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Magnesium (Mg) alloy sheets have low density and high specific strength; thus, they are expected to facilitate weight reduction of structural components. However, because of the strong crystal anisotropy of the hexagonal structure and the strong basal texture observed in typical rolled Mg alloy sheets, their press formability at room temperature is low. To improve the room-temperature press formability, ZX series Mg alloy sheets that weakened the basal texture have recently been developed. The plastic deformation behavior of a rolled Mg-1.5mass%Zn-0.1mass%Ca (ZX10Mg) alloy sheet was studied in a previous study [7], and it was reported that the plastic deformation behavior showed strong in-plane anisotropy and differed notably from that of AZ series rolled Mg alloy sheets. In the present study, cylindrical cup drawing of a ZX10Mg alloy sheet was performed at room temperature and the drawability was examined in terms of cup height distributions, strain evolution, and texture evolution. The cup height differed significantly between the rolling and transverse directions. The thickness at the cup edge was the largest in the rolling direction and the smallest in the transverse direction. The magnitude relationship of the thickness correlated with the Lankford values under compression. The mechanism that yielded the difference in texture evolution was also discussed.

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.

C. Vastel et al., [Aims] Methanol is a ubiquitous species commonly found in the molecular interstellar medium. It is also a crucial seed species for the build-up of chemical complexity in star forming regions. Thus, understanding how its abundance evolves during the star formation process and whether it enriches the emerging planetary system is of paramount importance., [Methods] We used new data from the ALMA Large Program FAUST (Fifty AU STudy of the chemistry in the disc/envelope system of solar protostars) to study the methanol line emission towards the [BHB2007] 11 protobinary system (sources A and B), where a complex structure of filaments connecting the two sources with a larger circumbinary disc has previously been detected., [Results] Twelve methanol lines have been detected with upper energies in the [45–537] K range along with one 13CH3OH transition and one methyl formate (CH3OCHO) line blended with one of the methanol transitions. The methanol emission is compact (FWHM ~ 0.5″) and encompasses both protostars, which are separated by only 0.2″ (28 au). In addition, the overall methanol line emission presents three velocity components, which are not spatially resolved by our observations. Nonetheless, a detailed analysis of the spatial origin of these three components suggests that they are associated with three different spatial regions, with two of them close to 11B and the third one associated with 11A. A radiative transfer analysis of the methanol lines gives a kinetic temperature of [100–140] K, an H2 volume density of 106–107 cm−3 and column density of a few 1018 cm−2 in all three components with a source size of ~0.15″. Thus, this hot and dense gas is highly enriched in methanol with an abundance as high as 10−5. Using previous continuum data, we show that dust opacity can potentially completely absorb the methanol line emission from the two binary objects., [Conclusions] Although we cannot firmly exclude other possibilities, we suggest that the detected hot methanol is resulting from the shocked gas from the incoming filaments streaming towards [BHB2007] 11A and B, respectively. Higher spatial resolution observations are necessary to confirm this hypothesis., This project has received funding within the European Union’s Horizon 2020 research and innovation program from the European Research Council (ERC) for the project The Dawn of Organic Chemistry (DOC), grant agreement no. 741002, and from the Marie Sklodowska-Curie for the project Astro-Chemical Origins (ACO), grant agreement no. 811312. I.J.-S. has received partial support from the Spanish State Research Agency (project number PID2019-105552RB-C41). D.J. is supported by NRC Canada and by an NSERC Discovery Grant. S.Y. thanks the support by Grant-in-Aids from Ministry of Education, Culture, Sports, Science, and Technologies of Japan (18H05222). This paper makes use of the following ALMA data: ADS/JAO.ALMA#2018.1.01205.L. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

Background Intestinal Behçet's disease (BD) is a relapsing-remitting disease typically associated with punched-out ulcers in the ileocecal region. Optimal monitoring of disease activity is necessary; however, ileocolonoscopy cannot be performed on a regular basis as it is invasive, resource-intensive and causes considerable patient discomfort. Furthermore, there are risks of intestinal bleeding and perforation caused by pretreatment laxatives and air insufflation during the examination. Hence, other follow-up examinations are required. Intestinal ultrasonography (IUS) is a minimally invasive imaging method, but there are no previous reports of comparisons between IUS and endoscopy for intestinal BD. This study aimed to evaluate the usefulness of IUS in assessing the activity of ileocecal ulcers in intestinal BD. Methods This retrospective single-centre study included patients with intestinal BD who underwent colonoscopy and IUS within 2 weeks, from 2007 to 2020. Correlations between the corresponding endoscopic activity using the Sakita–Miwa classification and six IUS variables (bowel wall thickness [BWT], vascularity, bowel wall stratification, intramural and extramural abscesses, fistulas and mesenteric lymphadenopathy) were assessed and used to select the variables that should be included in the new simple score. IUS findings were also compared with biomarker (C-reactive protein [CRP]) concentrations and clinical severity indices (Crohn’s disease activity index and disease activity index for intestinal BD [DAIBD]). Results Seventy-nine IUS examinations from 53 patients were included. Univariate analysis revealed that CRP and DAIBD and the IUS findings BWT, vascularity and bowel wall stratification and intramural and extramural abscesses differed significantly according to endoscopic ulcer activity. Multivariate analysis using a logistic regression model revealed that only BWT and vascularity were statistically different; therefore, a new simple score ([2*BWT] + [5*vascularity]) was constructed. Receiver operating characteristic curve analysis revealed an area under the curve of 0.91 for detecting endoscopic activity, which was superior to those of CRP (0.80; P=0.069), Crohn’s disease activity index (0.69; P=0.002) and DAIBD (0.67; P Conclusion A new simple ultrasound activity index for intestinal BD comprising BWT and vascularity was constructed and correlated well with endoscopic disease activity. This is the first report describing the usefulness of IUS for intestinal BD, and we believe the findings will have many implications in clinical practice.

