993 resultados para 207-1258C
Resumo:
An adaptive drug delivery design is presented in this paper using neural networks for effective treatment of infectious diseases. The generic mathematical model used describes the coupled evolution of concentration of pathogens, plasma cells, antibodies and a numerical value that indicates the relative characteristic of a damaged organ due to the disease under the influence of external drugs. From a system theoretic point of view, the external drugs can be interpreted as control inputs, which can be designed based on control theoretic concepts. In this study, assuming a set of nominal parameters in the mathematical model, first a nonlinear controller (drug administration) is designed based on the principle of dynamic inversion. This nominal drug administration plan was found to be effective in curing "nominal model patients" (patients whose immunological dynamics conform to the mathematical model used for the control design exactly. However, it was found to be ineffective in curing "realistic model patients" (patients whose immunological dynamics may have off-nominal parameter values and possibly unwanted inputs) in general. Hence, to make the drug delivery dosage design more effective for realistic model patients, a model-following adaptive control design is carried out next by taking the help of neural networks, that are trained online. Simulation studies indicate that the adaptive controller proposed in this paper holds promise in killing the invading pathogens and healing the damaged organ even in the presence of parameter uncertainties and continued pathogen attack. Note that the computational requirements for computing the control are very minimal and all associated computations (including the training of neural networks) can be carried out online. However it assumes that the required diagnosis process can be carried out at a sufficient faster rate so that all the states are available for control computation.
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The coupled wavenumbers of a fluid-filled flexible cylindrical shell vibrating in the axisymmetric mode are studied. The coupled dispersion equation of the system is rewritten in the form of the uncoupled dispersion equation of the structure and the acoustic fluid, with an added fluid-loading term involving a parameter e due to the coupling. Using the smallness of Poisson's ratio (v), a double-asymptotic expansion involving e and v 2 is substituted in this equation. Analytical expressions are derived for the coupled wavenumbers (for large and small values of E). Different asymptotic expansions are used for different frequency ranges with continuous transitions occurring between them. The wavenumber solutions are continuously tracked as e varies from small to large values. A general trend observed is that a given wavenumber branch transits from a rigidwalled solution to a pressure-release solution with increasing E. Also, it is found that at any frequency where two wavenumbers intersect in the uncoupled analysis, there is no more an intersection in the coupled case, but a gap is created at that frequency. Only the axisymmetric mode is considered. However, the method can be extended to the higher order modes.
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The importance of seepage in the design of channels is discussed. Experimental investigations reveal that seepage, either in the downward direction (suction) or in the upward direction (injection), can significantly change the resistance as well as the mobility of the sand-bed particles. A resistance equation relating 'particle Reynolds number' and 'shear Reynolds number' under seepage conditions is developed for plane sediment beds. Finally, a detailed design procedure of the plane sediment beds affected by seepage is presented.
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An HIV outbreak among Finnish injecting drug users (IDUs) occurred in 1998. By the end of 2005, 282 IDUs were in-fected, most of them by recombinant virus CRF01_AE of HIV. After a rapid spread, the outbreak subsided, and the prevalence of HIV among IDUs remained low (<2%). The purpose of the study was to describe the outbreak in order to recognise factors that have influenced the spread and restriction of the outbreak, and thus to find tools for HIV preven-tion. Data on Finnish IDUs newly diagnosed HIV-positive between 1998 and 2005 was collected through interviews and patient documents. Study I compared markers of disease progression between 93 Finnish IDUs and 63 Dutch IDUs. In study II, geographical spread of the HIV outbreak was examined and compared with the spatial distribution of employed males. In study III, risk behaviour data from interviews of 89 HIV-positive and 207 HIV-negative IDUs was linked, and prevalence and risk factors for unprotected sex were evaluated. In study IV, data on 238 newly diagnosed IDUs was combined with data on 675 sexually transmitted HIV cases, and risk factors for late HIV diagnosis (CD4 cell count <200/µL, or AIDS at HIV diagnosis) were analysed. Finnish IDUs infected with CRF01_AE exhibited higher viral loads than did Amsterdam IDUs infected with subtype B, but there was no difference in CD4 development. The Finnish IDU outbreak spread and was restricted socially in a marginalised IDU population and geographically in areas characterised by low proportions of employed males. Up to 40% of the cases in the two clusters outside the city centre had no contact with the centre, where needle exchange services were available since 1997. Up to 63% of HIV-positive and 80% of HIV-negative sexually active IDUs reported inconsistent condom use, which was associated with steady relationships and recent inpatient addiction care. Com-pared to other transmission groups, HIV-positive IDUs were diagnosed earlier in their infection. The proportion of late diagnosed HIV cases in all transmission groups was 23%, but was only 6% among IDUs diagnosed during the first four years of the epidemic. The high viral load in early HIV infection may have contributed to the rapid spread of recombinant virus in the Finnish outbreak. The outbreak was restricted to a marginalised IDU population, and limited spatially to local pockets of pov-erty. To prevent HIV among IDUs, these pockets should be recognised and reached early through outreach work and the distribution of needle exchange and other prevention activities. To prevent the sexual transmission of HIV among IDUs, prevention programmes should be combined with addiction care services and targeted at every IDU. The early detection of the outbreak and early implementation of needle exchange programmes likely played a crucial role in re-versing the IDU outbreak.
