927 resultados para NX Arts in general


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Although pharmaceutical metabolites are found in the aquatic environment, their toxicity on living organisms is poorly studied in general. Endoxifen and 4-hydroxy-tamoxifen (4OHTam) are two metabolites of the widely used anticancer drug tamoxifen for the prevention and treatment of breast cancers. Both metabolites have a high pharmacological potency in vertebrates, attributing prodrug characteristics to tamoxifen. Tamoxifen and its metabolites are body-excreted by patients, and the parent compound is found in sewage treatment plan effluents and natural waters. The toxicity of these potent metabolites on non-target aquatic species is unknown, which forces environmental risk assessors to predict their toxicity on aquatic species using knowledge on the parent compounds. Therefore, the aim of this study was to assess the sensitivity of two generations of the freshwater microcrustacean Daphnia pulex towards 4OHTam and endoxifen. Two chronic tests of 4OHTam and endoxifen were run in parallel and several endpoints were assessed. The results show that the metabolites 4OHTam and endoxifen induced reproductive and survival effects. For both metabolites, the sensitivity of D. pulex increased in the second generation. The intrinsic rate of natural increase (r) decreased with increasing 4OHTam and endoxifen concentrations. The No-Observed Effect Concentrations (NOECs) calculated for the reproduction of the second generation exposed to 4OHTam and endoxifen were <1.8 and 4.3μg/L, respectively, whereas the NOECs that were calculated for the intrinsic rate of natural increase were <1.8 and 0.4μg/L, respectively. Our study raises questions about prodrug and active metabolites in environmental toxicology assessments of pharmaceuticals. Our findings also emphasize the importance of performing long-term experiments and considering multi-endpoints instead of the standard reproduction outcome.

