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Background 5-aminosalicylic acid (5-ASA) is widely used as a first-line treatment for ulcerative colitis (UC), but intolerance sometimes occurs. 5-ASA-intolerance was considered a risk factor for colectomy in UC patients, but no reports have examined which treatment is suitable to avoid colectomy in 5-ASA-intolerant UC patients. This is the first report describing a treatment strategy for 5-ASA-intolerant UC. The aims of this study were to determine the optimal therapeutic strategy in 5-ASA-intolerant UC patients. Methods This retrospective cohort study involved patients who were newly diagnosed as having UC after January 2010 and who received oral 5-ASA agents. Patients were considered 5-ASA-intolerant when they fulfilled two or more of the following conditions: (1) paradoxical aggravation of colitis on introducing oral 5-ASA agents or allergic reactions to the agents; (2) obvious improvement of abdominal symptoms after discontinuation of 5-ASA agents; (3) positive drug-induced lymphocyte stimulation test (DLST) for at least two formulations of 5-ASA; (4) adverse events following re-challenge with 5-ASA agents; and (5) severe adverse events owing to 5-ASA agents. Results Of 950 UC patients with a history of 5-ASA administration, 213 (22.4%) were considered 5-ASA-intolerant. Five-year colectomy-free survival was significantly lower in 5-ASA-intolerant patients compared with 5-ASA-tolerant patients (73% vs. 84%, respectively). From the multivariate Cox proportional hazards model analysis in the 5-ASA-intolerant patient cohort, thiopurine use was shown to contribute to avoidance of colectomy in 5-ASA-intolerant patients (hazard ratio = 0.25; 95% confidence interval, 0.13–0.47; P < 0.001); however, 5-ASA-intolerant patients were also likely to be thiopurine-intolerant compared with 5-ASA-tolerant patients (27% vs. 15%, respectively; P = 0.04). Calcineurin inhibitor use was associated with an increased risk of colectomy (hazard ratio = 4.80; 95% confidence interval, 2.24–10.3; P < 0.001), while treatment with systemic corticosteroids and biologics did not affect the colectomy rate (hazard ratio = 1.07; 95% confidence interval, 0.60–1.91; P = 0.81). Conclusion Treatment with thiopurines demonstrated the potential to improve the prognosis in 5-ASA-intolerant patients. However, it should be noted that thiopurine intolerance was more frequent in 5-ASA-intolerant patients. Compared to biologics, calcineurin inhibitors may not contribute to avoidance of colectomy, and biologics may be preferred for intractable patients with 5-ASA intolerance. This is the first report describing a treatment strategy for 5-ASA-intolerant UC, and we believe it will have many implications in clinical practice.

Disopyramide reduces the left ventricular outflow tract (LVOT) pressure gradient and improves symptoms in humans with hypertrophic obstructive cardiomyopathy (HOCM). However, the efficacy of disopyramide in cats has not been reported. We treated a cat with HOCM with carvedilol and disopyramide cotherapy and monitored the changes in LVOT flow velocity and N-terminal pro B-type natriuretic peptide (NT-proBNP) concentration. A 10-month-old neutered male Norwegian Forest cat was referred with a moderate systolic cardiac murmur. Echocardiography revealed thickening of the left ventricular wall, systolic anterior motion of the mitral valve leaflets, and turbulent aortic flow in the LVOT at systole. The LVOT flow velocity was 5.6 m/s. The plasma NT-proBNP concentration exceeded 1,500 pmol/L. The cat was diagnosed with HOCM and the β-blocker carvedilol was started and gradually increased to 0.30 mg/kg, bid. After 57 days, the LVOT flow velocity (4.8 m/s) and plasma NT-proBNP concentration (870 pmol/L) had decreased but remained elevated. Therefore, disopyramide was added at 5.4 mg/kg po bid and increased to 10.9 mg/kg po bid after 22 days. After 141 days of carvedilol and disopyramide treatment, the systolic anterior motion of the mitral valve leaflets had disappeared and the LVOT flow velocity and plasma NT-proBNP concentration had decreased to 0.7 m/s and 499 pmol/L, respectively. No adverse effect has been observed during the follow-up. Disopyramide might relieve feline LVOT obstruction after only partial response to a beta-blocker. Further large-scale studies are required to investigate the efficacy and safety of disopyramide use in cats with moderate to severe HOCM.

