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PubMed2005

Affiliation promotes the transmission of a social custom: handclasp grooming among captive chimpanzees.

Handclasp grooming is a unique social custom, known to occur regularly among some, but not all populations of chimpanzees (Pan troglodytes). As with other cultural behaviors, it is assumed that this distinctive grooming posture is learned socially by one individual from another. However, statistical comparisons among factors thought to influence how a behavior spreads within a group have never, to our knowledge, been conducted. In the present study, the origination and spread of handclasp grooming in a group of captive chimpanzees was followed throughout more than 1,500 h of observation over a period of 12 years. We report on the frequency, bout duration, and number and demography of performers throughout the study period, and compare these findings to those reported for wild populations. We predicted that dyads with strong affiliative ties, measured by time spent in proximity to and grooming one another, were likely to develop a handclasp grooming partnership during the study period. A quadratic assignment procedure was used to compare correlations among observed frequencies of grooming and proximity with handclasp grooming in all possible dyads within the group. As predicted, the formation of new handclasp grooming dyads was positively correlated with the rate of overall grooming and proximity within a dyad. In addition, in nearly all dyads formed, at least one individual had been previously observed to handclasp groom. We concluded that affiliation and individual experience determines the transmission of handclasp grooming among captive chimpanzees.

Animals↗
PubMed2006

Isolation and characterization of a novel bacterium, Sphingomonas bisphenolicum strain AO1, that degrades bisphenol A.

Bisphenol A (2,2-bis(4-hydroxyphenyl) propane, BPA), which is used as a synthetic resin material or a plasticizer, is a pollutant that possesses endocrine-disrupting activity. Bioremediation of BPA is used to decrease its polluting effects, and here we report a novel bacterial strain AO1, which is able to degrade BPA. This strain was isolated using enrichment cultivation from a soil sample from a vegetable-growing field; the sample was one of 500 soil samples collected across Japan. Strain AO1 degraded 100 mg/l BPA to an undetectable level within 6 h in MYPG medium (containing malt extract, yeast extract, peptone, and glucose) and within 48 h in minimum medium containing 1% glucose at 30 degrees C. Strain AO1 can utilize BPA as a sole source of carbon and as an energy source under aerobic conditions. The estrogenic activity of BPA in MYPG medium was ultimately reduced by strain AO1, although the activity initially increased. Taxonomical analysis showed that strain AO1 is closely related to Sphingomonas chlorophenolicum and S. herbicidovorans, neither of which have a capacity for BPA degradation. DNA-DNA hybridization showed that strain AO1 is a novel species of the Sphingomonas genus, and we designated AO1 as S. bisphenolicum.

Benzhydryl Compounds↗
PubMed2006

Analysing structural and cultural change in acute settings using a Giddens-Weick paradigmatic approach.

An examination of the salient literature on hospital clinical directorates (CDs) is presented. A critique of the largely managerialist, instrumental, hortatory and normative extant literature about CDs is offered. In analysing the literature this way the earlier promotional and critical literature is eschewed in favour of an evaluative approach. CDs are then reconceptualised by locating them within two overarching accounts of social structure--formalised, prescribed frameworks, and enacted, patterned interactions--following the kinds of distinctions made by Giddens, Weick, social action and institutional theorists. Social structure as it relates to culture is also considered, following Martin. Such an approach facilitates an understanding of the general weaknesses of health service perspectives and methods of analysis, and exposes the strengths of Giddens-Weick type paradigms.

Acute Disease↗
PubMed1990

Interspecific hybridization between an anural and urodele ascidian: differential expression of urodele features suggests multiple mechanisms control anural development.

Anural development in the ascidian Molgula occulta was examined using tissue-specific markers and interspecific hybridization. Unlike most ascidians, which develop into a swimming tadpole larva (urodele development), M. occulta eggs develop into a tailless slug-like larva (anural development) which metamorphoses into an adult. M. occulta embryos show conventional early cleavage patterns, gastrulation, and neurulation, but then diverge from the urodele developmental mode during larval morphogenesis. M. occulta larvae do not contain a pigmented sensory cell in their brain or form a tail with differentiated notochord and muscle cells. As shown by in situ hybridization with cloned probes and analysis of in vitro translation products, M. occulta embryos do not accumulate high levels of alpha actin or myosin heavy chain mRNA. In contrast, acetylcholinesterase is expressed in muscle lineage cells, indicating that various muscle cell features are differentially suppressed. M. occulta embryos also lack tyrosinase activity, suggesting that suppression of brain pigment cell differentiation occurs at an early step in development. M. occulta eggs fertilized with sperm from Molgula oculata (a closely related urodele species) develop into hybrid larvae exhibiting some of the missing urodele features. Some hybrid embryos develop tyrosinase activity and differentiate a brain pigment cell and a short row of notochord cells, and form a short tail. These urodele features appeared together or separately in different hybrid embryos suggesting that they develop by independent mechanisms. In contrast, alpha actin and myosin heavy chain mRNA accumulation was not enhanced in hybrid embryos. These results suggest that multiple mechanisms control anural development.

