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Accumulation of Flavonoids in an ntra ntrb Mutant Leads to Tolerance to UV-C

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Molecular Plant 2009年第2期2卷 249-258页

作者： Talaat Bashandy Ludivine Taconnat Jean-Pierre Renou Yves meyer Jean-Philippe Reichheld Laboratoire Genome et Developpement des Plantes Universite de Perpignan UMR CNRS 5096 52 avenue Paul Alduy 66860 Perpignan France Unite de Recherche en Genomique Vegetale 91057 Evry cedex France

NADPH-dependent thioredoxin reductases （NTRs） are key regulatory enzymes determining the redox state of thioredoxins. There are two genes encoding NTRs （NTRA and NTRB） in the Arabidopsis genome, each encoding a cytosolic and a mitochondrial isoform. A double ntra ntrb mutant has recently been characterized and shows slower plant growth, slightly wrinkled seeds and a remarkable hypersensitivity to buthionine sulfoximine （BSO）, a specific inhibitor of gluta- thione biosynthesis. In this paper, we demonstrate that this mutant also accumulates higher level of flavonoids. Analysis of transcriptome data showed that several genes of the flavonoid pathway are overexpressed in the ntra ntrb mutant. Accumulation of flavonoids is generally considered a hallmark of plant stress. Nevertheless, no elevation of the expression of genes encoding ROS-detoxification enzymes was observed, suggesting that the ntra ntrb plants do not suffer from oxidative disease. Another hypothesis suggests that flavonoids are specifically synthesized in the ntra ntrb mutant in order to rescue the inactivation of NTR. To test this, the ntra ntrb mutant was crossed with transparent testa 4 （tt4） plants with a mutation in the gene encoding the first enzyme in flavonoid biosynthesis. As ntra ntrb plants are more resistant to UV-C treatment than wild-type plants, this higher resistance was abolished in the ntra ntrb tt4 mutant, suggesting that accumulation of flavonoids in the ntra ntrb mutant protects plants against UV-light.

关键词： abiotic/environmental stress oxidative and photo-oxidative stress secondary metabolism - phenylpropanoidsand phenolics gene expression Arabidopsis.

全容积IVIM直方图分析对乳腺良恶性病变的影响

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中国CT和MRI杂志 2024年第3期22卷 82-85页

作者：李俊蔡小丽吴奇川牟方胜重庆大学附属三峡医院放射科重庆404000

目的探讨全容积测量体素内不相干运动(IVIM)直方图参数对乳腺良恶性病变的诊断价值。方法收集我院2021年2月-2022年10月术前行多模态磁共振检查并获得病理的153例女性共158例肿瘤。利用直方图处理软件得到肿瘤IVIM(D、D*、f)的直方图... 详细信息

目的探讨全容积测量体素内不相干运动(IVIM)直方图参数对乳腺良恶性病变的诊断价值。方法收集我院2021年2月-2022年10月术前行多模态磁共振检查并获得病理的153例女性共158例肿瘤。利用直方图处理软件得到肿瘤IVIM(D、D*、f)的直方图参数。采用两独立样本t检验(正态分布)或Mann-WhitneyU检验(偏态分布)比较乳腺良、恶性病灶的IVIM直方图参数的差异。绘制ROC评价IVIM直方图参数独立和联合鉴别诊断乳腺良、恶性病变的效能,Z检验评价联合诊断ROC下面积(AUC)差异性。单变量及多变量二元logisti回归分析独立影响因素。结果乳腺恶性病变116个,良性病变42个。良、恶性病变D(90th、熵、峰度、均值、中位数、最小值、偏度)、f峰度、D*(90th、熵、峰度、均值、中位数、最大值、偏度)单因素分析有统计学意义。AUC最大为D偏度(0.818);敏感度最高为D熵(0.957);特异度最高为D偏度(0.857);准确度最高为D偏度(0.797)。D直方图联合诊断AUC、敏感度、特异度、准确度分别为0.903、0.948、0.786、0.88;f直方图联合诊断分别为0.604、0.672、0.548、0.73;D*直方图联合诊断为0.833、0.897、0.619、0.823;IVIM直方图联合诊断为0.953、0.982、0.833、0.924;IVIM直方图联合诊断AUC面积最大,与D值、f值、D*直方图分别联合诊断AUC差异有统计学意义。D熵(OR=2.943;P=0.037)及D中位数(OR=0.984;P=0.029)为乳腺恶性病变独立影响因素。结论乳腺磁共振IVIM直方图参数联合能显著提高判断乳腺良恶性病变诊断效能,D熵及D中位数为乳腺恶性病变独立影响因素。

