976 resultados para FUNCTIONAL APPLICATIONS


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Taking functional programming to its extremities in search of simplicity still requires integration with other development (e.g. formal) methods. Induction is the key to deriving and verifying functional programs, but can be simplified through packaging proofs with functions, particularly folds, on data (structures). Totally Functional Programming avoids the complexities of interpretation by directly representing data (structures) as platonic combinators - the functions characteristic to the data. The link between the two simplifications is that platonic combinators are a kind of partially-applied fold, which means that platonic combinators inherit fold-theoretic properties, but with some apparent simplifications due to the platonic combinator representation. However, despite observable behaviour within functional programming that suggests that TFP is widely-applicable, significant work remains before TFP as such could be widely adopted.

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Spatial data has now been used extensively in the Web environment, providing online customized maps and supporting map-based applications. The full potential of Web-based spatial applications, however, has yet to be achieved due to performance issues related to the large sizes and high complexity of spatial data. In this paper, we introduce a multiresolution approach to spatial data management and query processing such that the database server can choose spatial data at the right resolution level for different Web applications. One highly desirable property of the proposed approach is that the server-side processing cost and network traffic can be reduced when the level of resolution required by applications are low. Another advantage is that our approach pushes complex multiresolution structures and algorithms into the spatial database engine. That is, the developer of spatial Web applications needs not to be concerned with such complexity. This paper explains the basic idea, technical feasibility and applications of multiresolution spatial databases.

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This paper is devoted to the study of the class of continuous and bounded functions f : [0, infinity] -> X for which exists omega > 0 such that lim(t ->infinity) (f (t + omega) - f (t)) = 0 (in the sequel called S-asymptotically omega-periodic functions). We discuss qualitative properties and establish some relationships between this type of functions and the class of asymptotically omega-periodic functions. We also study the existence of S-asymptotically omega-periodic mild solutions of the first-order abstract Cauchy problem in Banach spaces. (C) 2008 Elsevier Inc. All rights reserved.

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Tight control over circulating juvenile hormone (JH) levels is of prime importance in an insect`s life cycle. Consequently, enzymes involved in JH metabolism, especially juvenile hormone esterases (JHEs), play major roles during metamorphosis and reproduction. In the highly eusocial Hymenoptera, JH has been co-opted into additional functions, primarily in the development of the queen and worker castes and in age-related behavioral development of workers. Within a set of 21 carboxylesterases predicted in the honey bee genome we identified one gene (Amjhe-like) that contained the main functional motifs of insect JHEs. Its transcript levels during larval development showed a maximum at the switch from feeding to spinning behavior, coinciding with a JH titer minimum. In adult workers, the highest levels were observed in nurse bees, where a low JH titer is required to prevent the switch to foraging. Functional assays showed that Amjhe-like expression is induced by JH-III and suppressed by 20-hydroxyecdysone. RNAi-mediated silencing of Amjhe-like gene function resulted in a six-fold increase in the JH titer in adult worker bees. The temporal profile of Amjhe-like expression in larval and adult workers, the pattern of hormonal regulation and the knockdown phenotype are consistent with the function of this gene as an authentic JHE. (C) 2008 Elsevier Inc. All rights reserved.

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We report here genome sequences and comparative analyses of three closely related parasitoid wasps: Nasonia vitripennis, N. giraulti, and N. longicornis. Parasitoids are important regulators of arthropod populations, including major agricultural pests and disease vectors, and Nasonia is an emerging genetic model, particularly for evolutionary and developmental genetics. Key findings include the identification of a functional DNA methylation tool kit; hymenopteran-specific genes including diverse venoms; lateral gene transfers among Pox viruses, Wolbachia, and Nasonia; and the rapid evolution of genes involved in nuclear-mitochondrial interactions that are implicated in speciation. Newly developed genome resources advance Nasonia for genetic research, accelerate mapping and cloning of quantitative trait loci, and will ultimately provide tools and knowledge for further increasing the utility of parasitoids as pest insect-control agents.

