368 research outputs found

    Investigating Life History Differences Between Finetooth Sharks, Carcharhinus isodon, in the Northern Gulf of Mexico and the Western North Atlantic Ocean

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    The life history of the finetooth shark, Carcharhinus isodon, off South Carolina was studied by determining age, growth, and size and age at maturity. These data were compared to a recent study describing the same parameters for finetooth sharks in the northern Gulf of Mexico. Cervical vertebrae were extracted from 168 specimens (71 males and 97 females), ranging in size from 376 to 1,262 mm fork length (FL), and prepared for age analysis using standard techniques. Sex-specific von Bertalanffy growth models were generated and yielded the following growth equations: Lt = 1,311 mm FL (1 - e-0.19(t - (-2.17))) for females and Lt = 1,151 mm FL (1 - e-0.33(t - (-1.43))) for males. The oldest female and male aged were 12.4 yr and 10.4 yr, respectively. Median length where 50% of the population was mature was 1,021 mm FL for females, corresponding to an age of 6.3 yr and 1,015 mm FL for males, corresponding to an age of 5.0 yr. Finetooth sharks in the western North Atlantic Ocean had higher observed ages and there was a significant difference in size at age between neonate finetooth sharks in the western North Atlantic Ocean and the northern Gulf of Mexico; however, there were no significant differences among von Bertalanffy growth function parameters between regions examined. Results indicate lower amounts of regional variation in life history parameters for finetooth sharks when compared to other small coastal sharks

    Metabolic flexibility as a major predictor of spatial distribution in microbial communities

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    A better understand the ecology of microbes and their role in the global ecosystem could be achieved if traditional ecological theories can be applied to microbes. In ecology organisms are defined as specialists or generalists according to the breadth of their niche. Spatial distribution is often used as a proxy measure of niche breadth; generalists have broad niches and a wide spatial distribution and specialists a narrow niche and spatial distribution. Previous studies suggest that microbial distribution patterns are contrary to this idea; a microbial generalist genus (Desulfobulbus) has a limited spatial distribution while a specialist genus (Methanosaeta) has a cosmopolitan distribution. Therefore, we hypothesise that this counter-intuitive distribution within generalist and specialist microbial genera is a common microbial characteristic. Using molecular fingerprinting the distribution of four microbial genera, two generalists, Desulfobulbus and the methanogenic archaea Methanosarcina, and two specialists, Methanosaeta and the sulfate-reducing bacteria Desulfobacter were analysed in sediment samples from along a UK estuary. Detected genotypes of both generalist genera showed a distinct spatial distribution, significantly correlated with geographic distance between sites. Genotypes of both specialist genera showed no significant differential spatial distribution. These data support the hypothesis that the spatial distribution of specialist and generalist microbes does not match that seen with specialist and generalist large organisms. It may be that generalist microbes, while having a wider potential niche, are constrained, possibly by intrageneric competition, to exploit only a small part of that potential niche while specialists, with far fewer constraints to their niche, are more capable of filling their potential niche more effectively, perhaps by avoiding intrageneric competition. We suggest that these counter-intuitive distribution patterns may be a common feature of microbes in general and represent a distinct microbial principle in ecology, which is a real challenge if we are to develop a truly inclusive ecology

    Conceiving time?: women who do or do not conceive

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    This article explores the importance of time for an understanding of women's experiences of reproductive identity. In order to do this we draw on data from two separate qualitative research projects. The first project is concerned with the experiences of conception, pregnancy, childbirth and early motherhood in primagravidae, whilst the second focuses on the experiences of individuals (especially women) who defined themselves (at the time of the fieldwork, or some time previously) as 'involuntarily childless' and/or 'infertile'. These two areas are usually treated as separate; however this article explores similarities between them in terms of time and medicalisation. Our central concern then is with exploring the similarities of experience for women who do or do not conceive

