concentration ([Ca 2ϩ ]i) handling and vulnerability to arrhythmias in a species-dependent manner. The effects of uncouplers were investigated in perfused mouse hearts labeled with rhod-2/AM or 4-[-[2-(di-n-butylamino)-6-naphthyl]vinyl]pyridinium (di-4-ANEPPS) to map [Ca 2ϩ ]i transients (emission wavelength ϭ 585 Ϯ 20 nm) and action potentials (APs) (emission wavelength Ͼ 610 nm; excitation wavelength ϭ 530 Ϯ 20 nm). Confocal images showed that rhod-2 is primarily in the cytosol. DAM (15 mM) and cyto-D (5 M) increased AP durations (APD 75 ϭ 20.0 Ϯ 3 to 46.6 Ϯ 5 ms and 39.9 Ϯ 8 ms, respectively, n ϭ 4) and refractory periods (45.14 Ϯ 12.1 to 82.5 Ϯ 3.5 ms and 78 Ϯ 4.24 ms, respectively). Cyto-D reduced conduction velocity by 20% within 5 min and DAM by 10% gradually in 1 h (n ϭ 5 each). Uncouplers did not alter the direction and gradient of repolarization, which progressed from apex to base in 15 Ϯ 3 ms. Peak systolic [Ca 2ϩ ]i increased with cyto-D from 743 Ϯ 47 (n ϭ 8) to 944 Ϯ 17 nM (n ϭ 3, P ϭ 0.01) but decreased with DAM to 398 Ϯ 44 nM (n ϭ 3, P Ͻ 0.01). Diastolic [Ca 2ϩ ]i was higher with cyto-D (544 Ϯ 80 nM, n ϭ 3) and lower with DAM (224 Ϯ 31, n ϭ 3) compared with controls (257 Ϯ 30 nM, n ϭ 3). DAM prolonged [Ca 2ϩ ]i transients at 75% recovery (54.3 Ϯ 5 to 83.6 Ϯ 1.9 ms), whereas cyto-D had no effect (58.6 Ϯ 1.2 ms; n ϭ 3). Burst pacing routinely elicited long-lasting ventricular tachycardia but not fibrillation. Uncouplers flattened the slope of AP restitution kinetic curves and blocked ventricular tachycardia induced by burst pacing. optical action potentials; action potentials; intracellular calcium; restitution kinetics MOLECULARLY ENGINEERED MICE have been extensively used to genetically alter a specific component of a complex signaling process and to develop models of human diseases. Transgenic mice are used as models for various cardiac diseases and offer an effective strategy to elucidate the mechanisms underlying long QT-related arrhythmias, metabolic diseases, and the pathology of heart failure (29). A limitation of mouse models is the small size of the heart, making it difficult to study changes in contractility, electrophysiology, and vulnerability to arrhythmias in intact hearts. The challenge of measuring changes in cardiac phenotype has been partly overcome by applying optical technique to map electrical activity, but a major technical difficulty in the application of optical techniques to measure action potentials (APs) and intracellular Ca 2ϩ concentration ([Ca 2ϩ ] i ) transients has been the distortion of the signals by movement due to muscle contractions.Several approaches have been used to reduce movement artifacts: 1) perfusion in Ca 2ϩ -free Tyrode solution to abolish contractions, an approach applicable to amphibian hearts (38); 2) design perfusion chambers to mechanically stabilize the heart (18, 37); 3) perfusion with an inhibitor of L-type voltage- Chemical uncouplers can potentially provide a practical approach to block movement artifacts and have been used to...
Since its introduction in 2001, the Electronically Activated Recorder (EAR) method has become an established and broadly used tool for the naturalistic observation of daily social behavior in clinical, health, personality, and social science research. Previous treatments of the method have focused primarily on its measurement approach (relative to other ecological assessment methods), research design considerations (e.g., sampling schemes, privacy considerations), and the properties of its data (i.e. reliability, validity, added measurement value). However, the evolved procedures and practices around arguably one of the most critical parts of EAR research-the coding process that converts the sampled raw ambient sounds into quantitative behavioral data for statistical analysis-have so far been largely communicated informally between EAR researchers. This article documents the "best practices" for processing EAR data that have been tested and refined in our research over the years. Our aim is to provide practical information on important topics such as the development of a coding system, the training and supervision of EAR coders, EAR data preparation and database optimization, the troubleshooting of common coding challenges, and coding considerations specific to diverse populations.
The results indicate a link between androgyny and marital adjustment. The results also suggest the type of match between dyads.
Frequent associations have been found between family interaction and anorectic behaviour. Family theorists have viewed anorexia as a manifestation of a dysfunctional family system. We report three families of cases of anorexia (one male and two female) where the symptom was a reflection of family pathology and was being maintained by it. The cases emphasize the need to assess families of anorectics in detail and view them in the cultural context of eating.
This paper reports the findings of a preliminary inquiry which is part of a larger project on creativity among Indian scientists from a psychological perspective. The aim of the project is to explore the scientists' cognitive and emotional ap proaches to work, to understand their personality pattern and to examine the psychosocial influences which have shaped them. The preliminary inquiry in cluded a review of literature and an open-ended interview with 20 scientists who were asked about their definition of creativity, their understanding of creative processes and the personality characteristics of creative people. In addition, infor mation pertaining to the impact of Indian culture on creativity and child rearing practices and codes of interpersonal relationship in India was also elicited. Inter view findings were subjected to a qualitative analysis, critically examining the scientists' views against the available literature on Indian character.
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