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Continuous Recording (continuous + recording)
Selected AbstractsThe Use of Ultrasonic Reflectoscope for the Continuous Recording of the Movements of Heart Walls.CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 3 2004I. Edler First page of article [source] Continuous recording of accommodation and pupil size using the Shin-Nippon SRW-5000 autorefractorOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 2 2001J. S. Wolffsohn Summary A newly released commercial autorefractor, the Shin-Nippon SRW-5000 (Japan), has been found to be valid compared to subjective refraction and repeatable over a wide prescription range. Its binocular open field-of-view allows the accommodative state to be monitored while a natural environment is viewed. In conventional static mode, the device can take up to 45 readings in 1 min using digital image analysis of the reflected retinal image of a measurement ring. Continuous on-line analysis of the ring provides high (up to 60 Hz) temporal resolution of the refractive state to an accuracy of <0.001 D. Pupil size can also be analysed to a resolution of <0.001 mm. The measurement of accommodation and pupil size was relatively unaffected by eccentricity of viewing up to ±10° and instrument focusing inaccuracies of ±5 mm. The resolution properties of the analysis are shown to be ideal for measurement of dynamic accommodation and pupil responses. [source] Daily jaw muscle activity in freely moving rats measured with radio-telemetryEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2007Nobuhiko Kawai The jaw muscle activity of rats has been investigated for specific tasks. However, the daily jaw muscle use remains unclear. The purpose of the present study was to examine daily jaw muscle activity, and its variability over time, in the rat (n = 12) by the use of radio-telemetry. A telemetric device was implanted for the continuous recording of masseter muscle and digastric muscle activity. Daily muscle use was characterized by calculating the total time that each muscle was active (duty time), the number of bursts, and the average length of bursts. All parameters were estimated for activities exceeding various levels (5,90%) of the day's peak activity. Daily muscle use remained constant for 4 wk. At the low-activity level, the duty time and burst number of the digastric muscle were significantly (P < 0.01) higher than those of the masseter muscle, whereas the opposite was true at the high-activity level (P < 0.05). No significant intermuscular correlation was observed between the number of bursts of the masseter and digastric muscles, but the interindividual variation of both muscles changed, depending on the level of activation. These findings suggest that the masseter muscle and the digastric muscle show a differential active pattern, depending on the activity level. [source] Force Spectroscopic Investigations During the Local Oxidation of n -Octadecyltrichlorosilane Monolayers,ADVANCED FUNCTIONAL MATERIALS, Issue 1 2006S. Hoeppener Abstract Scanning force spectroscopy (SFS) is a powerful tool for investigating surface properties with high precision. Unlike most common spectroscopic techniques, information about local properties can also be obtained from surface areas with nanometer dimensions. This makes SFS a useful investigative tool for small lithographic structures. We apply the continuous recording of force curves to extract valuable information about the local oxidation of a monolayer of n -octadecyltrichlorosilane molecules self-assembled on silicon. The oxidation is carried out while simultaneously recording the force curves during the application of a bias voltage to the tip. The dynamics of the induced surface modifications and changes in the surface properties are followed by analyzing specific spots in the force curves. [source] Haemodynamic effects of ,75 mmHg negative pressure therapy in a porcine sternotomy wound modelINTERNATIONAL WOUND JOURNAL, Issue 1 2009Arash Mokhtari Abstract Previous research has shown ,125 mmHg to be the optimal negative pressure for creating an environment that promotes wound healing, and this has therefore been adopted as a standard pressure for patients with deep sternal wound infection. However, it has not yet been clearly shown that ,125 mmHg is the optimal pressure from a haemodynamic point of view. Furthermore, there have been reports of cardiac rupture during ,125 mmHg negative pressure therapy. We therefore studied the effects of a lower pressure: ,75 mmHg. Twelve pigs were used. After median sternotomy, sealed negative pressure therapy of ,75 mmHg was applied. Baseline measurements were made and continuous recording of the cardiac output, end-tidal CO2 production, mean arterial pressure, mean pulmonary pressure (pulmonary artery pressure), systemic vascular resistance, pulmonary vascular resistance, left atrial pressure and central venous pressure was started. Six pigs served as controls. No statistically significant difference was observed in any of the haemodynamic parameters studied, compared with the controls. The present study shows that, with a suitable foam application technique, ,75 mmHg can be applied without