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At least 685 records · Page 38Linked to original sources
PubMed1993

Between man and woman: the character of the lesbian.

Homosexuality, or inversion, is defined by medical discourses since the middle of the XIXth century, as a condition which radically marks individuals so labelled. Through those discourses, a figure, a character, is built. It is no longer precise sexual acts which are at stake, but the totality of the person, who has salient features, biological, psychological as well as behavioral. Those salient features are built on gender mixing, even on sexual characteristics mixing. The inverts, in such a definition, stress the bipolarity of sexes because they embody an intermediate state, the 'third sex'. But this conceptualisation implies also a reinforcement of the two poles of categorisation. Homosexuals do not follow 'the natural law' which defines men and women. Third part excluded from bicategorisation, indifferentiate freaks, those characters are analysers for social definitions of sexes, genders and their evolution.

Character↗
PubMed2007

Presence of soldier larvae determines the outcome of competition in a polyembryonic wasp.

Soldier-producing polyembryonic waSPS are the only social animals that develop as parasites inside the bodies of other insects. Characterizing the kin composition of broods is central to understanding the evolution of the soldier caste in these unique social insects. Here we studied the role of soldiers in mediating the outcome of competition among clones of the polyembryonic wasp Copidosoma floridanum. Soldier-producing female clones usually monopolized host resources, whereas soldierless male clones usually coexisted in hosts. Behavioural experiments further indicated that early-emerging soldiers are specialized to combat intraspecific competitors and later-emerging soldiers are specialized for defence against interspecific competitors. Taken together, our results point to intraspecific competition as a major selective force in the evolution of the soldier caste. Our data also present an evolutionary conundrum: given the benefit of soldiers, why are male clones functionally soldierless?

Animals↗
PubMed1998

Videotelephony-based services--the proven improvement of quality of life.

As described above, the research activities showed very promising and fascinating results. It could be observed that the presumed acceptance problems of elderly technology users are not larger than in other groups. What is more: the elderly user of videotelephony-based services is a very pragmatic user. He or she accepts the new service offer as long as he or she sees the benefits. Decision makers in the social field should not be afraid of this client group! All of the users were willing to pay for the service--up to three times their current communication costs. It seems that there is a market for both the network providers and the telecommunication manufacturers. Private social service provider organisations were the first to realise the potential of the videotelephony-based social support and care services. Some of them are already developing service design schemes and are eagerly awaiting affordable technology. To ensure equal accessibility to these kind of services financial support is necessary to address the needs of socially disadvantaged user groups. Moreover, policy makers should concentrate on the definition of quality requirements for different issues. At the same time, neutral control institutions have to be set up to overcome prejudices and prevent misuse. All in all the authors still believe that picture-based social support and care services are one solution for the increasing problems resulting from demographical and social changes in many industrial societies. The technical evolution and the rapidly decreasing costs will lead to the implementation of picture-based social support and care services within a very short time. Some large application projects are currently underway throughout Europe. What is more: in Frankfurt/Germany, for instance, the first commercially available picture-based service will be introduced to the public in the spring of 1997.

Aged↗
PubMed2006

Darwinian models of depression: a review of evolutionary accounts of mood and mood disorders.

Over the last ten years, there has been increased interest in the evolutionary origins of depressive phenomena. The current article provides a review of the major schools of thought that have emerged in this area. First, we consider important Darwinian explanations of depressed mood, including an integrative social risk hypothesis recently proposed by the authors. According to the social risk hypothesis, depression represents an adaptive response to the perceived threat of exclusion from important social relationships that, over the course of evolution, have been critical to maintaining an individual's fitness prospects. We argue, moreover, that in the ancestral environment, depression minimized the likelihood of exclusion by inducing: (i) cognitive hypersensitivity to indicators of social risk/threat; (ii) signaling behaviours that reduce social threat and elicit social support; and (iii) a generalized reduction in an individual's propensity to engage in risky, appetitive behaviours. Neurobiological support for this argument is also provided. Finally, we review three models that endeavour to explain the relationship between the adaptations that underlie depressed mood and clinically significant, depressed states, followed by a consideration of the merits of each.

Affect↗
PubMed2004

Is globalization undermining the welfare state? The evolution of the welfare state in developed capitalist countries during the 1990s.

