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沿海声层析数据在印尼巴厘海峡的同化研究

海洋学报 2024年第8期46卷 121-130页

作者：于丰源许世杰谢心怡高怡心李光明 arita Kaneko Fadli Syamsudin 黄豪彩浙江大学海洋学院浙江舟山316021 国防科技创新研究院北京100071 日本广岛大学工程研究生院广岛739–8527 印度尼西亚技术评估与应用局雅加达10340

沿海声层析(Coastal Acoustic Tomography,简称CAT)是利用高频声信号实现近海大范围流场观测的有效手段,但其直接观测范围仍然有限。海洋数值模式提供了一种存在仿真误差的大范围海洋背景场,将CAT观测结果与海洋背景结果同化,可以提高... 详细信息

沿海声层析(Coastal Acoustic Tomography,简称CAT)是利用高频声信号实现近海大范围流场观测的有效手段,但其直接观测范围仍然有限。海洋数值模式提供了一种存在仿真误差的大范围海洋背景场,将CAT观测结果与海洋背景结果同化,可以提高流场结果的分辨率和准确度。本文提出一种利用流函数拟合海洋模式流场结果并使用集合卡尔曼滤波算法同化CAT数据的方法,获得更大范围的海洋水平二维流场结果。同化研究以非结构化网格有限体积海洋数值模式(Finite-Volume Community Ocean Model,简称FVCOM)作为背景场,以2016年6月1日至3日在印度尼西亚巴厘海峡(Bali Strait)进行的4站CAT实验作为观测数据。经过背景场流函数拟合和CAT数据同化,获得巴厘海峡二维流场。同化结果分别与同期观测结果和潮位数据对比,发现流函数拟合同化后的流场能更准确地描述巴厘海峡涨落潮和流量情况,通过引入CAT数据与流场的函数关系,可以有效地降低海洋模式的误差和原观测数据的稀疏性。

关键词：沿海声层析数据同化集合卡尔曼滤波流函数有限体积海洋模式

Examination of inverse Hall-Petch relation in nanostructured aluminum alloys by ultra-severe plastic deformation

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Journal of Materials Science & Technology 2021年第32期91卷 78-89页

作者： Abbas Mohammadi Nariman A.Enikeev Maxim YuMurashkin Makoto arita Kaveh Edalati WPI International Institute for Carbon-Neutral Energy Research(WPI-I2CNER)Kyushu UniversityFukuoka 819-0395Japan Institute of Physics of Advanced Materials Ufa State Aviation Technical UniversityUfa 450008Russia Department of Materials Science and Engineering Faculty of EngineeringKyushu UniversityFukuoka 819-0395Japan International Joint Laboratory for Light Alloys(MOE) College of Materials Science and EngineeringChongqing UniversityChongqing400045China

To have an insight into the occurrence of inverse Hall-Petch relationship in ultrafine-grained(UFG) aluminum alloys produced by severe plastic deformation(SPD),ultra-SPD(*** several ten thousand shear strains via high-pressure torsion,HPT) followed by aging is applied to an Al-La-Ce *** nanograin sizes of 40 and 80 nm are successfully achieved together with strain-induced Lomer-Cottrell dislocation lock formation and aging-induced semi-coherent Al_(11)(La,Ce)_3 *** of hardening mechanisms in this alloy compared to SPD-processed pure aluminum with micrometer grain sizes,SPD-processed Al-based alloys with submicrometer grain sizes and ultra-SPD-processed Al-Ca alloy with nanograin sizes reveals the presence of two breaks in the Hall-Petch ***,a positive upbreak appears when the grain sizes decrease from micrometer to submicrometer which is due to extra hardening by solute-dislocation ***,a negative down-break and softening occur by decreasing the grain sizes from submicrometer to nanometer which is caused by weakening the dislocation hardening mechanism with minor contribution of the inverse Hall-Petch *** analyses confirm that nanograin formation is not necessarily a solution for extra hardening of Al-based alloys and other accompanying strategies such as grain-boundary segregation and precipitation are required to overcome such a down-break and softening.

关键词： Aluminum-lanthanum-cerium alloys Nanostructured alloys Reverse Hall-Petch relationship Precipitation hardening Dislocation hardening

Management of neuroendocrine liver metastasis:Searching for new prognostic factor and appraising repeat hepatectomy

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Hepatobiliary Surgery and Nutrition 2021年第3期10卷 410-412页

作者： Junichi arita Sho Kiritani Kiyoshi Hasegawa Hepato-Biliary and Pancreatic Surgery Division Department of SurgeryGraduate School of MedicineUniversity of TokyoTokyoJapan

Gastro-enteric and pancreatic neuroendocrine neoplasm(NEN)is categorized as a borderline malignant tumor and was historically called carcinoid,meaning *** tumors usually grow slower than most carcinoma tumors originat... 详细信息

关键词： organs metastasis liver neoplasm

Hydriding properties of uranium alloys for purposes of searching for new hydrogen storage materials

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Nuclear Science and Techniques 2015年第1期26卷 121-126页

