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[Dynamics of population genetics parameters and their statistical during assessment selection for quantitative characters. I. An additive model. One character].

The selection for a single additively inherited quantitative character is studied using computer models of 3 types: 1) all the individuals had the same viability, and the paratypic deviation does not depend on their genotype; 2) differential viability of genotypes is taken into account with respect to a number of heterozygous loci; 3) differential paratypic deviation is estimated, it is introduced like viability in the model 2. Two types of trancation selection, stabilizing and directed, under the selection coefficient of approximately 0.5 are studied. There are studied dynamics of genotypic (omega2gamma) and phenotypic (omega2phi) variances, the heritability index and it estimates (for the correlation progeny-parent--rho; for the regression progeny-parent--b; for half-sibses--v), and the non-equilibrium of a population for the models. The number of generation was 10; the population number in every generation was 200; the number of loci in the main experiment was 10.h2 values were calculated in the progeny before selection (p1, b1, v1) and after selection (p2, b2, v2). It is shown that stabilizing selection results in the formation of balanced gene complexes; the rate of decreasing omega2phi depends on the genetic length of a chromosome region in which genes, determining the character, are located, and not on the number of genes. The distribution of a character under directed selection depends on the type of the model. p2, b2, and v2 values are the worst. The best is the b1 value. It is concluded that the problem of predicting the selection effect using statistical estimates of heretability is connected with the problem of investigation of population heterogeneity and integrating their genetical structure.

Computers

Neurologic soft signs in schizophrenia and character disorders. Organicity in schizophrenia with premorbid asociality and emotionally unstable character disorders.

Previous studies indicated that for two subgroups of patients, schizophrenics with premorbid asociality (SPA) and individuals with emotionally unstable character disorders (EUCD), central nervous system damage may have etiologic significance. It was hypothesized that these two patient groups would also have an increased number of neurologic soft signs. The relationship of neurologic examination, tests of auditory-visual integration, and intelligence quotient, and diagnoses was studied for 350 patients. Tests of reliability and persistence for all observed signs were performed. The EUCD and SPA groups had increased evidence of neurologic soft signs. Differences in patterns of IQ scores also suggest that different forms of brain damage may be present in these two groups. When the two groups were removed from the larger patient sample, those patients with other types of schizophrenia and character disorder did not exhibit evidence of neurologic impairment. This study of neurologic soft signs adds to the validity of considering SPA and EUCD as separate diagnostic entities.

Central Nervous System Diseases

[Contribution towards the study of the average visual-evoked response; non-gaussian character of spontaneous electroencephalographic activity; non-independence of noise and signal; possible non-stationary character of evoked response (author's transl)].

The succession of amplitudes constituting spontaneous electroencephalographic activity cannot be regarded as a strictly normal distribution. Spontaneous activity and the evoked response are not independent. The signal (evoked response)is, in some cases, non-stationary. The average visual-evoked response comprises several successive temporal fragments of which the stationary character varies. This variability of the average visual-evoked response argues in favour of the complexity of its genesis.

Adult

The depressive character.

The depressive character is characterized by perpetual and unsuccessful efforts to maintain self-esteem and to avoid a sense of helplessness. Such individuals suffer from chronic depression which may or may not be masked, but which permeates their character. Although the condition is among the commonest seen in many of our clinics and practices, it remains without a generally accepted diagnostic form. It is suggested that the essential, clinical, dynamic, and structural features of the depressive character are: (1) consistently low self-esteem and a sense of helplessness, dependent object relations and chronic guilt; (2) self-directed aggression and masochism are frequent but not invariable; (3) extensive use of the mechanism of denial is as common as the previously described obsessional defenses seen in patients subject to psychotic depression; (4) often the depressive character suffers from intense oral envy; (5) depressive character traits may help to ward off any of the basic anxieties, namely, object loss, loss of love, castration anxiety, and superego anxiety (guilt) (6) the depressive character may be similar to a number of related disorders, namely, the obsessional character, hysterical characters with a large oral component, and depressive borderline states; (7) sensitivity to loss, sadness, and fragility of self-esteem makes the depressive character especially vulnerable to regression into overt depression; (8) the persistence of oral incorporative mechanisms, ambivalent, dependent object relations, ego versus superego tension with depressive affect, and sensitivity to loss are characteristic of the ego of the depressive character.

Adult

Familiarity of background characters in visual scanning.

It is much easier to look for an unfamiliar character (upsidedown A) embedded among familiar ones than to look for a familiar character (A) among unfamiliar ones. Furthermore, the nature of the background seems more important to performance than the nature of the target. The basic experiments involved showing subjects a matrix with nine characters. On target-present trials, eight of the characters were background items and one character was a target item. On target-absent trials, all nine matrix positions were filled by background characters. The types of unfamiliar characters used were rotated English letters, partial letters, and Gibson figures. The familiar characters were upright English letters or digits. Search was easier through familiar backgrounds than through unfamiliar backgrounds with all of the character types used and whether measuring speed or accuracy.

