regard to Haemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis; hepatitis A and B; diphtheria, tetanus, and pertussis; polio, measles, mumps, rubella, and varicella; rotavirus; and human papilloma virus. With infectious diseases for which the pace of pathogenesis is less rapid, some individuals will contract infection before the memory response is fully activated and implemented. With infectious diseases for which the pace of pathogenesis is slow, immune memory should be sufficient to prevent disease.

  18. Reduced intrinsic heart rate is associated with reduced arrhythmic susceptibility in guinea-pig heart.

    PubMed

    Osadchii, Oleg E

    2014-12-01

    In the clinical setting, patients with slower resting heart rate are less prone to cardiovascular death compared with those with elevated heart rate. However, electrophysiological adaptations associated with reduced cardiac rhythm have not been thoroughly explored. In this study, relationships between intrinsic heart rate and arrhythmic susceptibility were examined by assessments of action potential duration (APD) rate adaptation and inducibility of repolarization alternans in sinoatrial node (SAN)-driven and atrioventricular (AV)-blocked guinea-pig hearts perfused with Langendorff apparatus. Electrocardiograms, epicardial monophasic action potentials, and effective refractory periods (ERP) were assessed in normokalemic and hypokalemic conditions. Slower basal heart rate in AV-blocked hearts was associated with prolonged ventricular repolarization during spontaneous beating, and with attenuated APD shortening at increased cardiac activation rates during dynamic pacing, when compared with SAN-driven hearts. During hypokalemic perfusion, the inducibility of repolarization alternans and tachyarrhythmia by rapid pacing was found to be lower in AV-blocked hearts. This difference was ascribed to prolonged ERP in the setting of reduced basal heart rate, which prevented ventricular capture at critically short pacing intervals required to induce arrhythmia. Reduced basal heart rate is associated with electrophysiological changes that prevent electrical instability upon an abrupt cardiac acceleration.

  19. The Effects of Shoe Traction and Obstacle Height on Lower Extremity Coordination Dynamics during Walking

    PubMed Central

    Decker, Leslie; Houser, Jeremy J.; Noble, John M.; Karst, Gregory M.; Stergiou, Nicholas

    2009-01-01

    This study aims to investigate the effects of shoe traction and obstacle height on lower extremity relative phase dynamics (analysis of intralimb coordination) during walking to better understand the mechanisms employed to avoid slippage following obstacle clearance. Ten participants walked at a self-selected pace during eight conditions: four obstacle heights (0%, 10%, 20%, and 40% of limb length) while wearing two pairs of shoes (low and high traction). A coordination analysis was used and phasing relationships between lower extremity segments were examined. The results demonstrated that significant behavioral changes were elicited under varied obstacle heights and frictional conditions. Both decreasing shoe traction and increasing obstacle height resulted in a more in-phase relationship between the interacting lower limb segments. The higher the obstacle and the lower the shoe traction, the more unstable the system became. These changes in phasing relationship and variability are indicators of alterations in coordinative behavior, which if pushed further may have lead to falling. PMID:19187929

  20. Plasma Metabolomics Biosignature According to HIV Stage of Infection, Pace of Disease Progression, Viremia Level and Immunological Response to Treatment

    PubMed Central

    Scarpelini, Bruno; Zanoni, Michelle; Sucupira, Maria Cecilia Araripe; Truong, Hong-Ha M.; Janini, Luiz Mario Ramos; Segurado, Ismael Dale Cotrin; Diaz, Ricardo Sobhie

    2016-01-01

    Background We evaluated plasma samples HIV-infected individuals with different phenotypic profile among five HIV-infected elite controllers and five rapid progressors after recent HIV infection and one year later and from 10 individuals subjected to antiretroviral therapy, five of whom were immunological non-responders (INR), before and after one year of antiretroviral treatment compared to 175 samples from HIV-negative patients. A targeted quantitative tandem mass spectrometry metabolomics approach was used in order to determine plasma metabolomics biosignature that may relate to HIV infection, pace of HIV disease progression, and immunological response to treatment. Results Twenty-five unique metabolites were identified, including five metabolites that could distinguish rapid progressors and INRs at baseline. Severe deregulation in acylcarnitine and sphingomyelin metabolism compatible with mitochondrial deficiencies was observed. β-oxidation and sphingosine‐1‐phosphate-phosphatase-1 activity were down-regulated, whereas acyl-alkyl-containing phosphatidylcholines and alkylglyceronephosphate synthase levels were elevated in INRs. Evidence that elite controllers harbor an inborn error of metabolism (late-onset multiple acyl-coenzyme A dehydrogenase deficiency [MADD]) was detected. Conclusions Blood-based markers from metabolomics show a very high accuracy of discriminating HIV infection between varieties of controls and have the ability to predict rapid disease progression or poor antiretroviral immunological response. These metabolites can be used as biomarkers of HIV natural evolution or treatment response and provide insight into the mechanisms of the disease. PMID:27941971

  1. State-of-the-art methodology of forest inventory: a symposium proceedings.

    Treesearch

    Vernon J. LaBau; Tiberius Cunia

    1990-01-01

    The state-of-the-art of forest inventory methodology, being closely integrated with the fast-moving, high technology computer world, has been changing at a rapid pace over the past decade. Several successful conferences were held during the 1980s with the goal and purpose of staying abreast of such change. This symposium was conceived, not just with the idea of helping...

  2. An MBA Cohort's Use of an Enterprise Social Network for Collaborative Learning

    ERIC Educational Resources Information Center

    Murphy, Glen D.

    2016-01-01

    The rapid pace of social media means that our understanding of the way in which it facilitates the learning process continues to lag. The findings of a longitudinal study of an executive MBA cohort over a period of eight months in their use of the social media application Yammer is presented. Student interaction data was analysed using a form of…

  3. Reflective Practice and Readiness for Self-Directed Learning in Anesthesiology Residents Training in the United States

    ERIC Educational Resources Information Center

    Miller Juve, Amy Katrina

    2012-01-01

    The science and technology of medicine is evolving and changing at a fast pace. With these rapid advances, it is paramount that physicians maintain a level of medical knowledge that is current and relevant to their practice in order to address the challenges of patient care and safety. One way physicians can maintain a level of medical knowledge…

  4. CrossTalk: The Journal of Defense Software Engineering. Volume 20, Number 7

    DTIC Science & Technology

    2007-07-01

    away from the current Global Command and Control System family of systems, this effort will also require a significant change in both mindset and...which complicate the already significant logistic problems in austere environ- ments. Several efforts are beginning to produce rapidly deployable...currency, and applicability to keep pace with the changing environment and address significant challenges they face. Defense Information Systems Agency

  5. 5 Considerations for Digital Age Leaders: What Principals and District Administrators Need to Know about Tech Integration Today

    ERIC Educational Resources Information Center

    Larson, Lotta; Miller, Teresa; Ribble, Mike

    2010-01-01

    Technology has forever altered the way one learns and teaches, and the pace of change is only accelerating. What was hot last year or even last month may be of little interest today. How can educational leaders keep up with the daily onslaught of information when new literacies rapidly outpace traditional literacies, and access to technology and…

  6. Greek Kindergarten Teachers' and Parents' Views about Changes in Play since Their Own Childhood

    ERIC Educational Resources Information Center

    Doliopoulou, Elsie; Rizou, Charitomeni

    2012-01-01

    Play is both a right of children and a learning method for preschoolers and school aged children. It is influenced by all forms of social change on a local and global level. The rapid pace of life and the competitive modern lifestyle, particularly in western societies, are leading to a decrease in spontaneous play and to its replacement by more…

  7. Improving Secondary Career and Technical Education through Professional Development: Alternative Certification and Use of Technical Assessment Data

    ERIC Educational Resources Information Center

    National Research Center for Career and Technical Education, 2011

    2011-01-01

    Secondary career and technical education (CTE) is a field in transition. It is moving from a primary focus on preparing students for entry-level employment to preparing them for continuing education and training as well as employment. The rapid pace of change in technology and the global economy has created a demand for workers who are able to…

  8. I.T. Changes: An Exploration of the Relationship between Motivation, Trust, and Resistance to Change in Information Technology

    ERIC Educational Resources Information Center

    Culmer, Nathan Paul

    2012-01-01

    Change is an organizational inevitability. There are few fields that undergo change more rapidly than information technology. Keeping up with the pace of change in a field so inclined toward change may take a unique toll on workers in information technology. Yet, little has been done to investigate workers' orientations towards change in this…

  9. The evolution of mapping habitat for northern spotted owls (Strix occidentalis caurina): A comparison of photo-interpreted, Landsat-based, and lidar-based habitat maps

    Treesearch

    Steven H. Ackers; Raymond J. Davis; Keith A. Olsen; Katie M. Dugger

    2015-01-01

    Wildlife habitat mapping has evolved at a rapid pace over the last fewdecades. Beginning with simple, often subjective, hand-drawn maps, habitat mapping now involves complex species distribution models (SDMs) using mapped predictor variables derived from remotely sensed data. For species that inhabit large geographic areas, remote sensing technology is often...

  10. Oak, fire, and global change in the eastern USA: what might the future hold?

    Treesearch

    James M. Vose; Katherine Elliott

    2016-01-01

    The pace of environmental and socioeconomic change over the past 100 years has been rapid. Changes in fire regimes, climate, and land use have shaped the structure and function of most forest ecosystems, including oak (Quercus spp. L.) forests in the eastern United States.New stressors such as air pollution and invasive species have contributed to...

  11. Elevating the Civic Science Literacy of American Adults: Assessing a Renewed Citizen Science Paradigm Integrating Nonformal Outdoor Adult Education and Enhanced Experiential Learning

    ERIC Educational Resources Information Center

    Cronin, David Patrick

    2011-01-01

    America's adult populace has failed to keep pace with the rapid inundation of science-centric advancements affecting nearly every facet of personal and public life. With deficiencies in areas of science knowledge, America's adult populace is characterized as civic science illiterate. This research constructed and employed the renewed citizen…

  12. Chris Pierce and the Yankee Donut Company: An E-Mail-Based Management Simulation

    ERIC Educational Resources Information Center

    Greenberg, Danna N.; Rollag, Keith

    2005-01-01

    In this article, the authors describe an e-mail-based simulation that helps students experience the fast-paced, complex world of the middle manager. In this electronic in-basket exercise, students assume the role of a district manager in a doughnut company as they respond to a rapid series of high- and low-priority e-mails ostensibly sent from…

  13. Ethical and Moral Dimensions of the Professionalization of Teachers: Lessons To Be Learned from Doctors and Lawyers.

    ERIC Educational Resources Information Center

    Smith, Timothy H.

    In response to greater public awareness and concern, members of the legal and medical professions have begun to acknowledge that they have leadership roles to play in the shaping of public policies affecting the common good. The rapid pace of social change and scientific development has lent a new sense of urgency to the need for these two…

  14. Rural Dispositions of Floating Children within the Field of Beijing Schools: Can Disadvantaged Rural Habitus Turn into Recognised Cultural Capital?

    ERIC Educational Resources Information Center

    Mu, Guanglun Michael; Jia, Ning

    2016-01-01

    The rapid pace of urbanisation in China has seen a massive increase in the movement of the rural population to work and live in urban regions. In this large-scale migration context, the educational, health, and psychological problems of floating children are becoming increasingly visible. Different from extant studies, we focus our investigation…

  15. Biotechnology Education. Engaging the Learner: Embedding Information Literacy Skills into a Biotechnology Degree

    ERIC Educational Resources Information Center

    Ward, Helena; Hockey, Julie

    2007-01-01

    One of the challenges of the Biotechnology industry is keeping up to date with the rapid pace of change and that much of the information, which students learn in their undergraduate studies, will be out of date in a few years. It is therefore crucial that Biotechnology students have the skills to access the relevant information for their studies…

  16. The FRAME Project - A collaborative modeling approach to natural resource management at Mesa Verde National Park

    Treesearch

    Christine E. Turner; William H. Romme; Jim Chew; Mark E. Miller; Lisa Floyd-Hanna Leavesley; George San Miguel; Neil Cobb; Richard Zirbes; Roland Viger; Kirsten Ironside

    2008-01-01

    The rapid pace of social and environmental changes over the past few decades has presented significant challenges for the people who manage our public lands. Demographic shifts have placed large populations in close proximity to public lands and have resulted in increased public scrutiny of decision making on those lands. Natural resource managers are required to make...

  17. Living and Leading in a Digital Age: A Narrative Study of the Attitudes and Perceptions of School Leaders about Media Literacy

    ERIC Educational Resources Information Center

    Mahoney, Kerrigan R.; Khwaja, Tehmina

    2016-01-01

    Students graduating from K-12 education need media literacy skills to engage, participate, and learn in a world in which literacy must keep pace with rapidly changing technologies. Given the significant roles school administrators play in providing leadership and vision to their schools, this narrative study addresses the research question: What…

  18. Current state of the art for statistical modeling of species distributions [Chapter 16

    Treesearch

    Troy M. Hegel; Samuel A. Cushman; Jeffrey Evans; Falk Huettmann

    2010-01-01

    Over the past decade the number of statistical modelling tools available to ecologists to model species' distributions has increased at a rapid pace (e.g. Elith et al. 2006; Austin 2007), as have the number of species distribution models (SDM) published in the literature (e.g. Scott et al. 2002). Ten years ago, basic logistic regression (Hosmer and Lemeshow 2000)...

  19. A fully implantable pacemaker for the mouse: from battery to wireless power.

    PubMed

    Laughner, Jacob I; Marrus, Scott B; Zellmer, Erik R; Weinheimer, Carla J; MacEwan, Matthew R; Cui, Sophia X; Nerbonne, Jeanne M; Efimov, Igor R

    2013-01-01

    Animal models have become a popular platform for the investigation of the molecular and systemic mechanisms of pathological cardiovascular physiology. Chronic pacing studies with implantable pacemakers in large animals have led to useful models of heart failure and atrial fibrillation. Unfortunately, molecular and genetic studies in these large animal models are often prohibitively expensive or not available. Conversely, the mouse is an excellent species for studying molecular mechanisms of cardiovascular disease through genetic engineering. However, the large size of available pacemakers does not lend itself to chronic pacing in mice. Here, we present the design for a novel, fully implantable wireless-powered pacemaker for mice capable of long-term (>30 days) pacing. This design is compared to a traditional battery-powered pacemaker to demonstrate critical advantages achieved through wireless inductive power transfer and control. Battery-powered and wireless-powered pacemakers were fabricated from standard electronic components in our laboratory. Mice (n = 24) were implanted with endocardial, battery-powered devices (n = 14) and epicardial, wireless-powered devices (n = 10). Wireless-powered devices were associated with reduced implant mortality and more reliable device function compared to battery-powered devices. Eight of 14 (57.1%) mice implanted with battery-powered pacemakers died following device implantation compared to 1 of 10 (10%) mice implanted with wireless-powered pacemakers. Moreover, device function was achieved for 30 days with the wireless-powered device compared to 6 days with the battery-powered device. The wireless-powered pacemaker system presented herein will allow electrophysiology studies in numerous genetically engineered mouse models as well as rapid pacing-induced heart failure and atrial arrhythmia in mice.

  20. A disruptive sequencer meets disruptive publishing.

    PubMed

    Loman, Nick; Goodwin, Sarah; Jansen, Hans; Loose, Matt

    2015-01-01

    Nanopore sequencing was recently made available to users in the form of the Oxford Nanopore MinION. Released to users through an early access programme, the MinION is made unique by its tiny form factor and ability to generate very long sequences from single DNA molecules. The platform is undergoing rapid evolution with three distinct nanopore types and five updates to library preparation chemistry in the last 18 months. To keep pace with the rapid evolution of this sequencing platform, and to provide a space where new analysis methods can be openly discussed, we present a new F1000Research channel devoted to updates to and analysis of nanopore sequence data.

  1. Avionics Architectures for Exploration: Building a Better Approach for (Human) Spaceflight Avionics

    NASA Technical Reports Server (NTRS)

    Goforth, Montgomery B.; Ratliff, James E.; Hames, Kevin L.; Vitalpur, Sharada V.

    2014-01-01

    The field of Avionics is advancing far more rapidly in terrestrial applications than in space flight applications. Spaceflight Avionics are not keeping pace with expectations set by terrestrial experience, nor are they keeping pace with the need for increasingly complex automation and crew interfaces as we move beyond Low Earth Orbit. NASA must take advantage of the strides being made by both space-related and terrestrial industries to drive our development and sustaining costs down. This paper describes ongoing efforts by the Avionics Architectures for Exploration (AAE) project chartered by NASA's Advanced Exploration Systems (AES) Program to evaluate new avionic architectures and technologies, provide objective comparisons of them, and mature selected technologies for flight and for use by other AES projects. Results from the AAE project's FY13 efforts are discussed, along with the status of FY14 efforts and future plans.

  2. Concordance and discordance between two measures of lower extremity function: 400 meter self-paced walk and SPPB.

    PubMed

    Sayers, Stephen P; Guralnik, Jack M; Newman, Anne B; Brach, Jennifer S; Fielding, Roger A

    2006-04-01

    The purpose of the study was to assess the concurrent validity of the 400 meter self-paced walk test (400-m W) against the commonly used short physical performance battery (SPPB). A secondary purpose was to determine whether the 400-m W could better discriminate physical performance among high functioning older adults by examining the distribution of 400-m W scores. 101 men and women (80.8+/-0.4 years) were recruited to participate in the study. The 400-mW and SPPB assessed lower extremity function. Lower extremity muscle strength, power, and contraction velocity was assessed using bilateral leg press (LP). Health history was obtained with questionnaire. 400-m W demonstrated moderate correlations with SPPB (Pearson r=0.74; p< 0.001). In 36 high functioning individuals (SPPB score= 10, 11, 12), participants above the median 400-m W performance time (n=20) had more medical conditions (2.8+/-0.4 vs 1.7+/-0.3; p=0.038), more reported falls (0.80+/-0.2 vs 0.19+/-0.1; p=0.016), more medications (3.7+/-0.4 vs 1.8+/-0.4; p=0.001), had lower LP power at 70% of the one repetition maximum (1RM) (336+/-45 W vs 663+/-78 W; p=0.001) and 40% 1RM (329+/-43 W vs 580+/-75 W; p=0.005), and had slower LP contraction velocity at 40% 1RM (77+/-5.5 m/s vs 112+/-8.4 m/s; p=0.001) compared with those below the median (n=16). A substantial number of apparently well functioning older adults demonstrated some limitations in the ability to walk 400 meters. Use of the 400-m W may be justified to obtain information to better discriminate among high functioning elderly.

  3. Social Franchising: A Blockbuster to Address Unmet Need for Family Planning and to Advance Toward the FP2020 Goal.

    PubMed

    2015-06-17

    Social franchising has scaled-up provision of voluntary family planning, especially long-acting reversible contraceptives, across Africa and Asia at a rapid and remarkable pace. The approach should be pursued vigorously, especially in countries with a significant private-sector presence, to advance the FP2020 goal of providing access to modern contraception to 120 million additional clients by 2020.

  4. An Exploratory Study of the Role of Teaching Experience in Motivation and Academic Achievement in a Virtual Ninth Grade English I Course

    ERIC Educational Resources Information Center

    Carpenter, Julia Kathryn

    2011-01-01

    Virtual K-12 schools are growing rapidly in the U.S., providing students the opportunity to learn at their own pace. Lack of motivation has been cited as a major cause of failure to succeed by distance education students (Kim & Keller, 2008; Moore & Kearsley, 1996). To address this issue, distance educators need to identify what specific…

  5. Accelerating Software Development through Agile Practices--A Case Study of a Small-Scale, Time-Intensive Web Development Project at a College-Level IT Competition

    ERIC Educational Resources Information Center

    Zhang, Xuesong; Dorn, Bradley

    2012-01-01

    Agile development has received increasing interest both in industry and academia due to its benefits in developing software quickly, meeting customer needs, and keeping pace with the rapidly changing requirements. However, agile practices and scrum in particular have been mainly tested in mid- to large-size projects. In this paper, we present…

  6. Higher Education and the Global Marketplace: Entrepreneurial Activity in a Dynamic Environment. Twenty-Seventh Annual Earl V. Pullias Lecture Series in Higher Education. Fall 2004

    ERIC Educational Resources Information Center

    Armstrong, Lloyd; Becker, Douglas

    2004-01-01

    Among the most dynamic influences affecting higher education is the increase in the for-profit postsecondary industry. In 2002, for-profit institutions constituted 12% of the four-year colleges and universities in the United States, continuing a rapid pace of growth that began in the late twentieth century (NCES, 2003). As the economy moves…

  7. Designing and Publication of Interactive E-Book for Students of Princess Nourah Bint Abdulrahman University: An Empirical Study

    ERIC Educational Resources Information Center

    Alshaya, Hessah; Oyaid, Afnan

    2017-01-01

    The present study aims to keep pace with the rapid developments in the field of e-learning which includes the widespread use of e-books. Therefore, the authors conducted a pilot study on (55) faculty members from various disciplines, they assured the importance of e-books in education and the need for them. Accordingly, the authors designed and…

  8. Day-Care Regulation: Serving Children or Bureaucrats? Cato Institute Policy Analysis No. 59.

    ERIC Educational Resources Information Center

    Lehrman, Karen; Pace, Jana

    If the supply of day care is ever to keep pace with the rapidly rising demand, it is essential that there be a favorable climate for its growth. At present there is not, and the regulatory obstacle course laid out by state and local officials is in large part why. State barriers to the provision of day care involve licensing and registration and…

  9. Statistical and Clustering Based Rules Extraction Approaches for Fuzzy Model to Estimate Academic Performance in Distance Education

    ERIC Educational Resources Information Center

    Yildiz, Osman; Bal, Abdullah; Gulsecen, Sevinc

    2015-01-01

    The demand for distance education has been increasing at a rapid pace all around the world. This, in turn, places a special importance on the need for the development of more distance education systems. However, there is an alarming rise in the number of distance education students that drop out of the system without asking for any help. The…

  10. Reviewing the Purpose of Education and Challenges Faced in Implementing Sound Pedagogical Practices in the Presence of Emerging Evidence from Neuroscience

    ERIC Educational Resources Information Center

    Watagodakumbura, Chandana

    2015-01-01

    The field of neuroscience has been evolving constantly and at a rapid pace in the recent past. Consequently, neuroscientists have put forth a wealth of knowledge in relation learning and education in general. In this context, how can we as educators benefit from the emerging evidence from neuroscience so that we can take a significant step forward…

  11. Special Inspector General for Afghanistan Reconstruction (SIGAR)

    DTIC Science & Technology

    2013-01-30

    to MAIL to provide rapid disbursement of loans across the agricultural value chain through banks, farm stores, leasing companies, and food pro ...educated, and pro - fessional staff in order to plan and execute operations at a requisite pace.”23 Routine support for the ANSF also poses a capacity...of vehicles receiving maintenance, (2) the contractor performed within the terms and conditions of the contract, and (3) DoD agencies pro - vided

  12. The Virtual Combat Air Staff. The Promise of Information Technologies,

    DTIC Science & Technology

    1996-08-07

    development of specialists . The need for advance planning and orchestration of a growing variety of sup- port functions has required the commander to... ability for almost unlim- ited access to command authorities and fielded forces via worldwide communications, increased situational awareness, and the...mercially developed systems that incorporate the latest technologies, training programs will have to adapt to the rapid pace at which such technologies are

  13. Variability in climate and productivity during the Paleocene-Eocene Thermal Maximum in the western Tethys (Forada section)

    NASA Astrophysics Data System (ADS)

    Giusberti, L.; Boscolo Galazzo, F.; Thomas, E.

    2016-02-01

    The Forada section (northeastern Italy) provides a continuous, expanded deep-sea record of the Paleocene-Eocene Thermal Maximum (PETM) in the central-western Tethys. We combine a new, high-resolution, benthic foraminiferal assemblage record with published calcareous plankton, mineralogical and biomarker data to document climatic and environmental changes across the PETM, highlighting the benthic foraminiferal extinction event (BEE). The onset of the PETM, occurring ˜ 30 kyr after a precursor event, is marked by a thin, black, barren clay layer, possibly representing a brief pulse of anoxia and carbonate dissolution. The BEE occurred within the 10 cm interval including this layer. During the first 3.5 kyr of the PETM, several agglutinated recolonizing taxa show rapid species turnover, indicating a highly unstable, CaCO3-corrosive environment. Calcareous taxa reappeared after this interval, and the next ˜9 kyr were characterized by rapid alternation of peaks in abundance of various calcareous and agglutinated recolonizers. These observations suggest that synergistic stressors, including deepwater CaCO3 corrosiveness, low oxygenation, and high environmental instability caused the extinction. Combined faunal and biomarker data (BIT index, higher plant n-alkane average chain length) and the high abundance of the mineral chlorite suggest that erosion and weathering increased strongly at the onset of the PETM, due to an overall wet climate with invigorated hydrological cycle, which led to storm flood events carrying massive sediment discharge into the Belluno Basin. This interval was followed by the core of the PETM, characterized by four precessionally paced cycles in CaCO3 %, hematite %, δ13C, abundant occurrence of opportunistic benthic foraminiferal taxa, and calcareous nannofossil and planktonic foraminiferal taxa typical of high-productivity environments, radiolarians, and lower δDn-alkanes. We interpret these cycles as reflecting alternation between an overall arid climate, characterized by strong winds and intense upwelling, and an overall humid climate, with abundant rains and high sediment delivery (including refractory organic carbon) from land. Precessionally paced marl-limestone couplets occur throughout the recovery interval of the carbon isotope excursion (CIE) and up to 10 m above it, suggesting that these wet-dry cycles persisted, though at declining intensity, after the peak PETM. Enhanced climate extremes at mid-latitudes might have been a direct response to the massive CO2 input in the ocean atmosphere system at the Paleocene-Eocene transition, and may have had a primary role in restoring the Earth system to steady state.

  14. Benthic foraminifera at the Paleocene/Eocene thermal maximum in the western Tethys (Forada section): variability in climate and productivity

    NASA Astrophysics Data System (ADS)

    Giusberti, L.; Boscolo Galazzo, F.; Thomas, E.

    2015-09-01

    The Forada section (northeastern Italy) provides a continuous, expanded deep-sea record of the Paleocene/Eocene thermal maximum (PETM) in the central-western Tethys. We combine a new, high resolution, benthic foraminiferal assemblage record with published calcareous plankton, mineralogical and biomarker data to document climatic and environmental changes across the PETM, highlighting the benthic foraminiferal extinction event (BEE). The onset of the PETM, occurring ~ 30 kyr after a precursor event, is marked by a thin, black, barren clay layer, possibly representing a brief pulse of anoxia and carbonate dissolution. The BEE occurred within the 10 cm interval including this layer. During the first 3.5 kyr of the PETM several agglutinated recolonizing taxa show rapid species turnover, indicating a highly unstable, CaCO3-corrosive environment. Calcareous taxa reappeared after this interval, and the next ~ 9 kyr were characterized by rapid alternation of peaks in abundance of various calcareous and agglutinant recolonizers. These observations suggest that synergistic stressors including deep water CaCO3-corrosiveness, low oxygenation, and high environmental instability caused the extinction. Combined faunal and biomarker data (BIT index, higher plant n-alkane average chain length) and the high abundance of the mineral chlorite suggest that erosion and weathering increased strongly at the onset of the PETM, due to an overall wet climate with invigorated hydrological cycle, which led to storm flood-events carrying massive sediment discharge into the Belluno Basin. This interval was followed by the core of the PETM, characterized by four precessionally paced cycles in CaCO3%, hematite%, δ13C, abundant occurrence of opportunistic benthic foraminiferal taxa, as well as calcareous nannofossil and planktonic foraminiferal taxa typical of high productivity environments, radiolarians, and lower δDn-alkanes. We interpret these cycles as reflecting alternation between an overall arid climate, characterized by strong winds and intense upwelling, with an overall humid climate, with abundant rains and high sediment delivery (including refractory organic carbon) from land. Precessionally paced marl-limestone couplets occur throughout the recovery interval of the CIE and up to ten meters above it, suggesting that these wet-dry cycles persisted, though at declining intensity, after the peak PETM. Enhanced climate extremes at mid-latitudes might have been a direct response to the massive CO2 input in the ocean atmosphere system at the Paleocene-Eocene transition, and may have had a primary role in restoring the Earth system to steady state.

  15. Flecainide attenuates rate adaptation of ventricular repolarization in guinea-pig heart.

    PubMed

    Osadchii, Oleg E

    2016-01-01

    Flecainide is class Ic antiarrhythmic agent that was found to increase the risk of sudden cardiac death. Arrhythmic responses to flecainide could be precipitated by exercise, suggesting a role played by inappropriate rate adaptation of ventricular repolarization. This study therefore examined flecainide effect on adaptation of the QT interval and ventricular action potential duration (APD) to abrupt reductions of the cardiac cycle length. ECG and ventricular epicardial and endocardial monophasic APD were recorded in isolated, perfused guinea-pig heart preparations upon a sustained cardiac acceleration (rapid pacing for 30 s), and following a single perturbation of the cycle length evoked by extrasystolic stimulation. Sustained increase in heart rate was associated with progressive bi-exponential shortening of the QT interval and APD. Flecainide prolonged ventricular repolarization, delayed its rate adaptation, and decreased the amplitude of QT interval and APD shortening upon rapid cardiac pacing. During extrasystolic stimulation, flecainide attenuated APD shortening in premature ventricular beats, with effect being greater upon using a longer basic drive cycle length (S1-S1=550 ms versus S1-S1=300 ms). Flecainide-induced arrhythmia may be partly accounted for by attenuated adaptation of ventricular repolarization to sudden changes in cardiac cycle length provoked by transient tachycardia or ectopic beats.

  16. Risperidone prolongs cardiac repolarization by blocking the rapid component of the delayed rectifier potassium current.

    PubMed

    Drolet, Benoit; Yang, Tao; Daleau, Pascal; Roden, Dan M; Turgeon, Jacques

    2003-06-01

    Cases of QT prolongation and sudden death have been reported with risperidone, a neuroleptic agent increasingly prescribed worldwide. Although hypokalemia was present in some of these events, we hypothesized that risperidone may have unsuspected electrophysiologic effects predisposing patients to proarrhythmia. In six isolated guinea pig hearts, risperidone elicited prolongation of cardiac repolarization: action potential duration increased from a baseline value of 128 ms +/- 5 to 147 ms +/- 5 (15%) with risperidone 1 microM during pacing at 250-ms cycle length, whereas the increase was only 10%, from 101 ms +/- 2 to 111 ms +/- 4, with pacing at a cycle length of 150 ms. In human ether-a-go-go (HERG)-transfected Chinese hamster ovary cells (n = 16), risperidone caused concentration-dependent block of the rapid component (I(Kr)) of the delayed rectifier potassium current with an IC(50) for tail block of 261 nM. Risperidone did not block I(Ks). Risperidone exerts cardiac electrophysiologic effects similar to those of Class III antiarrhythmic drugs. These effects are observed at clinically relevant concentrations. Because risperidone is metabolized primarily by CYP2D6, these actions likely enhance risk for risperidone-related QT prolongation and proarrhythmia in specific patient subsets (e.g., poor metabolizers and those taking interacting drugs).

  17. Water Intelligence and the Cyber-Infrastructure Revolution

    NASA Astrophysics Data System (ADS)

    Cline, D. W.

    2015-12-01

    As an intrinsic factor in national security, the global economy, food and energy production, and human and ecological health, fresh water resources are increasingly being considered by an ever-widening array of stakeholders. The U.S. intelligence community has identified water as a key factor in the Nation's security risk profile. Water industries are growing rapidly, and seek to revolutionize the role of water in the global economy, making water an economic value rather than a limitation on operations. Recent increased focus on the complex interrelationships and interdependencies between water, food, and energy signal a renewed effort to move towards integrated water resource management. Throughout all of this, hydrologic extremes continue to wreak havoc on communities and regions around the world, in some cases threatening long-term economic stability. This increased attention on water coincides with the "second IT revolution" of cyber-infrastructure (CI). The CI concept is a convergence of technology, data, applications and human resources, all coalescing into a tightly integrated global grid of computing, information, networking and sensor resources, and ultimately serving as an engine of change for collaboration, education and scientific discovery and innovation. In the water arena, we have unprecedented opportunities to apply the CI concept to help address complex water challenges and shape the future world of water resources - on both science and socio-economic application fronts. Providing actionable local "water intelligence" nationally or globally is now becoming feasible through high-performance computing, data technologies, and advanced hydrologic modeling. Further development on all of these fronts appears likely and will help advance this much-needed capability. Lagging behind are water observation systems, especially in situ networks, which need significant innovation to keep pace with and help fuel rapid advancements in water intelligence.

  18. An infrared optical pacing system for high-throughput screening of cardiac electrophysiology in human cardiomyocytes (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    McPheeters, Matt T.; Wang, Yves T.; Laurita, Kenneth R.; Jenkins, Michael W.

    2017-02-01

    Cardiomyocytes derived from human induced pluripotent stem cells (hiPS-HCM) have the potential to provide individualized therapies for patients and to test drug candidates for cardiac toxicity. In order for hiPS-CM to be useful for such applications, there is a need for high-throughput technology to rapidly assess cardiac electrophysiology parameters. Here, we designed and tested a fully contactless optical mapping (OM) and optical pacing (OP) system capable of imaging and point stimulation of hiPS-CM in small wells. OM allowed us to characterize cardiac electrophysiological parameters (conduction velocity, action potential duration, etc.) using voltage-sensitive dyes with high temporal and spatial resolution over the entire well. To improve OM signal-to-noise ratio, we tested a new voltage-sensitive dye (Fluovolt) for accuracy and phototoxicity. Stimulation is essential because most electrophysiological parameters are rate dependent; however, traditional methods utilizing electrical stimulation is difficult in small wells. To overcome this limitation, we utilized OP (λ = 1464 nm) to precisely control heart rate with spatial precision without the addition of exogenous agents. We optimized OP parameters (e.g., well size, pulse width, spot size) to achieve robust pacing and minimize the threshold radiant exposure. Finally, we tested system sensitivity using Flecainide, a drug with well described action on multiple electrophysiological properties.

