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Science China Chemistry 2008年第5期51卷 479-486页

作者： shiro SAKA Department of Socio-Environmental Energy Science Graduate School of Energy ScienceKyoto University

Microcrystalline cellulose (avicel) is treated in hot-compressed aprotic solvents, sulfolane and 1,4-dioxane, using a batch-type reaction system with a molten tin bath in a range from 290 to 390°C. The corresponding densities of the solvent are 0.25–1.26 g/cm3 and 0.21–1.03 g/cm3 for sulfolane and 1,4-dioxane, respectively. As a result, in both solvents, more than 90% of cellulose is found to be decomposed to the solvent-soluble portion in which levoglucosan is the main component with the highest yield of about 35% on original cellulose basis. The decomposition rate to levoglucosan is, however, faster in sulfolane than in 1,4-dioxane, while levoglucosan is more stable in 1,4-dioxane. In addition, its yield is found to be solvent-density dependent to be highest around 0.4–0.5 g/cm3 for both solvents. To elucidate these decomposition behaviors, the results obtained in this study with aprotic solvents are compared with protic solvents such as water and methanol in previous works.

关键词： cellulose aprotic solvent solvent density decomposition behavior

Pancreatic cancer early detection:Expanding higher-risk group with clinical and metabolomics parameters

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World Journal of Gastroenterology 2015年第6期21卷 1707-1717页

作者： shiro Urayama Division of Gastroenterology and Hepatology Department of Internal Medicine University of California Davis

Pancreatic ductal adenocarcinoma(PDAC)is the fourth and fifth leading cause of cancer death for each gender in developed *** lack of effective treatment and screening scheme available for the general population,the mortality rate is expected to increase over the next several decades in contrast to the other major malignancies such as lung,breast,prostate and colorectal *** ultrasound,with itshighest level of detection capacity of smaller pancreatic lesions,is the commonly employed and preferred clinical imaging-based PDAC detection *** molecular biomarkers have been investigated for characterization of the disease,but none are shown to be useful or validated for clinical utilization for early *** seen from studies of a small subset of familial or genetically high-risk PDAC groups,the higher yield and utility of imaging-based screening methods are demonstrated for these *** recent studies on the unique cancer metabolism including PDAC,demonstrate the potential for utility of the metabolites as the discriminant markers for this *** order to generate an early PDAC detection screening strategy available for a wider population,we propose to expand the population of higher risk PDAC group with combination clinical and metabolomics parameters.

关键词： Pancreatic cancer Endoscopic ultrasound Metabolomi

Role of Salix reinii patches in spatio-temporal patterns of cohabitants on a Japanese volcano

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Journal of Plant Ecology 2022年第1期15卷 71-84页

作者： Miyuki Matsuda shiro Tsuyuzaki Division of Integrated Environmental Science Graduate School of Environmental Earth ScienceHokkaido UniversitySapporo 060-0810Japan IDEA Consultants Inc. 3-15-1 KomazawaSetagaya WardTokyo 154-8585Japan

Shrub patches often support the colonizers particularly under stressful and/or disturbed *** intensities of stresses and disturbances on mountains are often related to an elevation gradient and are decreased by shrub patches(canopy and litter).We aim to clarify these relationships by using shrub patches at different elevations on a *** monitored all shoots in plots established inside and outside of patches of Salix reinii(Salicaceae)and their related environments,such as temperature,light,moisture and chemistry,at three elevations on Mount Koma(1131 m a.s.l.),northern Japan,from early spring in 2005 to summer in *** patch structures were evaluated by area,branch density and litter *** structures of shrub patches did not differ among the *** patches increased the diversity of rare species,by an overall increase in plant species *** moisture,nitrogen and phosphate contents in the patches were higher than outside of *** effects of shrub patches on the cohabitants were overall positive,although the effects were negative on seedling abundance,shoot survival and *** results suggest that the growth patterns of shrub patches determine the plant community structures and facilitate plant diversity.