Attention

Quantitative characters of potential value in studying mutagenesis.

The use of polygenic characters in testing for mutagenicity appears promising. Characters chosen should be easily measured and highly heritable, with a reasonable proportion of the genetic variance being of the additive type, as this implies that polygenic mutations affecting the character would be detectable in the heterozygous state. Changes in such characters may arise as a result of pleiotropic effects of major gene mutations that affect early steps in metabolic pathways.--No single character is likely to be entirely satisfactory; rather a diverse group of biochemical, anatomical and physiological characters, including growth and behavior, should be studied. Mandible shape appears to be particularly promising. The characters may be analysed simultaneously using multivariate techniques. Special attention should be paid to the detection of outliers, which may then be investigated by more classical methods for the presence of mutants. Thus, easily measured, highly heritable polygenic characters may be useful in screening animals for the presence of mutations.

Animals

Building phenotypic character matrices for phylogenetic inference: exploration of 35 years of practice.

Recent methodological development in phylogenetic inference has focused predominantly on molecular data. However, renewed interest in other data types, particularly morphological data, has followed from the increased recognition of the power of total evidence and tip-dating approaches, including fossil data, for inference of time-scaled trees and rates of evolution. However, attention has largely focused on the improvement of models of morphological evolution and other analytical tools with much less discussion about data acquisition itself. Here we review past and current practice for describing and collecting morphological data for phylogenetic inference. We present a systematic review of 164 phylogenetic analyses conducted over the last 35 years and focused on a diverse group of extinct arthropods: trilobites. Trends in increasing matrix size, data type, and coding strategy are evident. Where present, polymorphic characters have been predominantly derived from discretized continuous characters, although increasingly practitioners are utilizing alternative approaches for the treatment of quantitative characters. Not surprisingly, traditional indices that describe character consistency are highly correlated with matrix size but show surprising variation at different taxonomic scales. More recent attempts to describe data quality using information theory imply that characters can have high information content even if data are missing for many tips, providing support against the exclusion of characters because of missing data. In consideration of this, as well as advances in the study of developmental biology and variational complexity, we identify several avenues for increasing the quality and quantity of morphological data going forward.

Phylogeny

Methods of utilization of regularities in modificational variability of quantitative characters in plant breeding.

The nature of the modificational and genotypic variability of 30 quantitative characters in wheat varieties with different numbers of genes for dwarfing, and nine characters in contrasting pea varieties, differing in leaf type, was investigated. The experimental data, obtained in 1971--1974 and analyzed in the M-220M and Minsk-22 computers, showed a high degree of similarity in the modificational variability of similar quantitative characters for all varieties of the same crop. Significant similarities were also found in the modificational variability of identical quantitative characters for the two species (wheat and peas), which showed that the regularities in modificational variability are generally applicable in biology. The coefficients of variation, calculated from the total data obtained, for modificational (CVm), genotypic (CVg) and overall modificational-genotypic (CVm+g) variability, for the different quantitative characters, may be useful criteria in plant breeding. They may reveal genotypic differences in the quantitative characters in hybrids and mutant populations, and may thus be useful in improving the efficiency of selection of wheat and pea strains.

Agriculture

The pedophilic offender with antisocial character.

The purpose of the study was to clarify how pedophilic offenders with antisocial character (psychopathy) differ from "ordinary" pedophilic offenders, among whom there are many persons with immaturity and contact difficulties. For this purpose all pedophilia cases subjected to mental examination during a period of 25 years were investigated. Of these 81 cases, 38 could be regarded as antisocial characters on the basis of the current diagnostic criteria. The others were regarded as controls. The criminals with antisocial character had also been involved in other kinds of crimes and had had hyperactivity problems more often than controls. The controls were often immature, had a low intelligence, and were less able to have relations with adult people than were antisocial characters. However, according to the present results, these features might also make criminals with antisocial character more susceptible to pedophilia.

Adult

[Variability and inheritance of behavior in fine-wool sheep. II. Character of inheritance of domesticated behavior and correlation of behavior with productivity traits in fine-wool sheep].

The results of an experimental study of the inheritance of individual behaviour in various types of crosses are presented; the phenotypic and genetic correlations between the behavior and producutivity characters in sheep and the possibility of applying behaviour characteristics to the selection process of fine-wool sheep are analysed. It is shown that the progeny from crosses between parents with the same type of behaviour inherits mainly the type of behaviour of their parents and that, in general, the inheritance has a polygenic character. A genetic relation between the type of domestic behaviour and the productive characters of fine-wool sheep is established. The genetic correlation coefficient between the behaviour and the wool productivity is 0,57, and that between the behaviour and the live weight is 0,53. It is concluded that the inheritance component contributes to the formation of the type of domestic behaviour of fine-wool sheep. Phenotypic and genetic correlations between the type of behaviour and the main productivity characters are discussed. The posibility of using behaviour characteristics as a character under selection is considered.