  19. Percutaneous Transvenous Mitral Annuloplasty (PTMA) with the Viking device reduces pacing-induced mitral regurgitation.

    PubMed

    Kimblad, Per Ola; Harnek, Jan; Roijer, Anders; Meurling, Carl; Brandt, Johan; Solem, Jan Otto

    2005-11-01

    The new percutaneous mitral annuloplasty Viking device was evaluated in surviving sheep with pacing-induced mitral regurgitation. Twenty sheep were subjected to rapid ventricular pacing for one to three months, leading to cardiomyopathy and mitral regurgitation. Device implantation could be successfully performed in 11 of these animals after pacemaker treatment for 64+/-7 days. The device-related procedure time was 12+/-2 min. The mean follow-up time was 58+/-8 days after implantation of the device. Mitral annulus septo-lateral diameter was significantly reduced after insertion of the device, from 35+/-1 mm before implantation to 30+/-1 mm at the final follow up intracardiac echocardiography (P = 0.0097). The degree of mitral regurgitation (on a scale from 0 to 4) was 2.6+/-0.2 before device implantation and decreased to 0.8+/-0.2 after treatment (P = 0.0039), and the vena contracta was reduced from 7+/-0.4 mm to 3+/-0.8 mm (P = 0.0019). Angiography showed no signs of impairment of the coronary arteries. No thrombosis was observed. These results indicate that the septo-lateral diameter of the mitral annulus, and the degree of experimentally induced mitral regurgitation, can be significantly reduced with a percutaneous catheter technique in surviving sheep.

  20. A distinctive subpopulation of medial septal slow-firing neurons promote hippocampal activation and theta oscillations

    PubMed Central

    Lin, Shih-Chieh; Nicolelis, Miguel A. L.

    2011-01-01

    The medial septum-vertical limb of the diagonal band of Broca (MSvDB) is important for normal hippocampal functions and theta oscillations. Although many previous studies have focused on understanding how MSVDB neurons fire rhythmic bursts to pace hippocampal theta oscillations, a significant portion of MSVDB neurons are slow-firing and thus do not pace theta oscillations. The function of these MSVDB neurons, especially their role in modulating hippocampal activity, remains unknown. We recorded MSVDB neuronal ensembles in behaving rats, and identified a distinct physiologically homogeneous subpopulation of slow-firing neurons (overall firing <4 Hz) that shared three features: 1) much higher firing rate during rapid eye movement sleep than during slow-wave (SW) sleep; 2) temporary activation associated with transient arousals during SW sleep; 3) brief responses (latency 15∼30 ms) to auditory stimuli. Analysis of the fine temporal relationship of their spiking and theta oscillations showed that unlike the theta-pacing neurons, the firing of these “pro-arousal” neurons follows theta oscillations. However, their activity precedes short-term increases in hippocampal oscillation power in the theta and gamma range lasting for a few seconds. Together, these results suggest that these pro-arousal slow-firing MSvDB neurons may function collectively to promote hippocampal activation. PMID:21865435

  1. Optimal pacing modes after cardiac transplantation: is synchronisation of recipient and donor atria beneficial?

    PubMed Central

    Parry, Gareth; Malbut, Katie; Dark, John H; Bexton, Rodney S

    1992-01-01

    Objective—To investigate the response of the transplanted heart to different pacing modes and to synchronisation of the recipient and donor atria in terms of cardiac output at rest. Design—Doppler derived cardiac output measurements at three pacing rates (90/min, 110/min and 130/min) in five pacing modes: right ventricular pacing, donor atrial pacing, recipient-donor synchronous pacing, donor atrial-ventricular sequential pacing, and synchronous recipient-donor atrial-ventricular sequential pacing. Patients—11 healthy cardiac transplant recipients with three pairs of epicardial leads inserted at transplantation. Results—Donor atrial pacing (+11% overall) and donor atrial-ventricular sequential pacing (+8% overall) were significantly better than right ventricular pacing (p < 0·001) at all pacing rates. Synchronised pacing of recipient and donor atrial segments did not confer additional benefit in either atrial or atrial-ventricular sequential modes of pacing in terms of cardiac output at rest at these fixed rates. Conclusions—Atrial pacing or atrial-ventricular sequential pacing appear to be appropriate modes in cardiac transplant recipients. Synchronisation of recipient and donor atrial segments in this study produced no additional benefit. Chronotropic competence in these patients may, however, result in improved exercise capacity and deserves further investigation. PMID:1389737

  2. Optimizing implantable cardioverter-defibrillator treatment of rapid ventricular tachycardia: antitachycardia pacing therapy during charging.

    PubMed

    Schoels, Wolfgang; Steinhaus, David; Johnson, W Ben; O'hara, Gilles; Schwab, Joerg O; Jenniskens, Inge; Degroot, Paul J; Tang, Feng; Helmling, Erhard

    2007-07-01

    Previous studies in implantable cardioverter-defibrillator (ICD) patients demonstrated the efficacy and safety of antitachycardia pacing (ATP) for rapid ventricular tachycardias (VT). To prevent shock delay in case of ATP failure, a new feature (ATP during charging) was developed to deliver ATP for rapid VT while charging for shock. The purpose of this study was to determine the efficacy and safety of this new feature. In a prospective, nonrandomized trial, patients with standard ICD indication received an EnTrust ICD. VT and ventricular fibrillation (VF) episodes were reviewed for appropriate detection, ATP success, rhythm acceleration, and related symptoms. In 421 implanted patients, 116 VF episodes occurred in 37 patients. Eighty-four (72%) episodes received ATP during or before charging. ATP prevented a shock in 58 (69%) of 84 episodes in 15 patients. ATP stopped significantly more monomorphic (77%) than polymorphic VTs (44%, P = .05). Five (6%) episodes accelerated after ATP but were terminated by the backup shock(s). No symptoms were related to ATP during charging. In four patients, 38 charges were saved by delivering ATP before charging. Of 98 induced VF episodes, 28% were successfully terminated by ATP versus 69% for spontaneous episodes (P <.01). Most VTs detected in the VF zone can be painlessly terminated by ATP delivered during charging, with a low risk of acceleration or symptoms. ATP before charging allows delivery of two ATP attempts before shock in the same time that would otherwise be required to deliver only one ATP plus a shock. It also offers potential battery energy savings.

  3. An interhemispheric tropical sea level seesaw due to El Niño Taimasa

    NASA Astrophysics Data System (ADS)

    Widlansky, M. J.; Timmermann, A.; McGregor, S.; Stuecker, M. F.; Cai, W.

    2013-12-01

    During strong El Niño events, sea level drops around some tropical western Pacific islands by up to 20-30 cm. Such extreme events (referred to as ';taimasa' in Samoa) expose shallow reefs, thereby damaging associated coastal ecosystems and contributing to the formation of ';flat topped coral heads' often referred to as microatolls. We show that during the termination of strong El Niño events, a southward movement of weak trade winds and development of an anomalous anticyclone in the Philippine Sea force an interhemispheric sea level seesaw in the tropical Pacific which enhances and prolongs extreme low sea levels in the southwestern Pacific. Spectral features, in addition to wind forced linear shallow water ocean model experiments, identify an interaction between El Niño and the annual cycle as the main cause of these sea level anomalies. Given the well established seasonal prediction skill for El Niño events and their seasonally paced termination, our analysis suggests that long-duration extreme sea level drops may also be highly predictable.

  4. Kinetics of Materials at Extreme Conditions: Understanding the Time Dependent Approach to Equilibrium at MaRIE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kraus, R. G.; Mcnabb, D.; Kumar, M.

    The National Nuclear Security Agency has recently recognized that a long-term need exists to establish a stronger scientific basis for the assessment and qualification of materials and manufacturing processes for the nuclear stockpile and other national security applications. These materials may have undergone substantial changes with age, or may represent new materials that are being introduced because of difficulties associated with reusing or recreating materials used in original stockpile components. Also, with advancements in manufacturing methods, the NNSA anticipates opportunities for an enhanced range of control over fabricated components, an enhanced pace of materials development, and enhanced functionality. The developmentmore » of qualification standards for these new materials will require the ability to understand and control material characteristics that affect both mechanical and dynamic performance. A unique aspect for NNSA is that the performance requirements for materials are often set by system hydrodynamics, and these materials must perform in extreme environments and loading conditions. Thus, the scientific motivation is to understand “Matter-Radiation Interactions in Extremes (MaRIE).”« less

  5. Extreme Temperature Exceedances Change more Rapidly Under Future Warming in Regions of non-Gaussian Short Temperature Distribution Tails

    NASA Astrophysics Data System (ADS)

    Loikith, P. C.; Neelin, J. D.; Meyerson, J.

    2017-12-01

    Regions of shorter-than-Gaussian warm and cold side temperature distribution tails are shown to occur in spatially coherent patterns in the current climate. Under such conditions, warming may be manifested in more complex ways than if the underlying distribution were close to Gaussian. For example, under a uniform warm shift, the simplest prototype for future warming, a location with a short warm side tail would experience a greater increase in extreme warm exceedances compared to if the distribution were Gaussian. Similarly, for a location with a short cold side tail, a uniform warm shift would result in a rapid decrease in extreme cold exceedances. Both scenarios carry major societal and environmental implications including but not limited to negative impacts on human and ecosystem health, agriculture, and the economy. It is therefore important for climate models to be able to realistically reproduce short tails in simulations of historical climate in order to boost confidence in projections of future temperature extremes. Overall, climate models contributing to the fifth phase of the Coupled Model Intercomparison Project capture many of the principal observed regions of short tails. This suggests the underlying dynamics and physics occur on scales resolved by the models, and helps build confidence in model projections of extremes. Furthermore, most GCMs show more rapid changes in exceedances of extreme temperature thresholds in regions of short tails. Results therefore suggest that the shape of the tails of the underlying temperature distribution is an indicator of how rapidly a location will experience changes to extreme temperature occurrence under future warming.

  6. Address by Jacques Delors, Chairman of the International Commission on Education for the Twenty-First Century, General Conference of UNESCO (27th, Paris, France, November 2, 1993).

    ERIC Educational Resources Information Center

    Delors, Jacques

    In this speech to the members of the general conference of UNESCO, the chairman of the International Commission on Education for the Twenty-First Century describes the progress of the Commission's work. The chairman discusses education and the challenges of the world as it enters the 21st century. Changes mentioned include the rapid pace of…

  7. Implications of the U.S. War on Terrorism for U.S.-China Policy: A Strategic Window

    DTIC Science & Technology

    2002-04-12

    network of supporting ministerial forums: including trade ministers, foreign ministers, finance ministers, ministers of the environment, and...especially the banks, so it can finance efficiently a rapidly growing economy.113 The pace of reform is ultimately constrained by the economy�s...Thailand’s beaches and California’s Disneyland . Over one million Chinese traveled abroad on pleasure trips in 1998, a record number despite the

  8. Presentation Time Concerning System-Paced Multimedia Instructions and the Superiority of Learner Pacing

    ERIC Educational Resources Information Center

    Stiller, Klaus D.; Petzold, Kirstin; Zinnbauer, Peter

    2011-01-01

    The superiority of learner-paced over system-paced instructions was demonstrated in multiple experiments. In these experiments, the system-paced presentations were highly speeded, causing cognitive overload, while the learner-paced instructions allowed adjustments of the presentational flow to the learner's needs by pacing facilities, mostly…

  9. Effectiveness of Occupational Therapy Interventions for Lower-Extremity Musculoskeletal Disorders: A Systematic Review.

    PubMed

    Dorsey, Julie; Bradshaw, Michelle

    Lower-extremity (LE) musculoskeletal disorders (MSDs) can have a major impact on the ability to carry out daily activities. The effectiveness of interventions must be examined to enable occupational therapy practitioners to deliver the most appropriate services. This systematic review examined the literature published between 1995 and July 2014 that investigated the effectiveness of occupational therapy interventions for LE MSDs. Forty-three articles met the criteria and were reviewed. Occupational therapy interventions varied on the basis of population subgroup: hip fracture, LE joint replacement, LE amputation or limb loss, and nonsurgical osteoarthritis and pain. The results indicate an overall strong role for occupational therapy in treating clients with LE MSDs. Activity pacing is an effective intervention for nonsurgical LE MSDs, and multidisciplinary rehabilitation is effective for LE joint replacement and amputation. Further research on specific occupational therapy interventions in this important area is needed. Copyright © 2017 by the American Occupational Therapy Association, Inc.

  10. Immune defense and reproductive pace of life in Peromyscus mice.

    PubMed

    Martin, Lynn B; Weil, Zachary M; Nelson, Randy J

    2007-10-01

    Immune activity is variable within and among vertebrates despite the potentially large fitness costs of pathogens to their hosts. From the perspective of life history theory, immunological variability may be the consequence of counterbalancing investments in immune defense against other expensive physiological processes, namely, reproduction. In the present study, we tested the hypothesis that immune defense among captive-bred, disease-free Peromyscus mice would be influenced by their reproductive life history strategies. Specifically, we expected that small species that reproduce prolifically and mature rapidly (i.e., fast pace of life) would favor inexpensive, nonspecific immune defenses to promote reproductive proclivity. Alternatively, we expected that large species that mature slowly and invest modestly in reproduction over multiple events (i.e., slow pace of life) would favor developmentally expensive, specific immune defenses and avoid cheap, nonspecific ones because such defenses are predisposed to self-damage. We found that species exhibited either strong ability to kill (gram-negative) bacteria, a developmentally inexpensive defense, or strong ability to produce antibodies against a novel protein, a developmentally expensive defense, but not both. Cell-mediated inflammation also varied significantly among species, but in a unique fashion relative to bacteria killing or antibody production; wound healing was comparatively similar among species. These results indicate that Peromyscus species use immune strategies that are constrained to a dominant axis, but this axis is not determined solely by reproductive pace of life. Further comparisons, ideally with broader phylogenetic coverage, could identify what ecological and evolutionary forces produce the pattern we detected. Importantly, our study indicates that species may not be differentially immunocompetent; rather, they use unique defense strategies to prevent infection.

  11. Changes in left ventricular repolarization and ion channel currents following a transient rate increase superimposed on bradycardia in anesthetized dogs.

    PubMed

    Rubart, M; Lopshire, J C; Fineberg, N S; Zipes, D P

    2000-06-01

    We previously demonstrated in dogs that a transient rate increase superimposed on bradycardia causes prolongation of ventricular refractoriness that persists for hours after resumption of bradycardia. In this study, we examined changes in membrane currents that are associated with this phenomenon. The whole cell, patch clamp technique was used to record transmembrane voltages and currents, respectively, in single mid-myocardial left ventricular myocytes from dogs with 1 week of complete AV block; dogs either underwent 1 hour of left ventricular pacing at 120 beats/min or did not undergo pacing. Pacing significantly heightened mean phase 1 and peak plateau amplitudes by approximately 6 and approximately 3 mV, respectively (P < 0.02), and prolonged action potential duration at 90% repolarization from 235+/-8 msec to 278+/-8 msec (1 Hz; P = 0.02). Rapid pacing-induced changes in transmembrane ionic currents included (1) a more pronounced cumulative inactivation of the 4-aminopyridine-sensitive transient outward K+ current, Ito, over the range of physiologic frequencies, resulting from a approximately 30% decrease in the population of quickly reactivating channels; (2) increases in peak density of L-type Ca2+ currents, I(Ca.L), by 15% to 35 % between +10 and +60 mV; and (3) increases in peak density of the Ca2+-activated chloride current, I(Cl.Ca), by 30% to 120% between +30 and +50 mV. Frequency-dependent reduction in Ito combined with enhanced I(Ca.L) causes an increase in net inward current that may be responsible for the observed changes in ventricular repolarization. This augmentation of net cation influx is partially antagonized by an increase in outward I(Ca.Cl).

  12. Early change in thermal perception is not a driver of anticipatory exercise pacing in the heat.

    PubMed

    Barwood, Martin James; Corbett, Jo; White, Danny; James, Jason

    2012-10-01

    Initial power output declines significantly during exercise in hot conditions on attaining a rapid increase in skin temperature when exercise commences. It is unclear whether this initial reduced power is mediated consciously, through thermal perceptual cues, or is a subconscious process. The authors tested the hypothesis that improved thermal perception (feeling cooler and more comfortable) in the absence of a change in thermal state (ie, similar deep-body and skin temperatures between spray conditions) would alter pacing and 40 km cycling time trial (TT) performance. Eleven trained participants (mean (SD): age 30 (8.1) years; height 1.78 (0.06) m; mass 76.0 (8.3) kg) completed three 40 km cycling TTs in standardised conditions (32°C, 50% RH) with thermal perception altered prior to exercise by application of cold-receptor-activating menthol spray (MENTHOL SPRAY), in contrast to a separate control spray (CONTROL SPRAY) and no spray control (CON). Thermal perception, perceived exertion, thermal responses and cycling TT performance were measured. MENTHOL SPRAY induced feelings of coolness and improved thermal comfort before and during exercise. Skin temperature profile at the start of exercise was similar between sprays (CON-SPRAY 33.3 (1.1)°C and MENTHOL SPRAY 33.4 (0.4)°C, but different to CON 34.5 (0.5)°C), but there was no difference in the pacing strategy adopted. There was no performance benefit using MENTHOL SPRAY; cycling TT completion time for CON is 71.58 (6.21) min, for CON-SPRAY is 70.94 (6.06) min and for MENTHOL SPRAY is 71.04 (5.47) min. The hypothesis is rejected. Thermal perception is not a primary driver of early pacing during 40 km cycling TT in hot conditions in trained participants.

  13. Tachycardia-Induced J-Wave Changes in Patients With and Without Idiopathic Ventricular Fibrillation.

    PubMed

    Aizawa, Yoshiyasu; Takatsuki, Seiji; Nishiyama, Takahiko; Kimura, Takehiro; Kohsaka, Shun; Kaneko, Yoshiaki; Inden, Yasuya; Takahashi, Naohiko; Nagase, Satoshi; Aizawa, Yoshifusa; Fukuda, Keichi

    2017-07-01

    To know the underlying mechanisms of J waves, the response to atrial pacing was studied in patients with idiopathic ventricular fibrillation (IVF) and patients with non-IVF. In 8 patients with IVF, the J-wave amplitude was measured before, during, and after atrial pacing. All patients had episodes of ventricular fibrillation without structural heart disease. The responses of J waves were compared with those of the 17 non-IVF control subjects who revealed J waves but no history of cardiac arrest and underwent electrophysiological study. The IVF patients were younger than the non-IVF patients (28±10 versus 52±14 years, respectively; P =0.002) and had larger J waves with more extensive distribution. J waves decreased from 0.35±0.26 to 0.22±0.23 mV ( P =0.025) when the RR intervals were shortened from 782±88 to 573±162 ms ( P =0.001). A decrease (≥0.05 mV) in the J-wave amplitude was observed in 6 of the 8 patients. In addition, 1 patient showed a distinct reduction of J waves in the unipolar epicardial leads. In contrast, J waves were augmented in the 17 non-IVF subjects from 0.27±0.09 to 0.38±0.10 mV ( P <0.001): augmented in 9 and unchanged in the 8 subjects. The different response patterns of J waves to rapid pacing suggest different mechanisms: early repolarization in IVF patients and conduction delay in non-IVF patients. The response to atrial pacing was different between the IVF and non-IVF patients, which suggests the presence of different mechanisms for the genesis of J waves. © 2017 American Heart Association, Inc.

  14. A Fully Implantable Pacemaker for the Mouse: From Battery to Wireless Power

    PubMed Central

    Zellmer, Erik R.; Weinheimer, Carla J.; MacEwan, Matthew R.; Cui, Sophia X.; Nerbonne, Jeanne M.; Efimov, Igor R.

    2013-01-01

    Animal models have become a popular platform for the investigation of the molecular and systemic mechanisms of pathological cardiovascular physiology. Chronic pacing studies with implantable pacemakers in large animals have led to useful models of heart failure and atrial fibrillation. Unfortunately, molecular and genetic studies in these large animal models are often prohibitively expensive or not available. Conversely, the mouse is an excellent species for studying molecular mechanisms of cardiovascular disease through genetic engineering. However, the large size of available pacemakers does not lend itself to chronic pacing in mice. Here, we present the design for a novel, fully implantable wireless-powered pacemaker for mice capable of long-term (>30 days) pacing. This design is compared to a traditional battery-powered pacemaker to demonstrate critical advantages achieved through wireless inductive power transfer and control. Battery-powered and wireless-powered pacemakers were fabricated from standard electronic components in our laboratory. Mice (n = 24) were implanted with endocardial, battery-powered devices (n = 14) and epicardial, wireless-powered devices (n = 10). Wireless-powered devices were associated with reduced implant mortality and more reliable device function compared to battery-powered devices. Eight of 14 (57.1%) mice implanted with battery-powered pacemakers died following device implantation compared to 1 of 10 (10%) mice implanted with wireless-powered pacemakers. Moreover, device function was achieved for 30 days with the wireless-powered device compared to 6 days with the battery-powered device. The wireless-powered pacemaker system presented herein will allow electrophysiology studies in numerous genetically engineered mouse models as well as rapid pacing-induced heart failure and atrial arrhythmia in mice. PMID:24194832

  15. Loss of atrial contractility is primary cause of atrial dilatation during first days of atrial fibrillation.

    PubMed

    Schotten, Ulrich; de Haan, Sunniva; Neuberger, Hans-Ruprecht; Eijsbouts, Sabine; Blaauw, Yuri; Tieleman, Robert; Allessie, Maurits

    2004-11-01

    Atrial fibrillation (AF) induces a progressive dilatation of the atria which in turn might promote the arrhythmia. The mechanism of atrial dilatation during AF is not known. To test the hypothesis that loss of atrial contractile function is a primary cause of atrial dilatation during the first days of AF, eight goats were chronically instrumented with epicardial electrodes, a pressure transducer in the right atrium, and piezoelectric crystals to measure right atrial diameter. AF was induced with the use of repetitive burst pacing. Atrial contractility was assessed during sinus rhythm, atrial pacing (160-, 300-, and 400-ms cycle length), and electrically induced AF. The compliance of the fibrillating right atrium was measured during unloading the atria with diuretics and loading with 1 liter of saline. All measurements were repeated after 6, 12, and 24 h of AF and then once a day during the first 5 days of AF. Recovery of the observed changes after spontaneous cardioversion was also studied. After 5 days of AF, atrial contractility during sinus rhythm or slow atrial pacing was greatly reduced. During rapid pacing (160 ms) or AF, the amplitude of the atrial pressure waves had declined to 20% of control. The compliance of the fibrillating atria increased twofold, whereas the right atrial pressure was unchanged. As a result, the mean right atrial diameter increased by approximately 12%. All changes were reversible within 3 days of sinus rhythm. We conclude that atrial dilatation during the first days of AF is due to an increase in atrial compliance caused by loss of atrial contractility during AF. Atrial compliance and size are restored when atrial contractility recovers after cardioversion of AF.

  16. Abnormalities in intracellular calcium regulation and contractile function in myocardium from dogs with pacing-induced heart failure

    NASA Technical Reports Server (NTRS)

    Perreault, C. L.; Shannon, R. P.; Komamura, K.; Vatner, S. F.; Morgan, J. P.

    1992-01-01

    24 d of rapid ventricular pacing induced dilated cardiomyopathy with both systolic and diastolic dysfunction in conscious, chronically instrumented dogs. We studied mechanical properties and intracellular calcium (Ca2+i) transients of trabeculae carneae isolated from 15 control dogs (n = 32) and 11 dogs with pacing-induced cardiac failure (n = 26). Muscles were stretched to maximum length at 30 degrees C and stimulated at 0.33 Hz; a subset (n = 17 control, n = 17 myopathic) was loaded with the [Ca2+]i indicator aequorin. Peak tension was depressed in the myopathic muscles, even in the presence of maximally effective (i.e., 16 mM) [Ca2+] in the perfusate. However, peak [Ca2+]i was similar (0.80 +/- 0.13 vs. 0.71 +/- 0.05 microM; [Ca2+]o = 2.5 mM), suggesting that a decrease in Cai2+ availability was not responsible for the decreased contractility. The time for decline from the peak of the Cai2+ transient was prolonged in the myopathic group, which correlated with prolongation of isometric contraction and relaxation. However, similar end-diastolic [Ca2+]i was achieved in both groups (0.29 +/- 0.05 vs. 0.31 +/- 0.02 microM), indicating that Cai2+ homeostasis can be maintained in myopathic hearts. The inotropic response of the myopathic muscles to milrinone was depressed compared with the controls. However, when cAMP production was stimulated by pretreatment with forskolin, the response of the myopathic muscles to milrinone was improved. Our findings provide direct evidence that abnormal [Ca2+]i handling is an important cause of contractile dysfunction in dogs with pacing-induced heart failure and suggest that deficient production of cAMP may be an important cause of these changes in excitation-contraction coupling.

  17. Regulation of the endothelin-1 transmembrane signaling pathway: the potential role of agonist-induced desensitization in the coronary artery of the rapid ventricular pacing-overdrive dog model of heart failure.

    PubMed

    Calderone, A; Rouleau, J L; de Champlain, J; Bélichard, P; Stewart, D J

    1993-08-01

    This study examined the potential role of ET-1 and the contribution of protein kinase C (PKC) in the desensitization of the ET-1 transmembrane signaling pathway in the left circumflex coronary artery (CCA) of a dog model of congestive heart failure (CHF). In the CCA of the rapid ventricular pacing-overdrive dog model of CHF, elevated plasma endothelin levels were associated with a decrease in the basal accumulation of inositol phosphates and ET-1 mediated activation of phosphatidylinositol (PI) turnover (P < 0.05). To assess whether elevated plasma ET-1 levels may have contributed to the diminished ET-1 responsiveness in the heart failure dogs, ET-1 generation of inositol phosphates was measured following a one hour pretreatment of normal coronary artery rings with 0.1 nM ET-1. As compared to non-treated rings, ET-1 pretreatment resulted in a 33% decrease of ET-1 (10 nM) production of inositol phosphates. To evaluate the role of PKC in this process, normal coronary rings pretreated for a period of one hour with the phorbol ester, phorbol 12-myristate 13-acetate (PMA, 1 microM), resulted in a similar attenuation (36%) of ET-1 production of inositol phosphates. In the presence of the protein kinase C inhibitor staurosporine, both the agonist and phorbol ester induced decreases in ET-1 mediated PI turnover were reversed. Staurosporine even potentiated (75%) ET-1 induced PI turnover despite ET-1 and PMA pretreatments. These results suggest that agonist-induced desensitization of ET-1 mediated PI turnover can occur and is at least one of the possible mechanisms contributing to the desensitization of the ET-1 transmembrane signaling pathway in the pacing-overdrive model of heart failure in the dog.

  18. RATT: Rapid Annotation Transfer Tool

    PubMed Central

    Otto, Thomas D.; Dillon, Gary P.; Degrave, Wim S.; Berriman, Matthew

    2011-01-01

    Second-generation sequencing technologies have made large-scale sequencing projects commonplace. However, making use of these datasets often requires gene function to be ascribed genome wide. Although tool development has kept pace with the changes in sequence production, for tasks such as mapping, de novo assembly or visualization, genome annotation remains a challenge. We have developed a method to rapidly provide accurate annotation for new genomes using previously annotated genomes as a reference. The method, implemented in a tool called RATT (Rapid Annotation Transfer Tool), transfers annotations from a high-quality reference to a new genome on the basis of conserved synteny. We demonstrate that a Mycobacterium tuberculosis genome or a single 2.5 Mb chromosome from a malaria parasite can be annotated in less than five minutes with only modest computational resources. RATT is available at http://ratt.sourceforge.net. PMID:21306991

  19. Why is the rapid burster different from all other galactic-bulge X-ray sources?

    NASA Astrophysics Data System (ADS)

    Milgrom, M.

    1987-01-01

    It is suggested that the rapid X-ray burster exhibits unique behavior because it contains a neutron star whose stellar radius is smaller than the minimum radius of a circular orbit that is stable according to general relativity. The star accretes from a disk that extends down to the last stable orbit. In this state, the disk is unstable against a rapid fall and accretion of its innermost part onto the star. The sudden dumping of mass gives rise to a burst of X-rays. The disk then heals, refilling the inner region at a pace that is dictated mainly by the global accretion rate, in order to ready itself for the next burst. In all other galactic-bulge-type sources, the neutron star is larger than the last stable orbit.

  20. Environmental stress and adaptational responses: consequences for human health outcomes.

    PubMed

    Garruto, Ralph M; Little, Michael A; Weitz, Charles A

    2004-12-01

    With the dramatic pace of modernization of the world's population, human adaptation as a theoretical construct and paradigm will likely become a focal scientific issue involving scientists from many disciplinary areas during the 21st Century. Macro and micro environments are in rapid flux and human populations are exposed to rapid change. The concept of adaptation, at least in the field of biological anthropology and human biology, will likely remain tied to evolutionary processes and concepts of selection and fitness. In this paper, we discuss the theoretical constructs of adaptation and adaptability and select three current examples from our ongoing research that involve studies of adaptation and evolutionary processes in modernizing populations in different locations worldwide.

  1. Long term effect of a modified hydrodynamic at a lagoon inlet on the salt marsh ability to keep pace with sea level rise.

    NASA Astrophysics Data System (ADS)

    Carniello, L.; Nordio, G.; D'Alpaos, A.; Silvestri, S.

    2016-12-01

    In a context of global increase of mean sea level, the fate of salt marshes relates to their ability of keeping pace with relative sea level rise (SLR) and depends on the external sediment supply and organic soil production. Detecting the vertical sinking of salt marshes is a difficult task being the process characterized by time scales of tens to hundreds of years. Thanks to the availability of historical maps of the Venice lagoon, we reconstructed the reduction of salt mash areas that occurred in the northern part of the lagoon in the last two centuries. In this period, anthropic interventions played a crucial role in promoting the disappearance of vast marsh surfaces in the inner lagoon, while the marshes closer to the inlet remained fairly stable. Using a 2D numerical model we investigated the hydrodynamic behavior of different ancient lagoon configurations analyzing the effect of i) the construction of the jetties at the Lido inlet in 1882-1892 and ii) the removal of reed barriers that protected a fish farm area in the same period. Our results show that the deepening of the inlet induced by the construction of the jetties had a positive feedback on the vertical accretion of the salt marshes close to the inlet by lowering the local mean sea level and increasing the tidal amplitude. This effect contrasted the eustatic SLR for more than 30 years, allowing these marshes to increase their height with respect to the local mean sea level. On the contrary, the salt marshes far from the inlet could not take the same rapid advantage of this effect due to tidal wave dissipation characterizing tide propagation in shallow basins. Elevation of inner marshes is low due to the small tidal excursion, making these marshes extremely vulnerable to changes in sediment supply and SLR. We show that the removal of reed barriers used by ancient Venetians to create fish farms in the inner lagoon may have reduced the sediments available to the marshes thus contributing to their drowning.

  2. Temporary atrial epicardial pacing as prophylaxis against atrial fibrillation after heart surgery: a meta-analysis.

    PubMed

    Daoud, Emile G; Snow, Rick; Hummel, John D; Kalbfleisch, Steven J; Weiss, Raul; Augostini, Ralph

    2003-02-01

    Recent studies have reported the use of temporary epicardial atrial pacing as prophylaxis for postoperative atrial fibrillation (AF). The aim of this study was to assess the effect of pacing therapies for prevention of postoperative AF using meta-analysis. Using a computerized MEDLINE search, eight pacing prophylaxis trials with 776 patients were included in the meta-analysis. Trials compared control patients to patients randomized to right atrial, left atrial, or biatrial pacing used in conjunction with either fixed high-rate pacing or overdrive pacing. Overdrive biatrial pacing (OR 2.6, CI 1.4-4.8), overdrive right atrial pacing (OR 1.8, CI 1.1-2.7), and fixed high-rate biatrial pacing (OR 2.5, CI 1.3-5.1) demonstrated a significant antiarrhythmic effect for prevention of AF after open heart surgery. Furthermore, studies investigating overdrive left atrial pacing and fixed high-rate right atrial pacing have been underpowered to assess efficacy. Biatrial overdrive and fixed high-rate pacing and right atrial fixed high-rate pacing reduced the risk of new-onset AF after open heart surgery, and the relative risk reduction is approximately 2.5-fold. These results imply that various pacing algorithms are useful as a nonpharmacologic method to prevent postoperative AF.

  3. 42 CFR 460.60 - PACE organizational structure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false PACE organizational structure. 460.60 Section 460.60 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ELDERLY (PACE) PACE Administrative Requirements § 460.60 PACE organizational structure. (a) A PACE...

  4. Physiologic pacing: new modalities and pacing sites.

    PubMed

    Padeletti, Luigi; Lieberman, Randy; Valsecchi, Sergio; Hettrick, Douglas A

    2006-12-01

    Right ventricular (RV) apical pacing impairs left ventricular function by inducing dys-synchronous contraction and relaxation. Chronic RV apical pacing is associated with an increased risk of atrial fibrillation, morbidity, and even mortality. These observations have raised questions regarding the appropriate pacing mode and site, leading to the introduction of algorithms and new pacing modes to reduce the ventricular pacing burden in dual chamber devices, and a shift of the pacing site away from the RV apex. However, further investigations are required to assess the long-term results of pacing from alternative sites in the right ventricle, because long-term results so far are equivocal. The potential benefit of prophylactic biventricular, mono-chamber left ventricular, and bifocal RV pacing should be explored in selected patients with a narrow QRS complex, especially those with impaired left ventricular function. His bundle pacing is a promising and evolving technique that requires improvements in lead technology.

