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A disease outbreak occurred in June 2012 among mud loach cultured on pond farms in Jangseong-gun, Jeollanam-do, Korea. Mortality rates reached up to 1.2% in the farm per day. Typical clinical signs were bleeding ulcer at the middle portion of head and haemorrhagic erosion of the operculum. Based on biochemical characteristics, the causative bacterium isolated from diseased fish was identified as Aeromonas sobria. The isolate expressed two haemolytic genes, aerolysin (sob) and haemolysin (asa1) genes. Histopathologically, liver showed hepatocellular vacuolar degeneration and congestion in sinusoids. The spleen exhibited necrotized splenocytes and haemorrhagic pulps. In the kidney, glomerular destruction, renal tubular necrosis and haemorrhage were observed. Experimental infection (infectious dose of 10(6), 10(7), and 10(8) cfu fish(-1)) of healthy mud loach with the isolate resulted in the development of clinical signs similar to those seen in the farm. By injection with an infectious dose of 10(6) cfu fish(-1), the mortality rate was 10.3% within 7 days post infection. A mortality rate of 60.9% was reached within 2 days when an infectious dose of 10(7) cfu fish(-1) was used. Otherwise, all fish died within 1 day when injected with 10(8) cfu fish(-1). The results demonstrated that A. sobria is involved in the morbidity and mortality of the farmed mud loach.

The structural, magnetic, and electronic structural properties of Ni0.2Cd0.3Fe(2.5-x)Al(x)O4 ferrite nanoparticles were studied via X-ray diffraction (XRD), transmission electron microscopy (TEM), DC magnetization, and near-edge X-ray absorption fine-structure spectroscopy (NEXAFS) measurements. Nanoparticles of Ni0.2Cd0.3Fe(2.5x)Al(x)O4 (0 < or = x < or = 0.4) ferrite were synthesized using the sol-gel method. The XRD and TEM measurements showed that all the samples had a single-phase nature with a cubic structure, and had nanocrystalline behavior. From the XRD and TEM analysis, it was found that the particle size increases with Al doping. The DC magnetization measurements revealed that the blocking temperature increases with increased Al doping. It was observed that the magnetic moment decreases with Al doping, which may be due to the dilution of the sublattice by the doping of the Al ions. The NEXAFS measurements performed at room temperature indicated that Fe exists in a mixed-valence state.

The effects of Ce addition on the microstructure, age hardening response and mechanical properties of an indirect-extruded Mg-5wt.%Sn-4Zn (TZ54) alloy were investigated. Addition of Ce accelerated the aging response with the peak aging time moving from 300 h in TZ54 to 30 h in Mg-5wt.%Sn-4Zn-1Ce (TZE541), while the peak harness was similar to each other. The addition of Ce also caused an increase in the precipitation stability during overageing. Though the tensile strength of extruded TZ54 was improved by the addition of Ce, the tensile strength of the TZE541 was reduced after T6-treatment. The combined mechanical properties of the present as-extruded alloys by solution heat-treatment and artificial aging (T6) were comparable to commercial wrought magnesium alloys.

A theoretical model for the potentiometric analysis of precipitation titrations using a pH electrode has been developed and tested. The new analytical method is possible by introducing a mediator which must be a weak acid and must be able to form an insoluble salt with a cation (a titrant). Theoretical expressions of pH, as well as the concentrations of all other species, were derived and solved numerically using bisection method. Among the various factors that influence pH during the titration, concentrations of the mediator and initial values of pH were proved to be very critical. The experimental potentiometric titration curves agree well with those predicted from the theoretical model. Crossing point method was adopted to determine an equivalence point from the titration curves. The method is tested using a known system of chloride determination. Among the several mediators tested (bisulfite, chromate, phosphate, cyanide, arsenate and EDTA), phosphate yielded the best results with an error of 0.1%; bisulfite, chromate and arsenate yielded comparably good results with an error of 0.3∼0.5%, but cyanide and EDTA yielded unsatisfactory results. The optimum mediator concentration found to be in a range of 1–2 mM.

Our previous studies, using cDNA microarray and real-time reverse transcription-polymerase chain reaction, showed that acetylcholinesterase T subunit (AChET) gene was more abundantly expressed in the hypothalamus of the responder rats that were sensitive to electroacupuncture (EA) in the tail flick latency (TFL) test than in that of the non-responder rats that were insensitive to EA. In this study, we hypothesized that the expression of the AChET gene in the hypothalamus modulates EA analgesia in rats. To explore the hypothesis, we constructed an AChET-encoding adenovirus and a control virus expressing only green fluorescence protein, either of which was then injected into the hypothalamus of Sprague-Dawley rats. The hypothalamic activity of acetylcholinesterase was significantly higher in rats that were injected with the AChET virus than in rats that were injected with the control virus. The basal pain threshold measured by a TFL test was not changed by microinjection of AChET or control virus into the hypothalamus when EA treatment was not conducted. However, the analgesic effect of EA was significantly enhanced from 7 days after microinjection of the AChET virus into the hypothalamus but not after injection of the control virus. Furthermore, expression of the AChET in the hypothalamus did not affect body core temperature, body weight, motor function or learning and memory ability. Taken together, these results suggest that adenoviral expression of the AChET gene in the hypothalamus potentiates EA analgesia in rats without apparent side-effects.

