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A position-sensitive pixel array silicon detector with a junction field effect transistor (JFET) switch structure is studied as a device for the direct illumination of X-ray from synchrotron light source. Considering an absorption length of silicon at an X-ray energy and a required thickness of a silicon, a 525 μ m n-type silicon wafer with high resistivity is chosen as the active volume of the detector and is depleted by applying a negative bias voltage to the junction side. The electron–hole pairs produced in an active volume by an X-ray illumination are collected on the electrodes . All pixels with one row are read in parallel and the next row is selected by the control voltage after one row has finished being read. The field shaper is introduced to produce inter-pixel isolation. We perform the simulation of the pixelated silicon position detector with JFET switch and present the characteristics of the transistor such as the drain current as a function of the voltage between the source and drain for different gate voltages. The fabrication processes of the pixel sensor with JFET switch structure based on the simulation result are also described.

Illegal dumping refers to the unauthorised disposal of waste in public or private land, which impacts on the surrounding environment. In literature, many studies on minor offences focused on qualitative methods such as questionnaire surveys, of which the findings might be confined to social expectation bias, small sample size, questionnaire design and limited applicability. This study aims at understanding illegal dumping behaviour records in the big picture of urban big data from multiple sources, including demography, geography, economy, and household. We georeferenced the penalty records from January 2014 to June 2019 in Hong Kong and connected them to other data sources. We found that old urban areas were more prone to fly-tipping of building debris and half of the districts most stricken with fly-tipping of waste predominantly comprising renovation waste had a higher proportion of population residing in owner-occupied properties. The levels of income and education were found to have no direct impact on the tendency to commit illegal dumping behaviours. The findings in this paper, therefore, provide directions for the government in formulating policies to fight against illegal dumping.

Chitosan-based composite films with different amounts of grapefruit seed extract (GFSE) (0.5, 1.0 and 1.5% v/v) were fabricated via solution casting technique. Experimental results showed that GFSE was uniformly dispersed within all chitosan film matrices. The presence of GFSE made the films more amorphous and tensile strength decreased, while elongation at break values increased as GFSE content increased. Results from the measurement of light transmission revealed that increasing amounts of GFSE (from 0.5 to 1.5% v/v) did not affect transparency of the films. Furthermore, packaging of bread samples with chitosan-based GFSE composite films inhibited the proliferation of fungal growth as compared to control samples. Hence, chitosan-based GFSE composite films have the potential to be a useful material in the area of food technology.

We develop the compact NMR/MRI device using high temperature superconducting (HTS) wires with the persistent current mode operating. So, the joint techniques between 2G wires are very important issue and many studies have been carried out. Recently, the K JOINS, Inc. has developed successfully the high performance superconducting joints between 2G wires by partial melting diffusion and oxygenation annealing process [1]. In this study, the current bypassing properties in a loop-shaped 2G wire are measured experimentally to develop the permanent current switch (PSC). The current bypassing properties of loop-shaped test coil wound with 2G wire (GdBCO) are evaluated by measured the self-magnetic field due to bypassed current by Hall sensors. The strain gauge was used as heater for persistent current switch, and thermal properties against various thermal inputs were investigated experimentally.

