Theoretical and Experimental Analysis of the Hot Torsion Process of the Hardly Deformable 5XXX Series Aluminium Alloy

This work presents the results of the numerical and physical modelling of the hot torsion of a hardly deformable 5XXX series aluminium alloy. Studies were conducted on constrained torsion with the use of the STD 812 torsion plastometer. The main purpose of the numerical tests was to determine the influence of the accuracy of the mathematical model describing the changes in the yield stress of the tested material on the distribution of strain parameters and on the stress intensity. According to the preliminary studies, in the case of numerical modelling of the torsion test, the accuracy of the applied mathematical model describing the changes in the rheological properties of the tested material and the correct definition of the initial and boundary conditions had a particularly significant impact on the correctness of the determination of the strain parameters and the intensity of stresses. As part of the experimental tests, physical modelling of the hot torsion test was conducted. The aim of this part of the work was to determine the influence of the applied strain parameters on the distribution and size of grain as well as the microhardness of the tested aluminium alloy. Metallographic analyses were performed using light microscopy and the electron backscatter diffraction method. Due to the large inhomogeneity of the deformation parameters and the stress intensity in the torsion test, such tests were necessary for the correct determination of the so-called representative area for metallographic analyses. These types of studies are particularly important in the case of the so-called complex deformation patterns. The paper also briefly presents the results of preliminary research and future directions in which it is planned to use complex deformation patterns for physical modelling of selected processes combining various materials.     

Isovolumic contraction time of right ventricle in d-transposition of great arteries.

The pre-ejection period of the right ventricle in d-transposition of the great arteries is known to be prolonged, compared with the same interval of the left ventricle of normal subjects. In the present study, the echocardiographic measurement of the components of the pre-ejection period of the right ventricle of 14 patients with d-transposition of the great arteries shows that the isometric contraction time of the right ventricle in d-transposition of the great arteries is similar to the same interval calculated on the left ventricle of 76 normal children of comparable age. On the other hand, the electromechanical delay was significantly greater for the right ventricle of d-transposition of the great arteries than for the left ventricle of the normal subjects. It is concluded that the prolonged pre-ejection period of the right ventricle in d-transposition of the great arteries is not the result of right ventricular dysfunction but solely of a longer electromechanical delay.     

Principles of cooperation between the specialties of internal medicine, pathology and clinical biochemistry

The optimal utilization of the knowledge and possibilities of pathological and clinical biochemistry presumes a close cooperation between it and the clinical specialties. The common working team of the GDR Society of Internal Medicine and the GDR Society for Clinical Chemistry and Laboratory Diagnostics makes theses of the central points of the cooperation in care, education, further education and postgraduate study and in research a subject for discussion. As essential tasks in the process of medical care are regarded the balance of the examination programme standing at the disposal, the establishment of diagnostic programmes, the establishment of organisational measures, the ascertainment of a use according to indication, the guarantee of the representance of examination material, the control of plausibility and the interpretation of test results. Since the realization of the tasks to a large extent depends on the cooperation of the specialities in education, further education and postgraduate study during the further education the clinician should become acquainted with the possibilities, the limits and the prerequisites for the performance of laboratory diagnostic investigations, the clinical biochemist with the problems of medical care and the value of the laboratory diagnosis in the total process of the treatment. In the field of research the result is a necessary cooperation in the clarification of patho-biochemical mechanisms, in the search for suitable laboratory diagnostic parameters for diagnostics and control of the course as well as in the statement of the validity of laboratory diagnostic parameters and parameter combinations taking into consideration the factors expenses, benefit and risk as well as further diagnostic possibilities.     

Cytodiagnosis of the synovial fluid]

In a survey in a general part the differential-diagnostic approach in the establishment of cytological findings of the arthrocentesis for the judgment of the normal and pathologically changed synovial fluid are described. Especially the differential-diagnostic possibilities by constellations of the findings from determination of the total number of leucocytes, the differential cell picture and the determination of the individual signs characteristic for a disease are demonstrated. A special part deals with the assessment of the cytologic findings of the arthrocentesis for the diagnosis, the local and general judgment of the activity and the judgment of the therapeutic success of medicamentous and operative measures in rheumatoid arthritis with the help of the cytology of the puncture of a joint.     

