Search results for "RTB"
showing 10 items of 58 documents
Silver Nanoparticles Affect Functional Bioenergetic Traits in the Invasive Red Sea Mussel Brachidontes pharaonis
2016
We investigated the functional trait responses to 5 nm metallic silver nanoparticle (AgNPs) exposure in the Lessepsian-entry bivalveB. pharaonis. Respiration rate (oxygen consumption), heartbeat rate, and absorption efficiency were evaluated across an 8-day exposure period in mesocosmal conditions. Basal reference values from not-exposed specimens were statistically compared with those obtained from animals treated with three sublethal nanoparticle concentrations (2 μg L−1, 20 μg L−1, and 40 μg L−1). Our data showed statistically significant effects on the average respiration rate ofB. pharaonis. Moreover, complex nonlinear dynamics were observed as a function of the concentration level and…
Psychometric validation of the Italian translation of the gastrointestinal symptom-rating scale and quality of life in reflux and dyspepsia questionn…
2007
Background: Symptoms of heartburn and their impact on health-related quality of life (HR-QOL) are often evaluated in clinical trials. When a questionnaire is translated into a new language, a linguistic validation is necessary but not sufficient unless the psychometric characteristics have been verified. Objective: To document the psychometric characteristics of the Italian translation of the Gastrointestinal Symptom-Rating Scale (GSRS) and Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire. Patients and methods: 152 consecutive patients with symptoms of heartburn (mean ±SD age 46.5 ± 16.2 years; 40.1% males) completed the Italian translation of GSRS, the heartburn version of QO…
Contingent biofeedback outperforms other methods to enhance the accuracy of cardiac interoception: A comparison of short interventions.
2019
Abstract Background and objectives Deviations in interoception might contribute to the development and maintenance of mental disorders. The improvement of interoceptive accuracy (IA) is desirable but assessment and training methods remain controversial. For instance, it was assumed that performance increases in heartbeat counting paradigms after cardiac feedback were due to an improvement of knowledge with regard to heart rate rather than due to an actual improvement in IA. Methods Here, we examined effects of contingent cardiac feedback training, non-contingent cardiac feedback, mindfulness practice, and a waiting period with external attentional focus on IA. 100 healthy participants under…
Optical noninvasive monitoring of skin blood pulsations
2005
Time-resolved detection and analysis of skin backscattered optical signals (remission photoplethysmography or PPG) provide rich information on skin blood volume pulsations and can serve for reliable cardiovascular assessment. Single- and multiple-channel PPG concepts are discussed. Simultaneous data flow from several locations on the human body allows us to study heartbeat pulse-wave propagation in real time and to evaluate vascular resistance. Portable single-, dual-, and four-channel PPG monitoring devices with special software have been designed for real-time data acquisition and processing. The prototype devices have been clinically studied, and their potential for monitoring heart arrh…
Making sense of what you sense: Disentangling interoceptive awareness, sensibility and accuracy.
2016
Garfinkel and Critchley (2013) recently proposed a three level model of interoception. Only few studies, however, have empirically tested this theoretical model thus far. The present study aimed at investigating (1) the central assumptions of this model, i.e. that Accuracy, Sensibility and Awareness are distinguishable facets of interoception and that Interoceptive Accuracy is the basic level of interoception, and (2) whether cardiovascular activation (as indexed by heart rate) is differentially related to the three facets of interoception. Analyses were conducted on a total sample of N=159 healthy participants (118 female [74.2%]; mean age=23.9years, SD=3.3, range=19-45) who performed eith…
A new heart rate variability-based method for the estimation of oxygen consumption without individual laboratory calibration: Application example on …
2008
Traditionally, the estimation of oxygen consumption (VO2) at work using heart rate (HR) has required the determination of individual HR/VO2 calibration curves in a separate exercise test in a laboratory (VO2-TRAD). Recently, a new neural network-, and heart rate variability-based method has been developed (Firstbeat PRO heartbeat analysis software) for the estimation of VO2 without individual calibration (VO2-HRV). In the present study, the VO2-values by the VO2-HRV were compared with the values by VO2-TRAD in 22 postal workers. Within individuals the correlation between the two methods was high (range 0.80-0.99). The VO2-TRAD gave higher values of VO2 compared to VO2-HRV (19%) especially d…
Improving heartbeat perception in patients with medically unexplained symptoms reduces symptom distress.
2013
Abstract Distortions in interoceptive accuracy have been linked to somatoform disorders. In line with cognitive theories of symptom formation in somatoform disorders, decreases in interoceptive accuracy have recently been observed to co-occur with more severe symptom reports. The current study tested the hypothesis that experimentally increasing interoceptive accuracy should decrease symptom severity in somatoform disorders. Twenty-nine patients with somatoform disorders were instructed in a newly developed heartbeat perception training procedure. Heartbeat perception, as a proxy for interoceptive accuracy, was assessed with a mental tracking task. Although there were no significant differe…
Health anxiety – An indicator of higher interoceptive sensitivity?
2013
Abstract Background and objectives According to cognitive-behavioral models, health anxiety arises from the misattribution of normal bodily sensations as signs of a severe illness. Consequently, higher levels of interoceptive accuracy might be critically involved in the development of health anxiety. Methods To test this central assumption of cognitive behavioral models of health anxiety, we assessed interoceptive accuracy in a sample of college students ( N = 100). Two interoceptive tasks (detection of one's own heartbeat using the Schandry paradigm and detection of nonspecific skin conductance fluctuations, NSCFs) were used. Results We found no indication for a positive association betwe…
Instantaneous Transfer Entropy for the Study of Cardiovascular and Cardio-Respiratory Nonstationary Dynamics
2017
Objective: Measures of transfer entropy (TE) quantify the direction and strength of coupling between two complex systems. Standard approaches assume stationarity of the observations, and therefore are unable to track time-varying changes in nonlinear information transfer with high temporal resolution. In this study, we aim to define and validate novel instantaneous measures of TE to provide an improved assessment of complex nonstationary cardiorespiratory interactions. Methods: We here propose a novel instantaneous point-process TE (ipTE) and validate its assessment as applied to cardiovascular and cardiorespiratory dynamics. In particular, heartbeat and respiratory dynamics are characteriz…
Esophageal abnormalities in morbidly obese adult patients.
2015
Abstract Background An increase in body mass index has been found to be associated with an increase in the prevalence of gastroesophageal reflux disease (GERD) symptoms, esophageal mucosal injury, and GERD complications. Few systematic studies with objective tests have evaluated esophageal disorders in the morbidly obese population. Objectives To define more precisely in morbidly obese people the incidence of esophageal symptoms and characterize the esophageal disorders using objective data. Setting University Hospital, Spain. Methods Two hundred twenty-four presurgical morbidly obese patients were submitted to a protocol including a clinical history and objective tests (endoscopy, stationa…