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The Particle Detector (PD) experiment aboard the geostationary satellite GEO-KOMPSAT-2A (GK2A) measures populations of electrons and positive ions in the Earth’s geostationary orbit at a geographic longitude of $128.2^{\circ }\mbox{E}$, inclination of $0^{\circ }$ and a mean orbital radius of 6.6 Earth radii ($R_{E}$). The PD experiment consists of three sensors with different viewing angles relative to the spacecraft. Each sensor consists of two telescopes that are mechanically configured back-to-back with a field-of-view of $20^{\circ }\times 20^{\circ }$ and measures electrons and ions, using silicon detectors equipped with foils and magnets for the separation of ions and electrons. The energy ranges of the sensor for electrons and ions are 100–3800 keV and 148–22500 keV, respectively. A particular emphasis on electron measurement is given by allocating 48 energy bins in the measured energy range, whereas 22 energy bins are allocated for ion measurements. This unprecedented energy resolution of $\Delta E/E$ in the range 5–25% for the electron and ion flux measurements is acquired every three seconds with cyclic polling of each sensor every second to provide an effective temporal resolution of one second. Together with the magnetometer aboard the spacecraft, the PD experiment will provide quantitative observations that will enable improved understanding of the adiabatic and nonadiabatic dynamics of the Earth’s magnetosphere for space weather studies at geostationary orbits from the vantage point of a far-east longitude.

This study aimed to analyze the use of the revised International Prognostic Scoring System (IPSS-R) assessed after hypomethylating treatment (HMT) for patients with myelodysplastic syndrome (MDS) undergoing an allogeneic stem cell transplantation (SCT). Among 115 patients who received pre-SCT HMT, comparison analysis of the prognostic values between the IPSS-R at the time of HMT (IPSS-R@HMT) and at the time of SCT after HMT (IPSS-R@SCT) showed a significantly higher predictive power for overall survival (OS) of the latter. Alteration in IPSS-R risk occurred in 60%, while the patients with 'down-staged' IPSS-R@SCT showed better OS compared with those with 'unchanged' or 'up-staged' risk. On multivariate analysis in all 201 patients, IPSS-R@SCT, monosomal karyotype, treatment failure to pre-SCT treatment, and high hematopoietic cell transplantation-comorbidity index were independently associated with OS. Constructed using these factors, the MDS Transplantation Prognostic Scoring System (MTPSS) identified four risk groups with 4-year OS of 76.4% in low, 61.4% in intermediate-1 and 21.9% in intermediate-2 risk groups, whereas all in the high risk group died within 2 years after SCT (P

Experimental, prospective study.Fecal incontinence and constipation affect the quality of life (QOL) of children with spina bifida and their caregivers. We evaluated the clinical efficacy of a stepwise bowel management program on QOL for children with spina bifida and their caregivers.Republic of Korea.Between December 2010 and April 2011, 53 children with constipation, fecal incontinence or both underwent a stepwise bowel management program at our spina bifida clinic. The children and their caregivers were evaluated before and after this program using a self-administered questionnaire.Among the children, 11.3% received only oral laxatives and controlled well, 88.7% received transanal irrigation. After this program, the mean number of episodes of fecal incontinence per week, number of diaper changes and total time for bowel care decreased from 6.9 to 0.5 (P=0.004), from 1.6 to 0.2 (P=0.001) and from 27 to 15.9 min (P=0.003), respectively. Caregivers and children were able to leave their houses more often (P=0.006), and caregivers' bothersomeness, anxiety and depression due to bowel care decreased (P0.001). Factors related to family relationships (P=0.265) and financial impact (P=0.071) improved, but not significantly.We observed significant improvement in defecation symptoms and QOL scores of spina bifida patients who underwent this program. We recommend that this simple therapeutic method be considered as a safe and valid choice for the treatment of chronic constipation and fecal incontinence.

The Centers for Disease Control and Prevention (CDC) recommend oral or intravenous doxycycline plus a third-generation cephalosporin or fluoroquinolone alone for the treatment of Vibrio vulnificus infections. Until now, no study has compared oral with parenteral administered doxycycline with respect to their in vivo efficacy. In the present work, ICR mice infected with a high dose of V. vulnificus were administered ciprofloxacin, ceftriaxone, and doxycycline. The bacterial DNA copy number in surviving and non-surviving mice was determined using quantitative polymerase chain reaction (qPCR). In this setting, ciprofloxacin was the most effective monotherapeutic drug, but a higher survival rate (50%) was achieved using the combination therapy of intraperitoneal doxycycline plus ceftriaxone. The blood of non-surviving mice at 12 h post-infection contained at least 10(4) DNA copies/μL, in contrast to 10(2) to 10(3) DNA copies/μL in surviving mice. Thus, in the treatment of V. vulnificus infections in humans, when the intravenous form of doxycycline is unavailable, ciprofloxacin might be a better option than oral doxycycline to lower mortality. In addition, our results demonstrate that qPCR can be a useful tool for identifying the V. vulnificus load in infected patients, with the DNA copy number providing a marker of either disease severity or mortality.