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α-Manganese dioxide is synthesized in a microemulsion medium by a redox reaction between KMnO4 and MnSO4 in presence of sodium dodecyl sulphate as a surface active agent. The morphology of MnO2 resembles nanopetals, which are spread parallel to the field. The material is further characterized by powder X-ray diffraction, energy dispersive analysis of X-ray, and Brunauer–Emmett–Teller surface area. Supercapacitance property of α-MnO2 nanopetals is studied by cyclic voltammetry and galvanostatic charge–discharge cycling. High values of specific capacitance are obtained.
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The enantioselective syntheses of diquinane and cis, anti, cis-linear triquinanes, starting from the readily available (S)-campholenaldehyde, employing an intramolecular rhodium carbenoid CH insertion reaction, are described. (C) 2010 Elsevier Ltd. All rights reserved.
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This paper considers the dynamic modelling and motion control of a Surface Effect Ship (SES) for safer transfer of personnel and equipment from vessel to-and-from an offshore wind-turbine. The control system designed is referred to as Boarding Control System (BCS). The performance of this system is investigated for a specific wind-farm service vessel—The Wave Craft. On a SES, the pressurized air cushion supports the majority of the weight of the vessel. The control problem considered relates to the actuation of the pressure such that wave-induced vessel motions are minimized. Results are given through simulation, model- and full-scale experimental testing.
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Purpose: Testis specific heat-shock protein 70-2 (HSP70-2), a member of HSP70 chaperone family, is essential for the growth of spermatocytes and cancer cells. We investigated the association of HSP70-2 expression with clinical behaviour and progression of urothelial carcinoma of bladder. Experimental design: We assessed the HSP70-2 expression by RT-PCR and HSP70-2 protein expression by immunofluorescence, flow cytometry, immunohistochemistry and Western blotting in urothelial carcinoma patient specimens and HTB-1, UMUC-3, HTB-9, HTB-2 and normal human urothelial cell lines. Further, to investigate the role of HSP70-2 in bladder tumour development, HSP70-2 was silenced in the high-grade invasive HTB-1 and UMUC-3 cells. The malignant properties of urothelial carcinoma cells were examined using colony formation, migration assay, invasion assay in vitro and tumour growth in vivo. Results: Our RT-PCR analysis and immunohistochemistry analysis revealed that HSP70-2 was expressed in both moderate to well-differentiated and high-grade invasive urothelial carcinoma cell lines studied and not in normal human urothelial cells. In consistence with these results, HSP70-2 expression was also observed in superficially invasive (70%) and muscle-invasive (90%) patient's tumours. Furthermore, HSP70-2 knockdown significantly suppressed cellular motility and invasion ability. An in vivo xenograft study showed that inhibition of HSP70-2 significantly suppressed tumour growth. Conclusions: In conclusion, our data suggest that the HSP70-2 expression is associated with early spread and progression of urothelial carcinoma of bladder cancer and that HSP70-2 can be the potential therapeutic target for bladder urothelial carcinoma. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
The goals of this study were to analyze the forms of emotional tendencies that are likely to motivate moral behaviors, and to find correlates for these tendencies. In study 1, students narratives of their own guilt or shame experiences were analyzed. The results showed that pure shame was more likely to motivate avoidance than reparation, whereas guilt and combination of guilt and shame were likely to motivate reparation. However, all types of emotion could lead to chronic rumination if the person was not clearly responsible for the situation. In study 2, the relations of empathy with two measures of guilt were examined in a sample of 13- to 16-year-olds (N=113). Empathy was measured using Davis s IRI and guilt by Tangney s TOSCA and Hoffman s semi-projective story completion method that includes two different scenarios, guilt over cheating and guilt over inaction. Empathy correlated more strongly with both measures of guilt than the two measures correlated with each other. Hoffman s guilt over inaction was more strongly associated with empathy measures in girls than in boys, whereas for guilt over cheating the pattern was the opposite. Girls and boys who describe themselves as empathetic may emphasize different aspect of morality and feel guilty in different contexts. In study 3, cultural and gender differences in guilt and shame (TOSCA) and value priorities (the Schwartz Value Survey) were studied in samples of Finnish (N=156) and Peruvian (N=159) adolescents. Gender differences were found to be larger and more stereotypical among the Finns than among the Peruvians. Finnish girls were more prone to guilt and shame than boys were, whereas among the Peruvians there was no gender difference in guilt, and boys were more shame-prone than girls. The results support the view that psychological gender differences are largest individualistic societies. In study 4, the relations of value priorities to guilt, shame and empathy were examined in two samples, one of 15 19-year-old high school students (N = 207), and the other of military conscripts (N = 503). Guilt was, in both samples, positively related to valuing universalism, benevolence, tradition, and conformity, and negatively related to valuing power, hedonism, stimulation, and self-direction. The results for empathy were similar, but the relation to the openness conservation value dimension was weaker. Shame and personal distress were weakly related to values. In sum, shame without guilt and the TOSCA shame scale are tendencies that are unlikely to motivate moral behavior in Finnish cultural context. Guilt is likely to be connected to positive social behaviors, but excessive guilt can cause psychological problems. Moral emotional tendencies are related to culture, cultural conceptions of gender and to individual value priorities.
