Search

Super-Kamiokande has been searching for neutrino bursts characteristic of core-collapse supernovae continuously, in real time, since the start of operations in 1996. The present work focuses on detecting more distant supernovae whose event rate may be too small to trigger in real time, but may be identified using an offline approach. The analysis of data collected from 2008 to 2018 found no evidence of distant supernovae bursts. This establishes an upper limit of 0.29 yr−1 on the rate of core-collapse supernovae out to 100 kpc at 90% C.L. For supernovae that fail to explode and collapse directly to black holes the limit reaches to 300 kpc.

In order to improve Super-Kamiokande's neutron detection efficiency and to thereby increase its sensitivity to the diffuse supernova neutrino background flux, 13 tons of $\rm Gd_2(\rm SO_4)_3\cdot \rm 8H_2O$ (gadolinium sulfate octahydrate) was dissolved into the detector's otherwise ultrapure water from July 14 to August 17, 2020, marking the start of the SK-Gd phase of operations. During the loading, water was continuously recirculated at a rate of 60 m$^3$/h, extracting water from the top of the detector and mixing it with concentrated $\rm Gd_2(\rm SO_4)_3\cdot \rm 8H_2O$ solution to create a 0.02% solution of the Gd compound before injecting it into the bottom of the detector. A clear boundary between the Gd-loaded and pure water was maintained through the loading, enabling monitoring of the loading itself and the spatial uniformity of the Gd concentration over the 35 days it took to reach the top of the detector. During the subsequent commissioning the recirculation rate was increased to 120 m$^3$/h, resulting in a constant and uniform distribution of Gd throughout the detector and water transparency equivalent to that of previous pure-water operation periods. Using an Am-Be neutron calibration source the mean neutron capture time was measured to be $115\pm1$ $\mu$s, which corresponds to a Gd concentration of $111\pm2$ ppm, as expected for this level of Gd loading. This paper describes changes made to the water circulation system for this detector upgrade, the Gd loading procedure, detector commissioning, and the first neutron calibration measurements in SK-Gd., Comment: 37 pages, 19 Figures, Accepted for publication in Nucl. Instrum. Meth. A

We present the development of neutron-tagging techniques in Super-Kamiokande IV using a neural network analysis. The detection efficiency of neutron capture on hydrogen is estimated to be 26%, with a mis-tag rate of 0.016 per neutrino event. The uncertainty of the tagging efficiency is estimated to be 9.0%. Measurement of the tagging efficiency with data from an Americium-Beryllium calibration agrees with this value within 10%. The tagging procedure was performed on 3,244.4 days of SK-IV atmospheric neutrino data, identifying 18,091 neutrons in 26,473 neutrino events. The fitted neutron capture lifetime was measured as 218±9 μs. We present the development of neutron-tagging techniques in Super-Kamiokande IV using a neural network analysis. The detection efficiency of neutron capture on hydrogen is estimated to be 26%, with a mis-tag rate of 0.016 per neutrino event. The uncertainty of the tagging efficiency is estimated to be 9.0%. Measurement of the tagging efficiency with data from an Americium-Beryllium calibration agrees with this value within 10%. The tagging procedure was performed on 3,244.4 days of SK-IV atmospheric neutrino data, identifying 18,091 neutrons in 26,473 neutrino events. The fitted neutron capture lifetime was measured as 218 \pm 9 \mu s.

The Super-Kamiokande detector can be used to search for neutrinos in time coincidence with gravitational waves detected by the LIGO-Virgo Collaboration (LVC). Both low-energy ($7-100$ MeV) and high-energy ($0.1-10^5$ GeV) samples were analyzed in order to cover a very wide neutrino spectrum. Follow-ups of 36 (out of 39) gravitational waves reported in the GWTC-2 catalog were examined; no significant excess above the background was observed, with 10 (24) observed neutrinos compared with 4.8 (25.0) expected events in the high-energy (low-energy) samples. A statistical approach was used to compute the significance of potential coincidences. For each observation, p-values were estimated using neutrino direction and LVC sky map ; the most significant event (GW190602_175927) is associated with a post-trial p-value of $7.8\%$ ($1.4\sigma$). Additionally, flux limits were computed independently for each sample and by combining the samples. The energy emitted as neutrinos by the identified gravitational wave sources was constrained, both for given flavors and for all-flavors assuming equipartition between the different flavors, independently for each trigger and by combining sources of the same nature., Comment: 16 pages, 5 figures. v2: adding corrections from The Astrophysical Journal review

A search for neutrinos produced in coincidence with Gamma-Ray Bursts(GRB) was conducted with the Super-Kamiokande (SK) detector. Between December 2008 and March 2017, the Gamma-ray Coordinates Network recorded 2208 GRBs that occurred during normal SK operation. Several time windows around each GRB were used to search for coincident neutrino events. No statistically significant signal in excess of the estimated backgrounds was detected. The $\bar\nu_e$ fluence in the range from 8 MeV to 100 MeV in positron total energy for $\bar\nu_e+p\rightarrow e^{+}+n$ was found to be less than $\rm 5.07\times10^5$ cm$^{-2}$ per GRB in 90\% C.L. Upper bounds on the fluence as a function of neutrino energy were also obtained., Comment: 29 pages, 16 figures, 5 tables, accepted by PTEP

We have searched for proton decay via p→e+π0 and p→μ+π0 modes with the enlarged fiducial volume data of Super-Kamiokande from April 1996 to May 2018, which corresponds to 450 kton·years exposure. We have accumulated about 25% more livetime and enlarged the fiducial volume of the Super-Kamiokande detector from 22.5 kton to 27.2 kton for this analysis, so that 144 kton·years of data, including 78 kton·years of additional fiducial volume data, has been newly analyzed. No candidates have been found for p→e+π0 and one candidate remains for p→μ+π0 in the conventional 22.5 kton fiducial volume and it is consistent with the atmospheric neutrino background prediction. We set lower limits on the partial lifetime for each of these modes: τ/B(p→e+π0)>2.4×1034 years and τ/B(p→μ+π0)>1.6×1034 years at 90% confidence level.

