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Stable isotope tracers identify sources and transformations of mercury in rice (Oryza sativa L.) growing in a mercury mining area

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Fundamental Research 2021年第3期1卷 259-268页

作者： Jiang Liu Bo Meng Alexandre.J.poulain Qiyi Meng Xinbin Fenga State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China Biology Department University of Ottawa30 Marie CurieOttawa ON K1N 6N5Canada Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi'an 710061China

Methylmercury (MeHg) contaminated rice is a global issue, particularly in mercury-polluted areas, posing a potential threat to human health. The sources and transformations of mercury (Hg) species in rice are critical points that are not yet fully understood. In this study, field experimental pots together with a stable Hg isotope tracing technique were used to provide direct evidence of the sources and transformations of Hg species in rice plants. Enriched inorganic Hg (IHg) isotope (200Hg(NO3)2) was spiked into paddy soils, and the concentrations of inorganic Hg tracer (I200Hg), MeHg tracer (Me200Hg), and ambient Hg species (IHg and MeHg) were measured in the tissues of rice plants and their corresponding soil samples during the rice growing season. Here, we show that, in addition to the atmosphere, the soil is an important source of IHg to rice grains and was previously largely underestimated. We also show that MeHg is formed in paddy soil via microbial IHg methylation, absorbed through the rice root, translocated from the root to above-ground parts, and finally accumulated in rice grains. Although in vivo methylation of IHg in rice plants is unlikely to occur during the rice growing season, we observed in vivo demethylation of MeHg in the above-ground parts of rice plants, possibly via photolytic demethylation. Promoting in vivo demethylation of MeHg may be an effective approach to mitigate MeHg accumulation in rice grains.

关键词： Rice Hg isotope tracer Source Translocation Methylation/demethylation

Hand-Sewn Running Barbed Suture versus Endoscopic Stapler Closure of the Mesenteric Defects in Retrocolic and Retrogastric RYGB: A Comparative Case-Matched Study

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Surgical Science 2015年第8期6卷 346-351页

作者： v. Simonelli G. Orlando A. Zolotas C. Arendt L. Arru v. poulain J. S. Azagra M. Goergen Centre Hospitalier de Luxembour Luxembourg Ville Luxembourg

Background: Obesity is nowadays a major health concern in Western countries and the number of bariatric surgical procedures being performed worldwide is vertiginously rising. The Laparoscopic Roux-en-Y gastric bypass (LRYGB) has become the gold standard bariatric procedure. The retrocolic retrogastric approach is closer to normal anatomy and it is associated to a lower rate of anastomotic leak, a lower rate of gastrojejunal stricture and a lower rate of marginal ulcers;therefore the problem of small bowel obstruction due to internal hernia (IH) has to be faced. The meticulous closure of all possible mesenteric defects with running, non-absorbable sutures may reduce the rate of this complication, but it can be challenging for the surgeon and it rises the operating time (OT). This study has conducted in a context of optimization of our “Fast Track-type” recovery protocol and it aims to compare the rate of early IH and the OT difference when mesenteric defects are closed using running non-absorbable barbed suture or an endoscopic stapler. Materials and Methods: From December 2014 to February 2015 a single-surgeon consecutive series of 22 patients undergoing retrocolic restrogastric LRYBP in our high volume obesity centre has been retrospectively extrapolated from our prospective longitudinal database. We recorded the overall OT and relative rate of IH in patients who received a 15-cm non-absorbable v-LocTM1 (group A, 11 patients) or EndopathTM EMS, endoscopic multifeed stapler2 (group B, 11 patients) defect. Results: The mean OT was 77.36 minutes in the group A and 60.90 minutes in the group B (P value 0.066). 0 patients (0%) in the group A versus 4 patients (36.3%) in the group B developed IH within 30 days (two-tailed P value at chi-square test: 0.02). Conclusion: Early rate of small bowel obstruction due to IH is extremely higher with the use of an endoscopic stapler instead of non-absorbable barber suture and there is not significant difference in the OT;more prosp

关键词： Laparoscopy Gastric Bypass Fastrack Internal Hernia

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掺镨氟化镓铟玻璃的研究

硅酸盐学报 1998年第1期26卷 103-108页

作者：张国寅 Poual.,M 武汉工业大学

合成了一族新的氟化镓铟玻璃，研究了ＩｎＦ３－ＰｂＦ２－ＺｎＦ２－ＣｄＦ２（ＢａＦ２）体系和ＧａＦ３－ＣｄＦ２－ＰｂＦ２（ＺｎＦ２）体系的玻璃形成区域．经玻璃组分试验研究得到了稳定的３０ＰｂＦ２－２０ＧａＦ３－１５Ｉｎ... 详细信息

