82 research outputs found

    Reproduction in the protogynous black grouper Mexico (Mycteroperca bonaci (Poey)) from the southern Gulf of Mexico

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    An analysis was made of sexual pattern, spawning season, sizes at sexual maturation, and sex change in black grouper (Mycteroperca bonaci) from the southern Gulf of Mexico. Samples were taken between 1996 and 2000, from industrial and small-craft commercial fi sheries, in offshore and inshore waters of the continental shelf of the Yucatan Peninsula (Campeche Bank), including the shallow waters of National Marine Park Alacranes Reef. For all collected specimens (n=1229), sex and maturation condition were determined by histological analysis of the gonads. The offshore sample consisted of 75.1% females, 24.3% males, and 0.6% transitional-stage fish. All individuals collected from inshore waters were females. Gonadal structure and population structure characteristics for Campeche Bank black grouper were consistent with the characteristics of monandric protogynous hermaphrodism for a serranid fish. Sexually active males and females were observed year-round, although ripening females, with stage-III, -IV, and -V vitellogenic oocytes in the ovaries, dominated in samples taken between December and March. In addition, peak occurrence of ripe-running females with hyaline oocytes or postovulatory follicles (or both) in the ovaries was recorded in January and February. A few precocious females began spawning in October and November, and others were still in spawning condition in May and June. Fifty percent maturity of females was attained at 72.1 cm fork length (FL). Median size at sexual inversion was 103.3 cm FL, and 50% of the females measuring 111.4 cm FL had transformed into males. The southern Gulf of Mexico grouper fishery was considered deteriorated and lacked a well-defined management strategy. Results of the present study provide helpful information on black grouper reproduction in this area and could help Mexican authorities choose appropriate management strategies for this fishery, such as minimum size limit, closed fishing season, and protection of spawning aggregations

    What we learn when designing with marginalised children

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    Designing with marginalised children often produces detailed insights about their lives and communities. Whilst it is possible to extract methodological and artefact-centred knowledge from existing design cases, it can be difficult to utilise and build on some of the more complex and multifaceted issues that these generate, for instance, how researcher decisions inform design outcomes. In this workshop, we invite researchers to reflect on the insights design case studies with marginalized children offer to the larger Children-Computer Interaction (CCI) community. Our goals are to reflect on what kinds of insights are generated; what we as design researchers and practitioners would have wanted to know prior to undertaking such work, and; to identify ways of communicating these insights

    Evolution of PEKK crystallization measured in laser sintering

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    This is the final version. Available on open access from Frontiers Media via the DOI in this recordData availability statement: The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author.The rising popularity of laser sintering (LS) technology has increased by the broadening of available materials for this process. Kepstan 6002 poly (ether ketone ketone) (PEKK) was recently launched as a high-performance polymer grade with a lower processing temperature and unique crystallization kinetics. This study aims to understand the progress of crystallization on samples manufactured throughout the laser sintering process. These results were compared with isothermal and dynamic differential scanning calorimetry (DSC) experiments with different cooling rates. Kepstan 6002 PEKK processed by high-temperature laser sintering (HT-LS) presents a kinetics of crystallization in the order of ∼10 times slower than its crystallized samples in the DSC. This result highlights the need for a part-based crystallization investigation rather than isothermal models to describe the crystallization in LS. The transmission electron microscopy (TEM) analysis reveals smaller spherulites in the samples subjected to prolonged cooling times and an almost amorphous structure for the PEKK samples exposed to almost no cooling. This experiment identified the surroundings of laser sintered particles as preferential sites for crystallization initiation, which grows as the particles penetrate the molten layers and spherulites are formed. The slower kinetics of crystallization of Kepstan 6002 PEKK grade improve the adhesion between layers in laser sintering and enable tailoring its properties according to the application. Understanding the relationship between intrinsic material characteristics and the resulting final properties is vital to optimizing the process and controlling the final performance of PEKK for different applications.University of ExeterArkema Chemistry Co

    Simulation directe 2D et 3D de la dispersion d'agglomérats sous cisaillement dans une matrice polymère

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    Nous avons développé une méthode de simulation directe de la dispersion de charges sphériques dans une matrice polymère soumise à un cisaillement. L'agglomérat est immergé dans un fluide newtonien et incompressible. Il est considéré comme un assemblage de sphères liées entre elles par une énergie de cohésion, modélisée par une viscosité de cohésion. Les paramètres de ce modèle sont la contrainte hydrodynamique et la longueur caractéristique de la zone d'influence des sphères. Ce modèle simple permet une première approche du phénomène de dispersion dans un écoulement de cisaillement. Les tendances observées lors des simulations menées en 2D et 3D montrent qu'une augmentation du taux de cisaillement entraîne une érosion plus rapide de la charge

    Human-Computer Interaction and the Future ofWork

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    Advances in computing technology, changing policies, and slow crises are rapidly changing the way we work. Human-computer interaction (HCI) is a critical aspect of these trends, to understand how workers contend with emerging technologies and how design might support workers and their values and aspirations amidst technological change. This SIG invites HCI researchers across diverse domains to reflect on the range of approaches to future of work research, recognize connections and gaps, and consider how HCI can support workers and their wellbeing in the future

    Functional outcomes in adult patients with herpes simplex encephalitis admitted to the ICU: a multicenter cohort study

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    PURPOSE: We aimed to study the association of body temperature and other admission factors with outcomes of herpes simplex encephalitis (HSE) adult patients requiring ICU admission. METHODS: We conducted a retrospective multicenter study on patients diagnosed with HSE in 47 ICUs in France, between 2007 and 2017. Fever was defined as a body temperature higher or equal to 38.3 °C. Multivariate logistic regression analysis was used to identify factors associated with poor outcome at 90 days, defined by a score of 3-6 (indicating moderate-to-severe disability or death) on the modified Rankin scale. RESULTS: Overall, 259 patients with a score on the Glasgow coma scale of 9 (6-12) and a body temperature of 38.7 (38.1-39.2) °C at admission were studied. At 90 days, 185 (71%) patients had a poor outcome, including 44 (17%) deaths. After adjusting for age, fever (OR = 2.21; 95% CI 1.18-4.16), mechanical ventilation (OR = 2.21; 95% CI 1.21-4.03), and MRI brain lesions > 3 lobes (OR = 3.04; 95% CI 1.35-6.81) were independently associated with poor outcome. By contrast, a direct ICU admission, as compared to initial admission to the hospital wards (i.e., indirect ICU admission), was protective (OR = 0.52; 95% CI 0.28-0.95). Sensitivity analyses performed after adjustment for functional status before admission and reason for ICU admission yielded similar results. CONCLUSIONS: In HSE adult patients requiring ICU admission, several admission factors are associated with an increased risk of poor functional outcome. The identification of potentially modifiable factors, namely, elevated admission body temperature and indirect ICU admission, provides an opportunity for testing further intervention strategies

    Measures of happiness: Which to choose?

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    Happiness is defined as the subjective enjoyment of one’s life as a whole, also called ‘life-satisfaction.’ Two components of happiness are distinguished; an affective component (how well one feels most of the time) and a cognitive component (the degree to which one perceived to get what one wants from life). In this chapter, I present an overview of valid measures of these concepts, drawing on the ‘Collection of Happiness Measures’ of the ‘World Database of Happiness’. To date (2016), this collection includes more than twothousand measures of happiness, mostly single direct questions. Links in this text lead to detail about these measures and the studies in this chapter, I describe the differences and discuss their strengths and weaknesse
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