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Electricity is a strategic service in modern societies. Thus, it is extremely important for governments to be able to guarantee an affordable and reliable supply, which depends to a great extent on an adequate expansion of the generation and transmission capacities. Cross- border integration of electricity markets creates new challenges for the regulators, since the evolution of the market is now influenced by the characteristics and policies of neighbouring countries. There is still no agreement on why and how regions should integrate their electricity markets. The aim of this thesis is to improve the understanding of integrated electricity markets and how their behaviour depends on the prevailing characteristics of the national markets and the policies implemented in each country. We developed a simulation model to analyse under what circumstances integration is desirable. This model is used to study three cases of interconnection between two countries. Several policies regarding interconnection expansion and operation, combined with different generation capacity adequacy mechanisms, are evaluated. The thesis is composed of three papers. The first paper presents a detailed description of the model and an analysis of the case of Colombia and Ecuador. It shows that market coupling can bring important benefits, but the relative size of the countries can lead to import dependency issues in the smaller country. The second paper compares the case of Colombia and Ecuador with the case of Great Britain and France. These countries are significantly different in terms of electricity sources, hydro- storage capacity, complementarity and demand growth. We show that complementarity is essential in order to obtain benefits from integration, while higher demand growth and hydro- storage capacity can lead to counterintuitive outcomes, thus complicating policy design. In the third paper, an extended version of the model presented in the first paper is used to analyse the case of Finland and its interconnection with Russia. Different trading arrangements are considered. We conclude that unless interconnection capacity is expanded, the current trading arrangement, where a single trader owns the transmission rights and limits the flow during peak hours, is beneficial for Finland. In case of interconnection expansion, market coupling would be preferable. We also show that the costs of maintaining a strategic reserve in Finland are justified in order to limit import dependency, while still reaping the benefits of interconnection. In general, we conclude that electricity market integration can bring benefits if the right policies are implemented. However, a large interconnection capacity is only desirable if the countries exhibit significant complementarity and trust each other. The outcomes of policies aimed at guaranteeing security of supply at a national level can be quite counterintuitive due to the interactions between neighbouring countries and their effects on interconnection and generation investments. Thus, it is important for regulators to understand these interactions and coordinate their decisions in order to take advantage of the interconnection without putting security of supply at risk. But it must be taken into account that even when integration brings benefits to the region, some market participants lose and might try to hinder the integration process. -- Dans les sociétés modernes, l'électricité est un service stratégique. Il est donc extrêmement important pour les gouvernements de pouvoir garantir la sécurité d'approvisionnement à des prix abordables. Ceci dépend en grande mesure d'une expansion adéquate des capacités de génération et de transmission. L'intégration des marchés électriques pose des nouveaux défis pour les régulateurs, puisque l'évolution du marché est maintenant influencée par les caractéristiques et les politiques des pays voisins. Il n'est pas encore claire pourquoi ni comment les marches électriques devraient s'intégrer. L'objectif de cette thèse est d'améliorer la compréhension des marchés intégrés d'électricité et de leur comportement en fonction des caractéristiques et politiques de chaque pays. Un modèle de simulation est proposé pour étudier les conditions dans lesquelles l'intégration est désirable. Ce modèle est utilisé pour étudier trois cas d'interconnexion entre deux pays. Plusieurs politiques concernant l'expansion et l'opération de l'interconnexion, combinées avec différents mécanismes de rémunération de la capacité, sont évalués. Cette thèse est compose de trois articles. Le premier présente une description détaillée du modèle et une analyse du cas de la Colombie et de l'Equateur. Il montre que le couplage de marchés peut amener des bénéfices importants ; cependant, la différence de taille entre pays peut créer des soucis de dépendance aux importations pour le pays le plus petit. Le second papier compare le cas de la Colombie et l'Equateur avec le cas de la Grande Bretagne et de la France. Ces pays sont très différents en termes de ressources, taille des réservoirs d'accumulation pour l'hydro, complémentarité et croissance de la demande. Nos résultats montrent que la complémentarité joue un rôle essentiel dans l'obtention des bénéfices potentiels de l'intégration, alors qu'un taux élevé de croissance de la demande, ainsi qu'une grande capacité de stockage, mènent à des résultats contre-intuitifs, ce qui complique les décisions des régulateurs. Dans le troisième article, une extension du modèle présenté dans le premier article est utilisée pour analyser le cas de la Finlande et de la Russie. Différentes règles pour les échanges internationaux d'électricité sont considérées. Nos résultats indiquent qu'à un faible niveau d'interconnexion, la situation actuelle, où un marchand unique possède les droits de transmission et limite le flux pendant les heures de pointe, est bénéfique pour la Finlande. Cependant, en cas d'expansion de la capacité d'interconnexion, «market coupling» est préférable. préférable. Dans tous les cas, la Finlande a intérêt à garder une réserve stratégique, car même si cette politique entraine des coûts, elle lui permet de profiter des avantages de l'intégration tout en limitant ca dépendance envers les importations. En général, nous concluons que si les politiques adéquates sont implémentées, l'intégration des marchés électriques peut amener des bénéfices. Cependant, une grande capacité d'interconnexion n'est désirable que si les pays ont une complémentarité importante et il existe une confiance mutuelle. Les résultats des politiques qui cherchent à préserver la sécurité d'approvisionnement au niveau national peuvent être très contre-intuitifs, étant données les interactions entre les pays voisins et leurs effets sur les investissements en génération et en interconnexion. Il est donc très important pour les régulateurs de comprendre ces interactions et de coordonner décisions à fin de pouvoir profiter de l'interconnexion sans mettre en danger la sécurité d'approvisionnement. Mais il faut être conscients que même quand l'intégration amène de bénéfices pour la région, certains participants au marché sont perdants et pourraient essayer de bloquer le processus d'intégration.