application/pdf, Previously, we have identified a gene encoding thrombospondin-related anonymous protein of Babesia gibsoni (BgTRAP), and have shown that the antisera raised against recombinant BgTRAP expressed in Escherichia coli inhibited the growth of parasites. In the present study, a recombinant vaccinia virus expressing the BgTRAP (VV/BgTRAP) was constructed. A specific band corresponding to a molecular mass of 80 kDa, which was similar to that of native BgTRAP on the merozoites of B. gibsoni, was detected in the supernatant of VV/BgTRAP-infected RK13 cells. Moreover, mice inoculated with VV/BgTRAP produced antibody that specifically reacted with the native BgTRAP on parasites. These results indicated that the recombinant vaccinia virus expressing BgTRAP might be a vaccine candidate against canine B. gibsoni infection.

Background Hypoxic cancer cells are thought to be radioresistant and could impact local recurrence after radiotherapy (RT). One of the major hypoxic imaging modalities is [18F]fluoromisonidazole positron emission tomography (FMISO-PET). High FMISO uptake before RT could indicate radioresistant sites and might be associated with future local recurrence. The predictive value of FMISO-PET for intra-tumoral recurrence regions was evaluated using high-resolution semiconductor detectors in patients with nasopharyngeal carcinoma after intensity-modulated radiotherapy (IMRT). Methods Nine patients with local recurrence and 12 patients without local recurrence for more than 3 years were included in this study. These patients received homogeneous and standard doses of radiation to the primary tumor irrespective of FMISO uptake. The FMISO-PET image before RT was examined via a voxel-based analysis, which focused on the relationship between the degree of FMISO uptake and recurrence region. Results In the pretreatment FMISO-PET images, the tumor-to-muscle ratio (TMR) of FMISO in the voxels of the tumor recurrence region was significantly higher than that of the non-recurrence region (p

We study Bell-state correlations for quasiparticle pairs excited in nonlinear current through a double quantum dot in the Kondo regime. Exploiting the renormalized perturbation expansion in the residual interactions of the local Fermi liquid and Bell's inequality for cross correlation of spin currents through distinct conduction channels, we derive an asymptotically exact form of Bell's correlation for the double dot at low bias voltages. We find that pairs of quasiparticles and holes excited by the residual exchange interaction violate Bell's inequality for the spin currents.

Background Takayasu’s arteritis (TA) is a rare complication associated with inflammatory bowel disease (IBD). TA is a granulomatous systemic vasculitis of uncertain aetiology affecting large arteries, predominantly the aorta and its main branches, leading to stenotic and expansible lesions. The estimated prevalence of coexisting of TA in patients with ulcerative colitis (UC) is 0.3%, and that in patients with Crohn’s disease (CD) is 0.1%. Anti-tumour necrosis factor-α (TNF-α) agents are used to treat both TA and IBD, although some patients with IBD paradoxically develop TA during treatment with anti-TNF-α agents. However, data regarding the incidence and clinical features of TA in such cases are lacking. This study was performed to clarify the prevalence, risk factors, and clinical features of TA that develops paradoxically during treatment with anti-TNF-α agents in patients with IBD. Methods Consecutive patients with IBD who were regularly seen at our centre, a tertiary IBD centre in Japan, from 2000 to 2019 were included in this retrospective single-centre study. We evaluated the prevalence of TA according to the presence or absence of treatment with anti-TNF-α agents and the patients’ clinical manifestations. Results Of 1846 patients with UC and 1249 patients with CD, 7 (0.23%) patients with UC developed TA. The prevalence of TA in patients treated with anti-TNF-α agents was significantly higher (4/254, 1.6%) than that in patients without anti-TNF-α agent treatment (3/1592, 0.19%) (p=0.0087, Fisher’s exact test). Among four patients with UC who paradoxically developed TA during treatment with anti-TNF-α agents, three (75%) received infliximab, one (25%) received adalimumab, and one (25%) received golimumab. One was male and three (75%) were female. The median interval from starting treatment with anti-TNF-α agents to diagnosis of TA was 49.0 (34–63) months. All patients had pancolitis as well as persistent active colitis resistant to anti-TNF-α antibody treatment. The treatments for TA administered after anti-TNF-α therapy were as follows: Two (50%) patients discontinued anti-TNF-α agent therapy, three (75%) were treated with prednisolone, and one (25%) received tocilizumab. No patient required an operation for TA. Conclusion To our knowledge, this is the first study to show the prevalence and clinical features of TA in patients with IBD following administration of anti-TNF-α agent therapy. Although TA is a rare complication, our results suggest that it can develop as paradoxical reaction following administration of anti-TNF-α agents.

