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Role of the floodplain lakes in the methylmercury distribution and exchanges with the Amazon River,Brazil

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Journal of Environmental Sciences 2018年第6期30卷 24-40页

作者： Poliana Dutra Maia Laurence Maurice Emmanuel Tessier David Amouroux Daniel Cossa Patricia Moreira-Turcq Henri Etcheber Universidade de Brasilia-Faculdade UnB Planaltina Area Universitaria n. 1-Vila Nossa Senhora de Fatima Planaltina 73300-000 Brasilia DF Brazil Geosciences Environnement Toulouse (GET) Observatoire Midi Pyrenees Universite de Toulouse CNRS IRD14 Avenue Edouard Belin F-32400 Toulouse France cnrs/Univ Pau & Pays Adour Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Materiaux UMR5254 F-64000 Pau Prance Universite Grenoble Alpes CP 40700 F-38058 Grenoble Cedex 9 France epoc umr 5805 Universite de Bordeaux I Av. des Facultes F-33405 Talence France

Seasonal variability of dissolved and particulate methylmercury（F-MeHg, P-MeHg） concentrations was studied in the waters of the Amazon River and its associated Curuai floodplain during hydrological year 2005–2006, to understand the MeHg exchanges between these aquatic systems. In the oxic white water lakes, with neutral pH, high F-MeHg and P-MeHg concentrations were measured during the rising water stage（0.70 ± 0.37 pmol/L, n = 26） and flood peak（14.19 ± 9.32 pmol/g, n = 7） respectively, when the Amazon River water discharge into the lakes was at its maximum. The lowest mean values were reported during the dry season（0.18 ± 0.07 pmol/L F-MeHg, n = 10 and 1.35 ± 1.24 pmol/g P-MeHg, n = 8）, when water and suspended sediments were outflowing from the lakes into the River. In these lakes,the MeHg concentrations were associated to the aluminium and organic carbon/nitrogen changes. In the black water lakes, with acidic pH and reducing conditions, elevated MeHg concentrations were recorded（0.58 ± 0.32 pmol/L F-MeHg, n = 16 and 19.82 ± 15.13 pmol/g PMeHg, n = 6）, and correlated with the organic carbon and manganese concentrations. Elevated values of MeHg partition coefficient（4.87 〈 Kd〈 5.08 log（L/kg） indicate that MeHg is mainly transported associated with the particulate phase. The P-MeHg enrichment detected in all lakes suggests autochthonous MeHg inputs from the sediments into the water column. The MeHg mass balance showed that the Curuai floodplain is not the source of P-MeHg for the Amazon River.

关键词： Methylmercury Water Sediment Amazon River Floodplain lakes

Natural regeneration of Pinus brutia Ten. in a recreational public forest in Zawita-Kurdistan region, Iraq

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Journal of Forestry Research 2019年第5期30卷 1849-1857页

作者： Hassan Muhamed Sami Youssef Ahmed Mustafa Hishyer Suliman Aree Abdulqader Hishyer Mohammed Richard Michalet Department of Forestry College of AgricultureUniversity of DuhokDuhokKurdistan RegionIraq AMAP(Botany and Modelling of Plant Architecture and Vegetation) University of Montpellier34398 Montpellier Cedex 5France Department of Ecotourism College of AgricultureUniversity of DuhokDuhokKurdistan RegionIraq Directorate of Forestry and Rangelands DuhokKurdistan RegionIraq umr cnrs 5805 epoc Universitede BordeauxAllee Geoffroy Saint-Hilaire CS 5002333615 Pessac CedexFrance

Zawita natural forest has recently has been subject to mass recreational activities during spring that have denuded large areas of the forest.It was thus essential to assess regeneration before designing optimizing strategies.To this end,we studied the overstory canopy and microhabitat conditions for recruitment of Pinus brutia Ten in 10 plots(20×25 m)on the southern aspects where the Zawita natural forest is still present.In total,1540 regenerating P.brutia were recorded,854 seedlings,597 saplings,and 89 trees.Seedlings and saplings were more frequent beyond the canopy than under the canopy of the parent trees.Regeneration requirements differed between seedlings and saplings.The probability of the occurrence of seedlings was negatively correlated with increasing litter depth and increasing soil compaction.The density of saplings only showed a positive significant correlation with increasing slope.The nearest neighbor index showed a trend toward a positive spatial association between understory shrubs with their neighboring seedlings at a mean distance of 1.6 m.Overall,the study highlighted the requirements for seedling regeneration as a relatively open canopy cover,a light understory litter layer,and noncompacted soils.These results are a step towards designing effective management and restoration programs.

