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PubMed1976

Effect of perceptual motor training on gross-motor skill and self-concept of young children.

Preschool teachers from four different day care centers assessed four-and five-year-old children for deficits in gross-motor skill and self-concept. Forty subjects were randomly assigned to experimental and control groups. The experimental group participated in a 30 minute per day, 5 day per week perceptual-motor training program for 10 weeks, while the control group received no specialized intervention other than their regular classroom activities. Two posttests were administered: Cratty's Six-Category Gross-Motor Test and Goodenough's House, Tree, Person Projective Test. The experimental group performed better on the gross-motor test, but the results were not statistically significant. Analysis of the projective test supported the hypothesis that a perceptual-motor program may improve the self-concept of young children. Specialized intervention with perceptual-motor activities improved self-concept and these results were discussed in relation to recognizing the need for early screening and remediation of perceptual-motor dificits exhibited by preschool children.

Child Development↗
PubMedDate not supplied

The physician-patient relationship: three psychodynamic concepts that can be applied to primary care.

Psychodynamic concepts can be used to help understand and manage certain difficulties that arise within the physician-patient relationship. The concepts of transference, countertransference, and action (in the form of acting out and enactment) are discussed. A case description is included to show how these concepts apply to the day-to-day practice of primary care medicine. Arch Fam Med. 2000;9:1164-1168

Acting Out↗
PubMed1996

Anthropometric analysis of the female Latino nose. Revised aesthetic concepts and their surgical implications.

OBJECTIVE: To determine whether the present aesthetic concepts set forth for rhinoplasty in white patients can be applied to the ethnic variations seen in Latino women and, if not, to develop a reproducible means of analysis to serve as a guide for surgical correction. DESIGN: Cohort analytic study; criterion standard analysis of nasal aesthetics. PARTICIPANTS: Ninety-seven Latino women and 40 white women. INTERVENTIONS: Patients were separated according to geographic area of origin, either the Caribbean, Central America, or South America. Anthropometric measurements were obtained and nasal indexes were calculated. Results were compared with previously reported data for African Americans and whites. All patients underwent complete nasal photographic analysis. RESULTS: Caribbean subjects showed the greatest divergences from whites and resembled African-American anthropometric norms, whereas Central and South American subjects more closely resembled white norms. Two new aesthetic concepts were developed, the dorsal nasal breakpoint and the horizontal nasal axis, which have implications for aesthetic rhinoplasty. The breakpoint is a pivotal point along the nasal dorsum, structurally determined, which was found at different locations in all the groups studied. Caribbean subjects had breakpoints approximately halfway down the dorsum. Central and South Americans had breakpoints about two thirds of the way down the dorsum, and whites had breakpoints three fourths of the way down the dorsum. The horizontal rotation axis is present along a plane that connects the top of the ala with the tip. Rotation of the tip about this axis affects both the characteristics of the dorsal breakpoint and the final appearance of the nose. CONCLUSIONS: In general, Latino noses can be anthropometrically categorized as mesorrhine. When the geographically derived groups were examined individually, the Latino nose ranged from subplatyrrhine to paraleptorrhine. Surgical correction should be individualized, as each group requires correction of different nasal features. The dorsal breakpoint and the horizontal axis plane can act as nasal profile guides for surgical modifications that would achieve the current concept of the aesthetic nose.

Adult↗
PubMed1975

The spectrum concept of schizophrenia. Problems for diagnostic practice.

The spectrum concept of schizophrenia posits that a number of psychopathologic states, both psychotic and nonpsychotic, may share some genetic basis with schizophrenia, and may therefore constitute, together with schizophrenia itself, a genetic spectrum of schizophrenic disorders. While this is a valuable and promising research concept, its application to diagnostic practice could broaden the boundaries of schizophrenia to include patients with other conditions, thus rendering a larger population at risk for the untoward effects of the schizophrenia disgnosis itself. This may have already occurred in the Soviet Union, where a diagnostic system derived from a variant of the spectrum concept is used in routine diagnostic practice. The adoption of a spectrum-based diagnostic system should await further research on the boundaries of the spectrum, and more detailed descriptions of confirmed spectrum states.

Bipolar Disorder↗
PubMed1998

Effect of paternal alcohol consumption before conception on infant birth weight. ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood.