Summary Background & aims The associations between dietary magnesium intake and stroke and coronary heart disease (CHD) incidences are inconsistent and not established in Asian. We aimed to determine the association between dietary magnesium intake and the risk of stroke and CHD in a Japanese population. Subjects/Methods We studied 85,293 Japanese subjects by questionnaire at baseline (age 45–74 years, without cardiovascular disease or cancer in 1995 and 1998 for Cohorts I and II, respectively). The participants were followed until the end of 2009 and 2010 in Cohorts I and II, respectively. Dietary magnesium intake was estimated from a self-administered 138-item food-frequency questionnaire. Results After 1,305,738 person-years of follow-up, 4110 strokes and 1283 cases of CHD were documented. The multivariable-adjusted hazard ratios (HRs, 95% confidence intervals, 95%CIs) of CHD for the fourth and fifth quintiles of dietary magnesium intake were 0.70 (0.50–0.99) and 0.66 (0.44–0.97) in men (P for trend = 0.036), respectively, and third quintile of dietary magnesium intake was 0.61 (0.39–0.96) in women (P for trend = 0.241), compared with the lowest quintile in men and women. We observed no decreased risks of incident stroke in men or women with higher dietary magnesium intakes. Conclusions Higher dietary magnesium intake was associated with a reduced risk of CHD in Japanese men.

A finding between dietary pattern and cancer may provide visions beyond the assessment of individual foods or nutrients. We examined the influence of dietary pattern with colorectal cancer (CRC) among a Japanese population.A total of 93,062 subjects (43,591 men, 49,471 women) who participated in the Japan Public Health Center-based Prospective Study were followed from 1995-1998 to the end of 2012, during which 2482 cases of CRC (1514 men, 968 women) were newly identified. Dietary data was obtained from a validated food-frequency questionnaire between 1995 and 1998.Three dietary pattern was derived from principal components factor: prudent, westernized, and traditional pattern. After controlled for potential confounders, the prudent pattern showed a decreased association of CRC risk in men (HR for highest quintile vs lowest: 0.85; 95% CI: 0.72-1.00; P trend0.05), slightly more strongly with distal colon cancer (P trend0.05); but an increased risk of rectal cancer in women (P trend0.05). The westernized pattern showed a significant positive linear trend for colon (P trend0.05) and distal cancer (P trend0.05) in women. There was no apparent association of traditional Japanese dietary pattern on the overall or any specific sites risk of CRC.A prudent dietary pattern showed an inverse association with CRC risk in men, and a westernized pattern was related with a higher risk of colon and distal cancer in women.

The paper presents a method for measuring photosynthetic photon flux density (PPFD) using a commercially available digital camera. PPFD is one of the critically important measurements to control photosynthetic reaction of plants. Conventionally a dedicated quantum sensor is used to measure PPFD. A quantum sensor, however, can measure PPFD of a target point at once. Thus considerable cost and labor would be consumed if the quantum sensors were introduced for managing photosynthetic reaction of numerous plants in a large greenhouse for growing commercial crops. In order to solve the problem, we propose a method for measuring PPFD using a commercially available digital camera. The method estimates spectral irradiance of daylight, fluctuating hour by hour according to weather condition changes, on the basis of the color information of a reference object in an image captured by a digital camera. Then PPFD is derived from the estimated spectral irradiance. For practical use, plural reference objects are placed in a plant community and captured as an image. PPFDs at the positions of the reference objects in the captured image are simultaneously measured. We believe that proposed method is useful in real cultivation. We conducted experiments in outdoor environment. During the experiments, a Nikon digital SLR camera D300 and a white plaster ball as a reference object were used. We finally confirmed that the average error rate of PPFD measurements by this method was 2.58%, and the maximum was within 5% which is equivalent to the accuracy of the quantum sensor on the market.

Aims Coping strategies may be significantly associated with health outcomes. This is the first study to investigate the association between baseline coping strategies and cardiovascular disease (CVD) incidence and mortality in a general population cohort. Methods and results The Japan Public Health Center-based prospective Study asked questions on coping in its third follow-up survey (2000–04). Analyses on CVD incidence and mortality included 57 017 subjects aged 50–79 without a history of CVD and who provided complete answers on approach- and avoidance-oriented coping behaviours and strategies. Cox regression models, adjusted for confounders, were used to determine hazard ratios (HRs) according to coping style. Mean follow-up time was 7.9 years for incidence and 8.0 years for mortality. The premorbid use of an approach-oriented coping strategy was inversely associated with incidence of stroke (HR = 0.85; 95% CI, 0.73–1.00) and CVD mortality (HR = 0.74; 95% CI, 0.55–0.99). Stroke subtype analyses revealed an inverse association between the approach-oriented coping strategy and incidence of ischaemic stroke (HR = 0.79; 95% CI, 0.64–0.98) and a positive association between the combined coping strategy and incidence of intra-parenchymal haemorrhage (HR = 2.03; 95% CI, 1.01–4.10). Utilizing an avoidance coping strategy was associated with increased mortality from ischaemic heart disease (IHD) only in hypertensive individuals (HR = 3.46; 95% CI, 1.07–11.18). The coping behaviours fantasizing and positive reappraisal were associated with increased risk of CVD incidence (HR = 1.24; 95% CI, 1.03–1.50) and reduced risk of IHD mortality (HR = 0.63; 95% CI, 0.40–0.99), respectively. Conclusion An approach-oriented coping strategy, i.e. proactively dealing with sources of stress, may be associated with significantly reduced stroke incidence and CVD mortality in a Japanese population-based cohort.

Background and aims Higher intake of fish or n-3 polyunsaturated fatty acids (PUFAs) has been associated with reduced risk of coronary heart disease (CHD). However, it is unclear whether increased blood levels of n-3 PUFAs are associated with reduced risk of CHD in the Japanese population. Methods The relationship between circulating levels of n-3 PUFAs (eicosapentaenoic acid + docosapentaenoic acid + docosahexaenoic acid) and risk of CHD was examined in a nested case-control study among participants in the Japan Public Health Center (JPHC)-based Study Cohort. Plasma n-3 PUFA phospholipid levels were measured at baseline by gas chromatography in 209 cases with CHD and 418 controls matched for sex, age, date of blood draw, time elapsed since last meal before blood collection, and study location. The CHD cases (n = 209) comprised 168 cases of myocardial infarction and 41 of sudden cardiac death, otherwise classified as 157 non-fatal and 52 fatal coronary events, respectively. Mean duration of follow-up was 13.5 years. Results Multivariate conditional logistic analysis showed no significant association between n-3 PUFAs and risk of total CHD. The odds ratio (OR) for the highest versus lowest quartiles of plasma n-3 PUFAs was 0.79 (95% confidence interval [95% CI]: 0.41–1.51, p for trend = 0.51). Subtype analysis of CHD revealed that the multivariate ORs for the highest versus lowest quartiles for n-3 PUFAs were 0.91 (95% CI: 0.43–1.89, p for trend = 0.90) for myocardial infarction, 0.08 (95% CI: 0.01–0.88, p for trend = 0.04) for sudden cardiac death, 0.89 (95% CI: 0.42–1.89, p for trend = 0.97) for nonfatal coronary events, and 0.12 (95% CI: 0.02–0.75, p for trend = 0.03) for fatal coronary events. Conclusions Plasma n-3 PUFA levels were not associated with risk of total CHD but were inversely associated with risks of sudden cardiac death and fatal coronary events among middle-aged Japanese individuals.

