Analysis of the structure of cardiac rhythm during treatment of auricular fibrillation with digitalis

The structure of cardiac rhythm was studied with the help of specialized computers during digitalization in 60 patients with atrial fibrillation of different etiology. The reduction of the heart contractions rate under digitalization is accompanied by certain changes in the structure of cardiac rhythm: the arrhythmic pattern of the ventricular contractions increases with a predominant growth of the number of long R--R intervals, the transitions from short intervals to longer ones become sharper, and portions of a relatively stable ventricular rhythm appear. Three main types of dynamics of the rhythm structure were distinguished on the basis of the changes in the interval R--R histogram. The described changes in the structure of cardiac rhythm are not specific, but when Digitalis drugs are used alone they can be used as additional criteria for digitalization.     

Evidence for a central substructure in a Lumbricus terrestris hemoglobin obtained with STEM low-dose and digital processing techniques

Applications of scanning transmission electron microscope (STEM) low-dose and digital image processing techniques to the annelid extracellular hemoglobin of Lumbricus terrestris have shown the existence of a central substructure. The techniques involve low-dose STEM images of less than 2 e/A2 irradiation. Many such low-dose images were then aligned in their symmetry, N-fold averaged, and summed. The central substructure appears to be supported by spokes which are connected to a surrounding hexagonal bilayer of 12 subunits. In comparison to the summed image of Nephtys hombergii hemoglobin which is known to possess a central substructure, the morphology of both central mass and spokes were very similar. This finding of a central substructure is consistent with the report of a small angle X-ray scattering study (Pilz et al., 1980, Int. J. Biol. Macromol. 2, 279-283) which predicted the possible existence of substructure in the center of the molecule.     

The cardiovascular effects of diazepam and of diazepam and pancuronium during fentanyl and oxygen anaesthesia

A study of the physiological behaviour of the synthetic compound Orthonil (alpha-chloro-beta-(3-chloro-o-tolyl)-propionitrile revealed a strong auxin activity in higher plants. Otherwise, Orthonil appeared not to be a herbicide-auxin. It is metabolized intensively in plant tissues. Among the identified metabolites, two compounds were detected which also exert a high auxin activity. It is concluded that at least a part of the apparent auxin activity of Orthonil may be due to alpha-(3-chloro-o-tolyl) acetic acid, one metabolite of Orthonil. Although Orthonil strongly stimulates elongation growth, this growth is not accompanied by a stimulated ethylene evolution as is the case with other auxins. A possible metabolic pathway of Orthonil is discussed.     

Atherosclerotic (systolic) hypertension

Systolic hypertension was studied in 92 patients, aged 60 to 103 years, some of them being followed-up for periods up to 8 years. The examination included that of haemodynamics, functional state of the heart and gas composition of blood (by the dye dilution technique, polycardiography, teleradiography, Sechenov and van Slyke methods, the micro-Astrup technique). The previously reported concept of the author was proved, i.e. the immediate haemodynamic cause of arterial pressure elevation in this pathology consists in an increased cardiac output against the background of an increased total elastic resistance of the arterial system. The elevation of the cardiac output is due not only to the neuro-humoral disorders in the regulation of arterial pressure in old age, but also to the adaptational factors directed to the improvement of oxygen transport and consumption by the tissues when the premeability of the vascular-tissuemembranes is impaired.     

Cytochemical studies of metaphase chromosomes by flow cytometry

The cytochemical properties of metaphase chromosomes from Chinese hamster and human cells were studied by flow cytometry. This technique allows precise quantitation of the fluorescence properties of individual stained chromosome types. Chromosomes were stained with the following fluorescent DNA stains: Hoechst 33258, DAPI, chromomycin A3, ethidium bromide, and propidium iodide. The relative fluorescence of individual chromosome types varied depending on the stain used, demonstrating that individual chromosome types differ in chemical properties. Flow measurements were performed as a function of stain and chromosome concentration to characterize the number and distribution of stain binding sites. Flow analysis of double stained chromosomes show that bound stains interact by energy transfer with little or no binding competition. For most hamster chromosomes, there is a strong correlation between relative fluorescence and stain base preference suggesting that staining differences may be determined primarily by differences in average base composition. A few hamster chromosome types exhibit anomalous staining which suggests that some other property, such as repetitive DNA sequences, also may be an important determinant of chromosomal staining.     

Minimax mutual information approach for independent component analysis

Minimum output mutual information is regarded as a natural criterion for independent component analysis (ICA) and is used as the performance measure in many ICA algorithms. Two common approaches in information-theoretic ICA algorithms are minimum mutual information and maximum output entropy approaches. In the former approach, we substitute some form of probability density function (pdf) estimate into the mutual information expression, and in the latter we incorporate the source pdf assumption in the algorithm through the use of nonlinearities matched to the corresponding cumulative density functions (cdf). Alternative solutions to ICA use higher-order cumulant-based optimization criteria, which are related to either one of these approaches through truncated series approximations for densities. In this article, we propose a new ICA algorithm motivated by the maximum entropy principle (for estimating signal distributions). The optimality criterion is the minimum output mutual information, where the estimated pdfs are from the exponential family and are approximate solutions to a constrained entropy maximization problem. This approach yields an upper bound for the actual mutual information of the output signals - hence, the name minimax mutual information ICA algorithm. In addition, we demonstrate that for a specific selection of the constraint functions in the maximum entropy density estimation procedure, the algorithm relates strongly to ICA methods using higher-order cumulants.     

Cognitive ability predicts objectively measured counterproductive work behaviors.

Over the past 2 decades, increasing attention has been directed at the relationship between individual differences and counterproductive work behaviors (CWB). However, most of this research has focused on personality variables as potential predictors of CWB; surprisingly little research has investigated the link between counterproductivity and cognitive ability. This study presents the first focal investigation of the cognitive ability-CWB relationship. The authors measured organizational and interpersonal CWB using organizational records of formally recorded incidents (e.g., destruction of property, physical violence). In a predictive study, for a large sample of law enforcement job applicants, a standardized psychometric test of cognitive ability predicted CWB, whereas educational attainment did not. (PsycINFO Database Record (c) 2010 APA, all rights reserved)