关键词： Forest structure Litter depth Regeneration niche Spatial pattern Soil compaction

The hyperpycnite problem: comment

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Journal of Palaeogeography 2019年第3期8卷 314-320页

作者： A.J.(Tom) van Loon Heiko Hüneke Thierry Mulder Geocom Consulting Valle del Portet 17 03726 Benitachell Spain College of Earth Science and Engineering Shandong University of Science and Technology Qingdao 266590 Shandong China Institute of Geography and Geology Greifswald University Greifswald Germany umr cnrs epoc University of Bordeaux Allee Geoffroy St-Hilaire 33615 Pessac Cedex France

A recent review article("The hyperpycnite problem") by Shanmugam(Journal of Palaeogeography 7(3):197–238,2018) in this journal has some shortcomings, comes to scientifically incorrect conclusions, and calls for student education in a way that would significantly diminish the students’ changes for a geological career. Having studied--and still studying--hyperpycnites in the field, it seems only appropriate to inform the readers of this journal about our concerns regarding the review article mentioned above.Actually, the article by Shanmugam(Journal of Palaeogeography 7(3):197–238, 2018) is not a review paper but rather a comment, criticizing al researchers who have come to the conclusion, on the basis of both field research and theory,that hyperpycnal flows result in sediments(hyperpycnites) with characteristics that make it possible to distinguish them from deposits formed in another way. This is also the essence of Shanmugam’s comment: as he states himself, he is"an ardent critic of al genetic facies models".

关键词： review Shanmugam critic

2.45 GHz 0.8 mW voltage-controlled ring oscillator （VCRO） in 28 nm fully depleted silicon-on-insulator （FDSOI） technology

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Frontiers of Materials Science 2015年第2期9卷 156-162页

作者： Gilles JACQUEMOD Alexandre FONSECA Emeric de FOUCAULD Yves LEDUC Philippe LORENZINI epoc URE UNS 006 Universite Nice Sophia Antipolis Sophia Antipolis France CEA-LETI Grenoble France

MOS bulk transistor is reaching its limits： sub-threshold slope （SS）, drain induced barrier lowering （DIBL）, threshold voltage （VT） and VDD scaling slowing down, more power dissipation, less speed gain, less accuracy, variability and reliability issues. Fully depleted devices are mandatory to continue the technology roadmap. FDSOI technology relies on a thin layer of silicon that is over a buried oxide （BOx）. Called ultra thin body and buried oxide （UTBB） transistor, FDSOI transistors correspond to a simple evolution from conventional MOS bulk transistor. The capability to bias the back-gate allows us to implement calibration techniques without adding transistors in critical blocks. We have illustrated this technique on a very low power voltage-controlled oscillator （VCO） based on a ring oscillator （RO） designed in 28 nm FDSOI technology. Despite the fact that such VCO topology exhibits a larger phase noise, this design will address aggressively the size and power consumption reduction. Indeed we are using the efficient back-gate biasing offered by the FDSOI MOS transistor to compensate the mismatches between the different inverters of the ring oscillator to decrease jitter and phase noise. We will present the reasons which led us to use the FDSOI technology to reach the specifications of this PLL. The VCRO exhibits a 0.8 mW power consumption, with a phase noise about -94 dBc/Hz@l MHz.

关键词： nanoelectronics FDSOI UTBB VCO PLL

Human activity and climate change triggered the expansion of rocky desertification in the karst areas of Southwestern China

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Science China Earth Sciences 2021年第10期64卷 1761-1773页

作者： Chaojun CHEN Daoxian YUAN Hai CHENG Tsailuen YU Chuanchou SHEN RLawrence EDWARDS Yao WU Siya XIAO Jian ZHANG Tao WANG Ran HUANG Ziqi LIU Tingyong LI Junyun LI Chongqing Key Laboratory of Karst Environment School of Geographical SciencesSouthwest UniversityChongqing 400715China Key Laboratory of Karst Dynamics MNRGuangxiInstitute of Karst GeologyChinese Academy of Geological SciencesGuilin 541004China Yunnan Key Laboratory of Plateau Geographical Processes&Environmental Changes Faculty of GeographyYunnan Normal UniversityKunming 650500China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China High-precision Mass Spectrometry and Environment Change Laboratory(HISPEC) Department of GeosciencesTaiwan UniversityTaipei 10617China Research Center for Future Earth Taiwan UniversityTaipei 10617China Global Change Research Center Taiwan UniversityTaipei 10617China Department of Earth Sciences University of MinnesotaMinneapolisMN 55455USA Environnements et Paléoenvironnements Océaniques et Continentaux(epoc) UMR CNRS 5805Universitéde BordeauxPessac 33600France School of Karst Science Guizhou Normal UniversityGuiyang 550001China