The thermal stability of the hysteretic properties and domain structures of exchange-coupled Co–Fe/Ir–Mn and Ni–Fe/Ir–Mn bilayers was studied. Using the magneto-optical indicator film technique, X-ray diffractometry and VSM, we have revealed that the layers’ crystal structures are more regular, and also play the main role in the bilayer remagnetization process after annealing procedures. It was found that post-annealing crystal structure leads to changes in the magnetization reversal process. This effect is greater in the Ni–Fe bilayer than in the Co–Fe bilayer.

Electrochemical method has been applied for preparing Co/Cu multilayered thin films. The layers were electrodeposited after injecting Co and Cu containing solutions in a flow exchanged supporting electrolyte solution. In X-ray diffraction at low angle range a long period peak could be observed, and in the middle angle region a single broad peak showing an average lattice spacing of the film was observed. The electrical resistance showed the properties of Giant Magnetoresistance (GMR). The GMR ratio showed a variation against Cu layer thickness as expected for anti-ferromagnetically coupled films. The maximum GMR ratio obtained in this study was 6.2% at room temperature for the film of [Co 2.0 nm/Cu 1.0 nm] 15 . Though we need further studies for choosing suitable deposition conditions, the electrodeposition method is a promising method for producing multilayered thin films.

We present room-temperature pseudodielectric function spectra 〈e〉 of InxGa1−xAs films grown on (100) InP by solid-source molecular-beam epitaxy. A wet-chemical etching procedure is used to remove overlayers and obtain the best approximation to the bulk dielectric responses e of the films. By line shape fitting, we determined the x dependences of the E1 and E1+Δ1 critical-point energies and that of the Δ1 bowing parameter. The results are in good agreement with the predictions of a universal tight-binding model.

This paper reports the effect of Fe doping on the structure and room temperature ferromagnetism of CeO2 nanoparticles. X-ray diffraction and selective area electron diffraction measurement reflects that Ce1-xFexO2 (x = 0.0 - 0.07) nanoparticles exhibit single phase nature with cubic structure and none of the sample showed the presence of any secondary phase. The mean particle size calculated by using a transmission electron microscopy measurement was found to increase with increase in Fe content. DC magnetization measurements performed at room temperature indicates that all the samples exhibit ferromagnetism. The saturation magnetic moment has been found to increase with an increase in the Fe content., 16 Pages, 5 figure, 1 Table, Accepted in JNN

The structural, magnetic, and electronic structural properties of Ni0.2Cd0.3Fe(2.5-x)Al(x)O4 ferrite nanoparticles were studied via X-ray diffraction (XRD), transmission electron microscopy (TEM), DC magnetization, and near-edge X-ray absorption fine-structure spectroscopy (NEXAFS) measurements. Nanoparticles of Ni0.2Cd0.3Fe(2.5x)Al(x)O4 (0or = xor = 0.4) ferrite were synthesized using the sol-gel method. The XRD and TEM measurements showed that all the samples had a single-phase nature with a cubic structure, and had nanocrystalline behavior. From the XRD and TEM analysis, it was found that the particle size increases with Al doping. The DC magnetization measurements revealed that the blocking temperature increases with increased Al doping. It was observed that the magnetic moment decreases with Al doping, which may be due to the dilution of the sublattice by the doping of the Al ions. The NEXAFS measurements performed at room temperature indicated that Fe exists in a mixed-valence state.

We present the results of the formation of the InAs quantum dots (QDs) on the (100) In1−xAlxAs(InAlAs)/InP substrate by using relaxed InAlAs buffer layers with different compositions. Variations of surface morphology of InAs QDs as a function of InAs–InAlAs lattice mismatch have been evaluated by atomic force microscopy. When the lattice mismatch increases from 2.4% to 4.2%, the size of QDs decreases, and the density of QDs increases. Each of these dependences can be fitted to a power function of the misfit unless the Al diffusion, roughness of the buffer layer, and/or the ripening of small dots modify the size and density.