作者： Michio Yamawaki Takuya Yamamoto Yuji arita Fumihiro Nakamori Kazuhito Ohsawa Kenji Konashi Research Institute of Nuclear Engineering University of Fukui1-2-4 Kanawa-cho Tsuruga Fukui 914-0055 Japan Research Institute for Applied Mechanics Kyushu University6-1 Kasuga-koen Kasuga Fukuoka 816-8580 Japan Institute for Materials Research Tohoku University 2145-2 Narita-choOarai Higashi-Ibaragi-gun Ibaragi 311-1313 Japan

Hydriding properties of uranium alloys have been studied to search for new hydrogen storage materials to be applied to hydrogen energy systems. Application of uranium-base hydrogen storage materials can be expected to alleviate the risk, as well as to reduce the cost incurred by globally-stored large amounts of depleted uranium left after uranium enrichment. Various uranium alloys have been examined in terms of hydrogen absorptiondesorption properties, among which UNi Al intermetallic compound showed promising characteristics, such as lower absorption-desorption temperatures and better anti-powdering strength. First principle calculation has been carried out on UNi Al hydride to predict the change of crystal structure and the lattice constant with increasing hydrogen content, which showed this calculation to be promising in predicting candidates for good hydrogen absorbers.

关键词：氢化性能储氢材料铀合金第一原理计算金属间化合物能源系统解吸温度晶格常数

Lysophosphatidic acid induced nuclear translocation of nuclear factor-κB in Panc-1 cells by mobilizing cytosolic free calcium

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World Journal of Gastroenterology 2008年第28期14卷 4473-4479页

作者： Yoshiyuki arita Tetsuhide Ito Takamasa Oono Ken Kawabe Terumasa Hisano Ryoichi Takayanagi Department of Medicine and Bioregulatory Science Graduate School of Medical SciencesKyushu UniversityFukuoka 812-8582Japan

AIM: To clarify whether Lysophosphatidic acid (LPA) activates the nuclear translocation of nuclear factor-κB (NF-κB) in pancreatic cancer. METHODS: Panc-1, a human pancreatic cancer cell line, was used throughout the study. The expression of LPA receptors was confirmed by reverse-transcript polymerase chain reaction (RT-PCR). Cytosolic free calcium was measured by fluorescent calcium indicator fura-2, and the localization of NF-κB was visualized by immunofluorescent method with or without various agents, which effect cell signaling. RESULTS: Panc-1 expressed LPA receptors, LPA1, LPA2 and LPA3. LPA caused the elevation of cytosolic free calcium dose-dependently. LPA also caused the nuclear translocation of NF-κB. Cytosolic free calcium was attenuated by pertussis toxin (PTX) and U73122, an inhibitor of phospholipase C. The translocation of NF-κB was similarly attenuated by PTX and U73122, but phorbol ester, an activator of protein kinase C, alone did not translocate NF-κB. Furthermore, the translocation of NF-κB was completely blocked by Ca2+ chelator BAPTA-AM. Thapsigargin, an endoplasmic- reticulum Ca2+-ATPase pump inhibitor, also promoted the translocation of NF-κB. Staurosporine, a proteinkinase C inhibitor, attenuated translocation of NF-κB induced by LPA. CONCLUSION: These findings suggest that protein kinase C is activated endogenously in Panc-1, and protein kinase C is essential for activating NF-κB with cytosolic calcium and that LPA induces the nuclear translocation of NF-κB in Panc-1 by mobilizing cytosolic free calcium.

关键词： Lysophosphatidic acid Nuclear translocation Nuclear factor-κB Cytosolic free calcium Panc-1

Chemoradiotherapy with twice-weekly administration of low-dose gemcitabine for locally advanced pancreatic cancer

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World Journal of Gastroenterology 2008年第34期14卷 5311-5315页

作者： Hisato Igarashi Tetsuhide Ito Ken Kawabe Terumasa Hisano Yoshiyuki arita Toyoma Kaku Ryoichi Takayanagi Department of Medicine and Bioregulatory Science Graduate School of Medical ScienceKyushu University

AIM:To evaluate the chemoradiotherapy for locally advanced pancreatic cancer utilizing low dose gemcitabine as a radiation sensitizer administered twice weekly. METHODS: We performed a retrospective analysis of chemoradiotherapy utilizing gemcitabine administered twice weekly at a dose of 40 mg/m2. After that, maintenance systemic chemotherapy with gemcitabine, at a dose of 1000 mg/m2, was administered weekly for 3 wk with 1-wk rest until disease progression or unacceptable toxicity developed. RESULTS: Eighteen patients with locally advanced unresectable pancreatic cancer were enrolled. Three of those patients could not continue with the therapy; one patient had interstitial pneumonia during radiation therapy and two other patients showed liver metastasis or peritoneal metastasis during an early stage of the therapy. The median survival was 15.0 mo and the overall 1-year survival rate was 60%, while the median progression-free survival was 8.0 mo. The subgroup which showed the reduction of tumor development, more than 50% showed a tendency for a better prognosis; however, other parameters including age, gender and performance status did not correlate with survival. The median survival of the groups that died of liver metastasis and peritoneal metastasis were 13.0 mo and 27.7 mo, ***: Chemoradiotherapy with low-dose gemcitabine administered twice weekly could be effective to patients with locally advanced pancreatic cancer; however, patients developing liver metastases had a worse prognosis. Another chemoradiotherapy strategy might be needed for those patients, such as administrating one or two cycles of chemotherapy initially, followed by chemoradiotherapy for the cases with no distant metastases.