It is conducive to the sustainable development of human beings in karst regions to research the mechanism of karst rocky desertification(KRD)expansion.Whether the large-scale KRD in southwestern China is caused by climate change or human activities is still controversial.In this study,the evolution of the KRD in southwestern China over the past 2000 years was reconstructed through the high-precisionδ^(13)C record of stalagmites from Shijiangjun(SJJ)Cave,Guizhou Province,China.Theδ^(13)C of the stalagmites from SJJ Cave exhibited heavy values from the Medieval Warm Period(MWP)to the Little Ice Age(LIA).Furthermore,theδ^(13)C records of other stalagmites and tufa from southwestern China also showed the same significant heavy trend.Because the stalagmiteδ^(13)C could record the change of ecological environment,it indicated that the consistent change of the stalagmitesδ^(13)C may record the process of KRD expansion in the karst regions of southwestern China.During the MWP,the stronger Asian summer monsoon and the northward movement of the rain belt led to a dry period in southwestern China and a wet period in northern China.In contrast,it was wet in southwestern China and dry in northern China during the LIA.In addition,after the Jing-Kang event(JK event,AD1127)occurred at the end of the Northern Song dynasty,the political and economic center of China migrated to southern China for the first time,which changed the population distribution pattern of larger population in the north and smaller population in the south.Therefore,the expansion of KRD in southwestern China was exacerbated in the MWP due to the change of climate in southwestern China,the migration of a large number of people,wars,the large-scale reclamation of arable land,and the cultivation of large areas of crops.

关键词： Karst rocky desertification Jing-Kang event Stalagmiteδ13C record Medieval Warm Period Little Ice Age

Qualitative Determination of Photodegradation Products of Progesterone and Testosterone in Aqueous Solution

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American Journal of Analytical Chemistry 2016年第1期7卷 22-33页

作者： Ladji Méité Baba Donafologo Soro Narcisse Kouassi Aboua Véronique Mambo Karim Sory Traoré Patrick Mazellier Joseh De Laat Laboratoire des Sciences de l’Environnement Unité de Formation et de Recherche des Sciences et Gestion de l’Environnement Université Nangui Abrogoua Abidjan Cote d’Ivoire cnrs-umr 5805 EPOC Laboratoire de Physico et Toxico Chimie de l’Environnement Université de Bordeaux Bordeaux France Institut de Chimie des Milieux et Matériaux de Poitiers (umr cnrs 7285) Equipe Eaux Géochimie Santé Ecole Nationale Supérieure d’Ingénieurs de Poitiers Université de Poitiers Poitiers France

Direct photochemical degradations of progesterone (PR) and testosterone (TR), two naturally produced hormones, have been conducted in non-buffered aqueous solution (pH ranging between 5.5 and 6.0). The irradiation experiments were carried out in a batch reactor upon monochromatic (254 nm) and polychromatic (λ > 290 nm) at 25°C. GLC/MS and LC/UV-DAD/MS analyses were performed to investigate phototransformation products after a solid phase extraction (SPE) step for analytes concentration. For each compound several by-products have been identified and are the same ones under both irradiation conditions. Because of the presence of the same chromophore (α, β-unsaturated group) absorbing UV radiations in both hormones, the majority of chromatographic peaks correspond to by-products formed according to identical mechanisms involving isomerization, enolization, oxidation and hydration to lead to the generation of lumiketone, cyclopentenone, spiro-hydration, oxidation and hydroxylation photoproducts.

关键词： Photoproducts Testosterone Progesterone GLC/MS LC/UV-DAD/MS

Heavy Metals Concentration in Sediments of South Brittany Waters, France: An Ecological Risk Assessment Approach

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Open Journal of Marine Science 2021年第1期11卷 55-68页

