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环保绝缘气体介电强度预测方法评估

电工技术学报 2023年第S1期38卷 214-221页

作者：周文俊邱睿郑宇 pascal Brault 电网环境保护全国重点实验室(武汉大学) 武汉430072 武汉大学电气与自动化学院武汉430072 法国国家科学研究中心-奥尔良大学GREMI实验室奥尔良45067

为明确各类气体介电强度预测方法的准确性,基于9种气体(N_(2)、CO_(2)、N_(2)O、CF_(4)、SO_(2)F_(2)、c-C_(4)F_(8)、C_(3)F_(8)、C_5F_(10O)和C_(4)F_(7)N)在50 Hz工频交流电场下测得的相对介电强度对5种预测方法进行了评估。结果表明,各方法预测准确性与其给出的可决系数R~2不一致。这主要与其使用的样本数据测试条件不统一、同一气体的相对介电强度不一致有关。当修正上述问题后,各方法准确性得到提升,并与其R~2相符。分子参数的丰富和放电理论的介入可使预测方法准确性提升。使用样本外气体进行验证的方法,其预测结果在修正前后都具有较高的准确性;使用基团贡献法的预测方法也具有上述特性。通过上述评估结果可知,样本中的气体数据需在统一条件下获得,并根据试验条件和样本分子特征确定预测方法的适用范围。放电理论、分子几何特征和新分子参数的引入有助于提高预测模型的准确性。模型验证和基团贡献法可提高预测方法对样本数据的包容性。

关键词：环保绝缘气体介电强度预测构效关系(QSPR) 气体绝缘输电管道(GIL)

On-surface activation of benzylic C-H bonds for the synthesis of pentagon-fused graphene nanoribbons

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Nano Research 2021年第12期14卷 4754-4759页

作者： Xiushang Xu Marco di Giovannantonio José I.Urgel Carlo A.Pignedoli pascal Ruffieux Klaus Müllen Roman Fasel Akimitsu Narita Present address:Istituto di Struttura della Materia-CNR(ISM-CNR) via Fosso del Cavaliere 10000133RomaItaly Present address:IMdEA Nanoscience C/Faraday 9Campus de Cantoblanco28049MadridSpain Max Planck Institute for Polymer Research 55128MainzGermany Empa Swiss Federal Laboratories for Materials Science and Technologynanotech@surfaces Laboratory8600DübendorfSwitzerland Organic and Carbon Nanomaterials Unit Okinawa Institute of Science and Technology Graduate University1919-1 TanchaOnna-sonKunigami-gunOkinawa904-0495Japan Institute of Physical Chemistry Johannes Gutenberg University MainzDuesbergweg 10-1455128MainzGermany

Graphene nanoribbons (GNRs) have potential for applications in electronic devices. A key issue, thereby, is the fine-tuning of their electronic characteristics, which can be achieved through subtle structural modifications. These are not limited to the conventional armchair, zigzag, and cove edges, but also possible through incorporation of non-hexagonal rings. On-surface synthesis enables the fabrication and visualization of GNRs with atomically precise chemical structures, but strategies for the incorporation of non-hexagonal rings have been underexplored. Herein, we describe the on-surface synthesis of armchair-edged GNRs with incorporated five-membered rings through the C-H activation and cyclization of benzylic methyl groups. Ortho-Tolyl-substituted dibromobianthryl was employed as the precursor monomer, and visualization of the resulting structures after annealing at 300 °C on a gold surface by high-resolution noncontact atomic force microscopy clearly revealed the formation of methylene-bridged pentagons at the GNR edges. These persisted after annealing at 340 °C, along with a few fully conjugated pentagons having singly-hydrogenated apexes. The benzylic methyl groups could also migrate or cleave-off, resulting in defects lacking the five-membered rings. Moreover, unexpected and unique structural rearrangements, including the formation of embedded heptagons, were observed. despite the coexistence of different reaction pathways that hamper selective synthesis of a uniform structure, our results provide novel insights into on-surface reactions en route to functional, non-benzenoid carbon nanomaterials.