Animals

The psychotic character.

A warp in the childhood emotional pattern may involve the ego and superego enough to cause psychotic elements or coloring, which may evolve into the psychotic character or into the potential for it or for psychosis. A brief review of relevant literature and a series of clinical vignettes are presented from the perspective of Alexander's model of the neurotic character. The psychotic is seen as showing: the dynamics of the neuroses acted out as in the neurotic character; narcissistic egocentricity and a failure of emphathetic, sympathetic identification and loving object relations; id impulses rationalized by a distortion of reality (manifested not in specific delusions, but rather, more diffusely throughout the ego); minimal or no insight into illness, as in criminality; and a failure of defenses against id impulse although the ego organization is intact. The clinical material reveals that these elements are encountered in all combinations and gradations; several types of psychotic character are discussed.

Adult

Alienation: character neuroses and narcissistic disorders.

Various defensive adaptations are described that patients with structural defects involving the self-representation (character neurotics) use to adapt to the external world, often achieving an organization sufficiently stable to lead to considerable success. Externalization rather than projection is used. The differences between these two psychic processes are important for our understanding of character neurotics. Projection signifies placing impulses or parts of the self into external objects whereas externalization involves creating or finding a reality to support the defences, including projecting. The patient externalizes his infantile traumatic environment to construct a current world after his early environment which he finds both threatening and familar. Clinical material illustrates how the process of externalization operating within the transference context may lead to special technical problems. One type of character neurotic demonstrates a special type of externalization which supports overcompensatory feelings of self-aggrandizement, which are in effect, narcissistic defenses. To varying degrees, all character neurotics have some narcissistic defenses. Countertransference problems are also discussed.

Adaptation, Psychological

[Studies on the additive character of amino-acid absorption data obtained from pigs. 2. Studies using regression technic].

The first communication in this series (MEIER et al. 1973) reported the results of studies on the additive character of amino acid absorption data from pigs which were based on the use of the classics technique. In order to verify these results the studies were repeated, partly with the same components using regression techniques. The present studies on the additive character of amino acid absorption data showed that the additive character of these data can also be established in pigs. Moreover, the results of these investigations indicated that studies on the additive character of amino acid absorption values may be carried out by using the classical method. In performing studies of this kind attention should be paid to the fact that the rations tested should be such as to meet or nearly meet the maintenance needs of the animals.

Amino Acids

[Nutrition and taxonomy of "enterobacteriaceae" and related bacteria. III. Nutritional characters and differentiation of the taxonomic groups (author's transl)].

A batch of 186 strains belonging to the families Enterobacteriaceae or Vibrionaceae has been studied by determination, for each strain, of the "versatility" towards 146 organic substrates tested as sole source of carbon and energy. This study allowed to work out a classification of these strains into the 32 classes which have been previously described. In the present paper the nutritional characters of these classes are reported. On the basis of these characters, the 32 classes may be regrouped into 7 groups, namely: (1.1) "Escherichia-Salmonella-Citrobacter", (1.2) "dystrophic Klebsielleae", (1.3) "eutrophic Klebsielleae", (2.1) "Shigella", (2.2) "Proteus", (2.3) "Aeromonas-Vibrio", (2.4) "Edwardsiella tarda-Aeromonas salmonicida-Plesiomonas shigelloides". Only 4 strains (about 2 percent) happened misclassified in this study where the taxa were assembled exclusively by means of nutritional characters. The number and the type of the substrates which can be used in each group are reported, as well as the nutritional characters which are possibly useful to differential diagnosis. The taxonomic considerations which may be deduced from this study are discussed.

Amino Acids

Nonlinear dependence of biological activity on hydrophobic character: the bilinear model.

In homologous series of compounds biological activity is linearly dependent on hydrophobic character until a cut-off point is reached where this linear relationship changes to a nonlinear relationship: biological activity increases with increase of hydrophobic character, reaches a maximum and then decreases with further increase of hydrophobic character. Drug transport in biological systems is determined by the rate constants of transfer of the drug through aqueous and organic compartments. In simple in vitro systems the rate constant k1 of transport of a drug from an aqueous phase into an organic phase and the rate constant k2 of the reverse process can be described as functions of the partition coefficient P: log k1 = log P - log (beta P + 1) + c and log k2 = - log (beta P + 1) + c. Observed and calculated k1 and k2 values are used to simulate drug transport in different multicompartment systems. Based on the McFarland probability model a new model for the quantitative description of the dependence of biological activity on hydrophobic character, called bilinear model, log 1/C = a log P - b log (beta P + 1) + C, has been derived recently: unsymmetrical curves with linear ascending and descending sides and a parabolic part within the range of optimal lipophilicity result from this model. The bilinear model is applied to experimental data of drug absorption, drug distribution and drug activity in biological systems. A comparison of the parabolic model and the bilinear model shows that in nearly all cases a better fit of the data results from the bilinear model.

Acids