In this paper, a method to establish a decision criterion to evaluate the quality of small window motors using sound quality (SQ) metrics is suggested. Although the sound level radiated from the motor is relatively small compared to other sounds in a car, the sound from an abnormal motor gives an uncomfortable feeling and the impression of abnormal operation, which can lead to customer complaints. To construct an objective decision criterion, the correlation between the SQ metrics and the subjective decision on the passing or failure of the motor were investigated. Four representative SQ metrics, viz., loudness, sharpness, roughness, and fluctuation strength, were calculated for the collected samples. It was observed that the loudness and roughness of the motor sample group classified as abnormal was higher than those of the normal motors. For a single figure rating for motor quality, an evaluation index for the motor sound was generated by combining the correlated SQ metrics with proper weightings. Evaluation results on the specimens that were not employed in generating the quality evaluation index showed a reasonable agreement with the subjective test at 73%. The suggested quality check method can replace the current subjective decision procedure to identify the faulty motors.

Highly selective and low damage etching of the GaAs cap layer on AlGaAs is essential in fabricating GaAs/AlGaAs high electron mobility transistors. The GaAs on AlGaAs was etched using a low energy Cl2/O2 neutral beam and the Schottky device characteristics fabricated on the exposed AlGaAs were compared with those fabricated after the etching using wet etching and a Cl2/O2 ion beam. Using a low energy Cl2/O2 ion beam or a Cl2/O2 neutral beam, highly selective etching of the GaAs cap layer to AlGaAs similar to wet etching could be achieved through the formation of Al2O3 on the exposed AlGaAs during the etching. When the electrical characteristics of the Schottky devices were compared, the devices fabricated after the etching using the neutral beam showed the best electrical characteristics such as electrical stability, low leakage current, higher barrier height, etc. by showing low damage to the exposed AlGaAs surface.

This study was undertaken to examine ultrastructural changes induced by dopamine in fish prolactin cells. Tilapia adenohypophyses were incubated with dopamine and evaluated by electron microscopy. The quantities of rough endoplasmic reticulum (RER) in prolactin cells increased and the number of secretory granules were decreased by dopamine (10(-6) mol/l) treatment. Another set of adenohypophysial tissues was placed back into control medium for 10 min following a 3 h incubation period with dopamine (10(-6) mol/l) (RE10 min group). This group had significantly less RER than the 3 h dopamine-treated tissue, and the shape of many granules in the RE10 min group changed from spherical to rod-like. In addition, some of the granule content appeared to diffuse out of granules since some were not fully surrounded by membrane. It was therefore hypothesized that the rod-shaped granules might be the result of prolactin secretion by diffusion.

Measurements of 77K RoA and 300K reverse bias dynamic impedance (RdA) products at one volt reverse bias has been carried out to assess the degree of correlation of this figure of merit. Planar P-on-n heterostructures were grown on near lattice-matched CdZnTe substrates with Hg1-xCdxTe (0.20< x

Extrinsic p-type doping of long wavelength infrared-HgCdTe double layer heterostructure for p-on-n device application requires good control of the p-type dopant, regardless of the doping technique. The approach is to place the electrical junction ahead of the compositional interface, thus avoiding quantum efficiency reduction. This research addresses the As and P doping of HgCdTe by an implant/diffusion process. The data demonstrates an enhanced atomic diffusion process for As and P from an ion implanted source, within the single phase domain, with a diffusion rate orders of magnitude higher than the rate under Hg-saturated conditions at the same temperature. This work also reveals a new phenomenon, namely, a transition in the enhanced diffusion of both As and P from an exponential to a Gaussian redistribution. This transition is controlled by temperature at a given PHg. Gaussian diffusion dominates at high temperatures, T >400°C. The diffusion coefficient of the Gaussian mechanism decreases as the PHg increases, from Dp ~2 x 10-11 cm2/s at PHg ~0.02 atm to Dp ~3 x 10-14 cm2/ s under Hg-saturated conditions (quartz ampoule) at 440°C. The difference in the diffusion coefficients between open tube and closed tube (quartz ampoule), under nominally Hg-saturated conditions, indicates that PHg is undersaturated regardless of the Hg-source proximity. The deviation of PHg from saturation is estimated from the annealing furnace temperature profile up to a maximum of 50%. Variation of the diffusion coefficient close to Hg saturation appears to be sharply dependent on the actual PHg value (example: Dp ~1 x 10-12 cm2/s in open-tube anneal vs Dp ~3 x 10-14 cm2/s in closed tube at nominally the same temperature, T = 440°C). Comparative anneals of As and P showed faster diffusion rates for P than for As in both mechanisms.

