444 research outputs found

    Toward a consensus nomenclature for ghrelin, its non-acylated form, liver expressed antimicrobial peptide 2 and growth hormone secretagogue receptor

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    The stomach-derived octanoylated peptide ghrelin was discovered in 1999 and recognized as an endogenous agonist of the growth hormone secretagogue receptor (GHSR). Subsequently, ghrelin has been shown to play key roles in controlling not only growth hormone secretion, but also a variety of other physiological functions including, but not limited to, food intake, reward-related behaviors, glucose homeostasis and gastrointestinal tract motility. Importantly, a non-acylated form of ghrelin, desacyl-ghrelin, can also be detected in biological samples. Desacyl-ghrelin, however, does not bind to GHSR at physiological levels, and its physiological role has remained less well-characterized than that of ghrelin. Ghrelin and desacyl-ghrelin are currently referred to in the literature using many different terms, highlighting the need for a consistent nomenclature. The variability of terms used to designate ghrelin can lead not only to confusion, but also to miscommunication, especially for those who are less familiar with the ghrelin literature. Thus, we conducted a survey among experts who have contributed to the ghrelin literature aiming to identify whether a consensus may be reached. Based on the results of this consensus, we propose using the terms “ghrelin” and “desacyl-ghrelin” to refer to the hormone itself and its non-acylated form, respectively. Based on the results of this consensus, we further propose using the terms “GHSR” for the receptor, and “LEAP2” for liver-expressed antimicrobial peptide 2, a recently recognized endogenous GHSR antagonist/inverse agonist.Fil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Dickson, Suzanne L.. The Sahlgrenska Academy at the University of Gothenburg; SueciaFil: Zigman, Jeffrey M.. UT Southwestern Medical Center; Estados UnidosFil: Leggio, Lorenzo. National Institutes of Health; Estados Unido

    Background Check:A General Technique to Build More Reliable and Versatile Classifiers

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    Differences in the financial approach to entrepreneurship from a gender perspective

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    [EN] The economic situation worldwide has led to a global rise in female entrepreneurship. Furthermore, entrepreneurial activity has become very important and is considered fundamental to adopt measures that encourage and correct deficiencies. To this end, the purpose of this work is to study the financing of this venture from a gender perspective by taking a sample of entrepreneurs from a Spanish Mediterranean region. We analysed factors of capital structure, company ownership and funding sources (formal and informal), among other aspects, with a sample of 192 surveyed entrepreneurs. By multivariate analysis techniques, the statistically significant differences that appeared between male and female entrepreneurs were studied. This study is important and might be useful because it provides an overview of the current situation of entrepreneurs and funding sources in not only the studied Mediterranean region, but also in similar Mediterranean and/or Spanish regions.This work has been funded by the R+D project for emerging research groups with reference (GVA) GV/2016/078.Cervelló Royo, RE.; Moya Clemente, I.; Perello-Marin, MR.; Ribes-Giner, G. (2021). Differences in the financial approach to entrepreneurship from a gender perspective. International Journal of Globalisation and Small Business. 12(1):46-58. https://doi.org/10.1504/IJGSB.2021.113817465812

    Physiological Measures of Risk Perception in Highly Automated Driving

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    Highly automated driving will likely result in drivers being out-of-the-loop during specific scenarios and engaging in a wide range of non-driving related tasks. Manifesting in lower levels of risk perception to emerging events, and thus affect drivers' availability to take-over manual control in safety-critical scenarios. In this empirical research, we measured drivers' (N = 20) risk perception with cardiac and skin conductance indicators through a series of high-fidelity, simulated highly automated driving scenarios. By manipulating the presence of surrounding traffic and changing driving conditions as long-term risk modulators, and including a driving hazard event as a short-term risk modulator, we hypothesised that an increase in risk perception would induce greater physiological arousal. Our results demonstrate that heart rate variability features are superior at capturing arousal variations from these long-term, low to moderate risk scenarios. In contrast, skin conductance responses are more sensitive to rapidly evolving situations associated with moderate to high risk. Based on this research, future driver state monitoring systems should adopt multiple physiological measures to capture changes in the long and short term, modulation of risk perception. This will enable enhanced perception of driver readiness and improved availability to safely deal with take-over events when requested by an automated vehicle.</p

    Effects of Local Weather Variation on Water-column Stratification and Hypoxia in the Western, Sandusky, and Central Basins of Lake Erie

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    Hypoxia, low dissolved oxygen (DO) concentrations (<2 mg/L), has been a major issue in Lake Erie for decades. While much emphasis has been placed on biological factors, particularly algal blooms, contributing to hypolimnetic oxygen depletion, there has been little focus on the role of weather. For this study, we monitored water temperature and DO concentrations at sites in the western, central, and Sandusky basins in Lake Erie during June and July 2010–2012. We then compared trends in stratification and DO concentrations to weather patterns during that period. We found that during those three years, there was significant variation in weather patterns, particularly decreased ice coverage and increased storm events in 2012. These weather patterns corresponded to 2012 having the warmest water temperatures, some of the lowest DO concentrations, and a deeper and thinner hypolimnion (especially in the central basin) than the previous years. We found a relationship between weather and hypoxia, providing further evidence for why these basins are susceptible to low DO conditions during summer months. The role of weather in hypoxia is another indication that the lake is vulnerable to effects of climate change and should be considered in management strategies