关键词：乳腺病变体素内不相干运动成像联合诊断影响因素

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Integration of piezoelectric transducers(PZT and PVDF)within polymer-matrix composites for structural health monitoring applications:new success and challenges

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International Journal of Smart and Nano Materials 2020年第4期11卷 343-369页

作者： C.Tuloup W.Harizi Z.Aboura Y.meyer Roberval(Mechanics Energy and Electricity)Universitéde Technologie de CompiègneCNRSCentre de Recherche RoyallieuCompiègne CedexFrance Savoie SYMME Systems Laboratory Mechatronics and MaterialsUniversitéSavoie Mont-BlancChambéryFrance

This article investigates the interest of using in-situ piezoelectric(PZT and PVDF)disks to perform real-time Structural Health Monitoring(SHM)of glass fiber-reinforced polymer composites submitted to var-ious tensile *** goal is to evaluate the working range and SHM potential of such embedded transducers for relatively simple mechanical loadings,with the long-term aim of using them to monitor complete 3D structures submitted to more complex *** is performed acquiring the electrical capacitance variation of the embedded *** study the potential links between the insitu capacitance signal and the global response of the loaded host specimens,a multi-instrumentation composed of external Nondestructive Testing techniques was implemented on the surfaces of the specimens to search for multi-physical couplings between these external measurements and the capacitance *** confirmed the non-intrusiveness of the embedded transducers,and allowed estimating their working *** capacitance signal follows well the mechanical loadings,but the piezoceramic transducer gets damaged after a determined relatively low strain level due to its *** limits of this working domain are extended by using a stretchable PolyVinylidene Fluoride(PVDF)polymer transducer,allowing this one to perform in-situ and real-time SHM of its host tensile specimens until failure.

关键词： Polymer-matrix composites(PMCs) in-situ piezoelectric transducer structural health monitoring nondestructive testing tensile loading PZT PVDF

Optimization of phenol degradation by candida tropicalis Z-04 using Plackett-Burman design and response surface methodology

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Journal of Environmental Sciences 2011年第1期23卷 22-30页

作者： Jiangya Zhou Xiaojuan Yu Cong Ding Zhiping Wang Qianqian Zhou Hao pao Weimin ca School of Environmental Science and Engineering Shanghai Jiaotong University Dongchuan Road 800 Shanghai 200240 China.

Statistical experimental designs were used to optimize the process of phenol degradation by candida tropicalis Z-04, isolated from phenol-degrading aerobic granules. The most important factors influencing phenol degradation （p 〈 0.05）, as identified by a two-level Plackett-Burman design with 11 variables, were yeast extract, phenol, inoculum size, and temperature. Steepest ascent method was undertaken to determine the optimal regions of these four significant factors. Central composite design （CCD） and response surface analysis were adopted to further investigate the mutual interactions between these variables and to identify their optimal values that would generate maximum phenol degradation. The analysis results indicated that interactions between yeast extract and temperature, phenol and temperature, inocuhim size and temperature affected the response variable （phenol degradation） significantly. The predicted results showed that the maximum removal efficiency of phenol （99.10%） could be obtained under the optimum conditions of yeast extract 0.41 g/L, phenol 1.03 g/L, inoculum size 1.43% （V/V） and temperature 30.04℃. These predicted values were further verified by validation experiments. The excellent correlation between predicted and experimental values confirmed the validity and practicability of this statistical optimum strategy. This study indicated the excellent ability of C. tropicalis Z-04 in degrading high-strength phenol. Optimal conditions obtained in this experiment laid a solid foundation for further use of this microorganism in the treatment of highstrength phenol effluents.

关键词： phenol degradation candida tropicalis Z-04 optimization Plackett-Burman design response surface methodology

All-dielectric silicon metalens for two-dimensional particle manipulation in optical tweezers

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Photonics Research 2020年第9期8卷 1435-1440页

作者： TEANCHAI CHANTAKIT CHRISTIAN SCHLICKRIEDE BASUDEB SAIN FABIAN meyer THOMAS WEISS NATTAPORN CHATTHAM AND THOMAS ZENTGRAF Department of Physics Faculty of ScienceKasetsart UniversityBangkok 10900Thailand College of Advanced Manufacturing Innovation King Mongkut’s Institute of Technology LadkrabangBangkok 10520Thailand Department of Physics Paderborn UniversityWarburger Str.10033098 PaderbornGermany 4th Physics Institute and Research Center SCoPE University of StuttgartPfaffenwaldring 5770569 StuttgartGermany