    The rate and locus of development of rat vallate taste buds

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    Several hundred taste buds develop and mature in the trench walls of the rat's vallate papilla during the first 3 months after birth. The objective of this investigation of taste bud development was to determine: (i) whether the vallate papilla has local growth zones where new taste buds form, (ii) whether new taste buds arise by the division of mature taste buds, (iii) how many days are required for a new taste bud to mature, and (iv) whether a taste pore forms as the taste bud reaches a critical volume. Camera lucida drawings were made of more than 4000 iron hematoxylin-stained, serially sectioned, vallate taste buds. The relative abundance of immature taste buds declined exponentially with age, from 18% of the mature taste buds at day 15 to 2% at day 90. At days 21, 33 and 45 most of the immature taste buds (those lacking a taste pore) were located in growth zones at the anterior and posterior extremes of the vallate trench. A mean of 10.5 days was required for the maturation of each cohort of immature taste buds present at days 15, 21, 33 and 45. Vallate taste buds were added de novo; fission of mature taste buds was rare. Taste buds varied widely in the taste bud volume at which a pore formed and in the final volume of the taste bud.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29449/1/0000531.pd

    Sensorimotor Inhibition and Mobility in Genetic Subgroups of Parkinson's Disease

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    Background: Mobility and sensorimotor inhibition impairments are heterogeneous in Parkinson's disease (PD). Genetics may contribute to this heterogeneity since the apolipoprotein (APOE) ε4 allele and glucocerebrosidase (GBA) gene variants have been related to mobility impairments in otherwise healthy older adult (OA) and PD cohorts. The purpose of this study is to determine if APOE or GBA genetic status affects sensorimotor inhibition and whether the relationship between sensorimotor inhibition and mobility differs in genetic sub-groups of PD. Methods: Ninety-three participants with idiopathic PD (53 non-carriers; 23 ε4 carriers; 17 GBA variants) and 72 OA (45 non-carriers; 27 ε4 carriers) had sensorimotor inhibition characterized by short-latency afferent inhibition. Mobility was assessed in four gait domains (pace/turning, rhythm, trunk, variability) and two postural sway domains (area/jerkiness and velocity) using inertial sensors. Results: Sensorimotor inhibition was worse in the PD than OA group, with no effect of genetic status. Gait pace/turning was slower and variability was higher (p < 0.01) in PD compared to OA. Postural sway area/jerkiness (p < 0.01) and velocity (p < 0.01) were also worse in the PD than OA group. Genetic status was not significantly related to any gait or postural sway domain. Sensorimotor inhibition was significantly correlated with gait variability (r = 0.27; p = 0.02) and trunk movement (r = 0.23; p = 0.045) in the PD group. In PD non-carriers, sensorimotor inhibition related to variability (r = 0.35; p = 0.010) and trunk movement (r = 0.31; p = 0.025). In the PD ε4 group, sensorimotor inhibition only related to rhythm (r = 0.47; p = 0.024), while sensorimotor inhibition related to pace/turning (r = -0.49; p = 0.046) and rhythm (r = 0.59; p = 0.013) in the PD GBA group. Sensorimotor inhibition was significantly correlated with gait pace/turning (r = -0.27; p = 0.04) in the OA group. There was no relationship between sensorimotor inhibition and postural sway. Conclusion: ε4 and GBA genetic status did not affect sensorimotor inhibition or mobility impairments in this PD cohort. However, worse sensorimotor inhibition was associated with gait variability in PD non-carriers, but with gait rhythm in PD ε4 carriers and with gait rhythm and pace in PD with GBA variants. Impaired sensorimotor inhibition had a larger effect on mobility in people with PD than OA and affected different domains of mobility depending on genetic status

    Managing and monitoring equality and diversity in UK sport: An evaluation of the sporting equals Racial Equality Standard and its impact on organizational change

