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Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,Mexico

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Journal of Mountain Science 2024年第6期21卷 1954-1977页

作者： Víctor SOTO Carlos M.WELSH R. kenji yoshikawa Hugo DELGADO GRANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Environmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last Glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction Mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

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Glacial reconstruction and periglacial dynamics at the end of Late Pleistocene on the surface of Cofre de Perote volcano,México:a climatological retrospective

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Journal of Mountain Science 2023年第9期20卷 2453-2467页

作者： Victor SOTO Hugo DELGADO-GRANADOS Carlos M.WELSH kenji yoshikawa Centro de Ciencias de la Tierra Universidad VeracruzanaXalapaVeracruz 91090México Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Water and Environmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA

Despite being within the intertropical region of the planet,the Mexican territory still has glacier-covered *** recent decades,important advances have been made in studies on glaciology and periglacial environment in Mexico both for current and past ***,in spite of Cofre de Perote volcano(4200 m a.s.l.)being a strategically located mountain,it has not yet been studied in regards to the glacial and periglacial processes;in fact,those dynamics have modified the mountain massifs in the *** complement the series of studies on glacial history in the high mountain environment of México,this study reconstructs the glacial cover and the periglacial environment of the volcano surface during the final stage of the Late Pleistocene based on climatic retrospective and through the identification of geomorphological *** findings indicate the existence of a large glacier(ice cap)that covered the northern,western,and southern slopes of the mountain;while in the eastern sector there were two small glaciers,one being of cirque type,and the other of valley *** current temperature conditions prevent the occurrence of permanent ice bodies;at the same time,it was found that the periglacial blockfields of the slopes is a legacy of the climatic conditions that prevailed at the end of Late Pleistocene.

关键词： Cofre de Perote Glacial cover Periglacial environment Climatic retrospective Palaeoclimatic modelling

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The Use of Geophysical Methods to Discriminate between Brine Layers and Freshwater Taliks in Permafrost Regions

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冰川冻土 2004年第S1期26卷 301-309页

作者： kenji yoshikawa Vladimir Romanovsky Nataria Duxbury Jerry Brown Alexandre Tsapin Water and Environmental Research Center Institute of Northern Engineering University of Alaska Fairbanks PO Box 755860 Fairbanks AK 99775-5860 USA Geophysical Institute University of Alaska Fairbanks 903 Koyukuk Drive P.O. Box 757320 Fairbanks AK 99775-7320 USA Jet Propulsion Laboratory 4800 Oak Grove Drive MS 183-301 Pasadena CA 91109 USA International Permafrost Association P.O. Box 7 Woods Hole MA 02543 USA

Direct current resistivity and ground penetrating radar surveys were employed to obtain the value of the resistivity and dielectric constant in the brine near the Barrow, Alaska. The geophysical surveys were undertaken together with the permafrost drilling program for the measuring of the ground temperature regime and for the core sampling. The sampled cores were measured for their physical and chemical properties in the laboratory under different temperature conditions ((-60) to (20) ℃). Laboratory results support field observations and led to the development of a technique for distinguishing freshwater taliks and brine layers in permafrost. These methods were also employed in freshwater taliks near Council, Alaska. The electrical resistivity is a powerful and sensitive parameter for brine detection. However, the resistivity is a less sensitive indicator of the soil type or water content under highly saline conditions. High frequency dielectric constant is an ideal second parameter for the indication of the soil type, liquid water content and other physical properties. The imaginary part of the dielectric constant and resistivity have a significant dependence upon salinity, i.e. upon freezing temperature. The ground temperature regime and the freezing point of the brine layer are important parameters for studying the electric properties of permafrost terrain.

关键词： geophysical method resistivity and dielectric constant talik Barrow,Alaska

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Historical Variability of the Icing（aufeis） in the Brooks Range,Alaska and Kunlun Mountain,China

Historical Variability of the Icing（aufeis） in the Brooks ...