Management of the olive fly using environmentally friendly methods includes strategies based on lure and kill and/or mass-trapping. Despite a wealth of studies related to the efficacy of different lure and kill and mass-trapping systems in several olive producing areas, there are few known regarding the performance of such systems in low input olive farms of the desert-like areas of the Middle East. The present study reports on the control of the olive fly using both lure and kill and mass-trapping devices in low-input farms in the region of Tubas, Palestine, between 2010 and 2012. The effect of environmental factors, such as elevation, on general patterns of olive fly infestation and the lure and kill system's performance was also studied. Our final goal included the development of a general strategy to produce organic olive oil using alternative olive fly control methods. Initially we used a commercially available lure and kill device, the Eco-Trap®. The Eco-Trap performed relatively well during the three years of study, significantly reducing olive fly damage levels. Eco-Trap effectiveness was more evident at elevation above 400 m, where damage in the region of Tubas was more intense than at lower elevations. In a subsequent trial we tested a low-cost mass-trapping device. This device demonstrated similar levels of protection to the one seen with the Eco-Trap. Results showed that lure and kill and mass-trapping tactics can be effectively applied in the region of Tubas, and that accessible devices can be adopted to reduce control costs. The results also showed differential levels of damage throughout the region, which were related to elevation above sea level. The possibility of applying a regional management concept throughout the area by a centralized organization, such as a farmer's union based on mass-trapping systems seems feasible and is discussed.

This paper presents an unsupervised learning-based object category formation and recognition method for mobile robot vision. Our method has the following features: detection of feature points and description of features using a scale-invariant feature transform (SIFT), selection of target feature points using one class support vector machines (OC-SVMs), generation of visual words using self-organizing maps (SOMs), formation of labels using adaptive resonance theory 2 (ART-2), and creation and classification of categories on a category map of counter propagation networks (CPNs) for visualizing spatial relations between categories. Classification results of dynamic images using time-series images obtained using two different-size robots and according to movements respectively demonstrate that our method can visualize spatial relations of categories while maintaining time-series characteristics. Moreover, we emphasize the effectiveness of our method for category formation of appearance changes of objects.

Effects of temperature on the morphological changes and degranulation were studied in stimulated neutrophils. Neutrophils were stimulated by formyl-methionyl-leucyl-phenylalanine (FMLP) and cytochalasin B at 4 degrees C, 20 degrees C and 37 degrees C, and they were processed for electron microscopy and biochemical assays of myeloperoxidase (MPO) activity. When neutrophils were stimulated at 4 degrees C, they did not show apparent morphological changes nor release MPO activity. In the cells stimulated at 20 degrees C, there were many cytoplasmic vacuoles, localization of MPO-positive granules adjacent to the cell membrane and around the vacuoles, MPO-positive materials in the cavity of the vacuoles, and slightly decreased numbers of granules. They released moderate amounts of MPO activity. The neutrophils at 37 degrees C showed formation of small vacuoles and canaliculi and a marked decrease in the number of MPO-positive granules indicative of degranulation, and they released increased amounts of MPO activity. There were MPO-positive materials on the membrane and in the cavity of the vacuoles. Ruthenium red staining showed that the vacuoles were formed open outside the cell. These results indicate that the vacuolar systems are involved in degranulation in stimulated neutrophils and that their formation is dependent on temperature.

The differentiation of monocytes was evaluated quantitatively by electron microscopy and was analyzed in relation to the clinical features of childhood acute lymphoblastic leukaemia (ALL). The monocyte cellular size increased and cell organellae became mature after a 72-h culture. Phagolysosome formation developed markedly- and the nucleus became circular--accompanied by chromatin deconcentration. The differentiation degree of the cell organellae was indexed and classified as mature by electron microscopy. The indexes of nuclear shape, chromatin deconcentration, cytoplasmonuclear ratio and vacuole formation increased with time. The total index increased linearly with time dependence. These results indicate that the ultrastructural parameters and indexes allowed a quantitative assessment of cell organellae and cellular differentiation of the monocyte. At the acute phase of ALL, the degrees of cell organnellae and cellular differentiation were significantly lower than the control. The above findings suggest that monocytes from children with ALL have impaired differentiation ability, which results in defective function of macrophages.

The ability of monocyte differentiation in childhood acute lymphoblastic leukaemia (ALL) was evaluated on the basis of the ultrastructure and peroxidase (PO) activity which could show the differentiation of cultured monocytes. In the control, PO activity limited to the granules decreased time-dependently during culture for 4 d, and was closely associated with the morphological development to macrophages. In childhood ALL, monocytes showed poor changes in both PO activity and morphological features during culture for 4 d compared to the control. Therefore, we conclude that monocyte to macrophage differentiation is impaired in childhood ALL.

The corrosion mechanisms of magnetic recording media in a high humidity environment were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and a metal elution test, where drops of nitric acid on the media surface were analyzed by inductively-coupled plasma mass spectrometry (ICP-MS) measurement (droplet-method). By observing SEM images, the corrosion on the media surface was found to have accelerated with longer exposure to the high humidity environment. Moreover, the cross-sectional TEM images proved that the lower NiP layer was invaded by moisture from the dented part of the magnetic layer due to its texture. In addition, the droplet-method analysis revealed that Co and Cr in the magnetic layer and Ni in the plated NiP layer were found to have eluted through the diamond-like carbon (DLC) film by drops due to nitric acid. The relation between the elution behavior of the elements and the corrosion process was clarified by adjusting the time the media surface was in contact with the nitric acid droplets. Based on these results, a model mechanism for corrosion behavior due to the moisture is proposed.