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The capacity to distinguish colony members from strangers is a key component in social life. In social insects, this extends to the brood and involves discrimination of queen eggs. Chemical substances communicate colony affiliation for both adults and brood; thus, in theory, all colony members should be able to recognize fellow nestmates. In this study, we investigate the ability of Dinoponera quadriceps workers to discriminate nestmate and non-nestmate eggs based on cuticular hydrocarbon composition. We analyzed whether cuticular hydrocarbons present on the eggs provide cues of discrimination. The results show that egg recognition in D. quadriceps is related to both age and the functional role of workers. Brood care workers were able to distinguish nestmate from non-nestmate eggs, while callow and forager workers were unable to do so.

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A bounded continuous function it u : [0, infinity) -> X is said to be S-asymptotically omega-periodic if lim(t ->infinity)[u(t + omega) - u(t)] = 0. This paper is devoted to study the existence and qualitative properties of S-asymptotically omega-periodic mild solutions for some classes of abstract neutral functional differential equations with infinite delay, Furthermore, applications to partial differential equations are given.

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The electrocatalytic activity of Pt and RuO(2) mixed electrodes of different compositions towards methanol oxidation was investigated. The catalysts were prepared by thermal decomposition of polymeric precursors and characterized by energy dispersive X-ray, scanning electronic microscopy, X-ray diffraction and cyclic voltammetry. This preparation method allowed obtaining uniform films with controlled stoichiometry and high surface area. Cyclic voltammetry experiments in the presence of methanol showed that mixed electrodes decreased the potential peak of methanol oxidation by approximately 100 mV (RHE) when compared to the electrode containing only Pt. In addition, voltammetric experiments indicated that the Pt(0.6)Ru(0.4)O(y) electrode led to higher oxidation current densities at lower potentials. Chronoamperometry experiments confirmed the contribution of RuO(2) to the catalytic activity as well as the better performance of the Pt(0.6)Ru(0.4)O(y) electrode composition. Formic acid and CO(2) were identified as being the reaction products formed in the electrolysis performed at 400 and 600 mV. The relative formation of CO(2) was favored in the electrolysis performed at 400 mV (RHE) with the Pt(0.6)Ru(0.4)O(y) electrode. The presence of RuO(2) in Pt-Ru-based electrodes is important for improving the catalytic activity towards methanol electrooxidation. Moreover, the thermal decomposition of polymeric precursors seems to be a promising route for the production of catalysts applicable to DMFC. (C) 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.

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A variety of nanostructures are being investigated as functional drug carriers for treatment of a wide range of diseases, most notably cardiovascular defects, autoimmune diseases, and cancer. The aim of this present contribution is to evaluate potentially applicable nanomaterials in the diagnosis and treatment of cancer due to their photophysical and photobiological properties and complexation behavior. The delivery systems consisted of chloro-aluminum phthalocyanine associated with beta-cyclodextrin and hydroxypropyl-beta-cyclodextrin. The preparation of the complex and its stoichiometry in an ethanol/buffer (3:1) solution were studied by spectroscopic techniques, which were defined as 1:2. The inclusion complex in the nanometer scale was observed on the basis of changes to the spectroscopic properties. The singlet oxygen production and complex photophysical parameters were determined by measuring luminescence at 1270 nm and by steady state and time resolved spectroscopic, respectively. The preparation of the complex was tested and analyzed with regard to cellular damage by visible light activation. The inclusion complex showed a higher singlet oxygen quantum yield compared with other systems and other photoactive dyes. There was also a reduction in the fluorescence quantum yield compared with the results obtained for zinc phthalocyanine in organic medium. The results reported clearly that the inclusion complex chloro-aluminum phthalocyanine/cyclodextrin showed some changes in its spectroscopy properties leading to better biodistribution and biocompatibility with a potential application in photodynamic therapy, especially in the case of neoplasy. Additionally, it also has non-oncological applications as a drug delivery system.