Neuropathic pain is a chronic disability associated with a dysfunction of the nervous system, initiated by a primary lesion or disease. Even after resolution of the initiating pathology, neuropathic pain often persists, leading to a significantly diminished quality of life. A vast literature has documented alterations in the expression and distribution of various pain-related proteins in the peripheral nervous system following injury or disease. The current review examines pain-related molecules in the pathogenesis of peripheral nerve injury-induced pain and discusses potentially useful therapeutic targets on the basis of preclinical findings in rodent neuropathic pain models. There are indeed a number of cellular processes that are involved in maintaining the neuropathic pain state, but the current review will focus on transmembrane proteins, particularly the voltage-gated and ligand-gated ion channels, which modulate peripheral nerve function. Given the complexity of the process involved in peripheral nerves, clinical efficacy could be greatly enhanced if several of these targets are engaged at once. A key advantage of therapy directed peripherally is that penetration of the therapeutic into the CNS is not entirely necessary, thereby reducing the risk of adverse psychomotor effects. While a number of fascinating targets have been identified in preclinical rodent models, there is a need to confirm that they are in fact relevant to clinical neuropathic pain. Thus, the current review will also discuss the extent to which clinical data confirms the findings of preclinical studies.

Evaluation of potential analgesic therapeutics and the elaboration of the neurobiology of pain have heavily relied on pain models developed in rodents. However, a limitation of rodents is their phylogenetic distance from humans, which could in part account for the failure of some preclinical findings to translate to clinical utility. By contrast, given their genetic closeness and phenotypic similarities to humans, it is suggested that there be greater utilization of non-human primates (NHP) in preclinical pain studies. Methods to induce chronic pain-like states and quantify changes in nociception that have been developed in rodents could be adapted to the NHP. Similarly, human experimental injury-induced sensitization, which attempts to temporarily mimic the neuropathology and symptoms observed in the chronic pain state, could be adapted to the NHP. The NHP could then serve as a platform to validate human experimental models as well as proof-of-concept studies. Beyond experimentally modeled pain states, a number of naturally occurring disease states, such as osteoarthritis, are expressed by NHP, which could be utilized for both hypothesis testing and proof-of-concept studies. While NHP studies are logistically cumbersome, it is envisioned that NHP pain models will add value to current preclinical data and greatly facilitate the discovery of novel analgesic treatments.

Japanese paddy rice systems commonly adopt the rotation of vegetables, wheat and soybeans with paddy rice. Crop rotation may, however, increase the nutrient load in effluent discharged from the district because more fertilizer is applied to the rotation crops than is applied to paddy crops. We investigated a paddy-field district subject to collective crop rotation and quantified the annual nutrient load of effluent from the district in three consecutive years. The total annual exports of nitrogen and phosphorus over the investigation period ranged from 30.3 to 40.6 kg N ha–1 and 2.62 to 3.13 kg P ha–1. The results suggest that rotation cropping increases the effluent nutrient load because applied fertilizer is converted to nitrate, and surface runoff is increased due to the absence of shuttering boards at the field outlets.

Because of the increasing demand for automobile outer panels with sharper streamlines, prevention of surface roughening during press forming is important to obtain outer panels with better surfaces. It is crucial to examine the effects of deformation-mode on surface roughening, because steel sheets are subjected to various deformation modes during press forming. Moreover, surface roughening behaviour of interstitial free (IF) steels, which are now commonly utilized for fabricating outer panels, has not been studied enough. In this study, surface roughening behaviours of IF steel under various deformation modes were simulated by crystal plasticity finite-element analysis (CPFEA). First, the validation of a CPFEA model was carried out for investigating the stress-strain relationships in simple shear deformation and for studying changes in crystal orientations during biaxial tension. Then, the influence of microstructures on surface roughening was investigated. The results showed that surface roughening was larger for plane-strain tension than for equi-biaxial tension in IF steels. To predict surface roughening, it is essential to consider the difference of deformation resistance between crystals and the distribution of crystal orientations in the thickness direction., NUMISHEET 2018: 11th International Conference and Workshop on Numerical Simulation of 3D Sheet Metal Forming Processes. 30 July to 3 August 2018, Tokyo, Japan.

This study concerns twist phenomena occurring in curved hat channel products and aims to clarify the causes of twist using physical quantities obtained by finite element analysis. Several drawing heights were examined. We evaluated the torque around the longitudinal axis, which can be regarded as the driving force of the twist. In addition, transitions of the torque during the process of tool removal were analyzed. After removing the die and blank holder, the twist torque in models with larger drawing heights became negative, accounting for the positive twist, which occurs after punch and pad removal. On the other hand, the twist torque in models with smaller drawing heights remained positive, accounting for the negative twist. Such analyses of the transition of twist torque provide useful information when considering measures for reducing twist.

Si ion implantation was widely used to synthesize specimens of SiO 2 containing supersaturated Si and subsequent high temperature annealing induces the formation of embedded luminescent Si nanocrystals. In this work, the potentialities of excimer UV-light (172 nm, 7.2 eV) irradiation and rapid thermal annealing (RTA) to enhance the photoluminescence and to achieve low temperature formation of Si nanocrystals have been investigated. The Si ions were introduced at acceleration energy of 180 keV to fluence of 7.5 × 10 16 ions/cm 2 . The implanted samples were subsequently irradiated with an excimer-UV lamp. After the process, the samples were rapidly thermal annealed before furnace annealing (FA). Photoluminescence spectra were measured at various stages at the process. We found that the luminescence intensity is strongly enhanced with excimer-UV irradiation and RTA. Moreover, effective visible photoluminescence which is not observed with a simple FA treatment, is found to be observed even after FA at 900 °C, only for specimens treated with excimer-UV lamp and RTA. Based on our experimental results, we discuss the effects of excimer-UV lamp irradiation and RTA process on Si nanocrystals related photoluminescence.

