427 research outputs found

    Interval training normalizes cCardiomyocyte function, diastolic Ca<sup>2+</sup> control, and SR Ca<sup>2+</sup> release synchronicity in a mouse model of diabetic cardiomyopathy

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    In the present study we explored the mechanisms behind excitation-contraction (EC)-coupling defects in cardiomyocytes from mice with type-2 diabetes (db/db), and determined whether 13-weeks of aerobic interval training could restore cardiomyocyte Ca2+ cycling and EC-coupling. Reduced contractility in cardiomyocytes isolated from sedentary db/db was associated with increased diastolic sarcoplasmic reticulum (SR)-Ca2+ leak, reduced synchrony of Ca2+ release, reduced transverse (T)-tubule density, and lower peak systolic and diastolic Ca2+ and caffeine-induced Ca2+ release. Additionally, the rate of SR Ca2+ ATPase (SERCA2a)-mediated Ca2+ uptake during diastole was reduced, whereas a faster recovery from caffeine-induced Ca2+ release indicated increased Na+/Ca2+- exchanger (NCX) activity. The increased SR-Ca2+ leak was attributed to increased Ca2+-calmodulindependent protein kinase (CaMKII&#948;) phosphorylation, supported by the normalization of SR-Ca2+ leak upon inhibition of CaMKII&#948; (AIP). Exercise training restored contractile function associated with restored SR Ca2+ release synchronicity, T-tubule density, twitch Ca2+ amplitude, SERCA2a and NCX activities, and SR-Ca2+ leak. The latter was associated with reduced phosphorylation of cytosolic CaMKII&#948;. Despite normal contractile function and Ca2+ handling after the training period, phospholamban was hyperphosphorylated at Serine-16. Protein kinase A (PKA) inhibition (H-89) in cardiomyocytes from the exercised db/db group abolished the differences in SR-Ca2+ load when compared with the sedentary db/db mice. EC-coupling changes were observed without changes in serum insulin or glucose levels, suggesting that the exercise training-induced effects are not via normalization of the diabetic condition. These data demonstrate that aerobic interval training almost completely restored the contractile function of the diabetic cardiomyocyte to levels close to sedentary wild type (WT)

    Eficiência da ureia revestida com polímeros, na produtividade de milho safrinha.

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    Em regiões tropicais e principalmente, sob cultivo em sistema de plantio direto, as perdas de N, na forma de NH3, por volatilização aliada à baixa disponibilidade hídrica, estão entre as principais causas de baixa produtividade de milho safrinha. Breda et al. (2010), constataram maior eficiência na utilização de ureia revestida com polímeros, em relação à redução das perdas de NH3 ocasionadas por volatilização. Consequentemente, ocasionando um melhor aproveitamento deste nutriente pelas plantas, podendo gerar incremento de produtividade. Em sistemas de plantio direto, onde há um maior acúmulo de resíduos vegetais na superfície do solo, as perdas de N, na forma de NH3, são maiores em relação a outros sistemas de cultivo, como por exemplo, o plantio convencional (VIERO, 2011). Contudo, o sistema plantio direto na palha, nos proporciona inúmeras vantagens em relação ao cultivo convencional, como por exemplo, menor suscetibilidade a erosão, controle de temperatura do solo, equilíbrio da micro e macro biota do solo, melhor conservação de água, dentre outras. Levando-nos a buscar alternativas eficientes para o seu manejo, principalmente na safrinha, onde estes benefícios são essenciais para o sucesso da lavoura. Diante do disposto acima, o objetivo deste estudo foi, avaliar o efeito da adubação nitrogenada protegida com polímeros, em plantas de milho cultivadas sob sistema de plantio direto, em regime de safrinha.Disponível em: http://www.cpao.embrapa.br/cds/milhosafrinha2013/PDF/61.pdf. Acesso em 18 dez. 2013

    Transpiration reduction as an answer to water stress: models versus measurements for irrigated olive trees in South Portugal