Dynamic control of compact chip-scale contactless manipulation of particles for bioscience applications remains a challenging endeavor,which is restrained by the balance between trapping efficiency and scalable *** offer the implementation of feasible optical tweezers on a planar platform for shaping the exerted optical force by a microscale-integrated *** we design and experimentally demonstrate a highly efficient silicon-based metalens for two-dimensional optical trapping in the *** metalens concept is based on the pancharatnam–Berry phase,which enables the device for polarization-sensitive particle *** optical trapping setup is capable of adjusting the position of both the metasurface lens and the particle chamber freely in three directions,which offers great freedom for optical trap adjustment and ***-dimensional(2D)particle manipulation is done with a relatively low-numerical-aperture metalens(NA(ML)=0.6).We experimentally demonstrate both 2D polarization-sensitive drag and drop manipulation of polystyrene particles suspended in water and transfer of angular orbital momentum to these particles with a single tailored *** work may open new possibilities for lab-on-a-chip optical trapping for bioscience applications and microscale to nanoscale optical tweezers.

关键词： particle trapping dimensional

In situ grazing-incidence small-angle X-ray scattering observation of block-copolymer templated formation of magnetic nanodot arrays and their magnetic properties

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Nano Research 2017年第2期10卷 456-471页

作者： Andreas meyer Norbert Franz Hans Peter Oepen Jan Perlich Gerardina carbone Till Hartmut Metzger Institut fiJr Physikalische Chemie Universitat Hamburg Grindelallee 117 20146 Ham burg Germany Institut for Nanostruktur und Festkorperphysik Universitat Hamburg Jungiusstr. 11a 20355 Hamburg Germany HASYLAB/Deutsches Elektronen Synchrotron Notkestr. 85 22603 Hamburg Germany European Synchrotron Radiation Facility 6 rue Jules Horowitz 38043 Grenoble France

The fabrication of bit-patterned media （BPM） is crucial for new types of hard disk drives. The development of methods for the production of BPM is progressing rapidly. Conventional lithography reaches the limit regarding lateral resolution, and new routes are needed. In this study, we mainly focus on the dependence of the size and shape of magnetic nanodots on the Ar＋-ion etching duration, using silica dots as masks. Two-dimensional （2D） arrays of magnetic nanostructures are created using silica-filled diblock-copolymer micelles as templates. After the self-assembly of the micelles into 2D hexagonal arrays, the polymer shell is removed, and the SiO2 cores are utilized to transform the morphology into a （Co/Pt）2-multilayer via ion etching under normal incidence. The number of preparation steps is kept as low as possible to simplify the formation of the nanostructure arrays. High-resolution in situ grazing-incidence small-angle X-ray scattering （GISAXS） investigations are performed during the Ar＋-ion etching to monitor and control the fabrication process. The in situ investigation provides information on how the etching conditions can be improved for further ex situ experiments. The GISAXS patterns are compared with simulations. We observe that the dots change in shape from cylindrical to conical during the etching process. The magnetic behavior is studied by utilizing the magneto-optic Kerr effect. The Co/Pt dots exhibit different magnetic behaviors depending on their size, interparticle distance, and etching time. They show ferromagnetism with an easy axis of magnetization perpendicular to the film. A systematic dependence of the coercivitv on the dot size is observed.

关键词： poly(styrene)-b-poly(vinyl pyridine) argon ion etching self-assembly grazing-incidence small-angle X-ray scattering(GISAXS) simulation magnetic nanodot coercivity

Randomized clinical study of five days apostrophe therapy with mebendazole compared to quinacrine in the treatment of symptomatic giardiasis in children

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World Journal of Gastroenterology 2006年第39期12卷 6366-6370页

作者： Roberto caete Angel A Escobedo María E González Pedro Almirall Hygiene Epidemiology and Microbiology Centre Matanzas City Cuba Academic paediatric Hospital "Pedro Borrás" Havana City Cuba Institute of Gastro-enterology Havana City Cuba "Pedro Kourí" Institute Havana City Cuba