合成了一族新的氟化镓铟玻璃，研究了ＩｎＦ３－ＰｂＦ２－ＺｎＦ２－ＣｄＦ２（ＢａＦ２）体系和ＧａＦ３－ＣｄＦ２－ＰｂＦ２（ＺｎＦ２）体系的玻璃形成区域．经玻璃组分试验研究得到了稳定的３０ＰｂＦ２－２０ＧａＦ３－１５ＩｎＦ３－２０ＣｄＦ２－１５ＺｎＦ２（简化为ＰＧＩＣＺ）玻璃，通过优化细调组分，可制得１４ｍｍ厚块玻璃和具有芯皮结构的光纤．红外和Ｒａｍａｎ光谱研究结果表明：ＰＧＩＣＺ玻璃具有较氟锆酸盐（简化为ＺＢＬＡＮ）玻璃更宽的红外透过范围和更低的声子能量．Ｐｒ３＋掺杂ＰＧＩＣＺ玻璃的１Ｇ４能级寿命可达２１０μｓ，其量子效率为７％，是通常ＺＢＬＡＮ玻璃的一倍，故它是最可能作为掺镨光纤放大器的实用化体系之一．

关键词：氟化镓玻璃氟化铟错掺杂玻璃

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Watt-level and spectrally flat mid-infrared supercontinuum in fluoroindate fibers

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Photonics Research 2018年第6期6卷 609-613页

作者： FRANCIS THEBERGE NANCY BERUBE SAMUEL poulain SOLENN COXIC LOUIS-RAFAEL ROBICHAUD MARTIN BERNIER REAL vALLEE Defence R&D Canada Valcartier Centre Quebec G3J1X5 Canada Le verre Fluore Campus KerLann F-35170 Bruz Brittany France Center for Optics Photonics and Lasers (COPL) Universite Laval Quebec G1V0A6 Canada

We report on infrared supercontinuum （SC） generation in step-index fluoroindate-based fiber by using an all-fiber laser source. In comparison to widely used ZBLAN fibers for high-power mid-infrared （MIR） SC generation, fluoroindate fibers have multiphoton absorption edges at significandy longer wavelengths and can sustain similar intensities. Recent developments highlighted in the present study allowed the production of fluoroindate fibers with MIR background loss of 2 dB/km, which is similar to or even better than ZBLAN fibers. By using an all-fiber picosecond laser source based on an erbium amplifier followed by a thulium power amplifier, we demonstrate the generation of 1.0 W infrared SC spanning over 2.25 octaves from 1 μm to 5 μm. The generated MIR SC also exhibits high spectral flatness with a 6 dB spectral bandwidth from 1.91 μm to 4.77 μm and an average power two orders of magnitude greater than in previous demonstrations with a similar spectral distribution.

关键词： Fiber optics infrared Nonlinear optics fibers Supercontinuum generation

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暗电流低和电容小的快速GaInAsP P-p-I-N光电二极管

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微纳电子技术 1983年第3期 48-51页

作者： poulain.P 李华

用与InP匹配的GaInAsP(λ;（?）1.33μm)制作了一种所谓P-p-I-N结构的新型光电二极管。在-20v偏压下,在InP中2μm厚的I区完全耗尽。在这个偏压下,对面积为0.8×10;cm;的二极管,电容小于0.5pF,暗电流小于10pA,内量子效率接近100％和响应... 详细信息

用与InP匹配的GaInAsP(λ;（?）1.33μm)制作了一种所谓P-p-I-N结构的新型光电二极管。在-20v偏压下,在InP中2μm厚的I区完全耗尽。在这个偏压下,对面积为0.8×10;cm;的二极管,电容小于0.5pF,暗电流小于10pA,内量子效率接近100％和响应时间小于200ps。对面积为1.5×10;cm;的二极管,在-20v下测得暗电流为3.5pA。相应的电流密度(J;<2.5×10;A/cm;)是目前报导的用GaInAsP合金所作器件的最小值。

