461 research outputs found

    Liquid chromatographic determination of efficacy of incorporation of trimethoprim and sulfamethoxazole in brine shrimp (<i>Artemia</i> spp.) used for prophylactic chemotherapy of fish

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    The brine shrimp Artemia , an excellent live food source in aquaculture, has been studied as a carrier to deliver selected chemotherapeutic agents to fish for prophylactic treatment of infectious diseases. To monitor the efficiency of incorporation of trimethoprim and sulfamethoxazole in Artemia franciscana, a sensitive and specific analytical method was developed. It is based on homogenization of Artemia nauplii in methanol, extraction of lipids with hexane, solid-phase cleanup on C18 cartridges, and reversed-phase liquid chromatography with detection at 210 nm. The method is sensitive (detection limit, on the order of 3 µg/g with a sample quantity of 30 mg [dry weight]) and reproducible (coefficients of variation, 2.2 and 1.8% for trimethoprim and sulfamethoxazole at levels of 79.6 and 257 µg/g of body weight, respectively). Preliminary quantitative data indicated excellent uptake and persistence of both therapeutic agents in A. franciscana, with levels of 115 µg/g for trimethoprim and 277 µg/g for sulfamethoxazole

    A novel context ontology to facilitate interoperation of semantic services in environments with wearable devices

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    The LifeWear-Mobilized Lifestyle with Wearables (Lifewear) project attempts to create Ambient Intelligence (AmI) ecosystems by composing personalized services based on the user information, environmental conditions and reasoning outputs. Two of the most important benefits over traditional environments are 1) take advantage of wearable devices to get user information in a nonintrusive way and 2) integrate this information with other intelligent services and environmental sensors. This paper proposes a new ontology composed by the integration of users and services information, for semantically representing this information. Using an Enterprise Service Bus, this ontology is integrated in a semantic middleware to provide context-aware personalized and semantically annotated services, with discovery, composition and orchestration tasks. We show how these services support a real scenario proposed in the Lifewear project

    A characteristics framework for Semantic Information Systems Standards

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    Semantic Information Systems (IS) Standards play a critical role in the development of the networked economy. While their importance is undoubted by all stakeholders—such as businesses, policy makers, researchers, developers—the current state of research leaves a number of questions unaddressed. Terminological confusion exists around the notions of “business semantics”, “business-to-business interoperability”, and “interoperability standards” amongst others. And, moreover, a comprehensive understanding about the characteristics of Semantic IS Standards is missing. The paper addresses this gap in literature by developing a characteristics framework for Semantic IS Standards. Two case studies are used to check the applicability of the framework in a “real-life” context. The framework lays the foundation for future research in an important field of the IS discipline and supports practitioners in their efforts to analyze, compare, and evaluate Semantic IS Standard

    Ontological representation and governance of business semantics in compliant service networks

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    The Internet would enable new ways for service innovation and trading, as well as for analysing the resulting value networks, with an unprecedented level of scale and dynamics. Yet most related economic activities remain of a largely brittle and manual nature. Service-oriented business implementations focus on operational aspects at the cost of value creation aspects such as quality and regulatory compliance. Indeed they enforce how to carry out a certain business in a prefixed non-adaptive manner rather than capturing the semantics of a business domain in a way that would enable service systems to adapt their role in changing value propositions. In this paper we set requirements for SDL-compliant business service semantics, and propose a method for their ontological representation and governance. We demonstrate an implementation of our approach in the context of service-oriented Information Governance

    Multiplexed control of spin quantum memories in a photonic circuit

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    A central goal in many quantum information processing applications is a network of quantum memories that can be entangled with each other while being individually controlled and measured with high fidelity. This goal has motivated the development of programmable photonic integrated circuits (PICs) with integrated spin quantum memories using diamond color center spin-photon interfaces. However, this approach introduces a challenge in the microwave control of individual spins within closely packed registers. Here, we present a quantum-memory-integrated photonics platform capable of (i) the integration of multiple diamond color center spins into a cryogenically compatible, high-speed programmable PIC platform; (ii) selective manipulation of individual spin qubits addressed via tunable magnetic field gradients; and (iii) simultaneous control of multiple qubits using numerically optimized microwave pulse shaping. The combination of localized optical control, enabled by the PIC platform, together with selective spin manipulation opens the path to scalable quantum networks on intra-chip and inter-chip platforms.Comment: 10 pages, 4 figure

    The effects of symmetry on the dynamics of antigenic variation

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    In the studies of dynamics of pathogens and their interactions with a host immune system, an important role is played by the structure of antigenic variants associated with a pathogen. Using the example of a model of antigenic variation in malaria, we show how many of the observed dynamical regimes can be explained in terms of the symmetry of interactions between different antigenic variants. The results of this analysis are quite generic, and have wider implications for understanding the dynamics of immune escape of other parasites, as well as for the dynamics of multi-strain diseases.Comment: 21 pages, 4 figures; J. Math. Biol. (2012), Online Firs

    Global stability of enzymatic chain of full reversible Michaelis-Menten reactions

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    International audienceWe consider a chain of metabolic reactions catalyzed by enzymes, of reversible Michaelis-Menten type with full dynamics, i.e. not reduced with any quasi- steady state approximations. We study the corresponding dynamical system and show its global stability if the equilibrium exists. If the system is open, the equilibrium may not exist. The main tool is monotone systems theory. Finally we study the implications of these results for the study of coupled genetic-metabolic systems

    e3 service: A Critical Reflection and Future Research

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    Commercial services are of utmost importance for the economy. Due to the widespread use of information and communication technologies, many of these services may be delivered online by means of service value networks. To automate this delivery, however, issues such as composition, integration, and operationalization need to be addressed. In this paper, the authors share their long-term vision on composition of service value networks and describe relationships with fields such as cloud computing and enterprise computing. As a demonstration of the state of the art, capabilities and limitations of e 3 service are described and research challenges are defined
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