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PubMed2003

Minding experience: An exploration of the concept of "experience" in the early French anthropology of Durkheim, Lévy-Bruhl, and Lévi-Strauss.

In line with the growing concern with the unexamined reliance upon the concept of "experience" in anthropology, this article explores in some detail the various usages and definitions of the concept in the work of three of early French anthropology's most influential theorists: Emile Durkheim (1858-1918), Lucien Lévy-Bruhl (1857-1939), and Claude Lévi-Strauss (1908-). With its important influence on both British and American anthropology, the early French anthropological tradition, as epitomized in the writings of these three thinkers, has indeed played a pivotal role in shaping many current taken-for-granted understandings of the concept of experience in the discipline of anthropology as a whole. In the process of exploring how experience is viewed by these three scholars, this paper will thus take some initial steps toward the historical contextualization of many of the unquestioned assumptions underpinning current understandings of experience in the discipline of anthropology and the social sciences more generally.

Anthropology↗

PubMed2004

Culture at work: Family therapy and the culture concept in post-World War II America.

During the 1950s and 1960s, the concept of culture had currency beyond the disciplinary boundaries of anthropology and sociology. This article takes up a clinical example of the invocation of the culture concept by examining how early family therapists such as Nathan Ackerman, Murray Bowen, and Don Jackson used culture as a category of analysis during the formative years of their new field. The culture concept played an integral role in the processes by which family therapists simultaneously defined the object of their research and treatment, the family, and built their new field. Their varied uses of culture also contained tensions and contradictions, most notably between universal and relativist views of family and psychopathology and between views of family therapy as a conservative force for maintaining the nuclear family or a progressive force for overcoming social inequality.

Culture↗

PubMed2003

Experimental demonstration that pre- and post-conceptional mechanisms influence sex ratio in mouse embryos.

Previously we have demonstrated in two monotocous species (bovine and sheep), a relationship between time of insemination, moment of ovulation, and embryo sex ratio. Here, we have analyzed in a polytocous specie (mice) if in addition to pre-conceptional mechanisms, also post-conceptional ones affect the offspring sex ratio. To verify this hypothesis we carried out two experiments. In the first experiment, we analyzed the effect of mating dynamics on the sex ratio of mice with synchronic male and female embryo development. Females were mated before and after ovulation and sacrificed 13 days later for sex determination of embryos and reabsorptions. A decreased litter size, and an increased offspring sex ratio in matings occurring later in oestrus, supported the view that a biased sex ratio may occur as the result of behavioral differences between the populations of X- or Y-bearing spermatozoa. In the second experiment, embryos developmentally synchronic and asynchronic with the recipient female endometrium were transferred, and again, 13 days later, females were sacrificed for sex determination of embryos and reabsorptions. The male proportion per litter found, indicated that our developmentally asynchronic transfers favored a sex ratio disbalance at birth. When combined, these results become the first experimental evidence supporting the view that both pre- and post-conceptional mechanisms of sex ratio distortion in polytocous species are not mutually exclusive and both may explain, under different conditions, sex ratio deviations at birth.

Animals↗

PubMed1996

Identification and application of the concepts important for accurate and reliable protein secondary structure prediction.

A protein secondary structure prediction method from multiply aligned homologous sequences is presented with an overall per residue three-state accuracy of 70.1%. There are two aims: to obtain high accuracy by identification of a set of concepts important for prediction followed by use of linear statistics; and to provide insight into the folding process. The important concepts in secondary structure prediction are identified as: residue conformational propensities, sequence edge effects, moments of hydrophobicity, position of insertions and deletions in aligned homologous sequence, moments of conservation, auto-correlation, residue ratios, secondary structure feedback effects, and filtering. Explicit use of edge effects, moments of conservation, and auto-correlation are new to this paper. The relative importance of the concepts used in prediction was analyzed by stepwise addition of information and examination of weights in the discrimination function. The simple and explicit structure of the prediction allows the method to be reimplemented easily. The accuracy of a prediction is predictable a priori. This permits evaluation of the utility of the prediction: 10% of the chains predicted were identified correctly as having a mean accuracy of > 80%. Existing high-accuracy prediction methods are "black-box" predictors based on complex nonlinear statistics (e.g., neural networks in PHD: Rost & Sander, 1993a). For medium- to short-length chains (> or = 90 residues and < 170 residues), the prediction method is significantly more accurate (P < 0.01) than the PHD algorithm (probably the most commonly used algorithm). In combination with the PHD, an algorithm is formed that is significantly more accurate than either method, with an estimated overall three-state accuracy of 72.4%, the highest accuracy reported for any prediction method.