Shigatoxigenic Escherichia coli (STEC) are major food-borne pathogens. They transmit to human through contaminated meat and meat products of animals and poultry, and frequently associated with various types of human illness including haemolytic uremic syndrome. This preliminary study showed the prevalence of STEC in 60 cloacal swab samples of live healthy broiler chickens collected randomly when sold at a wholesale market in Mymensingh district of Bangladesh. Isolation and identification of E. coli was carried out using Eosin Methylene Blue (EMB) agar media and 16S rRNA gene specific polymerase chain reaction (PCR). Among the 60 samples, 49 (81.67%) were found positive to E. coli . These E. coli isolates were screened for the detection of STEC by PCR using stx 1 and stx 2 gene specific primers. Among the 49 positive samples, 5 (10.20%) were found positive for stx 1 gene, and 26 (53.06%) were positive for stx2 gene. In addition, 6 (12.24%) isolates were found positive to both stx 1 and stx 2 genes, and the remaining 12 (22.46%) were negative. The high prevalence ofSTEC in the broiler chicken alarms the public health impact as the people are always in close contact with these live broiler chickens in the open market as well as processing of meat at home before cooking. However, further studies are required to uncover the major source(s) for the transmission of STEC to human in ruralBangladesh.

Background To decision to undergo surgical intestinal resection is among the most difficult that patients with inflammatory bowel disease (IBD) may be required to make during the disease course. Although the clinical outcomes and QoL after intestinal resection are well established, few studies have focused on psychological acceptance of the surgery, that is, how patients feel about the results of intestinal resection. The aim of this study was therefore to evaluate psychological acceptance of the surgical outcome in patients undergoing intestinal resection. Methods We administered a cross-sectional questionnaire survey to patients at five IBD centres in Japan who had undergone intestinal resection at least 1 month before the survey. Patients were asked to complete a visual analogue scale (VAS) questionnaire, consisting of 20 questions related to surgical acceptance and concerns related to IBD (body image, burden of treatment, interpersonal relationships), before and after surgery. The VAS scores before surgery were described by the patient looking back on recollection. Pre- and post-surgical VAS scores were compared using a Wilcoxon’s rank-sum test. Results A total of 64 patients participated in this study (median age at surgery 37.9 (range 12–67) years, median years after surgery 5.0 (range 0.1–21) years). The VAS scores before and after surgery were summarised in the figure. The score for ‘pleased to have surgical resection of my intestine’ improved significantly after the surgery in both UC and CD (p < .0001).Furthermore, the score for ‘burdened with treatment for my IBD’ improved significantly after surgery in UC patients (p < .0001). Conclusion Our findings indicate that surgical intestinal resection outcomes were psychologically well accepted by most IBD patients.

We study spin-entanglement of the quasiparticles of the local Fermi liquid excited in nonlinear current through a quantum dot described by the Anderson impurity model with two degenerate orbitals coupled to each other via an exchange interaction. Applying the renormalized perturbation theory, we obtain the precise form of the cumulant generating function and cross-correlations for the currents with spin angled to arbitrary directions, up to third order in the applied bias voltage. It is found that the exchange interaction gives rise to spin-angle dependency in the cross-correlation between the currents through the two different orbitals, and also brings an intrinsic cross-correlation of currents with three different angular momenta.

