Sex-diagnosis of isolated Os coxae by discriminant functions

After methodical preparatory work on the selection of the metric characters and their technical definition, 16 variables were measured on every right hip bone in our standard series (Weisbach series). The discriminant functions performed on our standard series proved to be very sharply discriminant. The methodical foundation gained from the Weisbach series was applied to a control series (Tyrol series), whose sex had not been determined. The application of the discriminant analyses enabled a complete and plausible sex diagnosis to be made.     

A multifunctional system for automating physiological experiments

The methodical problems of automatization of physiological investigations on the basis of modern computer complexes "micro-CAMAC-lab" are discussed. The considered conceptions are illustrated by example of CAMEX-program-system ensuring the measurement, storing, visual control, editing and analysis of physiological experimental data.     

The theory and practice of constructing calibration curves in biodozimetry

The methodical peculiarities of experimental construction of regression "dose-effect" relationships used for the dose reconstruction are discussed. The method of computer simulations is applied to study the efficiency of different statistical procedures for plotting regression curves as well as the dependence of errors in dose prediction on the volume of examined material and on the choice of doses for a calibration curve. The causes of essential variability of calibrations obtained by different teams of researchers are discussed. A number of methodical recommendations is given for statistical processing of cytogenetic data. The procedure of constructing calibration dose dependence of the frequency of dicentrics on the basis experiments with in vitro gamma-irradiation of lymphocytes from blood samples of 5 donors is considered in detail. The expressions for statistical errors occurring in the dose reconstruction made on the base of the frequency of aberrations were derived and checked by the computer experiment.     

Operational experience of disinfection service of Novosibirsk region with liquidation of the avian flu foci in Kupinsky, Zdvinsky and Dovolensky regions in August, 2005

Results of work of disinfection service using a complex of disinfecion's measures on a mode against virus infections are resulted. In view of absence now methodical normative documents on modes of disinfection in the centers of the bird's flu the recommendations on use of new disinfectants are made.     

Un problema aperto: la didattica delle scienze nel mondo attuale

Abstract

An open question: the didactics of Sciences in the modem world. Here are mentioned the difficulties of the modern world to state the problem of didactics as far as a particular science is concerned, above all the Science of Nature. The difficulties are arising from the model of school our society is aiming at nowadays, the model of school completely different from that one of the past, it comes out the necessity to point out in which way the purposes of particular sciences have a place in that question.

That's an open question: any solution excluding the party concerned, that is teachers, seem to be unreal.

Here is the final proposal: an experimental research from teachers, a research coming back constantly through the deductive reasoning over the facts, starting from some hypotheses of work, a research that must be finished with the experimental, the methodical and the exact proof of the reliability of the hypotheses put forward.

Then there are some suggestions concerning the way of choosing the hypotheses of work.     

Principles of the design of an automated system for the quantitative analysis of the action of environmental factors on the body of laboratory animals

Complicated ecological conditions, caused by wide and active application of artificial chemicals, makes it necessary to reveal their effect on human and animal organism and take measures for protecting health. The possibility to use advanced computing and information devices in combination with specialized methodical approaches allowed to elaborate and build a model of a system for revealing fine and multi-aspect influence of various factors on organisms of experimental animals. The results obtained allow to consider creation of similar systems a necessary and feasible task.     