  5. Reduced Physical Fidelity Training Device Concepts for Army Maintenance Training.

    DTIC Science & Technology

    1978-09-01

    rapidly. In addition, the task- orientet ’ nature of self-pacee training is creating a need f~r even more equipment to support this newer method of...substitution for AET devices might be considered, to specify the conceptual form for such RPF devices, and to provide proceduial guidance for the future ...describe the RPF alternatives that can be considered for future development by the Army, and to set forth a procedure for their evaluation. The

  6. Adapting Digital Libraries to Continual Evolution

    NASA Technical Reports Server (NTRS)

    Barkstrom, Bruce R.; Finch, Melinda; Ferebee, Michelle; Mackey, Calvin

    2002-01-01

    In this paper, we describe five investment streams (data storage infrastructure, knowledge management, data production control, data transport and security, and personnel skill mix) that need to be balanced against short-term operating demands in order to maximize the probability of long-term viability of a digital library. Because of the rapid pace of information technology change, a digital library cannot be a static institution. Rather, it has to become a flexible organization adapted to continuous evolution of its infrastructure.

  7. Evolutionary considerations in the development of chronic pelvic pain.

    PubMed

    Jarrell, John; Arendt-Nielsen, Lars

    2016-08-01

    Chronic pelvic pain is common among women of reproductive age and is associated with significant morbidity and comorbidities. In this Viewpoint, we explore the evolutionary cause of pelvic pain and summarize evidence that supports a menstruation-related evolutionary cause of chronic visceral pelvic pain: (1) lifetime menstruation has increased; (2) severe dysmenorrhea is common in the chronic pelvic pain population, particularly among those with pain sensitization; and (3) a potential biological mechanism can be identified. Thus, chronic pelvic pain may arise from the mismatch between the slow pace of biological evolution in our bodies and the relatively rapid pace of cultural changes that have resulted in increased menstrual frequency due to earlier menarche, later mortality, and lower fecundity. One possible mechanism that explains the development of persistent pain from repeated episodes of intermittent pain is hyperalgesic priming, a physiological process defined as a long-lasting latent hyperresponsiveness of nociceptors to inflammatory mediators after an inflammatory or neuropathic insult. The repetitive severely painful menstrual episodes may play such a role. From an evolutionary perspective the relatively rapid increase in lifetime menstruation experience in contemporary society may contribute to a mismatch between lifetime menstruation and the physiological pain processes, leading to a maladaptive state of chronic visceral pelvic pain. Our current physiology does not conform to current human needs. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Plasma cleaning of nanoparticles from EUV mask materials by electrostatics

    NASA Astrophysics Data System (ADS)

    Lytle, W. M.; Raju, R.; Shin, H.; Das, C.; Neumann, M. J.; Ruzic, D. N.

    2008-03-01

    Particle contamination on surfaces used in extreme ultraviolet (EUV) mask blank deposition, mask fabrication, and patterned mask handling must be avoided since the contamination can create significant distortions and loss of reflectivity. Particles on the order of 10nm are problematic during MLM mirror fabrication, since the introduced defects disrupt the local Bragg planes. The most serious problem is the accumulation of particles on surfaces of patterned blanks during EUV light exposure, since > 25nm particles will be printed without an out-of-focus pellicle. Particle contaminants are also a problem with direct imprint processes since defects are printed every time. Plasma Assisted Cleaning by Electrostatics (PACE) works by utilizing a helicon plasma as well as a pulsed DC substrate bias to charge particle and repel them electrostatically from the surface. Removal of this nature is a dry cleaning method and removes contamination perpendicular from the surface instead of rolling or sweeping the particles off the surface, a benefit when cleaning patterned surfaces where contamination can be rolled or trapped between features. Also, an entire mask can be cleaned at once since the plasma can cover the entire surface, thus there is no need to focus in on an area to clean. Sophisticated particle contamination detection system utilizing high power laser called DEFCON is developed to analyze the particle removal after PACE cleaning process. PACE has shown greater than 90 % particle removal efficiencies for 30 to 220 nm PSL particles on ruthenium capped quartz. Removal results for silicon surfaces and quartz surfaces show similar removal efficiencies. Results of cleaning 80 nm PSL spheres from silicon substrates will be shown.

  9. 42 CFR 460.6 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Basis... enrolled in a PACE program. PACE stands for programs of all-inclusive care for the elderly. PACE center is... care for the elderly that is operated by an approved PACE organization and that provides comprehensive...

  10. 42 CFR 460.6 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Basis... enrolled in a PACE program. PACE stands for programs of all-inclusive care for the elderly. PACE center is... care for the elderly that is operated by an approved PACE organization and that provides comprehensive...

  11. 42 CFR 460.180 - Medicare payment to PACE organizations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Medicare payment to PACE organizations. 460.180... FOR THE ELDERLY (PACE) Payment § 460.180 Medicare payment to PACE organizations. (a) Principle of payment. Under a PACE program agreement, CMS makes a prospective monthly payment to the PACE organization...

  12. Electrophysiological determinants of hypokalaemia-induced arrhythmogenicity in the guinea-pig heart.

    PubMed

    Osadchii, O E; Olesen, S P

    2009-12-01

    Hypokalaemia is an independent risk factor contributing to arrhythmic death in cardiac patients. In the present study, we explored the mechanisms of hypokalaemia-induced tachyarrhythmias by measuring ventricular refractoriness, spatial repolarization gradients, and ventricular conduction time in isolated, perfused guinea-pig heart preparations. Epicardial and endocardial monophasic action potentials from distinct left ventricular (LV) and right ventricular (RV) recording sites were monitored simultaneously with volume-conducted electrocardiogram (ECG) during steady-state pacing and following a premature extrastimulus application at progressively reducing coupling stimulation intervals in normokalaemic and hypokalaemic conditions. Hypokalaemic perfusion (2.5 mm K(+) for 30 min) markedly increased the inducibility of tachyarrhythmias by programmed ventricular stimulation and rapid pacing, prolonged ventricular repolarization and shortened LV epicardial and endocardial effective refractory periods, thereby increasing the critical interval for LV re-excitation. Hypokalaemia increased the RV-to-LV transepicardial repolarization gradients but had no effect on transmural dispersion of APD(90) and refractoriness across the LV wall. As determined by local activation time recordings, the LV-to-RV transepicardial conduction and the LV transmural (epicardial-to-endocardial) conduction were slowed in hypokalaemic heart preparations. This change was attributed to depressed diastolic excitability as evidenced by increased ventricular pacing thresholds. These findings suggest that hypokalaemia-induced arrhythmogenicity is attributed to shortened LV refractoriness, increased critical intervals for LV re-excitation, amplified RV-to-LV transepicardial repolarization gradients and slowed ventricular conduction in the guinea-pig heart.

  13. Dispersal will limit ability of mammals to track climate change in the Western Hemisphere

    PubMed Central

    Schloss, Carrie A.; Nuñez, Tristan A.; Lawler, Joshua J.

    2012-01-01

    As they have in response to past climatic changes, many species will shift their distributions in response to modern climate change. However, due to the unprecedented rapidity of projected climatic changes, some species may not be able to move their ranges fast enough to track shifts in suitable climates and associated habitats. Here, we investigate the ability of 493 mammals to keep pace with projected climatic changes in the Western Hemisphere. We modeled the velocities at which species will likely need to move to keep pace with projected changes in suitable climates. We compared these velocities with the velocities at which species are able to move as a function of dispersal distances and dispersal frequencies. Across the Western Hemisphere, on average, 9.2% of mammals at a given location will likely be unable to keep pace with climate change. In some places, up to 39% of mammals may be unable to track shifts in suitable climates. Eighty-seven percent of mammalian species are expected to experience reductions in range size and 20% of these range reductions will likely be due to limited dispersal abilities as opposed to reductions in the area of suitable climate. Because climate change will likely outpace the response capacity of many mammals, mammalian vulnerability to climate change may be more extensive than previously anticipated. PMID:22586104

  14. Determinants of the development of mitral regurgitation in pacing-induced heart failure.

    PubMed

    Takagaki, Masami; McCarthy, Patrick M; Goormastic, Marlene; Ochiai, Yoshie; Doi, Kazuyoshi; Kopcak, Michael W; Tabata, Tomotsugu; Cardon, Lisa A; Thomas, James D; Fukamachi, Kiyotaka

    2003-01-01

    The pacing-induced heart failure model provides an opportunity to assess the structural and functional determinants of mitral regurgitation (MR) in dilated cardiomyopathy. This study aimed to evaluate MR to better understand the multitude of factors contributing to its development. Heart failure was induced by rapid ventricular pacing (230 beats/min) in 40 mongrel dogs. Left ventricular (LV) size and MR were evaluated echocardiographically. LV contractility was analyzed using a conductance catheter. MR increased to mild in 12 animals (regurgitant orifice area, 0.06+/-0.05 cm(2)), moderate in 15 (0.14+/-0.07 cm(2)), and severe in 13 (0.34+/-0.16 cm(2)). The grade of MR had an inverse relationships with E(max) (the slope of the end-systolic pressure-volume relationship, p<0.01) and dE/dt (the slope of the maximum rate of change of pressure-end-diastolic volume [V(ED)] relationship, p<0.01) and positive relationships with V(ED) and end-diastolic cross-sectional areas and lengths (p<0.05) by univariate analysis. The dE/dt had an independently significant (p<0.01) relationship by multivariable logistic regression. Many factors influence the development of MR and because of its similarity to the clinical situation, this model can be used to investigate MR and heart failure, as well as new surgical therapies.

  15. Surface electromyographic mapping of the orbicularis oculi muscle for real-time blink detection.

    PubMed

    Frigerio, Alice; Cavallari, Paolo; Frigeni, Marta; Pedrocchi, Alessandra; Sarasola, Andrea; Ferrante, Simona

    2014-01-01

    Facial paralysis is a life-altering condition that significantly impairs function, appearance, and communication. Facial rehabilitation via closed-loop pacing represents a potential but as yet theoretical approach to reanimation. A first critical step toward closed-loop facial pacing in cases of unilateral paralysis is the detection of healthy movements to use as a trigger to prosthetically elicit automatic artificial movements on the contralateral side of the face. To test and to maximize the performance of an electromyography (EMG)-based blink detection system for applications in closed-loop facial pacing. Blinking was detected across the periocular region by means of multichannel surface EMG at an academic neuroengineering and medical robotics laboratory among 15 healthy volunteers. Real-time blink detection was accomplished by mapping the surface of the orbicularis oculi muscle on one side of the face with a multichannel surface EMG. The biosignal from each channel was independently processed; custom software registered a blink when an amplitude-based or slope-based suprathreshold activity was detected. The experiments were performed when participants were relaxed and during the production of particular orofacial movements. An F1 score metric was used to analyze software performance in detecting blinks. The maximal software performance was achieved when a blink was recorded from the superomedial orbit quadrant. At this recording location, the median F1 scores were 0.89 during spontaneous blinking, 0.82 when chewing gum, 0.80 when raising the eyebrows, and 0.70 when smiling. The overall performance of blink detection was significantly better at the superomedial quadrant (F1 score, 0.75) than at the traditionally used inferolateral quadrant (F1 score, 0.40) (P < .05). Electromyographic recording represents an accurate tool to detect spontaneous blinks as part of closed-loop facial pacing systems. The early detection of blink activity may allow real-time pacing via rapid triggering of contralateral muscles. Moreover, an EMG detection system can be integrated in external devices and in implanted neuroprostheses. A potential downside to this approach involves cross talk from adjacent muscles, which can be notably reduced by recording from the superomedial quadrant of the orbicularis oculi muscle and by applying proper signal processing. NA.

  16. Sea ice and millennial-scale climate variability in the Nordic seas 90 kyr ago to present

    PubMed Central

    Hoff, Ulrike; Rasmussen, Tine L.; Stein, Ruediger; Ezat, Mohamed M.; Fahl, Kirsten

    2016-01-01

    In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial-scale climatic events (Dansgaard/Oeschger events) using the sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species in a record from the southeast Norwegian Sea. We demonstrate that expansion and retreat of sea ice varies consistently in pace with the rapid climate changes 90 kyr ago to present. Sea ice retreats abruptly at the start of warm interstadials, but spreads rapidly during cooling phases of the interstadials and becomes near perennial and perennial during cold stadials and Heinrich events, respectively. Low-salinity surface water and the sea ice edge spreads to the Greenland–Scotland Ridge, and during the largest Heinrich events, probably far into the Atlantic Ocean. PMID:27456826

  17. Sea ice and millennial-scale climate variability in the Nordic seas 90 kyr ago to present.

    PubMed

    Hoff, Ulrike; Rasmussen, Tine L; Stein, Ruediger; Ezat, Mohamed M; Fahl, Kirsten

    2016-07-26

    In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial-scale climatic events (Dansgaard/Oeschger events) using the sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species in a record from the southeast Norwegian Sea. We demonstrate that expansion and retreat of sea ice varies consistently in pace with the rapid climate changes 90 kyr ago to present. Sea ice retreats abruptly at the start of warm interstadials, but spreads rapidly during cooling phases of the interstadials and becomes near perennial and perennial during cold stadials and Heinrich events, respectively. Low-salinity surface water and the sea ice edge spreads to the Greenland-Scotland Ridge, and during the largest Heinrich events, probably far into the Atlantic Ocean.

  18. An Efficient, Rapid, and Recyclable System for CRISPR-Mediated Genome Editing in Candida albicans.

    PubMed

    Nguyen, Namkha; Quail, Morgan M F; Hernday, Aaron D

    2017-01-01

    Candida albicans is the most common fungal pathogen of humans. Historically, molecular genetic analysis of this important pathogen has been hampered by the lack of stable plasmids or meiotic cell division, limited selectable markers, and inefficient methods for generating gene knockouts. The recent development of clustered regularly interspaced short palindromic repeat(s) (CRISPR)-based tools for use with C. albicans has opened the door to more efficient genome editing; however, previously reported systems have specific limitations. We report the development of an optimized CRISPR-based genome editing system for use with C. albicans . Our system is highly efficient, does not require molecular cloning, does not leave permanent markers in the genome, and supports rapid, precise genome editing in C. albicans . We also demonstrate the utility of our system for generating two independent homozygous gene knockouts in a single transformation and present a method for generating homozygous wild-type gene addbacks at the native locus. Furthermore, each step of our protocol is compatible with high-throughput strain engineering approaches, thus opening the door to the generation of a complete C. albicans gene knockout library. IMPORTANCE Candida albicans is the major fungal pathogen of humans and is the subject of intense biomedical and discovery research. Until recently, the pace of research in this field has been hampered by the lack of efficient methods for genome editing. We report the development of a highly efficient and flexible genome editing system for use with C. albicans . This system improves upon previously published C. albicans CRISPR systems and enables rapid, precise genome editing without the use of permanent markers. This new tool kit promises to expedite the pace of research on this important fungal pathogen.

  19. Air Pollution Monitoring and Use of Nanotechnology Based Solid State Gas Sensors in Greater Cairo Area, Egypt

    NASA Astrophysics Data System (ADS)

    Ramadan, A. B. A.

    Air pollution is a serious problem in thickly populated and industrialized areas in Egypt, especially in greater Cairo area. Economic growth and industrialization are proceeding at a rapid pace, accompanied by increasing emissions of air polluting sources. Furthermore, though the variety and quantities of polluting sources have increased dramatically, the development of a suitable method for monitoring the pollution causing sources has not followed at the same pace. Environmental impacts of air pollutants have impact on public health, vegetation, material deterioration etc. To prevent or minimize the damage caused by atmospheric pollution, suitable monitoring systems are urgently needed that can rapidly and reliably detect and quantify polluting sources for monitoring by regulating authorities in order to prevent further deterioration of the current pollution levels. Consequently, it is important that the current real-time air quality monitoring system, controlled by the Egyptian Environmental Affairs Agency (EEAA), should be adapted or extended to aid in alleviating this problem. Nanotechnology has been applied to several industrial and domestic fields, for example, applications for gas monitoring systems, gas leak detectors in factories, fire and toxic gas detectors, ventilation control, breath alcohol detectors, and the like. Here we report an application example of studying air quality monitoring based on nanotechnology `solid state gas sensors'. So as to carry out air pollution monitoring over an extensive area, a combination of ground measurements through inexpensive sensors and wireless GIS will be used for this purpose. This portable device, comprising solid state gas sensors integrated to a Personal Digital Assistant (PDA) linked through Bluetooth communication tools and Global Positioning System (GPS), will allow rapid dissemination of information on pollution levels at multiple sites simultaneously.

  20. Direct His bundle pacing post AVN ablation.

    PubMed

    Lakshmanadoss, Umashankar; Aggarwal, Ashim; Huang, David T; Daubert, James P; Shah, Abrar

    2009-08-01

    Atrioventricular nodal (AVN) ablation with concomitant pacemaker implantation is one of the strategies that reduce symptoms in patients with atrial fibrillation (AF). However, the long-term adverse effects of right ventricular (RV) apical pacing have led to the search for alternating sites of pacing. Biventricular pacing produces a significant improvement in functional capacity over RV pacing in patients undergoing AVN ablation. Another alternative site for pacing is direct His bundle to reduce the adverse outcome of RV pacing. Here, we present a case of direct His bundle pacing using steerable lead delivery system in a patient with symptomatic paroxysmal AF with concurrent AVN ablation.

  1. 42 CFR 460.34 - Duration of PACE program agreement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.34 Duration of PACE program agreement. An agreement is...

  2. 42 CFR 460.34 - Duration of PACE program agreement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.34 Duration of PACE program agreement. An agreement is...

  3. Structural damage to periodontal tissues at varying rate of anesthetic injection.

    PubMed

    Sarapultseva, Maria; Sarapultsev, Alexey; Medvedeva, Svetlana; Danilova, Irina

    2018-04-01

    Incorrect administration of an anesthetic during local anesthesia is one of the most important causes of pain symptoms in patients scheduled for dental procedures. The current study assessed the severity of damage to periodontal tissue following different rates of anesthetic administration. The research was conducted on 50 outbred male rats with a body mass of 180-240 g. The anesthetic used was 1% articaine. The results showed that administration of the anesthetic at a rapid pace caused structural damage to the periodontal tissue. Further, signs of impaired microcirculation were noted at all rates of administration. Biochemical studies demonstrated changes in the level of glucose and enzymes with the rapid introduction of the anesthetic, indicating severe systemic stress response of the body. Injection of local anesthetic at any rate of introduction induces vascular congestion in the microcirculatory bloodstream and exudative reactions. Rapid introduction of an anesthetic causes progression of structural changes in the gingival tissue.

  4. An efficient and rapid influenza gene cloning strategy for reverse genetics system.

    PubMed

    Shao, Hongxia; Fan, Zhonglei; Wan, Zhimin; Tian, Xiaoyan; Chen, Hongjun; Perez, Daniel R; Qin, Aijian; Ye, Jianqiang

    2015-09-15

    Influenza reverse genetics plays vital roles in understanding influenza molecular characteristics and vaccine development. However, current influenza reverse genetics heavily depends on restriction enzyme and ligation for gene cloning. The traditional cloning process of influenza eight fragments for virus rescuing generally requires considerable work. To simplify and increase the pace of gene cloning for influenza reverse genetics system, we developed a rapid restriction enzyme-free ExnaseTM II-based in vitro recombination approach for influenza gene cloning. We used this strategy rapidly and successfully to clone influenza eight genes both from viruses PR8 and H9N2 for virus rescuing. Our data demonstrate that the strategy developed here can accelerate the process of influenza gene cloning into reverse genetics system, and shows high potential for applications in both influenza basic and applied research. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. A novel brain-computer interface based on the rapid serial visual presentation paradigm.

    PubMed

    Acqualagna, Laura; Treder, Matthias Sebastian; Schreuder, Martijn; Blankertz, Benjamin

    2010-01-01

    Most present-day visual brain computer interfaces (BCIs) suffer from the fact that they rely on eye movements, are slow-paced, or feature a small vocabulary. As a potential remedy, we explored a novel BCI paradigm consisting of a central rapid serial visual presentation (RSVP) of the stimuli. It has a large vocabulary and realizes a BCI system based on covert non-spatial selective visual attention. In an offline study, eight participants were presented sequences of rapid bursts of symbols. Two different speeds and two different color conditions were investigated. Robust early visual and P300 components were elicited time-locked to the presentation of the target. Offline classification revealed a mean accuracy of up to 90% for selecting the correct symbol out of 30 possibilities. The results suggest that RSVP-BCI is a promising new paradigm, also for patients with oculomotor impairments.

  6. Bachmann's Bundle Pacing not Only Improves Interatrial Conduction but Also Reduces the Need for Ventricular Pacing.

    PubMed

    Sławuta, Agnieszka; Kliś, Magdalena; Skoczyński, Przemysław; Bańkowski, Tomasz; Moszczyńska-Stulin, Joanna; Gajek, Jacek

    2016-01-01

    Patients treated for sick sinus syndrome may have interatrial conduction disorder leading to atrial fibrillation. This study was aimed to assess the influence of the atrial pacing site on interatrial and atrioventricular conduction as well as the percentage of ventricular pacing in patients with sick sinus syndrome implanted with atrioventricular pacemaker. The study population: 96 patients (58 females, 38 males) aged 74.1 ± 11.8 years were divided in two groups: Group 1 (n = 44) with right atrial appendage pacing and group 2 (n = 52) with Bachmann's area pacing. We assessed the differences in atrioventricular conduction in sinus rhythm and atrial 60 and 90 bpm pacing, P-wave duration and percentage of ventricular pacing. No differences in baseline P-wave duration in sinus rhythm between the groups (102.4 ± 17 ms vs. 104.1 ± 26 ms, p = ns.) were noted. Atrial pacing 60 bpm resulted in longer P-wave in group 1 vs. group 2 (138.3 ± 21 vs. 106.1 ± 15 ms, p < 0.01). The differences between atrioventricular conduction time during sinus rhythm and atrial pacing at 60 and 90 bpm were significantly longer in patients with right atrial appendage vs. Bachmann's pacing (44.1 ± 17 vs. 9.2 ± 7 ms p < 0.01 and 69.2 ± 31 vs. 21.4 ± 12 ms p < 0.05, respectively). The percentage of ventricular pacing was higher in group 1 (21 vs. 4%, p < 0.01). Bachmann's bundle pacing decreases interatrial and atrioventricular conduction delay. Moreover, the frequency-dependent atrioventricular conduction lengthening is much less pronounced during Bachmann's bundle pacing. Right atrial appendage pacing in sick sinus syndrome patients promotes a higher percentage of ventricular pacing.

  7. 42 CFR 460.32 - Content and terms of PACE program agreement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.32 Content and terms of PACE program agreement. (a...

  8. 42 CFR 460.90 - PACE benefits under Medicare and Medicaid.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Services § 460.90 PACE benefits under Medicare and Medicaid. If a Medicare...

  9. Multi-Leu PACE4 Inhibitor Retention within Cells Is PACE4 Dependent and a Prerequisite for Antiproliferative Activity

    PubMed Central

    Ly, Kévin; Levesque, Christine; Kwiatkowska, Anna; Ait-Mohand, Samia; Desjardins, Roxane; Guérin, Brigitte; Day, Robert

    2015-01-01

    The overexpression as well as the critical implication of the proprotein convertase PACE4 in prostate cancer progression has been previously reported and supported the development of peptide inhibitors. The multi-Leu peptide, a PACE4-specific inhibitor, was further generated and its capability to be uptaken by tumor xenograft was demonstrated with regard to its PACE4 expression status. To investigate whether the uptake of this inhibitor was directly dependent of PACE4 levels, uptake and efflux from cancer cells were evaluated and correlations were established with PACE4 contents on both wild type and PACE4-knockdown cell lines. PACE4-knockdown associated growth deficiencies were established on the knockdown HepG2, Huh7, and HT1080 cells as well as the antiproliferative effects of the multi-Leu peptide supporting the growth capabilities of PACE4 in cancer cells. PMID:26114115

  10. Computational data sciences for assessment and prediction of climate extremes

    NASA Astrophysics Data System (ADS)

    Ganguly, A. R.

    2011-12-01

    Climate extremes may be defined inclusively as severe weather events or large shifts in global or regional weather patterns which may be caused or exacerbated by natural climate variability or climate change. This area of research arguably represents one of the largest knowledge-gaps in climate science which is relevant for informing resource managers and policy makers. While physics-based climate models are essential in view of non-stationary and nonlinear dynamical processes, their current pace of uncertainty reduction may not be adequate for urgent stakeholder needs. The structure of the models may in some cases preclude reduction of uncertainty for critical processes at scales or for the extremes of interest. On the other hand, methods based on complex networks, extreme value statistics, machine learning, and space-time data mining, have demonstrated significant promise to improve scientific understanding and generate enhanced predictions. When combined with conceptual process understanding at multiple spatiotemporal scales and designed to handle massive data, interdisciplinary data science methods and algorithms may complement or supplement physics-based models. Specific examples from the prior literature and our ongoing work suggests how data-guided improvements may be possible, for example, in the context of ocean meteorology, climate oscillators, teleconnections, and atmospheric process understanding, which in turn can improve projections of regional climate, precipitation extremes and tropical cyclones in an useful and interpretable fashion. A community-wide effort is motivated to develop and adapt computational data science tools for translating climate model simulations to information relevant for adaptation and policy, as well as for improving our scientific understanding of climate extremes from both observed and model-simulated data.

  11. Health policy in Asia and the Pacific: Navigating local needs and global challenges

    PubMed Central

    Lee, Kelley

    2014-01-01

    Asia and the Pacific are undergoing a remarkable economic transformation which is occurring at an exceptional pace. There is clear evidence of an equally rapid epidemiological transition in the region. This paper sets out the policy challenges of building healthy societies in the context of rapid economic change. The region’s location at the crossroads of contemporary globalization, resulting in intensified population mobility, large-scale trade and investment, and pressures to take collective action on shared problems, adds to the complexity of this task. The paper argues that health is integral to building stable and sustainable societies, and that there are opportunities to develop more holistic approaches that bring together hitherto separate policy spheres. PMID:24592312

  12. Influence of automatic frequent pace-timing adjustments on effective left ventricular pacing during cardiac resynchronization therapy.

    PubMed

    Varma, Niraj; Stadler, Robert W; Ghosh, Subham; Kloppe, Axel

    2017-05-01

    Cardiac resynchronization therapy (CRT) requires effective left ventricular (LV) pacing (i.e. sufficient energy and appropriate timing to capture). The AdaptivCRT™ (aCRT) algorithm serves to maintain ventricular fusion during LV or biventricular pacing. This function was tested by comparing the morphological consistency of ventricular depolarizations and percentage effective LV pacing in CRT patients randomized to aCRT vs. echo-optimization. Continuous recordings (≥20 h) of unipolar LV electrograms from aCRT (n = 38) and echo-optimized patients (n = 22) were analysed. Morphological consistency was determined by the correlation coefficient between each beat and a template beat. Effective LV pacing of paced beats was assessed by algorithmic analysis of negative initial EGM deflection in each evoked response. The %CRT pacing delivered, %effective LV pacing (i.e. % of paced beats with effective LV pacing), and overall %effective CRT (i.e. product of %CRT pacing and %effective LV pacing) were compared between aCRT and echo-optimized patients. Demographics were similar between groups. The mean correlation coefficient between individual beats and template was greater for aCRT (0.96 ± 0.03 vs. 0.91 ± 0.13, P = 0.07). Although %CRT pacing was similar for aCRT and echo-optimized (median 97.4 vs. 98.6%, P = 0.14), %effective LV pacing was larger for aCRT [99.6%, (99.1%, 99.9%) vs. 94.3%, (24.3%, 99.8%), P=0.03]. For aCRT vs. echo-optimized groups, the proportions of patients with ≥90% effective LV pacing was 92 vs. 55% (P = 0.002), and with ≥90% effective CRT was 79 vs. 45%, respectively (P = 0.018). AdaptivCRT™ significantly increased effective LV pacing over echo-optimized CRT. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  13. INFLUENCE OF AEROSPACE MEDICINE ACHIEVEMENTS ON THE DEVELOPMENT OF SPORT MEDICINE METHODOLOGY.

    PubMed

    R Yashina, E R; Kurashvili, V A; Turzin, P S

    Modern technologies of aerospace medicine develop at rapid pace pulling on its orbit all spheres of the human activity, including sport. Innovations play a major role in the progress of sport medicine areas related to the biomedical support of precontest training. Overview of the most important aerospace medicine achievements and their methodical implications for sport medicine is presented. Discussion is devoted to how the aerospace medicine technologies can raise effectiveness of the biomedical support to different sectors of sport and fitness.

  14. Sensor Webs to Constellations

    NASA Astrophysics Data System (ADS)

    Cole, M.

    2017-12-01

    Advanced technology plays a key role in enabling future Earth-observing missions needed for global monitoring and climate research. Rapid progress over the past decade and anticipated for the coming decades have diminished the size of some satellites while increasing the amount of data and required pace of integration and analysis. Sensor web developments provide correlations to constellations of smallsats. Reviewing current advances in sensor webs and requirements for constellations will improve planning, operations, and data management for future architectures of multiple satellites with a common mission goal.

  15. General Motors' R&D: Managing Innovation Globally

    NASA Astrophysics Data System (ADS)

    Taub, Alan

    2006-03-01

    The rapid pace of technology development and the globalization of the automobile industry are major forces driving General Motors to devise new ways to innovate faster and more efficiently. In response, GM has developed a global R&D network that has transformed GM's research and development organization from a U.S.-based enterprise to one that is over 30 percent leveraged with collaboration in 16 countries. This talk will focus on the challenges faced as well as the lessons learned and best practices developed in building this network.

  16. Clinical Neurogenetics: Amyotrophic Lateral Sclerosis

    PubMed Central

    Harms, Matthew B.; Baloh, Robert H.

    2013-01-01

    Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease, about which our understanding is expanding rapidly as its genetic causes are uncovered. The pace of new gene discovery over the last 5 years has accelerated, providing new insights into the pathogenesis of disease and highlighting biological pathways for target for therapeutic development. This article reviews our current understanding of the heritability of ALS, provides an overview of each of the major ALS genes, highlighting their phenotypic characteristics and frequencies as a guide for clinicians evaluating patients with ALS. PMID:24176417

  17. The U.S. Navy in Operation Overlord Under the Command of Rear Admiral Alan G. Kirk

    DTIC Science & Technology

    1994-05-19

    assault on the beaches. 14. SUBJECT TERMS 15. NUMBER OF PAGES Operation Overlord, COSSAC, Admiral Alan G. Kirk, U.S. Navy 16. PRICE CODE 17. SECUriLY ...Allies’ smal2 but growing forces. 5 Although reluctant to confront the German Army in France, Brooke admitted that reasons existed to take the Qamble; the...After Kirk took command of TF122, the pace of American landing craft and personnel arrival into Britain rapidly increased. Kirk told Stark that the

  18. The effect of workstation and task variables on forces applied during simulated meat cutting.

    PubMed

    McGorry, Raymond W; Dempsey, Patrick G; O'Brien, Niall V

    2004-12-01

    The purpose of the study was to investigate factors related to force and postural exposure during a simulated meat cutting task. The hypothesis was that workstation, tool and task variables would affect the dependent kinetic variables of gripping force, cutting moment and the dependent kinematic variables of elbow elevation and wrist angular displacement in the flexion/extension and radial/ulnar deviation planes. To evaluate this hypothesis a 3 x 3 x 2 x 2 x 2 (surface orientation by surface height by blade angle by cut complexity by work pace) within-subject factorial design was conducted with 12 participants. The results indicated that the variables can act and interact to modify the kinematics and kinetics of a cutting task. Participants used greater grip force and cutting moment when working at a pace based on productivity. The interactions of the work surface height and orientation indicated that the use of an adjustable workstation could minimize wrist deviation from neutral and improve shoulder posture during cutting operations. Angling the knife blade also interacted with workstation variables to improve wrist and upper extremity posture, but this benefit must be weighed against the potential for small increases in force exposure.