Amino Acid Sequence↗

PubMed1999

Is a picture worth a thousand words? Evidence from concept definitions by patients with semantic dementia.

Nine patients with semantic dementia (the temporal lobe variant of frontotemporal dementia) were asked to define concrete concepts either from presentation of a picture of the object or from its spoken name. As expected, the patients with the most severe semantic impairment produced the least detailed definitions, and the quality of the definitions overall was significantly related to concept familiarity. Further analyses of the definitions were designed to assess two key theoretical aspects of semantic organization. (i) Do objects and their corresponding names activate conceptual information in two neuroanatomically separable (modality-specific) semantic systems? If so, then-apart from any expected commonality in performance attributable to factors such as concept familiarity-one would not predict striking item-specific similarities in a patient's picture- and word-elicited definitions. (ii) Do sensory/perceptual features and more associative/functional attributes of conceptual knowledge form two neuroanatomically separable subsystems? If so, then one would predict significant dissociations in the prominence of these two types of information in the patients' definitions. The results lead us to favor a model of the semantic system that is divided by attribute type but not by modality.

Aged↗

PubMed1996

Self-concept and questions of life: identity development during late adolescence

The purpose of the present study was to explore identity development in late adolescent (18-20) years. Three areas were examined: (a) self-concept, (b) existential questions; content and communication patterns, and (c), connections between (a) and (b). The population consisted of 44 Swedish college students. Three methods were used: a questionnaire, the writing of a short essay and a self-evaluation test, Structural Analysis of Social Behavior (SASB). The results demonstrated a positive and stable self-concept for the majority of the group, and that questions of life mainly concerned questions of future. The quality of the self-concept (positive vs. negative) was significantly related to how subjects experienced adults' interest in their existential questions. Several issues are discussed: the importance of the social environment for identity development not only during early childhood but also during adolescence, the use of the SASB method in this age group and the need for placing processes of integration into focus in research concerning late adolescence.

Journal Article↗

PubMed1998

Conceptions of success: their correlates with prosocial orientation and behaviour in Chinese adolescents.

Data from a sample of 673 Chinese adolescents lent support to the hypothesis that conceptions of success or achievement goals affect both the inclination to and the actual performance of prosocial acts. With regard to attitude, it was found that: (a) task orientation (belief that success is gaining skill or understanding) and collaboration orientation (belief that success is working productively with one or more collaborators) increased with the inclination to help others, to co-operate and share things with others, to maintain an affective relationship with others, and to behave in compliance with social norms; and (b) ego orientation (belief that success is establishing one's competence as superior) was not generally associated with the inclination to perform prosocial acts. With regard to action, it was found that task orientation and collaboration orientation, but not ego orientation, increased with the number of normative and altruistic acts in the past year. The similarity between the belief-attitude correlation and the belief-action correlation indicates the robustness of the influence of conceptions of success. Also, sex differences and grade differences in the relationship between conceptions of success and prosocial and antisocial behaviours were found. Implications of the findings are discussed.

Achievement↗

PubMed2001

Symbolic representation of anatomical knowledge: concept classification and development strategies.

In this paper a novel approach to anatomy knowledge representation is described. The focus of the present research has been on the development of a representational framework where the conceptual level has been implemented by using hierarchical and nonhierarchical conceptual networks. This has allowed handling the demand for multiple views of anatomy (systemic and topographical views). The terminological level of the knowledge representation has been implemented by using a compositional strategy which has avoided the explicit storage of the terms used to express composite concepts. Hierarchical relations and composite concept representations have required supervision of both the inheritance and concept reconstruction. For this purpose heuristic knowledge has been stored in terms of consistency rules in the knowledge base. As proof of the capability of this system, we show how the knowledge base has been used to provide symbolic access to spatial information consisting of a reduced set of images from the Visible Human Dataset.

Anatomy, Cross-Sectional↗

PubMed1999

Understanding the Dynamics of Leadership: The Role of Follower Self-Concepts in the Leader/Follower Relationship.

In this paper we integrate recent theory and research on the self-concept with leadership theory. We conceptualize the self as being defined at three levels: the individual, interpersonal, and group levels. The effects of the self on information processing and behavior are mediated by the working self-concept, which is composed of self-views, possible selves, and goals (standards). Leaders are seen as producing short-run changes by influencing the working self-concept and more enduring changes through the development of chronic schema. Subordinates are also seen as influencing leaders' self-schema, both individually and collectively. Both practical and theoretical implications of this perspective are discussed. Copyright 1999 Academic Press.