AIM： To compare the efficacy and safety of five days apostrophe therapy of mebendazole （MBZ） versus quinacrine （QC） on human giardiasis in children.METHODS： A clinical trial was carried out in paediatric patients （aged 5-15 years） with confirmed symptomatic G. duodenalis mono-infection. patients were randomly assigned to receive either MBZ [200 mg taken three times per day GRID）（n = 61）] or QC [2 mg/kg bodyweight tid （n = 61）], both for five days. Follow-up faecal samples were obtained at 3, 5 and 7 d after the end of the treatment.RESULTS： Although the frequency of cure was higher for QC （83.6%） than for MBZ （78.7%）, the difference was not statistically significant （P 〉 0.05）. Adverse events were reported more in the QC group （P 〈 0.05）, all of them transient and self-limiting.CONCLUSION： Despite final cure rates ocurring lower than expected, the overall results of this study reconfirmed the efficacy of MBZ in giardiasis and also indicate that, although comparable to QC, at least in this setting the 5 d course of MBZ did not appear to improve the cure rates in this intestinal parasitic infection.

关键词： Giardia infection/drug therapy Children Me- bendazole/therapeutic use Quinacrine/therapeutic use Benzimidazoles/therapeutic use Giardiasis/drug therapy Cuba

A New Perspective of the Physical Processes Associated with the Clear-Sky Greenhouse Effect over High Latitudes

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Advances in Atmospheric Sciences 2004年第2期21卷 171-180页

作者： Zuohao ca0 Ronald E．STEWART M．K．YAU MeteorologicalServiceofcanada，Ontario，canada DepartmentofAtmosphericandOceanicSciences，McGillUniversityMontreal，Quebec，canada

The physical processes associated with the clear-sky greenhouse effect in the presence of water vapor are examined by including surface emissivity in the greenhouse effect formulation, and by introducing a new way to partition physical processes of the greenhouse effect. In this new framework, it is found that the clear-sky greenhouse effect is governed by three physical processes associated with (1) the temperature contrast between the surface and the atmosphere, (2) the interaction between the surface emissivity and the temperature contrast, and (3) the surface emissivity. The importance of the three physical processes is assessed by computing their vertical and spectral variations far the subarctic winter and summer standard atmosphere using the radiation model MODTRAN3 (Moderate Resolution Transmittance code Version 3). The results show that the process associated with the temperature contrast between the surface and the atmosphere dominates over the other two processes in magnitude. The magnitude of this process has substantial variations in the spectral region of 1250 to 1880 cm-1 and in the far infrared region. Due to the low-level temperature inversion over the subarctic winter, there exists a negative contribution to the greenhouse trapping. The seasonal variations are, however, dominated by the processes associated with the interaction between the surface emissivity and the temperature contrast as well as the surface emissivity itself. The magnitudes of these two physical processes contributing to the greenhouse trapping over the subarctic winter are about 7 to 10 times of those over the subarctic summer, whereas the magnitude of the processes associated with the temperature contrast in the subarctic summer is only about 2 times of that in the subarctic winter.

关键词： greenhouse effect surface ernissivity physical processe high latitude seasonal variation

A Mathematical Model for Simultaneous Saccharification and Co-fermentation （SSCF） of C6 and C5 Sugars

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Chinese Journal of Chemical Engineering 2011年第2期19卷 185-191页

作者： Ricardo Morales-Rodriguez Krist V.Gernaey Anne S.meyer Gürkan Sin Computer Aided Process Engineering Center (caPEC) Department of Chemical and Biochemical EngineeringTechnical University of DenmarkDK-2800 LyngbyDenmark PROCESS Department of Chemical and Biochemical EngineeringTechnical University of DenmarkDK-2800 LyngbyDenmark BIOENG Department of Chemical and Biochemical EngineeringTechnical University of DenmarkDK-2800 LyngbyDenmark

Reliable production of biofuels and specifically bioethanol has attracted a significant amount of re-search *** this context,this study deals with dynamic simulation of bioethanol production processes and in particular aims at developing a mathematical model for describing simultaneous saccharification and co-fermentation （SSCF） of C6 and C5 *** model is constructed by combining existing mathematical mod-els for enzymatic hydrolysis and *** inhibition of ethanol on cellulose conversion is introduced in order to increase the *** mathematical model for the SSCF is verified by comparing the model predic-tions with experimental data obtained from the ethanol production based on kraft paper mill *** fitting the model to the data,only the yield coefficients for glucose and xylose metabolism were fine-tuned,which were found to be 0.43 g·g-1 （ethanol/glucose） and 0.35 g·g-1 （ethanol/xylose） *** promising validation results encourage further model application to evaluate different process configurations for lignocellulosic bioetha-nol technology.

关键词： bioethanol dynamic modeling simultaneous saccharification and co-fermentation