The Luttinger Theorem, which relates the electron density to the volume of the Fermi surface in an itinerant electron system, is taken to be one of the essential features of a Fermi liquid. The microscopic derivation of this result depends on the vanishing of a certain integral, the Luttinger integral $I_{\rm L}$, which is also the basis of the Friedel sum rule for impurity models, relating the impurity occupation number to the scattering phase shift of the conduction electrons. It is known that non-zero values of $I_{\rm L}$ with $I_{\rm L}=\pm\pi/2$, occur in impurity models in phases with non-analytic low energy scattering, classified as singular Fermi liquids. Here we show the same values, $I_{\rm L}=\pm\pi/2$, occur in an impurity model in phases with regular low energy Fermi liquid behavior. Consequently the Luttinger integral can be taken to characterize these phases, and the quantum critical points separating them interpreted as topological., Comment: 5 pages 7 figures

Background Five-aminosalicylic acid (5-ASA) compounds are used as the primary treatment for ulcerative colitis (UC); however, some patients are intolerant to this drug. There have been few studies on the natural history and clinical outcomes of 5-ASA intolerant patients. The aim of this study was to elucidate the clinical outcomes of 5-ASA intolerant patients in terms of colectomy, immunomodulator use, and biologic (anti-tumour necrosis factor (TNF) and Vedolizumab) therapy. Methods Data were obtained by a retrospective review of the charts of 2065 consecutive patients with UC who were treated with 5-ASA compounds at our tertiary referral inflammatory bowel disease (IBD) centre and a related IBD clinic from 2010 to 2020. Patients were considered to be intolerant to 5-ASA if they discontinued the drug because of any type of adverse effect. The cumulative rates of immunomodulator-, biologic- and colectomy-free survival rates in 5-ASA tolerant and intolerant patients were calculated using the Kaplan–Meier method. Additionally, Cox regression was used to analyse other factors besides 5-ASA intolerance contributing to clinical outcomes. Results Intolerance to 5-ASA was identified in 268 patients. The cumulative probability of colectomy within 10 years in 5-ASA intolerant patients was 23%, which is significantly higher than that in tolerant patients, 10% (log-rank test < 0.0001). Within 10 year, 63% of 5-ASA intolerant and 20% of tolerant patients received immunomodulators (log-rank test < 0.0001); and 37% of 5-ASA intolerant and 11% of tolerant patients received biologic therapy (log-rank test < 0.0001). Cox regression multivariate analysis identified that younger age, disease extent and 5-ASA intolerance were predictors of colectomy. Conclusion In this retrospective cohort study, 5-ASA intolerant patients had worse clinical outcomes than those who tolerated 5-ASA treatment. This is the first report on the long-term prognosis of 5-ASA intolerant patients.

We show that when there is a sudden transition from a small to a large Fermi surface at a field-induced quantum critical point, similar to what may have been observed in some heavy-fermion compounds, an additional term has to be taken into account in the Luttinger-Friedel sum rule.We calculate this additional term for a local model which has a field-induced quantum critical point (QCP) and show that it changes abruptly at the transition, such that it satisfies a generalized Luttinger-Friedel sum rule on each side of the transition, and characterizes the two Fermi-liquid phases separated by the QCP as a discrete (topological) index., Comment: 5 pages, 6 figures

We analyze conditions for the observation of a low energy SU(4) fixed point in capacitively coupled quantum dots. One problem, due to dots with different couplings to their baths, has been considered by Tosi, Roura-Bas and Aligia (2015). They showed how symmetry can be effectively restored via the adjustment of individual gates voltages, but they make the assumption of infinite on-dot and inter-dot interaction strengths. A related problem is the difference in the magnitudes between the on-dot and interdot strengths for capacitively coupled quantum dots. Here we examine both factors, based on a two site Anderson model, using the numerical renormalization group to calculate the local spectral densities on the dots and the renormalized parameters that specify the low energy fixed point. Our results support the conclusions of Tosi et al. that low energy SU(4) symmetry can be restored, but asymptotically achieved only if the inter-dot interaction $U_{12}$ is greater than or of the order of the band width of the coupled conduction bath $D$, which might be difficult to achieve experimentally. By comparing the SU(4) Kondo results for a total dot occupation $n_{\rm tot}=1$ and $n_{\rm tot}=2$ we conclude that the temperature dependence of the conductance is largely determined by the constraints of the Friedel sum rule rather than the SU(4) symmetry and suggest that an initial increase of the conductance with temperature is a distinguishing characteristic feature of an $n_{\rm tot}=1$ universal SU(4) fixed point., 14 pages and 20 figures