Previous studies of paternal drinking and fetal growth in both animals and human have produced conflicting results. We evaluated the association between paternal drinking before conception and infant birth weight in a cohort of 9,845 liveborn singleton infant born to couples who participated in the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC), ALSPAC is a population-based cohort study in which women and their partners completed several self-administered questionnaires over the course of pregnancy. Of participating male partners, 20% were reportedly daily drinkers before conception, and 8% were considered moderately heavy or very heavy drinkers. Because maternal drinking is highly correlated with paternal, the analyses were stratified by maternal drinking in early pregnancy. We also adjusted for confounders and known predictors of birth weight. For all three maternal drinking strata, all adjusted mean differences in birth weight across levels of paternal drinking were similar, and all had confidence intervals that included zero. These findings persisted even after adjustment for other covariates and after stratification by parental smoking, race, and education. The size of the ALSPAC cohort, the large number of heavy drinkers, and the availability of data from the fathers themselves support the conclusion that paternal drinking before conception is not an important predictor of infant birth weight in humans.

Adult↗
PubMed1996

Using multiple indicators to test the dimensionality of concepts in the health promotion model.

Data from 197 randomly selected male adults were analyzed in order to examine the dimensionality of two of the concepts in the Health Promotion Model-perceived control of health and definition of health. The model, tested with LISREL, examines the impact of age on exercise with the key concepts modeled as intervening variables. The addition of multiple indicators resulted in a model that failed to meet the data constraints, thereby calling into question the putative dimensionality of perceived control of health and definition of health. The proportionality constraints within multiple-indicator structural equation models seem to provide a more stringent test of whether several indicators measure the same concept than the test provided by the internal consistency constraints implicit in factor analysis.

Adult↗
PubMed2003

Effect(s) of assisted hatching on assisted conception (IVF & ICSI).

BACKGROUND: Failure of implantation and thus conception might result from inability of the blastocyst to escape from its zona pellucida. Artificial disruption of this coat has been proposed as a method of improving the success of assisted conception. OBJECTIVES: To determine whether assisted hatching of embryos facilitates live births, clinical pregnancy and implantation and whether it impacts on negative outcomes (such as miscarriage). SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (26 November 2002), the Cochrane Controlled Trials Register (Cochrane Library Issue 2, 2002), MEDLINE (1996 to February 2003), EMBASE (1980 to February 2003) and reference lists of articles. Authors were contacted for missing and/or unpublished data. SELECTION CRITERIA: Trials were identified and independently screened by two reviewers. Randomised controlled trials of AH (mechanical, chemical or laser disruption of the zona pellucida prior to embryo replacement) versus no AH that reported live birth, clinical pregnancy or implantation rates were included. DATA COLLECTION AND ANALYSIS: Qualitative assessments and data extraction were performed independently by two reviewers. Outcomes were extracted as rates and combined using random effects meta-analysis, sensitivity analysis, subgrouping and meta-regression where appropriate. MAIN RESULTS: Twenty-three randomised controlled trials (2572 women) were included. There was no significant difference in the odds of live births in the AH compared with control groups (6 RCTs; OR 1.21, 95% CI 0.82 to 1.78; 161 births from 523 women). Women undergoing assisted hatching were significantly more likely to achieve clinical pregnancy (722 clinical pregnancies in 2175 women, OR 1.63, 95% CI 1.27 to 2.09), however the studies were heterogeneous. Implantation data were difficult to analyse due to the practice of replacing multiple embryos in individual women. The trials provided insufficient data to investigate the impact of assisted hatching on several important outcomes, including monozygotic twinning, embryo damage, congenital and chromosomal abnormalities, and in vitro blastocyst development. REVIEWER'S CONCLUSIONS: There is insufficient evidence to determine any effect of AH on the 'take-home-baby rate' of assisted conception. There are also very few data regarding miscarriage rates and other adverse events. This prevents us from extrapolating the impact of AH on live births from our finding of improved odds of clinical pregnancy.

Embryo Implantation↗
PubMed1976

Two concepts of adaptation: Darwin's and psychology's.

The paper takes issue with the traditional view of Darwin's influence on psychology; namely, that it is he who passed on to psychology the concept of individual adaptation. Three arguments are presented: a) that Darwin, qua scientist, was only interested in species adaptation, an entirely different concept from that of individual adaptation, b) that Darwin's writings on individual adaptation are so unexceptional that it is inconceivable that psychologists should have been influenced by them and c) that the two concepts are logically incompatible since species adaptation presupposes a strict hereditary determinism, while individual adaptation conceives of the organism either as free and undetermined or else as determined by the environment.

Adaptation, Biological↗
PubMed1990

Human genome analysis and the concept of human nature.

The possibilities opened up by human genome analysis appear to provide support for quasi-deterministic views of human nature but an analysis of the debate over sociobiology shows that we cannot derive a theory of human nature directly from biological and genetic evidence. From this perspective human genome analysis and the forms of human genetic engineering that it makes possible cannot alter our concept of human nature although they make us more aware of the 'plasticity' of the human. The possibility envisaged by some neo-eugenicists (and often accepted by their opponents) of a radical reshaping of human nature is as misconceived as the view of some sociobiologists that human nature is biologically determined. Human genome analysis raises formidable ethical, social and legal problems and we need to develop criteria that will enable us to decide which kinds of genetic manipulation will help to enhance human life and which will not. This will involve having a clear concept of human nature and the values it implies. But we shall not derive this concept of human nature from genetics itself.

