Determination of indium by adsorptive stripping voltammetry at the bismuth film electrode using combined electrode system facilitating medium exchange.

A novel method of determining indium has been described in this article which uses adsorptive stripping voltammetry (AdSV) and 4-(2-pyridylazo)-resorcinol (PAR) as a chelating agent or as the preconcentration agent. The measurements were performed using square-wave voltammetry by using a combined electrode system, which allows for preconcentration and stripping without opening the circuit. Ex situ plated bismuth film electrode (BiFE) was used as the working electrode.

Voltammetric studies of glutathione transfer across arrays of liquid-liquid microinterfaces for sensing applications.

The simple and facilitated transfer of tripeptide glutathione across the water/2-nitrophenyl octhyl ether interface was studied via cyclic voltammetry at interface between two immiscible electrolyte solutions (ITIES). The micro-perforated membrane prepared with a laser with a femtosecond pulse was used for mechanical stabilization of the interface. The method of cyclic voltammetry was used to study the passive and facilitated interfacial transfer of glutathione and its complex with the crown ether dibenzo-18-crown-6 (DB18C6).

Autonomous dysregulation of orthostatic disorders in young individuals engaged into manual work.

The authors analyzed changes of statistic, spectral and non-linear parameters of cardiac rhythm variability in response to active orthostasis test in young individuals engaged into manual work, and the results are compared with hemodynamic parameters. Evidence is that the patients with neurogenous fainting present sympathetic vasomotory regulation disorders even in young age; before clinical manifestation as orthostatic hypotension. In comparison with common tilt-test, spectral analysis of cardiac rhythm variability in active orthostatic test can be more useful to reveal early disorders of autonomous regulation.

Anesthesia management of a 20-month-old patient with giant unilateral wilms tumor.

Wilms tumour (WT) (or nephroblastoma) is one of the most common malignant kidney tumors in children. On subsequent stages clinically it is often characterized by abdominal hypertension syndrome, which, in turn, leads to development of respiratory insufficiency. Other symptoms comprise renal deficiency, hypertension, and abnormalities of hemostasis and hemogram.

[The characteristics of the clinical picture and treatment of patients with acute kidney failure in obstetrical pathology].

The examination of 45 patients with acute renal failure (ARF) caused by obstetric problems identified 3 types of its clinical course: 1) "pure" ARF; 2) ARF in the presence of sepsis, and 3) ARF in the presence of exogenous intoxication. Types 2 and 3 were more severe and showed higher mortality rates. The average number of hemodialysis sessions per patient was 2.

[Acute kidney failure in surgical patients].

The authors analyze their experience with the treatment of 150 patients with severe acute renal insufficiency. The causes of the acute renal insufficiency were surgical diseases, traumas, operative interventions. Hemodialysis was performed in all the 150 patients in the complex of curative measures.

[Mechanical and chemical patterns in the completion of isolated cell division].

Bicellular complex of a divided oocyte of the mollusc Lymnea stagnalis is chosen as a "testing machine" for studying mechanical and biochemical properties of the membranes of interblastomere wall. The membrane material is described by a standard rheological body. Rheological and kinetic problems are considered.

[Growth, elastic and inelastic deformations in morphogenetic processes].

On the basis of rheological equation of standard body (as a physical state equation) the stress relaxation or deformation delay (the creep) accompanying the growth of adjacent layers (the model) or the growth of acetabularia apex are studied. It is shown that both initial geometrical characteristics of elastic and viscoelastic deformations determine final morphogenetic complication of bioconstructions, while time characteristics of deformations--the viscosity parameters of growth. Additional morphogenetic switching of development occurs during abrupt (of the phase type) changes in materials states resulting, among other things, from metabolic catastrophs.

[Increase in the rigidity of bioconstruction material during the process of morphogenesis].

Structural rigidity of the material of cell wall in the cylindrical part of Acetabularia apex resulting from the fibrillar structure and of the cell wall properties and deformations realized during anisotropy, were studied. Values of Jung's moduli and Poisson's coefficient of the growing wall were obtained. It was shown that anisotropy of the material featured inner geometrical rigidity of the bioconstruction which restricted the deformations, and in case of structural instability predetermined their morphogenetic switching.

[Mechanical deformations of bioconstructions during different stages of morphogenesis].

The stress-deformation regularities of the body behaviour are taken as principal pattern formation factors in bioconstructions: mutually compressed cap rays of Acetabularia and contiguous tissue layers (the model). With the growth of rays or layers mechanical tensions which are initiated in them increase. If no morphogenetic loss of shape stability is resulted, an alternative algorithm of natural complication of their initial pattern is finally realized and ruptures, shifts and other deformations are formed in some weakened elements of the constructions.

[Deformation and morphogenesis of Acetabularia cell membrane. II. Local mechanisms of regulating viscoelastic deformations].

Relationships between growth velocities of some parts of Acetabularia cell, ratio between the thickness of the cell membrane and apex diameter (its constructive rigidity), intracellular pressure and viscose-elastic deformations are used for physical substantiation of Waddington's concepts concerned with the existence and important search of local morphogenetic mechanisms. Their realization in a strongly deformated regions of Acetabularia cell membrane is shown. The relationship between viscosity, synthesis of the material and dimensions of region and intracellular pressure is found.

[Deformation and morphogenesis of Acetabularia cell membrane. I. Relation of deformation to genetic and geometric factors].

Relationships between the changes of geometric shape, volume and deformations of the apical growth part of acetabularia cell are studied. Jung module E approximately 25 kg/cm2, viscosity coefficient of the apex cell theta 4 - 10(4) kg-sec/cm2 and intracellular pressure P approximately 1 kg/cm2 are measured. Cell shape formation according to Waddington is concerned with simple physical factors which are under the genetic control.

[Number of whorls and umbel rays in Acetabularia].

It was found in the proposed model of morphogenesis of Acetabularia that the number of whorls N (as well as the number of umbel rays) depends on the degree of mechanical instability of the deforming cell wall (the greater is instability, the higher is the value N). The genetic control of final morphogenetic processes can be realized by setting definite physical conditions and properties. The theoretical estimates of N carried out for different cases agree fairly well with the experimental data obtained.

[Morphogenetic loss of shape stability in biological constructions].

The stress-deformation regularities are taken as basic pattern formation factors in biological macrosystems. Mechanical stresses occuring in the growing biological objects give rise to large deformations involving the loss of shape stability with the morphogenetical complication (fold production). Both theory and experiment show that the smaller is construction rigidity of macrosystem (Acetabularia mediterranea and Drosophila melanogaster) the larger is the number of the embryonal folds.