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L’objectiu principal d’aquesta investigació és analitzar per què les arts de cos estan tan presents en els museus del segle XXI. Per fer-ho, ens centrarem primer en conèixer la història de les arts del cos des dels seus inicis al carrer o galeries alternatives fins a l’entrada al museu. En segon lloc, farem una aproximació a l’evolució dels museus centrant-nos en els segles XX i XXI. En tercer lloc, investigarem com les arts del cos entren als museus i farem una recerca d’aquestes arts en el museu del segle XXI

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In vitro organogenesis of Citrus was studied for the genotypes Citrus sinensis cv. 'Natal', C. limonia, C. volkameriana, and C. aurantium, with the use of epicotyl segments-derived explants, cultured in MT salts and vitamins medium supplemented with different concentrations of 6-benzylaminopurine (BAP - 0.0; 0.5; 1.0; 1.5 or 2.0 mg L-1). For the recalcitrant genotypes C. limonia and C. aurantium the in vitro organogenesis was also studied with internodal segments-derived explants, cultured in MT salts and vitamins medium supplemented with 0; 0.5; 1.0; 2.0, or 4.0 mg L-1 of BAP. The efficiency of culture medium supplementation with the combination of BAP (0.0; 1.0, or 2.0 mg L-1) and NAA (1-naphthaleneacetic acid - 0.0; 0.3, or 0.5 mg L-1) in the development of adventitious shoots was evaluated for C. aurantium. Culture medium supplementation with BAP is not essential for the adventitious shoots development in the four genotypes studied when epicotyl segments-derived explants are used. In general, culture media supplementation with BAP decreased the percentage of responsive explants excepted for C. sinensis cv. 'Natal' and C. limonia when the concentrations of 1.5 and 2.0 mg/L were used. The presence of cytokinin, in concentrations up to 2 mg/L, stimulated the in vitro organogenesis when internodal segments-derived explants were used for C. limonia and C. aurantium. For C. aurantium no adventitious shoots developed in explants (internodal segments) cultured in basal culture medium, without BAP supplementation. Although no statistic differences could be detected, culture media supplementation with the combination of BAP and NAA favored the development of adventitious shoots in C. aurantium. The best concentration of NAA varied according to BAP concentration. The results presented herein, show that Citrus in vitro organogenesis depends on the interaction of culture medium composition, explant differentiation level, and genotype.

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The objective of this study was to resolve how a privately owned health club can retain their existing customers. It was also resolved why there is a need for customer retention in general, and what the constructs leading to retention are. In addition, the relationship between customer satisfaction and customer retention was studied and discussed.

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Background: Although the studies published so far have found an affectation in the Health Related Quality of Life (HRQOL) in both psychiatric and substance use dependence disorders, very few studies have applied HRQOL as an assessment measure in patients suffering both comorbid conditions, or Dual Diagnosis. The aim of the current study was to assess HRQOL in a group of patients with Dual Diagnosis compared to two other non-comorbid groups and to determine what clinical factors are related to HRQOL. Methods: Cross-sectional assessment of three experimental groups was made through the Short Form 36 Item Health Survey (SF-36). The sample consisted of a group with Dual Diagnosis (DD; N=35), one with Severe Mental Illness alone (SMI; N=35) and another one with Substance Use Dependence alone (SUD; N=35). The sample was composed only by males. To assess the clinical correlates of SF-36 HRQOL, lineal regression analyses were carried out. Results: The DD group showed lower scores in most of the subscales, and in the mental health domain. The group with SUD showed in general a better state in the HRQOL while the group with SMI held an intermediate position with respect to the other two groups. Daily medication, suicidal attempts and daily number of coffees were significantly associated to HRQOL, especially in the DD group. Conclusions: The DD group showed lower self-reported mental health quality of life. Assessment of HRQOL in dual patients allows to identify specific needs in this population, and may help to establish therapeutic goals to improve interventions.