Summary Background. Recessive dystrophic epidermolysis bullosa (RDEB) is an autosomal recessive skin disease caused by mutations in the type VII collagen gene (COL7A1), resulting in detachment of the entire epidermis due to loss or hypoplasticity of the anchoring fibrils that normally secure the basement membrane to the underlying dermis. Trauma-induced blistering is often complicated by chronic erosions and scarring. From that perspective, pregnancy in RDEB might be considered an indication for elective caesarean section in a bid to minimize perineal blistering. To date, only four cases of pregnancy and delivery in patients with RDEB have been reported. Cases. We report three more women, each with RDEB-generalized other (RDEB-GO), all of whom had successful vaginal deliveries without major cutaneous or mucosal complications. One woman also had a second child, by vaginal delivery, indicating a lack of vaginal stenosis after the first birth. Conclusions. These cases show that RDEB-GO is not an absolute primary indication for elective caesarean section and that, perhaps surprisingly, genital/perineal blistering and scarring are not inevitable consequences of childbirth. Moreover, breastfeeding is also feasible in women with RDEB-GO.

Recycle-typed Fe3Al composites reinforced by Fe3AlC0.5 or TiC phases with several volume fractions were prepared from high-carbon Cr steel sludge, Al can scraps and pure-Ti metal. The feasibility of recycle-typed Fe3Al composites for practical use as cutting tools was investigated by conducting cutting tests under dry conditions using, as work materials, an Al alloy (A5056) for rough machining and pure-Cu (C1020) for finish machining. In the cutting tests of A5056 by rough machining, adhesive wear was the dominant wear mechanism. The ranking of tool life was inconsistent with that of tool hardness, and the tool life of recycle-typed Fe3Al (3.3Ti) was longer than that of high-speed steel (HSS). In the cutting tests of C1020 by finish machining, the tool lives of recycle-typed Fe3Al composites were longer than that of HSS. After a 9 min cutting test with a recycle-typed Fe3Al (1.9Ti) tool, the surface roughness of C1020 was 0.8 μm, about half of that cut with the HSS tool. These results suggested that recycle-typed Fe3Al composites have potential as cutting tools, and showed promise as viable alternatives to HSS.

金沢大学理工研究域環境デザイン学系, The estimation of risk due to rockfall is often done empirically. As a rational and effective method towards performance-based design of protection measures, a three-dimensional simulation method helps to describe the motion of rockfall on a slope and to consider the effect of vegetation probabilistically. This document details a typical simulation method and analyses the manner of rockfalls paired with interference of vegetation and other factors. As application, an actual slope is analyzed where rockfall occurred during the Noto Peninsula Earthquake. Finally, the validity and the benefits of the shown method are the basis for a hazard mapping for rockfall and the planning of measures.

In this study, an electromagnetic field approach is used to clarify the mechanism of on-body transmission. A homogeneous cylinder is used as an arm model, and the characteristic of electromagnetic field distribution around the cylinder is extracted based on surface wave approximation and numerical analysis, respectively. As a result, the surface wave approximation is found to be valid in the far-field region from the excitation source in the frequency range of 10-150 MHz. Moreover, in the near-field region of the excitation source, the attenuation along the cylinder surface is much smaller than that toward the outside. In addition, by using a numerical human body model, the path loss for on-body transmission is also formulated.

Tritium detrapping behavior in neutron-irradiated ternary lithium oxides was investigated by the comparison of the annihilation of irradiation defects with the tritium release. It was revealed that the annihilation of irradiation defects would consist of two processes; namely the fast and the slow ones. The slow annihilation process has correlation with the tritium release, indicating that E′-center or F+-center could act as tritium trapping site, and from its activation energy of each sample, the annihilation of E′-center and F+-center could be attributed to the recovery of oxygen via diffusion, triggering the tritium release. Meyer–Neldel plots of these results indicate that the slow annihilation process was governed by the formation entropy of a pair of vacancy and interstitial atom of oxygen. Therefore, the trapped tritium would be detrapped by oxygen recovery to E′-center or F+-center, and its kinetics would be determined by the population of oxygen vacancy under thermal equilibrium.