Animals↗
PubMed1994

Considerations of human's long stay in closed systems.

Conditions for long stay of human in closed systems with material circulation, such as space stations and lunar bases, are discussed compared with the current human's life style on earth in the light of human cultural history. Impact on the life-style in the closed ecological system lies on meals and hygiene systems. A key to resolve problems in a new life-style in a closed system lies on mental aspects relating to a new life culture. Necessary items to be developed are shown in order to realize comfortable life in the closed system.

Cultural Evolution↗
PubMed1992

Conversion in the peptides coating cadmium:sulfide crystallites in Candida glabrata.

Cultures of Candida glabrata treated with CdCl2 form intracellular Cd(II) complexes that evolve with the time of culturing. Initially, glutathione (gamma ECG) appears to be the major buffering component. One type of Cd(II)-glutathione complex exists as a cadmium:sulfide (CdS) crystallite coated with glutathione. A time dependent change in the coating of the CdS particles occurs with a decrease in the (gamma ECG) content and a corresponding increase in the abundance of (gamma EC)nG peptides with (gamma EC)2G becoming the predominant peptide. The des-Gly variant (gamma EC)2 appears in significant concentration only in late cultures. The evolution in isopeptide coating appears to be dependent on the sulfide content of the CdS particles. Cellular conditions that enhance the generation of sulfide ions facilitate the conversion from gamma ECG to (gamma EC)2G.

Buffers↗
PubMed1992

Cultural change and the reproductive cycle.

What we regard as 'normal' or 'natural' with respect to human female reproductive physiology differs greatly from the reproductive cycle experienced during most of human existence. Frequent ovulatory menstrual cycles really represent repeated abortive reproductive cycles and are unphysiological. A number of medical conditions, some of great importance, are the result of this change in the character of the reproductive cycle. Suppression of the menstrual cycle offers a means of decreasing the incidence and severity of these medical conditions.

Animals↗
PubMed1996

Leprosy among the Limba: illness and healing in the context of world view.

The study analyzes the traditional beliefs and practices concerning leprosy of the Limba people of Sierra Leone. It shows that this dialectally diverse ethnic group has two views of leprosy and its cause, and two varieties of stigma associated with the disease. The Limba have abandoned their traditional treatments for leprosy in response to an effective leprosy control programme, but retained their traditional world view, including its definition of illness, which holds a person seriously ill only when he has severe pain or disability. Thus, they seek treatment from the programme, but often at a relatively advanced stage of the disease. The study shows that the Limba have reinterpreted the notion of 'germs' as introduced by medical workers, and that leprosy control workers have their own misunderstandings of Limba beliefs and practices. The study points the way to improved communication between leprosy workers and Limba patients by focusing on the points at which their views differ, and by identifying concepts within Limba world view that can be adapted by leprosy workers to help convey their message. The study emphasizes the importance of world view as a key to understanding patient attitudes and behaviour in developing countries, and to making valid cross-cultural comparisons, but notes that it can take years for an investigator to understand the world view of a particular culture. It argues that in short-term research projects there is an advantage to working with an anthropologist who has in-depth knowledge of the culture, but who may not be a specialist in medical anthropology.

Anthropology, Cultural↗
PubMed1996

Disease ecology at a crossroads: man-made environments, human rights and perpetual development utopias.

There is a growing body of critical literature on health, development and environmental sustainability in a world of finite resources and overburdened ecosystems. The ethics of progress and perpetual development in pursuit of unlimited economic growth and ever-expanding markets are no longer viable, given the constraints imposed on the life-support systems of the biosphere and a finite resource base, which poses the most serious threat to life on Earth. Despite increasing evidence of the linkages between economic growth and environmental deterioration and a rhetoric expressed in a growing body of laws, regulations, accords and global "agendas" at the national and international level, there are all too few success stories in reversing or even slowing down the current trends of ecosystem degradation and decreasing cultural and biological diversity. On the contrary, there is evidence that environmental stress and deterioration are increasing, and the impact on the mental, physical and social health and well-being of populations is more significant now than in any previous time in history. The fragmentation of countries, the rise of nationalism and ethnic conflict, the decimation of indigenous nations and human rights abuses are often closely interrelated with environmental degradation and development initiatives. This paper reviews some of the concepts and underlying values of the main "models" developed by health and social scientists for interpreting this reality, with the aim of stimulating debate that could lead to the adoption of a larger and more comprehensive framework for analysing the interactions between human health, development and environmental change.

Cultural Evolution↗
PubMed1990

The evolutionary watershed of susceptibility to gonococcal infection.

