801 research outputs found

    Age and Growth of Scotia Sea Icefish, Chaenocephalus aceratus, From the South Shetland Islands

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    Samples of Chaenocephalus aceratus (Lönnberg) were collected during a trawl survey carried out around the South Shetland Islands in January–February 2002. Fish were caught by commercial bottom trawl fishing down to 500 m depth, using a stratified randomized sampling design. As observed in other recent surveys within the same area, C. aceratus represented one of the predominant species. Overall, 357 specimens ranging from 13 and 67 cm (TL) were selected for the present study. Ages were estimated by counting annuli present in the sagittal otoliths, exposed by grinding and polishing along their sagittal plane. To estimate the precision of age data, we compared blind readings by readers from different institutions. The age range was 1–17 years for females and 1–15 years for males. Von Bertalanffy growth curves were fitted to the estimated age-length data for each sex. The estimated values of asymptotic length L∞ (cm) and K (year-1) were respectively 79.8 and 0.07 for females and 60.0 and 0.09 for males. The growth performance index ranged between 2 and 2.5, similar to that reported in other icefish. Sexual maturity was attained by females and males at about 10 and 9 years old respectively, at about 60% of their maximum estimated age. These results are compared with age and growth data available in the literature for C. aceratus, and discussed in the light of recent commercial exploitation

    Whiting (Merlangius merlangus) Grows Slower and Smaller in the Adriatic Sea: New Insights from a Comparison of Two Populations with a Time Interval of 30 Years

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    Nowadays, overexploitation and climate change are among the major threats to fish production all over the world. In this study, we focused our attention on the Adriatic Sea (AS), a shallow semi-enclosed sub-basin showing the highest exploitation level and warming trend over the last decades within the Mediterranean Sea. We investigated the life history traits and population dynamics of the cold-water species whiting (Merlangius merlangus, Gadidae) 30 years apart, which is one of the main commercial species in the Northern AS. The AS represents its southern limit of distribution, in accordance with the thermal preference of this cold-water species. Fish samples were collected monthly using a commercial bottom trawl within the periods 1990–1991 and 2020–2021. The historical comparison highlighted a recent reduction in large specimens (>25 cm total length, TL), which was not associated with trunked age structures, therefore indicating a decrease in growth performance over a period of 30 years (L∞90–91 = 29.5 cm TL; L∞20–21 = 22.8 cm TL). The current size at first sexual maturity was achieved within the first year of life, at around 16 cm TL for males and 17 cm TL for females. In the AS, whiting spawns in batches from December to March, showing a reproductive investment (gonadosomatic index) one order of magnitude higher in females than in males. Potential fecundity (F) ranged from 46,144 to 424,298, with it being heavily dependent on fish size. We hypothesize that the decreased growth performance might be related to a metabolic constraint, possibly related to the increased temperature and its consequences. Moreover, considering the detrimental effects of size reduction on reproductive potential, these findings suggest a potential endangerment situation for the long-term maintenance of whiting and cold-related species in the AS, which should be accounted for in setting management strategies

    Segundo informe del Observatorio de Costes y Financiación del Transporte Urbano Colectivo: encuesta a los gestores

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    A comienzos de 2012 se publicó el Primer Informe del Observatorio de Costes y Financiación del Transporte Urbano Colectivo (OTUC), creado con el apoyo y colaboración de la Asociación de Empresas del Transporte Urbano Colectivo (ATUC) que ha facilitado la adhesión de las principales empresas representantes del sector analizado, con el objetivo fundamental de estudiar las condiciones de explotación de las empresas de transporte urbano colectivo en superficie en España. Consolidado el proyecto iniciado por el Observatorio, en septiembre de 2013 se publica su Segundo Informe, en el que, como se realizó en el primero, y al objeto de conocer la visión de los gestores y la valoración que otorgan a los principales puntos críticos del negocio, se desarrolló una encuesta cuyos resultados se muestran en el presente trabajo.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Feeding ecology of the transparent goby <em>Aphia minuta</em> (Pisces, Gobiidae) in the northwestern Adriatic Sea

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    The feeding ecology of the transparent goby Aphia minuta was examined in spring (May 2003) in the coastal waters off Comacchio, in the northwestern Adriatic Sea. Stomach content analysis indicated A. minuta to be a planktivorous species, feeding exclusively on pelagic invertebrates. The diet composition was dominated by the calanoid copepods Acartia clausi and Temora longicornis, followed in decreasing order of importance by other copepods (especially calanoids and Oncaea spp.) and larvae of decapods, polychaetes and bivalves. A. minuta exhibited a generalistic feeding strategy with a relatively broad niche width. Abundant taxa in the environment, such as A. clausi and T. longicornis, were seldom selected, whereas rare taxa, such as larvae of polychaetes and decapods, were highly selected. According to the observed ontogenetic shift in diet, small-size individuals relied preferentially on juvenile T. longicornis and Oncaea spp., whereas large-sized specimens consumed preferably A. clausi and calanoids. The positive relationship found between prey and fish size may help to mitigate the intraspecific competition for food resources