The authors analyze the evolution of macro-indicators of social and economic well-being during the 1990s in the majority of developed capitalist countries, grouped according to their dominant political traditions since the end of World War II. Their analysis shows that, despite the economic globalization of commerce and finance, "politics still matters" in explaining the evolution of the welfare states and labor markets in these countries; the impact of the globalization of financial capital in forcing reductions in the financial resources available for welfare state purposes has been exaggerated.

Developed Countries↗
PubMed1995

[The Brazilian economy in the 80's and its impact on the living conditions of the population].

In the 80's the Brazilian economy underwent one of the most severe crises of its history, resulting in the stagnation of the gross national product and inflation rates such as never previously reported. Despite this unfavorable scenario social indicators have presented a positive evolution. This work shows that although the Brazilian family has adopted the over-use of the family work force as a strategy for facing this crisis on the work market, the evolution of both income and poverty in that period were poor. The increase of expenses and the transformation of the forms of implementation of public policy in the health and nutrition areas are shown to be decisive factors in the performance of social indicators.

Anthropometry↗
PubMedDate not supplied

Social phobia: an update.

The literature on social phobia is reviewed in this article. Social phobia has undergone considerable diagnostic evolution to reach its present form in DSM-IV. Its differential diagnosis includes panic disorder with agoraphobia, avoidant personality disorder, depression, and "shyness." Cross-cultural issues are important to consider because the disorder may manifest differently in different cultures and social settings. It is common, with a lifetime prevalence of 13.3% in the United States according to recent epidemiological studies. Underrecognition of social phobia remains an issue of concern. Comorbidity with other psychiatric disorders, including other anxiety disorders, depression, alcohol abuse, and personality disorders, frequently occurs. Current conceptualizations of the etiology of social phobia reflect psychodynamic theories and evidence from family and genetic studies, neurobiological research, and neuroimaging. Drugs such as monoamine oxidase inhibitors, selective serotonin-reuptake inhibitors, benzodiazepines, and beta3-adrenergic blockers have proven to be efficacious, as has cognitive-behavioral treatment, including group approaches.

Cross-Cultural Comparison↗
PubMed2025

Evolutionary Process Underlying Receptor Gene Expansion and Cellular Divergence of Olfactory Sensory Neurons in Honeybees.

Olfaction is crucial for animals' survival and adaptation. Unlike the strict singular expression of odorant receptor (OR) genes in vertebrate olfactory sensory neurons (OSNs), insects exhibit complex OR gene expression patterns. In honeybees (Apis mellifera), a significant expansion of OR genes implies a selection preference for the olfactory demands of social insects. However, the mechanisms underlying receptor expression specificity and their contribution to OSN divergence remain unclear. In this study, we used single-nucleus multiomics profiling to investigate the transcriptional regulation of OR genes and the cellular identity of OSNs in A. mellifera. We identified three distinct OR expression patterns, singular OR expression, co-expression of multiple OR genes with a single active promoter, and co-expression of multiple OR genes with multiple active promoters. Notably, ∼50% of OSNs co-expressed multiple OR genes, driven by polycistronic transcription of tandemly duplicated OR genes via a single active promoter. In these OSNs, their identity was determined by the first transcribed receptor. The divergent activation of the promoter for duplicated OR genes ensures the coordinated increased divergence of OSN population. By integrating multiomics data with genomic architecture, we illustrate how fundamental genetic mechanisms drive OR gene expansion and influence flanking regulatory elements, ultimately contributing to the cellular divergence of OSNs. Our findings highlight the interplay between gene duplication and regulatory evolution in shaping OSN diversity, providing new insights into the evolution and adaptation of olfaction in social insects. This study also sheds light on how genetic innovations contribute to the evolution of complex traits.

Animals↗
PubMed2001

The widening social class gap of preventive health behaviours in Spain.

As a way of forecasting future evolution of inequalities in disease burden and mortality, trends in preventive health behaviours by social class were examined. Using the Spanish National Health Survey from 1987 to 1997 the evolution of the Health Practices Index (smoking, alcohol consumption, physical exercise, sleep hours and the Quetelet index) is described for the Spanish non-institutionalised adult population. In the last 10 years the disadvantaged population of Spain (social class groups IV and V) has not opted for healthier behavioural choices. On the contrary the Health Practices Index figures have worsened during the study period. Conversely, the more affluent groups (social class groups I, II and III) have exhibited a net gain in the index. Due to this, an increase in the existing gap in health inequalities in Spain in terms of morbidity and mortality can be forecast for the near future. As time trends of a summary indicator of preventive health behaviours by social class have not been described in other countries, a replication of this study in different cultural, social and economic milieus could produce valuable information.