s: Parallel imaging technique can provide several advantages for a multitude of MRI applications. Especially,in SENSE technique, sensitivity maps were always required in order to determine the reconstruction matrix, there-fore, a number of difference approaches using sensitivity information from coils have been demonstrated to improveof image quality. Moreover, many filtering methods were proposed such as adaptive matched filter and nonlinear dif-fusion technique to optimize the suppression of background noise and to improve of image quality. In this study, weperformed SENSE reconstruction using computer simulations to confirm the most suitable method for the feasibilityof filtering effect and according to changing order of polynomial fit that were applied on variation of spatial resolutionof sensitivity map. The image was obtained at 0.32T(Magfinder II, Genpia, Korea) MRI system using spin-echo pulsesequence(TR/TE = 500/20 ms, FOV = 300 mm, matrix = 128×128, thickness = 8 mm). For the simulation, obtainedimage was multiplied with four linear-array coil sensitivities which were formed of 2D-gaussian distribution and theimage was complex white gaussian noise was added. Image processing was separated to apply two methods whichwere polynomial fitting and filtering according to spatial resolution of sensitivity map and each coil image was sub-sampled corresponding to reduction factor(r-factor) of 2 and 4. The results were compared to mean value of geometyfactor(g-factor) and artifact power(AP) according to r-factor 2 and 4. Our results were represented while changingof spatial resolution of sensitivity map and r-factor, polynomial fit methods were represented the better results com-pared with general filtering methods. Although our result had limitation of computer simulation study instead ofapplying to experiment and coil geometric array such as linear, our method may be useful for determination of optimalsensitivity map in a linear coil array.Key words: SENSE, sensitivity map, polynomial fitting, low pass filtering, spatial resolution

Umbilical cord blood (UCB)-derived mesenchymal stem cells (MSC) facilitate the engraftment of human (h) hematopoietic stem cells when transplanted simultaneously in animal and human studies. However, the type of MSCs that preferentially enhance the engraftment of HSCs is unknown. Recent studies have shown that MSCs derived from a single source are heterogeneous in terms of cell size, morphology, proliferation rate, and differentiation potential. This study was designed to investigate the properties of UCB-MSCs, which influence the engraftment of hHSCs in a NOD/SCID mouse model. We categorized MSCs as being the most effective (UCB-352 MSCs) or the least effective (UCB-156 MSCs) at promoting the homing and engraftment of HSCs, and compared the characteristics of these 2 MSC populations. We observed that the 2 populations showed differences in characteristics typical of immature MSCs, and related to proliferation potential. We showed that UCB-352 MSCs, which proliferate quickly, preferentially enhanced the engraftment of HSCs in NOD/SCID mice. In addition, we observed differences in the pattern of both PODXL and Oct4 expression, and in the levels of cytokines such as SDF-1 and SCF using flow cytometry and membrane arrays. The more effective UCB-352 MSCs expressed higher levels of PODXL and Oct4, which were associated with immaturity, than did the UCB-156 MSCs. Furthermore, UCB-352 cells secreted greater levels of SDF-1 and SCF, both of which are required for hematopoiesis. We propose that the proliferation potential of UCB-MSCs, coupled with their immature characteristics, may serve as a novel standard to promote the homing and engraftment of HSCs.

Umbilical cord blood (UCB), a rich source of hematopoietic stem cells, offers practical and ethical advantages. It has been reported that various adult stem cells transplanted into a damaged liver show characteristics of a hepatic lineage. In a previous study, we reported on novel UCB-derived adult stem cells, termed umbilical cord blood-derived multipotent progenitor cells (UCB-MPCs). We demonstrated that these cells were capable of differentiating into hepatocyte- like cells in vitro. To assess the hepatic differentiation capacity of UCB-MPCs, rat models of hepatic injury were generated using carbon tetra-chloride (CCl 4 ) with transplantation of cells into the liver. The transplanted cells successfully incorporated into the liver of the recipient animal differentiated into functional hepatocyte-like cells that expressed hepatocyte-specific markers, such as CK-18 and albumin. Moreover, human albumin was detected in the serum of the recipient rat model. These data indicated that UCB-MPCs were capable of displaying similar characteristics to those of functional hepatocytes in a recipient liver. UCB-MPCs may prove to be a useful, transplantable alternative for hepatic progenitor cells in both experimental and therapeutic applications.

Thermal energy control is a important factor to control properties of large sized product in ingot-forging. Good control of thermal energy helps to increase characteristics and eliminate defects of large cast-forged part, such as large sized forged shell. We have studied about not only large size ring forging process and after heat treatment process by FEM simulation. Changes of temperature and microstructure for forged shell were predicted according to different heat treatment conditions. Therefore, we can choose the proper heat treatment condition by FEA. The sectional properties confirmed by practical experiment and evaluation have presented possibilities of process design by computational analysis.