Genetics, Medical↗
PubMed1991

Applications of the concept of attributable fraction in medical genetics.

Attributable fraction, the fraction of cases of a disease in a population attributed to a particular risk factor, is a useful measure in the design and interpretation of epidemiologic studies of disease etiology. We review here the applications of the concept of attributable fraction in medical genetics. Specifically, attributable fraction can be used 1) in studies of the association between genetic traits and specific diseases to quantitate the contribution of specific alleles to disease occurrence in a population; 2) in population studies of mutations and birth defects to estimate the impact of mutagens and teratogens; and 3) in genetic analyses of family data, to evaluate the contribution of putative single gene loci to disease etiology. In the latter context, the concept of attributable fraction can be contrasted with the more commonly used concept of heritability. Examples from the literature provide illustrations of the usefulness of attributable fraction in medical genetic studies.

Alleles↗
PubMed2005

Variation in the resumption of cycling and conception by fecal androgen and estradiol levels in female Northern Muriquis (Brachyteles hypoxanthus).

We measured fecal androgen (T+DHT) and estradiol (E2) levels in female northern muriquis (Brachyteles hypoxanthus) at the Estação Biológica de Caratinga/RPPN Feliciano Miguel Abdala, Minas Gerais, Brazil, to evaluate the hormonal bases underlying individual variation in the resumption of cycling and conception. We found that androgen levels were significantly lower in females than in males, and that there were no consistent patterns in female androgen levels across precycling or cycling conditions. Females that resumed cycling earlier in the study (weeks 4-8) had higher precycling E2 levels and correspondingly lower precycling androgen/E2 ratios than females that resumed cycling later (weeks 12-16). There were no differences in female precycling androgen levels, but cycling females that conceived during or immediately after the study period had lower androgen levels and threefold higher E2 peaks than the one cycling female that failed to conceive. These results suggest that minimum E2 thresholds are necessary for both the resumption of ovarian cycling and conception. Individual variation in these components of fertility may be regulated by differences in E2 levels, which affect androgen/E2 ratios, rather than by androgen levels per se. Further research into the relative concentrations of T vs. DHT will be necessary to fully evaluate whether androgens affect cycling and conception in this species.

Animals↗
PubMed1994

A critique of homology as a morphological concept.

Two sequences of nucleotides are homologous if they are descended through a chain of replication from a common precursor molecule. Since organs are not copies or transcriptions of organs, the concept of morphological homology has no such simple and unambiguous definition. The theoretical vagueness of morphological homology is reflected in its many and inconsistent criteria of identification. Structures may be conventionally deemed homologous even though they are radically dissimilar in form, relationships, or function, or develop via dissimilar ontogenetic processes, or originate from nonhomologous embryological precursors. Hypothesis of homology are conventionally rejected when they are contradicted by known patterns of phylogenetic relationships, even if the structures in question are minutely similar in their form, function, and development. The dependence of interspecific homology on phylogeny is often expressed by saying that two structures are homologous if they are inherited from corresponding structures in a common ancestor. However, this is a circular definition (what counts as a "corresponding" structure is itself a question of homology), and it falsely assumes that structures can be inherited. At bottom, homology is an essentialist concept; two things are homologous only if they are in some essential sense the "same" thing and properly called by the same word. The concept can be made intelligible in an evolutionary context only by giving it a cladistic interpretation that makes homology judgments dependent on the outcome of a phylogenetic analysis. It follows that such judgments cannot play a role in evaluating conflicting phylogenetic hypotheses.

Animals↗
PubMed2003

Species as family resemblance concepts: the (dis-)solution of the species problem?

The so-called "species problem" has plagued evolutionary biology since before Darwin's publication of the aptly titled Origin of Species. Many biologists think the problem is just a matter of semantics; others complain that it will not be solved until we have more empirical data. Yet, we don't seem to be able to escape discussing it and teaching seminars about it. In this paper, I briefly examine the main themes of the biological and philosophical literatures on the species problem, focusing on identifying common threads as well as relevant differences. I then argue two fundamental points. First, the species problem is not primarily an empirical one, but it is rather fraught with philosophical questions that require-but cannot be settled by-empirical evidence. Second, the (dis-)solution lies in explicitly adopting Wittgenstein's idea of "family resemblance" or cluster concepts, and to consider species as an example of such concepts. This solution has several attractive features, including bringing together apparently diverging themes of discussion among biologists and philosophers. The current proposal is conceptually independent (though not incompatible) with the pluralist approach to the species problem advocated by Mishler, Donoghue, Kitcher and Dupré, which implies that distinct aspects of the species question need to be emphasized depending on the goals of the researcher. From the biological literature, the concept of species that most closely matches the philosophical discussion presented here is Templeton's cohesion idea.

