123 research outputs found
Editorial
Esta edição abre o ano do décimo aniversário da publicação da Revista Portuguesa e Brasileira de Gestão alicerçada numa parceria entre instituições de ensino em lÃngua portuguesa da doutrina e da prática do management adaptado à s condições especÃficas dos dois lados do Atlântico
High rate of extrapair paternity in a human population demonstrates diversity in human reproductive strategies
Among nonhuman species, social monogamy is rarely accompanied by complete fidelity. Evolutionary theory predicts that the rate of extrapair paternity (EPP) should vary according to socioecological conditions. In humans, however, geneticists contend that EPP is negligible and relatively invariable. This conclusion is based on a limited set of studies, almost all of which describe European-descent groups. Using a novel, double-blind method designed in collaboration with a community of Himba pastoralists, we find that the rate of EPP in this population is 48%, with 70% of couples having at least one EPP child. Both men and women were very accurate at detecting cases of EPP. These data suggest that the range of variation in EPP across human populations is substantially greater than previously thought. We further show that a high rate of EPP can be accompanied by high paternity confidence, which highlights the importance of disaggregating EPP from the notion of “cuckoldry.
Editorial - Os domÃnios «soft»
O conjunto de artigos que seleccionámos para integrar este último número da Revista de 2006, dá particular destaque a temáticas ainda pouco valorizadas nas ciências da gestão: a gestão dos activos intangÃveis, em geral, e a gestão do conhecimento e do marketing interno e a gestão do capital intelectual, em particular
Rotation Curves of Galaxies by Fourth Order Gravity
We investigate the radial behavior of galactic rotation curves by a Fourth
Order Gravity adding also the Dark Matter component. The Fourth Order Gravity
is a Lagrangian containing the Ricci scalar, the Ricci and Riemann tensor, but
the rotation curves are depending only on two free parameters. A systematic
analysis of rotation curves, in the Newtonian Limit of theory, induced by all
galactic sub-structures of ordinary matter is shown. This analysis is presented
for Fourth Order Gravity with and without Dark Matter. The outcomes are
compared with respect to classical outcomes of General Relativity. The
gravitational potential of point-like mass is the usual potential corrected by
two Yukawa terms. The rotation curve is higher or also lower than curve of
General Relativity if in the Lagrangian the Ricci scalar square is dominant or
not with respect to the contribution of the Ricci tensor square. The curves are
compared with the experimental data for the Milky Way and the galaxy NGC 3198.
Although the Fourth Order Gravity gives more rotational contributions, in the
limit of large distances the Keplerian behavior is present, and it is missing
if we add a Dark Matter component. By modifying the theory of Gravitation
consequently also the spatial description of Dark Matter could undergo a
modification. At last we compare the gravitational potential by Fourth Order
Gravity with respect to more used potential induced by power law of Ricci
scalar.Comment: 14 pages, 10 figure
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Variation Among Populations in the Immune Protein Composition of Mother\u27s Milk Reflects Subsistence Pattern
Lay Summary: Adaptive immune proteins in mothers’ milk are more variable than innate immune proteins across populations and subsistence strategies. These results suggest that the immune defenses in milk are shaped by a mother’s environment throughout her life.
Background and objectives: Mother’s milk contains immune proteins that play critical roles in protecting the infant from infection and priming the infant’s developing immune system during early life. The composition of these molecules in milk, particularly the acquired immune proteins, is thought to reflect a mother’s immunological exposures throughout her life. In this study, we examine the composition of innate and acquired immune proteins in milk across seven populations with diverse disease and cultural ecologies.
Methodology: Milk samples (n = 164) were collected in Argentina, Bolivia, Nepal, Namibia, Philippines, Poland and the USA. Populations were classified as having one of four subsistence patterns: urban-industrialism, rural-shop, horticulturalist-forager or agro-pastoralism. Milk innate (lactalbumin, lactoferrin and lysozyme) and acquired (Secretory IgA, IgG and IgM) protein concentrations were determined using triple-quadrupole mass spectrometry.
Results: Both innate and acquired immune protein composition in milk varied among populations, though the acquired immune protein composition of milk differed more among populations. Populations living in closer geographic proximity or having similar subsistence strategies (e.g. agropastoralists from Nepal and Namibia) had more similar milk immune protein compositions. Agropastoralists had different milk innate immune protein composition from horticulturalist-foragers and urban-industrialists. Acquired immune protein composition differed among all subsistence strategies except horticulturist-foragers and rural-shop.