    Wavelet multiscale analysis for hedge funds: scaling and strategies

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    The wide acceptance of Hedge Funds by Institutional Investors and Pension Funds has led to an explosive growth in assets under management. These investors are drawn to Hedge Funds due to the seemingly low correlation with traditional investments and the attractive returns. The correlations and market risk (the Beta in the Capital Asset Pricing Model) of Hedge Funds are generally calculated using monthly returns data, which may produce misleading results as Hedge Funds often hold illiquid exchange-traded securities or difficult to price over-the- counter securities. In this paper, the Maximum Overlap Discrete Wavelet Transform (MODWT) is applied to measure the scaling properties of Hedge Fund correlation and market risk with respect to the S&P 500. It is found that the level of correlation and market risk varies greatly according to the strategy studied and the time scale examined. Finally, the effects of scaling properties on the risk profile of a portfolio made up of Hedge Funds is studied using correlation matrices calculated over different time horizons

    Ghrelin Indirectly Activates Hypophysiotropic CRF Neurons in Rodents

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    Ghrelin is a stomach-derived hormone that regulates food intake and neuroendocrine function by acting on its receptor, GHSR (Growth Hormone Secretagogue Receptor). Recent evidence indicates that a key function of ghrelin is to signal stress to the brain. It has been suggested that one of the potential stress-related ghrelin targets is the CRF (Corticotropin-Releasing Factor)-producing neurons of the hypothalamic paraventricular nucleus, which secrete the CRF neuropeptide into the median eminence and activate the hypothalamic-pituitary-adrenal axis. However, the neural circuits that mediate the ghrelin-induced activation of this neuroendocrine axis are mostly uncharacterized. In the current study, we characterized in vivo the mechanism by which ghrelin activates the hypophysiotropic CRF neurons in mice. We found that peripheral or intra-cerebro-ventricular administration of ghrelin strongly activates c-fos – a marker of cellular activation – in CRF-producing neurons. Also, ghrelin activates CRF gene expression in the paraventricular nucleus of the hypothalamus and the hypothalamic-pituitary-adrenal axis at peripheral level. Ghrelin administration directly into the paraventricular nucleus of the hypothalamus also induces c-fos within the CRF-producing neurons and the hypothalamic-pituitary-adrenal axis, without any significant effect on the food intake. Interestingly, dual-label immunohistochemical analysis and ghrelin binding studies failed to show GHSR expression in CRF neurons. Thus, we conclude that ghrelin activates hypophysiotropic CRF neurons, albeit indirectly

    Analysis of patient domestic activity in recovery from hip or knee replacement surgery: modelling wrist-worn wearable RSSI and accelerometer data in the wild

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    The UK health service sees around 160,000 total hip or knee replacements every year and this number is expected to rise. Expectations of surgical outcome are changing alongside demographic trends, whilst aftercare may be fractured as a result of resource limitation or other factors. Conventional assessments of health outcomes must evolve to keep up with these changing trends. In practice, patients may visit a health care professional to discuss recovery and will provide survey feedback to clinicians using standardised instruments, such as the Oxford Hip & Knee score, in the months following surgery. To aid clinicians in providing accurate assessment of patient recovery a continuous home health care monitoring system would be beneficial. In this paper the authors explore how the SPHERE sensor network can be used to automatically generate measures of recovery from arthroplasty to facilitate continuous monitoring of behaviour, including location, room transitions, movement and activity; in terms of frequency and duration; in a domestic environment. The authors present a case study of data collected from a home equipped with the SPHERE sensor network. Machine learning algorithms are applied to a week of continuous observational data to generate insights into the domestic routine of the occupant. Testing of models shows that location and activity are classified with 86% and 63% precision, respectively

    Measurement of the Growth of the Main Commercial Rays (Raja clavata, Raja brachyura, Torpedo marmorata, Dipturus oxyrinchus) in European Waters Using Intercalibration Methods