作者： Meng Chuan Ong Hui-Juan Pan Noor Azhar Mohamed Shazili David Menier Virginie Dupont Sidonie Révillon Alexandra Connell Faculty of Science and Marine Environment Universiti Malaysia Terengganu Kuala Nerus Terengganu Malaysia Institute of Oceanography and Environment Universiti Malaysia Terengganu Kuala Nerus Terengganu Malaysia Ocean Pollution and Ecotoxicology (OPEC) Research Group Universiti Malaysia Terengganu Kuala Nerus Terengganu Malaysia Institute of Earth Sciences College of Ocean Science and Resource National Taiwan Ocean University Chinese Taipei Center of Excellence for Ocean Engineering College of Engineering National Taiwan Ocean University Chinese Taipei Laboratoire Géosciences Océan (LGO) Université Bretagne Sud Vannes France Département Sciences de la Matière et de la Vie Université Bretagne Sud Vannes France umr 6538 Laboratoire Géosciences Océan Institut Universitaire Européen de la Mer Place Nicolas Copernic Plouzané France SEDISOR Institut Universitaire Européen de la Mer Place Nicolas Copernic Plouzané France Université de Bordeaux—umr cnrs 5805 epoc Pessac France

Distribution patterns of selected heavy metals content in sediments from the Bay of Quiberon and Gulf of Morbihan were studied to understand the current heavy metals contamination due to urbanization and mariculture activities in the coastal area. Therefore, a survey was conducted and 196 sediments collected were characterized for heavy metals content using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) after mix acid digestion process. The distribution maps of the concentrations of the heavy metals studied were produced as an isopleth map based on data interpolation by the ArcGIS software application. The association with the adverse effects on aquatic organisms was determined by the classification of the sediment according to the sediment quality guidelines. Therefore, two approaches were employed namely: direct comparison with Sediment Quality Guidelines (SQGs) by USEPA (United States Environmental Protection Agency) and comparison with other numerical SQGs, threshold effect level/probable effect level, and effect range low/effect range medium. In order to estimate the effect of multiple contaminations of heavy metals, the mean-ERM-quotient was calculated at each sampling point.

关键词： Heavy Metals Bay of Quiberon Gulf of Morbihan Sediment Sediment Quality Guidelines

Identification of telomere maintenance gene variations related to lung adenocarcinoma risk by genome-wide association and whole genome sequencing analyses

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Cancer Communications 2024年第2期44卷 287-293页

作者： Kouya Shiraishi Atsushi Takahashi Yukihide Momozawa Yataro Daigo Syuzo Kaneko Takahisa Kawaguchi Hideo Kunitoh Shingo Matsumoto Hidehito Horinouchi Akiteru Goto Takayuki Honda Kimihiro Shimizu Masahiro Torasawa Daisuke Takayanagi Motonobu Saito Akira Saito Yuichiro Ohe Shun-ichi Watanabe Koichi Goto Masahiro Tsuboi Katsuya Tsuchihara Sadaaki Takata Tomomi Aoi Atsushi Takano Masashi Kobayashi Yohei Miyagi Kazumi Tanaka Hiroyuki Suzuki Daichi Maeda Takumi Yamaura Maiko Matsuda Yoko Shimada Takaaki Mizuno Hiromi Sakamoto Teruhiko Yoshida Yasushi Goto Tatsuya Yoshida Taiki Yamaji Makoto Sonobe Shinichi Toyooka Kazue Yoneda Katsuhiro Masago Fumihiro Tanaka Megumi Hara Nobuo Fuse Satoshi S.Nishizuka Noriko Motoi Norie Sawada Yuichiro Nishida Kazuki Kumada Kenji Takeuchi Kozo Tanno Yasushi Yatabe Kuniko Sunami Tomoyuki Hishida Yasunari Miyazaki Hidemi Ito Mitsuhiro Amemiya Hirohiko Totsuka Haruhiko Nakayama Tomoyuki Yokose Kazuyoshi Ishigaki Toshiteru Nagashima Yoichi Ohtaki Kazuhiro Imai Ken Takasawa Yoshihiro Minamiya Kazuma Kobayashi Kenichi Okubo Kenji Wakai Atsushi Shimizu Masayuki Yamamoto Motoki Iwasaki Koichi Matsuda Johji Inazawa Yuichi Shiraishi Hiroyoshi Nishikawa Yoshinori Murakami Michiaki Kubo Fumihiko Matsuda Yoichiro Kamatani Ryuji Hamamoto Keitaro Matsuo Takashi Kohno Division of Genome Biology National Cancer Center Research InstituteTokyoJapan Department of Clinical Genomics National Cancer Center Research InstituteTokyoJapan Laboratory for Statistical Analysis Center for Integrative Medical SciencesRIKENYokohamaJapan Department of Genomic Medicine Research InstituteNational Cerebral and Cardiovascular CenterOsakaJapan Laboratory for Genotyping Development Center for Integrative Medical SciencesRIKENYokohamaJapan Center for Antibody and Vaccine Therapy Research HospitalInstitute of Medical ScienceThe University of TokyoTokyoJapan Department of Medical Oncology and Cancer Center and Center for Advanced Medicine against CancerShiga University of Medical ScienceOtsuJapan Division of Medical AI Research and Development National Cancer Center Research InstituteTokyoJapan Center for Genomic Medicine Graduate School of MedicineKyoto UniversityKyotoJapan Department of Medical Oncology Japanese Red Cross Medical CenterTokyoJapan Department of Thoracic Oncology National Cancer Center Hospital EastJapan Department of Thoracic Oncology National Cancer Center HospitalTokyoJapan Department of Cellular and Organ Pathology Graduate School of MedicineAkita UniversityAkitaJapan Department of Respiratory Medicine Tokyo Medical and Dental UniversityBunkyo-kuTokyoJapan Division of General Thoracic Surgery Department of SurgeryShinshu University School of MedicineMatsumotoNaganoJapan Department of General Surgical Science Division of General Thoracic SurgeryGunma University Graduate School of MedicineIntegrative Center of General SurgeryGunma University HospitalGunmaJapan Department of Gastrointestinal Tract Surgery Fukushima Medical University School of MedicineFukushimaJapan StaGen Co. LtdTokyoJapan Division of Thoracic Surgery National Cancer Center HospitalTokyoJapan Department of Thoracic Surgery National Cancer Center Hospital EastChibaJapan Division of Translational Informatics Exploratory Oncology Research and Clinical Trial Center(EPOC