Deuterium ion implantation and subsequent X-ray Photoelectron Spectroscopy (XPS) and Thermal Desorption Spectroscopy (TDS) experiments were performed with varying implantation temperatures to reveal chemical behavior of tritium produced in Li 2 TiO 3 . These experimental results showed that there were four deuterium trapping states; two of which were interacted with and without oxygen near the surface, and the other two were interacted with E'-center and with oxygen with the formation of O-D bond in the bulk. These trapping states of deuterium in the bulk were almost the same as those of tritium generated in thermal neutron-irradiated Li 2 TiO 3 . The total amount of deuterium retention in the bulk was almost constant until O-D bonds formed in the bulk were decomposed, indicating that tritium trapping could proceed under hot atom chemical reactions. It was concluded that E'-center could trap the implanted deuterium more frequently than oxygen with the formation of O-D bonds in the bulk. Annihilations of them due to oxygen recovery could increase the retention of D with the formation of O-D bonds, resulting in the almost constant deuterium retention ratio up to its decomposition temperature of 573 K.

He + implantation effects on the Retention behavior of hydrogen isotopes implanted into 35% oxygen-contained boron film was studied by means of SEM, AFM, XPS and TDS. It was found that the D retention for only D 2 + implanted film was the highest and it decreased for pre-He + implanted film and post-He + implanted film. From the SEM and AFM images, the surface morphology of the oxygen-contained boron film was partly cracked, indicating that B 2 O 3 was formed in the film. From the TDS and XPS results, the defective structure and the formation of B-D-B bond, B-D bond and B-O-D bond were observed by He + and D 2 + implantation, respectively. It was suggested that oxygen was trapped as B-O bond. The reaction with implanted D 2 + was preceded in different mechanism.

We studied the wetting phenomena of liquid Se–Tl on a silica substrate, not only in the thermal equilibrium state but in non-equilibrium states created by a temperature gradient and a temperature jump. In the thermal equilibrium state, no apparent critical point wetting was observed, but a lowering of temperature apart from the critical temperature induced a wetting transition, and the surface was covered with a Se-rich film. This result cannot be explained by the Cahn’s critical point wetting theory. When the surface of the cell is heated up compared to the bulk, a transition from the wetting to non-wetting state is observed. In addition, we observed that a temporal wetting state is induced by a sudden decrease of temperature.

The implantation temperature dependence of hydrogen isotope behaviors in non-helium ion (He+) pre-implanted silicon carbide (SiC) and He+ pre-implanted SiC was studied by means of X-ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). It was found that the deuterium (D) retention decreases as the implantation temperature increases in both non-He+ pre-implanted SiC and He+ pre-implanted SiC after D2+ implantation. Above 800 K, D bound only to C in forming C–D bonds. The chemical states of Si 2p for non-He+ pre-implanted SiC and He+ pre-implanted SiC at implantation temperatures above 800 K are quite different from those at room temperature and a positive peak shift of Si 2p was observed, indicating Si–C–D bonds were formed without larger amount of retention of damaged structures. These facts indicate that damaged structures introduced by D2+ and/or He+ implantation are quickly recovered by the thermal annealing effect at temperature above 800 K. These results imply that the thermal annealing effect influence widely on the tritium behavior and damaged structures in SiC.

Deuterium retention behavior in highly oriented pyrolytic graphite (HOPG), poly-crystalline diamond, poly-crystalline SiC, sintered WC, and converted B4C were investigated to reveal tritium behavior in re-deposition and co-deposition layers. Such layers would contain carbon, when the first wall and/or divertor were made of graphite or carbon-containing materials. Furthermore, the employment of other materials such as tungsten, and first wall conditioning such as boronization would complicate the layers. No different deuterium trapping sites due to carbon from those in HOPG were found in all the samples, where two deuterium trapping processes were observed: hot atom chemical trapping of energetic deuterium by a dangling bond of carbon and thermochemical trapping of thermalized deuterium in a constituent atom vacancy surrounded by carbons. Additionally, the latter reaction could be easily counteracted by or competed with the other deuterium trapping reactions by constituent atoms.