Si ion implantation was widely used to synthesize specimens of SiO2 containing supersaturated Si and subsequent high temperature annealing induces the formation of embedded luminescent Si nanocrystals. In this work, the potentialities of excimer UV-light (172 nm, 7.2 eV) irradiation and rapid thermal annealing (RTA) to enhance the photoluminescence and achieve low temperature (below 1000 o C) formation of Si nanocrystals have been investigated. The Si ions were introduced at acceleration energy of 180 keV to fluence of 7.5 x 10 16 ions/cm 2 . The implanted samples were subsequently irradiated with a excimer-UV lamp. After the process, the samples were rapidly thermal annealed before furnace annealing (FA). Photoluminescence spectra were measured at various stages at the process. We found that the luminescence intensity is strongly enhanced with excimer-UV irradiation and RTA prior to conventional FA at 1050 o C. Moreover, effective visible photoluminescence is found to be observed even after FA at 900 o C, only for specimens treated with excimer-UV lamp and RTA, prior to a low temperature FA process. Based on our experimental results, we discuss the effects of excimer-UV lamp irradiation and RTA process on the luminescence.

Si ion implantation was widely used to synthesize specimens of SiO 2 containing supersaturated Si and subsequent high temperature annealing induces the formation of embedded luminescent Si nanocrystals. In this work, the potentialities of excimer UV-light (172 nm, 7.2 eV) irradiation and rapid thermal annealing (RTA) to achieve low temperature (below 1000 °C) formation of luminescent Si nanocrystals in SiO 2 have been investigated. The Si ions were introduced at acceleration energy of 180 keV to fluences of 7.5 × 10 16 and 1.5 × 10 17 ions/cm 2 . The implanted samples were subsequently irradiated with an excimer-UV lamp for 2 h. After the process, the samples were rapidly thermal annealed at 1050 °C for 5 min before furnace annealing (FA) at 900 °C. Photoluminescence spectra were measured at various stages at the process. Effective visible photoluminescence is found to be observed even after FA at 900 °C, only for specimens treated with excimer-UV lamp and RTA, prior to a low temperature FA process. Based on our experimental results, we discuss the mechanism for the initial formation process of the luminescent Si nanocrystals in SiO 2 , together with the effects with excimer lamp irradiation and RTA process on the luminescence.

Calcination of a gallium-N-phenylene-N hybrid copolymer under an argon atmosphere gave nano-sized gallium nitride–carbon cluster composite material. ESR spectral examinations of the calcined materials reveals the possibility of an electron transfer in the process of gallium nitride → carbon clusters with an oxidation site at gallium nitride particles and a reduction site at carbon clusters. The calcined material was found to reduce methylene blue under visible light irradiation.

It is well known that Si implantation into SiO 2 and subsequent high temperature annealing induce the formation of embedded luminescent Si nanocrystals. In this work, potentialities of rapid thermal annealing to enhance the photoluminescence have been investigated. Ion implantation was used to synthesize specimens of SiO 2 containing supersaturated Si with different concentrations. The implanted samples were subsequently annealed at 1050 °C for several hours using a conventional tube furnace. Some of the samples were rapidly thermal annealed at 1050 °C or 1100 °C for only 5 min with different rising ratio from 10 to 50 °C/s. Photoluminescence spectra were measured at various stages of annealing processes. The luminescence intensity is strongly enhanced with a rapid thermal annealing before conventional furnace annealing. Moreover, the luminescence peak energy is found to be dependent, but a little, on thermal history of specimens. The luminescence intensity is known to be determined by the number of Si nanocrystals. In forming the Si nanocrystals in a SiO 2 matrix by high temperature annealing, decomposition, diffusion, nucleation, growth and crystallization processes are clearly important. The experimental results indicate that the rapid thermal annealing is effective for the initial process in forming Si nanocrystals, especially for low dose specimens. Based on the results, we discuss about the mechanism of an enhancement of the photoluminescence from embedded Si nanocrystals with rapid thermal annealing.

We studied the growth technique for the dislocation reduction in a-plane GaN grown by metal organic chemical vapour deposition (MOCVD) using AlInN buffer layer, high temperature atomic layer epitaxy, and trenched r-sapphire technique. By using these techniques, the crystal quality was much improved. We also fabricated blue light emitting diodes (LEDs) on a-plane GaN film over r-sapphire substrate and on a-plane bulk GaN substrate. The electroluminescence (EL) characteristics of the LED samples were examined, and we found that the EL near field pattern from homo-epitaxially grown a-GaN based LED was spatially uniform, although the pattern from the LED on r-sapphire substrate was not uniform. The output power at the wavelength of 430nm was 0.72mW at the 20mA injection current for the sample on a-plane bulk GaN. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Si ion implantation into SiO 2 and subsequent high temperature anneals induce the formation of embedded luminescent Si nanocrystals. The potentialities of rapid thermal annealing to enhance the photoluminescence as well as those to induce low temperature formation of luminescent Si nanocrystals have been investigated. Si ion implantation was used to synthesize specimens of SiO 2 containing supersaturated Si with different concentrations, from 4 to 16% in excess. The implanted samples were rapidly annealed only for a few minutes. After that, in some cases before that, the samples were annealed for a few hours using a conventional quartz tube furnace to induce Si precipitation. Photoluminescence spectra were measured at various steps of anneal processes. The luminescence intensity is strongly enhanced with a rapid thermal annealing prior to a conventional furnace anneal. The luminescence intensity, however, decreases when rapid thermal annealing follows conventional furnace annealing. It is found that the order of heat treatment is an important factor in intensities of the luminescence. Enhancement is found to be typical for low dose samples. Moreover, the visible photoluminescence is found to be observed even after conventional furnace anneal below 1000 °C, only for rapidly thermal annealed samples. Based on our experimental results, we discuss the mechanism for the enhancement of the photoluminescence, together with the mechanism for the initial formation process of luminescent Si nanocrystals.