シカの個体群密度が数百年にわたって高密度で維持されている奈良公園では，植生の単純化によりカメムシ目の植食性昆虫トサカグンバイの寄主植物が事実上アセビしかない。このため，通常はアセビおよびネジキの2種の寄主植物間で季節的な寄主転換を行う本種が，奈良公園では寄主転換を行わない。長期間にわたるこのような生活環の違いがどのような遺伝的な変化をもたらしているのかを実験的に調べた。同じ条件下で羽化させた場合でも，寄主転換する京都個体群の個体は奈良個体群の個体より産卵数が少ない傾向があった。どちらの個体群の虫にとっても，ネジキはアセビよりもはるかに多い産卵数を達成できる質の良い寄主であったが，通常ネジキを利用している京都の虫にこの傾向がやや強かった。同じ条件で飼育したあとでも，京都の虫は奈良の虫と比較して，ネジキを強く選好する傾向がみられた。寄主転換を行う場合，特に寄主間の移動を行う世代で相対的な翅長が長くなることから，産卵数の減少はそれにともなうコストと考えられた。

Silk fibroin (SF) has been widely used in biomedical field for its high biocompatibility and mechanical properties. Scaffolds based on SF have been employed for tissue and bone regeneration. In this field electrospinning has proved an interesting and effective process for producing nanofibrous scaffolds usable for drug delivery, wound dressing, tissue engineering. Actually, the produced fibres have high specific surface area and high porosity with very small pore size. Therefore, the micro/nanofibres can simulate the extracellular matrix and enhance cell migration and proliferation. On the other hand, in the biomedical field, a single material hardly fulfills all the requirements of a specific biological function. Therefore, composites are designed to properly modify and tailor the materials properties according to the desired function. A common strategy consists in the preparation of composite scaffolds made from a biodegradable synthetic polymer and a natural material. In this study, composite nanofibrous scaffolds were obtained by electrospinning a solution containing regenerated Bombyx mori SF and poly(L-lactic acid) (PLLA) in a 1:1 weight ratio. Actually, PLLA is a biocompatible polymer used since a long time in many biomedical applications for its outstanding properties such as strength and controlled degradation. Optical and atomic force microscopy imaging has been employed to gather information on the length, thickness and weaving of the nanofibres in the material. Raman and IR spectroscopy have been employed to clarify the possible interactions between SF and PLLA in the composite scaffold and the structure modifications induced by these interactions. Raman and IR marker bands of the PLLA crystallinity were identified and their trend was followed as a function of the treatment. An analogous analysis was performed for the Raman and IR Amide modes of SF. The vibrational data showed that the electrospinning process caused a decrease in crystallinity in both SF and PLLA components, as also confirmed by thermoanalytical techniques such as Differential scanning calorimetry.

Wool keratin and silk fibroin are excellent biopolymers with outstanding properties that make them extremely valuable for biomedical and biotechnological applications. As proteins, fibroin and wool can be chemically modified at side chain groups of constituent amino acids, thus improving their properties according to the desired function. Among the chemical modifications techniques, graft copolymerization of vinyl monomers has been considered a powerful method to substantially improve some intrinsic fibre properties. Grafted fibres represent an interesting model for studying the possible structural changes induced by grafting and the interactions between the fibre matrix and the grafted polymer chains. In this study, wool and Bombyx mori and Anthaerea pernyi (Tussah) silk fibres were grafted with methacrylamide (MAA) and styrene (St) and were analysed by Raman spectroscopy to comparatively assess the reactivity of vinyl monomers towards silk fibroins and wool and to elucidate the interactions between fibres and polymers as well as the possible conformational changes caused by grafting. Upon grafting with both MAA and St, new bands (indicated with an asterisk, Figure 1) appeared with increasing intensity at increasing grafting yield. For B. mori and Tussah silk fibroin grafted with MAA, experimental and calculated spectra of the samples with the highest weight gains (97.6 and 71.4%, respectively) appeared different in several ranges, suggesting that silk fibroin and poly-MAA should be thermodynamically compatible rather than phase separated: intermolecular interactions seem to prevail and the changes in the niNH range indicated different H-bond interactions in the grafted samples. B. mori silk fibroin showed a conformational rearrangement towards a more disordered state. Conformational rearrangements seemed to involve poly-MAA as well, as suggested by the wavenumber shifts of some bands (indicated with a circle). Wool fibres showed less significant spectral changes, according to the lower grafting yield. With regards to grafting with St, experimental and calculated spectra showed less significant differences than after grafting with poly-MAA. No changes were observed in the niNH stretching range, suggesting the occurrence of interactions different from those observed with poly-MAA, probably of hydrophobic nature. The reactivity towards MAA and St was higher for B. mori and Tussah silk fibroin than for wool. Spectral changes reflected weight gain data. The spectroscopic marker that appeared the most useful to predict the MAA grafting yield was the I730/I644 intensity ratio; it was found to increase linearly with weight gain (R2 = 0.9). Analogous results were obtained for the I1602/I644 and I1002/I644 intensity ratios (St-grafting). Different interactions appeared to occur between the fibres and the two polymers.

Fluorescence microscopy is generally used for the research of biology, medical sciences and other life science fields. Especially, recent advances in laser technologies and in optical engineering have made it possible to investigate the nanoscale mechanisms of physiological and molecular biological processes and thus to extend its application to pathological and clinical investigations in therapeutic sciences. Furthermore, quantitative measurements of the small molecules, ions and proteins participated into the processes in living tissues, in vivo and in vitro, its movements, and locations can be observed with these optical technologies. Among them, the confocal microscopy was firstly invented for the purpose of visualization of such small-scale observations by using proper fluorescent molecules together with laser beams. Although contrast and resolution are degraded by strong scattering of the tissue preparations in the wide field conventional fluorescence microscope, the development of the confocal microscope can overcome some of the effects of scattering, since the detector pinhole rejects fluorescence from off-focus locations