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The age of erythrocyte concentrates (EC) in transfusion medicine and the adverse outcomes when transfusing long-term-stored EC are highly controversial issues. Whereas the definition of a short-term-stored EC or a long-term-stored EC is unclear in clinical trials, data based on in vitro storage assays can help defining a limit in addition of the expiration date. The present review merges together these data in order to highlight an EC age cut-off and points out potential misleading consideration. The analysis of in vitro data highlights the presence of reversible and irreversible storage lesions and demonstrates that red blood cells (RBC) exhibit two limits during storage: one around 2 weeks and another one around 4 weeks of storage. Of particular importance, the first lesions to appear, i.e. the reversible ones, are per se reversible once transfused, whereas the irreversible lesions are not. In clinical trials, the EC age cut-off for short-term storage is in general fewer than 14 days (11 ± 4 days) and more disperse for long-term-stored EC (17 ± 13 days), regardless the clinical outcomes. Taking together, EC age cut-off in clinical trials does not totally fall into line of in vitro aging data, whereas it is the key criteria in clinical studies. Long-term-stored EC considered in clinical trials are not probably old enough to answer the question: "Does transfusion of long-term-stored EC (older than 4 weeks) result in worse clinical outcomes?" Depending on ethical concerns and clinical practices, older EC than currently assayed in clinical trials should have to be considered. These two worlds trying to understand the aging of erythrocytes and the impact on patients do not seem to speak the same language.

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Purpose: Atheromatic plaque progression is affected, among others phenomena, by biomechanical, biochemical, and physiological factors. In this paper, the authors introduce a novel framework able to provide both morphological (vessel radius, plaque thickness, and type) and biomechanical (wall shear stress and Von Mises stress) indices of coronary arteries. Methods: First, the approach reconstructs the three-dimensional morphology of the vessel from intravascular ultrasound(IVUS) and Angiographic sequences, requiring minimal user interaction. Then, a computational pipeline allows to automatically assess fluid-dynamic and mechanical indices. Ten coronary arteries are analyzed illustrating the capabilities of the tool and confirming previous technical and clinical observations. Results: The relations between the arterial indices obtained by IVUS measurement and simulations have been quantitatively analyzed along the whole surface of the artery, extending the analysis of the coronary arteries shown in previous state of the art studies. Additionally, for the first time in the literature, the framework allows the computation of the membrane stresses using a simplified mechanical model of the arterial wall. Conclusions: Circumferentially (within a given frame), statistical analysis shows an inverse relation between the wall shear stress and the plaque thickness. At the global level (comparing a frame within the entire vessel), it is observed that heavy plaque accumulations are in general calcified and are located in the areas of the vessel having high wall shear stress. Finally, in their experiments the inverse proportionality between fluid and structural stresses is observed.

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Brain oxidative processes play a major role in age-related cognitive decline, thus consumption of antioxidant-rich foods might help preserve cognition. Our aim was to assess whether consumption of antioxidant-rich foods in the Mediterranean diet relates to cognitive function in the elderly. In asymptomatic subjects at high cardiovascular risk (n = 447; 52% women; age 55-80 y) enrolled in the PREDIMED study, a primary prevention dietary-intervention trial, we assessed food intake and cardiovascular risk profile, determined apolipoprotein E genotype, and used neuropsychological tests to evaluate cognitive function.We also measured urinary polyphenols as an objective biomarker of intake. Associations between energy-adjusted food consumption, urinary polyphenols, and cognitive scores were assessed by multiple linear regression models adjusted for potential confounders. Consumption of some foods was independently related to better cognitive function. The specific associations [regression coefficients (95% confidence intervals)] were: total olive oil with immediate verbal memory [0.755 (0.151-1.358)]; virgin olive oil and coffee with delayed verbal memory [0.163 (0.010-0.316) and 0.294 (0.055-0.534), respectively];walnuts with working memory [1.191 (0.061-2.322)]; and wine with Mini-Mental State Examination scores [0.252 (0.006-0.496)]. Urinary polyphenols were associated with better scores in immediate verbal memory [1.208 (0.236-2.180)]. Increased consumption of antioxidant-rich foods in general and of polyphenols in particular is associated with better cognitive performance in elderly subjects at high cardiovascular risk. The results reinforce the notion that Mediterranean diet components might counteract age-related cognitive decline.