Si ion implantation was widely used to synthesize specimens of SiO2 containing supersaturated Si and subsequent high temperature annealing induces the formation of embedded luminescent Si nanocrystals. In this work, the potentialities of excimer UV-light (172 nm, 7.2 eV) irradiation and rapid thermal annealing (RTA) to enhance the photoluminescence and to achieve low temperature formation of Si nanocrystals have been investigated. The Si ions were introduced at acceleration energy of 180 keV to fluence of 7.5 x 1016 ions/cm2. The implanted samples were subsequently irradiated with an excimer-UV lamp. After the process, the samples were rapidly thermal annealed before furnace annealing (FA). Photoluminescence spectra were measured at various stages at the process. We found that the luminescence intensity is strongly enhanced with excimer-UV irradiation and RTA. Moreover, effective visible photoluminescence is found to be observed even after FA at 900 oC, only for specimens treated with excimer-UV lamp and RTA. We also prepared specimens of Si nanocrystals embedded in a SiO2 by reactive pulsed laser deposition (PLD) in an oxygen atmosphere. We will make clear the similarities and differences with the way of preparation., {"references":["L. T. Canham, Silicon quantum wire array fabrication by electrochemical\nand chemical dissolution of wafers,\" Appl. Phys. Lett., 57, 1046 (1990).","V. Lehmann, U. Gösele, \"Porous silicon formation: A quantum wire\neffect,\" Appl. Phys. Lett., 58, 856 (1991).","L. Brus, Light emission in silicon from physics to devices, D. Lockwood\n(Ed.), Academic Press, New York, (1998) p.303.","S. Ossicini, Light emitting silicon for microphotonics, S. Ossicini, L.\nPavesi, F.Priolo (Ed.), Springer, Berlin (2003) p.123.","G. T. Reed and A. P. Knights (Ed.), Silicon Photonics, Wiley-Interscience\n(2008).","L. Pavesi, L. Dal Negro, C. Mazzoleni, G. Franzó, F. Priolo, \"Optical gain\nin silicon nanocrystals,\" Nature, 408, 440 (2000).","T. S. Iwayama, K. Fujita, S. Nakao, K. Saitoh, T. Fujita, N. Itoh, \"Visible\nphotoluminescence in Si+‐implanted silica glass,\" J. Appl. Phys., 75, 7779\n(1994).","T. S. Iwayama, S. Nakao, K. Saitoh, Visible photoluminescence in Si+‐\nimplanted thermal oxide films on crystalline Si Appl. Phys. Lett., 65,\n1814 (1994).","J. F. Ziegler, Ion Implantation Technology, J. F. Ziegler (Ed.),\nNorth-Holland, Amsterdam (1992) p.1.\n[10] P. D. Townsend, P. J. Chandler and L. Zhang, Optical Effects of Ion\nImplantation, Cambridge University Press, Cambridge (1994).\n[11] K. S. Min, K. V. Shcheglov, C. M. Yang, H. A. Atwater, M. L.\nBrongersma, A. Polman, \"Defect‐related versus excitonic visible light\nemission from ion beam synthesized Si nanocrystals in SiO2,\" Appl. Phys.\nLett., 69, 2033 (1996).\n[12] P. Mutti, G. Ghislotti, S. Bertoni, L. Bonoldi, G. F. Cerofolini, L. Meda, E.\nGrilli, M. Gruzzi, \"Room‐temperature visible luminescence from silicon\nnanocrystals in silicon implanted SiO2 layers,\" Appl. Phys. Lett., 66, 851\n(1995).\n[13] J. F. Ziegler, J. P. Biersack, U. L. Littmark, the Stopping and Range of\nIons in Solids, Pergamon, New York (1985).\n[14] L. Skuja Optically active oxygen-deficiency-related centers in amorphous\nsilicon dioxide,\" J. Non-Cryst. Solids, 239, 16 (1998).\n[15] T. S. Iwayama, T. Hama, D. E. Hole, I. W. Boyd, \"Characteristic\nphotoluminescence properties of Si nanocrystals in SiO2 fabricated by ion\nimplantation and annealing,\" Solid State Elec., 45, 1487 (2001).\n[16] Defects in SiO2 and Related Dielectrics: Science and Technology, G.\nPacchioni, L. Skuja, D. L. Griscom (Ed.), Kluwer Academic Publishers\n(2001).\n[17] T. S. Iwayama, Y. Terao, A. Kamiya, M. Takeda, S. Nakao, K. Saitoh,\n\"Correlation of Microstructure and photoluminescence for\nnanometer-sized Si crystals formed in an amorphous SiO2 matrix by ion\nimplantation, Nanostruct. Mater. 5, 307 (1995)."]}