Necrosis-Q in the mapping ECG

In this study 57 test persons 15 healthy ones, 42 patients with myocardial infarction with disturbances of the wall excursion) were examined by means of the mapping ECG, the classical ECG and the echocardiography. Considering the healthy test persons the normal values of the Q-deflections were established for every individual lead of the mapping ECG and of this the borderline values for the necrosis-Q (Q less than Q(m-1 s] were derived. The topographic coordination was performed with the help of a computer-aided picture of the thoracic surface. The determination of the localization of an echocardiographically proved disturbance of the wall excursion by means of the mapping ECG on the basis of the borderline values stated for the Q-deflections was carried out with an efficiency of 0.810 and by means of the classical ECG with an efficiency of 0.690. The information of the Q-deflections in the mapping ECG about the presence of an echocardiographically provable disturbance of the wall excursion is possible with an efficiency of 0.833. For the diagnosis of an infarction all infarction-typical parameters should always be used simultaneously. The clinical significance of the diagnostics of myocardial infarction by means of the mapping ECG lies in the exact localisation, the gradual valuation of the size of the infarction, in the recognition of changed potential distribution pattern as sign of the activity of a coronary heart disease with the complication of a myocardial infarction and the establishment of smaller as well as nontransmural myocardial infarctions with non-invasive methods.     

The value of laparoscopy within the framework of standardization of the diagnosis of stomach neoplasms]

Today the operative treatment of the carcinoma of the stomach is methodically mature. The prognosis is determined from the moment of the extension of the tumour. The establishment of the operability and of the tactical operative approach presumes an exact preoperative determination of the stage of the tumour using all possible diagnostic methods. While X-ray examination of the stomach and gastroscopy seize only the extension of the area of the tumour, the laparoscopy gives the possibility of an evidence of the deep growth of the tumour and metastasizing of the tumour and saves a test laparotomy for inoperable patients. A continuous interdisciplinary cooperation renders possible an immediate admission of the patient to a surgical clinic.     

The neuronal reaction of the amygdaloid complex in the dynamics of the estrous cycle

For investigation of the structural and functional organization of the amygdaloid complex (the cerebral neuroendocrine center) a response of its neurons to the fluctuations of circulating hormones was studied in the time course of the estrous cycle. Karyometry of 22 zones of the corticomedial group and 25 zones of the basolateral groups of the structure of the amygdaloid complex was performed in adult Wistar rats. A response of neurons of several zones of the corticomedial group of nuclei was revealed. A response of neurons of the basolateral nucleus at the caudal level of the central region was revealed in the basolateral group of structures of the amygdaloid complex.     

Compartmentalization of two forms of acetyl-CoA carboxylase in plants and the origin of their tolerance toward herbicides.

Acetyl-CoA carboxylase (ACCase, EC 6.4.1.2) catalyzes the synthesis of malonyl-CoA, the first intermediate in fatty acid synthesis. We studied the localization of two forms, the prokaryote and the eukaryote forms, of ACCase in pea leaves by comparing the biotin polypeptides of the two ACCases in protein extract from leaves and plastids. We found that the two forms of ACCase were in different cell compartments of pea leaves; the prokaryote form was in the plastids, and the eukaryote form was elsewhere, probably in the cytosol. This result suggested the existence of two sites of malonyl-CoA synthesis. The Gramineae, such as rice and wheat, which lack the accD gene encoding one of the subunits of the prokaryote form of ACCase in their chloroplast genomes, did not have the prokaryote form of the enzyme but had the eukaryote form. The selective grass herbicides of the diphenoxypropionic acid type and the cyclohexanedione type, in vitro, inhibited plastidic ACCase of the eukaryote form from wheat but did not inhibit that of the prokaryote form from pea, suggesting that the origin of the tolerance of intact pea plant toward these herbicides is partly in the insensitivity of the prokaryote form of the enzyme. The origin of the susceptibility of the Gramineae plants toward these herbicides seems to lie in the presence of the herbicide-sensitive eukaryote form and the absence of the insensitive prokaryote form due to the lack of the accD gene in plastid.     