Journal Article↗

PubMed1997

Revisiting Strategic Models of Evolution: The Concept of Neighborhood Invader Strategies

In game-theoretic or strategic models of species evolution, the phenotype of individual organisms in a population are regarded as alternate strategies for playing a competitive game. The evolutionary outcome is predicted to conform to the "solution" of that game. The most usual solution concept adopted for the evolutionary game is that of Maynard Smith, the so-called "evolutionary stable strategies" (ESS). In this paper we explore an alternative solution concept. We call it neighborhood invader strategy (NIS). A NIS is a phenotype which is capable of invading all established populations of its neighbors. This phenotype need not be, at the same time, an ESS; and the reverse is true as well. We shall analyze this concept for a single species whose evolutionary-possibility set is a one-dimensional continuum. Copyright 1997 Academic Press

Journal Article↗

PubMed1978

The receptor concept: prejudice, prediction, and paradox.

Major progress has been achieved in understanding the chemical nature of receptors for certain hormones and neurotransmitters. Some of these units have been obtained as homogenous proteins; concept and technology are adequate to permit the detailed chemical and structural analysis of these macromolecular units. The critical problem which now arises is to define how a receptor once "occupied" and "activated" serves to initiate action. Elucidation of details of receptor structure, in of itself, will not solve the "coupling problem" in hormone action. New concepts, as well as new technics, will probably be necessary. In this discussion I have raised the possibility that metals coordinated to hormone receptor complexes may be the "trigger" element involved in initiating action, serving to alter the state of functional units in binary fashion. In effect, the metal determines whether the "state" of the system is active or inactive. As stated previously in connection with the action of steroid hormone receptor complexes, the specific suggestions made relating metals to the hormone coulping process have been advanced primarily to illustrate the conceptual gap which exists with respect to "coupling." The present suggestions may prove to be correct or untenable, in whole or in part. If it turns out that metals play a central role in the coupling process of hormone action, perhaps via completely different mechanisms than those suggested here, one of the central ideas of receptor action developed by the pioneers who created the receptor concept will have been resurrected in principle, if not in detail. In science, as in life generally, conceptual progress once achieved sometimes turns out to be the rediscovery of the past.

Adenylyl Cyclases↗

PubMed1985

Life style--an emergent concept in the sociomedical sciences.

The concept of life style recently has gained prominence in sociomedical research; yet the term remains poorly defined. This paper traces the evolution of the life style concept from its origins in sociological and personality studies to its current use in reference to behavioral risk factors for disease. Particular attention is given to the changes in meaning that have taken place over the past few decades. Similarities between the notion of life style and concepts of cultural integration are noted, and the various uses of life style are categorized along an idealist-materialist continuum. Finally, the authors fault medicalized notions of life style for failing to acknowledge the importance of the context and meaning of health-related behavior.

Attitude to Health↗

PubMed1992

Genetic concepts in Greek literature from the eighth to the fourth century B.C.

A review of the concepts of genetics found in epic, historical and dramatic ancient Greek writings from the eighth to the fourth centuries B.C., is presented. The derived data suggest that the development of genetical concepts and ideas started with the praise of the heroes' divine or noble origin in Homer's epic poems (eighth century B.C.). It continued in the tracing of the descent and vicissitudes of the families of the Greek gods and the common ancestry of the Greek tribes as described in Hesiod's genealogical poems (around 700 B.C.), in the statement of descent and dual parenthood of leaders and kings in the books of Herodotus and Xenophon (fifth and fourth centuries B.C.), and in the concern about the lineage of the tragic figures in Greek drama (fifth century B.C.). The genetical concepts expressed in these writings most probably reflected popular notions of that time. They must, therefore, have been the basis of the perceptions and theories on heredity and procreation expressed by the ancient physicians and philosophers in the fifth and fourth centuries B.C., which in turn influenced the development of genetics for many centuries.

Child↗

PubMed1987

The phenomenon of stress: concepts and mechanisms associated with stress-induced responses of the neuroendocrine system.

'Stress', 'stressors' and the 'stress response' are terms which represent concepts rather than being precisely definable. No single theory of stress has been universally accepted. Selye's General Adaptation Syndrome of stress remains the primary theory for the basis of stress research in food-producing animals; however, other concepts and theories have been developed. This paper reviews current theories and suggests that the complexity of research on stress in food-producing animals can be attributed to the lack of concrete theories and concepts regarding identifiable stressors, the endocrine responses stimulated by potential stressors and the complex and integrated biological changes in the neuro-endocrine system resulting from exposure to hypothesized stressors.

