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At least 757 records · Page 42Linked to original sources
PubMed1996

[Hospital infections in Brazil. Government actions for their control as expressions of social politics in the health area].

The authors study the hospital infections evolution em Brasil and the demands for its control until its establishment by governmental actions. For a better understanding and analysis of the social actors' dispute process, their needs and interests and the relation with the governmental sector to the establishment of a certain state politics, a theoretical reference that enabled to elaborate the whole of social structure elements was searched. This theoretical reference should also take the filled of the relation between Society, State, Actors and Social Politics as its main question. In order to allude to these specific actions and its intervention range, it was necessary to make a distinction between the state politics modalities and the implementation responsibilities. Based on empirical material, it was possible to trace these demands, conforming on technological-assistencial models thorough the working process indicators. Other empirical categories levels was demanded to approach to the theoretical reference: specific conjectures, welfare medical assistance, the clinical intervention model and the quality movement. All the time, the analysis of the demands and the established project aimed the relation between the instruments and their purposes with themselves and with the health general politics, showing its implications.

Brazil↗
PubMed2002

Social intelligence, innovation, and enhanced brain size in primates.

Despite considerable current interest in the evolution of intelligence, the intuitively appealing notion that brain volume and "intelligence" are linked remains untested. Here, we use ecologically relevant measures of cognitive ability, the reported incidence of behavioral innovation, social learning, and tool use, to show that brain size and cognitive capacity are indeed correlated. A comparative analysis of 533 instances of innovation, 445 observations of social learning, and 607 episodes of tool use established that social learning, innovation, and tool use frequencies are positively correlated with species' relative and absolute "executive" brain volumes, after controlling for phylogeny and research effort. Moreover, innovation and social learning frequencies covary across species, in conflict with the view that there is an evolutionary tradeoff between reliance on individual experience and social cues. These findings provide an empirical link between behavioral innovation, social learning capacities, and brain size in mammals. The ability to learn from others, invent new behaviors, and use tools may have played pivotal roles in primate brain evolution.

Animals↗
PubMed2000

Multiple origins of eusociality among sponge-dwelling shrimps (Synalpheus).

As the most extreme expression of apparent altruism in nature, eusociality has long posed a central paradox for behavioral and evolutionary ecology. Because eusociality has arisen rarely among animals, understanding the selective pressures important in early stages of its evolution remains elusive. Employing a historical approach to this problem, we used morphology and DNA sequences to reconstruct the phylogeny of 13 species of sponge-dwelling shrimps (Synalpheus) with colony organization ranging from asocial pair-bonding through eusociality. We then used phylogenetically independent contrasts to test whether sociality was associated with evidence of enhanced competitive ability, as suggested by hypotheses invoking an advantage of cooperation in crowded habitats. The molecular, morphological, and combined data each strongly supported three independent origins of monogynous, multigenerational (eusocial) colony organization within this genus. Phylogenetically independent contrasts confirmed that highly social taxa, with strong reproductive skew, have significantly higher relative abundance within the host sponge than do less social taxa, a result that was robust to uncertainty in tree topology and varying models of character change. A similar tendency for highly social species to share their sponge with fewer congener species was suggestive, but not significant. Because unoccupied habitat appears to be limiting for many sponge-dwelling shrimp species, these data are consistent with hypotheses that cooperative social groups enjoy a competitive advantage over less organized groups or individuals, where independent establishment is difficult, and that enemy pressure is of central importance in the evolution of animal sociality.

Animals↗
PubMed2002

Scale-free networks in biology: new insights into the fundamentals of evolution?

Scale-free network models describe many natural and social phenomena. In particular, networks of interacting components of a living cell were shown to possess scale-free properties. A recent study((1)) compares the system-level properties of metabolic and information networks in 43 archaeal, bacterial and eukaryal species and claims that the scale-free organization of these networks is more conserved during evolution than their content.

Archaea↗
PubMed1998

[The sociomedical prevention of chronic bronchitis in workers in the mining industry].

High frequency of risk factors for origination of chronic bronchitis resulted in a striking growth of its prevalence among miners. Employment of the system of medical and social prophylaxis, especially during the stages of evolution of the malady, involving automatic diagnosis and prognostication, correction of immune disorders, recommendations toward adapting work to suit miners and assigning them to jobs for which they are suited--all this makes for reducing morbidity, permits saving the man-power resources making possible a rational distribution thereof among mining enterprises, which facts enable a substantial social and economic effect to be achieved.

