652 research outputs found

    A population biology of breeding redshanks (Tringa totanus L.)

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    A breeding population of Redshanks was studied by trapping adults at the nest and individually marking them, over a period of nine years, on part of the extensive Ribble saltmarshes. Other aspects of breeding biology were investigated over three years. The capture-recapture analysis of the breeding adults revealed an overall annual survival rate, of both sexes, of 0.77, and a population of approximately 200 pairs in 1.04km? Mate fidelity was very high, with 71% of surviving pairs remaining faithful. Nest site fidelity was extremely strong for faithful pairs and males with new mates, but significantly weaker for females with new mates. A lower nest site fidelity of young birds was regarded as a major contributing factor to their lower recapture rates. The timing of both the onset and ending of the breeding seasons varied greatly, and was determined mainly by the rainfall. High rainfall delayed onset and hastened ending of breeding. Mithin a breeding season the older birds bred throughout, while the young ones were mostly not able to breed early. The substantial losses of nests due to cattle grazing on the marsh (45%) could easily be controlled by preventing the access of cattle to the main breeding area until after the end of the nesting season. Nest predation was rare (less than 4%) in most years, but increased in a year of short vegetation (to 25%). The production of pulli was estimated under varying environmental influences and ranged from 0.73 to 2.28 pulli. pair": The variation of egg size within the population was investigated and the significant influences of laying order (within a clutch) and maternal size demonstrated. Pullus size at hatching was positively correlated with egg size and also with maternal size. The growth and development of pulli were described for weight, bill length, tarsus length and postnatal moult. For three days after hatching the weight remained below the hatching value and then rapidly increased, whereas the bill and tarsus showed a linear increase in length A tentative model of the population dynamics was produced, despite the lack of good estimates of pre- and post-fledging mortality. This model indicated a high pre-fledging mortality of 0.67 and also further highlighted the impact on the population of cattle grazing during the nesting season

    Sensation of presence and cybersickness in applications of virtual reality for advanced rehabilitation

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    Around three years ago, in the special issue on augmented and virtual reality in rehabilitation, the topics of simulator sickness was briefly discussed in relation to vestibular rehabilitation. Simulator sickness with virtual reality applications have also been referred to as visually induced motion sickness or cybersickness. Recently, study on cybersickness has been reported in entertainment, training, game, and medical environment in several journals. Virtual stimuli can enlarge sensation of presence, but they sometimes also evoke unpleasant sensation. In order to safely apply augmented and virtual reality for long-term rehabilitation treatment, sensation of presence and cybersickness should be appropriately controlled. This issue presents the results of five studies conducted to evaluate visually-induced effects and speculate influences of virtual rehabilitation. In particular, the influence of visual and vestibular stimuli on cardiovascular responses are reported in terms of academic contribution

    Positive and negative evaluation of caregiving among three different types of informal care relationships

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    Based on the caregiver stress model, we examined how care demands, caregiver motivation, coping style and external support are associated with positive evaluation and caregiver burden among spousal, adult child and other types of care relations. Data from a sample of Dutch informal caregivers of 1,685 older persons (55 and older) were analyzed employing multivariate linear regression analyses for each of the care relationship types. Spouses (N = 206) report high positive evaluation and high burden, adult children (N = 1,093) report low positive evaluation, and other caregivers (N = 386) report high positive evaluation and a low burden. Multivariate linear regression analyses showed that motives and external support were important for positive evaluation but the impact varied among types of caregivers, whereas care demands and not asking for help were associated with burden for all types. Only among 'other' caregiver relationships, positive evaluation was negatively associated with burden. It is concluded that results confirm the dual nature of caregiving among spouses and children. The care context and motivation of the different types of caregivers explain their differences in care evaluation. Various interventions for types of caregivers are discussed. © 2013 Springer-Verlag Berlin Heidelberg

    Exploring Protein-Protein Interactions as Drug Targets for Anti-cancer Therapy with In Silico Workflows

