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81.
Lino J. Alvarez-Vázquez Francisco J. Fernández Aurea Martínez 《Journal of The Franklin Institute》2014
This work deals with an environmental problem related to controlling eutrophication inside a sensitive zone, by means of a regulation of the wastewater discharges in the region. After setting a detailed mathematical formulation of the optimal control problem posed on a free-boundary moving domain, we present several theoretical results on existence-regularity of optimal solutions, and their characterization by a first order optimality system. In the second part of the work a complete numerical algorithm for the resolution of the control problem is proposed, and several numerical examples are also given. 相似文献
82.
Silvia Izquierdo álvarez Eva Barrio Ollero Francisco Miguel Llinares Sanjuan Fabiola Lorente Martínez María Teresa Calvo Martín 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):159-166
Introduction:
Additional nucleotide substitutions in the 3′-untranslated region of prothrombin gene could explain some thrombotic events and also adverse pregnancy outcomes. We describe the first case of a homozygous 20209C>T mutation as the cause of deep vein thrombosis in a Spanish patient.Case and methods:
The 56-year-old male patient with a partial tear of the Achilles tendon developed calf (tibial) deep vein thrombosis after immobilization and was treated with an anticoagulant. To determine if the deep vein thrombosis was of genetic origin, a peripheral blood DNA sample was analysed for the presence of the three most frequent mutations associated with thrombotic events: factor V Leiden (1691G>A), prothrombin (20210G>A) and methylene tetrahydrofolate reductase (677C>T). The presence or absence of the normal allele of prothrombin could not be determined using the PTH-FV-MTHFR StripAssay (Vienna Lab).Results:
Comprehensive analysis showed that the patient had a variant interfering with the polymerase chain reaction product, we sequenced the entire prothrombin gene and found that the patient had a homozygous C>T mutation at position 20209; this interfered with the polymerase chain reaction product, which needs a C at this position to be able to bind to the wild-type probe present in the test strip.Conclusion:
The homozygous 20209C>T mutation and the presence of the mutation 677C>T in heterozygosity explained the patient’s deep vein thrombosis because the combination of mutations would increase the risk of thrombosis. Suitable genetic counselling should be provided to the patient and first-degree relatives as it important to detect prothrombin gene variants that could increase risk for thrombotic events. 相似文献83.
Miriam Delgado-Verde Javier Amores-Salvadó Gregorio Martín-de Castro José Emilio Navas-López 《知识管理研究与实践》2014,12(3):261-275
Although the importance of intellectual capital has already been highlighted in the management literature, few articles have focused on the importance of its green counterpart, green intellectual capital. Nowadays, when environmental concerns cannot be ignored by firms, it is therefore time to explore the role of green intellectual capital in environmental improvement. For that reason, our research aims to explore the relationships between green intellectual capital components and the environmental performance of the firms. In particular, we try to show the importance of green organizational and social capital in the development of environmental product innovations, which are vital to the development and implementation of environmental strategies since, as scholars have pointed out, they generate some of the greatest environmental impacts. The empirical results show that green organizational capital has an indirect impact on environmental product innovation through green social capital, meaning that the latter is a significant mediator of that relationship, and at the same time emphasizing that informal relationships play a key role in the improvement of the environmental performance of the firm and, more specifically, in the development of environmental product innovations. 相似文献
84.
The objective of this paper is to take an in-depth look, from a network perspective, at the role that social capital plays in improving knowledge exchange between organizations. To do this, we consider the three dimensions of social capital: the structural dimension, as measured by the position of firms bridging structural holes; the relational dimension, as gauged by the level of trust and friendship in each relationship; and the cognitive dimension, as estimated by the presence of a shared culture. We also evaluate the level of organizational and human capital present in terms of the firms in the network. Empirical evidence has been gathered from the Madrid Science Park in Spain by applying the social network analysis methodology. The results show that the three dimensions of social capital play a significant role in increasing knowledge exchange in this network, while human and organizational capital differences are only significant for a sub-sample. 相似文献
85.
Microfluidic devices allow for the production of physiologically relevant cellular microenvironments by including biomimetic hydrogels and generating controlled chemical gradients. During transport, the biomolecules interact in distinct ways with the fibrillar networks: as purely diffusive factors in the soluble fluid or bound to the matrix proteins. These two main mechanisms may regulate distinct cell responses in order to guide their directional migration: caused by the substrate-bound chemoattractant gradient (haptotaxis) or by the gradient established within the soluble fluid (chemotaxis). In this work 3D diffusion experiments, in combination with ELISA assays, are performed using microfluidic platforms in order to quantify the distribution of PDGF-BB and TGF-β1 across collagen and fibrin gels. Furthermore, to gain a deeper understanding of the fundamental processes, the experiments are reproduced by computer simulations based on a reaction-diffusion transport model. This model yields an accurate prediction of the experimental results, confirming that diffusion and binding phenomena are established within the microdevice. 相似文献
86.