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A ligand series obtained from V = O stretching frequencies for different monomeric complexes of oxovanadium(IV) is shown to parallel the nephelauxetic series. The ligand series obtained from streching frequencies of other systems are also shown to compare well with the nephelauxetic series rather than the spectrochemical series.
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The dipole moment of chloral hydrate is 2·07 D and 2·65 D at 35° in benzene and dioxane solutions respectively. Bromal hydrate has a moment of 2·56 D in benzene solution. The moments observed can reasonably be accounted for on the scheme of Smith et al. and the results have been discussed in terms of the possible structures of these molecules.
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The concept of a fully-developed flow based on the hypothesis of selective memory is here applied to general wall-jet type flows. In the presence of a (constant) external stream, the free-stream velocity and the jet momentum flux are taken to be the chief quantities governing the development of the wall jet: two additional nondimensional parameters, representing a momentum flux Reynolds number and the relative momentum defect in the initial boundary layer, are shown to have only a secondary effect on the fully-developed flow. The standard correlations so determined are also found to predict quite well the flow development in Gartshore and Newman's experiments on wall jets in adverse pressure gradients; possible reasons for this somewhat surprising result are discussed. Finally it is shown, by application to the still-air case, that the parameters discovered in incompressible flow are, with appropriate but straightforward modification, successful in describing compressible wall jets also.
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BacilliformOryctes baculovirus particles have been visualized in electron micrographs of midgut sections from virus infectedOryctes rhinoceros beetles. Morphologically the Indian isolate (Oryctes baculovirus, KI) resembled the previously reportedOryctes baculovirus, isolate PV505. The constituent proteins of baculovirus KI have been analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and by Western blots using polyclonal antibodies raised against the complete viral particles, as probes. A total of forty eight viral proteins have been identified. Fourteen viral proteins were located on the viral envelope. Among the proteins constituting the nucleocapsid, three were located internally within the capsid. A 23.5 kDa protein was tightly associated with viral DNA in the nucleocapsid core. Two envelope and seven capsid proteins stained positive for glycosylation. Comparison between the viral proteins of KI and PV505 revealed differences in SDS-PAGE profiles and glycosylation patterns. Immunoblotting of KI and PV505 proteins with anti KI antiserum demonstrated antigenic differences between the two viral isolates.
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ANNE HOLMA ADAPTATION IN TRIADIC BUSINESS RELATIONSHIP SETTINGS – A STUDY IN CORPORATE TRAVEL MANAGEMENT Business-to-business relationships form complicated networks that function in an increasingly dynamic business environment. This study addresses the complexity of business relationships, both when it comes to the core phenomenon under investigation, adaptation, and the structural context of the research, a triadic relationship setting. In business research, adaptation is generally regarded as a dyadic phenomenon, even though it is well recognised that dyads do not exist isolated from the wider network. The triadic approach to business relationships is especially relevant in cases where an intermediary is involved, and where all three actors are directly connected with each other. However, only a few business studies apply the triadic approach. In this study, the three dyadic relationships in triadic relationship settings are investigated in the context of the other two dyads to which each is connected. The focus is on the triads as such, and on the connections between its actors. Theoretically, the study takes its stand in relationship marketing. The study integrates theories and concepts from two approaches, the industrial network approach by the Industrial marketing and purchasing group, and the Service marketing and management approach by the Nordic School. Sociological theories are used to understand the triadic relationship setting. The empirical context of the study is corporate travel management. The study is a retrospective case study, where the data is collected by in-depth interviews with key informants from an industrial enterprise and its travel agency and service supplier partners. The main theoretical contribution of the study concerns opening a new research area in relationship marketing by investigating adaptation in business relationships with a new perspective, and in a new context. This study provides a comprehensive framework to analyse adaptation in triadic business relationship settings. The analysis framework was created with the help of a systematic combining approach, which is based on abductive logic and continuous iteration between the theory and the case study results. The framework describes how adaptations initiate, and how they progress. The framework also takes into account how adaptations spread in triadic relationship settings, i.e. how adaptations attain all three actors of the triad. Furthermore, the framework helps to investigate the outcomes of the adaptations for individual firms, for dyadic relationships, and for the triads. The study also provides concepts and classification that can be used when evaluating adaptation and relationship development in both dyadic and triadic relationships.