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Asian Conference on Permafrost

作者： kenji yoshikawa ZHAO Lin Baisheng YE Water and Environmental Research Center Institute of Northern EngineeringUniversity of Alaska Fai irbanks Cold and Arid Regions Environmental and Engineering Research Institute CAS

Different remote sensing sensors were employed to obtain the characteristics of icing（aufeis） in the Brooks Range,Alaska and the Kunlun Mountains,*** truth results support remote sensing observations and led to the development of techniques to determine ice formation and spring water *** creates an important water storage,and an engineering hazard in the permafrost *** Synthetic Aperture Radar（SAR） is a powerful and sensitive sensor for ice detection,estimating volume of the ice,and freeze/thaw *** 27-30% of winter baseflow contributes to the icing at the Kuparuk Aufeis *** imagery from the Brooks Range indicates many of the high discharge springs are located less than 500 m *** limestone areas with glacial *** springs have survived at least through the last ***,the size of these icing deposits was similar to those found recently by identifying ASTER（Advanced Spaceborne Thermal Emission and Reflection Radiometer） shortwave infrared（SWIR） data.

关键词： Historical variability icing china

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应用等效纬度海拔模型进行地温及多年冻土制图(英)

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冰川冻土 2002年第5期24卷 526-531页

作者： kenji yoshikawa\+1,\ Larry D. Hinzman\+1,\ Prasad Gogineni\+2 (1.Water and Environmental Research Center, University of Alaska Fairbanks, USA 2.The University of Kansas, Radar Systems and Remote Sensing Laboratory, USA) Water and Environmental Research Center University of Alaska Fairbanks 美国 The University of Kansas Radar Systems and Remote Sensing Laboratory 美国

This research presents a method for permafrost mapping in discontinuous permafrost regions based on equivalent latitude/elevation concept in interior Alaska. In winter months, study site has a strong temperature inversion in air up to 700 m elevation. Air temperature data and the effects of slope, aspect and elevation were used to create an equivalent latitude/elevation model. This model was well correlated with mean annual surface temperature (0\^79). In this watershed, the thawing index (\%I\%\-t≈\{1 400\} ℃\5days) at the ground surface and snow depth do not vary greatly from south facing to north facing slopes. The primary controlled factor that determines the mean annual surface temperature was the winter surface temperature. The permafrost stability is effectively controlled by the freezing index. We determined 37\^5% of Caribou-Poker Creeks Research Watershed has unstable or thawing permafrost. At least 2\^1% of the permafrost in this watershed may have disappeared in the last 90 years due to climate warming. This method makes it possible to evaluate the permafrost stability in the present, past and future.

关键词：等效纬度-海拔模型地温多年冻土制图

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Discussion about Improvement of Stability of the Scan Timing by Placing Small ROI in Cerebral 3D-CTA

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Open Journal of Radiology 2015年第4期5卷 224-234页

作者： Yuichi Watanabe kenji Ino Kohki yoshikawa Department of Radiological Technology the University of Tokyo Hospital Tokyo Japan Graduate Division of Health Sciences Komazawa University Tokyo Japan

In three-dimensional computed tomography angiography (3D-CTA) in our facility, we usually scan the volume of the brain according to the bolus tracking method. Fluoroscopic slice is placed at the Willis’s ring and the timing of scan is determined subjectively by a radiological technologist after strong enhancement of the basal cerebral artery is confirmed. In these procedures, however, variation of scan timing is often problematic. Therefore, we design the surpassing method to place the small region-of-interest (ROI) at the basal cerebral arteries and to start CT scan automatically. In this protocol, the fluoroscopic slices of the distal internal carotid arteries are selected referring to the precontrast volume data, small ROIs are set in bilateral internal carotid arteries, and scan trigger of CT is started automatically at the threshold of 170 HU. The maximum 80 mL of iodine contrast agent 300 mgI/mL is injected intravenously at the rate of 4.0 mL/sec, and the volume of the arterial phase is scanned automatically. We measure ROIs at the internal carotid arteries based on the obtained volume data of arterial phase and estimate the optimal scan timings from the fluoroscopic CT images reformatted at the intervals of 0.1 sec. In 38 of 53 patients, placement of the small ROIs is succeeded and automatic or manual CT scan is performed. In the patients who succeed in placement of the small ROIs, optimal scan timing of the arterial phase is obtained, while in the patients who fail placement of the small ROIs, a large variation is observed in their scan timings. Their results suggest that more stable scanning of the arterial phase is available by means of small ROI placement and automatic scanning. The clinical significance is large because the stability and reproducibility of the examination provide a quantitative analysis and more accurate diagnosis.