Adult↗
PubMed2006

Population demography and the evolution of helping behaviors.

Limited dispersal may favor the evolution of helping behaviors between relatives as it increases their relatedness, and it may inhibit such evolution as it increases local competition between these relatives. Here, we explore one way out of this dilemma: if the helping behavior allows groups to expand in size, then the kin-competition pressure opposing its evolution can be greatly reduced. We explore the effects of two kinds of stochasticity allowing for such deme expansion. First, we study the evolution of helping under environmental stochasticity that may induce complete patch extinction. Helping evolves if it results in a decrease in the probability of extinction or if it enhances the rate of patch recolonization through propagules formed by fission of nonextinct groups. This mode of dispersal is indeed commonly found in social species. Second, we consider the evolution of helping in the presence of demographic stochasticity. When fecundity is below its value maximizing deme size (undersaturation), helping evolves, but under stringent conditions unless positive density dependence (Allee effect) interferes with demographic stochasticity. When fecundity is above its value maximizing deme size (oversaturation), helping may also evolve, but only if it reduces negative density-dependent competition.

Altruism↗
PubMed1997

The evolution of insect societies.

The organization and evolution of insect societies has amazed natural historians since Aristotle. Charles Darwin considered social insects to be a major difficulty for his theory of evolution by natural selection because they demonstrate a rich diversity of adaptation among sterile workers leading to a complex division of labour, something that should not occur if variation in individual reproductive success is the grist for the mill of natural selection. This article shows how division of labour can self-organize from groups of cohabiting individuals without the necessity of a past history of natural selection for co-operative behaviour. It then explores how more complex social systems may evolve.

Adaptation, Physiological↗
PubMedDate not supplied

[Economic crisis and infant mortality in Latin America since the 1980's].

In the present study, based on data from nine Latin American countries, we found evidence of an association between the economic crisis and infant mortality during the last decades. The paper initially review previous studies on this issue and shows the need for a greater research focus on shorter time intervals. We then describe the deterioration and unequal conditions among the countries based on trends in selected social and economic indicators and the evolution of infant mortality rates. According to our statistical analysis, infant mortality bore an inverse association to short-term economic variations. We also found a significant and negative correlation between decreasing infant mortality rates and increasing poverty. The economic crisis displayed effects of varying intensity among the countries we analyzed, with social inequality appearing as the most probable explanatory variable.

Economics↗
PubMed1977

Changes in Cuban health care: an argument against technological pessimism.

Since the popular revolution in 1959, alterations in the organization and delivery of health care in Cuba have paralleled the country's broader political, economic, and social changes. This paper discusses the evolution of the Cuban health care system during the past seventeen years within the wider context of societal development. The authors compare three "snapshots" of Cuba, the first in 1959, the second in 1970, and the last in 1976, and touch upon such issues as the organization of health care delivery, the recruitment and socialization of health workers, and aspects of the process of receiving health care. They point out that the Cuban experience should be of particular interest to the developing world. For though it is true that a larger portion of Cuban national resources has been directed to the health and social services than in other developing countries, nonetheless, it was largely through the reorganization and equalization of the prerevolutionary health care system that improvement in the health status of the population was achieved. It appears that Cuba could well serve as an example for those who are skeptical about the possibility of combining technical development with improvement in the humane quality of care.

Cuba↗
PubMed1984

Is there really a schizophrenia? The long-term course of psychotic phenomena.

The author fundamentally questions the traditional concept of the disease-entity (or several disease entities) of 'schizophrenia' and discusses an alternative concept, based on vulnerability and information-processing. According to this, schizophrenia-like psychotic phenomena develop in three phases. In the first, premorbid phase, combined biological (genetic and possibly other organic) and psycho-social influences lead to a premorbid 'vulnerability', characterised by a low tolerance of cognitive and emotional stress, corresponding to an insufficient capacity for the adequate processing of complex information. In the second phase, stressful life-events can lead to unique or repeated acute productive psychotic episodes. The third phase, that of long-term evolution, depends more on psycho-social influences than on biological factors. Under unfavourable conditions, it may lead to predominantly unproductive residual states of various degrees, which can largely be understood as regulatory mechanisms to restrict stressful over-stimulation. There is no clearly delimitable disease entity of schizophrenia with constant causes, psychopathological picture, or course, but rather a multi-conditioned life-process, occurring in people with a particular vulnerability, interacting with complex life-events and circumstances. This new concept has important consequences for therapy and prevention.