A linkage map of Chinese cabbage (Brassica rapa) was constructed to localize the clubroot resistance (CR) gene, Crr3. Quantitative trait loci analysis using an F(3) population revealed a sharp peak in the logarithm of odds score around the sequence-tagged site (STS) marker, OPC11-2S. Therefore, this region contained Crr3. Nucleotide sequences of OPC11-2S and its proximal markers showed homology to sequences in the top arm of Arabidopsis chromosome 3, suggesting a synteny between the two species. For fine mapping of Crr3, a number of STS markers were developed based on genomic information from Arabidopsis. We obtained polymorphisms in 23 Arabidopsis-derived STS markers, 11 of which were closely linked to Crr3. The precise position of Crr3 was determined using a population of 888 F(2) plants. Eighty plants showing recombination around Crr3 locus were selected and used for the mapping. A fine map of 4.74 cM was obtained, in which two markers (BrSTS-41 and BrSTS-44) and three markers (OPC11-2S, BrSTS-54 and BrSTS-61) were cosegregated. Marker genotypes of the 21 selected F(2) families and CR tests of their progenies strongly suggested that the Crr3 gene is located in a 0.35 cM segment between the two markers, BrSTS-33 and BrSTS-78.

An all-epitaxial stacked ferroelectric capacitor, from the conductive plug to the top electrode, fabricated on a silicon substrate with a metal-oxide-semiconductor field-effect transistor is described. An SrRuO 3 /Pb(Zr,Ti)O 3 /Ir/TiN/Si(100) heteroepitaxial structure with epitaxially grown thin films on a silicon substrate had good crystallinity. Each thin film was oriented in the (100) direction with a cube-on-cube alignment on the silicon crystal lattice. The switching charges of fabricated epitaxial capacitors were around 36 μ C/cm 2 . The charge was less dependent on size for capacitors larger than 5 × 5 μ m.

Thin films made of (100)/(001)-oriented Pb(Zr, Ti)O3 (PZT) were deposited by liquid-delivery metal-organic chemical vapor deposition on Ir/MgAl2O4/SiO2/Si(100) substrates. For comparison, PZT thin films were also deposited on Ir/MgO(100) substrates. The X-ray Φ scan spectra for the (202) reflections revealed that the PZT films have four-fold symmetry. It indicates that the PZT films were epitaxially grown as a cube-on-cube structure on both substrates. The switchable polarization (Qsw) of the PZT capacitors on the silicon substrate was only 23 μ C/cm2 at 1.8 V; however, Qsw of PZT capacitors on MgO was 99 μ C/cm2. In the case of PZT films deposited on silicon, the volume fraction of (001)-oriented domains (which contribute to polarization switching) was 15.1% (calculated from an XRD pattern). This result is due to the lower Qsw of PZT capacitors on silicon. By piezoresponse-force microscopy, switchable and unswitchable domains could be identified by imaging color contrast, namely, (001) and (100) domains, respectively. Consequently, domain distribution of the PZT film on a silicon substrate indicates that the (001) domain exists in the (100) domain matrix.

Metallothionein (MT) is a small sulfhydryl-rich protein whose levels are elevated by various inducers of organelle stresses, such as nuclear stress (cisplatin), mitochondrial stress (antimycin A, 2,4-dinitrophenol) and lysosomal stress (paraquat). Although abnormal folding of protein in the endoplasmic reticulum (ER) causes ER stress, induction of MT synthesis by ER stress has never been investigated. In this study, we examined the induction of MT by an inducer of ER stress, tunicamycin (Tun), which induces ER stress by inhibiting N-linked glycosylation of protein in the ER. Administration of Tun (0.5-1.5 mg/kg, sc) increased hepatic MT levels in C57BL/6J mice (3.1-fold). The maximal increase in hepatic MT was observed 48-96 h after the administration of Tun (1.0 mg/kg). Expressions of MT-I, II and glucose-regulated protein 78 (Bip/GRP78), which is a molecular chaperone induced by ER stress, mRNA were also detected by administration of Tun. Thapsigargin (Thap), a generator of ER stress by inhibiting ER Ca(2+)-ATPase, also increased both hepatic MT levels and expression of MT-I and -II mRNA. The level of expression of Bip/GRP78 mRNA induced by Tun administration in MT-null mice was greater than that in wild-type mice. Taken together, these findings suggest that inhibitors of ER are potent inducers of MT.

Thin foil specimens of Cu and Au were irradiated with fission neutrons at 285–295 K to neutron fluences of 7 × 10 21 n m −2 (>0.1 MeV), using the Kyoto University Reactor. The structure of cascades and subcascades was examined by fitting the experimentally observed distribution of vacancy-type defect clusters to the calculated primary recoil energy spectrum, and was compared directly with that for fusion neutron irradiation. In Cu, 70% of cascades consist of only one defect cluster and 2% of more than four clusters. This is in contrast to larger cascades produced by 14 MeV neutrons that contain more than 10 clusters and extend 60 nm in diameter. The subcascade energy was 18 and 15 keV for Cu and Au, respectively. These values are about 30–60% higher than those obtained for fusion neutron irradiation.

An inbred turnip ( Brassica rapa syn. campestris) line, N-WMR-3, which carries the trait of clubroot resistance (CR) from a European turnip, Milan White, was crossed with a clubroot-susceptible doubled haploid line, A9709. A segregating F(3) population was obtained by single-seed descent of F(2) plants and used for a genetic analysis. Segregation of CR in the F(3) population suggested that CR is controlled by a major gene. Two RAPD markers, OPC11-1 and OPC11-2, were obtained as candidates of linkage markers by bulked segregant analysis. These were converted to sequence-tagged site markers, by cloning and sequencing of the polymorphic bands, and named OPC11-1S and OPC11-2S, respectively. The specific primer pairs for OPC11-1S amplified a clear dominant band, while the primer pairs for OPC11-2S resulted in co-dominant bands. Frequency distributions and statistical analyses indicate the presence of a major dominant CR gene linked to these two markers. The present marker for CR was independent of the previously found CR loci, Crr1 and Crr2. Genotypic distribution and statistical analyses did not show any evidence of CR alleles on Crr1 and Crr2 loci in N-WMR-3. The present study clearly demonstrates that B. rapa has at least three CR loci. Therefore, the new CR locus was named Crr3. The present locus may be useful in breeding CR Chinese cabbage cultivars to overcome the decay of present CR cultivars.