关键词： graphene nanoribbons on-surface synthesis scanning-tunneling microscope noncontact atomic force microscope C-H activation

Homozygosity for the Cd1E★02 allele is associated with a resistance to Plasmodium falciparum malaria infection in Gabonese school children

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Asian Pacific Journal of Tropical Medicine 2017年第2期10卷 195-198页

作者： Landry-Erik Mombo Francine Ntoumi Cyrille Bisseye Rajendranath Ramasawmy pascal Millet Ryad Tamouza Centre International de Recherches Medicales de Franceville(CIRMF) BP 769FrancevilleGabon INSERM U458 Hopital Robert Debre48 Bd Serurier75019 ParisFrance Laboratoire d'Immunologie et d'Histocompatibilite AP-HP IUH and INSERM U662Hopital Saint-LouisParisFrance

Objective:To explore the possible association between polymorphisms in Cd1 genes and both asymptomatic and mild Plasmodium falciparum ***:Two clusters of 85 school children,from the village of dienga(Gabon) were *** first group was analysed for the prevalence and the multiplicity of asymptomatic Plasmodium falciparum infection,whereas the second group was screened for the frequency of malarial ***:Our findings showed that homozygosity for the Cd1E★02 allele was associated with a low frequency of malarial ***,a strong association between Cd1E★02 homozygotes and the resistance to multiple malarial attacks was *** Cd1A★01 allele showed a weak association with a small number of malarial ***:Our results suggest a possible role of Cd1E polymorphisms in malaria protection among school children and that Cd1e molecules are involved in anti-malarial immunity.

关键词： Cd1E Cd1A Malaria GPI Gabon

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Molecular Plant 2012年第1期5卷 115-130页

作者： Stefanie Ranf Julia Grimmer Yvonne P6schl pascal Pecher delphine Chinchilla dierk Scheel Justin Lee Leibniz Institute of Plant Biochemistry Stress and Developmental Biology Weinberg 3 D-06120 Halle Germanyb Present address： Institute of Biochemistry and Biotechnology Martin Luther University Halle-Wittenberg Weinbergweg 22 D-06120 Halle Germany Institute of Computer Science Martin Luther University Halle-Wittenberg Von-Seckendorff-Platz 1 D-06120 Halle Germany Zurich-Basel Plant Science Center Botanical Institute University of Basel Hebelstrasse 1 4056 Basel Switzerland

Calcium acts as a second messenger for signaling to a variety of stimuli including MAMPs （Microbe-Associated Molecular Patterns）, such as fig22 and elf18 that are derived from bacterial flagellin and elongation factor Tu, respectively. Here, Arabidopsis thaliana mutants with changed calcium elevation （cce） in response to fig22 treatment were isolated and characterized. Besides novel mutant alleles of the fig22 receptor, FLS2 （Flagellin-Sensitive 2）, and the receptor-associated kinase, BAK1 （Brassinosteroid receptor 1-Associated Kinase 1）, the new cce mutants can be categorized into two main groups--those with a reduced or an enhanced calcium elevation. Moreover, cce mutants from both groups show differ- ential phenotypes to different sets of MAMPs. Thus, these mutants will facilitate the discovery of novel components in early MAMP signaling and bridge the gaps in current knowledge of calcium signaling during plant-microbe interactions. Last but not least, the screening method is optimized for speed （covering 384 plants in 3 or 10 h） and can be adapted to genetically dissect any other stimuli that induce a change in calcium levels.

关键词： Calcium signaling/transport defense responses plant-microbe interactions signal transduction Arabidopsis.

different profiles of cytokine expression during mild and severe acute pancreatitis

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World Journal of Gastroenterology 2010年第15期16卷 1845-1853页

作者： Zilvinas dambrauskas Nathalia Giese Antanas Gulbinas Thomas Giese pascal O Berberat Juozas Pundzius Giedrius Barauskas Helmut Friess Laboratory for Research of digestive System Institute for Biomedical ResearchEiveniu Str. 2 50009 Kaunas Lithuania department of Surgery Kaunas University of MedicineEiveniu Str. 2 50009 Kaunas Lithuania department of Surgery Heidelberg UniversityIm Neuenheimer Feld 110D-69120 Heidelberg Germany Institute for Immunology Heidelberg UniversityIm Neuenheimer Feld 305D-69120 Heidelberg Germany department of Surgery University of Technology MunichIsmaninger Str. 2281675 Munich Germany department of Surgery Kaunas University of MedicineEiveniu Str. 250009 Kaunas Lithuania