N-type ZnTe layers with high electron concentration are grown by molecular-beam epitaxy using aluminum as the donor species. The ZnTe:Al layers show a high structural quality with a narrow x-ray diffraction linewidth (24 arcsec) and a high carrier concentration up to n=4×1018 cm−3 with low resistivity (ρ=0.017 Ω cm). The dependence of the electron mobility on the carrier concentration suggests that the dominant scattering mechanisms in the ZnTe:Al layers are ionized impurity scattering and polar optical phonon scattering. The photoluminescence spectrum of moderately doped ZnTe layers shows strong Al–donor-related bound exciton lines: I2 (2.378 eV) and donor–acceptor pair emission (zero phonon energy=2.324 eV) with a weak deep-level emission (2.19 eV). Highly Al-doped layers show an increase in the deep-level emission intensity and a decrease in carrier mobility, which are interpreted in terms of the increase in the carrier compensation.

We report room temperature ferromagnetism in Ni doped CeO2 nanoparticles using X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), and dc magnetization measurements. Nanoparticles of Ce(1-x)Ni(x)O2 (0.0or = xor = 0.10) were prepared by using a co-precipitation method. XRD measurements indicate that all samples exhibit single phase nature with cubic structure and ruled out the presence of any secondary phase. Lattice parameters, strain and particle size calculated from XRD data have been found to decrease with increase in Ni doping. Inter-planner distance measured from HR-TEM images for different Ni doped samples indicate that Ni ions are substituting Ce ions in CeO2 matrix. Magnetization measurements performed at room temperature display weak ferromagnetic behavior of Ce(1-x)Ni(x)O2 (0.0or = xor = 0.10) nanoparticles. Magnetic moment calculated from magnetic hysteresis loop was found to increases with Ni doping up to 7% and then start decreasing with further doping.

Effects of the strain distribution on the optical gain of InGaN-AlInGaN QW light-emitting diodes (LEDs)is investigated. The amount of stress and strain in the multilayer quantum well structures are calculated taking into account the difference between crystalline parameters. Siginificant enhancement of optical gain is expected with the introduction of strain distribution layers.

Advanced neoplastic diseases alter the immune response in cancer patients. The aim of this study was to evaluate the changes of T-lymphocyte subsets during postoperative adjuvant chemotherapy, and the relationship between T-lymphocyte subsets and tumor recurrence in AJCC stage III gastric cancers.Analysis of T-lymphocyte subsets was performed in 39 patients with stage III gastric adenocarcinoma who had undergone a curative gastric resection and postoperative chemotherapy. CirculatingT-lymphocyte subsets were measured on venous blood by using flow cytometry and monoclonal antibodies on preoperative day 1, and postoperative months 1, 3, and 6.The 5-year disease-free survival rates of patients with stage 3a and 3b gastric cancer were 57.1% and 33.3%, respectively (p = 0.06). Values of CD3+ and CD4+ T-cells, and CD4+/CD8+ ratios were consistently lower in the recurrence group throughout the observation period. CD4+ T-cell counts were significantly lower in the recurrence group on preoperative day 1, and postoperative months 1 and 6. However, most values of the T-lymphocyte subsets showed no statistically significant difference when comparing the stage 3a and 3b disease patient groups.The results of this study suggest that immunosuppression associated with CD3+ and CD4+ T-cell depression is a risk factor for postoperative recurrence in patients with stage III gastric cancer.

Polycrystalline Fe-doped Ce1−xFexO2−δ has been fabricated by using the standard solid state reaction technique in the concentration range 0 ≤ x ≤ 0.05. Reitveld refinement of the X-ray diffraction patterns shows a pure CeO2 phase when x ≤ 0.03, and the appearance of a secondary impurity phase of Fe2O3 beyond that. Furthermore, by doping Fe into CeO2 powder, the ferromagnetism can be significantly enhanced to a maximum value for x = 0.03, but degrades quickly with further doping. Magnetization results reveal that the large room-temperature ferromagnetism observed in Fe-doped CeO2 powder originates from a combined effect of oxygen vacancies and transition metal doping.

We report room temperature ferromagnetism (RTFM) in Co-doped ZnO (Zn1−xCoxO; x = 0.01 − 0.05) powder synthesized using a co-precipitation method. Our magnetometry data reveal a weak FM behavior at RT in the range 0.01 < x < 0.05. FM by magnetic FM moment steadily decreases with increasing dopant. The O K-edge near-edge X-ray absorption fine structure (NEXAFS) spectra indicate that O vacancies increases with increasing Co concentration and that the sample with x ≥ 0.03 has more broadening at 535 and 540 eV, which may be due to the oxygen vacancies. Co in the ZnO host reveals a +2 oxidation state via the K edge NEXAFS spectra.