Animals↗

PubMed1988

Vitamin D--soltriol the heliogenic steroid hormone: somatotrophic activator and modulator. Discoveries from histochemical studies lead to new concepts.

Evidence from autoradiographic studies with 3H 1,25(OH)2 vitamin D3 (soltriol) about its many sites of nuclear binding and multiple actions suggests that the traditional view of "vitamin D and calcium" is too limited and requires modification. A new concept has been developed which proposes that the skin-derived hormone of sunshine, soltriol, is a somatotrophic activator and modulator that affects all vital systems. Regulation of calcium homeostasis is only one of its many actions. Target tissues for soltriol include not only bone, intestine and kidney, but also brain, spinal cord, pituitary, thyroid, endocrine pancreas, adrenal medulla, enteroendocrine cells, thymus, and male and female reproductive organs. Accordingly, actions of soltriol involve effects on autonomic and endocrine regulation with changes in tissue and blood hormone levels, innervation of skeletal muscle, immune and stress response, digestion, blood formation, fertility, pregnancy and lactation, general energy metabolism, mental processes and mood, and others. The skin-mediated transduction of short-wave sunlight induces a purposeful modulation of growth, reproduction and other biological activities in tune with the conditions of the sun cycle and season. Synthesis and actions of vitamin D3-soltriol are dependent not only on the amount of sunlight, but also on the availability of precursor in the skin and access of sunlight, the rate of hydroxylation in liver and kidney, and the modulation of these events by the endocrine status, in particular growth and reproduction. A concept of a five-level control of soltriol synthesis is proposed, in which the hydroxylation steps provide for a sensitive tuning. Relationships between the heliogenic skin-derived hormonal system and the helioprivic pineal-derived hormonal system are recognized and a comprehensive concept of the "endocrinology of sunlight and darkness" is pointed out.

Calcitriol↗

PubMed1993

Do we need a concept of disease?

The terms "health", "disease" and "illness" are frequently used in clinical medicine. This has misled philosophers into believing that these concepts are important for clinical thinking and decision making. For instance, it is held that decisions about whether or not to treat someone or whether to relieve someone of moral responsibility depend on whether the person has a disease. In this paper it is argued that the crucial role of the 'disease' concept is illusory. The health/disease distinction is irrelevant for most decisions and represents a conceptual straightjacket. Sophisticated and mature clinical decision making requires that we free ourselves from the concept of disease.

Clinical Medicine↗

PubMed1975

The concept of the effective dose--a proposal for the combination of organ doses.

Irradiation of the human body by external or internal sources leads mostly to a simultaneous exposure of several organs. However, so far no clear and consistent recommendations for the combination of organ doses and the assessment of an exposure limit under such irradiation conditions are available. Following a proposal described in ICRP-publication 14 one possible concept for the combination of organ doses is discussed in this paper. This concept is based on the assumption that at low doses the total radiation detriment to the exposed person is given by the sum of radiation detriments to the single organs. Taking into account a linear dose-risk relationship, the sum of weighted organ doses leads to the definition of an "Effective Dose". The applicability and consequences of this "Effective Dose Concept" are discussed especially with regard to the assessment of the maximum permissible intake of radionuclides into the human body and the combination of external and internal exposure.

Dose-Response Relationship, Radiation↗

PubMed1995

Rethinking neurasthenia: the illness concepts of shenjing shuairuo among Chinese undergraduates in Hong Kong.

Neurasthenia is both a Western disease construct and a popular Chinese illness concept (shenjing shuairuo, SJSR). Using a self-report questionnaire, we examined 148 Hong Kong Chinese undergraduates' concept of its epidemiology, symptomatology, etiology and treatment. Notwithstanding that fatigue is the sine qua non of neurasthenia in Western nosology, subjects believed that SJSR was compatible with a diversity of symptoms which fell, on factor analysis, into the "neurotic," "psychotic," "somatic" and "dysfunctional" subgroups. Contrary to the popular portrayal of SJSR as a physical or chronic fatigue disorder, the most common perceived symptoms were anxiety, insomnia, depression and fright. Logically, psychological etiology and remedy were highly emphasized. The perceived high prevalence, non-aggressive nature and symptomatic diversity of SJSR attested to the notion that it might camouflage and destigmatize psychiatric labels of insanity. The contextual study of neurasthenia illustrates how in its search for legitimacy an originally Western concept adapts, transforms, and acquires distinctive local meanings in a non-Western culture.

Adolescent↗