关键词：光电二极管响应时间 GaInAsP P-p-I-N 暗电流电容

Optic nerve injury-induced regeneration in the adult zebrafish is accompanied by spatiotemporal changes in mitochondrial dynamics

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Neural Regeneration Research 2023年第1期18卷 219-225页

作者： An Beckers Luca Masin Annelies van Dyck Steven Bergmans Sophie vanhunsel Anyi Zhang Tine verreet Fabienne Epoulain Karl Farrow Lieve Moons Neural Circuit Development and Regeneration Research Group Animal Physiology and Neurobiology SectionDepartment of BiologyKatholieke Universiteit LeuvenLeuvenBelgium poulain Lab Department of Biological SciencesUniversity of South CarolinaColumbiaSCUSA Neuro-Electronics Research Flanders Vlaams Instituut voor Biotechnologie(VIB)LeuvenBelgium Leuven Brain Institute LeuvenBelgium Imec LeuvenBelgium

Axonal regeneration in the central nervous system is an energy-intensive *** contrast to mammals,adult zebrafish can functionally recover from neuronal *** raises the question of how zebrafish can cope with this high energy *** previously showed that in adult zebrafish,subjected to an optic nerve crush,an antagonistic axon-dendrite interplay exists wherein the retraction of retinal ganglion cell dendrites is a prerequisite for effective axonal *** postulate a‘dendrites for regeneration’paradigm that might be linked to intraneuronal mitochondrial reshuffling,as ganglion cells likely have insufficient resources to maintain dendrites and restore axons ***,we characterized both mitochondrial distribution and mitochondrial dynamics within the different ganglion cell compartments(dendrites,somas,and axons)during the regenerative *** nerve crush resulted in a reduction of mitochondria in the dendrites during dendritic retraction,whereafter enlarged mitochondria appeared in the optic nerve/tract during axonal *** dendritic regrowth in the retina,mitochondrial density inside the retinal dendrites returned to baseline ***,a transient increase in mitochondrial fission and biogenesis was observed in retinal ganglion cell somas after optic nerve *** together,these findings suggest that during optic nerve injury-induced regeneration,mitochondria shift from the dendrites to the axons and back again and that temporary changes in mitochondrial dynamics support axonal and dendritic regrowth after optic nerve crush.

关键词： axonal regeneration central nervous system dendrite remodeling energy metabolism fission mitochondria mitochondrial trafficking optic nerve crush retina zebrafish

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运用超声波剪切成像技术进行移植肾定量弹性成像的初步研究

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国际医学放射学杂志 2012年第6期 607-607页

作者： N.Grenier S.poulain S.Lepreux J.L.Gennisson B.Dallaudière Y.Lebras 陈莉 CHU Bordeaux-Groupe Hospitalier Pellegrin Service de RadiologiePlace Amélie Raba Léon33076 BordeauxFrance

目的评估超声波剪切成像技术(SSI)定量分析移植肾弹性的可靠程度,以及与肾实质病理变化的关系。资料与方法本实验共43例移植肾受者(女22例,男21例;年龄18～70岁,平均51岁)接受SSI弹性成像检查,且均进行肾组织活检。移植肾皮质弹性的定... 详细信息

目的评估超声波剪切成像技术(SSI)定量分析移植肾弹性的可靠程度,以及与肾实质病理变化的关系。资料与方法本实验共43例移植肾受者(女22例,男21例;年龄18～70岁,平均51岁)接受SSI弹性成像检查,且均进行肾组织活检。移植肾皮质弹性的定量测量由2名放射科医师完成,并用杨氏模量(kPa)来表示。使用Kruskal-Wallis检验和Bland-Altman统计分析评估观察者的可重复性,运用半定量Banff评分评价组织弹性值与临床、生物和病理资料之间的相关性。肾间质纤维化程度采用半定量Banff评分和图像定量两种方法进行评估。结果观察者测定的肾皮质弹性的变异系数分别为20%和12%。肾皮质硬度和临床参数与肾脏半定量Banff得分及肾间质纤维化的水平没有相关性。但是,肾皮质硬度在慢性病变和所有肾脏基础病变的Banff总得分呈显著相关(分别为R=0.34,P=0.05和R=0.41,P=0.03)。结论 SSI定量测量移植肾硬度,是一种无创的整体评估组织恶化程度的检测手段,具有前瞻性意义。

关键词：肾脏移植弹性成像超声肾纤维化