关键词： Cerebral 3D-CTA Small ROI Bolus Tracking Volume Scan 320-Row CT

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Persistent CXCR4 expression after preoperative chemoradiotherapy predicts early recurrence and poor prognosis in esophageal cancer

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World Journal of Gastroenterology 2006年第47期12卷 7585-7590页

作者： kenji Koishi Reigetsu yoshikawa Tohru Tsujimura Tomoko Hashimoto-Tamaoki Syoudou Kojima Hidenori Yanagi Takehira Yamamura Yoshinori Fujiwara Second Department of Surgery Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Second Department of Surgery Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Institute for Advanced Medical Sciences Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Second Department of Pathology Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Institute for Advanced Medical Sciences Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Department of Genetics Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan

AIM: To study the effect of CXC chemokine receptor-4 (CXCR4) expression on disease progression and prognosis in esophageal cancer. METHODS: CXCR4 expression was evaluated in 37 patients with histologically confirmed esophageal squamous carcinomas (ESCC) undergoing preoperative chemoradiotherapy (CRT) by immunohistochemical staining. RESULTS: Eleven out of 37 ESCC patients showed a pathological complete response (CR) after CRT. CXCR4 protein expression was observed in cell cytoplasms of 13 tumors, and null expression was seen in 13 tumors. Distant recurrence was significantly more common in patients with positive CXCR4 expression (P = 0.0318). After a median follow-up time of 31.6 mo, 19 patients progressed (12 of 19 expressed positive CXCR4) and 11 died (10 of 11 expressed positive CXCR4). Overall survival was significantly correlated with lymph node metastasis (952.1 ± 53.8 d in negative group vs 475.1 ± 56.2 d in positive group, P = 0.023), distant metastasis (874.0 ± 60.4 d in negative group vs 434.9 ± 75.2 d in positive group, P = 0.014) and CRT (811.5 ± 51.2 d in responder group vs 459.6 ± 94.0 d in non-responder group, P = 0.00038) and further with an absence ofCXCR4 expression or no residual tumor (959.8 ± 51.0 d in null expression or no tumor group vs 412.0 ± 57.1 d in positive expression group, P = 0.0001). CONCLUSION: Persistent positive CXCR4 expression is implicated in tumor aggressiveness and poor prognosis in ESCC after CRT, and preoperative CRT may improve the prognosis of ESCC via CXCL12-CXCR4 signaling pathway.

关键词：食管癌癌细胞免疫组织化学 CRT

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Orbit insertion strategy of Hayabusa2’s rover with large release uncertainty around the asteroid Ryugu

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Astrodynamics 2020年第4期4卷 309-329页

作者： Yusuke Oki Kent yoshikawa Hiroshi Takeuchi Shota Kikuchi Hitosi Ikeda Daniel JScheeres Jay WMcMahon Junichiro Kawaguchi Yuto Takei Yuya Mimasu Naoko Ogawa Go Ono Fuyuto Terui Manabu Yamada Toru Kouyama Shingo K ameda Kazuya Yoshida kenji Nagaoka Tetsuo Yoshimitsu Takanao Saiki Yuichi Tsuda Japan A erospace Exploration Agency T'sukuba 305-8505Japan Japan Aerospace Exploration Agency Sagamihara 252-5210Japan University of Colorado BoulderCO 80309USA Planetary Exploration Research Center Chiba Institute of TechnologyNarashino 275-0016Japan National Institute of Aduanced Industrial Science and Technology Koto-ku 135-0064Japan Rikkyo University Toshima-ku 171-8501Japan Department of A erospace Engineering Tohoku UniversitySendai 980-8579Japan Kyushu Institute of Technology Kitakyusyu 804-8550Japan

This paper describes the orbit design of the deployable payload Rover 2 of MINERVA-II,installed on the Hayabusa2 *** Rover 2 did not have surface exploration capabilities,the operation team decided to experiment with a new strategy for its deployment to the *** rover was ejected at a high altitude and made a semi-hard landing on the surface of the asteroid Ryugu after several *** on the orbital analysis around Ryugu,the expected collision speed was tolerable for the rover to function *** the rover could not control its position,its motion was entirely governed by the initial ***,the largest challenge was to insert the rover into a stable orbit(despite its large release uncertainty),and avoid its escape from Ryugu due to an environment strongly perturbed by solar radiation pressure and gravitational *** study investigates the solution space of the orbit around Ryugu and evaluates the orbit’s robustness by utilizing Monte Carlo simulations to determine the orbit insertion *** analyzing the flight data of the rover operation,we verified that the rover orbited Ryugu for more than one period and established the possibility of a novel method for estimating the gravity of an asteroid.