It is well known that Si ion implantation into SiO 2 and subsequent high-temperature anneals induce the formation of embedded luminescent Si nanocrystals. In this work, the potentialities of rapid thermal annealing to enhance the photoluminescence intensity have been investigated. Ion implantation was used to synthesize specimens of SiO 2 containing excess Si with different concentrations. Si precipitation to form nanocrystals in implanted samples takes place with a conventional furnace anneal. The photoluminescence intensity and the peak energy of emission from Si nanocrystals depend on implanted ion dose. Moreover, the luminescence intensity is strongly enhanced with a rapid thermal annealing prior to a conventional furnace anneal. The luminescence intensity, however, decreases when rapid thermal annealing follows conventional furnace annealing. It is found that the order of heat treatment is an important factor in intensities of the luminescence and that the luminescence peak energy is found to be dependent, but only by a small factor, on the thermal history of specimens. Enhancement is found to be typical for low dose samples. Furthermore, the observation that the prolonged anneal induces saturation and a blue shift of the luminescence strongly indicates the emission is not simply due to electron–hole recombination inside the Si nanocrystals. Based on our experimental results, we discuss the mechanism for the enhancement of the photoluminescence, together with the mechanism of photoemission.

The behavior of relative intensity noise of GaInNAsSb 1300-nm-range vertical-cavity surface-emitting lasers (VCSELs) is presented for the first time. The relative intensity noise drastically increases beyond a critical optical feedback. It was theoretically and experimentally found that the increase of relaxation oscillation frequencies was effective for the sensitivity of the optical feedback in the single-mode long-wavelength VCSELs. In our experiment, the critical feedback levels were -32 and -29 dB when frequencies were 4.0 and 5.8 GHz. This result is in good agreement with a theory.

Potentialities of rapid thermal annealing to enhance the photoluminescence emission of Si nanocrystals in SiO2 have been investigated. Ion implantation was used to synthesize specimens of SiO2 containing excess Si with different concentrations. Si precipitation to form nanocrystals in implanted samples takes place with a conventional furnace anneal. The photoluminescence intensity and the peak energy of emission from Si nanocrystals depend on implanted ion fluence. Moreover, the luminescence intensity is strongly enhanced with a rapid thermal anneal prior to a conventional furnace anneal. The luminescence intensity, however, decreases with a rapid thermal anneal following a conventional furnace anneal. It is found that the order of heat treatment is an important factor in intensities of the luminescence. Moreover, the luminescence peak energy is found to be dependent, but a little, on thermal history of specimens. Based on our experimental results, we discuss about the mechanism of an enhancement of the photoluminescence, together with the mechanism of photoemission from encapsulated Si nanocrystals produced in a SiO2 matrix by ion implantation and annealing.

1-Propanethiol (CH3CH2CH2SH) was connected with O-polar zinc oxide (ZnO) surfaces toward biofunctional devices. X-ray photoelectron spectroscopy (XPS) measurement revealed that the S O bonds were formed between 1-propanethiol and ZnO layers. Although the surface coverage of the molecule is less than a few percent, 1-propanethiol/ZnO structures were stable even at thermal treatment of 400 °C.

1.3-/spl mu/m-range GaInNAsSb vertical-cavity surface-emitting lasers (VCSELs) with the doped mirror were investigated. GaInNASb active layers that include a small amount of Sb can be easily grown in a two-dimensional manner as compared with GaInNAs due to the suppression of the formation of three-dimensional growth in MBE growth. The authors obtained the lowest J/sub th/ per well (150 A/cm/sup 2//well) for the edge-emission type lasers due to the high quality of GaInNAsSb quantum wells. Using this material for the active media, the authors accomplished the first continuous wave operation of 1.3-/spl mu/m-range GaInNAsSb VCSELs. For the reduction of the threshold voltage and the differential resistance, they used the doped mirror grown by metal-organic chemical vapor deposition (MOCVD). By three-step growth, they obtained 1.3-/spl mu/m GaInNAs-based VCSELs with the low threshold current density (3.6 kA/cm/sup 2/), the low threshold voltage (1.2 V), and the low differential resistance (60 /spl Omega/) simultaneously for the first time. The back-to-back transmission was carried out up to 5 Gb/s. Further, the uniform operation of 10-ch VCSEL array was demonstrated. The maximum output power of 1 mW was obtained at 20/spl deg/C by changing the reflectivity of the front distributed Bragg reflector mirror. GaInNAsSb VCSELs were demonstrated to be very promising material for realizing the 1.3-/spl mu/m signal light sources, and the usage of the doped mirror grown by MOCVD is the best way for 1.3-/spl mu/m VCSELs.

A possible mechanism for the photoemission from Si nanocrystals in an amorphous SiO 2 matrix fabricated by ion implantation is reported. We have measured the implantation dose dependence on the photoluminescence behavior images of Si nanocrystals in SiO 2 layers, fabricated by ion implantation and a subsequent annealing step. After annealing, a photoluminescence band, peaking just below 1.7 eV, was observed. The peak energy of the photoluminescence was found to be affected by the dose of implanted Si ions, but to be independent of annealing time. We also present experimental results of high-resolution transmission electron microscopy (HRTEM) for each annealing step. The size of Si nanocrystals increases with increasing ion dose and annealing time. These results indicate that whilst the excitation photons are absorbed by Si nanocrystals, the emission is not simply due to electron–hole recombination inside the Si nanocrystals, but is related to the presence of some kind of defects, most likely located at the interface between the Si nanocrystals and the SiO 2 , for which the characteristic energy levels are affected by cluster–cluster interactions.