Biological Evolution↗
PubMed2003

Generally applicable fed-batch culture concept based on the detection of metabolic state by on-line balancing.

In many microorganisms, flux limitations in oxidative metabolism lead to the formation of overflow metabolites even under fully aerobic conditions. This can be avoided if the specific growth rate is controlled at a low enough value. This is usually accomplished by controlling the substrate feeding profile in a fed-batch process. The present work proposes a control concept which is based on the on-line detection of metabolic state by on-line calculation of mass and elemental balances. The advantages of this method are: 1) the check of measurement consistency based on all of the available measurements, 2) the minimum requirement of a priori knowledge of metabolism, and 3) the exclusive use of simple and established on-line techniques which do not require direct measurement of the metabolite in question. The control concept has been linked to a simple adaptive controller and applied to fed-batch cultures of S. cerevisiae and E. coli, organisms which express different overflow metabolites, ethanol and acetic acid, respectively. Oxidative and oxidoreductive states of S. cerevisiae and E. coli cultures were detected with high precision. As demonstrated by the formation of acetic acid in E. coli cultures, metabolic states could be correctly distinguished for systems for which traditional methods, such as respiratory quotient (RQ), are insensitive. Hence, it could be shown that the control concept allowed avoidance of overflow metabolite formation and operation at maximum oxidative biomass productivity and oxidative conversion of substrate into biomass. Based on mass and elemental balances, the proposed method additionally provides a richness of additional information, such as yield coefficients and estimation of concentrations and specific conversion rates. These data certainly help the operator to additionally evaluate the state of the process on-line.

Adaptation, Physiological↗
PubMed1989

Hepatic enzymic zonation: a reevaluation of the concept of the liver acinus.

The distribution pattern of a periportal enzyme (carbamoylphosphate synthetase) and a pericentral enzyme (glutamine synthetase) in human and rat liver has provided an objective parameter to delineate the zonal boundaries of the liver acinus. On sections, the pericental zone (zone 3) is circular and discrete rather than star-like and reticular, as predicted by the acinar concept, whereas the periportal zone (zone 1) is reticular, i.e. contiguous between adjacent acini rather than discrete. Three-dimensionally, the composite of pericentral zones (the pericentral compartment) follows the branching pattern of the terminal hepatic (central) vein, whereas the composite of periportal zones (the periportal compartment) envelops the pericentral compartment as a three-dimensional network (reticulum). This modified concept that is based upon the three-dimensional distribution of hepatocyte-specific enzymes is supported by data from the literature regarding the three-dimensional angioarchitecture of the liver, the perfusion pattern of the liver and the three-dimensional pattern of tissue oxygenation. Hence, a unified concept of the liver architecture that is based upon the observed distribution pattern of blood flow, of gene expression and of metabolism can be established.

Adult↗
PubMed2000

Regression and psychoanalytic technique: the concretization of a concept.

An exploration of the regression concept historically and conceptually reveals that its familiarity and frequent use have resulted in decreasing conceptual clarity and precision. Rooted in an outmoded fixation-regression model of development and psychopathology, the concept has become concretized. This paper is a beginning exploration of problematic aspects of the concept of regression, with emphasis on potentially detrimental consequences for psychoanalytic technique that derive from its unexamined use. Some of the salient issues are illustrated with clinical examples.

Adult↗
PubMed2002

A dual conception of narcissism: positive and negative organizations.

The author explores Freud's concept of narcissism, as well as other discussions of narcissism in the psychoanalytic literature. He introduces the dual conception of positive narcissism and negative narcissism, illustrated by two clinical vignettes. Subsequent discussion elaborates on these two types of narcissism, and also addresses life narcissism, death narcissism, and primary narcissism. The latter is considered in light of the influence of infant observational research on the prevailing view of this concept and the misunderstandings that arise from that approach.

Adult↗
PubMed2005

Introduction to the special issue on the placebo concept in psychotherapy.

As research on the effectiveness of psychotherapy has flourished over the past two decades, scholars have increasingly borrowed various research strategies, including the placebo concept, from medicine. The recent movement toward evidence-based treatment in mental health has also highlighted psychological placebos as control conditions against which to define empirically supported psychotherapies. Nevertheless, the application of the placebo concept to psychotherapy is fraught with both conceptual and pragmatic problems. This special issue brings together leading psychotherapy scholars to explore the concept of the placebo to psychotherapy. Historical, theoretical, ethical, and practical issues are discussed from various perspectives, and recommendations are offered to guide future research.

Empirical Research↗