87.
Manuel Jiménez Raya 《Educational Media International》2013,50(3-4):305-317
This paper discusses the professional development of primary modern language teachers through the use of new technologies. It explores the principles upon which the development of a multimedia learning environment (FLiP – Foreign Languages in Primary) was constructed. These entail principles of effective modern‐language teaching, principles of teacher education, and a conception of the effective teacher. In addition, ways in which technology can support the principles of effective professional development are discussed. Information technology can be extremely empowering, extremely motivating and extremely conducive to creating new and exciting teacher‐education environments. The most outstanding contribution is that multimedia environments can make teachers look beyond the immediate context thanks to the incorporation of indirect observation.Les multimédias dans la formation des enseignants en langues étrangères. Cet article discute le d´eveloppement professionnel des enseignants du primaire en langues modernes, grâce à l'utilisation des nouvelles technologies. Il explore les principes selon lesquels le développement d'un environnement multimédia a été construit (FLIP - Foreign Languages in Primary). Ils impliquent les principes de l'enseignement efficace des langues modernes, les principes de la formation des maîtres, et une conception du maître efficace. De plus, les façons dont la technologie vont soutenir les principes d'un développement efficace sont discutées. La technologie de l'information peut être très puissante, très motivante pour créer des nouveaux environnements excitants pour la formation des maîtres. La plus importante contribution est que les environnement mulitimédia amènent les maîtres à regarder au delà du contexte immédiat grâce à l'incorporation de l'observation indirecte.Multimedia in der Ausbildung von Lehrern für neue Sprachen. Dieses Papier erörtert die professionelle Entwicklung von Material zur Ausbildung von Grundstufenlehrern für moderne Sprachen durch die Verwendung neuer Technologien. Es vermittelt die Prinzipien, auf denen die Entwicklung einer Multimedia Lernumgebung ('FLIP - Foreign Languages in Primary') aufgebaut wurde. Diese enthalten Prinzipien modernen Sprachunterrichts, Prinzipien von Lehrerbildung und ein Konzept des 'wirksamen' Lehrers. Außerdem wird diskutiert, welche Technik die Prinzipien wirksamer professioneller Entwicklung unterstützen kann. Die Nutzung von Informationstechnologie kann extrem verstärkend, extrem motivierend und äußerst dienlich sein, neue und aufregende Möglichkeiten für die Lehrerbildung.zu schaffen. Der hervorragendste Beitrag ist, daß Multimediaumgebungen es Lehrern ermöglichen können, sich öber den unmittelbaren Kontext durch die Integration indirekter Beobachtung zu informieren. 相似文献
88.
89.
Macarena Sánchez-Izquierdo Alonso María Prieto Ursúa José M Caperos 《Educational gerontology》2017,43(12):650-661
The objective of this study was to assess the relationship between the institutionalization of a dependent elderly relative and the family caregiver’s mental health, quality of life and caregiving satisfaction. We present data from 140 family caregivers caring for elderly family members, of whom 77 continued to live with family members and 63 had been institutionalized. We evaluated the factors influencing the decision to institutionalize the dependent relative, the effect of institutionalization on the caregiver’s psychological well-being and quality of life and the impact of strategies to find the meaning and cope with the relative’s placement on the caregiver’s emotional health and quality of life. Care does not end after institutionalization, but the stressors the caregiver faces change. Our results suggest that finding meaning increases satisfaction and reduces feelings of overload. They show that after institutionalization, stressors affecting caregivers are partly relieved, and that finding meaning increases the caregiver’s satisfaction, while decreasing the degree of overload. Our data, further, indicates that a good relationship and cooperation between the staff of the institution and the family are important to improve the caregivers’ emotional health and quality of life, and consequently, the quality of life of the dependent elderly relative. 相似文献
90.
Elia Fernández-Díaz Lorea Fernández-Olaskoaga Prudencia Gutiérrez-Esteban 《Educational Action Research》2017,25(1):56-70
The study presented in this article forms part of a wider project promoting collaboration between junior researchers from different universities with the objective of rethinking and improving teaching practice in relation to the use of technology. The article describes research carried out during the 2012/13 academic year aimed at developing collaborative action research through technologically mediated agoras involving students from three Spanish universities. The main results of this study show that junior researchers improved their teaching practice through technologically mediated inside and outside agoras. In addition, the transformation of university classrooms into agoras enabled the negotiated reconstruction of knowledge for the analysis of good practice in the use of technology. Likewise, these agoras helped reduce limitations by breaking down the barriers of time, distance and resources for sharing findings and limitations between junior researchers. Furthermore, they pave the way for improvements and their implementation in learning processes during initial teacher training. 相似文献