Persistent sensitivity to noxious and innocuous somatic stimuli results from peripheral nerve injury. Following chronic constriction injury (CCI) of the sciatic nerve in the rat, the hind paw ipsilateral to the injury displays significantly decreased response latencies to a noxious heat stimulus (thermal hyperalgesia), compared with the contralateral uninjured paw. The ligated paw also shows increased lifting and duration of lifting from a cooled (4 +/- 1 degrees C) surface. To characterize the peripheral nerve component of increased sensitivity to cold, CCI rats were systemically injected with the potent capsaicin analog resiniferatoxin (RTX). Twenty-four hours following RTX injection response latencies to noxious heat were significantly increased for both the ligated and unligated hind paws. In addition, increased responsiveness of the ligated paw to the cold surface was significantly attenuated. The results demonstrate that the enhanced responsiveness to cold and heat following a CCI are mediated in part by RTX-sensitive primary afferents.

Intraplantar injection of 0.4% formalin into the rat hind paw leads to a biphasic nociceptive response; an 'acute' phase (0-15 min) and 'tonic' phase (16-120 min), which is accompanied by significant phosphorylation of extracellular signal-regulated kinase (ERK)1/2 in the contralateral striatum at 120 min post-formalin injection. To uncover a possible relationship between the slow-onset substance P (SP) release and increased ERK1/2 phosphorylation in the striatum, continuous infusion of SP into the striatum by reverse microdialysis (0.4 μg/mL in microdialysis fiber, 1 μL/min) was performed to mimic volume neurotransmission of SP. Continuous infusion for 3 h of SP reduced the duration of 'tonic' phase nociception, and this SP effect was mediated by neurokinin 1 (NK1) receptors since pre-treatment with NK1 receptor antagonist CP96345 (10 μM) blocked the effect of SP infusion. However, formalin-induced 'tonic' phase nociception was significantly prolonged following acute injection of the MAP/ERK kinase 1/2 inhibitor PD0325901 (100 pmol) by microinjection. The coinfusion of SP and PD0325901 significantly increased the 'tonic' phase of nociception. These data demonstrate that volume transmission of striatal SP triggered by peripheral nociceptive stimulation does not lead to pain facilitation but a significant decrease of tonic nociception by the activation of the SP-NK1 receptor-ERK1/2 system. Noxious stimulation induces a slow-onset substance P (SP) release as a volume transmitter, activating extra-synaptic NK1 receptors, and evokes phosphorylation of extracellular signal-regulated kinase (ERK) 1/2. The SP-NK1-ERK1/2 system in the striatum decreases tonic nociception.

A lack of efficacy of some analgesic drugs has been previously described in rats with neuropathic spinal cord injury (SCI) pain. It has been suggested that repeated dosing in these animals over time may eventually lead to efficacy. However, it is also possible that efficacy may diminish over time with repeated dosing. This study evaluated the efficacy of various drugs upon repeated dosing over time in a rat model of SCI pain. Four weeks following an acute spinal cord compression at the mid-thoracic level, rats developed decreased hind paw withdrawal threshold, suggestive of below level neuropathic hypersensitivity. Either cannabinoid (CB) receptor agonist CP 55,940, the anticonvulsant carbamazepine or gabapentin, the antidepressant amitriptyline or vehicle was administered over a period of 7 days. Neither carbamazepine nor amitriptyline demonstrated efficacy either after a single or repeated dosing. Beginning with a 50% efficacious dose of gabapentin, the effect of gabapentin in SCI rats neither increased nor decreased over the treatment period. The antinociceptive effect of CP 55,940 was maintained for the entire treatment period, which was mediated by CB1 but not CB2 receptors. The current data suggest that sustained antinociception can be obtained with some drugs in rats with neuropathic SCI pain. Furthermore, the current data do not substantiate the notion that repeated treatment with initially ineffective drugs will eventually lead to efficacy; treatments that are not acutely effective are unlikely to demonstrate clinical efficacy.

To study the electronic structures of quantum dots in the framework of self-interaction-free including three dimensional effects, we adopt the theory of nonlocal effective potential introduced by Kohn and Sham [#!ks65!#]. For utilizing the advantageous point of the real space (3D) mesh method to solve the original nonlinear and nonlocal Hartree-Fock-Kohn-Sham (HFKS)-equation, we introduce a linearization of the equation in the local form by introducing the local Coulomb potentials which depend on explicitly the two single particle states. In practice, for solving the local form HFKS-equation, we use the Car-Parrinello-like relaxation method and the Coulomb potentials are obtained by solving the Poisson equation under proper boundary conditions. Firstly the observed energy gap between triplet- and singlet-states of N = 4 in DBS [#!tarucha96!#] is discussed to reproduce the addition energies and chemical potentials depending the magnetic field. Next the coupling between two-quantum dots in TBS [#!aht97!#] is studied by adding the square barrier between two dots. The spin-degeneracy [#!aht97!#] measured in gate-voltage depending on magnetic field is well reproduced in the limit of small mismatch. Finally, the electronic states in the ring structure are calculated and discussed how the ring size and magnetic field affect to the structures.

We have measured the implantation dose dependence as well as the oxidation effect of the photoluminescence behaviour of Si nanocrystals in SiO2 layers fabricated by ion implantation and a subsequent annealing step. After annealing at high temperature, a characteristic photoluminescence band, peaking just below the 1.7 eV was observed. The peak energy and the intensity of the photoluminescence were found to be affected by the dose of implanted Si ions, but to be independent of annealing time and excitation photon energy. We also present experimental results of an oxidation induced continuous peak energy shift of the photoluminescence peak up to around 1.8 eV. This peak energy, however, was found to return to its previous position with re-annealing. These results indicate that whilst the excitation photons are absorbed by Si nanocrystals, the emission is not simply due to electron–hole recombination inside the Si nanocrystals, but is related to the presence of defects, most likely located at the interface between the Si nanocrystals and the SiO2, for which the characteristic energy levels are affected by cluster–cluster interactions or the roughness of the interface.