Temperature and time dependent Hg-annealing studies for arsenic activation have been carried out on As-doped molecular beam epitaxy HgCdTe eitherin situ or by ion implantation to determine the extent of arsenic activation in the single layer. Enhanced As diffusion and activation in double layer heterostructures have also been investigated to further our understanding of the effects on zero bias resistance-area product (RoA) and quantum efficiency. The results show that the arsenic activation anneal is limited by Hg self-diffusion into the HgCdTe epilayer. Using this arsenic activation process for eitherin situ doped arsenic or implanted arsenic, high performance p-on-n double layer heterostructure photodiodes have been demonstrated on both mesa and planar device structures.

We have carried out a study and identified that MBE HgCdTe growth-induced void defects are detrimental to long wavelength infrared photodiode performance. These defects were induced during nucleation by having surface growth conditions deficient in Hg. Precise control and reproducibility of the CdZnTe surface temperature and beam fluxes are required to minimize such defects. Device quality material with void defect concentration values in the low 102 cm2 range were demonstrated.

Cultured mammotropes incubated with dopamine for one hour exhibited changes in ultrastructure indicative of actively depressed biosynthetic and secretory activity. Peripheral relocation of rough endoplasmic reticulum appeared to create a barrier to secretory granule release by exocytosis. A decrease in the numbers of secretory granules indicated a decrease in prolactin production and enhanced lysosomal activity.

We recently succeeded in fabricating planar Hg1−yCdyTe/Hg1−xCdxTe (x

We report the results of annealing effects on the As-doped alloy HgCdTe grown by molecular beam epitaxy (MBE), arsenic (As) diffusion in HgCdTe from Hg-rich solutions at low temperatures, and As ion implantation at room temperature. Hall-effect measurements, secondary ion mass spectrometry and p-on-n test photodiodes were used to characterize the As activation. High As-doping levels (1017−1019 cm−3) could be obtained using either MBE growth, As diffusion or As ion-implantation. Annealed below 400°C, As doping in HgCdTe shows n-type characteristics, but above 410°C demonstrates that all methods of As doping exhibit p-type characteristics independent of As incorporation techniques. For example, for samples annealed at 436°C (PHg≈2 atm), in addition to p-type activation, we observe a significant improvement of p/n junction characteristics independent of the As source; i.e. As doping either in situ, by diffusion, or ion implantation. A study of this As activation of As-doped MBE HgCdTe as a function of anneal temperature reveals a striking similarity to results observed for As diffusion into HgCdTe and implanted As activation as a function of temperature. The observed dependence of As activation on partial pressure of Hg at various temperatures in the range of 250 to 450°C suggests that As acts as an acceptor at high Hg pressure (>1 atm) and as a donor at low Hg pressure (

Several dynamic analysis techniques are compared with a planar vehicle model. Cartesian formulation, suspension superelement technique, velocity transformation, and recursive formula are compared. The relation between the recursive formula and velocity transformation is investigated. When those techniques are applied to a planar vehicle with two independent suspensions, the efficiency of those methods was compared. The computational efficiency of the recursive formula was higher than those of other methods for the specific planar vehicle example.

Rapid thermal annealing (RTA) was applied to anneal polycrystalline CdTe thin films evaporated on CdS/ITO substrate and the effects of rapid thermal annealing temperatures and gas environments were studied. X-ray diffractometer (XRD), X-ray photoelectron spectroscopy(XPS), energy dispersive X-ray spectroscopy(EDX), cross-sectional transmission microscopy(TEM), and micro-EDX in TEM were used to characterize physical and chemical properties of rapid thermal annealed CdTe thin films. Complete CdTe/CdS photovoltaic cells were fabricated and I-V characteristics of these cells were measured under the illumination. Results showed that the bulk composition of CdTe remained stoichiometric to 550°C in the air environment and surface composition became Cd-rich. Cross-sectional TEM and micro-EDX showed columnar grains and micro-twins remained even after RTA, however, sulfur content in rapid thermal annealed CdTe caused by sulfur diffusion from CdS during the annealing was much smaller than that by furnace annealing. Among the investigated RTA temperatures and gas environments, the cell made with CdTe annealed at 550°C in the air showed the best solar energy conversion efficiency.

Thin epitaxial HgCdTe/CdTe photodiodes are shown to have lower dark current noise than similar thick devices. This is explained by the limited-diffusion-volume model which requires a thin diode and a low surface recombination rate. Electron beam induced current is used for characterizing minority electrons distribution; the characteristic interface recombinations(L/D) has been found to be equal to 0.05 at 80 and 210 K.R 0 A measurements give values consistent with this model.

HgMnCdTe/CdTe photodiodes with responsivity cutoffs of up to 1.54 pm have been fabricated by liquid phase epitaxy (LPE). The mesa device structure consists of a boron-implanted mosaic fabricated on a p-type Hg1−x−yMnxCdyTe layer grown on a CdTe substrate. A reverse breakdown voltage (VB) of 50 V and a leakage current density of 1.5 × 10−4 A/cm2 at V = −10 V was measured at room temperature (295K). A 0.75 pF capacitance was also measured under a 5 V reverse bias at room temperature. This device performance based on the quaternary HgMnCdTe shows both theoretical and practical promise of superior performance for wavelengths in the range 1.3 to 1.8 μm for fiber optic applications.