  19. Conservation at a slow pace: terrestrial gastropods facing fast-changing climate

    PubMed Central

    Ansart, Armelle

    2017-01-01

    Abstract The climate is changing rapidly, and terrestrial ectotherms are expected to be particularly vulnerable to changes in temperature and water regime, but also to an increase in extreme weather events in temperate regions. Physiological responses of terrestrial gastropods to climate change are poorly studied. This is surprising, because they are of biodiversity significance among litter-dwelling species, playing important roles in ecosystem function, with numerous species being listed as endangered and requiring efficient conservation management. Through a summary of our ecophysiological work on snail and slug species, we gained some insights into physiological and behavioural responses to climate change that we can organize into the following four threat categories. (i) Winter temperature and snow cover. Terrestrial gastropods use different strategies to survive sub-zero temperatures in buffered refuges, such as the litter or the soil. Absence of the insulating snow cover exposes species to high variability in temperature. The extent of specific cold tolerance might influence the potential of local extinction, but also of invasion. (ii) Drought and high temperature. Physiological responses involve high-cost processes that protect against heat and dehydration. Some species decrease activity periods, thereby reducing foraging and reproduction time. Related costs and physiological limits are expected to increase mortality. (iii) Extreme events. Although some terrestrial gastropod communities can have a good resilience to fire, storms and flooding, an increase in the frequency of those events might lead to community impoverishment. (iv) Habitat loss and fragmentation. Given that terrestrial gastropods are poorly mobile, landscape alteration generally results in an increased risk of local extinction, but responses are highly variable between species, requiring studies at the population level. There is a great need for studies involving non-invasive methods on the plasticity of physiological and behavioural responses and the ability for local adaptation, considering the spatiotemporally heterogeneous climatic landscape, to allow efficient management of ecosystems and conservation of biodiversity. PMID:28852510

  20. Conservation at a slow pace: terrestrial gastropods facing fast-changing climate.

    PubMed

    Nicolai, Annegret; Ansart, Armelle

    2017-01-01

    The climate is changing rapidly, and terrestrial ectotherms are expected to be particularly vulnerable to changes in temperature and water regime, but also to an increase in extreme weather events in temperate regions. Physiological responses of terrestrial gastropods to climate change are poorly studied. This is surprising, because they are of biodiversity significance among litter-dwelling species, playing important roles in ecosystem function, with numerous species being listed as endangered and requiring efficient conservation management. Through a summary of our ecophysiological work on snail and slug species, we gained some insights into physiological and behavioural responses to climate change that we can organize into the following four threat categories. (i) Winter temperature and snow cover. Terrestrial gastropods use different strategies to survive sub-zero temperatures in buffered refuges, such as the litter or the soil. Absence of the insulating snow cover exposes species to high variability in temperature. The extent of specific cold tolerance might influence the potential of local extinction, but also of invasion. (ii) Drought and high temperature. Physiological responses involve high-cost processes that protect against heat and dehydration. Some species decrease activity periods, thereby reducing foraging and reproduction time. Related costs and physiological limits are expected to increase mortality. (iii) Extreme events. Although some terrestrial gastropod communities can have a good resilience to fire, storms and flooding, an increase in the frequency of those events might lead to community impoverishment. (iv) Habitat loss and fragmentation. Given that terrestrial gastropods are poorly mobile, landscape alteration generally results in an increased risk of local extinction, but responses are highly variable between species, requiring studies at the population level. There is a great need for studies involving non-invasive methods on the plasticity of physiological and behavioural responses and the ability for local adaptation, considering the spatiotemporally heterogeneous climatic landscape, to allow efficient management of ecosystems and conservation of biodiversity.

  1. Influence of Pacing by Periodic Auditory Stimuli on Movement Continuation: Comparison with Self-regulated Periodic Movement

    PubMed Central

    Ito, Masanori; Kado, Naoki; Suzuki, Toshiaki; Ando, Hiroshi

    2013-01-01

    [Purpose] The purpose of this study was to investigate the influence of external pacing with periodic auditory stimuli on the control of periodic movement. [Subjects and Methods] Eighteen healthy subjects performed self-paced, synchronization-continuation, and syncopation-continuation tapping. Inter-onset intervals were 1,000, 2,000 and 5,000 ms. The variability of inter-tap intervals was compared between the different pacing conditions and between self-paced tapping and each continuation phase. [Results] There were no significant differences in the mean and standard deviation of the inter-tap interval between pacing conditions. For the 1,000 and 5,000 ms tasks, there were significant differences in the mean inter-tap interval following auditory pacing compared with self-pacing. For the 2,000 ms syncopation condition and 5,000 ms task, there were significant differences from self-pacing in the standard deviation of the inter-tap interval following auditory pacing. [Conclusion] These results suggest that the accuracy of periodic movement with intervals of 1,000 and 5,000 ms can be improved by the use of auditory pacing. However, the consistency of periodic movement is mainly dependent on the inherent skill of the individual; thus, improvement of consistency based on pacing is unlikely. PMID:24259932

  2. Indications for permanent pacing and pacing mode prescription from 1989 to 2006. Experience of a single academic centre in Northern Greece.

    PubMed

    Styliadis, Ioannis H; Mantziari, Aggeliki P; Gouzoumas, Nikolaos I; Vassilikos, Vasilios P; Paraskevaidis, Stelios A; Mochlas, Sotirios T; Boufidou, Amalia I; Parcharidis, Georgios E

    2008-01-01

    Indications for pacing and pacing mode prescription have changed in the past decades following advances in pacemaker technology. The aim of the present study was to evaluate changes in indications for pacing and pacing modes during the years 1989-2006 in a single academic pacemaker centre in Northern Greece. Archives of permanent pacemaker implantation procedures were studied retrospectively and data from all implants, first or replacements, were retrieved. Data from 2078 procedures were found, 78.7% of which were first implantations. Patients were 54% male with mean age 72.5 years. Main indications for pacing were atrioventricular block (AVB, 45.7%), sick sinus syndrome (SSS, 32.8%), and atrial fibrillation (12.1%). Almost half (48.9%) of the AVB cases were complete AVB, while the most common types of SSS were tachy-brady syndrome (44.1%) and asystole (27.1%). Rare indications for pacing were carotid sinus syndrome (5.0%), heart failure (3.3%) and hypertrophic obstructive cardiomyopathy (1.0%). The two most frequently used pacing modes were VVI (38.5%) and DDD (25.8%). However, pacing modes have changed greatly over the years, with a marked increase in dual-chamber pacing after 1997 and a preference for rate responsive units after 2002. Biventricular systems were also used in selected patients with heart failure from 2002 on. Indications for pacing and pacing mode prescription in our centre are similar to other pacemaker registries and reflect the global trend in pacing for mimicking the physiological activity of the heart and for addressing problems other than symptomatic bradycardia.

  3. Functional characteristics of left ventricular synchronization via right ventricular outflow-tract pacing detected by two-dimensional strain echocardiography.

    PubMed

    Hirayama, Yasutaka; Kawamura, Yuichiro; Sato, Nobuyuki; Saito, Tatsuya; Tanaka, Hideichi; Saijo, Yasuaki; Kikuchi, Kenjiro; Ohori, Katsumi; Hasebe, Naoyuki

    2017-02-01

    Recently, due to the detrimental effects on the ventricular function associated with right ventricular apical (RVA) pacing, right ventricular septal (RVS) pacing has become the preferred pacing method. However, the term RVS pacing refers to both right ventricular outflow-tract (RVOT) and mid-septal (RVMS) pacing, leading to a misinterpretation of the results of clinical studies. The purpose of this study, therefore, was to elucidate the functional differences of RVA, RVOT, and RVMS pacing in patients with atrioventricular block. We compared the QRS duration, global longitudinal strain (GLS), and left ventricular (LV) synchronization parameters at the three pacing sites in 47 patients. The peak systolic strain (PSS) time delay between the earliest and latest segments among the 18 LV segments and standard deviation (SD) of the time to the PSS were also calculated for the 18 LV segments at each pacing site using two-dimensional (2D) strain echocardiography. RVMS pacing was associated with a significantly shorter QRS duration compared with RVA and RVOT pacing (154.4±21.4 vs 186.5±19.9 and 171.1±21.5 ms, P <0.001). In contrast, RVOT pacing revealed a greater GLS (-14.69±4.92 vs -13.12±4.76 and -13.51±4.81%, P <0.001), shorter PSS time delay between the earliest and latest segments (236.0±87.9 vs 271.3±102.9 and 281.9±126.6%, P =0.007), and shorter SD of the time to the PSS (70.8±23.8 vs 82.7±30.8 and 81.5±33.7 ms, P =0.002) compared with RVA and RVMS pacing. These results suggest that the functional characteristics of RVOT pacing may be a more optimal pacing site than RVMS, regardless of the pacing QRS duration, in patients with atrioventricular conduction disorders.

  4. Rapid Extremity Pain Relief by Battlefield Acupuncture after Orthopedic Surgery: A Randomized Clinical Trial

    DTIC Science & Technology

    2017-03-21

    FINAL REPORT Project Title: Rapid Extremity Pain Relief by Battlefield Acupuncture after Orthopedic Surgery: A Randomized Clinical Trial...Center ATTN: DTIC-OA 8725 John J. Kingman Rd Fort Belvoir, VA 22060-6218 Submitted by: Jill M. Clark, MBA/HCM, CCRP, CCRC Senior Research ...Associate/ Research Manager Clinical Investigation Program Mike O’Callaghan Federal Medical Center (MOFMC) 4700 Las Vegas Blvd North, Bldg 1300, Room

  5. [Role of cyclic adenosine monophosphate response element binding protein in ventricular pacing induced cardiac electrical remodeling in a canine model].

    PubMed

    Chen, Xuesi; Chen, Xingxing; Cheng, Junhua; Hong, Jun; Zheng, Cheng; Zhao, Jinglin; Li, Jin; Lin, Jiafeng

    2015-04-01

    This project is designed to explore the potential role of cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) in cardiac electrical remodeling induced by pacing at different ventricular positions in dogs. An animal model by implanting the pacemakers in beagles was established. According to the different pacing positions, the animals were divided into 4 groups:conditional control group (n=6), left ventricle pacing group (n=6), right ventricle pacing group (n=6) and bi-ventricle pacing group (n=6). Cardiac and electrical remodeling were observed by echocardiography, electrocardiogram and plasma BNP. Myocardial pathology and protein expression of extracellular regulated protein kinases1/2 (ERK1/2), P38 mitogen activated protein kinases (P38 MAPK) and CREB were examined at 4 weeks post pacing. Cardiac structure and plasma BNP level were similar among 4 groups (all P>0.05). Electrocardiogram derived Tp-Te interval was significantly prolonged post pacing (92±11, 91±10, and 79±13 ms vs. 60±12 ms), and the Tp-Te interval in bi-ventricle pacing group was shorter than in left or right ventricle pacing group (P < 0.05). Western blot results showed that the expression of p-ERK1/2 in left ventricular myocardium of left ventricle pacing group, right ventricular myocardium of right ventricle pacing group and bi-ventricular myocardium of bi-ventricle pacing group was 2.7±0.4, 2.4±0.2, 1.7±0.1 and 1.9±0.2, respectively, the expression of p-P38 MAPK was 1.9±0.3, 1.7±0.2, 0.8±0.1 and 1.1±0.1, respectively, and the expression of p-CREB was 2.1±0.2, 2.0±0.2, 2.7±0.4 and 2.6±0.3, respectively. The p-ERK1/2 and p-P38 MAPK expression of bi-ventricle pacing group was lower,but the p-CREB expression was higher compared to the other pacing groups (P < 0.05). Ventricular pacing could induce electrical remodeling evidenced by prolonged Tp-Te interval and increased phosphorylation of ERK1/2 and p38 MAPK and reduced phosphorylation of CREB. Compared with single ventricle pacing, bi-ventricle pacing could attenuate electrical remodeling in this model.

  6. Altering Pace Control and Pace Regulation: Attentional Focus Effects during Running.

    PubMed

    Brick, Noel E; Campbell, Mark J; Metcalfe, Richard S; Mair, Jacqueline L; Macintyre, Tadhg E

    2016-05-01

    To date, there are no published studies directly comparing self-controlled (SC) and externally controlled (EC) pace endurance tasks. However, previous research suggests pace control may impact on cognitive strategy use and effort perceptions. The primary aim of this study was to investigate the effects of manipulating perception of pace control on attentional focus, physiological, and psychological outcomes during running. The secondary aim was to determine the reproducibility of self-paced running performance when regulated by effort perceptions. Twenty experienced endurance runners completed four 3-km time trials on a treadmill. Subjects completed two SC pace trials, one perceived exertion clamped (PE) trial, and one EC pace time trial. PE and EC were completed in a counterbalanced order. Pacing strategy for EC and perceived exertion instructions for PE replicated the subjects' fastest SC time trial. Subjects reported a greater focus on cognitive strategies such as relaxing and optimizing running action during EC than during SC. The mean HR was 2% lower during EC than that during SC despite an identical pacing strategy. Perceived exertion did not differ between the three conditions. However, increased internal sensory monitoring coincided with elevated effort perceptions in some subjects during EC and a 10% slower completion time for PE (13.0 ± 1.6 min) than that for SC (11.8 ± 1.2 min). Altering pace control and pace regulation impacted on attentional focus. External control over pacing may facilitate performance, particularly when runners engage attentional strategies conducive to improved running efficiency. However, regulating pace based on effort perceptions alone may result in excessive monitoring of bodily sensations and a slower running speed. Accordingly, attentional focus interventions may prove beneficial for some athletes to adopt task-appropriate attentional strategies to optimize performance.

  7. Accelerated graft dysfunction in heart transplant patients with persistent atrioventricular conduction block.

    PubMed

    Lee, William; Tay, Andre; Walker, Bruce D; Kuchar, Dennis L; Hayward, Christopher S; Spratt, Phillip; Subbiah, Rajesh N

    2016-12-01

    Bradyarrhythmia following heart transplantation is common-∼7.5-24% of patients require permanent pacemaker (PPM) implantation. While overall mortality is similar to their non-paced counterparts, the effects of chronic right ventricular pacing (CRVP) in heart transplant patients have not been studied. We aim to examine the effects of CRVP on heart failure and mortality in heart transplant patients. Records of heart transplant recipients requiring PPM at St Vincent's Hospital, Sydney, Australia between January 1990 and January 2015 were examined. Patient's without a right ventricular (RV) pacing lead or a follow-up time of <1 year were excluded. Patients with pre-existing abnormal left ventricular function (<50%) were analysed separately. Patients were grouped by pacing dependence (100% pacing dependent vs. non-pacing dependent). The primary endpoint was clinical or echocardiographic heart failure (<35%) in the first 5 years post-PPM. Thirty-three of 709 heart transplant recipients were studied. Two patients had complete RV pacing dependence, and the remaining 31 patients had varying degrees of pacing requirement, with an underlying ventricular escape rhythm. The primary endpoint occurred significantly more in the pacing-dependent group; 2 (100%) compared with 2 (6%) of the non pacing dependent group (P < 0.0001 by log-rank analysis, HR = 24.58). Non-pacing-dependent patients had reversible causes for heart failure, unrelated to pacing. In comparison, there was no other cause of heart failure in the pacing-dependent group. Permanent atrioventricular block is rare in the heart transplant population. We have demonstrated CRVP as a potential cause of accelerated graft failure in pacing-dependent heart transplant patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  8. Prospective randomized study to assess the efficacy of site and rate of atrial pacing on long-term progression of atrial fibrillation in sick sinus syndrome: Septal Pacing for Atrial Fibrillation Suppression Evaluation (SAFE) Study.

    PubMed

    Lau, Chu-Pak; Tachapong, Ngarmukos; Wang, Chun-Chieh; Wang, Jing-Feng; Abe, Haruhiko; Kong, Chi-Woon; Liew, Reginald; Shin, Dong-Gu; Padeletti, Luigi; Kim, You-Ho; Omar, Razali; Jirarojanakorn, Kreingkrai; Kim, Yoon-Nyun; Chen, Mien-Cheng; Sriratanasathavorn, Charn; Munawar, Muhammad; Kam, Ruth; Chen, Jan-Yow; Cho, Yong-Keun; Li, Yi-Gang; Wu, Shu-Lin; Bailleul, Christophe; Tse, Hung-Fat

    2013-08-13

    Atrial-based pacing is associated with lower risk of atrial fibrillation (AF) in sick sinus syndrome compared with ventricular pacing; nevertheless, the impact of site and rate of atrial pacing on progression of AF remains unclear. We evaluated whether long-term atrial pacing at the right atrial (RA) appendage versus the low RA septum with (ON) or without (OFF) a continuous atrial overdrive pacing algorithm can prevent the development of persistent AF. We randomized 385 patients with paroxysmal AF and sick sinus syndrome in whom a pacemaker was indicated to pacing at RA appendage ON (n=98), RA appendage OFF (n=99), RA septum ON (n=92), or RA septum OFF (n=96). The primary outcome was the occurrence of persistent AF (AF documented at least 7 days apart or need for cardioversion). Demographic data were homogeneous across both pacing site (RA appendage/RA septum) and atrial overdrive pacing (ON/OFF). After a mean follow-up of 3.1 years, persistent AF occurred in 99 patients (25.8%; annual rate of persistent AF, 8.3%). Alternative site pacing at the RA septum versus conventional RA appendage (hazard ratio=1.18; 95% confidence interval, 0.79-1.75; P=0.65) or continuous atrial overdrive pacing ON versus OFF (hazard ratio=1.17; 95% confidence interval, 0.79-1.74; P=0.69) did not prevent the development of persistent AF. In patients with paroxysmal AF and sick sinus syndrome requiring pacemaker implantation, an alternative atrial pacing site at the RA septum or continuous atrial overdrive pacing did not prevent the development of persistent AF. URL: http://www.clinicaltrials.gov. UNIQUE IDENTIFIER: NCT00419640.

  9. Projected trends in high-mortality heatwaves under different scenarios of climate, population, and adaptation in 82 US communities.

    PubMed

    Anderson, G Brooke; Oleson, Keith W; Jones, Bryan; Peng, Roger D

    2018-02-01

    Some rare heatwaves have extreme daily mortality impacts; moderate heatwaves have lower daily impacts but occur much more frequently at present and so account for large aggregated impacts. We applied health-based models to project trends in high-mortality heatwaves, including proportion of all heatwaves expected to be high-mortality, using the definition that a high-mortality heatwave increases mortality risk by ≥20 %. We projected these trends in 82 US communities in 2061-2080 under two scenarios of climate change (RCP4.5, RCP8.5), two scenarios of population change (SSP3, SSP5), and three scenarios of community adaptation to heat (none, lagged, on-pace) for large- and medium-ensemble versions of the National Center for Atmospheric Research's Community Earth System Model. More high-mortality heatwaves were expected compared to present under all scenarios except on-pace adaptation, and population exposure was expected to increase under all scenarios. At least seven more high-mortality heatwaves were expected in a twenty-year period in the 82 study communities under RCP8.5 than RCP4.5 when assuming no adaptation. However, high-mortality heatwaves were expected to remain <1 % of all heatwaves and heatwave exposure under all scenarios. Projections were most strongly influenced by the adaptation scenario- going from a scenario of on-pace to lagged adaptation or from lagged to no adaptation more than doubled the projected number of and exposure to high-mortality heatwaves. Based on our results, fewer high-mortality heatwaves are expected when following RCP4.5 versus RCP8.5 and under higher levels of adaptation, but high-mortality heatwaves are expected to remain a very small proportion of total heatwave exposure.

  10. Tactical Behaviors in Men's 800-m Olympic and World-Championship Medalists: A Changing of the Guard.

    PubMed

    Sandford, Gareth N; Pearson, Simon; Allen, Sian V; Malcata, Rita M; Kilding, Andrew E; Ross, Angus; Laursen, Paul B

    2018-02-01

    To assess the longitudinal evolution of tactical behaviors used to medal in men's 800-m Olympic Games (OG) or world-championship (WC) events in the recent competition era (2000-2016). Thirteen OG and WC events were characterized for 1st- and 2nd-lap splits using available footage from YouTube. Positive pacing strategies were defined as a faster 1st lap. Season's best 800-m time and world ranking, reflective of an athlete's "peak condition," were obtained to determine relationships between adopted tactics and physical condition prior to the championships. Seven championship events provided coverage of all medalists to enable determination of average 100-m speed and sector pacing of medalists. From 2011 onward, 800-m OG and WC medalists showed a faster 1st lap by 2.2 ± 1.1 s (mean, ±90% confidence limits; large difference, very likely), contrasting a possibly faster 2nd lap from 2000 to 2009 (0.5, ±0.4 s; moderate difference). A positive pacing strategy was related to a higher world ranking prior to the championships (r = .94, .84-.98; extremely large, most likely). After 2011, the fastest 100-m sector from 800-m OG and WC medalists was faster than before 2009 by 0.5, ±0.2 m/s (large difference, most likely). A secular change in tactical racing behavior appears evident in 800-m championships; since 2011, medalists have largely run faster 1st laps and have faster 100-m sector-speed requirements. This finding may be pertinent for training, tactical preparation, and talent identification of athletes preparing for 800-m running at OGs and WCs.

  11. 42 CFR 460.90 - PACE benefits under Medicare and Medicaid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false PACE benefits under Medicare and Medicaid. 460.90 Section 460.90 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... FOR THE ELDERLY (PACE) PACE Services § 460.90 PACE benefits under Medicare and Medicaid. If a Medicare...

  12. Real-time magnetic resonance imaging-guided transcatheter aortic valve replacement.

    PubMed

    Miller, Justin G; Li, Ming; Mazilu, Dumitru; Hunt, Tim; Horvath, Keith A

    2016-05-01

    To demonstrate the feasibility of Real-time magnetic resonance imaging (rtMRI) guided transcatheter aortic valve replacement (TAVR) with an active guidewire and an MRI compatible valve delivery catheter system in a swine model. The CoreValve system was minimally modified to be MRI-compatible by replacing the stainless steel components with fluoroplastic resin and high-density polyethylene components. Eight swine weighing 60-90 kg underwent rtMRI-guided TAVR with an active guidewire through a left subclavian approach. Two imaging planes (long-axis view and short-axis view) were used simultaneously for real-time imaging during implantation. Successful deployment was performed without rapid ventricular pacing or cardiopulmonary bypass. Postdeployment images were acquired to evaluate the final valve position in addition to valvular and cardiac function. Our results show that the CoreValve can be easily and effectively deployed through a left subclavian approach using rtMRI guidance, a minimally modified valve delivery catheter system, and an active guidewire. This method allows superior visualization before deployment, thereby allowing placement of the valve with pinpoint accuracy. rtMRI has the added benefit of the ability to perform immediate postprocedural functional assessment, while eliminating the morbidity associated with radiation exposure, rapid ventricular pacing, contrast media renal toxicity, and a more invasive procedure. Use of a commercially available device brings this rtMRI-guided approach closer to clinical reality. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  13. Drinking-water treatment, climate change, and childhood gastrointestinal illness projections for northern Wisconsin (USA) communities drinking untreated groundwater

    NASA Astrophysics Data System (ADS)

    Uejio, Christopher K.; Christenson, Megan; Moran, Colleen; Gorelick, Mark

    2017-06-01

    This study examined the relative importance of climate change and drinking-water treatment for gastrointestinal illness incidence in children (age <5 years) from period 2046-2065 compared to 1991-2010. The northern Wisconsin (USA) study focused on municipalities distributing untreated groundwater. A time-series analysis first quantified the observed (1991-2010) precipitation and gastrointestinal illness associations after controlling for seasonality and temporal trends. Precipitation likely transported pathogens into drinking-water sources or into leaking water-distribution networks. Building on observed relationships, the second analysis projected how climate change and drinking-water treatment installation may alter gastrointestinal illness incidence. Future precipitation values were modeled by 13 global climate models and three greenhouse-gas emissions levels. The second analysis was rerun using three pathways: (1) only climate change, (2) climate change and the same slow pace of treatment installation observed over 1991-2010, and (3) climate change and the rapid rate of installation observed over 2011-2016. The results illustrate the risks that climate change presents to small rural groundwater municipalities without drinking water treatment. Climate-change-related seasonal precipitation changes will marginally increase the gastrointestinal illness incidence rate (mean: ˜1.5%, range: -3.6-4.3%). A slow pace of treatment installation somewhat decreased precipitation-associated gastrointestinal illness incidence (mean: ˜3.0%, range: 0.2-7.8%) in spite of climate change. The rapid treatment installation rate largely decreases the gastrointestinal illness incidence (mean: ˜82.0%, range: 82.0-83.0%).

  14. Declines in low-elevation subalpine tree populations outpace growth in high-elevation populations with warming

    DOE PAGES

    Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.; ...

    2017-02-08

    Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively. Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers. Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forestmore » and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine. Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.« less

  15. Declines in low-elevation subalpine tree populations outpace growth in high-elevation populations with warming

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.

    Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively. Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers. Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forestmore » and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine. Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.« less

  16. Declines in low-elevation subalpine tree populations outpace growth in high-elevation populations with warming

    USGS Publications Warehouse

    Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.; Veblen, Thomas T; Smith, Jeremy M.; Kueppers, Lara M.

    2017-01-01

    Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively.Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers.Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forest and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine.Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.

  17. Sildenafil (Viagra) prolongs cardiac repolarization by blocking the rapid component of the delayed rectifier potassium current.

    PubMed

    Geelen, P; Drolet, B; Rail, J; Bérubé, J; Daleau, P; Rousseau, G; Cardinal, R; O'Hara, G E; Turgeon, J

    2000-07-18

    BACKGROUND-Several cases of unexpected death have been reported with sildenafil in patients predisposed to ischemic cardiac events. Although acute episodes of ischemia could account for some of these deaths, we hypothesized that sildenafil may have unsuspected electrophysiological effects predisposing some patients to proarrhythmia. METHODS AND RESULTS-Studies were undertaken in 10 isolated guinea pig hearts that demonstrated prolongation of cardiac repolarization in a reverse use-dependent manner by sildenafil 30 mcmol/L. Action potential duration increased 15% from baseline 117+/-3 to 134+/-2 ms with sildenafil during pacing at 250 ms cycle length, whereas a 6% increase from 99+/-2 to 105+/-2 ms was seen with pacing at 150 ms cycle length. Experiments in human ether-a-go-go-related gene (HERG)-transfected HEK293 cells (n=30) demonstrated concentration-dependent block of the rapid component (I(Kr)) of the delayed rectifier potassium current: activating current was 50% decreased at 100 mcmol/L. This effect was confirmed using HERG-transfected Chinese hamster ovary (CHO) cells, which exhibit no endogenous I(K)-like current. CONCLUSIONS-Sildenafil possesses direct cardiac electrophysiological effects similar to class III antiarrhythmic drugs. These effects are observed at concentrations that may be found in conditions of impaired drug elimination such as renal or hepatic insufficiency, during coadministration of another CYP3A substrate/inhibitor, or after drug overdose and offer a new potential explanation for sudden death during sildenafil treatment.

  18. Safety of the Wearable Cardioverter Defibrillator (WCD) in Patients with Implanted Pacemakers.

    PubMed

    Schmitt, Joern; Abaci, Guezine; Johnson, Victoria; Erkapic, Damir; Gemein, Christopher; Chasan, Ritvan; Weipert, Kay; Hamm, Christian W; Klein, Helmut U

    2017-03-01

    The wearable cardioverter defibrillator (WCD) is an important approach for better risk stratification, applied to patients considered to be at high risk of sudden arrhythmic death. Patients with implanted pacemakers may also become candidates for use of the WCD. However, there is a potential risk that pacemaker signals may mislead the WCD detection algorithm and cause inappropriate WCD shock delivery. The aim of the study was to test the impact of different types of pacing, various right ventricular (RV) lead positions, and pacing modes for potential misleading of the WCD detection algorithm. Sixty patients with implanted pacemakers received the WCD for a short time and each pacing mode (AAI, VVI, and DDD) was tested for at least 30 seconds in unipolar and bipolar pacing configuration. In case of triggering the WCD detection algorithm and starting the sequence of arrhythmia alarms, shock delivery was prevented by pushing of the response buttons. In six of 60 patients (10%), continuous unipolar pacing in DDD mode triggered the WCD detection algorithm. In no patient, triggering occurred with bipolar DDD pacing, unipolar and bipolar AAI, and VVI pacing. Triggering was independent of pacing amplitude, RV pacing lead position, and pulse generator implantation site. Unipolar DDD pacing bears a high risk of false triggering of the WCD detection algorithm. Other types of unipolar pacing and all bipolar pacing modes do not seem to mislead the WCD detection algorithm. Therefore, patients with no reprogrammable unipolar DDD pacing should not become candidates for the WCD. © 2016 Wiley Periodicals, Inc.

  19. Variables affecting the manifestation of and intensity of pacing behavior: A preliminary case study in zoo-housed polar bears.

    PubMed

    Cless, Isabelle T; Lukas, Kristen E

    2017-09-01

    High-speed video analysis was used to quantify two aspects of gait in 10 zoo-housed polar bears. These two variables were then examined as to how they differed in the conditions of pacing versus locomoting for each bear. Percent difference calculations measured the difference between pacing and locomoting data for each bear. We inferred that the higher the percent difference between pacing and locomoting in a given subject, the more intense the pacing may be. The percent difference values were analyzed alongside caregiver survey data defining the locations, frequency, and anticipatory nature of pacing in each bear, as well as each bear's age and sex, to determine whether any variables were correlated. The frequency and intensity of pacing behavior were not correlated. However, location of pacing was significantly correlated both with the subjects' age and whether or not the subject was classified as an anticipatory pacer. Bears appeared to select specific spots within their exhibits to pace, and the location therefore seemed tied to underlying motivation for the behavior. Additionally, bears that were classified in the survey as pacing anticipatorily displayed significantly more intense pacing behavior as quantified by gait analysis. © 2017 Wiley Periodicals, Inc.

  20. 42 CFR 460.122 - PACE organization's appeals process.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Rights § 460.122 PACE organization's appeals process. For purposes...

  1. 42 CFR 460.122 - PACE organization's appeals process.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Rights § 460.122 PACE organization's appeals process. For purposes...

  2. 42 CFR 460.170 - Reinstatement in PACE.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.170 Reinstatement in PACE. (a) A previously...

  3. 42 CFR 460.170 - Reinstatement in PACE.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.170 Reinstatement in PACE. (a) A previously...

  4. Effects of pacing magnitudes and forms on bistability width in a modeled ventricular tissue

    NASA Astrophysics Data System (ADS)

    Huang, Xiaodong; Liu, Xuemei; Zheng, Lixian; Mi, Yuanyuan; Qian, Yu

    2013-07-01

    Bistability in periodically paced cardiac tissue is relevant to cardiac arrhythmias and its control. In the present paper, one-dimensional tissue of the phase I Luo-Rudy model is numerically investigated. The effects of various parameters of pacing signals on bistability width are studied. The following conclusions are obtained: (i) Pacing can be classified into two types: pulsatile and sinusoidal types. Pulsatile pacing reduces bistability width as its magnitude is increased. Sinusoidal pacing increases the width as its amplitude is increased. (ii) In a pacing period the hyperpolarizing part plays a more important role than the depolarizing part. Variations of the hyperpolarizing ratio in a period evidently change the width of bistability and its variation tendency. (iii) A dynamical mechanism is proposed to qualitatively explain the phenomena, which reveals the reason for the different effects of pulsatile and sinusoidal pacing on bistability. The methods for changing bistability width by external pacing may help control arrhythmias in cardiology.

  5. Triggered intracellular calcium waves in dog and human left atrial myocytes from normal and failing hearts.

    PubMed

    Aistrup, Gary L; Arora, Rishi; Grubb, Søren; Yoo, Shin; Toren, Benjamin; Kumar, Manvinder; Kunamalla, Aaron; Marszalec, William; Motiwala, Tej; Tai, Shannon; Yamakawa, Sean; Yerrabolu, Satya; Alvarado, Francisco J; Valdivia, Hector H; Cordeiro, Jonathan M; Shiferaw, Yohannes; Wasserstrom, John Andrew

    2017-11-01

    Abnormal intracellular Ca2+ cycling contributes to triggered activity and arrhythmias in the heart. We investigated the properties and underlying mechanisms for systolic triggered Ca2+ waves in left atria from normal and failing dog hearts. Intracellular Ca2+ cycling was studied using confocal microscopy during rapid pacing of atrial myocytes (36 °C) isolated from normal and failing canine hearts (ventricular tachypacing model). In normal atrial myocytes (NAMs), Ca2+ waves developed during rapid pacing at rates ≥ 3.3 Hz and immediately disappeared upon cessation of pacing despite high sarcoplasmic reticulum (SR) load. In heart failure atrial myocytes (HFAMs), triggered Ca2+ waves (TCWs) developed at a higher incidence at slower rates. Because of their timing, TCW development relies upon action potential (AP)-evoked Ca2+ entry. The distribution of Ca2+ wave latencies indicated two populations of waves, with early events representing TCWs and late events representing conventional spontaneous Ca2+ waves. Latency analysis also demonstrated that TCWs arise after junctional Ca2+ release has occurred and spread to non-junctional (cell core) SR. TCWs also occurred in intact dog atrium and in myocytes from humans and pigs. β-adrenergic stimulation increased Ca2+ release and abolished TCWs in NAMs but was ineffective in HFAMs making this a potentially effective adaptive mechanism in normals but potentially arrhythmogenic in HF. Block of Ca-calmodulin kinase II also abolished TCWs, suggesting a role in TCW formation. Pharmacological manoeuvres that increased Ca2+ release suppressed TCWs as did interventions that decreased Ca2+ release but these also severely reduced excitation-contraction coupling. TCWs develop during the atrial AP and thus could affect AP duration, producing repolarization gradients and creating a substrate for reentry, particularly in HF where they develop at slower rates and a higher incidence. TCWs may represent a mechanism for the initiation of atrial fibrillation particularly in HF. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions please email: journals.permissions@oup.com.

  6. Predictors of temporary epicardial pacing wires use after valve surgery

    PubMed Central

    2014-01-01

    Background Although temporary cardiac pacing is infrequently needed, temporary epicardial pacing wires are routinely inserted after valve surgery. As they are associated with infrequent, but life threatening complications, and the decreased need for postoperative pacing in a group of low risk patients; this study aims to identify the predictors of temporary cardiac pacing after valve surgery. Methods A retrospective analysis of data collected prospectively on 400 consecutive valve surgery patients between May 2002 and December 2012 was performed. Patients were grouped according to avoidance or insertion of temporary pacing wires, and were further subdivided according to temporary cardiac pacing need. Multiple logistic regression was used to determine the predictors of temporary cardiac pacing. Results 170 (42.5%) patients did not have insertion of temporary pacing wires and none of them needed temporary pacing. 230 (57.5%) patients had insertion of temporary pacing wires and among these, only 55 (23.9%) required temporary pacing who were compared with the remaining 175 (76.1%) patients in the main analysis. The determinants of temporary cardiac pacing (adjusted odds ratios; 95% confidence interval) were as follows: increased age (1.1; 1.1, 1.3, p = 0.002), New York Heart Association class III- IV (5.6; 1.6, 20.2, p = 0.008) , pulmonary artery pressure ≥ 50 mmHg (22.0; 3.4, 142.7, p = 0.01), digoxin use (8.0; 1.3, 48.8, p = 0.024), multiple valve surgery (13.5; 1.5, 124.0, p = 0.021), aorta cross clamp time ≥ 60 minutes (7.8; 1.6, 37.2, p = 0.010), and valve annulus calcification (7.9; 2.0, 31.7, p = 0.003). Conclusion Although limited by sample size, the present results suggest that routine use of temporary epicardial pacing wires after valve surgery is only necessary for high risk patients. Preoperative identification and aggressive management of predictors of temporary cardiac pacing and the possible modulation of intraoperative techniques can decrease the need of temporary cardiac pacing. Prospective randomized controlled studies on a larger number of patients are necessary to draw solid conclusions regarding the selective use of temporary epicardial pacing wires in valve surgery. PMID:24521215

  7. 42 CFR 460.30 - Program agreement requirement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.30 Program agreement requirement. (a) A PACE organization must...

