Many of steel thin wall closed section members are used by automobile industry. The local buckling of these elements that occur under compressive stress remains the main technological problem. To ...improve the performance of the members, the filling the inside of closed section with the low-density foaming material are usually used. In this study, we present the usefulness of axial compression and 3-point bending tests for the composite members filled with two kinds of epoxy resin. The difference between composite member and thin-walled member was investigated concerning their elastic and plastic collapse characteristics while tested with various deformation velocities. The adherent strength between thin-walled member and foaming material, and filling effect of the foaming material in the energy absorption characteristics was clarified.
A new fabrication method for Si single-electron transistors (SETs) is proposed. The method applies thermal oxidation to a Si wire with a fine trench across it on a silicon-on-insulator substrate. ...During the oxidation, the Si wire with the fine trench is converted, in a self-organized manner, into a twin SET structure with two single-electron islands, one along each edge of the trench, due to position-dependent oxidation-rate modulation caused by stress accumulation. Test devices demonstrated, at 40 K, that the twin SET structure can operate as two individual SET's. Since the present method produces two SET's at the same time in a tiny area, it is suitable for integrating logic circuits based on pass-transistor type logic and CMOS-type logic, which promises to lead to the fabrication of single-electron logic LSIs.
Quantitative measurement of hepatic perfusion has the potential to provide important information in the assessment and management of various liver diseases. The utility of hepatic perfusion ...characterization relies on the resolution of each component of its dual blood supply, i.e. the hepatic artery and portal vein. In this study, a linear equation was derived by integrating the differential equation describing the kinetic behaviour of contrast agent (CA) in a dual-input single-compartment model, from which the kinetic parameters can be easily obtained using the linear least-squares method. The usefulness of this method was investigated using computer simulations, in comparison with the non-linear least-squares (NLSQ) method. This method calculated the kinetic parameters faster than the NLSQ method by a factor of approximately 10, with almost the same accuracy as the NLSQ method. This method will be useful for analysing the kinetic behaviour of CA in the unique liver environment, especially by generating the functional images of kinetic parameters.
The purpose of this study was to evaluate the clinical efficacy of flexible noise control (FNC) image processing in off-line computed radiography (CR) portal images. An observer study was designed to ...compare FNC with multiobjective frequency processing (MFP) in images acquired using a CR portal imaging device (CRPID). The image processing of MFP and FNC used the same data and required no additional irradiation of patients, and all images were printed on 10-bit grey-level dry laser film. Four radiation technologists and one oncologist served as observers and evaluated 40 sets of images for three different treatment sites: brain, lung and pelvis. Six to 10 anatomical landmarks were selected from each treatment site. Each observer was asked to rate each landmark in terms of its clinical visibility and rate the ease of making the pertinent verification in the MFP- and FNC-processed images. In the ratings of the visibility of landmarks and for the verification of treatment ports, FNC-processed images were more visible than MFP-processed images except for several landmarks in the anteroposterior (AP) pelvis such as the pubic symphysis. The visibility of landmarks in FNC-processed images was comparable with that in MFP-processed images. The verification of treatment ports using the CRPID with FNC was generally achievable. In conclusion, this study suggests that FNC is effective for image processing of CR portal images.
Summary
Background : There is currently no optimal second‐line treatment after failure of Helicobacter pylori triple therapy.
Aim : To determine effective salvage therapy after failure of ...lansoprazole–amoxicillin–clarithromycin.
Methods : After failure of lansoprazole–amoxicillin–clarithromycin 123 out‐patients were randomized to receive either 2‐week rabeprazole (20 mg b.d.) + amoxicillin (1000 mg b.d.) (RA group) or 1‐week rabeprazole (10 mg b.d.) + amoxicillin (750 mg twice b.d.) + metronidazole (250 mg b.d.) (RAM group). Eradication was assessed by the 13C‐urea breath test. We also evaluated cytochrome p450 (CYP) 2C19 genotype status, determined by polymerase chain reaction – restriction fragment length polymorphism, and susceptibility to clarithromycin and metronidazole.