    Implementation of binary stochastic STDP learning using chalcogenide-based memristive devices

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    The emergence of nano-scale memristive devices encouraged many different research areas to exploit their use in multiple applications. One of the proposed applications was to implement synaptic connections in bio-inspired neuromorphic systems. Large-scale neuromorphic hardware platforms are being developed with increasing number of neurons and synapses, having a critical bottleneck in the online learning capabilities. Spike-timing-dependent plasticity (STDP) is a widely used learning mechanism inspired by biology which updates the synaptic weight as a function of the temporal correlation between pre- and post-synaptic spikes. In this work, we demonstrate experimentally that binary stochastic STDP learning can be obtained from a memristor when the appropriate pulses are applied at both sides of the device

    A specific protein-enriched enteral formula decreases cortisolemia and improves plasma albumin and amino acid concentrations in elderly patients

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    <p>Abstract</p> <p>Background</p> <p>Old age is associated with an involuntary and progressive but physiological loss of muscle mass. The aim of this study was to evaluate the effects of exclusive consumption for 6 months of a protein-enriched enteral diet with a relatively high content of branched-chain amino acids on albuminemia, cortisolemia, plasma amino acids, insulin resistance, and inflammation biomarkers in elderly patients.</p> <p>Methods</p> <p>Thirty-two patients from the Clinical Nutrition Outpatient Unit at our hospital exclusively consumed a protein-enriched enteral diet for 6 months. Data were collected at baseline and at 3 and 6 months on anthropometric and biochemical parameters and on plasma concentrations of amino acids, cortisol, adrenocorticotropic hormone, urea, creatinine, insulin resistance, and inflammation biomarkers.</p> <p>Results</p> <p>The percentage of patients with albumin concentration below normal cut-off values decreased from 18% to 0% by the end of the study. At 6 months, concentrations of total plasma (<it>p </it>= 0.008) and essential amino acids (<it>p </it>= 0.011), especially branched-chain amino acids (<it>p </it>= 0.031), were higher versus baseline values, whereas 3-methylhistidine (<it>p </it>= 0.001), cortisol (<it>p </it>= 0.001) and adrenocorticotropic hormone (<it>p </it>= 0.004) levels were lower.</p> <p>Conclusions</p> <p>Regular intake of specific protein-enriched enteral formula increases plasma essential amino acids, especially branched-chain amino acids, and decreases cortisol and 3-methylhistidine, while plasma urea and creatinine remain unchanged.</p

    Silk fibroin nanoparticles constitute a vector for controlled release of resveratrol in an experimental model of inflammatory bowel disease in rats.

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    Purpose: We aimed to evaluate the intestinal anti-inflammatory properties of silk fibroin nanoparticles, around 100 nm in size, when loaded with the stilbene compound resveratrol, in an experimental model of rat colitis. Methods: Nanoparticles were loaded with resveratrol by adsorption. The biological effects of the resveratrol-loaded nanoparticles were tested both in vitro, in a cell culture of RAW 264.7 cells (mouse macrophages), and in vivo, in the trinitrobenzenesulfonic acid model of rat colitis, when administered intracolonically. Results: The resveratrol liberation in 1× phosphate-buffered saline (PBS; pH 7.4) was characterized by fast liberation, reaching the solubility limit in 3 hours, which was maintained over a period of 80 hours. The in vitro assays revealed immunomodulatory properties exerted by these resveratrol-loaded nanoparticles since they promoted macrophage activity in basal conditions and inhibited this activity when stimulated with lipopolysaccharide. The in vivo experiments showed that after evaluation of the macroscopic symptoms, inflammatory markers, and intestinal barrier function, the fibroin nanoparticles loaded with resveratrol had a better effect than the single treatments, being similar to that produced by the glucocorticoid dexamethasone. Conclusion: Silk fibroin nanoparticles constitute an attractive strategy for the controlled release of resveratrol, showing immunomodulatory properties and intestinal anti-inflammatory effects

    Análise do conteúdo de informação econômico-técnica nas páginas web de empresas de transporte urbano na Espanha