The NJL model is formulated on the light cone. Using the 1/N expansion to solve the fermionic constraint, an effective 4-fermi lagrangian is derived. Pionic properties are investigated using this lagrangian, and the formal equivalence to the equal-time formulation is demonstrated. Two regularization schemes in terms of light-cone variables are discussed: An extension of the 'invariant mass cut-off scheme', and a transverse momentum cut-off scheme. It is shown that the first one is equivalent to the covariant 3-momentum cut-off (dispersion cut-off) scheme in the equal-time formulation. As an application the structure function of the pion is studied in both regularization schemes., Comment: 48 pages, 5 figures

N-methyl-D-aspartate (NMDA) receptor activation is thought to initiate a cellular cascade of events in the spinal cord that leads to neuronal hyperactivation and exaggerated persistent pain behaviors. Previous studies have demonstrated that implantation of adrenal medullary tissue into the spinal subarachnoid space reduces abnormal pain behaviors such as hyperalgesia and allodynia, possibly by intervening in the NMDA hyperexcitability cascade. Histogranin is a 15-amino acid peptide possessing NMDA receptor antagonist activity that has been isolated from adrenal medullary tissue. The present study examined the ability of stable analog [Ser1]histogranin to reduce abnormal pain-related behaviors induced in rats by direct activation of spinal NMDA receptors. The intrathecal injection of NMDA (5.0, 10.0, 20.0 nmol) produced significant thermal and mechanical hyperalgesia and tactile allodynia in a dose-related fashion. [Ser1]histogranin injected intrathecally prior to NMDA injections dose dependently attenuated or completely blocked hyperalgesia and allodynia. In addition, [Ser1]histogranin administration following NMDA-induction of abnormal pain behaviors reversed these effects. These results demonstrate that a naturally derived adrenal medullary neuropeptide can prevent and reverse NMDA-mediated spinal hyperexcitability. The distinct profile and robust activity of [Ser1]histogranin suggest novel alternative approaches in the management of pain and other CNS disorders involving abnormal excitatory neurotransmission.

Spinally projecting neurons of the ventromedial medulla (VMM) compose an important efferent pathway for the modulation of nociception. These neurons receive a substantial gamma-aminobutyric acid (GABA)-ergic input, but the GABA receptor that mediates this input is unknown. This study examined the distribution of GABA(A) receptor alpha1 and alpha3 subunits in serotonergic and nonserotonergic neurons of the VMM that project to the dorsal horn in the rat. A pledget of Gelfoam soaked in Fluoro-Gold was placed at the thoracolumbar junction of the spinal cord to label spinally projecting neurons. Alternate sections of the medulla were then incubated with a mixture of antisera to either serotonin and the alpha1 subunit, or to serotonin and the alpha3 subunit of the GABA(A) receptor. Nearly 30% of spinally projecting neurons in the VMM were immunoreactive for the alpha1 subunit. A similar percentage of spinally projecting neurons in the VMM were immunoreactive for the alpha3 subunit, although diffuse cellular labeling combined with intense staining of processes in the neuropil precluded a rigorous semi-quantitative estimation of this population. No alpha1-subunit-immunoreactive neurons colocalized serotonin. In contrast, serotonergic neurons were immunoreactive for the alpha3 subunit. However, these double-labeled neurons were a modest percentage of the serotonergic population. A small percentage of spinally projecting serotonergic neurons was immunoreactive for the alpha3 subunit. These results suggest that significant numbers of spinally projecting serotonergic and nonserotonergic neurons of the VMM possess GABA(A) receptors that differ in their respective subunit compositions and that both classes of neurons may mediate the antinociception produced by the microinjection of GABA(A) receptor antagonists in the VMM.

Chronic pain may result from hyperexcitability following activation of spinal NMDA receptors. A naturally-derived mammalian peptide, histogranin, may possess NMDA antagonist activity. This study explored the possibility that stable analog [Ser1]Histogranin (SHG) could reduce chronic pain. Neuropathic pain was induced using the chronic constriction injury model (CCI). Intrathecal injection of SHG markedly attenuated the hyperalgesia and allodynia resulting from CCI, nearly normalizing responses. These results suggest that the natural peptide histogranin may be a novel adjunct in neuropathic pain management.

Excessive activation of N-methyl-D-aspartate (NMDA) receptors in the spinal cord consequent to peripheral injury has been implicated in the initiation of neuropathologic events leading to a state of chronic hyperexcitability and persistence of exaggerated sensory processing. In other CNS disease or injury states, NMDA-mediated neurotoxic damage is associated with a loss of NMDA receptors, and outcome may be improved by agents reducing NMDA activation. Previous findings in our laboratory have demonstrated that the transplantation of adrenal medullary tissue into the spinal subarachnoid space can alleviate sensory abnormalities and reduce the induction of a putative nitric oxide synthase consequent to peripheral nerve injury. In order to determine changes in NMDA receptor expression in the spinal cord following peripheral nerve injury and adrenal medullary grafting, NMDA receptor binding using a high-affinity competitive NMDA receptor antagonist, CGP-39653, and NMDAR1 subunit distribution using immunocytochemistry were investigated. Two weeks following peripheral nerve injury by loose ligation of the right sciatic nerve, either adrenal medullary or striated muscle (control) tissue pieces were implanted in the spinal subarachnoid space. Binding studies revealed a marked reduction in [3H]CGP-39653 binding at L4-L5 levels ipsilateral to peripheral nerve injury in control transplanted animals. In contrast, NMDA binding was normalized in adrenal medullary grafted animals. In addition, NMDAR1 immunoreactivity was reduced in both the dorsal horn neuropil and motor neurons of the ventral horn in animals with peripheral nerve injury, while levels in adrenal medullary grafted animals appeared similar to intact controls. These results suggest that adrenal medullary transplants reduce abnormal sensory processing resulting from peripheral injury by intervening in the spinal NMDA-excitotoxicity cascade.