Results : On an intention‐to‐treat basis, H. pylori infection cure was achieved in 37 of 63 (59%) patients in the RA group and in 49 of 60 (82%) patients in the RAM group. Per protocol‐based eradication rates in the RA and RAM groups were 66% (37/56) and 88% (49/56), respectively. In both analytic sets there were significant differences between the treatment groups (P < 0.01 in each). Mild adverse events were observed in eight and five patients from the RA and RAM groups, respectively. Genetic predisposition of CYP2C19 and antibiotic resistance did not influence the treatment outcome either regimen.
Conclusions : The rabeprazole + amoxicillin + metronidazole therapy yielded satisfactory results. In contrast, the cure rate in high‐dose rabeprazole + amoxicillin was below an acceptable level.
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•Microspheres loaded with indole derivative were prepared successfully by electrospray.•The drug release from the microspheres depends on the potential formation of hydrogen bonds ...between the drug and the polymer.•A high antiproliferative activity was obtained for the microspheres loaded with aromatic substituents in the indole group.•Differential antiproliferative effect was found between cancer and immortalized cells.
Electrospraying of poly(butylene succinate) and its mixture with different indole derivatives was successfully performed using chloroform as solvent and relatively low flow rates and concentrations. Morphology of particles (size, diameter distribution and surface texture) and encapsulation efficiency were dependent on the loaded drug and specifically on the type of substituent (methyl or phenyl) and its position in the indole core. In general, particles showed a raisin-like morphology caused by the shell collapsing of the resulting structurally weak microspheres. Accumulation of electrosprayed particles gave rise to consistent mats and they had a more hydrophobic surface than that determined for smooth films. The increase of hydrophobicity was mainly dependent on the porosity and the hydrophobic nature of the incorporated drugs. Indole derivatives were hardly delivered in a standard phosphate saline buffer due to their scarce solubility in aqueous media but the addition of ethanol caused a drastic change in the release behavior. This was generally characterized by a fast burst effect and followed by the establishment of an equilibrium condition that was dependent on the indole derivative. However, a clearly different behavior was found when the indole was unable to form hydrogen bonds (e.g. 1-methylindole) since in this case a slow and sustained release was characteristic. Microspheres loaded with indole derivatives showed a high antiproliferative activity that was dependent on encapsulation efficiency and the type of loaded drug. The best results were specifically attained for the indole with an aromatic substituent. Interestingly significant differences were found between cancer and immortalized cells, a feature that points out the potential use of such systems for cancer prevention and treatment.
Hybrid copolymers constituted by short l‐phenylalanine (Phe) blocks (i.e., Phen with n ranging from 2 to 25) and l‐lactide blocks of different length are synthesized and characterized. The diblock ...structure is obtained by ring opening polymerization of lactide using a Phe‐oligopeptide as macroinitiator. The length of the poly(l‐lactide) (PLLA) block is controlled through the lactide/macroinitiator ratio. Morphologic studies of such hybrid copolymers indicate that the assembly of PLLA can be controlled by introducing short Phe blocks. Spherulites with both positive and negative birefringence are achieved in melt crystallization as a consequence of different lamellar distributions. Instead, a high variety of structures are detected in solution‐crystallized samples. Specifically, lozenge single crystals, flower‐like crystals, fibrillar structures, compact spheres, ringed sperulites, dendritic structures, microfibers, and braid‐like microstructures are observed. Some of the detected morphologies are characteristic of self‐assembled Phe‐oligopeptides, suggesting that Phe‐blocks play a crucial role in the self‐assembly properties.
Hybrid copolymers constituted by short l‐phenylalanine blocks and l‐lactide blocks of different length are obtained by ring opening polymerization of lactide using a oligopeptide of phenylalanine as macroinitiator. Hierarchical self‐assembly can be controlled through the copolymer architecture, being possible to get a great morphological variability by a simple modification of the peptide/polylactide ratio.
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