Wool keratin and silk fibroin are excellent biopolymers with outstanding properties that make them extremely valuable for biomedical and biotechnological applications. As proteins, fibroin and wool can be chemically modified at side chain groups of constituent amino acids, thus improving their properties according to the desired function. Among the chemical modifications techniques, graft copolymerization of vinyl monomers onto silk fibres has been considered a powerful method to substantially improve some intrinsic fibre properties. Grafted fibres represent an interesting model for studying the possible structural changes induced by grafting and the interactions between the fibre matrix and the grafted polymer chains. On the other hand, the reaction of selected chemical agents with fibres is a particularly attractive system that can be used to obtain effective and specific modifications of the fibrous substrate. Significant changes in the physical and chemical properties of the fibres can be obtained, avoiding some of the drawbacks that arise from graft-copolymerization of vinyl monomers and from the loading of the fibre with large amounts of polymer, which is often needed to obtain the desired effects. In the present study, IR and Raman spectroscopy has been used to comparatively analyse the reactivity of vinyl monomers (styrene, methacrylamide) and anhydrides (succinic and glutaric anhydrides) towards Bombyx mori and Antheraea pernyi silk fibroin, and wool. Several spectroscopic ratios were identified as markers of the extent of grafting/chemical modification, due to their rough proportionality to the fibre weight gain. Vibrational techniques have been widely recognized as valid tools for studying the secondary structure of polypeptides and proteins. The positions and relative intensities of the Amide I, II and III modes were evaluated to probe the possible occurrence of conformational rearrangements upon reaction. In wool, the Raman SS stretching region was investigated to gain insight into the conformational changes of the CC-S-S-CC system. In silk fibroin the I850/I830 Raman intensity ratio between the two Tyr bands at 850-830 cm-1 gave information on Tyr environment. Vibrational spectroscopy proved suitable for evaluating the reactivity of the analysed fibres towards the different agents; the observed differences can be explained in terms of the different composition of the fibres and accessibility of the amino acids potentially involvable in the reactions.

Wool keratin and silk fibroin are excellent biopolymers with outstanding properties that make them extremely valuable in biomedicai field. Coatings are commonly applied to the surface of materials to improve their surface properties. The biocompatibility and non-immunogenicity of silk proteins should allow their application as coatings for biomedical implants, potentially as anticoagulants, and either promoters or inhibitors of cell adhesion. Incorporation of sulphate and sulphonate groups confers anticoagulant and anti-thrombogenic properties to polymers. In view of widening the biomedicai utility of natural polymers as biomaterials, here we present a comparative vibrational study on wool, B. morì and A. pernyi silk fibroin fibres sulphated with chlorosulphonic acid in pyridine, which is known to enhance the yield of sulphation. Our aim is to prepare sulphated fibres by keeping the intrinsic fibre properties and texture unchanged, using short reaction times (i.e. 3h). The fibres were analyzed by Attenuated Total Reflectance, ATR/FT-IR and FT-Raman spectroscopy to comparatively elucidate the affinity for sulphate groups, the mechanism and the mode of linkage, the amino acid side-chains involved, and the possible conformational changes caused by sulphation. Among the analysed samples, the vibrational spectra of sulphated wool fibres showed the most pronounced changes, suggesting the highest affinity towards sulphation. New bands in the 1300-1200 and 1100-900 cm-1 ranges were assigned to the formation of alkyl and aryl sulphate salts, sulphonamides, sulphoamines and covalent aryl-alkyl sulphates. Vibrational spectra revealed the occurrence of a certain fibre degradation as well as rearrangements with consequent changes in secondary structure, conformation of disulphide bridges and tyrosine environment. The amino acid residues mainly involved in sulphation were identified as serine, threonine, tyrosine and tryptophan. Upon sulphation, the IR and Raman spectra of B. mori silk fibroin fibres showed analogous changes although less pronounced than for wool fibres. No significant changes were detected for A. pernyi silk fibroin fibres: only slight conformational rearrangements were observed. The reactivity towards sulphation was found to decrease along the series: wool > B. mori silk fibroin > A. pernyi silk fibroin, in agreement with the weight gain measurements which decreased along the same series. These results can be explained in relation to the different composition of the analysed fibres. Wool fibres were characterised by the highest content of the potentially reactive sites; evidently, these groups had also a good accessibility for the sulphating agent.

We examined the association between green tea consumption and mortality due to all causes, cancer, heart disease, cerebrovascular disease, respiratory disease, injuries, and other causes of death in a large-scale population-based cohort study in Japan.We studied 90,914 Japanese (aged between 40 and 69 years) recruited between 1990 and 1994. After 18.7 years of follow-up, 12,874 deaths were reported. The association between green tea consumption and risk of all causes and major causes of mortality was assessed using the Cox proportional hazards regression model with adjustment for potential confounders.Hazard ratios for all-cause mortality among men who consumed green tea compared with those who drank less than 1 cup/day were 0.96 (0.89-1.03) for 1-2 cups/day, 0.88 (0.82-0.95) for 3-4 cups/day, and 0.87 (0.81-0.94) for more than 5 cups/day (P for trend.001). Corresponding hazard ratios for women were 0.90 (0.81-1.00), 0.87 (0.79-0.96), and 0.83 (0.75-0.91; P for trend.001). Green tea was inversely associated with mortality from heart disease in both men and women and mortality from cerebrovascular disease and respiratory disease in men. No association was found between green tea and total cancer mortality.This prospective study suggests that the consumption of green tea may reduce the risk of all-cause mortality and the three leading causes of death in Japan.

1 Using the cannula inserting method, vasodilator responses to β-adrenoceptor agonists (isoprenaline, denopamine and procaterol) were investigated in isolated and perfused rat common carotid arteries. 2 Each β-adrenoceptor agonist induced a vasodilation in preparations preconstricted by phenylephrine in a dose-related manner. The potencies were in the order of isoprenaline > procaterol >> denopamine. 3 Denopamine-induced dilations were significantly inhibited by 1 nmol betaxolol (a selective β1-adrenoceptor antagonist), but it was not influenced by 1 nmol ICI 118,551 (a selective β2-adrenoceptor antagonist). On the other hand, procaterol-induced vasodilations were significantly inhibited by 1 nmol ICI 118,551 but not modified by 10 nmol betaxolol. 4 ACh-induced vasodilations disappeared after intraluminal saponin injection to remove endothelium, but procaterol- and denopamine-induced dilations were not modified by removal of the endothelium. 5 Pretreatment with L-NG-nitroarginine methyl ester (L-NAME) readily inhibited ACh-induced vasodilations. However, neither procaterol- or denopamine-induced vasodilation was modified by L-NAME treatment. 6 From these results, it is concluded that in the rat common carotid arteries (1) there are abundant β2- and a few β1-adrenoceptors, and (2) there is no participation of the endothelium-dependent mechanism in β-adrenoceptor mediated vasodilations.