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    Purpose: This article analyzes to what extent do companies that provide urban passenger transport in Spain publish useful information on their websites that allows evaluating the management carried out in a given period. Themes: The first step was to select the sample of companies from those providing the service in the capitals of Spanish provinces, since this are the most relevant municipalities and taking into account their fundamental activity and their web pages’ layout. Development: A questionnaire of diverse items is then applied to the sample. The questionnaire emphasizes on aspects related to the companies’ organization, activity, technical production means, consumptions, human resources and economic information. Conclusions: Results are presented, both in terms of the population size of provincial capitals and in relation to the direct or indirect management of the service. These results reveal the scarce economic information offered, with the exception of tariffs and the number of lines. In addition, it was found that companies with direct management provide more information than those that manage the service indirectly.Propósito: en el presente trabajo se analiza en qué medida las empresas prestatarias del transporte urbano de pasajeros en España publican en sus webs información de utilidad que permita evaluar la gestión realizada en un determinado periodo. Temas: se procede a la selección de la muestra de empresas a partir de aquellas que prestan el servicio en las capitales de provincias españolas, por ser los municipios de mayor relevancia y teniendo en cuenta su actividad fundamental y la disposición de sus páginas web. Desarrollo: a dicha muestra se aplica un cuestionario de diversos ítems, que presta especial atención a aspectos relativos a su organización, actividad, medios de producción técnicos, consumos, recursos humanos e información económica. Conclusiones: los resultados se presentan tanto en función de la dimensión poblacional de las capitales de provincias como en relación a la gestión directa o indirecta del servicio. Tales resultados ponen de manifiesto la escasa información de carácter económico, a excepción de las tarifas y el número de líneas. Además, las empresas de gestión directa aportan más información que aquellas que gestionan el servicio de forma indirectaPropósito: neste artigo, analisa-se em que medida as empresas prestadoras do transporte público urbano de passageiros na Espanha publicam em suas páginas web informação de utilidade que permita avaliar a gestão realizada num determinado período. &nbsp; Temas: procede-se à seleção da amostra de empresas a partir daquelas que prestam o serviço nas capitais de estados espanhóis, por serem os municípios de maior relevância e considerando sua atividade fundamental e a disposição de suas páginas web. &nbsp; Desenvolvimento: a essa amostra, aplica-se um questionário de diversos itens que presta especial atenção a aspectos relativos a sua organização, atividade, meios de produção técnicos, consumo, recursos humanos e informação econômica. &nbsp; Conclusões: os resultados são apresentados tanto em função da dimensão populacional das capitais quanto em relação à gestão direta ou indireta do serviço. Esses resultados manifestam a escassa informação de caráter econômico, à exceção das tarifas e do número de linhas. Além disso, as empresas de gestão direta contribuem com mais informação em comparação àquelas que administram o serviço de forma indireta

    A randomized study of pomalidomide vs placebo in persons with myeloproliferative neoplasm-associated myelofibrosis and RBC-transfusion dependence

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    RBC-transfusion dependence is common in persons with myeloproliferative neoplasm (MPN)-associated myelofibrosis. The objective of this study was to determine the rates of RBC-transfusion independence after therapy with pomalidomide vs placebo in persons with MPN-associated myelofibrosis and RBC-transfusion dependence. Two hundred and fifty-two subjects (intent-to-treat (ITT) population) including 229 subjects confirmed by central review (modified ITT population) were randomly assigned (2:1) to pomalidomide or placebo. Trialists and subjects were blinded to treatment allocation. Primary end point was proportion of subjects achieving RBC-transfusion independence within 6 months. One hundred and fifty-two subjects received pomalidomide and 77 placebo. Response rates were 16% (95% confidence interval (CI), 11, 23%) vs 16% (8, 26% P=0.87). Response in the pomalidomide cohort was associated with ⩽4 U RBC/28 days (odds ratio (OR)=3.1; 0.9, 11.1), age ⩽65 (OR=2.3; 0.9, 5.5) and type of MPN-associated myelofibrosis (OR=2.6; 0.7, 9.5). Responses in the placebo cohort were associated with ⩽4 U RBC/28 days (OR=8.6; 0.9, 82.3), white blood cell at randomization >25 × 10(9)/l (OR=4.9; 0.8, 28.9) and interval from diagnosis to randomization >2 years (OR=4.9; 1.1, 21.9). Pomalidomide was associated with increased rates of oedema and neutropenia but these adverse effects were manageable. Pomalidomide and placebo had similar RBC-transfusion-independence response rates in persons with MPN-associated RBC-transfusion dependence
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