Bronchitis↗
PubMed2000

Managed care and its implications for social work curricula reform: policy and research initiatives.

A multitude of social, economic, and health factors are forcing the health care industry to examine the effectiveness and efficiency of health and mental health care delivery. Managed care has emerged in this environment of cost containment, as a viable distributive mechanism for the allocation of health care resources. Schools of social work must consider additions and/or revisions to their curriculum, in order to adequately prepare social workers to practice in a managed care environment. A major barrier is the negative attitude held by many practitioners and educators towards managed care. This paper discusses the evolution of managed care, and the challenges to social work education, including the necessity for developing a more balanced view of managed care. Suggested curricular revisions are provided for two major content areas: policy and research.

Attitude of Health Personnel↗
PubMed1992

Oxytocin receptor distribution reflects social organization in monogamous and polygamous voles.

The neuropeptide oxytocin has been implicated in the mediation of several forms of affiliative behavior including parental care, grooming, and sex behavior. Here we demonstrate that species from the genus Microtus (voles) selected for differences in social affiliation show contrasting patterns of oxytocin receptor expression in brain. By in vitro receptor autoradiography with an iodinated oxytocin analogue, specific binding to brain oxytocin receptors was observed in both the monogamous prairie vole (Microtus ochrogaster) and the polygamous montane vole (Microtus montanus). In the prairie vole, oxytocin receptor density was highest in the prelimbic cortex, bed nucleus of the stria terminalis, nucleus accumbens, midline nuclei of the thalamus, and the lateral aspects of the amygdala. These brain areas showed little binding in the montane vole, in which oxytocin receptors were localized to the lateral septum, ventromedial nucleus of the hypothalamus, and cortical nucleus of the amygdala. Similar differences in brain oxytocin receptor distribution were observed in two additional species, the monogamous pine vole (Microtus pinetorum) and the polygamous meadow vole (Microtus pennsylvanicus). Receptor distributions for two other neurotransmitter systems implicated in the mediation of social behavior, benzodiazepines, and mu opioids did not show comparable species differences. Furthermore, in the montane vole, which shows little affiliative behavior except during the postpartum period, brain oxytocin receptor distribution changed within 24 hr of parturition, concurrent with the onset of maternal behavior. We suggest that variable expression of the oxytocin receptor in brain may be an important mechanism in evolution of species-typical differences in social bonding and affiliative behavior.

Animals↗
PubMed2005

Participation after spinal cord injury: the evolution of conceptualization and measurement.

The increasing life expectancy after spinal cord injury has given social participation a new recognition as one of the ultimate goals of a comprehensive rehabilitation process. Recent evolution of the concept suggests 2 different approaches to document participation after spinal cord injury and a careful appraisal of the related outcome measures is important as discrepancies of results between the 2 approaches can be significant. Literature on objective participation reports a large variability in several dimensions that are particularly influenced by intrinsic factors such as severity of injury and secondary impairments. The direct influence of the environmental factors remains to be demonstrated by empirical studies. There are fewer tools available to evaluate subjective impressions of participation but recent investigations support the importance of taking account of the person's perceived restrictions participation in order to get better understandings of an individual's specific needs and problems. The aim of this article is to present the evolution of the conceptualization and measurement of the two approaches and to describe the level of participation of individuals with SCI.

Activities of Daily Living↗
PubMed2001

On the relative importance of haplodiploidy, assortative mating and social synergy on the evolutionary emergence of social behavior.

Advances in multiagent simulation techniques make it possible to study more realistic dynamics of complex systems and allow evolutionary theories to be tested. Here I use simulations to assess the relative importance of reproductive systems (haplodiploidy vs. diploidy), mate selection (assortative mating vs. random mating) and social economics (pay-off matrices of evolutionary games) in the evolutionary dynamics leading to the emergence of social cooperation in the provision of parental care. The simulations confirm that haplo-diploid organisms and organisms mating assortatively have a higher probability for fixing alleles and require less favorable conditions for their fixation, than diploids or organisms mating randomly. The simulations showed that social behavior was most likely to emerge a) when the cost for parental investment was much lower than the benefits to the offspring, b) when cooperation improved synergistically the fitness of offspring compared to the corresponding egoistic behavior and c) when alleles coding for altruistic or social behavior could be rapidly fixed in the population, thanks to mechanisms such as haplo-diploidy and/or assortative mating. Cooperative social behavior always appeared if sociality conferred much higher fitness gains compared to non cooperative alternatives suggesting that the most important factors for the emergence and maintenance of social behavior are those based on energetic or efficiency considerations. The simulations, in congruence with the scant experimental evidence available, suggest that economic considerations rather than genetic ones are critical in explaining the emergence and maintenance of sociality.