A questionnaire technique for assessing the stress at work

Subjective perception of the stress at work is a phenomenon reflecting the experience-mediated relationship between the sum of objective conditions of work and the sum of individual's traits available to cope with demands of the work environment. This relationship is mirrored in the function of the whole organism and can be described using the formula S = f (E, D), where S = the state of the organism, E = exposure (i.e. the sum of all stressors the organism is exposed to), and D = disposition (i.e. the sum of traits the organism has available to cope with these stressors). Based on these theoretical considerations, a questionnaire has been developed as a tool for assessing the work stress in different groups of occupations. This "Work Stress Assessment" (WSA) questionnaire was used in a group of 4800 female employees from various branches of the printing industry. Of a total of 160 questionnaire items, 98 items were selected and used to assess the workload in these employees, using a 5-point rating scale of evaluation. The responses were processed statistically, separately for 3531 blue-collar and 1269 white-collar respondents. The use of the factor analysis method revealed that the two groups of jobs had 16 factors in common, 3 factors were specific for blue-collar and 2 factors for white-collar jobs. Judged by factor components, the responses of subjects were well structured and the perceived stress at work turned out to well reflect the reality of conditions of work, which confirms the construct validity of this methodical approach based on the subjective perception of occupational stress. High coefficients of consistency (0.959 for blue-collar and 0.946 for white-collar occupations) point to the reliability of this questionnaire technique. Thus, the WSA questionnaire appears to suitably complement the other methodical approaches aimed at assessing the stress at work in different groups of occupations.     

Hoigne reaction and its modifications]

The author analyzes 114 works published lately dealing with methodical improvement of Hoigne's reaction and its application both in experimental studies and in clinical practice. The great majority of the works (over 90) were referred to the use of modification of this reaction suggested by Klemparskaya and Raeva for detection of autoantibodies to the lysate of autoerythrocytes and organ extracts. This reaction was found to be useful for studying the autosensitization process in man and animals; its prognostic significance at the clinic was of importance since its intensity corresponded to the severity of the process and promptly decreased with effective treatment.     

Das Autoselect-System – ein Automatensystem zur Selektion von Antibiotikaproduzenten. I. Methodische Grundlagen und Umfang des Systems

The methodical principle of an automated selection system for antibiotic producers, the Autoselectsystem, consisting of six machines and a computer is explained. In order to work with this machines the following material is needed: Cassettes with 64 microculture cups for cultivation of colonies on agar, cassettes with glass-tubes for dilution of samples, and test-plates with 64 holes for performing the agar diffusion test. The cups, the tubes and holes are arranged in a pattern of 8×8. In a serie of papers the machines will be described.     

A new methodical approach to the determination of the quantum yield of the photoelectric conversion of electronic excitations in reaction centers of purple bacteria

A new methodical approach has been developed, which enables one to determine with a high precision (approximately 1.5%) the quantum yield of energy conversion in reaction centers isolated from purple bacterium. This parameter for reaction centers from Rhodospirillum rubrum was estimated to be 93.5 +/- 1,5%. Our methodical approach makes it possible to calculate quantum yield values for complete photosystems of purple bacteria.     

Analysis of the inheritance patterns of 5'-truncated copies of the German cockroach R2 retroposons in individual crosses

The inheritance patterns of the 5'-truncated copies of R2 retroposons were analyzed in individual crosses of the German cockroach. The recombination level within the cluster of ribosomal RNA genes was determined. It was demonstrated that only the frequencies of individual variants of 5'-truncated retroposon copies are appropriate for population analysis rather than the patterns characterizing individual X chromosomes. The methodical approach used in the work is convenient for studying the genetic variation in ribosomal DNA multigene families.     

The 3-phase reaction of cells of an MDCK culture to long-term exposure to antiviral chemical preparations

A study was made of the effect of antiviral drugs remantadine and deitephorine on dynamics in the changes in structure-function parameters, mitotic activity, protein and nucleic acid synthesis in the Madin-Darby canine kidney cell culture. The application of methodical complex and regression analysis methods, the approximation of experimental data with analytical functions showed general regularity in the monolayer cell population response to the effect of drugs. In the response of cell populations three phases are distinguished: the first phase--transient inhibition; the second phase--relative compensation; the third phase--pathological cell destructive process.     

Analysis of the inheritance patterns of 5′-truncated copies of the German cockroach R2 retroposons in individual crosses

The inheritance patterns of the 5′-truncated copies of R2 retroposons were analyzed in individual crosses of the German cockroach. The recombination level within the cluster of ribosomal RNA genes was determined. It was demonstrated that only the frequencies of individual variants of 5′-truncated retroposon copies are appropriate for population analysis rather than the patterns characterizing individual X chromosomes. The methodical approach used in the work is convenient for studying the genetic variation in ribosomal DNA multigene families.     