AIM:To study secretion patterns of proand anti-in-flammatory cytokines, and activation of various cellular subsets of leukocytes in peripheral ***: We have conducted a prospective obser-vational study. One hundred and eight patients with a diagnosis of acute pancreatitis and onset of the disease within last 72 h were included in this study. The mRNA expression of 25 different types of cytokines in white blood cells was determined by quantitative real time polymerase chain reaction. Levels of 8 different cytokines in blood serum were measured by enzymelinked immunosorbent assay. Clinical data and cytokine expression results were subjected to statistical ***: Severe and necrotizing acute pancreatitis (AP) is characterized by the significant depletion of circulating lymphocytes. Severe acute pancreatitis is as-sociated with a typical systemic inflammatory response syndrome and over-expression of pro-inflammatory cy-tokines [interleukin (IL)-6, IL-8, macrophage migration inhibitory factor (MIF)]. Serum IL-6 and MIF concentra-tions are the best discriminators of severe and necrotiz-ing AP as well as possible fatal outcome during the early course of the disease. CONCLUSION: deregulation of cellular immune sys-tem is a key event leading to severe and necrotizing AP. IL-6 and MIF could be used as early predictors of complications.

关键词： Acute pancreatitis Cytokines Prognostic factors

Punch‑excised explants of bovine mammary gland to model early immune response to infection

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2649-2662页

作者： Pablo Gomes Noleto Florence B.Gilbert Christelle Rossignol Patricia Cunha Pierre Germon pascal Rainard Rodrigo Prado Martins ISP INRAEUniversitéde ToursUMR1282NouzillyFrance

Background Mammary gland(MG)infections(mastitis)are frequent diseases of dairy cows that affect milk quality,animal welfare and farming *** infections are commonly associated with the bacteria Escherichia coli and Staphylococcus *** in vitro models have been used to investigate the early response of the MG to bacteria,but the role of the teat in mastitis pathogenesis has received less *** this study,we used punch-excised teat tissue as an ex vivo model to study the immune mechanisms that arise early during infection when bacteria have entered the *** Cytotoxicity and microscopic analyses showed that bovine teat sinus explants have their morphology and viability preserved after 24 h of culture and respond to ex vivo stimulation with TLR-agonists and *** and *** trigger stronger inflammatory response in teat when compared to LTA and ***,leading to a higher produc-tion of IL-6 and IL-8,as well as to an up-regulation of proinflammatory *** also demonstrated that our ex vivo model can be applied to frozen-stored *** In compliance with the 3Rs principle(replacement,reduction and refinement)in animal experimenta-tion,ex vivo explant analyses proved to be a simple and affordable approach to study MG immune response to *** model,which better reproduces organ complexity than epithelial cell cultures or tissue slices,lends itself particularly well to studying the early phases of the MG immune response to infection.

关键词： Bovine teat Escherichia coli Explant Mastitis Staphylococcus aureus 3Rs

African eggplant(Solanum anguivi Lam.)fruit with bioactive polyphenolic compounds exerts in vitro antioxidant properties and inhibits Ca^(2+)-induced mitochondrial swelling

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Asian Pacific Journal of Tropical Biomedicine 2013年第10期3卷 757-766页

作者： Olusola Olalekan Elekofehinti Jean Paul kamdem Aline Augusti Bolingon Margareth Linde Athayde Seeger Rodrigo Lopes Emily Pansera Waczuk Ige Joseph Kade Isaac Gbadura Adanlawo Joao Batista Teixeira Rocha department of Biochemistry Adekunle Ajasin UniversityAkungbaOndo StateNigeria Postgraduate Programme in Biochemical Toxicology Department of ChemistryCCNE.Federal University of Santa Maria.Campus CamobiSanta MariaRS.97105-900Brazil Postgraduate Programme in Pharmaceutical Sciences Federal University of Santa MariaCampus CamohiSanta MariaRS97105-900.Brazil Toxicologia de Produtos Naturais e Sinteticos.Universidade Federal do Pampa CEP 97500-970 UruguaianaRSBrazil department of Biochemistry Federal University of TechnologyAkureOndo StateNigeria department of Biochemistry University of Ado EkitiEkiti State.Nigeria