Animals↗
PubMedDate not supplied

[Candida infections and their evolution in patients receiving parenteral feeding].

Parenteral nutrition has completely modified the prognosis in a variety of illnesses of digestive tract. The method is not devoid of complications, and septicemias, particularly those originated by fungii of the Candida species, have been informed to occur with an alarming frequency of up to 23%. The patient on parenteral nutrition is an ideal prey for this kind of infection, but if the technic and the metabolic control are brought down considerably. In 30 patients of the Department of Gastroenterology at the Hospital General, Centro Médico Nacional, Instituto Mexicano del Seguro Social, we have studied the frequency and evolution of Candida infections, detected before or during the treatment with parenteral nutrition to know the influence of the method on this type of host-parasite relationship. In the initial cultures 60% of the patients develop Candida in one or several regions; percentage increased to 63.3% at the end of 15 days and decreased spontaneously to 33% at the end of the treatment on the 30 patients we did not observe a septicemia due to Candida. We conclude that parenteral nutrition, while correcting the nutritional state of the patient, with a good technic, favors the spontaneous withdrawal of the fungii, without the necessary specific treatment.

Candidiasis↗
PubMedDate not supplied

[The mentally handicapped: what educational and (pre)occupational future? Study of the Genevan population of mentally handicapped capable of job placement].

Personal and structural variables appear to determine the school, the pre-professional and the professional cursus of 575 mentally handicapped adults living in Geneva. At a personal level, the I.Q. plays the principal role until about the age of 15. As soon as the question of the professional life arises, one has to take other factors into account: secondary disorders, sex and, above all, the social class. At the structural level, the evolution is quite clear: as soon as new institutions are created, they are filled to capacity, leading, year after year, to a greater segregation.

Adolescent↗
PubMed1986

The social worker's role on the institutional Ethics Committee.

As institutional Ethics Committees become more prevalent in hospitals, social workers will be serving as committee members. The evolution of IECs is reviewed; and their proposed functions of education, policy-development, case consultation and/or review are examined. Potential roles for social work in the implementation of each function are suggested.

Ethics↗
PubMed1974

Island models for takeover by a social trait facing a frequency-dependent selection barrier in a Mendelian population.

A population genetic model is presented for selection of a Mendelian trait controlling for cooperative behavior between unrelated conspecifics. Under simple and robust assumptions, such a trait will be selected on a frequency-dependent basis, with a critical threshold frequency (beta(2) (crit)) of the social trait which must be exceeded before favorable selection of this trait can occur. Existence of this threshold gives rise to a basic evolutionary problem as to how evolution from an asocial state (beta congruent with 0) to a social state (beta congruent with 1) can take place. A formal model of this evolution is proposed which rests on obstacles to random mixing (population viscosity). The key fact is the possibility that an initial local concentration of the social trait may be able to spread out under the joint effects of selection and migration and eventually take over a much larger species population. It is argued that this model is the first formal model to capture the ideas of Wright concerning group selection of an altruist trait in an island-structured population.

Genetics, Population↗
PubMed1996

Common endocrine and genetic mechanisms of behavioral development in male and worker honey bees and the evolution of division of labor.

Temporal polyethism is a highly derived form of behavioral development displayed by social insects. Hormonal and genetic mechanisms regulating temporal polyethism in worker honey bees have been identified, but the evolution of these mechanisms is not well understood. We performed three experiments with male honey bees (drones) to investigate how mechanisms regulating temporal polyethism may have evolved because, relative to workers, drones display an intriguing combination of similarities and differences in behavioral development. We report that behavioral development in drones is regulated by mechanisms common to workers. In experiment 1, drones treated with the juvenile hormone (JH) analog methoprene started flying at significantly younger ages than did control drones, as is the case for workers. In experiment 2, there was an age-related increase in JH associated with the onset of drone flight, as in workers. In experiment 3, drones derived from workers with fast rates of behavioral development themselves started flying at younger ages than drones derived from workers with slower rates of behavioral development. These results suggest that endocrine and genetic mechanisms associated with temporal polyethism did not evolve strictly within the context of worker social behavior.

Aging↗