The removal of dioxin was studied by a pilot plant with a fabric bag filter system and selective catalyst reduction (SCR) system, which was equipped at a MSW incineration plant. It was confirmed that the removal efficiency of dioxin was 93.7∼98.2% with the fabric bag filter system and 90.5∼97.4% with the SCR system : the emission of dioxin decreased less than 0.1ng/Nm 3 -TEQ by the association system.

Light-induced degradation and light-induced degradation after current-induced degradation of several types of a-Si solar cells were compared in order to investigate the difference between current-induced degradation and light-induced degradation. Very little difference in the efficiency after long-term light irradiation is observed between samples which were degraded by light- after current-induced degradation and those which were degraded by light only. Little difference in the collection efficiency spectra and the depth profiles of the DICE (dynamic inner collection efficiency) is also observed between the cells degraded by these two processes. The possibility of applying the current-induced degradation method to the stabilization of a-Si solar modules is indicated.

Structural properties for CuInSe2 films formed by two methods, (a) three-source co-evaporation and (b) selenization of Cu/In/Se-stacked layer, were studied using X-ray diffraction, Raman scattering and SEM imaging. It is found that films by co-evaporation show stronger (112) orientation than the selenization films and A1 mode peak in Raman spectra is seen for selenized films even with a ratio of Cu/In < 0.6 in which composition the peak relating to A1 mode disappeas in co-evaporated films. A conversion efficiency of 10.5% was obtained for a CuInSe2 solar cell using the co-evaporated film.

The grain boundary premelting temperature (GBPMT) T m in thin foils of 99.99 mass% copper bicrystals deformed in tension to a strain of 0.4 increased from approximately 0.5 T M up to near the bulk melting point T M with increasing oxidation time. The GBPMT T m in thin foils of the bicrystal whose grain boundary plane was parallel to active screw dislocations was lower than that to active edge dislocations. The difference between the GBPMT in 99.99 and 99.9999 mass% copper polycrystals were not so significant. The difference between the GBPMT T m (Al)[ ≑ T M (Al)] of aluminum bicrystals and the T m (Cu)[ ≑ 0.5T M (Cu)] of copper bicrystals depends upon the difference between the properties of the corresponding oxide films and would probably be related to the difference in the elastic anisotropy between them. Plastic strain would decrease the GBPMT at least in copper.

The effects of clonidine on substance P (SP) binding was investigated using rat brain and spinal cord membrane preparations preincubated with various concentrations of clonidine. [3H]SP specific binding in the spinal cord was significantly decreased with 10(-4) M clonidine, but no effect on binding was seen in the brain. Scatchard analysis of SP binding indicated that Bmax was significantly depressed without changing the affinity. The mechanism of clonidine-induced analgesia includes a spinal neural component and action on the SP receptors.

Dark current‐voltage (J‐V) characteristics of p‐i‐n a‐Si solar cells are studied to clarify the effect of the p/i interface layer on the open‐circuit voltage (Voc). It is shown that the recombination current in the p/i interface region is predominant in the a‐Si solar cells with an i‐layer thickness of less than 200 nm and has a great effect on the dark‐current transport in the solar cells. It is also shown that the current transport of the cells with the p/i interface layer of constant band gap of a thickness of more than 14 nm is effectively the same as that of a cell in which the band gap of the whole i layer is equal to that of the interface layer. A model in which the dark current of the cell consists of the recombination current at the p/i interface and the recombination current in the bulk region of the i layer is proposed. Using this model, the Voc degradation for the a‐Si solar cells with the p/i interface layer is shown to be due to the defects generated in the i layer.

Inserting an endoscope into colon requires very technical procedure and it is difficult in some cases even for experienced doctors. Although active colonoscopes have been researched, these instruments are still in the development stage. Mechanisms for this application are required to be soft enough not to injure the colon wall and being deformable enough to adapt to the curves of the colon. In addition, the mechanisms must generate distributed force adequate for traveling. These requirements are difficult to be satisfied using conventional mechanisms and actuators. We have designed and developed two types of new driving mechanism using pneumatic rubber actuators and made their feasibility tests. One mechanism is "thin tube wave generator": introducing pulse pneumatic flows to a thin rubber tube causes traveling deformation waves on the tube surface, which drives an object placed on the tube. The other mechanism is "round bubbler": a rubber tube which has four chambers in it is wound around the colonoscope to cause traveling deformation waves on the scope surface by sending pneumatic pressures to each chamber sequentially. In this paper, first, we discuss the driving mechanisms, pneumatic control systems, and basic characteristics of these two mechanisms. Then, based on the basic experimental discussions, we fabricated special rubber mechanisms to fit around a conventional colonoscope, and conducted insertion experiments using an intestinum model and an existing colonoscope under various conditions. The experimental results are very promising

Bio applications of compound semiconductors are of great interest and much attention has been paid to ZnO-based materials because of their multifunctional properties. Toward the biologically sensitive field effect transistor (BioFET) (Schoning and Poghossian, 2002), biochemical functionalization remains a fundamental issue. For instance, for the realization of glucose sensor, glucose specifically sensitive enzymes, such as glucose oxidase, need to be immobilized via spacer molecules. In this work, spacer molecule modified ZnO surface as well as ZnMgO alloys were characterized by X-ray photoelectron spectroscopy (XPS).

The reliability of oxide confined 850 nm VCSELs for 10 Gb/s operation was investigated. The median life with criteria of 2 dB decrease of output power at environmental temperature of 25/spl deg/C was over 10 million hours.