Gonococci do not cause genital infection in any convenient experimental animal, but all too easily cause genital infection in humans. To determine the 'evolutionary watershed' of gonococcal infections (the point on the evolutionary tree at which susceptibility to gonococcal infection begins) we extended previous studies of the interaction of gonococci with animal oviduct mucosa to include chimpanzees and baboons. Gonococci attached to, damaged, and invaded the oviduct (fallopian tube) mucosa of chimpanzees (which are apes) but not the oviduct mucosa of baboons (which are monkeys). Thus, the pattern of gonococcal infection in chimpanzees was identical to that in humans, whereas the pattern in baboons was like that in other animals. These studies indicate that the point in evolution at which susceptibility to gonococcal infection commences is between baboons and chimpanzees (or between monkeys and apes). Susceptibility to gonococcal disease appears to require the presence on genital epithelial cells of receptors for gonococcal ligands such as pili, receptors for gonococcal lipopolysaccharide, or both. The physiological role of these receptors may be to interact with more useful, as yet unidentified molecules.

Animals↗
PubMed2004

Investigation of G protein-initiated, Ca2+-dependent release of ATP from endothelial cells.

We investigated G protein-stimulated release of ATP from human umbilical vein endothelial cells (HUVECs) using the G protein stimulant compound 48/80. Application of compound 48/80 resulted in dose-dependent ATP evolution from cultured HUVECs. This release was not cytotoxic as demonstrated by a lactate dehydrogenase assay and the ability of the cells to load and retain the viability dye calcein following stimulation. Mastoparan also stimulated release of ATP, further suggesting the process was G-protein initiated. This G protein was insensitive to pertussis toxin and appeared to be of the Gq-subtype. The ATP efflux was completely abolished in the presence of EGTA and thapsigargin signifying a strict Ca2+ dependence. Furthermore, compound 48/80-induced release was significantly decreased in cells pretreated with the phospholipase C inhibitor U73122. Thus, the release pathway appears to proceed through an increase in intracellular Ca2+ via PLC activation. Additionally, the G protein-initiated release was attenuated by pretreatment of the cells with either phorbol ester or indolactam V, both activators of protein kinase C. Finally, ATP release was not affected by treating HUVECs with nitric oxide synthase (NOS) inhibitors or glybenclamide.

Adenosine Triphosphate↗
PubMed2006

Feasibility of hydrogen production in thermophilic mixed fermentation by natural anaerobes.

The biological sludge from an animal wastewater treatment plant was treated to enrich hydrogen-producing mixed bacteria, and effects on hydrogen yield were investigated during anaerobic fermentation at 55 degrees C. Enrichment of hydrogen-producing bacteria was conducted at pH adjustment of inocula to 3 and 5 with and without additional heat treatment (NHT and HT). The enriched mixed bacteria were cultivated at initial pHs of 5, 6, and 7 with synthetic organic wastewater containing different levels of nitrogen (2.0 and 0.8 g/l as total nitrogen) under static batch conditions. The main effects of heat treatment and enrichment pH were significant on hydrogen production. There was no significant effect of different nitrogen concentrations on hydrogen production. The methane-free biogas contained hydrogen levels of up to 64% for a fermentative condition that showed maximum hydrogen evolution (at culture pH 5 after enrichment at pH 5 with HT). The dominating intermediate metabolites were acetate, n-butyrate, and ethanol. Yields of produced hydrogen were significantly dependent upon levels of n-butyrate.

Acetates↗
PubMed2005

Strategic mating with common preferences.

We present a two-sided search model in which individuals from two groups (males and females, employers and workers) would like to form a long-term relationship with a highly ranked individual of the other group, but are limited to individuals who they randomly encounter and to those who also accept them. This article extends the research program, begun in Alpern and Reyniers [1999. J. Theor. Biol. 198, 71-88], of providing a game theoretic analysis for the Kalick-Hamilton [1986. J. Personality Soc. Psychol. 51, 673-682] mating model in which a cohort of males and females of various 'fitness' or 'attractiveness' levels are randomly paired in successive periods and mate if they accept each other. Their model compared two acceptance rules chosen to represent homotypic (similarity) preferences and common (or 'type') preferences. Our earlier paper modeled the first kind by assuming that if a level x male mates with a level y female, both get utility -|x-y|, whereas this paper models the second kind by giving the male utility y and the female utility x. Our model can also be seen as a continuous generalization of the discrete fitness-level game of Johnstone [1997. Behav. Ecol. Sociobiol. 40, 51-59]. We establish the existence of equilibrium strategy pairs, give examples of multiple equilibria, and conditions guaranteeing uniqueness. In all equilibria individuals become less choosy over time, with high fitness individuals pairing off with each other first, leaving the rest to pair off later. This route to assortative mating was suggested by Parker [1983. Mate Choice, Cambridge University Press, Cambridge, pp. 141-164]. If the initial fitness distributions have atoms, then mixed strategy equilibria may also occur. If these distributions are unknown, there are equilibria in which only individuals in the same fitness band are mated, as in the steady-state model of MacNamara and Collins [1990. J. Appl. Prob. 28, 815-827] for the job search problem.

Animals↗