  8. 42 CFR 460.30 - Program agreement requirement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Program Agreement § 460.30 Program agreement requirement. (a) A PACE organization must...

  9. 42 CFR 460.50 - Termination of PACE program agreement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Sanctions, Enforcement Actions, and Termination § 460.50 Termination of PACE...

  10. 42 CFR 460.50 - Termination of PACE program agreement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Sanctions, Enforcement Actions, and Termination § 460.50 Termination of PACE...

  11. 42 CFR 460.180 - Medicare payment to PACE organizations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Payment § 460.180 Medicare payment to PACE organizations. (a) Principle of...

  12. The Influence of Solar Power Plants on Microclimatic Conditions and the Biotic Community in Chilean Desert Environments.

    PubMed

    Suuronen, Anna; Muñoz-Escobar, Christian; Lensu, Anssi; Kuitunen, Markku; Guajardo Celis, Natalia; Espinoza Astudillo, Pablo; Ferrú, Marcos; Taucare-Ríos, Andrés; Miranda, Marcelo; Kukkonen, Jussi V K

    2017-10-01

    The renewable energy sector is growing at a rapid pace in northern Chile and the solar energy potential is one of the best worldwide. Therefore, many types of solar power plant facilities are being built to take advantage of this renewable energy resource. Solar energy is considered a clean source of energy, but there are potential environmental effects of solar technology, such as landscape fragmentation, extinction of local biota, microclimate changes, among others. To be able to minimize environmental impacts of solar power plants, it is important to know what kind of environmental conditions solar power plants create. This study provides information about abiotic and biotic conditions in the vicinity of photovoltaic solar power plants. Herein, the influence of these power plants as drivers of new microclimate conditions and arthropods diversity composition in the Atacama Desert was evaluated. Microclimatic conditions between panel mounts was found to be more extreme than in the surrounding desert yet beneath the panels temperature is lower and relative humidity higher than outside the panel area. Arthropod species composition was altered in fixed-mount panel installations. In contrast, solar tracking technology showed less influence on microclimate and species composition between Sun and Shade in the power plant. Shady conditions provided a refuge for arthropod species in both installation types. For example, Dipterans were more abundant in the shade whereas Solifugaes were seldom present in the shade. The presented findings have relevance for the sustainable planning and construction of solar power plants.

  13. The Influence of Solar Power Plants on Microclimatic Conditions and the Biotic Community in Chilean Desert Environments

    NASA Astrophysics Data System (ADS)

    Suuronen, Anna; Muñoz-Escobar, Christian; Lensu, Anssi; Kuitunen, Markku; Guajardo Celis, Natalia; Espinoza Astudillo, Pablo; Ferrú, Marcos; Taucare-Ríos, Andrés; Miranda, Marcelo; Kukkonen, Jussi V. K.

    2017-10-01

    The renewable energy sector is growing at a rapid pace in northern Chile and the solar energy potential is one of the best worldwide. Therefore, many types of solar power plant facilities are being built to take advantage of this renewable energy resource. Solar energy is considered a clean source of energy, but there are potential environmental effects of solar technology, such as landscape fragmentation, extinction of local biota, microclimate changes, among others. To be able to minimize environmental impacts of solar power plants, it is important to know what kind of environmental conditions solar power plants create. This study provides information about abiotic and biotic conditions in the vicinity of photovoltaic solar power plants. Herein, the influence of these power plants as drivers of new microclimate conditions and arthropods diversity composition in the Atacama Desert was evaluated. Microclimatic conditions between panel mounts was found to be more extreme than in the surrounding desert yet beneath the panels temperature is lower and relative humidity higher than outside the panel area. Arthropod species composition was altered in fixed-mount panel installations. In contrast, solar tracking technology showed less influence on microclimate and species composition between Sun and Shade in the power plant. Shady conditions provided a refuge for arthropod species in both installation types. For example, Dipterans were more abundant in the shade whereas Solifugaes were seldom present in the shade. The presented findings have relevance for the sustainable planning and construction of solar power plants.

  14. DefenseLink Special: Travels with Pace, March 2006

    Science.gov Websites

    Us Travels with Pace Chairman of the Joint Chiefs of Staff Marine Gen. Peter Pace U.S. Marine Gen . Peter Pace, chairman of the Joint Chiefs of Staff, speaks to students attending the Turkish War College U.S. Air Force Staff Sgt. D. Myles Cullen Hi-Res Pace Wraps Up Visit to Allied Nations WASHINGTON

  15. Anatomical approach to permanent His bundle pacing: Optimizing His bundle capture.

    PubMed

    Vijayaraman, Pugazhendhi; Dandamudi, Gopi

    2016-01-01

    Permanent His bundle pacing is a physiological alternative to right ventricular pacing. In this article we describe our approach to His bundle pacing in patients with AV nodal and intra-Hisian conduction disease. It is essential for the implanters to understand the anatomic variations of the His bundle course and its effect on the type of His bundle pacing achieved. We describe several case examples to illustrate our anatomical approach to permanent His bundle pacing in this article. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Black Sea outflow response to Holocene meltwater events.

    PubMed

    Herrle, Jens O; Bollmann, Jörg; Gebühr, Christina; Schulz, Hartmut; Sheward, Rosie M; Giesenberg, Annika

    2018-03-06

    During the Holocene, North American ice sheet collapse and rapid sea-level rise reconnected the Black Sea with the global ocean. Rapid meltwater releases into the North Atlantic and associated climate change arguably slowed the pace of Neolithisation across southeastern Europe, originally hypothesized as a catastrophic flooding that fueled culturally-widespread deluge myths. However, we currently lack an independent record linking the timing of meltwater events, sea-level rise and environmental change with the timing of Neolithisation in southeastern Europe. Here, we present a sea surface salinity record from the Northern Aegean Sea indicative of two meltwater events at ~8.4 and ~7.6 kiloyears that can be directly linked to rapid declines in the establishment of Neolithic sites in southeast Europe. The meltwater events point to an increased outflow of low salinity water from the Black Sea driven by rapid sea level rise >1.4 m following freshwater outbursts from Lake Agassiz and the final decay of the Laurentide ice sheet. Our results shed new light on the link between catastrophic sea-level rise and the Neolithisation of southeastern Europe, and present a historical example of how coastal populations could have been impacted by future rapid sea-level rise.

  17. Higher sympathetic nerve activity during ventricular (VVI) than during dual-chamber (DDD) pacing

    NASA Technical Reports Server (NTRS)

    Taylor, J. A.; Morillo, C. A.; Eckberg, D. L.; Ellenbogen, K. A.

    1996-01-01

    OBJECTIVES: We determined the short-term effects of single-chamber ventricular pacing and dual-chamber atrioventricular (AV) pacing on directly measured sympathetic nerve activity. BACKGROUND: Dual-chamber AV cardiac pacing results in greater cardiac output and lower systemic vascular resistance than does single-chamber ventricular pacing. However, it is unclear whether these hemodynamic advantages result in less sympathetic nervous system outflow. METHODS: In 13 patients with a dual-chamber pacemaker, we recorded the electrocardiogram, noninvasive arterial pressure (Finapres), respiration and muscle sympathetic nerve activity (microneurography) during 3 min of underlying basal heart rate and 3 min of ventricular and AV pacing at rates of 60 and 100 beats/min. RESULTS: Arterial pressure was lowest and muscle sympathetic nerve activity was highest at the underlying basal heart rate. Arterial pressure increased with cardiac pacing and was greater with AV than with ventricular pacing (change in mean blood pressure +/- SE: 10 +/- 3 vs. 2 +/- 2 mm Hg at 60 beats/min; 21 +/- 5 vs. 14 +/- 2 mm Hg at 100 beats/min; p < 0.05). Sympathetic nerve activity decreased with cardiac pacing and the decline was greater with AV than with ventricular pacing (60 beats/min -40 +/- 11% vs. -17 +/- 7%; 100 beats/min -60 +/- 9% vs. -48 +/- 10%; p < 0.05). Although most patients showed a strong inverse relation between arterial pressure and muscle sympathetic nerve activity, three patients with severe left ventricular dysfunction (ejection fraction < or = 30%) showed no relation between arterial pressure and sympathetic activity. CONCLUSIONS: Short-term AV pacing results in lower sympathetic nerve activity and higher arterial pressure than does ventricular pacing, indicating that cardiac pacing mode may influence sympathetic outflow simply through arterial baroreflex mechanisms. We speculate that the greater incidence of adverse outcomes in patients treated with single-chamber ventricular rather than dual-chamber pacing may be due in part to increased sympathetic nervous outflow.

  18. Right Ventricular Outflow Tract Septal Pacing Is Superior to Right Ventricular Apical Pacing

    PubMed Central

    Zou, Cao; Song, Jianping; Li, Hui; Huang, Xingmei; Liu, Yuping; Zhao, Caiming; Shi, Xin; Yang, Xiangjun

    2015-01-01

    Background The effects of right ventricular apical pacing (RVAP) and right ventricular outflow tract (RVOT) septal pacing on atrial and ventricular electrophysiology have not been thoroughly compared. Methods and Results To identify a more favorable pacing strategy with fewer adverse effects, 80 patients who had complete atrioventricular block with normal cardiac function and who were treated with either RVAP (n=42) or RVOT septal pacing (n=38) were recruited after an average of 2 years of follow‐up. The data from electrocardiography and echocardiography performed before pacemaker implantation and at the end of follow‐up were collected. The patients in the RVOT septal pacing and RVAP groups showed similar demographic and clinical characteristics before pacing treatments. After a mean follow‐up of 2 years, the final maximum P‐wave duration; P‐wave dispersion; Q‐, R‐, and S‐wave complex duration; left atrial volume index; left ventricular end‐systolic diameter; ratio of transmitral early diastolic filling velocity to mitral annular early diastolic velocity; and interventricular mechanical delay in the RVOT septal pacing group were significantly less than those in the RVAP group (P<0.05). The final left ventricular ejection fraction of the RVOT septal pacing group was significantly higher than that of the RVAP group (P<0.05). Conclusions Compared with RVAP, RVOT septal pacing has fewer adverse effects regarding atrial electrical activity and structure in patients with normal cardiac function. PMID:25896891

  19. 42 CFR 460.24 - Limit on number of PACE program agreements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.24 Limit on number of...

  20. 42 CFR 460.24 - Limit on number of PACE program agreements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.24 Limit on number of...

  1. Role of Molecular Biology in Diagnosis and Characterization of Vulvo-Vaginitis in Clinical Practice.

    PubMed

    Donders, Gilbert G G; Ravel, Jacques; Vitali, Beatrice; Netea, Mihai G; Salumets, Andres; Unemo, Magnus

    2017-01-01

    The diagnosis of vulvo-vaginal complaints has always been enigmatic in obstetrics and gynecology. Patients with clear, pathognomonic symptoms end up with a proper diagnosis and treatment most of the time, but unfortunately we are now living in a world where women reach out to the Internet and readily get all information as to which disease their symptoms correspond to and also find the appropriate treatment "over-the-counter." Because of this trend, we as specialists are increasingly confronted with patients with complex and combined conditions. At the same time, extremely sensitive and accurate diagnostic tools are now being developed at a rapid pace, allowing the physicians to diagnose vulvo-vaginal disease with a substantially increased precision. Moreover, many of these molecular biology (MB)-based tests have become so common and affordable that self-sampling and self-testing are no longer utopia. On the other hand, too much information that is too readily available and that is too affordable also encompasses pitfalls, leading to gross overtreatment and psychological burden. As experienced caregivers, we should supervise these evolutions, define their place and proper use as diagnostic tools, utilize their potential as ad hoc tools to follow-up treatment efficacy and guide how such tools can be used for responsible self-testing. In the present paper, responding to the need for appropriate, quality assured and accessible tests for vulvo-vaginitis and the huge potential delivered by the rapidly developing MB methods, we recommend the need for a broad and regular discussion forum, composed of both clinical and technical experts and opinion makers, in order to match the needs with the huge opportunities and ideally combine the initiatives and forces into the same direction. This forum should then translate conceived strategies into regularly updated, evidence-based national and international guidelines. © 2017 S. Karger AG, Basel.

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Radman, Ali M

    The Division of Natural Sciences and Mathematics is housed in the Wilson-Booker Science Building (WBSB) which previously consisted of six classrooms, a lecture room, three biology laboratories, one physics laboratory, one chemistry laboratory, one research laboratory, and three computer laboratories. However, due to rapid expansion in STEM majors, there was a dire need for more classroom and laboratory space to accommodate this expansion. Further, since the College started integrating research into the curriculum in 2004 in order to keep pace with the national trend in science education, it has become apparent that one small research laboratory that accommodates 10 studentsmore » will not keep pace with the growing needs of the new students interested in research. Therefore , it became imperative to add another research laboratory to augment the existing one. Thus, the new instrumentation/Research Laboratory will provide space for the new equipment and research space for an additional 8 - 10 students. In addition, the new WBSB wing also houses a Biochemisty/Molecular Biology Laboratory, an Organic Chemistry laboratory, an Animal Laboratory, a Seminar Room, two spacious classrooms, and 3 Faculty Offices. The impact of the new facility will be far-reaching.« less

  3. Effect of Right Ventricular versus Biventricular Pacing on Electrical Remodeling in the Normal Heart

    PubMed Central

    Saba, Samir; Mehdi, Haider; Mathier, Michael A.; Islam, M. Zahadul; Salama, Guy; London, Barry

    2010-01-01

    Background Biventricular (BIV) pacing can improve cardiac function in heart failure by altering the mechanical and electrical substrates. We investigated the effect of BIV versus right ventricular (RV) pacing on the normal heart. Methods and Results Male New Zealand White rabbits (n=33) were divided into 3 groups: sham-operated (control), RV pacing, and BIV pacing groups. Four weeks after surgery, the native QT (p=0.004) interval was significantly shorter in the BIV group compared to the RV or sham-operated groups. Also, compared to rabbits in the RV group, rabbits in the BIV group had shorter RV ventricular effective refractory period (VERP) at all cycle lengths, and shorter LV paced QT interval during the drive train of stimuli and close to refractoriness (p<0.001 for all comparisons). Protein expression of the KVLQT1 was significantly increased in the BIV group compared to the RV and control groups, while protein expression of SCN5A and connexin43 was significantly decreased in the RV compared to the other study groups. Erg protein expression was significantly increased in both pacing groups compared to the controls. Conclusions In this rabbit model, we demonstrate a direct effect of BIV but not RV pacing on shortening the native QT interval as well as the paced QT interval during burst pacing and close to the VERP. These findings underscore the fact that the effect of BIV pacing is partially mediated through direct electrical remodeling and may have implications as to the effect of BIV pacing on arrhythmia incidence and burden. PMID:20042767

  4. Interatrial septum versus right atrial appendage pacing for prevention of atrial fibrillation : A meta-analysis of randomized controlled trials.

    PubMed

    Zhang, L; Jiang, H; Wang, W; Bai, J; Liang, Y; Su, Y; Ge, J

    2017-07-28

    Interatrial septum (IAS) pacing seems to be a promising strategy for the prevention of atrial fibrillation (AF); however, studies have yielded conflicting results. This meta-analysis was to compare IAS with right atrial appendage (RAA) pacing on the prevention of postpacing AF occurrence. Pubmed, MEDLINE, EMBASE and Web of Science databases were searched through October 2016 for randomized controlled trials comparing IAS with RAA pacing on the prevention of AF. Data concerning study design, patient characteristics and outcomes were extracted. Risk ratio (RR), weighted mean differences (WMD) or standardized mean differences (SMD) were calculated using fixed or random effects models. A total of 12 trials involving 1146 patients with dual-chamber pacing were included. Although IAS was superior to RAA pacing in terms of reducing the number of AF episodes (SMD = -0.29, P = 0.05), AF burden (SMD = -0.41, P = 0.008) and P -wave duration (WMD = -34.45 ms, P < 0.0001), neither permanent AF occurrence (RR = 0.94, P = 0.58) nor recurrences of AF (RR = 0.88, P = 0.36) were reduced by IAS pacing. Nevertheless, no differences were observed concerning all-cause death (RR = 1.04, P = 0.88), procedure-related events (RR = 1.17, P = 0.69) and pacing parameters between IAS and RAA pacing in the follow-up period. IAS pacing is safe and as well tolerated as RAA pacing. Although IAS pacing may fail to prevent permanent AF occurrence and recurrences of AF, it is able to not only improve interatrial conduction, but also reduce AF burden.

  5. Effects of septal pacing on P wave characteristics: the value of three-dimensional echocardiography.

    PubMed

    Szili-Torok, Tamas; Bruining, Nico; Scholten, Marcoen; Kimman, Geert-Jan; Roelandt, Jos; Jordaens, Luc

    2003-01-01

    Interatrial septum (IAS) pacing has been proposed for the prevention of paroxysmal atrial fibrillation. IAS pacing is usually guided by fluoroscopy and P wave analysis. The authors have developed a new approach for IAS pacing using intracardiac echocardiography (ICE), and examined its effects on P wave characteristics. Cross-sectional images are acquired during pullback of the ICE transducer from the superior vena cava into the inferior vena cava by an electrocardiogram- and respiration-gated technique. The right atrium and IAS are then three-dimensionally reconstructed, and the desired pacing site is selected. After lead placement and electrical testing, another three-dimensional reconstruction is performed to verify the final lead position. The study included 14 patients. IAS pacing was achieved at seven suprafossal (SF) and seven infrafossal (IF) lead locations, all confirmed by three-dimensional imaging. IAS pacing resulted in a significant reduction of P wave duration as compared to sinus rhythm (99.7 +/- 18.7 vs 140.4 +/- 8.8 ms; P < 0.01). SF pacing was associated with a greater reduction of P wave duration than IF pacing (56.1 +/- 9.9 vs 30.2 +/- 13.6 ms; P < 0.01). P wave dispersion remained unchanged during septal pacing as compared to sinus rhythm (21.4 +/- 16.1 vs 13.5 +/- 13.9 ms; NS). Three-dimensional intracardiac echocardiography can be used to guide IAS pacing. SF pacing was associated with a greater decrease in P wave duration, suggesting that it is a preferable location to decrease interatrial conduction delay.

  6. Pacing a data transfer operation between compute nodes on a parallel computer

    DOEpatents

    Blocksome, Michael A [Rochester, MN

    2011-09-13

    Methods, systems, and products are disclosed for pacing a data transfer between compute nodes on a parallel computer that include: transferring, by an origin compute node, a chunk of an application message to a target compute node; sending, by the origin compute node, a pacing request to a target direct memory access (`DMA`) engine on the target compute node using a remote get DMA operation; determining, by the origin compute node, whether a pacing response to the pacing request has been received from the target DMA engine; and transferring, by the origin compute node, a next chunk of the application message if the pacing response to the pacing request has been received from the target DMA engine.

  7. Test techniques for evaluating flight displays

    NASA Technical Reports Server (NTRS)

    Haworth, Loran A.; Newman, Richard L.

    1993-01-01

    The rapid development of graphics technology allows for greater flexibility in aircraft displays, but display evaluation techniques have not kept pace. Historically, display evaluation has been based on subjective opinion and not on the actual aircraft/pilot performance. Existing electronic display specifications and evaluation techniques are reviewed. A display rating technique analogous to handling qualities ratings was developed and is recommended for future evaluations. The choice of evaluation pilots is also discussed and the use of a limited number of trained evaluators is recommended over the use of a large number of operational pilots.

  8. Operating safely in surgery and critical care with perioperative automation.

    PubMed

    Grover, Christopher; Barney, Kate

    2004-01-01

    A study by the Institute of Medicine (IOM) found that as many as 98,000 Americans die each year from preventable medical errors. These findings, combined with a growing spate of negative publicity, have brought patient safety to its rightful place at the healthcare forefront. Nowhere are patient safety issues more critical than in the anesthesia, surgery and critical care environments. These high-acuity settings--with their fast pace, complex and rapidly changing care regimens and mountains of diverse clinical data-arguably pose the greatest patient safety risk in the hospital.

  9. Enabling Technologies for the Future of Chemical Synthesis.

    PubMed

    Fitzpatrick, Daniel E; Battilocchio, Claudio; Ley, Steven V

    2016-03-23

    Technology is evolving at breakneck pace, changing the way we communicate, travel, find out information, and live our lives. Yet chemistry as a science has been slower to adapt to this rapidly shifting world. In this Outlook we use highlights from recent literature reports to describe how progresses in enabling technologies are altering this trend, permitting chemists to incorporate new advances into their work at all levels of the chemistry development cycle. We discuss the benefits and challenges that have arisen, impacts on academic-industry relationships, and future trends in the area of chemical synthesis.

  10. Rural-urban migration and urban employment opportunities in Nigeria.

    PubMed

    Okpara, E E

    1986-01-01

    The author suggests that most studies of rural-urban migration in the third world today are based on the European experience during the Industrial Revolution. He contends that the assumption that most migrants find wage employment in a rapidly growing modern industrial sector is not valid, particularly in Western Africa, where the pace of industrialization lags behind the rate of urbanization. Data from Nigeria are used to show that many potential migrants are aware of this situation and migrate seeking self-employment in informal sector trading activities.

  11. New technologies and worker safety in western agriculture.

    PubMed

    Fenske, Richard A

    2009-01-01

    The New Paths: Health and Safety in Western Agriculture conference, November 11-13, 2008, highlighted the role of technological innovation in agricultural production. The tree fruit industry in the Pacific Northwest has adopted a "technology road map" to reduce production costs and improve efficiency. An agricultural tour provided field demonstrations and discussions on such topics as mobile work platforms in orchards, traumatic and musculoskeletal injuries, and new pest control technologies. Occupational safety and health research will need to adapt to and keep pace with rapid changes in agricultural production processes.

  12. Pacing in Olympic track races: competitive tactics versus best performance strategy.

    PubMed

    Thiel, Christian; Foster, Carl; Banzer, Winfried; De Koning, Jos

    2012-01-01

    The purpose of this study was to describe pacing strategies in the 800 to 10,000-m Olympic finals. We asked 1) if Olympic finals differed from World Records, 2) how variable the pace was, 3) whether runners faced catastrophic events, and 4) for the winning strategy. Publically available data from the Beijing 2008 Olympic Games gathered by four transponder antennae under the 400-m track were analysed to extract descriptors of pacing strategies. Individual pacing patterns of 133 finalists were visualised using speed by distance plots. Six of eight plots differed from the patterns reported for World Records. The coefficient of running speed variation was 3.6-11.4%. In the long distance finals, runners varied their pace every 100 m by a mean 1.6-2.7%. Runners who were 'dropped' from the field achieved a stable running speed and displayed an endspurt. Top contenders used variable pacing strategies to separate themselves from the field. All races were decided during the final lap. Olympic track finalists employ pacing strategies which are different from World Record patterns. The observed micro- and macro-variations of pace may have implications for training programmes. Dropping off the pace of the leading group is an active step, and the result of interactive psychophysiological decision making.

  13. Meta-Analysis of Single-Case Research Design Studies on Instructional Pacing.

    PubMed

    Tincani, Matt; De Mers, Marilyn

    2016-11-01

    More than four decades of research on instructional pacing has yielded varying and, in some cases, conflicting findings. The purpose of this meta-analysis was to synthesize single-case research design (SCRD) studies on instructional pacing to determine the relative benefits of brisker or slower pacing. Participants were children and youth with and without disabilities in educational settings, excluding higher education. Tau-U, a non-parametric statistic for analyzing data in SCRD studies, was used to determine effect size estimates. The article extraction yielded 13 instructional pacing studies meeting contemporary standards for high quality SCRD research. Eleven of the 13 studies reported small to large magnitude effects when two or more pacing parameters were compared, suggesting that instructional pacing is a robust instructional variable. Brisker instructional pacing with brief inter-trial interval (ITI) produced small increases in correct responding and medium to large reductions in challenging behavior compared with extended ITI. Slower instructional pacing with extended wait-time produced small increases in correct responding, but also produced small increases in challenging behavior compared with brief wait-time. Neither brief ITI nor extended wait-time meets recently established thresholds for evidence-based practice, highlighting the need for further instructional pacing research. © The Author(s) 2016.

  14. Rapid emergence of climate change in environmental drivers of marine ecosystems.

    PubMed

    Henson, Stephanie A; Beaulieu, Claudie; Ilyina, Tatiana; John, Jasmin G; Long, Matthew; Séférian, Roland; Tjiputra, Jerry; Sarmiento, Jorge L

    2017-03-07

    Climate change is expected to modify ecological responses in the ocean, with the potential for important effects on the ecosystem services provided to humankind. Here we address the question of how rapidly multiple drivers of marine ecosystem change develop in the future ocean. By analysing an ensemble of models we find that, within the next 15 years, the climate change-driven trends in multiple ecosystem drivers emerge from the background of natural variability in 55% of the ocean and propagate rapidly to encompass 86% of the ocean by 2050 under a 'business-as-usual' scenario. However, we also demonstrate that the exposure of marine ecosystems to climate change-induced stress can be drastically reduced via climate mitigation measures; with mitigation, the proportion of ocean susceptible to multiple drivers within the next 15 years is reduced to 34%. Mitigation slows the pace at which multiple drivers emerge, allowing an additional 20 years for adaptation in marine ecological and socio-economic systems alike.

  15. Rapid emergence of climate change in environmental drivers of marine ecosystems

    PubMed Central

    Henson, Stephanie A.; Beaulieu, Claudie; Ilyina, Tatiana; John, Jasmin G.; Long, Matthew; Séférian, Roland; Tjiputra, Jerry; Sarmiento, Jorge L.

    2017-01-01

    Climate change is expected to modify ecological responses in the ocean, with the potential for important effects on the ecosystem services provided to humankind. Here we address the question of how rapidly multiple drivers of marine ecosystem change develop in the future ocean. By analysing an ensemble of models we find that, within the next 15 years, the climate change-driven trends in multiple ecosystem drivers emerge from the background of natural variability in 55% of the ocean and propagate rapidly to encompass 86% of the ocean by 2050 under a ‘business-as-usual' scenario. However, we also demonstrate that the exposure of marine ecosystems to climate change-induced stress can be drastically reduced via climate mitigation measures; with mitigation, the proportion of ocean susceptible to multiple drivers within the next 15 years is reduced to 34%. Mitigation slows the pace at which multiple drivers emerge, allowing an additional 20 years for adaptation in marine ecological and socio-economic systems alike. PMID:28267144

  16. Rapid emergence of climate change in environmental drivers of marine ecosystems

    NASA Astrophysics Data System (ADS)

    Henson, Stephanie A.; Beaulieu, Claudie; Ilyina, Tatiana; John, Jasmin G.; Long, Matthew; Séférian, Roland; Tjiputra, Jerry; Sarmiento, Jorge L.

    2017-03-01

    Climate change is expected to modify ecological responses in the ocean, with the potential for important effects on the ecosystem services provided to humankind. Here we address the question of how rapidly multiple drivers of marine ecosystem change develop in the future ocean. By analysing an ensemble of models we find that, within the next 15 years, the climate change-driven trends in multiple ecosystem drivers emerge from the background of natural variability in 55% of the ocean and propagate rapidly to encompass 86% of the ocean by 2050 under a `business-as-usual' scenario. However, we also demonstrate that the exposure of marine ecosystems to climate change-induced stress can be drastically reduced via climate mitigation measures; with mitigation, the proportion of ocean susceptible to multiple drivers within the next 15 years is reduced to 34%. Mitigation slows the pace at which multiple drivers emerge, allowing an additional 20 years for adaptation in marine ecological and socio-economic systems alike.

  17. Hot topics in biodiversity and climate change research

    PubMed Central

    Brook, Barry W.; Fordham, Damien A.

    2015-01-01

    With scientific and societal interest in biodiversity impacts of climate change growing enormously over the last decade, we analysed directions and biases in the recent most highly cited data papers in this field of research (from 2012 to 2014). The majority of this work relied on leveraging large databases of already collected historical information (but not paleo- or genetic data), and coupled these to new methodologies for making forward projections of shifts in species’ geographical ranges, with a focus on temperate and montane plants. A consistent finding was that the pace of climate-driven habitat change, along with increased frequency of extreme events, is outpacing the capacity of species or ecological communities to respond and adapt. PMID:26594350

  18. Diaphragmatic Myopotential Oversensing Caused by Change in Implantable Cardioverter Defibrillator Sensing Bandpass Filter.

    PubMed

    Ploux, Sylvain; Swerdlow, Charles D; Eschalier, Romain; Monteil, Benjamin; Ouali, Sana; Haïssaguerre, Michel; Bordachar, Pierre

    2016-07-01

    Diaphragmatic myopotential oversensing (DMO) causes inhibition of pacing and inappropriate detection of ventricular fibrillation in implantable cardioverter defibrillators (ICDs). It occurs almost exclusively with integrated bipolar leads and is extremely rare with dedicated bipolar leads. If DMO cannot be corrected by reducing programmed sensitivity, ventricular lead revision is often required. The new Low Frequency Attenuation (LFA) filter in St. Jude Medical ICDs (St. Jude Medical, Sylmar, CA, USA) alters the sensing bandpass to reduce T-wave oversensing. This paper aims to present the LFA filter as a reversible cause of DMO. Unnecessary lead revision can be avoided by the simple programming solution of deactivating this LFA filter. ©2016 Wiley Periodicals, Inc.

  19. Relationship between left atrium catheter contact force and pacing threshold.

    PubMed

    Barrio-López, Teresa; Ortiz, Mercedes; Castellanos, Eduardo; Lázaro, Carla; Salas, Jefferson; Madero, Sergio; Almendral, Jesús

    2017-08-01

    The purpose of this study is to analyze the relationship between contact force (CF) and pacing threshold in left atrium (LA). Six to ten LA sites were studied in 28 consecutive patients with atrial fibrillation undergoing pulmonary vein isolation. Median CF, bipolar and unipolar electrogram voltage, impedance, and bipolar and unipolar thresholds for consistent constant capture and for consistent intermittent capture were measured at each site. Pacing threshold measurements were performed at 188 LA sites. Both unipolar and bipolar pacing thresholds correlated significantly with median CF; however, unipolar pacing threshold correlated better (unipolar: Pearson R -0.45; p < 0.001; Spearman Rho -0.62; p < 0.001, bipolar: Pearson R -0.39; p < 0.001; Spearman Rho -0.52; p < 0.001). Consistent constant capture threshold had better correlation with median CF than consistent intermittent capture threshold for both unipolar and bipolar pacing (Pearson R -0.45; p < 0.001 and Spearman Rho -0.62; p < 0.001 vs. Pearson R -0.35; p < 0.001; Spearman Rho -0.52; p < 0.001). The best pacing threshold cutoff point to detect a good CF (>10 g) was 3.25 mA for unipolar pacing with 69% specificity and 73% sensitivity. Both increased to 80% specificity and 74% sensitivity for sites with normal bipolar voltage and a pacing threshold cutoff value of 2.85 mA. Pacing thresholds correlate with CF in human not previously ablated LA. Since the combination of a normal bipolar voltage and a unipolar pacing threshold <2.85 mA provide reasonable parameters of validity, pacing threshold could be of interest as a surrogate for CF in LA.

  20. Triple-site pacing for cardiac resynchronization in permanent atrial fibrillation - Acute phase results from a prospective observational study.

    PubMed

    Marques, Pedro; Nobre Menezes, Miguel; Lima da Silva, Gustavo; Bernardes, Ana; Magalhães, Andreia; Cortez-Dias, Nuno; Carpinteiro, Luís; de Sousa, João; Pinto, Fausto J

    2016-06-01

    Multi-site pacing is emerging as a new method for improving response to cardiac resynchronization therapy (CRT), but has been little studied, especially in patients with atrial fibrillation. We aimed to assess the effects of triple-site (Tri-V) vs. biventricular (Bi-V) pacing on hemodynamics and QRS duration. This was a prospective observational study of patients with permanent atrial fibrillation and ejection fraction <40% undergoing CRT implantation (n=40). One right ventricular (RV) lead was implanted in the apex and another in the right ventricular outflow tract (RVOT) septal wall. A left ventricular (LV) lead was implanted in a conventional venous epicardial position. Cardiac output (using the FloTrac™ Vigileo™ system), mean QRS and ejection fraction were calculated. Mean cardiac output was 4.81±0.97 l/min with Tri-V, 4.68±0.94 l/min with RVOT septal and LV pacing, and 4.68±0.94 l/min with RV apical and LV pacing (p<0.001 for Tri-V vs. both BiV). Mean pre-implantation QRS was 170±25 ms, 123±18 ms with Tri-V, 141±25 ms with RVOT septal pacing and LV pacing and 145±19 with RV apical and LV pacing (p<0.001 for Tri-V vs. both BiV and pre-implantation). Mean ejection fraction was significantly higher with Tri-V (30±11%) vs. Bi-V pacing (28±12% with RVOT septal and LV pacing and 28±11 with RV apical and LV pacing) and pre-implantation (25±8%). Tri-V pacing produced higher cardiac output and shorter QRS duration than Bi-V pacing. This may have a significant impact on the future of CRT. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  1. Risk perception influences athletic pacing strategy.