Silk fabrics were treated with chlorosulphonic acid in pyridine for different times. The amount of sulfur bound to silk increased during the first 2 h of reaction and then reached a plateau. The amino acidic pattern of sulfated silk remained essentially unchanged for short reaction times (< or =2 h). Longer reaction times resulted in drastic changes in the concentration of Asp, Glu, and Tyr. Surface morphology and texture of silk fabrics changed upon sulfation. Warp and weft yarns became progressively thinner, and deposits of foreign material appeared on the fiber surface. Changes were more evident at longer reaction times (> or =2 h). Spectroscopic analyses performed by FT-IR and FT-Raman showed the appearance of new bands attributable to various vibrations of sulfated groups. The IR bands at 1049 and 1014 cm-1, due to organic sulfate salts, were particularly intense. Bands assigned to alkyl sulfates and sulfonamides appeared in the 1300-1180 cm-1 range. Organic covalent sulfates displayed a weak but distinct IR band at 1385 cm-1. Both IR and Raman spectra revealed that silk fibroin mainly bound sulfates through the hydroxyl groups of Ser and Tyr, while involvement of amines could not be proved. Changes observed in the amide I and II range indicated an increase of the degree of molecular disorder of sulfated silk. Accordingly, the I850/I830 intensity ratio between the two Tyr bands at 850-830 cm-1 increased from 1.41 to 1.52, indicating a more exposed state of Tyr residues in sulfated silk. TGA, DSC, and TG analyses showed that sulfated silk attained a higher thermal stability. A thermal transition attributable to sulfated silk fibroin fractions appeared at about 260 degrees C in the DSC thermograms.

There is considerable interest in exploiting natural polymers processing to create high-performing, environmentally friendly polymers for a range of biomedical applications. Silk fibroin is a natural polymer spun by silkworms and spiders, commonly used as a textile fibre. Recent investigations have proposed silk fibroin as a good basic component for new biomedical material development. In particular, silk fibres have been considered as starting material for the preparation of various kinds of medical devices, such as polymer-hydroxyapatite composites for bone regeneration, wire-ropes for the substitution of the anterior cruciate ligament, novel silk-based sutures and protective gauzes for the treatment of skin burns with improved blood compatibility. Silk films, which can be prepared by casting an aqueous silk fibroin solution, are highly attractive for their permeability to oxygen and water vapour. Likewise fibres, films exhibit the ability to support cell adhesion and growth, and their use as scaffolds for skin and bone regeneration has been proposed. Being a protein, fibroin is susceptible to biological degradation and can be chemically modified at side-chain groups thus improving its properties according to the function. Our studies on the degradation behaviour of silk fibres and films exposed to different proteolytic enzymes allow to elucidate the mechanism by which the material interacts with the biological environment, and to characterise the functional properties of the polymer. On the other hand, the possibility of modifying silk fibroin by using a non-hydrolitic enzyme (tyrosinase) and chemical agents (chlorosulphonic acid or metal cations with EDTA or tannic acid) to obtain functionalised biomaterials was studied. Tyrosinase allowed to obtain an intermediate able to graft chitosan onto Bombyx mori silk fibroin; chlorosulphonic acid was used to introduce covalently bound sulphate groups which confer to fibroin anticoagulant and antiviral activity. The metal binding (Ag+, Cu2+ and Co2+), which was enhanced by chemically modifying the fibres with chelating agents able to coordinate metal ions (EDTA or tannic acid), impart antimicrobial activity on fibroin. This review points out the contribution that Raman and IR spectroscopy can give to the knowledge of the structural modifications related to the obtainment of functionalised biomaterials such as the reaction mechanisms, the interactions between molecules and the intermediate which can form.

Bombyx mori silk fibers were dissolved in N-methyl morpholine N-oxide (MMNO), an organic cyclic amine oxide used for the solvent spinning of regenerated cellulosic fibers. The commercial MMNO monohydrate used in this study as a solvent for silk is a hygroscopic compound crystalline at room temperature, which becomes an active solvent after melting at 76 degrees C. The degree of hydration of MMNO was checked by DSC measurements. The solvation power of MMNO towards silk fibroin drastically decreased at a water content > or = 20-21% w/w. Dissolution of silk required both thermal and mechanical energy. The optimum temperature was 100 degrees C. At lower temperatures dissolution proceeded very slowly. At higher temperatures, rapid depolymerization of silk fibroin occurred. The value of the Flory-Huggins interaction parameter chi for the MMNO-H2O-silk fibroin system was -8.5, suggesting that dissolution is a thermodynamically favored process. The extent of degradation of silk fibroin was assessed by measuring the intrinsic viscosity and determining the amino acid composition of silk after regeneration with an aqueous methanol solution, which was effective in removing the solvent and coagulating silk. Regenerated silk fibroin membranes were characterized by infrared spectroscopy, differential scanning calorimetry and scanning electron microscopy. The prevailing molecular conformation of silk fibroin chains was the beta-sheet structure, as shown by the intense amide I-III bands at 1704, 1627, 1515, 1260, and 1230 cm(-1). The value of the I1260/I1230 intensity ratio (crystallinity index) was 0.68, comparable to that of the fibers. The DSC thermogram was characteristic of a silk fibroin material with unoriented beta-sheet crystalline structure, with an intense decomposition endotherm at 294 degrees C. The SEM examination of fractured surfaces showed the presence of a dense microstructure with a very fine texture formed by densely packed roundish particles of about 100-200 nm diameter.