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Paperiteollisuus on ollut perinteisesti fragmentoitunut toimiala, mutta viime vuosikymmenen aikana konsolidoitumisprosessi on kiihtynyt. Yrityskaupat ja fuusiot ovat muuttaneet paperiteollisuuden markkinarakennetta merkittävästi. Työn tavoitteena oli tutkia yleisesti markkinarakenteen vaikutusta liiketoiminnan tuloksiin sekä analysoida yrityskauppojen ja fuusioiden syitä, tuloksia ja rajoituksia. Tavoitteena oli myös tutkia paperiteollisuuden konsolidoitumisen vaikutuksia hintakehitykseen, hintaheilahteluihin ja kannattavuuteen. Keskeisenä syynä konsolidoitumiskehitykselle voidaan pitää uusien paperikoneiden huomattavaa investointikustannusten kasvua. Toinen tärkeä tekijä yhdentymiskehitykselle on se, että paperiteollisuus on saavuttanut elinkaaren kypsyysvaiheen Euroopassa, Pohjois-Amerikassa ja Japanissa. Yrityskauppojen ja fuusioiden motiiveja paperiteollisuudessa ovat mm. kasvu kypsillä markkinoilla, tarve parantaa taloudellista tulosta, mahdollisuus toimia globaalisti ja hyödyntää siitä saatavat edut tai mahdollisuus parempaan arvoketjun hallintaan. Näyttää siltä, että suurempien paperiteollisuusyritysten kannattavuus ei ole parempi kuin pienemmillä yrityksillä. Lisäksi useimmissa paperiteollisuuden yrityskaupoissa ja fuusioissa näyttäisi ostavan osapuolen kurssikehitys ilmoitusta seuraavana päivänä olevan negatiivinen.

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Le médecin praticien est souvent bien sensibilisé aux indications à l'hémodialyse au cours de l'insuffisance rénale sévère, que celle-ci soit aiguë ou chronique. En dehors des indications traditionnelles à une épuration extrarénale, il existe certaines situations comme des intoxications (metformine, éthylène glycol ou lithium) et d'autres conditions (hypercalcémie, lyse tumorale), dans lesquelles l'hémodialyse intermittente représente le traitement le plus efficace, voire le seul. Bien que ces situations demeurent peu fréquentes, il est décisif de les reconnaître rapidement The medical practitioner is in general well aware of the indications for hemodialysis in severe, acute or chronic renal insufficiency. Apart from the traditional indications for renal replacement therapy, there are some cases such as metfomin and ethylene glycol poisoning, lithium intoxication severe hypercalcemia and tumor lysis syndrome, in which intermittent hemodialysis is the most effective treatment, or sometimes the only effective one. Although these situations remain infrequent, it is crucial to recognize them as quickly as possible.

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[cat] En aquest article es considera un problema de cooperació entre agents on cada agent realitza una contribució (diners, capital, treball, esforç) per tal d'obtenir un benefici comú a repartir. El repartiment proporcional respecte a les contribucions és una distribució que pertany al nucli del joc cooperatiu associat. A partir d'aquest model bàsic s'introdueix un agent extern que pot realitzar una determinada aportació que serveix per avaluar el potencial benefici de cada subcoalició d'agents si aquest nou agent finalment entrés. Aquesta anàlisi pot produir que el poder relatiu dels agents hagi variat. en concret s'avalua si la distribució proporcional és encara robusta des del punt de vista de la seva pertinença al conjunt de negociació. Amb aquest objectiu, analitzem el problema utilitzant el model de joc cooperatius amb estructura de coalició. Donat que, en general, la distribució proporcional, no pertany al conjunt de negociació, s'estudia una condició suficient per a que així sigui. També enunciem una condició necessària, i finalment es proposa una condició suficient que garanteix que el repartiment proporcional és la única distribució existent dins del conjunt de negociació.