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    The intercalibration of age readings represents a crucial step in the ageing procedure; the use of different sampling methods, structures, preparation techniques, and ageing criteria can significantly affect age and growth data. This study evaluated the precision and accuracy of ageing for the most important North Atlantic (NA) and Mediterranean (M) ray species, Raja clavata, Raja brachyura, Torpedo marmorata, and Dipturus oxyrinchus, through exchange exercises carried out by readers from different laboratories. In addition, growth parameters were estimated from the obtained data. A total of 663 individual batoids were analysed. R. clavata and R. brachyura samples were obtained from both the NA and the M, while vertebral centra of T. marmorata and D. oxyrinchus were only available for the M. High reading variability was observed for all four evaluated species in terms of CV, APE, and PA. D. oxyrinchus and T. marmorata showed relatively slow growth and the von Bertalanffy model with fixed t(0) and Gompertz's model were, respectively, the most precise models for each of these species. In R. brachyura, females had a faster growth rate compared to combined sexes. The vbt0p proved the most precise model for describing growth in this species, and no statistical differences were found between the NO and the M. For R. clavata, the best-fitting model was the vbt0p for females and males in the NO and for females from the M, while the best-fitting model for males from the M and sexes combined for both areas was log.p. Distinct growth patterns were observed between the two study areas

    Trichinellosis surveillance in wildlife in northeastern argentine patagonia

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    Fil: Winter, Marina. Universidad Nacional de Río Negro, Sede Atlántica; ArgentinaFil: Winter, Marina. Centro de Investigaciones y Transferencia Río Negro (CONICET-UNRN); ArgentinaFil: Pasqualetti, Mariana I. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Parasitología y Enfermedades Parasitarias; ArgentinaFil: Pasqualetti, Mariana I. Instituto de Investigaciones en Producción Animal (INPA); ArgentinaFil: Pasqualetti, Mariana I. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fariña, Fernando A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Parasitología y Enfermedades Parasitarias; ArgentinaFil: Fariña, Fernando A. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fariña, Fernando A. Instituto de Investigaciones en Producción Animal (INPA); ArgentinaFil: Ercole, Mariano E. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Parasitología y Enfermedades Parasitarias; ArgentinaFil: Failla, Mauricio. Proyecto Patagonia Noreste; ArgentinaFil: Failla, Mauricio. Museo Provincial Patagónico de Ciencias Naturales Juan Carlos Salgado; ArgentinaFil: Perello, Mario C. Fundación Félix de Azara; ArgentinaFil: Birochio, Diego E. Universidad Nacional de Río Negro, Sede Atlántica; ArgentinaFil: Birochio, Diego E. Centro de Investigaciones y Transferencia Río Negro; ArgentinaFil: Abate, Sergio D. Universidad Nacional de Río Negro, Sede Atlántica; ArgentinaFil: Abate, Sergio D. Centro de Investigaciones y Transferencia; ArgentinaFil: Soricetti, Mariano. Universidad Nacional de Río Negro, Sede Atlántica; ArgentinaFil: Soricetti, Mariano. Centro de Investigaciones y Transferencia; ArgentinaFil: Ribicich, Mabel M. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Cátedra de Parasitología y Enfermedades Parasitarias; ArgentinaFil: Ribicich, Mabel M. Instituto de Investigaciones en Producción Animal (INPA); ArgentinaFil: Ribicich, Mabel M. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaTrichinellosis is a food-borne parasitic disease produced by different nematodes of the genus Trichinella. In Argentina, it is an endemic zoonosis and an important public health problem. The infection has been detected in domestic and wild animals. Trichinella spp. muscle larvae have anaerobic metabolism, which allows their survival in decaying tissues. The aim of this study was to evaluate the presence of Trichinella spp. in carnivorous and/or scavenger wild vertebrates - birds, mammals and reptiles - in northeastern Argentine Patagonia. Skeletal muscle samples from 141 animals, which were found killed on northeastern Argentine Patagonia roads, were analyzed by the artificial digestion method. None of the 141 samples were positive for larvae of Trichinella. These results suggest that Trichinella does not use these species to complete its cycle in this region of the continent and the absence of a significant alteration in the study area makes it difficult to transmit parasitic diseases. However, due to the limited number of samples assessed for some species, this could not be confirmed. The relevance of this study resides in the fact that it is the first systematic study in South America that considers birds, reptiles and mammals as potential hosts for Trichinella.Trichinellosis is a food-borne parasitic disease produced by different nematodes of the genus Trichinella. In Argentina, it is an endemic zoonosis and an important public health problem. The infection has been detected in domestic and wild animals. Trichinella spp. muscle larvae have anaerobic metabolism, which allows their survival in decaying tissues. The aim of this study was to evaluate the presence of Trichinella spp. in carnivorous and/or scavenger wild vertebrates - birds, mammals and reptiles - in northeastern Argentine Patagonia. Skeletal muscle samples from 141 animals, which were found killed on northeastern Argentine Patagonia roads, were analyzed by the artificial digestion method. None of the 141 samples were positive for larvae of Trichinella. These results suggest that Trichinella does not use these species to complete its cycle in this region of the continent and the absence of a significant alteration in the study area makes it difficult to transmit parasitic diseases. However, due to the limited number of samples assessed for some species, this could not be confirmed. The relevance of this study resides in the fact that it is the first systematic study in South America that considers birds, reptiles and mammals as potential hosts for Trichinella
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