    PubMed

    Micklewright, Dominic; Parry, David; Robinson, Tracy; Deacon, Greg; Renfree, Andrew; St Clair Gibson, Alan; Matthews, William J

    2015-05-01

    The objective of this study is to examine risk taking and risk perception associations with perceived exertion, pacing, and performance in athletes. Two experiments were conducted in which risk perception was assessed using the domain-specific risk taking (DOSPERT) scale in 20 novice cyclists (experiment 1) and 32 experienced ultramarathon runners (experiment 2). In experiment 1, participants predicted their pace and then performed a 5-km maximum effort cycling time trial on a calibrated Kingcycle mounted bicycle. Split times and perceived exertion were recorded every kilometer. In experiment 2, each participant predicted their split times before running a 100-km ultramarathon. Split times and perceived exertion were recorded at seven checkpoints. In both experiments, higher and lower risk perception groups were created using median split of DOSPERT scores. In experiment 1, pace during the first kilometer was faster among lower risk perceivers compared with higher risk perceivers (t(18) = 2.0, P = 0.03) and faster among higher risk takers compared with lower risk takers (t(18) = 2.2, P = 0.02). Actual pace was slower than predicted pace during the first kilometer in both the higher risk perceivers (t(9) = -4.2, P = 0.001) and lower risk perceivers (t(9) = -1.8, P = 0.049). In experiment 2, pace during the first 36 km was faster among lower risk perceivers compared with higher risk perceivers (t(16) = 2.0, P = 0.03). Irrespective of risk perception group, actual pace was slower than predicted pace during the first 18 km (t(16) = 8.9, P < 0.001) and from 18 to 36 km (t(16) = 4.0, P < 0.001). In both experiments, there was no difference in performance between higher and lower risk perception groups. Initial pace is associated with an individual's perception of risk, with low perceptions of risk being associated with a faster starting pace. Large differences between predicted and actual pace suggest that the performance template lacks accuracy, perhaps indicating greater reliance on momentary pacing decisions rather than preplanned strategy.

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

    PubMed

    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.

  3. Carrying asymmetric loads during stair negotiation.

    PubMed

    Wang, Junsig; Gillette, Jason

    2017-03-01

    Individuals often carry items in one hand instead of both hands during activities of daily living. The combined effects of carrying asymmetric loads and stair negotiation may create even higher demands on the low back and lower extremity. The purpose of this study was to investigate the effect of symmetric and asymmetric loading conditions on L5/S1 and lower extremity moments during stair negotiation. Twenty-two college students performed stair ascent and stair descent on a three-step staircase (step height 18.5cm, tread depth 29.5cm) at preferred pace under five load conditions: no load, 10% body weight (BW) unilateral load, 20% BW unilateral load, 10% BW bilateral load, and 20% BW bilateral load. Video cameras and force platforms were used to collect kinematic and kinetic data. Inverse dynamics was used to calculate frontal plane moments for the L5/S1 and lower extremity. A 20% BW unilateral load resulted in significantly higher peak L5/S1 lateral bending, hip abduction, and external knee varus moments than nearly all other loading conditions during stair ascent and stair descent. Therefore, we suggest potential benefits when carrying symmetrical loads as compared to an asymmetric load in order to decrease the frontal joint moments, particularly at 20% BW load. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Increasing precipitation volatility in twenty-first-century California

    NASA Astrophysics Data System (ADS)

    Swain, Daniel L.; Langenbrunner, Baird; Neelin, J. David; Hall, Alex

    2018-05-01

    Mediterranean climate regimes are particularly susceptible to rapid shifts between drought and flood—of which, California's rapid transition from record multi-year dryness between 2012 and 2016 to extreme wetness during the 2016-2017 winter provides a dramatic example. Projected future changes in such dry-to-wet events, however, remain inadequately quantified, which we investigate here using the Community Earth System Model Large Ensemble of climate model simulations. Anthropogenic forcing is found to yield large twenty-first-century increases in the frequency of wet extremes, including a more than threefold increase in sub-seasonal events comparable to California's `Great Flood of 1862'. Smaller but statistically robust increases in dry extremes are also apparent. As a consequence, a 25% to 100% increase in extreme dry-to-wet precipitation events is projected, despite only modest changes in mean precipitation. Such hydrological cycle intensification would seriously challenge California's existing water storage, conveyance and flood control infrastructure.

  5. Impact of an extreme climatic event on community assembly.

    PubMed

    Thibault, Katherine M; Brown, James H

    2008-03-04

    Extreme climatic events are predicted to increase in frequency and magnitude, but their ecological impacts are poorly understood. Such events are large, infrequent, stochastic perturbations that can change the outcome of entrained ecological processes. Here we show how an extreme flood event affected a desert rodent community that has been monitored for 30 years. The flood (i) caused catastrophic, species-specific mortality; (ii) eliminated the incumbency advantage of previously dominant species; (iii) reset long-term population and community trends; (iv) interacted with competitive and metapopulation dynamics; and (v) resulted in rapid, wholesale reorganization of the community. This and a previous extreme rainfall event were punctuational perturbations-they caused large, rapid population- and community-level changes that were superimposed on a background of more gradual trends driven by climate and vegetation change. Captured by chance through long-term monitoring, the impacts of such large, infrequent events provide unique insights into the processes that structure ecological communities.

  6. Prevention of Adverse Electrical and Mechanical Remodeling with Bi-Ventricular Pacing in a Rabbit Model of Myocardial Infarction

    PubMed Central

    Saba, Samir; Mathier, Michael A.; Mehdi, Haider; Gursoy, Erdal; Liu, Tong; Choi, Bum-Rak; Salama, Guy; London, Barry

    2008-01-01

    Background: Biventricular (BIV) pacing can improve cardiac function in heart failure (HF). Objective: To investigate the mechanisms of benefit of BIV pacing using a rabbit model of myocardial infarction (MI). Methods: New Zealand White rabbits were divided into 4 groups: sham-operated (C), MI with no pacing (MI), MI with right ventricular pacing (MI+RV), and MI with BIV pacing (MI+BIV), and underwent serial electrocardiograms and echocardiograms. At 4 weeks, hearts were excised and tissue was extracted from various areas of the left ventricle (LV). Results: Four weeks after coronary ligation, BIV pacing prevented systolic and diastolic dilation of the LV as well as the reduction in its fractional shortening, restored the QRS width and the rate-dependent QT intervals to their baseline values, and prevented the decline of the ether-a-go-go (erg) protein levels. This prevention of remodeling was not documented in the MI+RV groups. Conclusions: In this rabbit model of BIV pacing and MI, we demonstrate prevention of adverse mechanical and electrical remodeling of the heart. These changes may underlie some of the benefits seen with BIV pacing in HF patients with more severe LV dysfunction. PMID:18180026

  7. The efficacy of self-paced study in multitrial learning.

    PubMed

    de Jonge, Mario; Tabbers, Huib K; Pecher, Diane; Jang, Yoonhee; Zeelenberg, René

    2015-05-01

    In 2 experiments we investigated the efficacy of self-paced study in multitrial learning. In Experiment 1, native speakers of English studied lists of Dutch-English word pairs under 1 of 4 imposed fixed presentation rate conditions (24 × 1 s, 12 × 2 s, 6 × 4 s, or 3 × 8 s) and a self-paced study condition. Total study time per list was equated for all conditions. We found that self-paced study resulted in better recall performance than did most of the fixed presentation rates, with the exception of the 12 × 2 s condition, which did not differ from the self-paced condition. Additional correlational analyses suggested that the allocation of more study time to difficult pairs than to easy pairs might be a beneficial strategy for self-paced learning. Experiment 2 was designed to test this hypothesis. In 1 condition, participants studied word pairs in a self-paced fashion without any restrictions. In the other condition, participants studied word pairs in a self-paced fashion but total study time per item was equated. The results showed that allowing self-paced learners to freely allocate study time over items resulted in better recall performance. (c) 2015 APA, all rights reserved).

  8. 42 CFR 460.102 - Interdisciplinary team.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Interdisciplinary team. 460.102 Section 460.102... ELDERLY (PACE) PACE Services § 460.102 Interdisciplinary team. (a) Basic requirement. A PACE organization must meet the following requirements: (1) Establish an interdisciplinary team at each Pace center to...

  9. 42 CFR 460.102 - Interdisciplinary team.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Interdisciplinary team. 460.102 Section 460.102... ELDERLY (PACE) PACE Services § 460.102 Interdisciplinary team. (a) Basic requirement. A PACE organization must meet the following requirements: (1) Establish an interdisciplinary team at each Pace center to...

  10. 42 CFR 460.102 - Interdisciplinary team.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Interdisciplinary team. 460.102 Section 460.102... ELDERLY (PACE) PACE Services § 460.102 Interdisciplinary team. (a) Basic requirement. A PACE organization must meet the following requirements: (1) Establish an interdisciplinary team at each Pace center to...

  11. 42 CFR 460.102 - Interdisciplinary team.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Interdisciplinary team. 460.102 Section 460.102... ELDERLY (PACE) PACE Services § 460.102 Interdisciplinary team. (a) Basic requirement. A PACE organization must meet the following requirements: (1) Establish an interdisciplinary team at each Pace center to...

  12. 42 CFR 460.102 - Interdisciplinary team.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Interdisciplinary team. 460.102 Section 460.102... ELDERLY (PACE) PACE Services § 460.102 Interdisciplinary team. (a) Basic requirement. A PACE organization must meet the following requirements: (1) Establish an interdisciplinary team at each Pace center to...

  13. Spatial resolution of pace mapping of idiopathic ventricular tachycardia/ectopy originating in the right ventricular outflow tract.

    PubMed

    Bogun, Frank; Taj, Majid; Ting, Michael; Kim, Hyungjin Myra; Reich, Stephen; Good, Eric; Jongnarangsin, Krit; Chugh, Aman; Pelosi, Frank; Oral, Hakan; Morady, Fred

    2008-03-01

    Pace mapping has been used to identify the site of origin of focal ventricular arrhythmias. The spatial resolution of pace mapping has not been adequately quantified using currently available three-dimensional mapping systems. The purpose of this study was to determine the spatial resolution of pace mapping in patients with idiopathic ventricular tachycardia or premature ventricular contractions originating in the right ventricular outflow tract. In 16 patients with idiopathic ventricular tachycardia/ectopy from the right ventricular outflow tract, comparisons and classifications of pace maps were performed by two observers (good pace map: match >10/12 leads; inadequate pace map: match < or =10/12 leads) and a customized MATLAB 6.0 program (assessing correlation coefficient and normalized root mean square of the difference (nRMSd) between test and template signals). With an electroanatomic mapping system, the correlation coefficient of each pace map was correlated with the distance between the pacing site and the effective ablation site. The endocardial area within the 10-ms activation isochrone was measured. The ablation procedure was effective in all patients. Sites with good pace maps had a higher correlation coefficient and lower nRMSd than sites with inadequate pace maps (correlation coefficient: 0.96 +/- 0.03 vs 0.76 +/- 0.18, P <.0001; nRMSd: 0.41 +/- 0.16 vs 0.89 +/- 0.39, P <.0001). Using receiver operating characteristic curves, appropriate cutoff values were >0.94 for correlation coefficient (sensitivity 81%, specificity 89%) and < or =0.54 for nRMSd (sensitivity 76%, specificity 80%). Good pace maps were located a mean of 7.3 +/- 5.0 mm from the effective ablation site and had a mean activation time of -24 +/- 7 ms. However, in 3 (18%) of 16 patients, the best pace map was inadequate at the effective ablation site, with an endocardial activation time at these sites of -25 +/- 12 ms. Pace maps with correlation coefficient > or =0.94 were confined to an area of 1.8 +/- 0.6 cm2. The 10-ms isochrone measured 1.2 +/- 0.7 cm2. The spatial resolution of a good pace map for targeting ventricular tachycardia/ectopy is 1.8 cm2 in the right ventricular outflow tract and therefore is inferior to the spatial resolution of activation mapping as assessed by isochronal activation. In approximately 20% of patients, pace mapping is unreliable in identifying the site of origin, possibly due a deeper site of origin and preferential conduction via fibers connecting the focus to the endocardial surface.

  14. Feasibility of dual-chamber (DDD) pacing via a single-pass (VDD) pacing lead employing a floating atrial ring (dipole): case series, future considerations, and refinements.

    PubMed

    Kassotis, John; Voigt, Louis; Mongwa, Mbu; Reddy, C V R

    2005-01-01

    The objective of this study was to assess the feasibility of DDD pacing from a standard single-pass VDD pacemaker system. Over the past 2 decades significant advances have been made in the development of single-pass VDD pacing systems. These have been shown in long-term prospective studies to effectively preserve atrioventricular (AV)synchrony in patients with AV block and normal sinus node function. What remains problematic is the development of a single-pass pacing system capable of DDD pacing. Such a lead configuration would be useful in those patients with peripheral venous anomalies and in younger patients with congenital anomalies, which may require lead revisions in the future. In addition, with the increased use of resynchronization (biventricular pacing) therapy, the availability of a reliable single-pass lead will minimize operative time, enhance patient safety, and minimize the amount of hardware within the heart. The feasibility of DDD pacing via a Medtronic Capsure VDD-2 (Model #5038) pacing lead was evaluated. Twenty patients who presented with AV block and normal sinus node function were recruited for this study. Atrial pacing thresholds and sensitivities were assessed intraoperatively in the supine position with various respiratory maneuvers. Five patients who agreed to participate in long-term follow-up received a dual-chamber generator and were evaluated periodically over a 12-month period. Mean atrial sensitivity was 2.35 +/- 0.83 mV at the time of implantation. Effective atrial stimulation was possible in all patients at the time of implantation (mean stimulation threshold 3.08 +/- 1.04 V at 0.5 ms [bipolar], 3.34 +/- 0.95 V at 0.5 ms [unipolar]). Five of the 20 patients received a Kappa KDR701 generator, and atrial electrical properties were followed up over a 1-year period. There was no significant change in atrial pacing threshold or incidence of phrenic nerve stimulation over the 1-year follow-up. A standard single-pass VDD pacing lead system was capable of DDD pacing intraoperatively and during long-term follow-up. Despite higher than usual thresholds via the atrial dipole, pacemaker telemetry revealed < 10% use of atrial pacing dipole over a 12-month period, which would minimally deplete the pacemaker's battery. In addition, the telemetry confirmed appropriate sensing and pacing of the atrial dipole throughout the study period. At this time such systems can serve as back-up DDD pacing systems with further refinements required to optimize atrial thresholds in all patients.

  15. Rapid behavioural gregarization in the desert locust, Schistocerca gregaria entails synchronous changes in both activity and attraction to conspecifics

    PubMed Central

    Rogers, Stephen M.; Cullen, Darron A.; Anstey, Michael L.; Burrows, Malcolm; Despland, Emma; Dodgson, Tim; Matheson, Tom; Ott, Swidbert R.; Stettin, Katja; Sword, Gregory A.; Simpson, Stephen J.

    2014-01-01

    Desert Locusts can change reversibly between solitarious and gregarious phases, which differ considerably in behaviour, morphology and physiology. The two phases show many behavioural differences including both overall levels of activity and the degree to which they are attracted or repulsed by conspecifics. Solitarious locusts perform infrequent bouts of locomotion characterised by a slow walking pace, groom infrequently and actively avoid other locusts. Gregarious locusts are highly active with a rapid walking pace, groom frequently and are attracted to conspecifics forming cohesive migratory bands as nymphs and/or flying swarms as adults. The sole factor driving the onset of gregarization is the presence of conspecifics. In several previous studies concerned with the mechanism underlying this transformation we have used an aggregate measure of behavioural phase state, Pgreg, derived from logistic regression analysis, which combines and weights several behavioural variables to characterise solitarious and gregarious behaviour. Using this approach we have analysed the time course of behavioural change, the stimuli that induce gregarization and the key role of serotonin in mediating the transformation. Following a recent critique that suggested that using Pgreg may confound changes in general activity with genuine gregarization we have performed a meta-analysis examining the time course of change in the individual behaviours that we use to generate Pgreg. We show that the forced crowding of solitarious locusts, tactile stimulation of the hind femora, and the short-term application of serotonin each induce concerted changes in not only locomotion-related variables but also grooming frequency and attraction to other locusts towards those characteristic of long-term gregarious locusts. This extensive meta-analysis supports and extends our previous conclusions that solitarious locusts undergo a rapid behavioural gregarization upon receiving appropriate stimulation for a few hours that is mediated by serotonin, at the end of which their behaviour is largely indistinguishable from locusts that have been in the gregarious phase their entire lives. PMID:24768842

  16. Comparison of DDD versus VVIR pacing modes in elderly patients with atrioventricular block.

    PubMed

    Kılıçaslan, Barış; Vatansever Ağca, Fahriye; Kılıçaslan, Esin Evren; Kınay, Ozan; Tigen, Kürşat; Cakır, Cayan; Nazlı, Cem; Ergene, Oktay

    2012-06-01

    Dual-chamber pacing is believed to have an advantage over single-chamber ventricular pacing. The aim of this study was to determine whether elderly patients who have implanted pacemakers for complete atrioventricular block gain significant benefits from dual-chamber (DDD) pacemakers compared with single chamber ventricular (VVIR) pacemakers. This study was designed as a randomized, two-period crossover study-each pacing mode was maintained for 1 month. Thirty patients (16 men, mean age 68.87 ± 6.89 years) with implanted DDD pacemakers were submitted to a standard protocol, which included an interview, pacemaker syndrome assessment, health related quality of life (HRQoL) questionnaires assessed by an SF-36 test, 6-minute walk test (6MWT), and transthoracic echocardiographic examinations. All of these parameters were obtained on both DDD and VVIR mode pacing. Paired data were compared. HRQoL scores were similar, and 6MWT results did not differ between the two groups. VVIR pacing elicited significant enlargement of the left atrium and impaired left ventricular diastolic functions as compared with DDD pacing. Two patients reported subclinical pacemaker syndrome, but this was not statistically significant. Our study revealed that in active elderly patients with complete heart block, DDD pacing and VVIR pacing yielded similar improvements in QoL and exercise performance. However, after a short follow-up period, we noted that VVIR pacing caused significant left atrial enlargement and impaired left ventricular diastolic functions.

  17. Faster Self-paced Rate of Drinking for Alcohol Mixed with Energy Drinks versus Alcohol Alone

    PubMed Central

    Marczinski, Cecile A.; Fillmore, Mark T.; Maloney, Sarah F.; Stamates, Amy L.

    2016-01-01

    The consumption of alcohol mixed with energy drinks (AmED) has been associated with higher rates of binge drinking and impaired driving when compared to alcohol alone. However, it remains unclear why the risks of use of AmED are heightened compared to alcohol alone even when the doses of alcohol consumed are similar. Therefore, the purpose of this laboratory study was to investigate if the rate of self-paced beverage consumption was faster for a dose of AmED versus alcohol alone using a double-blind, within-subjects, placebo-controlled study design. Participants (n = 16) of equal gender who were social drinkers attended 4 separate test sessions that involved consumption of alcohol (1.97 ml/kg vodka) and energy drinks, alone and in combination. On each test day, the dose assigned was divided into 10 cups. Participants were informed that they would have a two hour period to consume the 10 drinks. After the self-paced drinking period, participants completed a cued go/no-go reaction time task and subjective ratings of stimulation and sedation. The results indicated that participants consumed the AmED dose significantly faster (by approximately 16 minutes) than the alcohol dose. For the performance task, participants’ mean reaction times were slower in the alcohol conditions and faster in the energy drink conditions. In conclusion, alcohol consumers should be made aware that rapid drinking might occur for AmED beverages thus heightening alcohol-related safety risks. The fast rate of drinking may be related to the generalized speeding of responses following energy drink consumption. PMID:27819431

  18. Universal algorithm for diagnosis of biventricular capture in patients with cardiac resynchronization therapy.

    PubMed

    Jastrzebski, Marek; Kukla, Piotr; Fijorek, Kamil; Czarnecka, Danuta

    2014-08-01

    An accurate and universal method for diagnosis of biventricular (BiV) capture using a standard 12-lead electrocardiogram (ECG) would be useful for assessment of cardiac resynchronization therapy (CRT) patients. Our objective was to develop and validate such an ECG method for BiV capture diagnosis that would be independent of pacing lead positions-a major confounder that significantly influences the morphologies of paced QRS complexes. On the basis of an evaluation of 789 ECGs of 443 patients with heart failure and various right ventricular (RV) and left ventricular (LV) lead positions, the following algorithm was constructed and validated. BiV capture was diagnosed if the QRS in lead I was predominantly negative and either V1 QRS was predominantly positive or V6 QRS was of negative onset and predominantly negative (step 1), or if QRS complex duration was <160 ms (step 2). All other ECGs were classified as loss of LV capture. The algorithm showed good accuracy (93%), sensitivity (97%), and specificity (90%) for detection of loss of LV capture. The performance of the algorithm did not differ among apical, midseptal, and outflow tract RV lead positions and various LV lead positions. LV capture leaves diagnostic hallmarks in the fused BiV QRS related to different vectors of depolarization and more rapid depolarization of the ventricles. An accurate two-step ECG algorithm for BiV capture diagnosis was developed and validated. This algorithm is universally applicable to all CRT patients, regardless of the positions of the pacing leads. ©2014 Wiley Periodicals, Inc.

  19. Symptoms of chronic fatigue syndrome/myalgic encephalopathy are not determined by activity pacing when measured by the chronic pain coping inventory.

    PubMed

    Thompson, D P; Antcliff, D; Woby, S R

    2018-03-01

    Chronic fatigue syndrome/myalgic encephalopathy (CFS/ME) is a chronic illness which can cause significant fatigue, pain and disability. Activity pacing is frequently advocated as a beneficial coping strategy, however, it is unclear whether pacing is significantly associated with symptoms in people with CFS/ME. The first aim of this study was therefore to explore the cross-sectional associations between pacing and levels of pain, disability and fatigue. The second aim was to explore whether changes in activity pacing following participation in a symptom management programme were related to changes in clinical outcomes. Cross-sectional study exploring the relationships between pacing, pain, disability and fatigue (n=114) and pre-post treatment longitudinal study of a cohort of patients participating in a symptom management programme (n=35). Out-patient physiotherapy CFS/ME service. One-hundred and fourteen adult patients with CFS/ME. Pacing was assessed using the chronic pain coping inventory. Pain was measured using a Numeric Pain Rating Scale, fatigue with the Chalder Fatigue Scale and disability with the Fibromyalgia Impact Questionnaire. No significant associations were observed between activity pacing and levels of pain, disability or fatigue. Likewise, changes in pacing were not significantly associated with changes in pain, disability or fatigue following treatment. Activity pacing does not appear to be a significant determinant of pain, fatigue or disability in people with CFS/ME when measured with the chronic pain coping index. Consequently, the utility and measurement of pacing require further investigation. Copyright © 2017 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  20. Influence of pacing site characteristics on response to cardiac resynchronization therapy.

    PubMed

    Wong, Jorge A; Yee, Raymond; Stirrat, John; Scholl, David; Krahn, Andrew D; Gula, Lorne J; Skanes, Allan C; Leong-Sit, Peter; Klein, George J; McCarty, David; Fine, Nowell; Goela, Aashish; Islam, Ali; Thompson, Terry; Drangova, Maria; White, James A

    2013-07-01

    Transmural scar occupying left ventricular (LV) pacing regions has been associated with reduced response to cardiac resynchronization therapy (CRT). However, spatial influences of lead tip delivery relative to scar at both pacing sites remain poorly explored. This study evaluated scar distribution relative to LV and right ventricular (RV) lead tip placement through coregistration of late gadolinium enhancement MRI and cardiac computed tomographic (CT) findings. Influences on CRT response were assessed by serial echocardiography. Sixty patients receiving CRT underwent preimplant late gadolinium enhancement MRI, postimplant cardiac CT, and serial echocardiography. Blinded segmental evaluations of mechanical delay, percentage scar burden, and lead tip location were performed. Response to CRT was defined as a reduction in LV end-systolic volume ≥15% at 6 months. The mean age and LV ejection fraction were 64±9 years and 25±7%, respectively. Mean scar volume was higher among CRT nonresponders for both the LV (23±23% versus 8±14% [P=0.01]) and RV pacing regions (40±32% versus 24±30% [P=0.04]). Significant pacing region scar was identified in 13% of LV pacing regions and 37% of RV pacing regions. Absence of scar in both regions was associated with an 81% response rate compared with 55%, 25%, and 0%, respectively, when the RV, LV, or both pacing regions contained scar. LV pacing region dyssynchrony was not predictive of response. Myocardial scar occupying the LV pacing region is associated with nonresponse to CRT. Scar occupying the RV pacing region is encountered at higher frequency and seems to provide a more intermediate influence on CRT response.

  1. DDD versus VVIR pacing in patients, ages 70 and over, with complete heart block.

    PubMed

    Ouali, Sana; Neffeti, Elyes; Ghoul, Karima; Hammas, Sami; Kacem, Slim; Gribaa, Rim; Remedi, Fahmi; Boughzela, Essia

    2010-05-01

    Dual-chamber pacing is believed to have an advantage over single-chamber ventricular pacing. The aim of the study was to determine whether elderly patients with implanted pacemaker for complete atrioventricular block gain significant benefit from dual-chamber (DDD) compared with single-chamber ventricular demand (VVIR). The study was designed as a double-blind randomized two-period crossover study-each pacing mode was maintained for 3 months. Thirty patients (eight men, mean age 76.5 +/- 4.3 years) with implanted PM were submitted to a standard protocol, which included an interview, functional class assessment, quality of life (QoL) questionnaires, 6-minute walk test, and transthoracic echocardiographic examinations. QoL was measured by the SF-36. All these parameters were obtained on DDD mode pacing and VVIR mode pacing. Paired data were compared. QoL was significantly different between the two groups and showed the best values in DDD. Overall, no patient preferred VVIR mode, 18 preferred DDD mode, and 12 expressed no preference. No differences in mean walking distances were observed between patients with single-chamber and dual-chamber pacing. VVI pacing elicited marked decrease in left ventricle ejection fraction and significant enlargement of the left atrium. DDD pacing resulted in significant increase of the peak systolic velocities in lateral mitral annulus and septal mitral annulus. Early diastolic velocities on both sides of mitral annulus did not change. In active elderly patients with complete heart block, DDD pacing is associated with improved quality of life and systolic ventricular function compared with VVI pacing.

  2. 42 CFR 460.186 - PACE premiums.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false PACE premiums. 460.186 Section 460.186 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE...

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

    ERIC Educational Resources Information Center

    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 environment…

  4. Unintended Outcomes of University-Community Partnerships: Building Organizational Capacity with PACE International Partners

    ERIC Educational Resources Information Center

    Lloyd, Kate; Clark, Lindie; Hammersley, Laura; Baker, Michaela; Rawlings-Sanaei, Felicity; D'ath, Emily

    2015-01-01

    Professional and Community Engagement (PACE) at Macquarie University provides experiential opportunities for students and staff to contribute to more just, inclusive and sustainable societies by engaging in activities with partner organizations. PACE International offers a range of opportunities with partners overseas. Underpinning PACE is a…

  5. Correlation of mitochondrial protein expression in complexes I to V with natural and induced forms of canine idiopathic dilated cardiomyopathy.

    PubMed

    Lopes, Rosana; Solter, Philip F; Sisson, D David; Oyama, Mark A; Prosek, Robert

    2006-06-01

    To identify qualitative and quantitative differences in cardiac mitochondrial protein expression in complexes I to V between healthy dogs and dogs with natural or induced dilated cardiomyopathy (DCM). Left ventricle samples were obtained from 7 healthy dogs, 7 Doberman Pinschers with naturally occurring DCM, and 7 dogs with DCM induced by rapid right ventricular pacing. Fresh and frozen mitochondrial fractions were isolated from the left ventricular free wall and analyzed by 2-dimensional electrophoresis. Protein spots that increased or decreased in density by 2-fold or greater between groups were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or quadrupole selecting, quadrupole collision cell, time-of-flight mass spectrometry. A total of 22 altered mitochondrial proteins were identified in complexes I to V. Ten and 12 were found in complex I and complexes II to V, respectively. Five were mitochondrial encoded, and 17 were nuclear encoded. Most altered mitochondrial proteins in tissue specimens from dogs with naturally occurring DCM were associated with complexes I and V, whereas in tissue specimens from dogs subjected to rapid ventricular pacing, complexes I and IV were more affected. In the experimentally induced form of DCM, only nuclear-encoded subunits were changed in complex I. In both disease groups, the 22-kd subunit was downregulated. Natural and induced forms of DCM resulted in altered mitochondrial protein expression in complexes I to V. However, subcellular differences between the experimental and naturally occurring forms of DCM may exist.

  6. Isolation of canine coronary sinus musculature from the atria by radiofrequency catheter ablation prevents induction of atrial fibrillation.

    PubMed

    Morita, Hiroshi; Zipes, Douglas P; Morita, Shiho T; Wu, Jiashin

    2014-12-01

    The junction between the coronary sinus (CS) musculature and both atria contributes to initiation of atrial tachyarrhythmias. The current study investigated the effects of CS isolation from the atria by radiofrequency catheter ablation on the induction and maintenance of atrial fibrillation (AF). Using an optical mapping system, we mapped action potentials at 256 surface sites in 17 isolated and arterially perfused canine atrial tissues containing the entire musculature of the CS, right atrial septum, posterior left atrium, left inferior pulmonary vein, and vein of Marshal. Rapid pacing from each site before and after addition of acetylcholine (0.5 μmol/L) was applied to induce AF. Epicardial radiofrequency catheter ablation at CS-atrial junctions isolated the CS from the atria. Rapid pacing induced sustained AF in all tissues after acetylcholine. Microreentry within the CS drove AF in 88% of preparations. Reentries associated with the vein of Marshall (29%), CS-atrial junctions (53%), right atrium (65%), and pulmonary vein (76%) (frequently with 2-4 simultaneous circuits) were additional drivers of AF. Radiofrequency catheter ablation eliminated AF in 13 tissues before acetylcholine (P<0.01) and in 5 tissues after acetylcholine. Radiofrequency catheter ablation also abbreviated the duration of AF in 12 tissues (P<0.01). CS and its musculature developed unstable reentry and AF, which were prevented by isolation of CS musculature from atrial tissue. The results suggest that CS can be a substrate of recurrent AF in patients after pulmonary vein isolation and that CS isolation might help prevent recurrent AF. © 2014 American Heart Association, Inc.

  7. Feedstock powder processing research needs for additive manufacturing development

    DOE PAGES

    Anderson, Iver E.; White, Emma M. H.; Dehoff, Ryan

    2018-02-01

    Additive manufacturing (AM) promises to redesign traditional manufacturing by enabling the ultimate in agility for rapid component design changes in commercial products and for fabricating complex integrated parts. Here, by significantly increasing quality and yield of metallic alloy powders, the pace for design, development, and deployment of the most promising AM approaches can be greatly accelerated, resulting in rapid commercialization of these advanced manufacturing methods. By successful completion of a critical suite of processing research tasks that are intended to greatly enhance gas atomized powder quality and the precision and efficiency of powder production, researchers can help promote continued rapidmore » growth of AM. Finally, other powder-based or spray-based advanced manufacturing methods could also benefit from these research outcomes, promoting the next wave of sustainable manufacturing technologies for conventional and advanced materials.« less

  8. Cross Functional Career Navigation: The Way to Broaden Your Career Options

    NASA Astrophysics Data System (ADS)

    Greenhalgh, Todd

    2000-03-01

    In today's rapid paced global environment, broadening career options for career development depends on successful cross-functional career navigation. For scientists and engineers, this means developing a diversity of skills in addition to a strong technical foundation. Fortunately, companies use cross-functional teams as one of the key tools for rapidly developing and commercializing products and services. Participation on these teams carries with it the additional benefit of allowing an individual to develop new skills, and to gain valuable expertise in areas that are critical to the growth of their company, their industry and, most importantly, their career. This talk will outline some of the important cross functional skills that can propel your career ahead and ways in which you can take charge of your career mapping and enhance your value and employability.

  9. Feedstock powder processing research needs for additive manufacturing development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Iver E.; White, Emma M. H.; Dehoff, Ryan

    Additive manufacturing (AM) promises to redesign traditional manufacturing by enabling the ultimate in agility for rapid component design changes in commercial products and for fabricating complex integrated parts. Here, by significantly increasing quality and yield of metallic alloy powders, the pace for design, development, and deployment of the most promising AM approaches can be greatly accelerated, resulting in rapid commercialization of these advanced manufacturing methods. By successful completion of a critical suite of processing research tasks that are intended to greatly enhance gas atomized powder quality and the precision and efficiency of powder production, researchers can help promote continued rapidmore » growth of AM. Finally, other powder-based or spray-based advanced manufacturing methods could also benefit from these research outcomes, promoting the next wave of sustainable manufacturing technologies for conventional and advanced materials.« less

  10. Online resources in pediatric surgery: the new era of medical information.

    PubMed

    Raigani, Siavash; Numanoglu, Alp; Schwachter, Marc; Ponsky, Todd A

    2014-08-01

    Tele-education has the potential to facilitate rapid sharing and dissemination of current research and knowledge among pediatric surgeons around the world. Classically, the exchange of surgical research occurred via national surgical conferences, articles published in peer-reviewed journals, and textbooks. The advent of Web 2.0 and the rapid pace of technologic advancement have allowed knowledge, education, and research to be exchanged online. Virtual symposiums act as online conferences where participants present and debate new research and surgical techniques in real-time web meetings. Resource libraries allow up-to-date information to be archived and viewed at the user's convenience, bypassing the need to wait long periods for paper publications. Tele-education allows pediatric surgeons to connect and share ideas around the world, while saving time and money. Georg Thieme Verlag KG Stuttgart · New York.