关键词： Advanced pancreatic cancer Chemoradio-therapy Gemcitabine Radiosensitizer Tumor marker

Production of CH4in a Low-Pressure CO2/H2Discharge with Magnetic Field

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Journal of Materials Science and Chemical Engineering 2015年第12期3卷 69-77页

作者： Keisuke arita Satoru Iizuka Department of Electrical Engineering Graduate School of Engineering Tohoku University Sendai Japan

Production of CH4 has been established using a low-pressure square-pulse cross-field CO2/H2 discharge with magnetic field. The conversion rate from CO2 to CH4 was investigated by changing the discharge parameters such as applied power and discharge distance, together with magnetic field strength. Carbon dioxide was reduced by hydrogen. The discharge took place across the magnetic field inside a glass tube. Decomposition of CO2 and CH4 selectivity are found to be dependent on power density. Energy efficiency for methane production is increased in a narrow discharge. Preferable improvements of CO2 decomposition, CH4 selectivity, and energy efficiency were established.

关键词： Carbon Dioxide Methane Pulse Discharge Magnetic Field

Helicobacter pylori infection in subjects negative for high titer serum antibody

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World Journal of Gastroenterology 2018年第13期24卷 1419-1428页

作者： Osamu Toyoshima Toshihiro Nishizawa Masahide arita Yosuke Kataoka Kosuke Sakitani Shuntaro Yoshida Hiroharu Yamashita Keisuke Hata Hidenobu Watanabe Hidekazu Suzuki Department of Gastroenterology Toyoshima Endoscopy Clinic Department of Pathology Pathology and Cytology Laboratory Japan Medical Education Center Keio University School of Medicine

AIM To investigate the clinicopathological features of the patients testing negative for high titer serum antiHelicobacter pylori(H. pylori) *** The antibody titers were measured using antigens derived from Japanese individuals. ^(13)C-urea breath test-positive individuals were defined as having H. pylori infection. We investigated the demographic characteristics, laboratory data, endoscopic findings including Kyoto classification of gastritis, and histology in negative-high titer patients without H. pylori eradication therapy. Kyoto classification consisted of scores for gastric atrophy, intestinal metaplasia, enlarged folds, nodularity, and *** Of the 136 subjects enrolled, 23(17%) had H. pylori infection. Kyoto classification had an excellent area under the receiver operating characteristics curve(0.886, 95% confidence interval: 0.803-0.968, P = 3.7 × 10^(-20)) for predicting H. pylori infection with a cutoff value of 2. Further, Kyoto classification, H. pylori density, and neutrophil activity had high accuracies(89.7%, 96.3%, and 94.1%, respectively). Kyoto classification was independent of the demographic and laboratory parameters in multivariate *** Endoscopic Kyoto classification of gastritis is a useful predictor of H. pylori infection in negative-high titer antibody patients.

关键词： Kyoto classification Gastritis Helicobacter pylori Antibody Endoscopy

Diameter Measurements of the Upper Parts of Trees Using an Ultra-Telephoto Digital Photography System

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Open Journal of Forestry 2014年第4期4卷 316-326页

作者： Akira Shimizu Shigeki Yamada Yuichiro arita Forestry and Forest Products Research Institute Tsukuba Japan Kyushu Research Centre Forestry and Forest Products Research Institute Kumamoto Japan Ogunimachi Forestry Cooperative Oguni-Machi Japan

We develop a new technique to measure the exact upper diameters of trees that is comparatively simple and inexpensive. We can measure the diameters of entire tree trunks efficiently and with high precision. The system uses a digital camera with a ~15 - 30× telephoto lens to take a photograph that can be used for measuring the diameter of the upper part of a comparatively slender tree trunk. Since this method requires a measuring distance and the height of the target point in the image, a range finder capable of measuring angles was combined with the main digiscoping system. A range finder sensor uses a laser and makes a 360 degree angle of observation possible. The diameter of a target position of the objective tree can be obtained by measuring the digital image using image editing software and calculations from spreadsheet software. We focus on the Japanese cedar species in the southwestern part of Japan. Photographic measurements were obtained prior to thinning. The estimates that we obtained largely agree with the true measurements of all trees. With regard to the estimated accuracy of all measured trees, the maximum error ratio was 7.0% (1.45 cm), with a ~2% - 4% error for most of the estimated results. Although the absolute value of the estimation error was 1.87 cm (5.3%) at the maximum (9.87 m in height and 35.5 cm in diameter), an estimation accuracy of <1 cm was reproduced in almost all measurements except for the extreme hypertrophy portion by butt swelling.

关键词： Digital Camera Image Editing Software Magnifications Spotting Scope Taper Curve Upper Diameter