Numerical Investigation of the Influence of Aerodynamic Loads on the Resonant Frequency of a Compressor Blade Made of EI-961 Alloy

The aim of this work was to numerically determine the influence of aerodynamic loads on the value of the resonant frequency of the compressor blade. The object of the research was the 1st stage compressor blade of the PZL-10W engine. As part of the research, analytical calculations of the resonance frequency were performed and compared with the literature ones (first, second, and third forms of forced vibrations). In the next step of the investigation, a computational model of the compressor stage (fluid domain and rotors) was built and FSI analysis was performed. This analysis was based on CFD modeling of the state of aerodynamic loads on the blade surfaces, and then these values were imported as external loads for the structural analysis, which was the basis for the modal analysis, in which the resonant frequency of the first three vibration modes was determined. As part of the analyzes, both the influence of aerodynamic loads and the rotational speed of the compressor rotor were verified. Thus, it was possible to evaluate the influence of both the rotational speed (and the arising centrifugal force) and the influence of the emerging aerodynamic load. The results obtained will allow for the assessment of the impact of the aforementioned operating conditions of the aircraft engine on the resonance frequency, which in turn may translate into the durability of critical components of the aircraft engine.     

Effect of thyrotoxicosis on adrenergic receptors, cyclic adenosine monophosphate, glycogen and enzymes of the myocardium

In the heart the interaction of the thyroid hormones, the catecholamines and the effect of the beta-blocker was studied. The binding of the radioactive noradrenalin (3H-NA) was higher in the particles of the thyreotoxic myocardium of the dog got by centrifugation at 1,000 and 78,000 g. The 3H-NA-binding was inhibited with propranolol, isoprenalin and in lower concentrations with trimepranol in dogs and also in rats. In the myocardium of the thyreotoxic dogs 3H-NA was less superseded with isoprenalin, in the myocardium of thyreotoxic rats less with non-active norarenalin in comparison to euthyroid animals. The thyreotoxicosis caused an increase of the activities of phosphorylase, of the lipases, of the calcium-dependent ATPase, the protein kinase in presence of histone, further a decrease of the activity of adenyl cyclase, particularly in presence of sodium fluoride and a decrease of the concentration of the cyclic adenosine monophosphate in the myocardium of the rats and dogs, respectively. The pharmacological thyreotoxicosis decreased the concentration of the heart glycogen. This decrease was inhibited by the beta-blocker trimepranol, but not by the alpha-blocker phentolamine. Three possibilities of the explanation of the findings of this complex study are cited. The influence of the thyroid hormones and beta-blockers 1. on the transport and calcium metabolism, 2. on the synthesis of the heart proteins, 3. on the backbinding control of the hormonal effect at cellular level.     

Institutional and personnel obstacles to the realisation of co-determination by old-age home inhabitants (author's transl)]

Following the intentions of the "Heimgesetz" partizipation of the residents does not only concern a better protection of their interests, but also a change in the traditional, hierachical structure of organization of the homes for the aged. A realization of this aim is not only faced by the position of power of the management. On the one hand the law itself restricts the nature and the range of the partizipation of the residents concerning decisionmaking in the institution. On the other hand the residents' committee got too little power to carry through the interests of the residents against the interests of the institution. So a considerable change in the traditional structure of the organisation is not very likely.     

Metabolism of free fatty acids in the intravascular space

With regard to the clinically relevant pathogenetic significance of hyperlipacidaemias a survey of the metabolism of the free fatty acids in the intravascular space is given. The transport of the free fatty acids by albumin and lipoproteins is demonstrated and the importance of the non-protein-bound fraction of the free fatty acids is emphasized. The dynamics of the metabolism of the free fatty acids is characterized with the help of the fractional and absolute turnover rate. Furthermore, the author deals with the participation of individual organs in the total metabolism and the metabolic fate of the free fatty acids as well as with the sources of this lipid fraction. Finally the regulation of the plasma concentration of the free fatty acids and its significance for the maintenance of the caloric homoeostasis is described.     