Annihilation of irradiation defects and tritium release processes in the neutron-irradiated Li2SiO3 and Li4SiO4 were investigated by means of electron spin resonance and thermal desorption spectroscopy, respectively. The experimental results indicated that tritium release from both samples began just before the irradiation defects were completely annihilated. The isothermal annealing experiments for both samples showed that there were fast and slow annihilation processes of the defects with activation energies of 0.12 and 0.63 eV for Li2SiO3, and 0.12 and 0.56 eV for Li4SiO4. The fast annihilation process could result mainly from diffusion of trapped electrons into the defects, whereas the slow annihilation process could be attributed to the annihilation of E′-center by recovering oxygen ions (O−). Therefore, the annihilation of E′-center would trigger the tritium release. A model of annihilation of E′-center and tritium behavior in neutron-irradiated ceramic tritium breeding materials is also proposed.

Apoptosis has been found to help in the defence against pathogens. Infection with the obligate intracellular parasite Toxoplasma gondii is known to trigger host-cell apoptosis. When using a T. gondii-infected macrophage cell line, J774A.1, treatment with IFN-gamma significantly enhanced apoptosis in noninfected bystander cells while parasitized cells became relatively resistant. Infection and IFN-gamma treatment activated the expression of inducible nitric oxide synthase (iNOS), and the production of nitric oxide (NO) and treatment of cells with an iNOS inhibitor, N(G)-monomethlyl-L-arginine acetate (L-NMMA) reduced the apoptosis frequency. However, the reversal was only partial suggesting that not only NO, but also other, as of yet, unknown factors are induced. Finally, we studied the effect in vivo by infecting mice with either a virulent or an avirulent strain. Challenge with the virulent strain lead to a higher parasite burden, induced host-cell apoptosis in peritoneal cells, and produced higher levels of IFN-gamma and NO. Moreover, treatment of mice with a NO synthase inhibitor, aminoguanidine, partially inhibited the host-cell apoptosis induced by the parasite infection. Altogether, our findings indicate that apoptosis in bystander host cells is due to the secretion of NO and other soluble factors released by parasite-infected cells.

Dependence of implantation temperature on chemical behavior of energetic deuterium implanted into WC was investigated by TDS and XPS. 1.0 keV D + 2 ions were implanted into WC samples at the implantation temperature range of 323-873 K. It was found that the deuterium retention decreased as the implantation temperature increased. Above 573 K, most of the retained deuterium was bound to C, which was less than 20% of the total D retention after D + 2 implantation at 323 K. Above 673 K, C was segregated on the WC surface and some of the implanted deuterium was retained in the segregated carbon layer. Additionally, it can be said that the D retention in WC was much less than that in other carbon-related materials, such as graphite and SiC. Hydrogen isotope retention can be reduced significantly when WC is formed on a divertor surface as a redeposited layer.

The D2 + was irradiated into SiC up to the saturation and thereafter He+ irradiation was performed to elucidate interaction mechanism between hydrogen isotope retained in SiC and irradiated energetic He+ by means of X-ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). It was found that D was trapped by both of Si and C by D2 + irradiation and only D bound to Si interacted with irradiated He+ in the initial He+ irradiation stage. Some damaged structures were introduced into SiC by both of D2 + and He+ irradiation. By heating after the irradiation experiments, most of SiC structure was recovered at the temperature above 1000 K. However, some free C was migrated toward the surface and aggregated on the surface of SiC. This fact indicates that the C impurity would contaminate the plasma and/or the tritium breeding materials, which is thought to be contacted with the SiC inserts.

To elucidate the interaction between hydrogen isotopes and damaged structures in SiC, deuterium ion ( D 2 + ) was implanted into helium ion (He+) implanted SiC. The chemical state of SiC was analyzed by XPS and thermal desorption behaviors of D2 and He were observed by TDS. It was found that D desorption consisted of two stages, namely D bound to Si and that to C. The D was desorbed from both desorption stages for He+ implanted SiC with the low D 2 + fluence, although it was preferentially trapped by C for pure SiC. The D retention for He+ implanted SiC was lower than that for pure SiC under the same D 2 + fluence. The implanted He mainly forms He blister or remains in the carbon vacancies. The D trapping efficiency was changed by He+ implantation, although the D trapping mechanism was not largely influenced.