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    The so-called stress functions, allowing quantification of transpiration or evapotranspiration reduction, as an answer to water deficit stress (stress coefficient, Ks), are useful tools for irrigation scheduling. It is known that this coefficient depends on several variables and parameters, such as evapotranspiration rate, root patterns/density and soil properties. However, the most common Ks models with practical applicability do not include some of these factors and the experimental work on this matter is not abundant. A well-known model proposed in the FAO 56 manual uses two parameters: the allowable depletion (p) and the total available soil water (TAW) in the root zone, the input variable being the soil water depletion (SWD). We discuss the application of this model in olive trees under specific natural conditions. Two studies were conducted in Alentejo, South Portugal (2011 and 2017), in one intensive and one super intensive drip irrigated olive orchards (Olea europaea 'Arbequina'). Transpiration reduction was obtained from sap flow measurements. For both experiments, Ks was related to the estimated SWD. The experimental relationship was compared with modelling outputs. Experimental results show that, in both experiments, the Ks FAO 56 model only fits using parameters such as p= 0.05 and TAW = 350 mm. The suggested p in that manual is 0.7. Furthermore, for such soils, anisotropic canopy and small wetted area (drippers), 350 mm is much more than first approach estimates would suggest. The results can be related with the root system functioning and resilience of olive treesinfo:eu-repo/semantics/publishedVersio

    Vulnerability and the bioethics through the experiences of illness

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    Background: Vulnerable people are relatively or absolutely incapable of protecting their own interests. Vulnerability is an anthropological attribute of human beings due to the simple fact of being alive. Brazilian society has long been established as a matter through the eyes of social scientists. In the name of it, the vulnerability in the doctor-patient context is now being a much-discussed issue. Purpose: This study aims to analyze the current studies regarding the insertion of vulnerability in the health issue, reflexively dealing with the ethical matters involved, as well as with the narratives’ insertion in this process. Methods: This article is based on data extracted from Scientific Electronic Library Online (Scielo) and on secondary data from textbooks about vulnerability, ethics, physician-patient relationship and narratives. Results and discussion: Doctors are faced with dilemmas in clinical practice: moral, ethical, legal, social, religious and economic. On these occasions, question their own values. By listening carefully to the stories of patients, health professionals broaden their perspectives, organize and integrate complex situations, which assists in conducting these difficult situations. Conclusion: Reflect the concept of vulnerability raises (re) think health practices, particularly in bringing to light the social experience of illness and hospitalization of the patient

    The effect of large-decoherence on mixing-time in Continuous-time quantum walks on long-range interacting cycles

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    In this paper, we consider decoherence in continuous-time quantum walks on long-range interacting cycles (LRICs), which are the extensions of the cycle graphs. For this purpose, we use Gurvitz's model and assume that every node is monitored by the corresponding point contact induced the decoherence process. Then, we focus on large rates of decoherence and calculate the probability distribution analytically and obtain the lower and upper bounds of the mixing time. Our results prove that the mixing time is proportional to the rate of decoherence and the inverse of the distance parameter (\emph{m}) squared. This shows that the mixing time decreases with increasing the range of interaction. Also, what we obtain for \emph{m}=0 is in agreement with Fedichkin, Solenov and Tamon's results \cite{FST} for cycle, and see that the mixing time of CTQWs on cycle improves with adding interacting edges.Comment: 16 Pages, 2 Figure

    Terapêutica intravesical com bacilo de Calmette-Guérin no tratamento do carcinoma da bexiga / o que sabemos até agora

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    AbstractIntroductionThe use of intravesical Bacillus Calmette-Guérin is a valid option in the treatment of non-muscle invasive bladder tumors, making it the main subject of a lot of publications. The aim of the present study is to review and consolidate the data available about this subject.MethodsA review of the data available was made on PubMed with the keywords: “intravesical BCG” and “non-muscle invasive bladder cancer”. Original and review articles written in English or Portuguese were selected. We present the discussion alongside the results for structural purposes.Results and discussionScientific evidence strongly advises in favor of BCG use on intermediate and high risk tumors, due to its impact on the recurrence and possibly on the progression rates. It is important to be watchful for possible local and systemic side effects, that when detected call for a rightful therapeutically decision alongside the recommended schemes.ConclusionThe use of intravesical BCG with therapeutically purposes has strong evidence on the non-muscle invasive bladder tumors. More studies are needed in order to better understand the best administration scheme and its mechanism of action