关键词： solar radiation pressure augmented elliptic Hill three-body problem gravitational irregularity

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Cyclooxygenase-2 expression after preoperative chemoradiotherapy correlates with more frequent esophageal cancer recurrence

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World Journal of Gastroenterology 2007年第16期13卷 2283-2288页

作者： Reigetsu yoshikawa Yoshinori Fujiwara kenji Koishi Syoudou Kojima Tomohiro Matsumoto Hidenori Yanagi Takehira Yamamura Tomoko Hashimoto-Tamaoki Takashi Nishigami Tohru Tsujimura Second Department of Surgery Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Institute for Advanced Medical Sciences Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Second Department of Surgery Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Institute for Advanced Medical Sciences Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Department of Genetics Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan Second Department of Pathology Hyogo College of Medicine Nishinomiya Hyogo 663-8501 Japan

AIM: To investigate the relationship between cycloo- xygenase-2 (COX-2), and vascular endothelial growth factor (VEGF), and to determine the clinical significance of this relationship in esophageal cancer patients undergoing chemoradiotherapy (CRT). METHODS: Immunohistochemical staining was used to evaluate COX-2 and VEGF expression in 40 patients with histologically-confirmed esophageal squamous carcinoma (ESCC) who were undergoing preoperative CRT. RESULTS: Fourteen out of 40 ESCC patients showed a pathological complete response (CR) after CRT. COX-2 and VEGF protein expressions were observed in the cytoplasm of 17 and 13 tumors, respectively, with null expression in 9 and 13 tumors, respectively. COX-2 expression was strongly correlated with VEGF expression (P < 0.05). There were also significant associations between COX-2 expression, tumor recurrence, and lymph-node involvement (P = 0.0277 and P = 0.0095, respectively). COX-2 expression and VEGF expression had significant prognostic value for disease-free survival (log-rank test; P = 0.0073 and P = 0.0341, respectively), but not for overall survival, as assessed by univariate analysis. CONCLUSION: Our results suggest that COX-2 expression correlates with VEGF expression and might be a useful prognostic factor for more frequent tumor recurrence in ESCC patients undergoing neoadjuvant CRT. These findings support the use of anti-angiogenic COX-2 inhibitors in the treatment of ESCC.

关键词：食管癌复发手术前放化疗环加氧酶-2 基因表达

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Effect of Peptidase Inhibitors on Dynorphin A (1-17) or (1-13)-Induced Antinociception and Toxicity at Spinal Level

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Pharmacology & Pharmacy 2017年第2期8卷 33-51页

作者： Mitsumasa Matsuda Masanobu yoshikawa Takugi Kan Mariko Watanabe Junko Ajimi Shigeru Takahashi Masaaki Miura kenji Ito Hiroyuki Kobayashi Toshiyasu Suzuki Department of Anesthesiology School of Medicine Tokai University Isehara Japan Department of Clinical Pharmacology School of Medicine Tokai University Isehara Japan Department of Anesthesiology Hiratsuka City Hospital Hiratsuka Japan

Our group has earlier demonstrated that three enzymes sensitive to peptidase inhibitors (PIs), amastatin (A)-, captopril (C)-, and phosphoramidon (P), played an important role in inactivation of enkephalins at the spinal level. Dynorphin-converting enzyme (DCE) hydrolyzes dynorphin (Dyn) A (1-17) or Dyn A (1-13) mainly at the Arg6-Arg7 bond. Dynorphin A and its derived peptides interact with opioid and glutamate receptors at their N- and C-terminals, respectively. The purpose of the present study was to evaluate the antinociceptive potency and toxicity of intrathecal administered Dyn A (1-17), Dyn A (1-13), or Dyn A (1-6) under pretreatment with ACP and/or the DCE inhibitor p-hydroxymercuribenzoate (PHMB). The effect of these PIs on Dyn A (1-17)-induced inhibition of electrically-evoked contractions in mouse vas deferens was also investigated. The inhibitory potency of Dyn A (1-17) on electrically-evoked contractions in mouse vas deferens under pretreatment with ACP was higher than that with AC, AP, or CP. Pretreatment with ACP augmented Dyn A (1-17) or (1-13)-induced antinociception by approximately 50- or 30-fold with no sign of allodynia when administered intrathecally at low doses. Pretreatment with ACP and PHMB induced neuropathy. These findings showed that intrathecal administration of low-dose Dyn A (1-17) or DynA (1-13) increased antinociception under pretreatment with ACP, but without signs of allodynia in rat.

关键词： Dynorphin A Peptidase Dynorphin-Converting Enzyme Antinociception Allodynia

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