关键词： elevational difference interspecific interaction litter accumulation microenvironment shrub patch

Electromechanically reconfigurable plasmonic photodetector with a distinct shift in resonant wavelength

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Microsystems & Nanoengineering 2023年第2期9卷 219-226页

作者： Masaaki Oshita shiro Saito Tetsuo Kan Graduate School of Informatics and Engineering The University of Electro-Communications1-5-1ChofugaokaChofu-cityTokyo 182-8585Japan IMRA JAPAN CO. LTD2-36Hachiken-choKariyaAichi 448-8650Japan

Plasmonic photodetectors have received increasing attention because their detection properties can be designed by tailoring their metal structures on surfaces without using any additional *** of the plasmonic resonant state in a photodetector is relevant for various applications,including investigating in situ adaptive detection property changes,depending on the situation,and performing single-pixel spectroscopy in geometrically limited ***,the spectral responsivity change with conventional reconfiguration methods is relatively ***,we propose a plasmonic photodetector that reconfigures its spectral responsivity with electromechanical deformation instead of bias *** photodetector consists of a gold plasmonic grating formed on an n-type silicon cantilever,and the spectral responsivity is reconfigured by electromechanically scanning at an incident angle to the grating on the *** photodetector exhibits peak shifts in spectral responsivity in a wavelength range from 1250 to 1310 nm after electromechanical ***,for potential future applications,we demonstrate near-infrared spectroscopy using the *** photodetector has the potential to be adopted as a near-infrared spectrometer in industrial silicon imaging systems because its structure enables subbandgap photodetection on silicon by a Schottky junction.

关键词： tuning reconfigurable resonant

Immune checkpoint and inflammation as therapeutic targets in pancreatic carcinoma

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World Journal of Gastroenterology 2016年第33期22卷 7440-7452页

作者： shiro Kimbara Shunsuke Kondo Department of Experimental Therapeutics National Cancer Center Hospital

Pancreatic adenocarcinoma(PAC) is one of the most deadly malignant neoplasms,and the efficacy of conventional cytotoxic chemotherapy is far from satisfactory. Recent research studies have revealed that immunosuppression and inflammation are associated with oncogenesis,as well as tumor development,invasion,and metastasis in PAC. Thus,immunosuppressionrelated signaling,especially that involving immune checkpoint and inflammation,has emerged as novel treatment targets for PAC. However,PAC is an immuneresistant tumor,and it is still unclear whether immune checkpoint or anti-inflammation therapies would be an ideal strategy. In this article,we will review immune checkpoint and inflammation as potential targets,as well as clinical trials and the prospects for immunotherapy in PAC.

关键词： Immune checkpoint Therapeutic anticancer target Inflammation Randomized clinical trial Pancreatic adenocarcinoma

Changes in microbial community composition in the leaf litter of successional communities after volcanic eruptions of Mount Usu, northern Japan

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Journal of Mountain Science 2016年第9期13卷 1652-1662页

作者： Michiru OTAKI Fumiko TAKEUCHI shiro TSUYUZAKI Graduate School of Environmental Science Hokkaido University

Changes in the fungal and bacterial biomass and community structure in litter after the volcanic eruptions of Mount Usu, northern Japan were investigated using a chronosequence approach, which is widely used for analyzing vegetation succession. The vegetation changed from bare ground （10 years after the eruptions） with little plant cover and poor soil to monotonic grassland dominated by Polygonum sachalinense with undeveloped soil （33 years） and then to deciduous broad-leaved forest dominated by Populus maximowiczii with diverse species composition and well-developed soil （100 years）. At three chronosequential sites, we evaluated the compositions of phospholipid fatty acids （PLFAs）, carbon （C） and nitrogen （N） contents and the isotope ratios of C （δ13C） and N （δ15N） in the litter of two dominant species, Polygonum sachalinense and Populus maximowiezii. The C/N ratio, δ13C and δ15N in the litter of these two species were higher in the forest than that in the bare ground and grassland. The PLFAs gradually increased from the bare ground to the forest, showing that microbial biomass increased with the development of the soil and/or vegetation. The fungi-to-bacteria ratio of PLFA was constant at 5.3 ± 1.4 in all three sites, suggesting that fungi were predominant. A canonical correspondence analysis suggested that the PLFA comoosition was related to the successional ages and the developing soil properties （P 〈 0.05, ANOSIM）. The chrono- sequential analysis effectively detected the successional changes in both microbial and plant communities.