    A Service Based Architecture for Multidisciplinary IoT Experiments with Crowdsourced Resources

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    Research on emerging networking paradigms, such as Mobile Crowdsensing Systems, requires new types of experiments to be conducted and an increasing spectrum of devices to be supported by experimenting facilities. In this work, we present a service based architecture for IoT testbeds which (a) exposes the operations of a testbed as services by following the Testbed as a Service (TBaaS) paradigm; (b) enables diverse facilities to be federated in a scalable and standardized way and (c) enables the seamless integration of crowdsourced resources (e.g. smartphones and wearables) and their abstraction as regular IoT resources. The architecture enables an experimenter to access a diverse set of resources and orchestrate experiments via a common interface by hiding the underlying heterogeneity and complexity. This way, the field of IoT experimentation with real resources is further promoted and broadened to also address researchers from other fields and discipline

    Asymptotic entanglement in a two-dimensional quantum walk

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    The evolution operator of a discrete-time quantum walk involves a conditional shift in position space which entangles the coin and position degrees of freedom of the walker. After several steps, the coin-position entanglement (CPE) converges to a well defined value which depends on the initial state. In this work we provide an analytical method which allows for the exact calculation of the asymptotic reduced density operator and the corresponding CPE for a discrete-time quantum walk on a two-dimensional lattice. We use the von Neumann entropy of the reduced density operator as an entanglement measure. The method is applied to the case of a Hadamard walk for which the dependence of the resulting CPE on initial conditions is obtained. Initial states leading to maximum or minimum CPE are identified and the relation between the coin or position entanglement present in the initial state of the walker and the final level of CPE is discussed. The CPE obtained from separable initial states satisfies an additivity property in terms of CPE of the corresponding one-dimensional cases. Non-local initial conditions are also considered and we find that the extreme case of an initial uniform position distribution leads to the largest CPE variation.Comment: Major revision. Improved structure. Theoretical results are now separated from specific examples. Most figures have been replaced by new versions. The paper is now significantly reduced in size: 11 pages, 7 figure

    Modelagem fuzzy para previsão da produtividade de goiabeira 'Paluma' em sistema agroindustrial em função da época de poda e do estado nutricional.

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    Abstract. As incertezas inerentes ao processo de produção de goiaba Paluma, principalmente quando se considera a época de poda e a avaliação do estado nutricional das plantas, podem interferir nos ganhos do fruticultor, pois a adubação representa boa parte dos custos de produção. Neste trabalho, apresentamos um modelo fuzzy para estimar a produtividade da goiabeira Paluma incorporando ao modelo as incertezas nos teores foliares de NPK e a época da poda. Consideraram-se nas relações fuzzy as tabelas de suficiência dos nutrientes e a experiência dos pesquisadores e produtores. O controlador fuzzy foi bem sucedido na tarefa de predizer a produtividade da goiabeira. Os resultados estimados quando comparados com os observados no campo apresentaram erro inferior a 10% para a maioria das amostras analisadas

    EVALUATION OF IN VITRO DISSOLUTION OF BENZNIDAZOLE AND BINARY MIXTURES: SOLID DISPERSIONS WITH HYDROXYPROPYLMETHYLCELLULOSE AND β-CYCLODEXTRIN INCLUSION COMPLEXES

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    Objective: To increase the solubility/dissolution of benznidazole (BNZ) in water using two systems: solid dispersions (SD) with hydroxypropylmethylcellulose (HPMC) and β-cyclodextrin (β-CD) inclusion complexes (IC).Methods: The samples were obtained by physical mixtures (PM), kneading (KN), evaporation (EV) and by spray-dryer (SY) atomization The analysis was based on results of in vitro dissolution and molecular modeling techniques.Results: Molecular modeling showed that BNZ can form β-CD complexes in different ways such as in an aqueous solution or a vacuum. In vitro dissolution showed significant improvement in BNZ solubility in the PM, SD and IC, and also that the β-CD IC promoted better solubility than SD with HPMC.Conclusion: Considering the data obtained, it is possible to consider the technique for the formation of β-CD IC as a more effective technique in promoting the improvement of BNZ solubility compared with getting SD with HPMC which, in turn, may increase the bioavailability of the drug and improve their pharmaceutical potential
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