Silk is a natural product mainly composed by two proteins: fibroin and sericin. Fibroin is the main component of silk fiber and sericin glues the fibroin filaments in the cocoon and in textile is removed by boiling in water (degumming process). Silk can be easily functionalized, and its structure and morphology modulated to match a wide range of working requirements. In recent years, the unique chemical, mechanical, and biological properties of silk have made this natural polymer a highly attractive candidate for the development of innovative biomedicai devices (i.e. scaffolds for tissue engineering). Recently Tamada has reported that sulfated silk proteins show anticoagulant activity like a sulfated natural polysaccharide such as heparin and Gotoh et al. have demonstrated that sulfated silk fìbroins have potential as antiviral material. Here we present an i.r. and Raman study on fibroin and sericin treated with chlorosulfonic acid in pyridine in order to elucidate the mode of linkage of sulfate groups and the amino acids involved as well as the possible conformational changes caused by sulfation. The trend of both IR and Raman spectra of sulfated silk fabrics showed that conformational changes occurred by effect of sulfation and revealed that fibroin covalently bound sulfate groups mainly through the hydroxyl groups of tyrosine and serine leading to the formation of sulfate salts. At higher sulfation rate the formation of organic covalent sulfates may be proved by the appearance of the IR band at 1385 cm-1. This result points out a possible cross-linking of fibroin chains and could explain the formation of an insoluble fraction during the sulfation reaction as reported by Tamada. The involvement of the amine groups of basic residues in the sulfation reaction is not easily detectable. Nevertheless, the increase in intensity of the Raman band at 1164 cm-1 may reasonably account for this. The same trend can be observed in the spectra of sericin. Due to the different amino acid composition and structural organization, sericin seems to react more than fibroin mainly through the hydroxyl groups of serine.

Influence of the liquid composition, concentration of the potassium acetate, substrate-liquid distance and liquid layer thickness on the diamond formation were surveyed under a constant current for deposition during 1 h. Optimum deposition conditions were found to be 0.1 mol % potassium acetate, 8 mm substrate-liquid distance and 10–20 mm liquid layer thickness. Diamond forming liquid composition was then examined under a constant substrate temperature. It ranged from 60 to 99.9 mol % ethylene glycol; end compositions showed a poor yield. A constant substrate temperature was maintained under a constant current for temperatures lower than 900 °C. However, an important current reduction was required during the deposition to keep the substrate temperature higher than 1000 °C.

In this study, A. pernyi silk fibroin (Ap-SF) films were incubated with Protease Type XXI from Streptomyces griseus, at 37°C, to investigate the degradation behaviour in an in vitro model system. The enzyme-resistant fractions of Ap-SF films and the soluble peptides formed by proteolytic degradation were collected at specified times, from 1 to 17 days, and analyzed by high performance liquid chromatography (HPLC), differential scanning calorimetry (DSC), FT-Raman and FT-IR spectroscopy. Proteolysis resulted in extensive weight loss and progressive fragmentation of films, especially at long degradation times. A range of soluble peptides was formed by proteolysis. By HP-size exclusion chromatography it was found that their average molecular weight changed with the time of incubation. The chemical analysis of the enzyme-resistant fraction of Ap-SF films at different times of degradation indicated that the proteolytic attack preferentially occurred in the less ordered Gly-rich sequences, and that the Ala-rich crystalline regions of biodegraded films were enriched. Accordingly, DSC and spectroscopic results showed an enhancement of the crystalline character of the biodegraded films. From the behaviour of the most important thermal transitions it was deduced that the -helix domains probably represent the most enzyme-resistant fraction. The in vitro approach used in the present study seems a valid tool for studying the rate and mechanism of degradation of Ap-SF films and of other biopolymers of potential biomedical utility.

Recently, there has been an increased incidence of diabetes mellitus in Japan, where the rate of stroke is high. We reviewed the risk factors of stroke with special reference to "Syndrome X." We reviewed a population-based cohort from 1989 through 1991 that consisted of 7,456 subjects over the age of 35 at Akita, a stroke-prevalent rural district in the northeastern part of Japan known to have the shortest longevity and the highest alcohol consumption in the country. Baseline data were obtained by a questionnaire, physical exams, and blood serum tests. Physical characteristics were similar to national norms, although the proportion of heavy (ex-)drinkers was higher (72.5% for male; 12.0% for female). The prevalence of diabetes mellitus, hypertension, and Syndrome X (defined as diabetes mellitus plus hypertension) was 3.0%, 47.0%, and 1.9%. Observed prevalence of Syndrome X was higher than the expected value. The tendency to disease-clustering was strong in young females. The risk factors of Syndrome X wer...

A rack-mounted prototype of a broadcast-and-select (B and S) photonic ATM switch is fabricated. This switch has an optical output buffer utilizing wavelength division multiplexed (WDM) signals. The WDM technology solves. The cell-collision problem in a broadcast-and-select network and leads to a simple network architecture and the broadcast/multicast function. The prototype can handle 10-Gb/s nonreturn-to-zero (NRZ) coded cells and 5-Gb/s Manchester-coded cells and has a switch size of four. In this prototype, the level and timing design are key issues. Cell-by-cell level fluctuation is overcome by minimizing the loss difference between the optical paths and adopting a differential receiver capable of auto-thresholding. The temperature control of delay lines was successful in maintaining the phase synchronization. Using these techniques, we are able to provide a WDM highway with a bit error rate of less than 10/sup -12/. Fundamental photonic ATM switching functions, such as optical buffering and fast wavelength-channel selection, are achieved. We show our experimental results and demonstrate the high performance and stable operation of a photonic ATM switch for use in high-speed optical switching systems as an interconnect switch for a modular ATM switch and an ATM cross-connect switch.

Silk sericin (SS) protein is a raw material emerging into biomedical applications due to its outstanding biological properties. Electrospinning, an electrostatic nanofiber-manufacturing technique, has gained interest due to its versatility and potential applications in diverse fields. Electrospun nanofibrous materials offer advantages such as high aspect ratios and specific surface areas, tunable porosity and the ability to manipulate nanofiber composition to attain desired properties. This chapter examines how electrospinning was employed to produce SS nanofibers with smaller diameters, a narrow diameter distribution, smooth surfaces and bead-free structures. The effects on the morphological appearance of SS fibers were examined, as were the structure and physical characteristics of the nanofibers.

The crystal structure of an endoperoxide of tetrabenzo[de,hi,op,st]pentacene (TBPA-O2) was determined by X-ray crystallography. The unusually long OO and CO bonds were rationalized by the characteristic molecular structure of TBPA-O2. The photochromic behavior between TBPA-O2 and TBPA was discussed based on the enthalpy difference between TBPA-O2 and TBPA + O2 and the thermodynamic parameters of the extrusion reaction of oxygen from TBPA-O2.