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    Despite greater attention to racial equality in sport in recent years, the progress of national sports organizations toward creating equality of outcomes has been limited in the United Kingdom. The collaboration of the national sports agencies, equity organizations and national sports organizations (including national governing bodies of sport) has focused on Equality Standards. The authors revisit an earlier impact study of the Racial Equality Standard in sport and supplement it with another round of interview material to assess changing strategies to manage diversity in British sport. In particular, it tracks the impact on organizational commitment to diversity through the period of the establishment of the Racial Equality Standard and its replacement by an Equality Standard that deals with other diversity issues alongside race and ethnicity. As a result, the authors question whether the new, generic Equality Standard is capable of addressing racial diversity and promoting equality of outcomes. © 2006 Sage Publications

    Prime beef cuts : culinary images for thinking 'men'

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    The paper contributes to scholarship theorising the sociality of the brand in terms of subject positions it makes possible through drawing upon the generative context of circulating discourses, in this case of masculinity, cuisine and celebrity. Specifically, it discusses masculinity as a socially constructed gender practice (Bristor and Fischer, 1993), examining materialisations of such practice in the form of visualisations of social relations as resources for 'thinking gender' or 'doing gender'. The transformative potential of the visualisations is illuminated by exploring the narrative content choreographed within a series of photographic images positioning the market appeal of a celebrity chef through the medium of a contemporary lifestyle cookery book. We consider how images of men 'doing masculinity'are not only channelled into reproducing existing gender hierarchy and compulsory heterosexuality in the service of commercial ends, but also into disrupting such enduring stereotyping through subtle reframing. We acknowledge that masculinity is already inscribed within conventionalised representations of culinary culture. In this case we consider how traces of masculinity are exploited and reinscribed through contemporary images that generate resources for rethinking masculine roles and identities, especially when viewed through the lens of stereotypically feminised pursuits such as shopping, food preparation, cooking, and the communal intimacy of food sharing. We identify unsettling tensions within the compositions, arguing that they relate to discursive spaces between the gendered positions written into the images and the popular imagination they feed off. Set against landscapes of culinary culture, we argue that the images invoke a brand of naively roughish "laddishness" or "blokishness", rendering it in domesticated form not only as benign and containable, but fashionable, pliable and, importantly, desirable. We conclude that although the images draw on stereotypical premeditated notions of a feral, boisterous and untamed heterosexual masculinity, they also set in motion gender-blending narratives

    “It's like giving him a piece of me.”: Exploring UK and Israeli women's accounts of motherhood and feeding

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    Objective The present study explored how Israeli and UK mothers integrate feeding into their conceptualisations of mothering 2–6 months post-partum. Background The nature and importance of motherhood is subject to differential contextual, cultural, political and historical influences. We set out to compare experiences of motherhood and feeding between these two countries using a qualitative approach. Methods Forty one women (mean age 36.4 ± 2.7 years) from Israel and the UK, mostly married or in a committed relationship were interviewed about their experience of pregnancy, motherhood and feeding. Data were analysed thematically. Results The experience of motherhood in the early postnatal period was dominated, for all mothers, by the experience of breastfeeding and clustered around three representations of mothering, namely; 1) a devoted mother who ignores her own needs; 2) a mother who is available for her infant but acknowledges her needs as well; and 3) a struggling mother for whom motherhood is a burden. Such representations existed within both cultural groups and sometimes coexisted within the same mothers. UK women described more struggles within motherhood whereas a tendency towards idealising motherhood was observed for Israeli women. Conclusion There are similarities in the ways that UK and Israeli women experienced motherhood and feeding. Where family life is strongly emphasized, mothers reported extremes of idealism and burden and associated an “ideal” mother with a breastfeeding mother. Where motherhood is represented as just one of many roles women take up, they are more likely to represent a “good enough” approach to mothering. Understanding the experience of motherhood and feeding in different cultural settings is important to provide the context for postnatal care specifically where mothers are reluctant to share problems or difficulties encountered
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