Disseminated microsporidiosis is diagnosed uncommonly in patients not infected with human immunodeficiency virus (HIV). We present a case of disseminated microsporidiosis in a renal transplant recipient who was seronegative for HIV. Chromotrope-based stains were positive for microsporidia in urine, stools, sputum, and conjunctival scrapings. Electron microscopy, immunofluorescence, polymerase chain reaction, and cultures of renal tissue identified the organism as Encephalitozoon cuniculi. The patient was treated with oral albendazole and topical fumagillin with clinical improvement. In addition, she underwent a transplant nephrectomy and immunosuppressive therapy was withdrawn. Follow-up samples were negative for microsporidia. However, the patient developed central nervous system manifestations and died. An autopsy brain tissue specimen demonstrated E. cuniculi by immunofluorescent staining. Disseminated microsporidiosis must be considered in the differential diagnosis of multiorgan involvement in renal allograft recipients.

Background and Purpose— Experimental evidence has indicated the benefits of simvastatin for the treatment of subarachnoid hemorrhage. Two randomized placebo-controlled pilot trials that used the highest clinically approved dose of simvastatin (80 mg daily) gave positive results despite the fact that a lower dose of simvastatin (40 mg daily) did not improve clinical outcomes. We hypothesized that a high dose of 80 mg of simvastatin daily for 3 weeks would reduce the incidence of delayed ischemic deficits after subarachnoid hemorrhage compared with a lower dose (40 mg of simvastatin daily) and lead to improved clinical outcomes. Methods— The study design was a randomized controlled double-blinded clinical trial. Patients with aneurysmal subarachnoid hemorrhage (presenting within 96 hours of the ictus) from 6 neurosurgical centers were recruited for 3 years. The primary outcome measure was the presence of delayed ischemic deficits, and secondary outcome measures included a modified Rankin disability score at 3 months and an analysis of cost-effectiveness. Results— No difference was observed between the groups treated with the higher dose or the lower dose of simvastatin in the incidence of delayed ischemic deficits (27% versus 24%; odds ratio, 1.2; 95% confidence interval, 0.7–2.0; P =0.586) or in the rate of favorable outcomes (modified Rankin Scale score, 0–2) at 3 months (73% versus 72%; odds ratio, 1.1; 95% confidence interval, 0.6–1.9; P =0.770). Conclusions— High-dose simvastatin treatment should not be prescribed routinely for aneurysmal subarachnoid hemorrhage. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01077206.

We report that it was successful to use thermal and UV embossing techniques for the fabrication of 1310/1550nm directional coupler demultiplexer and 1x4 MMI optical power splitter, respectively. The mold was prepared with a poly-dimethylsiloxane (PDMS) elastomer, and the pattern was transferred from the photoresist. We experimented also on the durability of the PDMS mold and successfully fabricated 50th replica with thermal curable polymer and 17th replica with UV curable polymer, respectively.

In this study, it was attempted to construct damage assessment model which could systematically analyze and predict the effects on the semiconductor devices. At first, the PIN diode was designed and manufactured for both the simulation and radiation test. After that the radiation test were performed to it with Gamma-ray. Next, after inputting the pulse model similar to that used in the measurement into 3D model PIN diode with the same parameters of the process design, the behavior of the instantaneous charges which were generated inside the devices were analyzed and the output current value was simulated. The results obtained from the two processes showed the similar characteristics

Far infrared measurements on detwinned single crystals at 2 K give an anisotropic absorptivity for the a and b polarizations. A ≊ 0.5% for the axis from ≊ 100cm −1 up to the optical edge at 400cm −1 . The a axis conductivity shows low frequency absorption bands of electronic strength.

Sternal dehiscence and mediastinitis are two of the most severe complications of a median sternotomy. A technique of closure is described that appears to provide a more stable sternal approximation without any increase in overall complication rate. Using this technique in 978 consecutive patients, no cases of sternal dehiscence or mediastinitis have been seen.