Conclusions and implications: Our results reveal fundamental variation in milk composition that has not been previously explored in human milk research. Further study is needed to understand what specific aspects of the local environment influence milk composition and the effects this variation may have on infant health outcomes
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Variation among populations in the immune protein composition of mother's milk reflects subsistence pattern
Lay summaryAdaptive immune proteins in mothers' milk are more variable than innate immune proteins across populations and subsistence strategies. These results suggest that the immune defenses in milk are shaped by a mother's environment throughout her life.Background and objectivesMother's milk contains immune proteins that play critical roles in protecting the infant from infection and priming the infant's developing immune system during early life. The composition of these molecules in milk, particularly the acquired immune proteins, is thought to reflect a mother's immunological exposures throughout her life. In this study, we examine the composition of innate and acquired immune proteins in milk across seven populations with diverse disease and cultural ecologies.MethodologyMilk samples (n = 164) were collected in Argentina, Bolivia, Nepal, Namibia, Philippines, Poland and the USA. Populations were classified as having one of four subsistence patterns: urban-industrialism, rural-shop, horticulturalist-forager or agro-pastoralism. Milk innate (lactalbumin, lactoferrin and lysozyme) and acquired (Secretory IgA, IgG and IgM) protein concentrations were determined using triple-quadrupole mass spectrometry.ResultsBoth innate and acquired immune protein composition in milk varied among populations, though the acquired immune protein composition of milk differed more among populations. Populations living in closer geographic proximity or having similar subsistence strategies (e.g. agro-pastoralists from Nepal and Namibia) had more similar milk immune protein compositions. Agro-pastoralists had different milk innate immune protein composition from horticulturalist-foragers and urban-industrialists. Acquired immune protein composition differed among all subsistence strategies except horticulturist-foragers and rural-shop.Conclusions and implicationsOur results reveal fundamental variation in milk composition that has not been previously explored in human milk research. Further study is needed to understand what specific aspects of the local environment influence milk composition and the effects this variation may have on infant health outcomes
The effectiveness and satisfaction of web-based physiotherapy in people with spinal cord injury: a pilot randomised controlled trial
Study Design: Pilot randomised controlled trial.
Objectives: The aims of this study were to evaluate the effectiveness and participant satisfaction of web-based physiotherapy for people with Spinal Cord Injury (SCI).
Setting: Community patients of a national spinal injury unit in a university teaching hospital, Scotland, UK.
Methods: Twenty-four participants were recruited and randomised to receive eight weeks of web-based physiotherapy (intervention), twice per week, or usual care (control). Individual exercise programmes were prescribed based upon participant’s abilities. The intervention was delivered via a website (www.webbasedphysio.com) and monitored and progressed remotely by the physiotherapist.
Results: Participants logged on to the website an average of 1.4±0.8 times per week. Between-group differences, although not significant were more pronounced for the 6 minute walk test. Participants were positive about using web-based physiotherapy and stated they would be happy to use it again and would recommend it to others. Overall it was rated as either good or excellent.
Conclusions: Web-based physiotherapy was feasible and acceptable for people with SCI. Participants achieved good compliance with the intervention, rated the programme highly and beneficial for health and well-being at various states post injury. The results of this study warrant further work with a more homogenous sample
Patterns of Paternal Investment Predict Cross-Cultural Variation in Jealous Response
Long-lasting, romantic partnerships are a universal feature of human societies; but almost as ubiquitous is the risk of instability that comes when one partner strays. Jealous response to the threat of infidelity is a well-studied phenomenon, but most empirical work on the topic has focused on a proposed sex difference in the type of jealousy (sexual or emotional) men and women find most upsetting, rather than on how jealous response varies1,2. This stems in part from the predominance of studies using student samples from industrialized populations, which represent a relatively homogenous group in terms of age, life history stage, and social norms3,4. To better understand variation in partner jealousy, we conducted a two-part study in 11 populations (1,048 individuals), including eight small-scale societies, which examines how both sex and culture affect perceptions of infidelity. We show that, in spite of a robust sex difference, variation in jealous response is impacted more by the culture a respondent belongs to than by their sex. We further identify paternal investment and frequency of extramarital sex as two key predictors of cultural variation. Partner jealousy thus appears to be a facultative response, in part reflective of the variable risks and costs of men’s investment across societies
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