Comparative multifactorial analysis of combined administration of injection and peroral forms of an antibiotic with a microbial immunomodulator in experimental anthrax

Comparative efficacy of the use of injection and oral dosage forms of rifampicin in the subtherapeutic doses in combination with peptidoglycan , an immunomodulator of microbial origin, was studied in respect to experimental anthracic infection with application of multifactorial analysis. It was shown that the antibiotic and immunomodulator had a pronounced synergistic effect. Polynomial statistic models were developed and nomograms or equal level curves defining the survival rate and average life-span (ALS) of the experimental animals within a wide range of the antibiotic and immunomodulator doses and the peptidoglycan dosing time were plotted. The combined use of the injection rifampicin in the subtherapeutic doses and the immunomodulator provided a significant increase in the survival rate and ALS, whereas the use of the oral antibiotic in combination with the immunomodulator increased only the ALS and not the survival rate. Multifactorial analysis proved to be an optimal methodical approach to comparative study of various antibiotic dosage forms used in combination with immunomodulators under experimental conditions.     

Quantitative receptor autoradiography in the human brain. Methodical aspects

Quantitative receptor autoradiography on sections of the human brain raises methodical problems of which some are relevant also for studies in animal tissue, but others are unique in studies of human brain tissue. Procedures for the following methodical aspects are discussed: image analysis for quantitation of the regional distribution of receptor densities, saturation analysis on autoradiographs, influence of age and post-mortem delay and quenching of beta-radiation in brain tissue. The solutions proposed to these problems make receptor autoradiography in the human brain to a reliable method for studies of chemical neuroanatomy.     

Uptake of (3H)-leucine into the total proteins of various Sommer's sectors of the rat hippocampus in vivo and in vitro

The incorporation of 4.3-3H-L-leucine into total proteins of different Sommer's sectors of the rat hippocampus was studied. The labelling of the acid-soluble supernatant purified through anion exchanger, the specific activity of the proteins and the relative specific activity of the proteins following intraventricular and intraperitoneal application of 3H leucine were determined in vivo and, on hippocampal slices, in vitro. It has been consistently demonstrated in all experimental models that leucine is incorporated into total proteins of the hippocampal structures to a varying degree, the highest label being observed in the region "CA3". The findings seem to reflect differences in the protein synthesis of the individual hippocampal sectors. However, this conclusion was possible only on the basis of resuls taken as a whole, since each experimental model was afflicted with different methodical drawbacks limiting the interpretation of the results obtained.     

Accurate determination of vegetational change in meadows by successive point quadrat analysis

The point quadrat method can be used for determination of vegetational change in meadows of great species diversity. An appropriate sampling technique is described comprehending an apparatus of high rigidity and a shelter to keep off wind and rain. Sample size related to sampling time expense affects the number of species recorded and methodical error which is empirically determined by repetitive sampling. A setup of fixed points leads to higher accuracy than random sampling. When methodical error is quantitatively known, significant vegetational change can be detected by sampling at successive times.For fluctuation studies of plant populations in meadows the point quadrat technique should be preferred to visual estimates of plant cover because of its higher accuracy.Abbreviations f= frequency - s= standard deviation - Sr= variation coefficient - DWLS= distance weighted least squares     

Genome structure in higher plants. Reassociation kinetics of DNA from Vicia faba and Vicia sativa

The work been concerned with a study of the kinetics of reassociation of total DNA and that of the fraction of unique sequences in plants from the Vicia family, i. e. Vicia faba and Vicia sativa. The size of the genome was determined by the kinetics of reassociation of the DNA of the fraction of unique sequences and the amount of DNA per nucleus was determined cytophotometrically. It has been shown that the size of the genome expressed in C(0)t units and the size expressed in gramms are not the same which testifies to the absence of true unique genes in the genome of the species studied. The analysis of the possible methodical errors was carried out. On the basis of the data obtained a suggestion was made of a model of chromosomes organization including 12 units of polynemization for Vicia faba and 4 units for Vicia sativa.