  11. Biodiversity increases the resistance of ecosystem productivity to climate extremes

    USDA-ARS?s Scientific Manuscript database

    It remains unclear whether biodiversity buffers ecosystems against extreme climate events, which are becoming increasingly frequent worldwide. Although early results suggested that biodiversity might provide both resistance and resilience (sensu rapid recovery) of ecosystem productivity to drought, ...

  12. Pacing for neurally mediated syncope: is placebo powerless?

    PubMed

    Brignole, M; Sutton, R

    2007-01-01

    After two recent controlled trials failed to prove superiority of cardiac pacing over placebo in patients affected by neurally mediated syncope, a widely accepted opinion is that cardiac pacing therapy is not very effective and that a strong placebo effect exists. To measure the effect of placebo pacing therapy. We compared the recurrence rate of syncope during placebo vs. no treatment in controlled trials of drug or pacing therapy. Syncope recurred in 38% of 252 patients randomized to placebo pooled from five trials vs. 34% of 881 patients randomized to no treatment pooled from eight trials. The corresponding recurrence rate with active cardiac pacing was 15% in 203 patients from six trials. Placebo is not an effective therapy for neurally mediated syncope. Different selection criteria in patients who are candidates for cardiac pacing-for example, presence, absence, or severity of the cardioinhibitory reflex may separate positive from negative trials.

  13. Effects of high-intensity resistance training on strength, mobility, balance, and fatigue in individuals with multiple sclerosis: a randomized controlled trial.

    PubMed

    Hayes, Heather A; Gappmaier, Eduard; LaStayo, Paul C

    2011-03-01

    Resistance exercise via negative, eccentrically induced work (RENEW) has been shown to be associated with improvements in strength, mobility, and balance in multiple clinical populations. However, RENEW has not been reported for individuals with multiple sclerosis (MS). Nineteen individuals with MS (8 men, 11 women; age mean = 49 ± 11 years; Expanded Disability Status Scale [EDSS] mean = 5.2 ± 0.9) were randomized into either standard exercise (STAND) or standard exercise and RENEW training (RENEW) for 3×/week for 12 weeks. Outcome measures were lower extremity strength (hip/knee flexion and extension, ankle plantar and dorsiflexion, and the sum of these individual values [sum strength]); Timed Up and Go (TUG), 10-m walk, self-selected pace (TMWSS) and maximal-pace (TMWMP), stair ascent (S-A) and descent (S-D) and 6-Minute Walk Test (6MWT), Berg Balance Scale (BBS), Fatigue Severity Scale (FSS). No significant time effects or interactions were observed for strength, TUG, TMWSS, TMWMP, or 6MWT. However, the mean difference in sum strength in the RENEW group was 38.60 (representing a 15% increase) compared to the sum strength observed in the STAND group with a mean difference of 5.58 (a 2% increase). A significant interaction was observed for S-A, S-D, and BBS as the STAND group improved whereas the RENEW group did not improve in these measures. Contrary to results in other populations, the addition of eccentric training to standard exercises did not result in significantly greater lower extremity strength gains in this group of individuals with MS. Further this training was not as effective as standard exercise alone in improving balance or the ability to ascend and descend stairs. Following data collection, reassessment of required sample size indicates we were likely underpowered to detect strength differences between groups.

  14. PACE (Revised). Resource Guide. Research & Development Series No. 240D.

    ERIC Educational Resources Information Center

    Ashmore, M. Catherine; Pritz, Sandra G.

    This resource guide contains information on the Program for Acquiring Competence in Entrepreneurship (PACE) materials, a glossary, and listings of sources of information. Introductory materials include a description of PACE, information on use of PACE materials, and objectives of the 18 units for all three levels at which they are developed. An…

  15. A Study of Instructional Methods Used in Fast-Paced Classes

    ERIC Educational Resources Information Center

    Lee, Seon-Young; Olszewski-Kubilius, Paula

    2006-01-01

    This study involved 15 secondary-level teachers who taught fast-paced classes at a university based summer program and similar regularly paced classes in their local schools in order to examine how teachers differentiate or modify instructional methods and content selections for fast-paced classes. Interviews were conducted with the teachers…

  16. Predicting Successful Completion Using Student Delay Indicators in Undergraduate Self-Paced Online Courses

    ERIC Educational Resources Information Center

    Lim, Janine M.

    2016-01-01

    Self-paced online courses meet flexibility and learning needs of many students, but skepticism persists regarding the quality and the tendency for students to procrastinate in self-paced courses. Research is needed to understand procrastination and delay patterns of students in online self-paced courses to predict successful completion and…

  17. Further evidence for the role of gap junctions in the delayed antiarrhythmic effect of cardiac pacing.

    PubMed

    Miskolczi, Gottfried; Gönczi, Márton; Kovács, Mária; Seprényi, György; Végh, Ágnes

    2015-07-01

    The objective of this study was to provide evidence that gap junctions are involved in the delayed antiarrhythmic effect of cardiac pacing. Twenty-four dogs were paced through the right ventricle (4 × 5 min, rate of 240 beats/min) 24 h prior to a 25 min occlusion of the left anterior descending coronary artery. Some of these paced dogs were infused with 50 (n = 7) or 100 μmol/L (n = 7) of the gap junction uncoupler carbenoxolone (CBX), prior to and during the occlusion. Ten sham-paced dogs, subjected only to occlusion, served as the controls. Cardiac pacing markedly reduced the number of ectopic beats and episodes of ventricular tachycardia (VT), as well the incidence of VT and ventricular fibrillation during occlusion. The changes in severity of ischaemia and tissue electrical resistance were also less marked compared with the unpaced controls. Pacing also preserved the permeability of gap junctions, the phosphorylation of connexin43, and the structural integrity of the intercalated discs. The closing of gap junctions with CBX prior to and during ischaemia markedly attenuated or even abolished these protective effects of pacing. Our results support the previous findings that gap junctions play a role in the delayed antiarrhythmic effect of cardiac pacing.

  18. Differential effects of film on preschool children's behaviour dependent on editing pace.

    PubMed

    Kostyrka-Allchorne, Katarzyna; Cooper, Nicholas R; Gossmann, Anna Maria; Barber, Katy J; Simpson, Andrew

    2017-05-01

    Evidence on how the pace of television and film editing affects children's behaviour and attention is inconclusive. We examined whether a fast-paced film affected how preschool-aged children interacted with toys. The study comprised 70 children (36 girls) aged two to four-and-a-half years who attended preschools in Essex, United Kingdom. The children were paired up and tested with either a fast- or a slow-paced film of a narrator reading a children's story. The fast-paced version had 102 camera cuts and 16 still images, and the slow-paced version had 22 camera cuts and four still images. Each dyad took part in two video-recorded free-play sessions, before and after they watched one of the specially edited four-minute films. The number of toys the children played with before and after the film sessions was recorded. Before they watched the films, the children's behaviour did not differ between the groups. However, after watching the film, the children in the fast-paced group shifted their attention between toys more frequently than the children who watched the slow-paced film. Even a brief exposure to differently paced films had an immediate effect on how the children interacted with their toys. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  19. Pacing and Self-regulation: Important Skills for Talent Development in Endurance Sports.

    PubMed

    Elferink-Gemser, Marije T; Hettinga, Florentina J

    2017-07-01

    Pacing has been characterized as a multifaceted goal-directed process of decision making in which athletes need to decide how and when to invest their energy during the race, a process essential for optimal performance. Both physiological and psychological characteristics associated with adequate pacing and performance are known to develop with age. Consequently, the multifaceted skill of pacing might be under construction throughout adolescence, as well. Therefore, the authors propose that the complex skill of pacing is a potential important performance characteristic for talented youth athletes that needs to be developed throughout adolescence. To explore whether pacing is a marker for talent and how talented athletes develop this skill in middle-distance and endurance sports, they aim to bring together literature on pacing and literature on talent development and self-regulation of learning. Subsequently, by applying the cyclical process of self-regulation to pacing, they propose a practical model for the development of performance in endurance sports in youth athletes. Not only is self-regulation essential throughout the process of reaching the long-term goal of athletic excellence, but it also seems crucial for the development of pacing skills within a race and the development of a refined performance template based on previous experiences. Coaches and trainers are advised to incorporate pacing as a performance characteristic in their talent-development programs by stimulating their athletes to reflect, plan, monitor, and evaluate their races on a regular basis to build performance templates and, as such, improve their performance.

  20. Interatrial septum pacing guided by three-dimensional intracardiac echocardiography.

    PubMed

    Szili-Torok, Tamas; Kimman, Geert Jan P; Scholten, Marcoen F; Ligthart, Jurgen; Bruining, Nico; Theuns, Dominic A M J; Klootwijk, Peter J; Roelandt, Jos R T C; Jordaens, Luc J

    2002-12-18

    Currently, the interatrial septum (IAS) pacing site is indirectly selected by fluoroscopy and P-wave analysis. The aim of the present study was to develop a novel approach for IAS pacing using intracardiac echocardiography (ICE). Interatrial septum pacing may be beneficial for the prevention of paroxysmal atrial fibrillation. Cross-sectional images are acquired during a pull-back of the ICE transducer from the superior vena cava into the inferior vena cava by an electrocardiogram- and respiration-gated technique. Both atria are then reconstructed using three-dimensional (3D) imaging. Using an "en face" view of the IAS, the desired pacing site is selected. Following lead placement and electrical testing, another 3D reconstruction is performed to verify the final lead position. Twelve patients were included in this study. The IAS pacing was achieved in all patients including six suprafossal (SF) and six infrafossal (IF) lead locations all confirmed by 3D imaging. The mean duration times of atrial lead implantation and fluoroscopy were 70 +/- 48.9 min and 23.7 +/- 20.6 min, respectively. The IAS pacing resulted in a significant reduction of the P-wave duration as compared to sinus rhythm (98.9 +/- 19.3 ms vs. 141.3 +/- 8.6 ms; p < 0.002). The SF pacing showed a greater reduction of the P-wave duration than IF pacing (59.4 +/- 6.6 ms vs. 30.2 +/- 13.6 ms; p < 0.004). Three-dimensional ICE is a feasible tool for guiding IAS pacing.

  1. PACE4 is an important driver of ZR-75-1 estrogen receptor-positive breast cancer proliferation and tumor progression.

    PubMed

    Panet, François; Couture, Frédéric; Kwiatkowska, Anna; Desjardins, Roxane; Guérin, Brigitte; Day, Robert

    2017-08-01

    Breast cancer is the most frequent and deadly malignancy in women worldwide. Despite national screening programs combined with new treatments relapse rate remain high and new therapies are needed. From previous work, we identified PACE4, a member of the proprotein convertase (PCs) family of endoproteases, as a novel therapeutic target in prostate cancer. In the present study we asked the question if PACE4 could also be a potential target in breast cancer. In clinical samples of breast adenocarcinoma, we observed a specific overexpression of PACE4 in the estrogen-receptor (ER) positive subtype. We therefore looked for a breast cancer cell line model which would be representative and thus focused on the ZR-75-1 since it both expresses PACE4 and is estrogen-receptor positive. We compared stable knockdowns of furin, PACE4 and PC7 in the estrogen-receptor-positive cell line ZR-75-1 to evaluate their respective contribution to cell growth and tumor progression. PACE4 was the only PC displaying an impact on cell growth. A PACE4 peptide-based inhibitor (C23) was tested and shown to decrease proliferation of ZR-75-1 cells in cell based assays. C23 also had potent effects of tumor progression in vivo on xenografts of the ZR-75-1 cell line in athymic nude mice. Thus, PACE4-silencing and systemic administration of a PACE4 inhibitor resulted in hindered tumor progression with reduction in proliferative indices and increased cell quiescence assessed with biomarkers. Our results suggest that PACE4 is a promising target for estrogen-receptor-positive breast cancer. Copyright © 2017 Elsevier GmbH. All rights reserved.

  2. Impact of high-grade Atrioventricular block and cumulative frequent pacing on atrial arrhythmias.

    PubMed

    Wali, Eisha; Deshmukh, Amrish; Bukari, Abdallah; Broman, Michael; Aziz, Zaid; Beaser, Andrew; Upadhyay, Gaurav; Nayak, Hemal M; Tung, Roderick; Ozcan, Cevher

    2018-06-21

    The relationship between high-grade AV block (HGAVB) with cumulative frequent pacing and risk of atrial arrhythmias (AAs) has not been well characterized. We hypothesized HGAVB and pacing may have significant impact on incidence and prevalence of AAs by modulating atrial substrate. To determine impact of HGAVB and pacing on AAs including atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia (AT). All consecutive patients who underwent dual chamber pacemaker implantation for HGAVB from 2005 to 2011 at the University of Chicago were included. AAs and percent of pacing were detected through device interrogation. Patients' data were collected from electronic medical records and clinic visits. A total of 166 patients (mean age 71±15 years; 54% female, 56% African-American) were studied. AF was documented in 27% of patients before pacemaker implantation. During a mean 5.8±2.2 years of follow-up, 47% had device-detected AF, 10% AFL and 26% AT. New-onset AF was documented in 40 of the 122 patients without prior AF (33%). Continuous (≥99%) right ventricular pacing was associated with significantly decreased AF prevalence (34% versus 59%, p = 0.005), and correlated with lower incidence (26% versus 41%, p = 0.22). Pacing suppressed AF in 14% of patients with baseline AF; those patients had lower atrial pacing (3.2% versus 45%, p < 0.0001). Left atrial dilation was the only independent predictor of AF with frequent pacing (p = 0.009). HGAVB is associated with high incidence and prevalence of AAs with and without pacing. Cumulative frequent (≥99%) ventricular pacing reduces risk of AF in patients with HGAVB. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  3. Prevalence of conduction delay of the right atrium in patients with SSS: implications for pacing site selection.

    PubMed

    Verlato, Roberto; Zanon, Francesco; Bertaglia, Emanuele; Turrini, Pietro; Baccillieri, Maria Stella; Baracca, Enrico; Bongiorni, Maria Grazia; Zampiero, Aldo; Zonzin, Pietro; Pascotto, Pietro; Venturini, Diego; Corbucci, Giorgio

    2007-09-01

    To evaluate the prevalence of severe right atrial conduction delay in patients with sinus node dysfunction (SND) and atrial fibrillation (AF) and the effects of pacing in the right atrial appendage (RAA) and in the inter-atrial septum (IAS). Forty-two patients (15 male, 72 +/- 7 years) underwent electrophysiologic study to measure the difference between the conduction time from RAA to coronary sinus ostium during stimulation at 600 ms and after extrastimulus (DeltaCTos). Patients were classified as group A if DeltaCTos > 60 ms and group B if < 60 ms. Each Group was randomized to RAA/IAS pacing and algorithms ON/OFF. Fifteen patients (36%, group A) had DeltaCTos = 76 +/- 11 ms and 27 patients (64%, group B) had DeltaCTos = 36 +/- 20 ms. Twenty-two patients were paced at the RAA and 20 at the IAS. During the study, no AF recurrences were reported in 11 of 42 (26%) patients, independently of RAA or IAS pacing. Patients from group A and RAA pacing had 0.79 +/- 0.81 episodes of AF/day during DDD, which increased to 1.52 +/- 1.41 episodes of AF/day during DDDR + Alg (P = 0.046). Those with IAS pacing had 0.5 +/- 0.24 episodes of AF/day during DDD, which decreased to 0.06 +/- 0.08 episodes of AF/day during DDDR + Alg (P = 0.06). In group B, no differences were reported between pacing sites and pacing modes. Severe right atrial conduction delay is present in one-third of patients with SND and AF: continuous pacing at the IAS is superior to RAA for AF recurrences. In patients without severe conduction delay, no differences between pacing site or mode were observed.

  4. Is there a right place to pace the right ventricle? Evaluation of apical and septal positions in a pacemaker population: study protocol for a prospective intervention-control trial.

    PubMed

    Muto, Carmine; Calvi, Valeria; Botto, Giovanni Luca; Pecora, Domenico; Ciaramitaro, Gianfranco; Valsecchi, Sergio; Malacrida, Maurizio; Maglia, Giampiero

    2014-11-01

    The main objective of research in pacemaker therapy has been to provide the best physiologic way to pace the heart. Despite the good results provided by right ventricular pacing minimization and by biventricular pacing in specific subsets of heart failure patients, these options present many limitations for standard pacemaker recipients. In these patients, pacing the right ventricle at alternative sites could result in a lower degree of left intraventricular dyssynchrony. Despite the lack of strong evidence and the difficulty in placing and accurately classifying the final lead position, pacing at alternative right ventricular sites seems to have become a standard procedure at many implanting centers. The RIGHT PACE study is a multi-center, prospective, single-blind, double-arm, intervention-control trial comparing right ventricular pacing from the apex and from the septal site in terms of left intraventricular dyssynchrony. A total of 408 patients with indications for cardiac pacing but without indications for ICD and/or CRT will be enrolled. Investigators will be divided on the basis of their prior experience of selective site pacing lead implantation and patients will be treated according to the clinical practice of the centers. After device implantation, they will be followed up for 24 months through evaluation of clinical, echocardiographic and safety/system-performance variables. This study might provide important information about the impact of the right ventricular pacing on the left ventricular dyssynchrony, and about acute and chronic responses to selective site pacing, as adopted in current clinical practice. This trial is registered at ClinicalTrials.gov (ID:NCT01647490). Right Ventricular Lead Placement in a Pacemaker Population: Evaluation of apical and alternative position. ClinicalTrials.gov: NCT01647490. Copyright © 2014 Elsevier Inc. All rights reserved.

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

    PubMed

    Russell, Stuart J; Tan, Christine; O'Keefe, Peter; Ashraf, Saeed; Zaidi, Afzal; Fraser, Alan G; Yousef, Zaheer R

    2012-02-20

    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. 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 taken in the following pacing modes: atrial inhibited; right ventricular only; atrial synchronous-right ventricular; atrial synchronous-left ventricular and biventricular pacing. Optimisation of the atrioventricular and interventricular delay will be performed in the biventricular pacing group at 18 hours. The effect of biventricular pacing on myocardial injury, post operative arrhythmias and renal function will also be quantified. ClinicalTrials.gov: NCT01027299.

  6. Pacing, Pixels, and Paper: Flexibility in Learning Words from Flashcards

    ERIC Educational Resources Information Center

    Sage, Kara; Rausch, Joseph; Quirk, Abigail; Halladay, Lauren

    2016-01-01

    The present study focused on how self-control over pace might help learners successfully extract information from digital learning aids. Past research has indicated that too much control over pace can be overwhelming, but too little control over pace can be ineffective. Within the popular self-testing domain of flashcards, we sought to elucidate…

  7. Effects of Modality and Pace on Achievement, Mental Effort, and Positive Affect in Multimedia Learning Environments

    ERIC Educational Resources Information Center

    Izmirli, Serkan; Kurt, Adile Askim

    2016-01-01

    The purpose of the study was to examine the effects of instruction given with different multimedia modalities (written text + animation or narration + animation) on the academic achievement, cognitive load, and positive affect in different paces (learner-paced or system-paced); 97 freshmen university students divided into four groups taught in…

  8. Minimal invasive epicardial lead implantation: optimizing cardiac resynchronization with a new mapping device for epicardial lead placement.

    PubMed

    Maessen, J G; Phelps, B; Dekker, A L A J; Dijkman, B

    2004-05-01

    To optimize resynchronization in biventricular pacing with epicardial leads, mapping to determine the best pacing site, is a prerequisite. A port access surgical mapping technique was developed that allowed multiple pace site selection and reproducible lead evaluation and implantation. Pressure-volume loops analysis was used for real time guidance in targeting epicardial lead placement. Even the smallest changes in lead position revealed significantly different functional results. Optimizing the pacing site with this technique allowed functional improvement up to 40% versus random pace site selection.

  9. The effects of husbandry training on stereotypic pacing in captive African wild dogs (Lycaon pictus).

    PubMed

    Shyne, Amanda; Block, Martin

    2010-01-01

    To examine the effects of operant conditioning on stereotypic pacing in 3 female African wild dogs located at the Franklin Park Zoo in Boston, this study made recordings of pacing behavior immediately following individual sessions of husbandry training and 2 no-training conditions. The study found significant differences in the percentage of observations spent in stereotypic pacing behaviors for all 3 dogs among the 3 different conditions. The authors discuss the data in terms of the contribution of motivated tasks to the effects and the role of food deprivation in the expression of stereotypic pacing. The study suggests that even short periods of training may improve the African wild dogs' welfare by reducing stereotypic pacing following the conditioning sessions.

  10. Evaluation, management and prevention of lower extremity youth ice hockey injuries

    PubMed Central

    Popkin, Charles A; Schulz, Brian M; Park, Caroline N; Bottiglieri, Thomas S; Lynch, T Sean

    2016-01-01

    Ice hockey is a fast-paced sport played by increasing numbers of children and adolescents in North America and around the world. Requiring a unique blend of skill, finesse, power and teamwork, ice hockey can become a lifelong recreational activity. Despite the rising popularity of the sport, there is ongoing concern about the high frequency of musculoskeletal injury associated with participation in ice hockey. Injury rates in ice hockey are among the highest in all competitive sports. Numerous research studies have been implemented to better understand the risks of injury. As a result, rule changes were adopted by the USA Hockey and Hockey Canada to raise the minimum age at which body checking is permitted to 13–14 years (Bantam level) from 11–12 years (Pee Wee). Continuing the education of coaches, parents and players on rules of safe play, and emphasizing the standards for proper equipment use are other strategies being implemented to make the game safer to play. The objective of this article was to review the evaluation, management and prevention of common lower extremity youth hockey injuries. PMID:27920584

  11. Evaluation, management and prevention of lower extremity youth ice hockey injuries.

    PubMed

    Popkin, Charles A; Schulz, Brian M; Park, Caroline N; Bottiglieri, Thomas S; Lynch, T Sean

    2016-01-01

    Ice hockey is a fast-paced sport played by increasing numbers of children and adolescents in North America and around the world. Requiring a unique blend of skill, finesse, power and teamwork, ice hockey can become a lifelong recreational activity. Despite the rising popularity of the sport, there is ongoing concern about the high frequency of musculoskeletal injury associated with participation in ice hockey. Injury rates in ice hockey are among the highest in all competitive sports. Numerous research studies have been implemented to better understand the risks of injury. As a result, rule changes were adopted by the USA Hockey and Hockey Canada to raise the minimum age at which body checking is permitted to 13-14 years (Bantam level) from 11-12 years (Pee Wee). Continuing the education of coaches, parents and players on rules of safe play, and emphasizing the standards for proper equipment use are other strategies being implemented to make the game safer to play. The objective of this article was to review the evaluation, management and prevention of common lower extremity youth hockey injuries.

  12. Rapid Fabrication of Lightweight SiC Optics using Reactive Atom Plasma (RAP) Processing

    NASA Technical Reports Server (NTRS)

    Fiske, Peter S.

    2006-01-01

    Reactive Atom Plasma (RAP) processing is a non-contact, plasma-based processing technology that can be used to generate damage-free optical surfaces. We have developed tools and processes using RAP that allow us to shape extremely lightweight mirror Surfaces made from extremely hard-to-machine materials (e.g. SiC). We will describe our latest results using RAP in combination with other technologies to produce finished lightweight SiC mirrors and also discuss applications for RAP in the rapid fabrication of mirror segments for reflective and grazing incidence telescopes.

  13. Characterizing Urban Household Waste Generation and Metabolism Considering Community Stratification in a Rapid Urbanizing Area of China.

    PubMed

    Xiao, Lishan; Lin, Tao; Chen, Shaohua; Zhang, Guoqin; Ye, Zhilong; Yu, Zhaowu

    2015-01-01

    The relationship between social stratification and municipal solid waste generation remains uncertain under current rapid urbanization. Based on a multi-object spatial sampling technique, we selected 191 households in a rapidly urbanizing area of Xiamen, China. The selected communities were classified into three types: work-unit, transitional, and commercial communities in the context of housing policy reform in China. Field survey data were used to characterize household waste generation patterns considering community stratification. Our results revealed a disparity in waste generation profiles among different households. The three community types differed with respect to family income, living area, religious affiliation, and homeowner occupation. Income, family structure, and lifestyle caused significant differences in waste generation among work-unit, transitional, and commercial communities, respectively. Urban waste generation patterns are expected to evolve due to accelerating urbanization and associated community transition. A multi-scale integrated analysis of societal and ecosystem metabolism approach was applied to waste metabolism linking it to particular socioeconomic conditions that influence material flows and their evolution. Waste metabolism, both pace and density, was highest for family structure driven patterns, followed by lifestyle and income driven. The results will guide community-specific management policies in rapidly urbanizing areas.

  14. On being a scientist in a rapidly changing world.

    PubMed

    Mandel, I D

    1996-02-01

    The practice of biological science has changed dramatically since mid-century, reshaped not only by a rapid series of landmark discoveries, but also by governmental directives, institutional policies, and public attitudes. Until 1964, the major influences were the mentor, who provided direction and indoctrination into the culture of science, and in dentistry, the newly established NIDR, which fueled the research engine with an expanding research and training program. The 1965-74 period witnessed the advent of the Institutional Review Board, an increased social involvement of biological scientists, and a recognition of the need for biological and physical safeguards in the conduct of research. The most turbulent years were 1975-89, when there was a confluence of animal rights activism and regulation, growing concerns with scientific fraud and publication malpractice, and the stresses and strains (and opportunities) resulting from the rapid expansion of the academic-industrial complex. The current period is characterized by rapid pace, high volume, and an increased depth and breadth of knowledge-a major change in scale in the conduct of science. It is an exciting time but one in which ethical issues are multiplying. Attention must be paid.

  15. Selenium and selenocysteine: roles in cancer, health and development

    PubMed Central

    Hatfield, Dolph L.; Tsuji, Petra A.; Carlson, Bradley A.; Gladyshev, Vadim N.

    2014-01-01

    The many biological and biomedical effects of selenium are relatively unknown outside the selenium field. This fascinating element, initially described as a toxin, was subsequently shown to be essential for health and development. By the mid 1990s, selenium emerged as one of the most promising cancer chemopreventive agents, but subsequent human clinical trials yielded contradictory results. However, basic research on selenium continued to move at a rapid pace elucidating its many roles in health, development, and cancer prevention and promotion. Dietary selenium acts principally through selenoproteins, most of which are oxidoreductases involved in diverse cellular functions. PMID:24485058

  16. Research methodology in Dentistry: Part I – The essentials and relevance of research

    PubMed Central

    Krithikadatta, Jogikalmat

    2012-01-01

    The need for scientific evidence should be the basis of clinical practice. The field of restorative dentistry and endodontics is evolving at a rapid pace, with the introduction of several materials, instruments, and equipments. However, there is minimal information of their relevance in clinical practice. On the one hand, material and laboratory research is critical, however; its translation into clinical practice is not being substantiated enough with clinical research. This four part review series focuses on methods to improve evidence-based practice, by improving methods to integrate laboratory and clinical research. PMID:22368327

  17. Experience-based consulting: the value proposition.

    PubMed

    Pliner, Nicole; Thrall, James; Boland, Giles; Palumbo, Denise

    2004-11-01

    Consulting is a profession universally accepted and well entrenched throughout the business world. Whether it is providing objective analysis, supplying a specific expertise, managing a project, or simply adding extra manpower, consultants can add value. However, what are the attributes of a good consultant? In health care, with the rapid pace of emerging technologies, economic intricacies, and the complexities of clinical care, hands-on experience is the key. Recognizing the power of consultants with hands-on experience, the Department of Radiology at Massachusetts General Hospital launched the Radiology Consulting Group, an "experience-based" model for consulting that may potentially shift the profession's paradigm.

  18. Second Conference on NDE for Aerospace Requirements

    NASA Technical Reports Server (NTRS)

    Woodis, Kenneth W. (Compiler); Bryson, Craig C. (Compiler); Workman, Gary L. (Compiler)

    1990-01-01

    Nondestructive evaluation and inspection procedures must constantly improve rapidly in order to keep pace with corresponding advances being made in aerospace material and systems. In response to this need, the 1989 Conference was organized to provide a forum for discussion between the materials scientists, systems designers, and NDE engineers who produce current and future aerospace systems. It is anticipated that problems in current systems can be resolved more quickly and that new materials and structures can be designed and manufactured in such a way as to be more easily inspected and to perform reliably over the life cycle of the system.

  19. Enabling Technologies for the Future of Chemical Synthesis

    PubMed Central

    2016-01-01

    Technology is evolving at breakneck pace, changing the way we communicate, travel, find out information, and live our lives. Yet chemistry as a science has been slower to adapt to this rapidly shifting world. In this Outlook we use highlights from recent literature reports to describe how progresses in enabling technologies are altering this trend, permitting chemists to incorporate new advances into their work at all levels of the chemistry development cycle. We discuss the benefits and challenges that have arisen, impacts on academic–industry relationships, and future trends in the area of chemical synthesis. PMID:27163040

  20. The emergence and pitfalls of international tissue banking.

    PubMed

    Phillips, Glyn O

    2018-05-23

    The rapid growth of tissue banking and associated international organisations following the fall of the Berlin wall in 1991 is described. This surge in collaboration led to a world-wide constructive movement to use and to produce human tissues. As the years progressed industrialisation, led by the USA, improved the quality of tissue allografts but led higher costs and consolidation within the developing industry. The growth of litigation more than kept pace with the industrial progress. One landmark case is described, the outcome of which could revolutionise the current practices now applied to eliminate possible viral contamination of implanted tissue grafts.

  1. Prize for Industrial Applications of Physics Lecture: A physicist in Business

    NASA Astrophysics Data System (ADS)

    Woollam, John

    2013-03-01

    In the 1980s I inherited a famous ellipsometry laboratory. To speed up data acquisition and analysis I associated myself with creative scientists and engineers. We started a company which grew. Together we rapidly improved acquisition speed, accuracy, precision, spectral range, and types of applications. Yet, a business is much more than technology. In this talk I outline how a high-tech business functions, and illustrate the role of physicists and engineers in making a company successful. It is fast-paced, exciting, and enormously gratifying to provide quality instruments for researchers and industry.

  2. RNAi in the mouse: rapid and affordable gene function studies in a vertebrate system.

    PubMed

    Rytlewski, Julie A; Beronja, Slobodan

    2015-01-01

    The addition of RNA interference (RNAi) to the mammalian genomic toolbox has significantly expanded our ability to use higher-order models in studies of development and disease. The mouse, in particular, has benefited most from RNAi technology. Unique combinations of RNAi vectors and delivery methods now offer a broad platform for gene silencing in transgenic mice, enabling the design of new physiologically relevant models. The era of RNAi mice has accelerated the pace of genetic study and made high-throughput screens not only feasible but also affordable. © 2014 Wiley Periodicals, Inc.

  3. Risk Stratification of Future Left Ventricular Dysfunction for Patients with Indications for Right Ventricular Pacing due to Bradycardia.

    PubMed

    Ooka, Junichi; Tanaka, Hidekazu; Hatani, Yutaka; Hatazawa, Keiko; Matsuzoe, Hiroki; Shimoura, Hiroyuki; Sano, Hiroyuki; Sawa, Takuma; Motoji, Yoshiki; Mochizuki, Yasuhide; Ryo-Koriyama, Keiko; Matsumoto, Kensuke; Fukuzawa, Koji; Hirata, Ken-Ichi

    2017-10-21

    Although right ventricular (RV) pacing is the only effective treatment for patients with symptomatic bradycardia, it creates left ventricular (LV) dyssynchrony, which can induce LV dysfunction and heart failure. The current criterion for consideration of cardiac resynchronization therapy (CRT) is LV ejection fraction (LVEF) ≤ 35%, but indication for CRT in patients required for RV pacing with LVEF > 35% remains unclear.We studied 40 patients, all LVEF ≥ 35%, who had undergone implantable cardioverter-defibrillator implantation with RV pacing < 5%. Echocardiography was performed at baseline and during RV pacing. LV dyssynchrony was defined as anteroseptal-to-posterior wall delay from the mid-LV short-axis view using two-dimensional speckle-tracking radial strain (significant: ≥ 130 ms). Patients were divided into two groups based on baseline LVEF: normal LVEF ( ≥ 50%; n = 20) and mildly reduced LVEF (35-50%; n = 20).LVEF and LV dyssynchrony in patients with mildly reduced LVEF deteriorated significantly during RV pacing compared to those in patients with normal LVEF. Moreover, changes in LV dyssynchrony during RV pacing significantly correlated with changes in LVEF (r = -0.44, P < 0.01). Multivariate logistic regression analysis showed that baseline LVEF was the only independent predictor and baseline LVEF < 48% predictive of significant LV dyssynchrony during RV pacing.The extent of RV pacing-induced LV dysfunction may be associated with baseline LV function. These adverse effects on patients with mildly reduced LVEF of 35-50% and indications for RV pacing due to bradycardia can thus be prevented by CRT.

  4. Right atrial pacing impairs cardiac function during resynchronization therapy: acute effects of DDD pacing compared to VDD pacing.