compromising the central haemodynamics. [source] Two decades of responses (1986,2006) to climate by the Laurichard rock glacier, French AlpsPERMAFROST AND PERIGLACIAL PROCESSES, Issue 4 2009Xavier Bodin Abstract The Laurichard active rock glacier is the permafrost-related landform with the longest record of monitoring in France, including an annual geodetic survey, repeated geoelectrical campaigns from 1979 onwards and continuous recording of ground temperature since 2003. These data were used to examine changes in creep rates and internal structure from 1986 to 2006. The control that climatic variables exert on rock glacier kinematics was investigated over three time scales. Between the 1980s and the early 2000s, the main observed changes were a general increase in surface velocity and a decrease in internal resistivity. At a multi-year scale, the high correlation between surface movement and snow thickness in the preceding December appears to confirm the importance of snow cover conditions in early winter through their influence on the ground thermal regime. A comparison of surface velocities, regional climatic datasets and ground sub-surface temperatures over six years suggests a strong relation between rock glacier deformation and ground temperature, as well as a role for liquid water due to melt of thick snow cover. Finally, unusual surface lowering that accompanied peak velocities in 2004 may be due to a general thaw of the top of the permafrost, probably caused both by two successive snowy winters and by high energy inputs during the warm summer of 2003. Copyright © 2009 John Wiley & Sons, Ltd. [source] Optimal foraging on the roof of the world: Himalayan langurs and the classical prey modelAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010Ken Sayers Abstract Optimal foraging theory has only been sporadically applied to nonhuman primates. The classical prey model, modified for patch choice, predicts a sliding "profitability threshold" for dropping patch types from the diet, preference for profitable foods, dietary niche breadth reduction as encounter rates increase, and that exploitation of a patch type is unrelated to its own abundance. We present results from a 1-year study testing these predictions with Himalayan langurs (Semnopithecus entellus) at Langtang National Park, Nepal. Behavioral data included continuous recording of feeding bouts and between-patch travel times. Encounter rates were estimated for 55 food types, which were analyzed for crude protein, lipid, free simple sugar, and fibers. Patch types were entered into the prey model algorithm for eight seasonal time periods and differing age-sex classes and nutritional currencies. Although the model consistently underestimated diet breadth, the majority of nonpredicted patch types represented rare foods. Profitability was positively related to annual/seasonal dietary contribution by organic matter estimates, whereas time estimates provided weaker relationships. Patch types utilized did not decrease with increasing encounter rates involving profitable foods, although low-ranking foods available year-round were taken predominantly when high-ranking foods were scarce. High-ranking foods were taken in close relation to encounter rates, while low-ranking foods were not. The utilization of an energetic currency generally resulted in closest conformation to model predictions, and it performed best when assumptions were most closely approximated. These results suggest that even simple models from foraging theory can provide a useful framework for the study of primate feeding behavior. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Influence of drinking method on tooth-surface pH in relation to dental erosionEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2004Ann-Katrin Johansson The aim of this investigation was to study the intraoral pH response on tooth surfaces in relation to dental erosion during and after drinking a sugar-free cola-type soft drink. Six different methods of drinking were tested in a randomized order: holding; short-sipping; long-sipping; gulping; nipping; and sucking. Two methods of pH measurement were used in two series of individuals. In the first series, pH was measured by using the microtouch method in 12 healthy adults at three dental erosion-prone sites: 11 palatally; 11 buccally; and at the mesiobuccal cusp tip of 16. In the second series, pH was measured by using the telemetric method in 6 healthy individuals, producing continuous recordings of pH by means of a glass electrode in a specified approximal area. The two series showed similar results, although the telemetric method generally recorded larger pH falls. Holding the drink in the mouth before swallowing led to the most pronounced pH drop, followed by the long-sipping method. Gulping resulted in only a small decrease of pH. No differences among the three intraoral sites were found when analyzed by using the microtouch method. The conclusion from this study is that the drinking method strongly affects tooth-surface pH and thereby the risk for dental erosion. It therefore seems appropriate to include advice on the method of drinking in dietary counseling related to dental