11 research outputs found

    Porous matrixes based on ion-irradiated polymer as templates for synthesis of nanowires

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    Irradiation with swift heavy ions is usually used for production of track membranes (nuclear filters). These membranes traditionally used as filters for fine filtration in medicine and biology. Another application is matrixes for so called matrix synthesis. The idea of this technique is to fill pores by any desired material- metal,polymer, semiconductor and so on. This work is devoted to formation of membrane for template synthesis, to investigation of filling process and to study some properties of obtained structures. It was found that filtration track membranes are not the best material for template synthesis –another type of matrixes are needed- with different pores profiles and parallel pores orientation These parameters could be obtained during irradiation. Different types of etching gave possibility to vary by will the shape of the pores and to obtain pores with conical shape. The process of etching in the alkali solution in mixture of water and alcohol was investigated. The main part of the work devoted to fabrication of micro- and nanowires via electrodeposition. Different types of metals-copper, silver, cobalt and nickel were used for galvanic deposition of the pores. Two types of the processes- galvanostatic and potentiostatic were investigated. It was also demonstrated that obtained metallic nanowires could be used as the substrates for deposition of the probe (biological molecules) in mass-spectrometer. The application of such structures in non-linear optic was also described. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2083

    Unusual Tumors Involving the Head and Neck Region

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    Histoplasma endocarditis: clinical and mycologic features and outcomes

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    Objectives: To define the salient clinical and microbiologic characteristics and outcome of infective endocarditis caused by Histoplasma capsulatum.Methods: Case report and review of 43 literature cases.Results: Infection involved both native (36 cases) and prosthetic (7) heart valves, had a high rate of systemic embolization (58%), and a more delayed diagnosis than bacterial endocarditis. Cardiac involvement generally occurred on mitral and/or aortic valves, and almost always in the setting of disseminated disease. Antemortem diagnosis was best made by serology (serum antibody titers or urinary antigen) or culture of blood (positive in \u3c20% of cases), bone marrow, excised valves, and other non-blood specimens. Other diagnostic methods included histopathology and immunofluorescent staining of tissue samples. Untreated infection was uniformly fatal. Prolonged antifungal therapy with amphotericin B, without surgical intervention, appeared more effective than for Candida endocarditis.CONCLUSIONS: Histoplasma endocarditis is an infrequent but important cause of left-sided, blood culture-negative endocarditis. Its true prevalence may be underestimated because of the relative difficulty in making a precise microbiologic diagnosis. Amphotericin B therapy appears more effective than for Candida endocarditis, while the role for azole treatment and secondary prophylaxis remains uncertain. Indications for surgical valve replacement are similar to those for bacterial endocarditis

    Acoustic eigenmode analysis for ducted inhomogeneous mean flow

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    Effect of maternal intravenous glucose administration on fetal heart rate patterns and fetal breathing.

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    This study was undertaken to evaluate the effect of maternal intravenous (IV) administration of glucose on fetal breathing and its associated fetal heart patterns. Sixteen healthy women at term gestation participated in the study. The outcome of each of the pregnancies was normal. Fetal breathing and fetal electrocardiograms were simultaneously recorded by real time sonography and a fetal monitor respectively, and then digitized into a microcomputer. These women were studied for a 25-minute control period, given 50 gm of glucose IV and then, 20 minutes later, restudied for an additional 25-minute period. The results indicate that fetal breathing movements lasted for 24.8 +/- 6.2 percent of the time during the control period (mean +/- SEM) and were increased to 63.2 +/- 11.5 percent following the injection of glucose (P less than 0.01). Fetal heart rate decreased during fetal breathing by 2.3 and 2.1 beats per minute, before and after glucose administration, respectively (NS). Fetal breathing was associated with increased beat-to-beat variability by 1.32 +/- 0.5 and 1.27 +/- 0.3, before and after glucose administration, respectively (NS). This study confirms previous reports that the amount of time the fetus spends making breathing movements is significantly increased following maternal glucose administration, and demonstrates that the injection of glucose does not alter the modulation of fetal heart rate and beat-to-beat variability by fetal breathing

    Spatial instability of boundary layer along impedance wall

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    In previous work we studied linear and nonlinear left-invariant diffusion equations on the 2D Euclidean motion group SE(2), for the purpose of crossing-preserving coherence-enhancing diffusion on 2D images. In this article we study left-invariant diffusion on the 3D Euclidean motion group SE(3) and its application to crossing-preserving smoothing of high angular resolution diffusion imaging (HARDI), which is a recent magnetic resonance imaging (MRI) technique for imaging water diffusion processes in fibrous tissues such as brain white matter and muscles. The linear left-invariant (convection-)diffusions are forward Kolmogorov equations of Brownian motions on the space R3 o S2 of positions and orientations embedded in SE(3) and can be solved by R3 o S2-convolution with the corresponding Green’s functions. We provide analytic approximation formulae and explicit sharp Gaussian estimates for these Green’s functions. In our design and analysis for appropriate (non-linear) convection-diffusions on HARDI-data we put emphasis on the underlying differential geometry on SE(3). We write our left-invariant diffusions in covariant derivatives on SE(3) using the Cartan-connection. This Cartan-connection has constant curvature and constant torsion, and so have the exponential curves which are the auto-parallels along which our left-invariant diffusion takes place. We provide experiments of our crossing-preserving Euclidean-invariant diffusions on artificial HARDI-data containing crossing-fibers
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