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Computational models complement laboratory experimentation for efficient identification of MHC-binding peptides and T-cell epitopes. Methods for prediction of MHC-binding peptides include binding motifs, quantitative matrices, artificial neural networks, hidden Markov models, and molecular modelling. Models derived by these methods have been successfully used for prediction of T-cell epitopes in cancer, autoimmunity, infectious disease, and allergy. For maximum benefit, the use of computer models must be treated as experiments analogous to standard laboratory procedures and performed according to strict standards. This requires careful selection of data for model building, and adequate testing and validation. A range of web-based databases and MHC-binding prediction programs are available. Although some available prediction programs for particular MHC alleles have reasonable accuracy, there is no guarantee that all models produce good quality predictions. In this article, we present and discuss a framework for modelling, testing, and applications of computational methods used in predictions of T-cell epitopes. (C) 2004 Elsevier Inc. All rights reserved.

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In this paper, we describe the blue photoluminescence (PL) observed in the multi-component oxosalt phosphor GdVO(4)center dot Ce(3+). Different doping concentrations (0.25-1 mol%) and heat treatment (900-1100 degrees C) were used to evaluate which conditions would lead to the most suitable blue phosphor for optimal display performance. The cerium doping concentration influences the profile of the emission spectrum (broad peak at 412 nm under UV excitation at 330 nm), as reflected on the values of chromaticity coordinates. On the basis of luminescent properties, we can conclude that, among the phosphors prepared in this work the most adequate for a blue display is the one obtained via the combustion method using glycine as fuel, a 0.50 mol% cerium doping concentration, and heat treatment at 1000 degrees C.

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Functional gastrointestinal disorders commonly affect people of all ages, including the elderly. While population-based studies report significant psychological morbidity in people diagnosed with these disorders it is not clear what effect age has in explaining this relationship. We hypothesised that psychological distress would be higher in older versus younger persons with a FGID from the community. A random sample of 4500 subjects were mailed a questionnaire on gastrointestinal symptoms in the past 12 months (response rate = 72%). Of those fulfilling Rome I criteria for a FGID (n = 988) we then classified subjects into older (>60 years) (n =126) versus younger (18-59 years) (n = 862) categories. Psychological variables included anxiety and depression (Delusions Symptom States Inventory) and neuroticism and extroversion (Eysenck Personality Inventory). Quality of life was assessed using the valid SF-12. Anxiety (4.5 vs. 3.1), depression (3.0 vs. 1.8) and neuroticism (5.7 vs. 4.9) were significantly higher in younger versus older subjects with a FGID. While mental functioning (43.1 vs. 48.3) was significantly more impaired in younger versus older subjects, the reverse was found for physical functioning (48.7 vs. 40.8). Younger people with a FGID experience greater

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Colonial spiders evolved a differential prey-capture behaviour in concert with their venom chemistry, which may be a source of novel drugs. Some highly active tetrahydro-beta-carboline (TH beta C) toxins were recently isolated from the venom of the colonial spider Parawixia bistriata; the spiders use these toxins as part of their chemical arsenal to kill and/or paralyze preys. The major TH beta C compound isolated from this venom was identified as 6-hydroxytrypargine, also known as PwTX-I. Most natural compounds of animal origin occur in low abundance, and the natural abundance of PwTX-I is insufficient for complete functional characterization. Thus, PwTx-I was synthesized using a Pictet-Spengler condensation strategy, and the stereoisomers of the synthetic toxin were separated by chiral chromatography. The fraction of venom containing a mixture of three natural TH beta C toxins and enantiomers of PwTx-I were analyzed for inhibition of monoamine oxidase (MAO)-A and -B and for toxicity to insects. We reveal that the mixture of the natural TH beta C toxins, as well as the enantiomers of PwTx-I, were non-competitive inhibitors of MAO-A and MAO-B and caused potent paralysis of honeybees. The (-)-PwTX-I enantiomer is 2-fold more potent than the (+)-PwTX-I enantiomer in the assays performed. (C) 2009 Elsevier Ltd. All rights reserved.

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Increasing recognition of cultural influences on career development requires expanded theoretical and practical perspectives. Theories of career development need to explicate views of culture and provide direction for career counseling with clients who are culturally diverse. The Systems Theory Framework (STF) is a theoretical foundation that accounts for systems of influence on people's career development, including individual, social, and environmental/societal contexts. The discussion provides a rationale for systemic approaches in multicultural career counseling and introduces the central theoretical tenets of the STF. Through applications of the STF, career counselors are challenged to expand their roles and levels of intervention in multicultural career counseling.