Dear editor,Lung carcinoma is responsible for the highest fatal-ity rate among cancer-related deaths globally,with lung adenocarcinoma(LADC)emerging as the prevailing sub-type.

关键词： adenocarcinoma lung Lung

HER2 heterogeneity is a poor prognosticator for HER2-positive gastric cancer

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World Journal of Clinical Cases 2019年第15期7卷 1964-1977页

作者： Akio Kaito Takeshi Kuwata Masanori Tokunaga Kohei Shitara Reo Sato Tetsuo Akimoto Takahiro Kinoshita Department of Gastric Surgery National Cancer Center Hospital EastKashiwa 277-8577Japan Department of Pathology and Clinical Laboratories National Cancer Center Hospital EastKashiwa 277-8577Japan Department of Gastrointestinal Oncology National Cancer Center Hospital EastKashiwa 277-8577Japan Exploratory Oncology Research&Clinical Trial Center(epoc) National Cancer Center Hospital EastKashiwa 277-8577Japan Juntendo University Graduate School of Medicine Tokyo 163-8001Japan Department of Radiation Oncology National Cancer Center Hospital EastKashiwa 277-8577Japan

BACKGROUND The clinical significance of intratumoral human epidermal growth factor receptor 2(HER2)heterogeneity is unclear for HER2-positive gastric cancer,although it has been reported to be a significant prognosticator for HER2-positive breast cancer,which has received trastuzumab-based chemotherapy.AIM To clarify the clinical significance of intratumoral HER2 heterogeneity for HER2-positive gastric cancer,which has received trastuzumab-based chemotherapy.METHODS Patients with HER2-positive unresectable or metastatic gastric cancer who received trastuzumab-based chemotherapy as a first line treatment were included.The patients were classified into two groups according to their intratumoral HER2 heterogeneity status examined by immunohistochemistry(IHC)on endoscopic biopsy specimens before treatment,and their clinical response to chemotherapy and survival were compared.RESULTS A total of 88 patients were included in this study,and HER2 heterogeneity was observed in 23(26%)patients(Hetero group).The overall response rate was significantly better in patients without HER2 heterogeneity(Homo group)(Homo vs Hetero:79.5%vs 35.7%,P=0.002).Progression-free survival of trastuzumab-based chemotherapy was significantly better in the Homo group(median,7.9 vs 2.5 mo,HR:1.905,95%CI:1.109-3.268).Overall survival was also significantly better in the Homo group(median survival time,25.7 vs 12.5 mo,HR:2.430,95%CI:1.389-4.273).Multivariate analysis revealed IHC HER2 heterogeneity as one of the independent poor prognostic factors(HR:3.115,95%CI:1.610-6.024).CONCLUSION IHC of HER2 heterogeneity is the pivotal predictor for trastuzumab-based chemotherapy.Thus,HER2 heterogeneity should be considered during the assessment of HER2 expression.

关键词： Human epidermal growth factor receptor 2 Heterogeneity Trastuzumab Gastric cancer Chemotherapy