Adult↗
PubMed2004

Tolerance to unfamiliar conspecifics varies with social organization in female African mole-rats.

Intolerance to familiar conspecifics characterises solitary mole-rats and distinguishes them from social ones. However, no study has compared the patterns of tolerance to unfamiliar conspecifics. Theoretically, both solitary and social species should react similarly and show intolerance to unfamiliar same-sex conspecifics, unless the evolution of grouping has favoured higher tolerance to conspecifics among the social species. Our study compares tolerance to unfamiliar conspecifics in four African mole-rat species exhibiting varying degrees of sociality. Dyadic encounters between female unfamiliar conspecifics were performed in a neutral arena, and the assessment of social tolerance was based on both behavioural observations of amicable contact behaviour as opposed to aggression and avoidance behaviour and the assessment of a stress response to the encounter measured as an increase in plasma cortisol concentrations. Our results show that the two highly social species and the solitary one presented similar high levels of agonistic behaviours during encounters with unfamiliar conspecifics. Nevertheless, all three social species displayed social tolerance and did not show a stress arousal during encounters with unfamiliar conspecifics, a pattern that contrasted significantly with that evidenced in the solitary species. The results suggest that physiological and behavioural characteristics allow a higher tolerance to unfamiliar conspecifics in the social as opposed to the solitary mole-rat, and the adaptive value of these characteristics are discussed. Finally, we discuss why constraints on social tolerance may be an important limiting factor to take into account in theories concerning the evolution of grouping.

Agonistic Behavior↗
PubMed1975

[Long-term development of neurotic and reactive disorders. Catamnestic study on the influence of social factors].

This study enters into the framework of long term catamnestic researches realised at Hopital de Cery in Lausanne. In this work, the evolution of neurotic and reactionnal disorders in old age has been studied through the direct catamnestic examination of 35 patients who outlived 65 years of age. The accent has been particularly put on social and psychological evolution in regard to 15 variables responding to 2 fondamental hypotheses; it is the conducting clue of the work. After discussion concerning the working method and the selection of survey material, the author is analysing the 35 patients' main caracteristics at the time of their first hospitalisation. He is also taking interest on the patients' social surroundings during their childhood until they were 15. The notion of "broken-home" is largely discussed. The various evolutive aspects are firstly treated apart and then all together in regard to 15 mentioned variables. The various results are making the subject of statistic validation.

Affective Symptoms↗
PubMed2005

Juvenile hormone, reproduction, and worker behavior in the neotropical social wasp Polistes canadensis.

Previous studies of the division of labor in colonies of eusocial Hymenoptera (wasps and bees) have led to two hypotheses regarding the evolution of juvenile hormone (JH) involvement. The novel- or single-function hypothesis proposes that the role of JH has changed from an exclusively reproductive function in primitively eusocial species (those lacking morphologically distinct queen and worker castes), to an exclusively behavioral function in highly eusocial societies (those containing morphologically distinct castes). In contrast, the split-function hypothesis proposes that JH originally functioned in the regulation of both reproduction and behavior in ancestral solitary species. Then, when reproductive and brood-care tasks came to be divided between queens and workers, the effects of JH were divided as well, with JH involved in regulation of reproductive maturation of egg-laying queens, and behavioral maturation, manifested as age-correlated changes in worker tasks, of workers. We report experiments designed to test these hypotheses. After documenting age-correlated changes in worker behavior (age polyethism) in the neotropical primitively eusocial wasp Polistes canadensis, we demonstrate that experimental application of the JH analog methoprene accelerates the onset of guarding behavior, an age-correlated task, and increases the number of foraging females; and we demonstrate that JH titers correlate with both ovarian development of queens and task differentiation in workers, as predicted by the split-function hypothesis. These findings support a view of social insect evolution that sees the contrasting worker and queen phenotypes as derived via decoupling of reproductive and brood-care components of the ancestral solitary reproductive physiology.

Aging↗