The effect of iodized mineral substance mixtures for cattle and swine on iodine requirements and struma prevention

In the southern districts of the GDR the calculated iodine uptake of adults was 80 micrograms/day before the iodine supplementation of the mixtures of mineral substances and the packet kitchen salt. The iodine supplementation of the mixtures of mineral substances for cattle and pig tripled the iodine content of the milk or increased it fivefold in the county of Erfurt and doubled the proportion of iodine of the meat, the inner parts and the sausage produced from them. In a daily consumption of 0.31 of milk and 250 g of meat and sausage a surplus supply of 35 micrograms of iodine for adults was calculated in the southern counties of the GDR. The 35 micrograms of iodine for the future necessary for covering the demand of iodine are certainly delivered by the iodized kitchen salt.     

Use of tritium oxide for the study of metabolism during development of experimental arteriosclerosis]

Theoretical grounds are presented for some methods (administration of isotope and time of sacrifying the animal, estimation of radioactivity in ther material examined, and mathematical processing of the data obtained) with which radioactive water is used as a universal precursor for the study of the integral rates of metabolism in various organs and biochemical components of the body. An analysis of the dynamics of tritium inclusion into the water of the blood and urine of the control animals and of those with experimentally induced atherosclerosis permitted to establish that the development of hypercholesterinemia is accompanied by a decrase (by 26%) of the rate of autorenuewal of the water phase of the macroorganism, one of its causes consisting in an enhanced hydrophility of the tissues in cases of this pathology. A monthly periodicity was noted in the changes of the tritium concentration in the body waters of rabbits, as well as its correlation with the periodical changes in the concentration of serum cholesterol during the development of experimental atherosclerosis. It is suggested that the water and cholesterol metabolism have a joint centralized regulation in the body which essence consists in maintaining the rhythm of each separate kind of metabolism for its synchronization with the other kinds of metabolism in unfavourable outer and inner situations for the macroorganism.     

Principles of differential pathogenesis-oriented therapy of various forms of osteopenia

From the demonstration of etiopathogenetic mechanisms of osteopenia 7 different histologically and histomorphometrically defined pictures of the state (diseases) of the skeleton are derived. From this 4 different possibilities of the influence on the permanent transformation of the skeleton--the remodeling are the result. The medicamentous support of the blockade or stimulation of osteoclasts and the optimization of the mineralization are the basis of therapeutic considerations. In the light of these pathogenetically orientated treatment strategies the real and at present practicable therapy regimes of the various clinical manifestations of the osteopenia and new beginnings especially also of the therapy of osteoporosis are discussed.     

蚤类的虫态变化

在平皿中潮湿滤纸上培育蚤卵、三龄老熟幼虫和无茧裸蛹,镜下连续观察卵的孵化、幼虫化蛹和蛹的羽化等动态过程,并通过显微录像法记录了上述虫态变化的详细过程。虫体自后向前一系列迭进式收缩所引起的压力增高是实现各期蜕变的基本动因。孵化开始于幼虫头部破卵器孵化刺将卵壳的割开,幼虫先后以胸—头—腹的顺序孵出,在2至数分钟内完成。化蛹时蛹体胸部首先从幼虫胸节背板中缝裂口处膨出,随之幼虫后头背中骨缝及一侧菱形骨缝裂开,蛹头、足和腹部相继蜕出,幼虫旧表皮腹节各背板均不裂开,化蛹过程多在10～20分钟内完成。羽化则以头—胸—腔的次序进行,一般需经5～20分钟。蛹衣从头顶横向裂开并脱下一个盔形物是羽化开始的标志。 观察了4属5种蚤41枚卵的孵化、8属10种蚤56条幼虫的化蛹和5属6种蚤25个蛹的羽化过程。结果表明,在以上虫态变化中,各种蚤的变化程序及虫体行为基本一致。对观察到的有关生物学和生态学现象进行了讨论。     