关键词： Volcanic succession Fungi-to-bacteriaratio Litter decomposition Microbial community Phospholipid fatty acids (PLFAs) Primary succession

Centrifuge modeling of buried continuous pipelines subjected to normal faulting

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 155-164页

作者： Majid Moradi Mahdi Rojhani Abbas Galandarzadeh shiro Takada School of Civil Engineering College of EngineeringUniversity of Tehran

Seismic ground faulting is the greatest hazard for continuous buried *** the years,researchers have attempted to understand pipeline behavior mostly via numerical modeling such as the finite element *** lack of well-documented field case histories of pipeline failure from seismic ground faulting and the cost and complicated facilities needed for full-scale experimental simulation mean that a centrifuge-based method to determine the behavior of pipelines subjected to faulting is best to verify numerical *** paper presents results from three centrifuge tests designed to investigate continuous buried steel pipeline behavior subjected to normal *** experimental setup and procedure are described and the recorded axial and bending strains induced in a pipeline are presented and compared to those obtained via analytical *** influence of factors such as faulting offset,burial depth and pipe diameter on the axial and bending strains of pipes and on ground soil failure and pipeline deformation patterns are also ***,the tensile rupture of a pipeline due to normal faulting is investigated.

关键词： centrifuge models buried pipeline normal faulting earthquake permanent ground deformation

Inhibitory Effects of 20α-Hydroxyprogesterone on Steroid Hydroxylation Reactions of Guinea Pig Adrenal Microsomes

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Science China Chemistry 1993年第4期36卷 411-419页

作者：黄德盈 shiro Kominami Shigeki Takemori Department of Chemistry South Central Institute for National Minorities Wuhan 430074 PRC Faculty of Integrated Arts and Sciences Hiroshima University

Using guinea pig andrenal microsomes, we studied the inhibitory effects of 20α-hydroxyprogesterone on steroid hydroxylation reactions catalyzed by cytochromes P-450. When 17α-hydroxyprogesterone was used as a substrate, 20α-hydroxyprogesterone functioned as a competitive inhibitor on the C_(17)—C_(20) bond cleavage reaction of P-450_(17α lyase). The inhibition constant, K_i was 1.37 μmol/L. 20α-hydroxyprogesterone also competitively inhibited the convertion of 17α-bydroxyprogesterone to 11-deoxycortisol by the action of P-450_(c21). The value of K_i was 1.73μmol/L. When progesterone was used as a substrate, 20α-hydroxyprogesterone inhibited neither the 21-hydroxylation of P-450_(c21). the C_(17)—C_(20) bond cleavage, nor 17α-hydroxylation of P-450_(17α lyase). Based on the seresults, we can deduce that the production of androstenedione from progesterone by the action of P-450_(17α lyase) proceeds through a successive monooxygenase reaction.

关键词： cytochrome P-450_(c21) cytochrome P-450_(17α lyase ) 20α-hydroxyprogesterone adrenal microsome steroidogenesis.

Characteristic of organic aerosol in a remote area of Okinawa Island

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Journal of Environmental Sciences 2009年第10期21卷 1371-1377页

作者： LUN Xiaoxiu TAKAMI Akinori MIYOSHI Takao HATAKEYAMA shiro Beijing Forestry University Beijing 100083 China National Institute for Environmental Studies Tsukuba 305-8506 Japan Tokyo University of Agriculture and Technology Tokyo 183-8538 Japan

A continuous investigation of aerosol pollutants in Cape Hedo, Japan was conducted from October 2005 to August 2006 by Aerodyne aerosol mass spectrometer （AMS）. This article focused on the analysis of long-range transport of organic aerosol from continental origin to the remote island. Based on the transport distance and air mass origin, four main air mass origins were considered, including North China, South China, Japan and Korea. Although the mass concentration and air mass origin were quite different during study period, the mass spectrum and size distribution of organic matter and oxidized organics were similar, which showed uni-modal distribution with modal diameter of around 500 nm. The loss rate of organics was （5.15 ± 0.55） × 10^-6 s^-1 obtained by plotting the concentration against the transport time. Conversion rate of SO2 to sulfate and oxidation rate of organics were （1.07 ± 0.15） × 10^-5 and （1.09 ± 0.52） × 10^-6 s^-1, respectively.

关键词： long-range transport Okinawa organics loss rate