Thermal stability of para (p--) and ortho (o-) isomers was investigated by CRTG and reaction kinetic analysis. The temperature started the mass decrease of o-isomer was about 20°C lower than that of p-isomer by CRTG. The activation energies of thermal decomposition of o- and p-isomers were 136.9 and 153.4 kJ mol–1, respectively. The effect of steric hindrance on heat of formation was calculated by AM1 method using Win MOPAC3.0 for the model compound of p- and o-isomers. The lower stability of o-isomer was the results of the steric hindrance between the ethylene unit of aromatic ring and three alkyl chains.

Recently, we have investigated the annihilation behavior of the radiation defects and the tritium release behavior in/from some neutron-irradiated ceramic breeder materials. In the present study, correlation between the tritium release and the annihilation of irradiation defects were investigated for neutron-irradiated Li2ZrO3. The annihilation of irradiation defects consisted of two processes, the fast and the slow processes. The activation energies for these processes were determined to be 0.32 ± 0.01 and 0.80 ± 0.01 eV, respectively. The E′-center of irradiation defects was found to act as a tritium trapping site by comparison between the annihilation of irradiation defects and tritium release. From the present and the previous works, the annihilation process of oxygen vacancies such as E′-center and F+-center could play an important role in tritium behavior. The results of the present and previous studies suggest that there appears to be similar correlation between annihilation of irradiation defects and tritium release for several ceramic breeder materials.

TDS analyses have been performed in order to examine helium irradiation effects for deuterium retention in boron coating films prepared by PACVD. It is clarified that the deuterium retention is reduced due to the irradiation prior to deuterium. There is no correlation between the retention variations of deuterium and helium, and thus the helium occupation seems hardly to contribute to the reduction. The third peaks in the TDS spectra shift on the high temperature side with the irradiation fluence. It is presumed that helium irradiation forms certain layers by knocking on boron atoms, in which deuterium retention is partly restricted, and trapped deuterium needs higher energy for the desorption.

The chemical behavior of energetic deuterium implanted into tungsten carbide (WC) samples has been investigated by XPS and TDS. The TDS experiments showed that almost of all deuterium retained in WC was desorbed in the temperature region from 300 to 700 K and the residue at around 1000 K. The deuterium (D 2 ) desorption peak at around 1000 K was found to originate from the desorption of deuterium atom (D) trapped by carbon (C). Its retention was considerably small and was saturated at low deuterium ion (D 2 + ) fluence. The area of the large D 2 desorption peaks, which corresponds to the D retention in WC, increased as D 2 + fluence increased. The D 2 desorption in the temperature range of 300–700 K takes place in three stages, the lower two peaks were attributed to the desorption of D retained in two interstitial sites, and the highest peak corresponds to D trapped by carbon vacancies induced by chemical sputtering of C by energetic D 2 + . From these experimental results, the D trapping and detrapping behaviors are discussed and it is concluded that the hydrogen isotope retention is governed by the amount of interstitial sites and carbon vacancies in WC. The hydrogen isotope retention could be lowered if the surface temperature of WC were above 700 K.

The grain size distribution of B-doped cast-grown polycrystalline Si could not explain the minority carrier lifetime map. The lifetime was not mainly determined by the grain boundary recombination, since the grain size of the present cast-grown polycrystalline Si exceeded 1 cm and was large enough as compared with the minority carrier diffusion length (0.25 μm). In the region where lifetime was relatively short, there were many defects, which appeared as etch-pit by the Secco etching. The relationship between the etch-pit density and the minority carrier lifetime suggested that these defects acted as a recombination center and that they mainly determined the lifetime. There were many C atoms (>10 17 cm 3 ), which exist as substitutional impurities, in the as-grown wafer. The thermal annealing induced the C segregation, which might deteriorate the solar cell performance through the cell fabrication processes.