Metabolic syndrome in transplant patients: an updating point of view

Metabolic syndrome (MS) is a cluster of risk factors that predispose to major cardiovascular diseases and its complications, determining liver and kidney impairment. In the last decade, the indications to transplantation are increasing, with a linear incidence of the complications of the procedure. MS represents one of the commonest, being in turn may the consequence of the underlying disease that required the transplantation, or the result of the medical treatment, as well as one of the most important factor influencing the morbidity and mortality of the transplanted patients. Due to the growing incidence of the MS in these patients, it is crucial to focus and clarify the leading causes determining the onset of the metabolic disarrangement, its outcome and the hypothetical mechanism through which the clinicians could reduce the impact of the disease. In fact, prevention, early recognition, and treatment of the factor that could predict the onset or progression of the MS after the transplantation may impact long term survival of patients, that is again the scope of the same transplant. This review will update the different mechanisMS of the pathogenesis of MS in this population, the clinical effects of the presence of the MS, observing the risk factors to be treated before and after the transplantation and suggesting the management of the follow-up.     

Certain properties of estrogen receptors in the cell nuclei of different organs of rats]

Some properties of the macromolecules, specifically binding estradiol (E2) of salt chromatin extracts of the nuclei of the kidneys, liver, prostate, testes and the uterus of rats were studied. Examination of competition of various unlabeled hormonal preparations with 3H-E2 for the binding sites demonstrated the E2-binding macromolecules of the nuclei of all the organs under study to have a high hormonal stereo-specificity. The E2-binding macromolecules of the nuclear extracts of the kidney, liver and the uterus were sensitive to the action of pronase. In sedimentation with ammonium sulfate of proteins from the 0.3 M NaCl extracts of the nuclei of the kidneys and liver, but not of the uterus, the supernatent fraction of the salt-treated extracts showed an additional (in comparison with control) specifically E2-binding macromolecule activity, sensitive to the action of pronase. An analogous effect of the appearance of additional binding activity could be obtained in heating of the nuclear extracts of the kidney and the liver at 60--100 degress C for 5 minutes.     

Structural mechanisms for the realization of the secretory activity of human endocrine organs in prenatal morphogenesis

A study was made of the secretory active cells and intraorganic blood channel of the hypophysis, thyroid, thymus, ovaries and testes and human embryos and fetuses of 4-5 week -9 mos intrauterine development. The development of the hematocellular barriers in the human endocrine organs during the period of intrauterine development was studied from the view-point of the expression of their secretory activity. The time course of the transmission of endocrine information in the endocrine glands during prenatal morphogenesis determined by the phases of the development of transport communications of the microcirculatory system was studied. The system of contact means of the transmission of the secretory material was the first to function in the endocrine glands in the prenatal period of morphogenesis. The structural-functional formation and development of the microcirculatory system was a morphological base for the expression of the long- and short-distant means of the transmission of the secretory material to target cells and organs.     

Beta-receptor blockader therapy in the acute stage of myocardial infarct pathophysiological basis

The causal connection between the coronary occlusion and the necrosis of the myocardium, as it is verified again and again, is not unequivocal. The favourable effects of the beta-receptorblockers in the acute phase of the infarction of the height of the ST-elevations, the later levels of the CPK and the prognosis of the patients plead for the essential causal importance of the catecholamines in the infarctional process. The catecholamines have an effect on the myocardium increasing the contraction and dissipating oxygen. Through activations of the metabolism in the vascular wall they lead to subintimal swellings and to lesions of the endothelium and increase the aggregation of the thrombocytes. With the decreasing pH, value the flexibility of erythrocytes lowers and thus the microcirculation. Via positive feed-backs the acidosis of the myocardium increases, which via activation of lysosomal enzymes leads to the necrosis of the myocardium. beta-receptorblockers reduced the myocardial contractility, the increased glycogenolysis and the increased activity of the respiratory chains. The lesion of the vascular wall, the aggregation of thrombocytes and the decrease of pH are inhibited, by means of which the spreading conditions of the necrosis deteriorate. By the early application of the beta-receptor blockers the patho-mechanisms lying still in the functional region can be inhibited, thus the danger of early disturbances of rhythm and of the early cardiogenic shock. With the deterioration of the conditions of necrotization the prognosis of the patients with infarction improves.