erosion. [source] Evening Light Exposure: Implications for Sleep and DepressionJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2002Geralyn M. Wallace-Guy MA OBJECTIVES: To examine whether dim illumination in the evening is a factor in sleep disturbances of aging, depression, and circadian phase advance. DESIGN: One-week continuous recordings were made to record illumination exposure and to infer 24-hour sleep patterns from wrist activity. SETTING: Recordings took place during normal home and community activities. PARTICIPANTS: Complete data of 154 postmenopausal women, mean age 66.7, were selected from a larger study of participants in the Women's Health Initiative. MEASUREMENTS: Illumination in lux was averaged for 4 hours before bedtime and over 24 hours. Mood was measured using a brief eight-item screen. RESULTS: Illumination in the 4 hours before bedtime was quite dim: median 24 lux. Nevertheless, evening light exposure was not significantly related to sleep amount (in bed or out of bed) sleep efficiency, sleep latency, wake within sleep, or mood. In contrast, the overall amount of light throughout the 24 hours was negatively correlated with sleep latency, wake within sleep, and depressed mood. CONCLUSIONS: Low evening lighting does not appear to be a crucial factor in sleep and mood disturbances of aging, but overall lighting may contribute to these disturbances. [source] Review article: from 1906 to 2006 , a century of major evolution of understanding of gastro-oesophageal reflux diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2006J. DENT Summary Background Our understanding of gastro-oesophageal reflux disease has undergone significant changes over the last century. Aim To trace the rise in understanding of gastro-oesophageal reflux disease and highlight remaining areas of uncertainty. Methods Literature review. Results In 1906, Tileston published his observations on ,peptic ulcer of the oesophagus'. Winkelstein, in 1934, first correlated symptoms of heartburn with acid regurgitation and reflux oesophagitis. In 1946, Allison described hiatus hernia as a causal factor in the development of gastro-oesophageal reflux disease. In 1958, Bernstein and Baker showed a direct relationship between oesophageal acidification and heartburn in patients with gastro-oesophageal reflux disease, irrespective of endoscopic findings, leading to the recognition of non-erosive gastro-oesophageal reflux disease. In the 1980s, continuous recordings of the lower oesophageal sphincter showed that episodes of reflux were related to transient relaxations of lower oesophageal sphincter tone. There is now increasing recognition that gastro-oesophageal reflux disease arises from the interaction of several anatomical and physiological factors. A turning point in the medical treatment of gastro-oesophageal reflux disease came with the introduction of the first proton pump inhibitor, omeprazole, in 1989. Conclusions Future efforts need to identify the multifactorial interactions of gastro-oesophageal junction anatomy and physiology in patients with gastro-oesophageal reflux disease. Increased understanding of the disease will guide development of new therapies. [source] Interactions among peripheral perfusion, cardiac activity, oxygen saturation, thermal profile and body position in growing low birth weight infantsACTA PAEDIATRICA, Issue 1 2010R Sahni Abstract Aims:, To investigate the correlation between the ,perfusion index' (PI) and other commonly used estimates of cutaneous blood flow [heart rate (HR), surface temperatures (ST) and central-to-peripheral thermal gradients (C-P grad)] and to use this new non-invasive tool to compare differences between prone and supine sleep position in low birth weight (LBW) infants. Methods:, Six-hour continuous recordings of pulse oximetry, cardiac activity and absolute ST from three sites (flank, forearm and leg), along with minute-to-minute assessment of behavioural states were performed in 31 LBW infants. Infants were randomly assigned to the prone or supine position for the first 3 h and then reversed for the second 3 h. PI data were correlated with HR and C-P grad, and compared across sleep positions during quiet sleep (QS) and active sleep (AS). Results:, Perfusion index correlated significantly with HR (r2 = 0.40) and flank-to-forearm thermal gradient (r2 = 0.28). In the prone position during QS, infants exhibited higher PI (3.7 ± 0.9 vs. 3.1 ± 0.7), HR (158.4 ± 8.9 vs. 154.1 ± 8.8 bpm), SpO2 (95.8 ± 2.6 vs. 95.2 ± 2.6%), flank (36.7 ± 0.4 vs. 36.5 ± 0.4°C), forearm (36.1 ± 0.6 vs. 35.5 ± 0.4°C) and leg (35.4 ± 0.7 vs. 34.7 ± 0.7°C) temperatures and narrower flank-to-forearm (0.6 ± 0.4 vs. 0.9 ± 0.3°C) and flank-to-leg (1.3 ± 0.6 vs. 1.8 ± 0.7°C) gradients, compared to those of the supine position. Similar differences were observed during AS. Conclusion:, Perfusion index is a good non-invasive estimate of tissue perfusion. Prone sleeping position is associated with a higher PI, possibly reflecting thermoregulatory adjustments in cardiovascular control. The effects of these position-related changes may have important implications for the increased risk for sudden infant death syndrome in prone position. [source] | ||||||||||