    PubMed

    Bernheim, Alain; Ammann, Peter; Sticherling, Christian; Burger, Peter; Schaer, Beat; Brunner-La Rocca, Hans Peter; Eckstein, Jens; Kiencke, Stephanie; Kaiser, Christoph; Linka, Andre; Buser, Peter; Pfisterer, Matthias; Osswald, Stefan

    2005-05-03

    We aimed to compare the hemodynamic effects of right-atrial-paced (DDD) and right-atrial-sensed (VDD) biventricular paced rhythm on cardiac resynchronization therapy (CRT). Cardiac resynchronization therapy improves hemodynamics in patients with severe heart failure and left ventricular (LV) dyssynchrony. However, the impact of active right atrial pacing on resynchronization therapy is unknown. Seventeen CRT patients were studied 10 months (range: 1 to 46 months) after implantation. At baseline, the programmed atrioventricular delay was optimized by timing LV contraction properly at the end of atrial contraction. In both modes the acute hemodynamic effects were assessed by multiple Doppler echocardiographic parameters. Compared to DDD pacing, VDD pacing resulted in much better improvement of intraventricular dyssynchrony assessed by the septal-to-posterior wall motion delay (VDD 106 +/- 83 ms vs. DDD 145 +/- 95 ms; p = 0.001), whereas the interventricular mechanical delay (difference between onset of pulmonary and aortic outflow) did not differ (VDD 20 +/- 21 ms vs. DDD 18 +/- 17 ms; p = NS). Furthermore, VDD pacing significantly prolonged the rate-corrected LV filling period (VDD 458 +/- 123 ms vs. DDD 371 +/- 94 ms; p = 0.0001) and improved the myocardial performance index (VDD 0.60 +/- 0.18 vs. DDD 0.71 +/- 0.23; p < 0.01). Our findings suggest that avoidance of right atrial pacing results in a higher degree of LV resynchronization, in a substantial prolongation of the LV filling period, and in an improved myocardial performance. Thus, the VDD mode seems to be superior to the DDD mode in CRT patients.

  5. Pacing: a concept analysis of the chronic pain intervention.

    PubMed

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

    2013-01-01

    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 management program, outcome research is hindered by a lack of a clear and shared definition of this currently ill-defined construct. To conduct a formal concept analysis of the term 'pacing'. A standardized concept analysis process (including literature scoping to identify all uses of the concept, analysis to determine defining attributes of the concept and identification of model, borderline and contrary cases) was used to determine what the concept of pacing does and does not represent within the current evidence base. A conceptual model including the core attributes of action, time, balance, learning and self-management emerged. From these attributes, an evidence-based definition for pacing was composed and distributed to stakeholders for review. After consideration of stakeholder feedback, the emergent definition of pacing was finalized as follows: "Pacing is an active self-management strategy whereby individuals learn to balance time spent on activity and rest for the purpose of achieving increased function and participation in meaningful activities". The findings of the present concept analysis will help to standardize the use and definition of the term pacing across disciplines for the purposes of both pain management and research.

  6. A Closer Look at Split Visual Attention in System- and Self-Paced Instruction in Multimedia Learning

    ERIC Educational Resources Information Center

    Schmidt-Weigand, Florian; Kohnert, Alfred; Glowalla, Ulrich

    2010-01-01

    Two experiments examined visual attention distribution in learning from text and pictures. Participants watched a 16-step multimedia instruction on the formation of lightning. In Experiment 1 (N=90) the instruction was system-paced (fast, medium, slow pace), while it was self-paced in Experiment 2 (N=31). In both experiments the text modality was…

  7. Helping Girls Get Back on Track: An Implementation Study of the PACE Center for Girls

    ERIC Educational Resources Information Center

    Treskon, Louisa; Millenky, Megan; Freedman, Lily

    2017-01-01

    PACE Center for Girls is a unique program that provides academic and social services to girls ages 11 to 18. Girls eligible for PACE exhibit multiple health, safety, and delinquency risk factors, such as poor academic performance, exposure to abuse or violence, truancy, risky sexual behavior, and substance abuse. PACE seeks to help them onto a…

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

    ERIC Educational Resources Information Center

    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)…

  9. 77 FR 28900 - Amended Certification Regarding Eligibility to Apply for Worker Adjustment Assistance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-16

    ... Enterprises, Inc., Fitzgerald, Georgia TA-W-81,004C Pace American Enterprises, Inc., Lebanon, Oregon TA-W-81... Enterprises, Inc., Lebanon, Oregon (TA-W- 81,004C); and Pace American Enterprises, Inc., Hurricane, Utah (TA-W...., Fitzgerald, Georgia (TA-W-81,004B), Pace American Enterprises, Inc., Lebanon, Oregon (TA-W-81,004C), Pace...

  10. The Manipulation of Pace within Endurance Sport

    PubMed Central

    Skorski, Sabrina; Abbiss, Chris R.

    2017-01-01

    In any athletic event, the ability to appropriately distribute energy is essential to prevent premature fatigue prior to the completion of the event. In sport science literature this is termed “pacing.” Within the past decade, research aiming to better understand the underlying mechanisms influencing the selection of an athlete's pacing during exercise has dramatically increased. It is suggested that pacing is a combination of anticipation, knowledge of the end-point, prior experience and sensory feedback. In order to better understand the role each of these factors have in the regulation of pace, studies have often manipulated various conditions known to influence performance such as the feedback provided to participants, the starting strategy or environmental conditions. As with all research there are several factors that should be considered in the interpretation of results from these studies. Thus, this review aims at discussing the pacing literature examining the manipulation of: (i) energy expenditure and pacing strategies, (ii) kinematics or biomechanics, (iii) exercise environment, and (iv) fatigue development. PMID:28289392

  11. Forms of work organization and associations with shoulder disorders: Results from a French working population.

    PubMed

    Bodin, Julie; Garlantézec, Ronan; Costet, Nathalie; Descatha, Alexis; Fouquet, Natacha; Caroly, Sandrine; Roquelaure, Yves

    2017-03-01

    The aim of this study was to identify forms of work organization in a French region and to study associations with the occurrence of symptomatic and clinically diagnosed shoulder disorders in workers. Workers were randomly included in this cross-sectional study from 2002 to 2005. Sixteen organizational variables were assessed by a self-administered questionnaire: i.e. shift work, job rotation, repetitiveness of tasks, paced work/automatic rate, work pace dependent on quantified targets, permanent controls or surveillance, colleagues' work and customer demand, and eight variables measuring decision latitude. Five forms of work organization were identified using hierarchical cluster analysis (HCA) of variables and HCA of workers: low decision latitude with pace constraints, medium decision latitude with pace constraints, low decision latitude with low pace constraints, high decision latitude with pace constraints and high decision latitude with low pace constraints. There were significant associations between forms of work organization and symptomatic and clinically-diagnosed shoulder disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Optimal pacing for right ventricular and biventricular devices: minimizing, maximizing, and right ventricular/left ventricular site considerations.

    PubMed

    Gillis, Anne M

    2014-10-01

    The results from numerous clinical studies provide guidance for optimizing outcomes related to RV or biventricular pacing in the pacemaker and ICD populations. (1) Programming algorithms to minimize RV pacing is imperative in patients with dual-chamber pacemakers who have intrinsic AV conduction or intermittent AV conduction block. (2) Dual-chamber ICDs should be avoided in candidates without an indication for bradycardia pacing. (3) Alternate RV septal pacing sites may be considered at the time of pacemaker implantation. (4) Biventricular pacing may be beneficial in some patients with mild LV dysfunction. (5) LV lead placement at the site of latest LV activation is desirable. (6) Programming CRT systems to achieve biventricular/LV pacing >98.5% is important. (7) Protocols for AV and VV optimization in patients with CRT are not recommended after device implantation but may be considered for CRT nonresponders. (8) Novel algorithms to maximize the benefit of CRT are in evolution further.

  13. The future of discovery chemistry: quo vadis? Academic to industrial--the maturation of medicinal chemistry to chemical biology.

    PubMed

    Hoffmann, Torsten; Bishop, Cheryl

    2010-04-01

    At Roche, we set out to think about the future role of medicinal chemistry in drug discovery in a project involving both Roche internal stakeholders and external experts in drug discovery chemistry. To derive a coherent strategy, selected scientists were asked to take extreme positions and to derive two orthogonal strategic options: chemistry as the traditional mainstream science and chemistry as the central entrepreneurial science. We believe today's role of medicinal chemistry in industry has remained too narrow. To provide the innovation that industry requires, medicinal chemistry must play its part and diversify at pace with our increasing understanding of chemical biology and network pharmacology. 2010 Elsevier Ltd. All rights reserved.

  14. 42 CFR 460.162 - Voluntary disenrollment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.162 Voluntary disenrollment. A PACE...

  15. 42 CFR 460.162 - Voluntary disenrollment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.162 Voluntary disenrollment. A PACE...

  16. [Management of surgery patients with implanted cardiac pacemakers].

    PubMed

    Ugljen, R; Dadić, D; Ferek-Petrić, B; Jelić, I; Letica, D; Anić, D; Husar, J

    1995-01-01

    Patients having cardiac pacemaker implanted may be subjected to various general surgery procedures. Application of electrosurgery for the purpose of resection and coagulation, provides a high frequency electric field which produces electric voltage on the electrodes of the pacing system. This voltage may be detected within the pacing system, and various arrhythmias can be provoked in correlation with underlying rhythm and mode of pacing. Preoperative patient control and proper pacemaker programming can prevent the pacing malfunctions due to the electrosurgery application. Appropriate positioning of the neutral electrode in relation to the pacing system avoids the electric fields intersection and decreases their interference.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Saha, Devashree

    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.

  18. Bachmann bundle pacing reduces atrial electromechanical delay in type 1 myotonic dystrophy patients.

    PubMed

    Russo, Vincenzo; Rago, Anna; Papa, Andrea Antonio; Arena, Giulia; Politano, Luisa; Nigro, Gerardo

    2018-04-01

    Atrial electromechanical delay (AEMD) is an echocardiographic parameter correlated with the onset of supraventricular arrhythmias in several clinical conditions. Inter-atrial septal pacing in the region of Bachmann's bundle (BB) has been shown to be safe and feasible in myotonic dystrophy type 1 (DM1) patients, with a low rate of sensing and pacing defects. The aim of this study was to assess the impact of temporary BB pacing compared with right atrial appendage (RAA) pacing on AEMD in DM1 patients undergoing pacemaker (PM) implantation for cardiac rhythm abnormalities. The study enrolled 70 consecutive DM1 patients undergoing PM implantation for cardiac rhythm abnormalities in accordance with the current guidelines. Seventy age- and sex-matched non-DM1 patients undergoing dual-chamber PM implantation for cardiac rhythm abnormalities were used as controls. The atrial pacing lead was temporarily positioned in the RAA and on the right side of the inter-atrial septum in the region of Bachmann's bundle. For each site (BB and RAA), temporary atrial pacing in the AAI mode was established at 10 beats per minute above the sinus rate and a detailed trans-thoracic echocardiogram with tissue Doppler (TDI) analysis was recorded after at least 10 min of atrial pacing to evaluate AEMD. Temporary RAA pacing did not show statistically significant differences in inter-AEMD (48.2 ± 17.8 vs 50.5 ± 16.5 ms; P = 0.8), intra-left AEMD (43.3 ± 15.5 vs 44.6 ± 15.8 ms; P = 0.1), or intra-right-AEMD (14.1 ± 4.2 vs 15.4 ± 5.8 ms; P = 0.9), in comparison with sinus rhythm. Temporary BB pacing determined a significantly lower inter-AEMD (36.1 ± 17.1 vs 50.5 ± 16.5 ms; P = 0.001) and intra-left AEMD (32.5 ± 15.2 vs 44.6 ± 15.8 ms; P = 0.001) values in comparison with temporary RAA pacing. No statistically significant difference was found in intra-right AEMD (12.2 ± 4.6 vs 15.4 ± 5.8 ms; P = 0.2). In the control group, neither temporary RAA pacing nor temporary BB pacing showed statistically significant differences in inter-AEMD, intra-left AEMD, or intra-right AEMD values in comparison with sinus rhythm. In DM1 patients undergoing dual-chamber PM implantation, atrial pacing in the Bachmann bundle region is associated with significantly lower echocardiographic indices of atrial electromechanical delay (inter-AEMD and intra-left AEMD) in comparison with RAA pacing.

  19. 42 CFR 460.12 - Application requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.12 Application requirements. (a...

  20. 42 CFR 460.104 - Participant assessment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Services § 460.104 Participant assessment. (a) Initial comprehensive assessment—(1...

  1. 42 CFR 460.12 - Application requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PACE Organization Application and Waiver Process § 460.12 Application requirements. (a...

  2. The Pace of Cultural Evolution

    PubMed Central

    Perreault, Charles

    2012-01-01

    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. PMID:23024804

  3. The effect of aging on pacing strategies of cross-country skiers and the role of performance level.

    PubMed

    Nikolaidis, Pantelis Theodoros; Villiger, Elias; Rosemann, Thomas; Knechtle, Beat

    2018-01-01

    The participation of master cross-country (XC) skiers in training and competition has increased during the last decades; however, little is known yet about whether these athletes differ from their younger counterparts in aspects of performance such as pacing. Therefore, the aim of the present study was to examine the combined effect of age and performance (race time) on pacing in cross-country (XC) skiing. We analyzed all finishers ( n  = 79,722) in 'Vasaloppet' from 2012 to 2017, the largest cross-country skiing race in the world, classified according to their race time into 10 groups: 3-4 h, 4-5 h, ..., 12-13 h. A trivial main effect of sex on total pace range was observed ( p  < 0.001, η 2  = 0.002), where women (44.1 ± 10.2%) had larger total pace range than men (40.9 ± 11.8%). A large main effect of performance group on total pace range was shown ( p  < 0.001, η 2  = 0.160), where the smallest total pace range was 21.8 ± 1.9% (3-4 h group) and the largest 50.1 ± 9.9% (10-11 h group). A trivial sex×performance group interaction on total pace range was found ( p  < 0.001, η 2  = 0.001) with the largest sex difference in pacing shown in 9-10 h group. A trivial and small main effect of age was found in women ( p  < 0.001, η 2  = 0.005) and men ( p  < 0.001, η 2  = 0.011), respectively, where the masters had smaller total pace range than their younger counterparts. A trivial age group×performance group interaction on total pace range was observed in both women ( p  < 0.001, η 2  = 0.008) and men ( p  < 0.001, η 2  = 0.006) with smaller differences among age groups in the faster performance groups. In summary, master XC skiers adopted a relatively even pacing independently from their race time and the differences in pacing from the younger XC skiers were more pronounced in the slower masters. These findings suggest that exercise attenuates the decline of performance in master XC skiers as shown by the similar pacing strategies between fast master XC skiers and their younger counterparts.

  4. Winter storms drive rapid phenotypic, regulatory, and genomic shifts in the green anole lizard.

    PubMed

    Campbell-Staton, Shane C; Cheviron, Zachary A; Rochette, Nicholas; Catchen, Julian; Losos, Jonathan B; Edwards, Scott V

    2017-08-04

    Extreme environmental perturbations offer opportunities to observe the effects of natural selection in wild populations. During the winter of 2013-2014, the southeastern United States endured an extreme cold event. We used thermal performance, transcriptomics, and genome scans to measure responses of lizard populations to storm-induced selection. We found significant increases in cold tolerance at the species' southern limit. Gene expression in southern survivors shifted toward patterns characteristic of northern populations. Comparing samples before and after the extreme winter, 14 genomic regions were differentiated in the surviving southern population; four also exhibited signatures of local adaptation across the latitudinal gradient and implicate genes involved in nervous system function. Together, our results suggest that extreme winter events can rapidly produce strong selection on natural populations at multiple biological levels that recapitulate geographic patterns of local adaptation. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  5. Rapid changes in gene expression direct rapid shifts in intestinal form and function in the Burmese python after feeding.

    PubMed

    Andrew, Audra L; Card, Daren C; Ruggiero, Robert P; Schield, Drew R; Adams, Richard H; Pollock, David D; Secor, Stephen M; Castoe, Todd A

    2015-05-01

    Snakes provide a unique and valuable model system for studying the extremes of physiological remodeling because of the ability of some species to rapidly upregulate organ form and function upon feeding. The predominant model species used to study such extreme responses has been the Burmese python because of the extreme nature of postfeeding response in this species. We analyzed the Burmese python intestine across a time series, before, during, and after feeding to understand the patterns and timing of changes in gene expression and their relationship to changes in intestinal form and function upon feeding. Our results indicate that >2,000 genes show significant changes in expression in the small intestine following feeding, including genes involved in intestinal morphology and function (e.g., hydrolases, microvillus proteins, trafficking and transport proteins), as well as genes involved in cell division and apoptosis. Extensive changes in gene expression occur surprisingly rapidly, within the first 6 h of feeding, coincide with changes in intestinal morphology, and effectively return to prefeeding levels within 10 days. Collectively, our results provide an unprecedented portrait of parallel changes in gene expression and intestinal morphology and physiology on a scale that is extreme both in the magnitude of changes, as well as in the incredibly short time frame of these changes, with up- and downregulation of expression and function occurring in the span of 10 days. Our results also identify conserved vertebrate signaling pathways that modulate these responses, which may suggest pathways for therapeutic modulation of intestinal function in humans. Copyright © 2015 the American Physiological Society.

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

    USGS Publications Warehouse

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

    2016-01-01

    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 species had the landscape not been altered. Our study illustrates that climate change is not only a future threat, but something birds are already experiencing.

  7. The impact of MIS-3 climate events at the transition from Neanderthals to modern humans in Europe

    NASA Astrophysics Data System (ADS)

    Staubwasser, M.; Dragusin, V.; Assonov, S.; Ersek, V.; Hoffmann, D.; Veres, D.; Onac, B. P.

    2017-12-01

    We report on last glacial stable C and O isotope records from two U-Th dated speleothems from Romania. The southerly record (Ascunsa Cave, South Carpathians) from the Danube region matches the pacing and relative change in amplitude of the Greenland ice temperature record at 30-50 ka BP as well as the abundance of coastal winter sea ice in the Black Sea. The northerly record (Tausoare Cave, East Carpathians) in parts shares the pacing of events with the Greenland or the southern Romanian record, but best matches northern Black Sea summer season temperature change. Heinrich events do not stand out in either record, but the temperature amplitudes of Greenland stadials and Black Sea records are generally reproduced. Based on similarity with the Black Sea we interpret the combined two speleothem records in terms of seasonal temperature change in central Eastern Europe. A climatic influence on the transition from Neanderthals to modern humans has long been suspected. However, the diachronous and spatially complex archaeologic succession across the Middle-Upper Paleolithic (MUPL) in Europe ( 38 - 48 ka) is difficult to reconcile with the millennial-scale pacing of northern hemisphere paleoclimate. Two extreme cold events at 44.0-43.3 recorded and 40.7-39.8 ka in the speleothems bracket the dates of the first known appearance of modern humans - the Aurignacian complex - and the disappearance of Neanderthals from most of Europe. These cold events are coeval with Greenland Stadials GS-12 and GS-10. The speleothem records generally match the paleosol/loess succession from central Europe across the MUPL. The combined record suggests that permafrost advance may have made central Europe uninhabitable at least during winter. The combined paleoclimate and archaeologic records suggest that depopulation-repopulation cycles may have occurred during and after each cold event. Repopulation of central Europe geographically favored the modern human Aurignacians from SE Europe.

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

    PubMed

    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 species had the landscape not been altered. Our study illustrates that climate change is not only a future threat, but something birds are already experiencing. © 2015 John Wiley & Sons Ltd.

  9. 42 CFR 460.172 - Documentation of disenrollment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) PROGRAMS OF ALL-INCLUSIVE CARE FOR THE ELDERLY (PACE) Participant Enrollment and Disenrollment § 460.172 Documentation of disenrollment. A PACE...

  10. Helping Girls Get Back on Track: An Implementation Study of the PACE Center for Girls. Executive Summary

    ERIC Educational Resources Information Center

    Treskon, Louisa; Millenky, Megan; Freedman, Lily

    2017-01-01

    PACE Center for Girls is a unique program that provides academic and social services to girls ages 11 to 18. Girls eligible for PACE exhibit multiple health, safety, and delinquency risk factors, such as poor academic performance, exposure to abuse or violence, truancy, risky sexual behavior, and substance abuse. PACE seeks to help them onto a…

  11. Assessing the PACE of California residential solar deployment: Impacts of Property Assessed Clean Energy programs on residential solar photovoltaic deployment in California, 2010-2015

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deason, Jeff; Murphy, Sean

    A new study by Berkeley Lab found that residential Property Assessed Clean Energy (R-PACE) programs increased deployment of residential solar photovoltaic (PV) systems in California, raising it by about 7-12% in cities that adopt these programs. R-PACE is a financing mechanism that uses a voluntary property tax assessment, paid off over time, to facilitate energy improvements and, in some jurisdictions, water and resilience measures. While previous studies demonstrated that early, regional R-PACE programs increased solar PV deployment, this new analysis is the first to demonstrate these impacts from the large, statewide R-PACE programs dominating the California market today, which usemore » private capital to fund the upfront costs of the improvements. Berkeley Lab estimated the impacts using econometric techniques on two samples: -Large cities only, allowing annual demographic and economic data as control variables -All California cities, without these annual data Analysis of both samples controls for several factors other than R-PACE that would be expected to drive solar PV deployment. We infer that on average, cities with R-PACE programs were associated with greater solar PV deployment in our study period (2010-2015). In the large cities sample, solar PV deployment in jurisdictions with R-PACE programs was higher by 1.1 watts per owner-occupied household per month, or 12%. Across all cities, solar PV deployment in jurisdictions with R-PACE programs was higher by 0.6 watts per owner-occupied household per month, or 7%. The large cities results are statistically significant at conventional levels; the all-cities results are not. The estimates imply that the majority of solar PV deployment financed by R-PACE programs would likely not have occurred in their absence. Results suggest that R-PACE programs have increased PV deployment in California even in relatively recent years, as R-PACE programs have grown in market share and as alternate approaches for financing solar PV have developed. The U.S. Department of Energy’s Building Technologies Office supported this research.« less

  12. Increased base rate of atrial pacing for prevention of atrial fibrillation after implantation of a dual-chamber pacemaker: insights from the Atrial Overdrive Pacing Study.

    PubMed

    Kantharia, Bharat K; Freedman, Roger A; Hoekenga, David; Tomassoni, Gery; Worley, Seth; Sorrentino, Robert; Steinhaus, David; Wolkowicz, Joel M; Syed, Zaffer A

    2007-11-01

    Different pacing sites and various algorithms have been utilized to prevent atrial fibrillation (AF) in pacemaker recipients. However, the optimal pacing rate settings have not yet been established. In this randomized, prospective, multicentre, single-blinded, cross over study, rate-adaptive pacing at a high base rate (BR) in patients, age 60 years or above, or a history of paroxysmal AF, who underwent dual-chamber (DDD) pacemaker implantation for standard pacing indications, was evaluated for prevention of AF. In the study cohort of 145 patients implanted with DDD pacemakers with a programmable rest rate (RR) feature, the BR/RR settings were sequentially but randomly adjusted as follows: 60 bpm/Off for the baseline quarter (initial 3 months) and then to either 'A-B-C' or 'C-B-A' settings (A = 70/65 bpm, B = 70/Off, C = 80/65 bpm) for the subsequent quarters each of 3 months duration. Data on automatic mode switch episodes, device diagnostics, and a questionnaire evaluating pacemaker awareness and palpitations were collected. Ninety-nine patients, mean age 77 +/- 10 years, who completed the study protocol and followed for 12 months did not show significant differences in the number of mode switch episodes between any settings used. The percentage of atrial pacing was lower during baseline pacing compared to settings A, B, and C (P < 0.0001). Setting C produced a higher percentage of atrial pacing than A and B (P < 0.01). Although a higher percentage of atrial pacing correlated with a lower incidence of mode switch episodes, there was no statistically significant difference in the number of mode switch episodes between settings A, B, and C. There were no significant differences in the questionnaire scores relating to pacemaker awareness or palpitation. Overdrive single-site pacing in the right atrium achieved by programming analysed settings in the present study did not reduce AF as assessed by mode switch episodes. Additionally, no change in the symptoms of arrhythmia or awareness of pacing was seen.

  13. Dynamic and dual-site atrial pacing in the prevention of atrial fibrillation: The STimolazione Atrial DInamica Multisito (STADIM) Study.

    PubMed

    De Simone, Antonio; Senatore, Gaetano; Donnici, Giovanni; Turco, Pietro; Romano, Enrico; Gazzola, Carlo; Stabile, G

    2007-01-01

    The impact of new algorithms to consistently pace the atrium on the prevention of atrial fibrillation (AF) remains unclear. Our randomized, crossover study compared the efficacy of single- and dual-site atrial pacing, with versus without dynamic atrial overdrive pacing in preventing AF. We studied 72 patients (mean age = 69.6 +/- 6.5 years, 34 men) with sick sinus syndrome (SSS) and paroxysmal or persistent AF, who received dual-chamber pacemakers (PM) equipped with an AF prevention algorithm and two atrial leads placed in the right atrial appendage (RAA), by passive fixation, and in the coronary sinus ostium (CS), by active fixation, respectively. At implant, the patients were randomly assigned to unipolar CS versus RAA pacing. The PM was programmed in DDDR mode 1 month after implant. Each patient underwent four study phases of equal duration: (1) unipolar, single site (CS or RAA) pacing with the AF algorithm ON (atrial lower rate = 0 ppm); (2) unipolar, single site pacing with the AF algorithm OFF (atrial lower rate = 70 bpm); (3) bipolar, dual-site pacing with AF algorithm ON; (4) bipolar, dual-site pacing with the AF algorithm OFF. Among 40 patients (56%), who completed the follow-up (15 +/- 4 months) no difference was observed in the mean number of automatic mode switch (AMS) corrected for the duration of follow-up, in unipolar (5.6 +/- 22.8 vs 2.6 +/- 5.5) or bipolar mode (3.3 +/- 12.7 vs 2.1 +/- 4.9) with, respectively, the algorithm OFF or ON. With the AF prevention algorithm ON, the percentage of atrial pacing increased significantly from 78.7 +/- 22.1% to 92.4 +/- 4.9% (P < 0.001), while the average ventricular heart rate was significantly lower with the algorithm ON (62.4 +/- 17.5 vs 79.9 +/- 3 bpm (P < 0.001). The AF prevention algorithm increased the percentage of atrial pacing significantly, regardless of the atrial pulse configuration and pacing site, while maintaining a slower ventricular heart rate. It had no impact on the number of AMS in the unipolar and bipolar modes in patients with SSS.

  14. Curriculum evaluation and revision in a nascent field: the utility of the retrospective pretest--posttest model in a homeland security program of study.

    PubMed

    Pelfrey, William V; Pelfrey, William V

    2009-02-01

    Although most academic disciplines evolve at a measured pace, the emerging field of homeland security must, for reasons of safety and security, evolve rapidly. The Department of Homeland Security sponsored the establishment of a graduate educational program for key officials holding homeland security roles. Because homeland security is a nascent field, the establishment of a program curriculum was forced to draw from a variety of disciplines. Curriculum evaluation was complicated by the rapid changes occurring in the emerging discipline, producing response shift bias, and interfering with the pre-post assessments. To compensate for the validity threat associated with response shift bias, a retrospective pretest-posttest evaluative methodology was used. Data indicate the program has evolved in a significant and orderly fashion and these data support the use of this innovative evaluation approach in the development of any discipline.

  15. A Model Program for Translational Medicine in Epilepsy Genetics

    PubMed Central

    Smith, Lacey A.; Ullmann, Jeremy F. P.; Olson, Heather E.; El Achkar, Christelle M.; Truglio, Gessica; Kelly, McKenna; Rosen-Sheidley, Beth; Poduri, Annapurna

    2017-01-01

    Recent technological advances in gene sequencing have led to a rapid increase in gene discovery in epilepsy. However, the ability to assess pathogenicity of variants, provide functional analysis, and develop targeted therapies has not kept pace with rapid advances in sequencing technology. Thus, although clinical genetic testing may lead to a specific molecular diagnosis for some patients, test results often lead to more questions than answers. As the field begins to focus on therapeutic applications of genetic diagnoses using precision medicine, developing processes that offer more than equivocal test results is essential. The success of precision medicine in epilepsy relies on establishing a correct genetic diagnosis, analyzing functional consequences of genetic variants, screening potential therapeutics in the preclinical laboratory setting, and initiating targeted therapy trials for patients. We describe the structure of a comprehensive, pediatric Epilepsy Genetics Program that can serve as a model for translational medicine in epilepsy. PMID:28056630

  16. Tempo and mode in human evolution.

    PubMed Central

    McHenry, H M

    1994-01-01

    The quickening pace of paleontological discovery is matched by rapid developments in geochronology. These new data show that the pattern of morphological change in the hominid lineage was mosaic. Adaptations essential to bipedalism appeared early, but some locomotor features changed much later. Relative to the highly derived postcrania of the earliest hominids, the craniodental complex was quite primitive (i.e., like the reconstructed last common ancestor with the African great apes). The pattern of craniodental change among successively younger species of Hominidae implies extensive parallel evolution between at least two lineages in features related to mastication. Relative brain size increased slightly among successively younger species of Australopithecus, expanded significantly with the appearance of Homo, but within early Homo remained at about half the size of Homo sapiens for almost a million years. Many apparent trends in human evolution may actually be due to the accumulation of relatively rapid shifts in successive species. PMID:8041697

  17. Leveraging Industry-Academia Collaborations in Adaptive Biomedical Innovation.

    PubMed

    Stewart, S R; Barone, P W; Bellisario, A; Cooney, C L; Sharp, P A; Sinskey, A J; Natesan, S; Springs, S L

    2016-12-01

    Despite the rapid pace of biomedical innovation, research and development (R&D) productivity in the pharmaceutical industry has not improved broadly. Increasingly, firms need to leverage new approaches to product development and commercial execution, while maintaining adaptability to rapid changes in the marketplace and in biomedical science. Firms are also seeking ways to capture some of the talent, infrastructure, and innovation that depends on federal R&D investment. As a result, a major transition to external innovation is taking place across the industry. One example of these external innovation initiatives is the Sanofi-MIT Partnership, which provided seed funding to MIT investigators to develop novel solutions and approaches in areas of interest to Sanofi. These projects were highly collaborative, with information and materials flowing both ways. The relatively small amount of funding and short time frame of the awards built an adaptable and flexible process to advance translational science. © 2016 American Society for Clinical Pharmacology and Therapeutics.

  18. Engineered Antibodies for Monitoring of Polynuclear Aromatic Hydrocarbons

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alexander E. Karu Ph.D; Victoria A. Roberts Ph.D.; Qing X. Li, Ph.D.

    2002-01-17

    This project was undertaken to fill needs in ODE's human and ecosystem health effects research, site remediation, rapid emergency response, and regulatory compliance monitoring programs. Doe has greatly stimulated development and validation of antibody-based, rapid, field-portable detection systems for small hazardous compounds. These range from simple dipsticks, microplate enzyme-linked immunosorbent assays (ELISAs), and hand-held colorimeters, to ultrasensitive microfluidic reactors, fiber-optic sensors and microarrays that can identify multiple analytes from patterns of cross-reactivity. Unfortunately, the technology to produce antibodies with the most desirable properties did not keep pace. Lack of antibodies remains a limiting factor in production and practical use ofmore » such devices. The goals of our project were to determine the chemical and structural bases for the antibody-analyte binding interactions using advanced computational chemistry, and to use this information to create useful new binding properties through in vitro genetic engineering and combinatorial library methods.« less

  19. Rapid acquisition but slow extinction of an attentional bias in space.

    PubMed

    Jiang, Yuhong V; Swallow, Khena M; Rosenbaum, Gail M; Herzig, Chelsey

    2013-02-01

    Substantial research has focused on the allocation of spatial attention based on goals or perceptual salience. In everyday life, however, people also direct attention using their previous experience. Here we investigate the pace at which people incidentally learn to prioritize specific locations. Participants searched for a T among Ls in a visual search task. Unbeknownst to them, the target was more often located in one region of the screen than in other regions. An attentional bias toward the rich region developed over dozens of trials. However, the bias did not rapidly readjust to new contexts. It persisted for at least a week and for hundreds of trials after the target's position became evenly distributed. The persistence of the bias did not reflect a long window over which visual statistics were calculated. Long-term persistence differentiates incidentally learned attentional biases from the more flexible goal-driven attention. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  20. Effects of enhanced pacing modalities on health care resource utilization and costs in bradycardia patients: An analysis of the randomized MINERVA trial.

    PubMed

    Boriani, Giuseppe; Manolis, Antonis S; Tukkie, Raymond; Mont, Lluis; Pürerfellner, Helmut; Santini, Massimo; Inama, Giuseppe; Serra, Paolo; Gulizia, Michele; Samoilenko, Igor Vasilyevich; Wolff, Claudia; Holbrook, Reece; Gavazza, Federica; Padeletti, Luigi

    2015-06-01

    Many patients who suffer from bradycardia and need cardiac pacing also have atrial fibrillation (AF). New pacemaker algorithms, such as atrial preventive pacing and atrial antitachycardia pacing (DDDRP) and managed ventricular pacing (MVP), have been specifically designed to reduce AF occurrence and duration and to minimize the detrimental effects of right ventricular pacing. The randomized MINimizE Right Ventricular pacing to prevent Atrial fibrillation and heart failure trial established that DDDRP + MVP pacing modality reduced permanent AF in bradycardia patients as compared with standard dual-chamber pacing (DDDR). The aim of this study was to estimate the cost savings due to lower AF-related health care utilization events based on health care costs from the United States and the European Union. Dual-chamber pacemaker patients with a history of paroxysmal or persistent AF were randomly assigned to receive DDDR (n = 385) or the advanced features (DDDRP + MVP; n = 383). We used published health care costs from the United States and the European Union (Italy, Spain, and the United Kingdom) to estimate the costs associated with AF-related hospitalizations and emergency visits. The rate of AF-related hospitalizations was significantly lower in the DDDRP + MVP group than in the conventional pacemaker group (DDDR group; 42% reduction; incidence rate ratio 0.58). Similarly, a significant reduction of 68% was observed for AF-related emergency department visits (incidence rate ratio 0.32; P < .001). As a consequence, DDDRP + MVP could potentially reduce health care costs by 40%-44%. Over a ten-year period, the cost savings per 100 patients ranged from $35,702 in the United Kingdom to $121,831 in the United States. New pacing algorithms such as DDDRP + MVP used in the MINimizE Right Ventricular pacing to prevent Atrial fibrillation and heart failure trial successfully reduced AF-related health care utilization, resulting in significant cost savings to payers. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

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