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    We describe a computational protocol to aid the design of small molecule and peptide drugs that target protein-protein interactions, particularly for anti-cancer therapy. To achieve this goal, we explore multiple strategies, including finding binding hot spots, incorporating chemical similarity and bioactivity data, and sampling similar binding sites from homologous protein complexes. We demonstrate how to combine existing interdisciplinary resources with examples of semi-automated workflows. Finally, we discuss several major problems, including the occurrence of drug-resistant mutations, drug promiscuity, and the design of dual-effect inhibitors.Fil: Goncearenco, Alexander. National Institutes of Health; Estados UnidosFil: Li, Minghui. Soochow University; China. National Institutes of Health; Estados UnidosFil: Simonetti, Franco Lucio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Shoemaker, Benjamin A. National Institutes of Health; Estados UnidosFil: Panchenko, Anna R. National Institutes of Health; Estados Unido

    The role of complement in ocular pathology

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    Functionally active complement system and complement regulatory proteins are present in the normal human and rodent eye. Complement activation and its regulation by ocular complement regulatory proteins contribute to the pathology of various ocular diseases including keratitis, uveitis and age-related macular degeneration. Furthermore, a strong relationship between age-related macular degeneration and polymorphism in the genes of certain complement components/complement regulatory proteins is now well established. Recombinant forms of the naturally occurring complement regulatory proteins have been exploited in the animal models for treatment of these ocular diseases. It is hoped that in the future recombinant complement regulatory proteins will be used as novel therapeutic agents in the clinic for the treatment of keratitis, uveitis, and age-related macular degeneration

    Troppo - A Python framework for the reconstruction of context-specific metabolic models

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    The surge in high-throughput technology availability for molecular biology has enabled the development of powerful predictive tools for use in many applications, including (but not limited to) the diagnosis and treatment of human diseases such as cancer. Genome-scale metabolic models have shown some promise in clearing a path towards precise and personalized medicine, although some challenges still persist. The integration of omics data and subsequent creation of context-specific models for specific cells/tissues still poses a significant hurdle, and most current tools for this purpose have been implemented using proprietary software. Here, we present a new software tool developed in Python, troppo - Tissue-specific RecOnstruction and Phenotype Prediction using Omics data, implementing a large variety of context-specific reconstruction algorithms. Our framework and workflow are modular, which facilitates the development of newer algorithms or omics data sources.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. The authors also thank the PhD scholarships funded by national funds through Fundacao para a Ciencia e Tecnologia, with references: SFRH/BD/133248/2017 (J.F.), SFRH/BD/118657/2016 (V.V.).info:eu-repo/semantics/publishedVersio

    Imaging in breast cancer: Diffuse optics in breast cancer: detecting tumors in pre-menopausal women and monitoring neoadjuvant chemotherapy

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    Diffuse optical spectroscopy (DOS) and diffuse optical imaging (DOI) are non-invasive diagnostic techniques that employ near-infrared (NIR) light to quantitatively characterize the optical properties of centimeter-thick, multiple-scattering tissues. Although NIR was first applied to breast diaphanography more than 70 years ago, quantitative optical methods employing time- or frequency-domain 'photon migration' technologies have only recently been used for breast imaging. Because their performance is not limited by mammographic density, optical methods can provide new insight regarding tissue functional changes associated with the appearance, progression, and treatment of breast cancer, particularly for younger women and high-risk subjects who may not benefit from conventional imaging methods. This paper reviews the principles of diffuse optics and describes the development of broadband DOS for quantitatively measuring the optical and physiological properties of thick tissues. Clinical results are shown highlighting the sensitivity of diffuse optics to malignant breast tumors in 12 pre-menopausal subjects ranging in age from 30 to 39 years and a patient undergoing neoadjuvant chemotherapy for locally advanced breast cancer. Significant contrast was observed between normal and tumor regions of tissue for deoxy-hemoglobin (p = 0.005), oxy-hemoglobin (p = 0.002), water (p = 0.014), and lipids (p = 0.0003). Tissue hemoglobin saturation was not found to be a reliable parameter for distinguishing between tumor and normal tissues. Optical data were converted into a tissue optical index that decreased 50% within 1 week in response to neoadjuvant chemotherapy. These results suggest a potential role for diffuse optics as a bedside monitoring tool that could aid the development of new strategies for individualized patient care
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