Objective:To evaluate the antioxidant and radical scavenging activities of Solanum anguivi fruit(SAG)and its possible effect on mitochondrial permeability transition pore as well as mitochondrial membrane potential(△Ψ_m)isolated from rat ***:Antioxidant activity of SAG was assayed by using 2,2-diphenyl-1-picrylhydrazyl(dPPH),reducing power,iron chelation and ability to inhibit lipid peroxidation in both liver and brain homogenate of ***,the effect of SAG on mitochondrial membrane potential and mitochondrial swelling were *** and quantification of bioactive polyphenolics was done by ***:SAG exhibited potent and concentration dependent free radical-scavenging activity(IC_(50)/dPPH=275.03±7.8μg/mL).Reductive and iron chelation abilities also increase with increase in SAG *** also inhibited peroxidation of cerebral and hepatic lipids subjected to iron oxidative *** protected against Ca^(2+)(110μmol/L)-induced mitochondrial swelling and maintained the△Ψ_*** analysis revealed the presence of gallic acid[(17.54±0.04)mg/g],chlorogenic acid(21.90±0.02 mg/g),caffeic acid(16.64±0.01 mg/g).rutin[(14.71±0.03)mg/g]and quercetin[(7.39±0.05)mg/g].Conclusions:These effects could be attributed to the bioactive polyphenolic compounds present in the *** results suggest that SAG extract is a potential source of natural antioxidants that may be used not only in pharmaceutical and food industry but also in the treatment of diseases associated with oxidative stress.

关键词： Solanum anguivi fruit Antioxidant activity Oxidative stress Mitochondrial swelling HPLC Polyphenolic compounds MPTP

Understanding the Variability of Z-R Relationships Caused by Natural Variations in Raindrop Size distributions(dSd):Implication of drop Size and Number

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Atmospheric and Climate Sciences 2011年第3期1卷 147-164页

作者： Abe d.Ochou Eric-pascal Zahiri Bakary Bamba Manlandon Koffi Laboratoire de Physique de l’Atmosphere et Mecanique des fluides(LAPA-MF) Universite de Cocody-AbidjanAbidjanCote d’Ivoire Institut National Polytechnique Houphouet-Boigny YamoussoukroCote d’Ivoire

In the issue of rainfall estimation by radar through the necessary relationship between radar reflectivity Z and rain rate R (Z-R), the main limitation is attributed to the variability of this relationship. Indeed, several pre-vious studies have shown the great variability of this relationship in space and time, from a rainfall event to another and even within a single rainfall event. Recent studies have shown that the variability of raindrop size distributions and thereby Z-R relationships is therefore, more the result of complex dynamic, thermody-namic and microphysical processes within rainfall systems than a convective/stratiform classification of the ground rainfall signature. The raindrop number and size at ground being the resultant of various processes mentioned above, a suitable approach would be to analyze their variability in relation to that of Z-R relation-ship. In this study, we investigated the total raindrop concentration number NT and the median volume di-ameter d0 used in numerous studies, and have shown that the combination of these two ‘observed’ parame-ters appears to be an interesting approach to better understand the variability of the Z-R relationships in the rainfall events, without assuming a certain analytical raindrop size distribution model (exponential, gamma, or log-normal). The present study is based on the analysis of disdrometer data collected at different seasons and places in Africa, and aims to show the degree of the raindrop size and number implication in regard to the Z-R relationships variability.

关键词： Raindrop Size distribution Radar Reflectivity Factor Rain Rate Median Volume diameter Total Number of drops Per Unit Volume Z-R Relationship Convective Rain Stratiform Rain Squall Lines Thunderstorm

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采用KP和TMP抄制多层纸板

国外造纸 1992年第3期11卷 21-25页

作者： Z.Koran d.P.kamdem 赵涛

多层纸板传统上是面层和底层分别用漂白和未漂KP、芯层用成本较低的原料如SGW制成的,这种结构型式的目的是通过提高纸浆得率,以较低的配浆成本发挥出同样或更好的纸板特性。许多研究人员正是考虑到这一原则,在纸板配浆中渗入包括SGW、C... 详细信息

多层纸板传统上是面层和底层分别用漂白和未漂KP、芯层用成本较低的原料如SGW制成的,这种结构型式的目的是通过提高纸浆得率,以较低的配浆成本发挥出同样或更好的纸板特性。许多研究人员正是考虑到这一原则,在纸板配浆中渗入包括SGW、CTMP、TMP以及某些阔叶木在内的高得率浆,通过不断的尝试,使现在多层纸板的生产成为工业现实。

关键词：多层纸板纸板 KP浆 TMP浆抄制