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浙江大学学报（农业与生命科学版） 2000年第2期26卷 125-126页

作者：周伟军 HAGberG per 浙江大学农业与生物技术学院浙江杭州310029 Nilsson-Ehle Laboratory

Techniques for microspore culture of Brassica napus have been improved rapidly, and embryogenesis has been achieved in a wide range of genotypes. Plants regenerated from microspore-derived embryoids can be haploid, diploid or polyploid. From rapeseed microspore culture it is reported that 70%-90% of regenerated plants are haploid. The usual methods of chromosome doubling involve soaking roots (most common) or whole plants in a colchicine solution, or culturing plantlets in colchicine-containing medium in the greenhouse. Other alternatives are injecting colchicine into the secondary buds or applying colchicine-soaked cotton plugs to axillary buds.

关键词：油菜小孢子秋水仙素纯合两倍体植株频率

Highly insulating thermoplastic blends comprising a styrenic copolymer for direct‐current power cable insulation

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High Voltage 2022年第2期7卷 251-259页

作者： Yingwei Ouyang Amir Masoud Pourrahimi IdaÖstergren Marcus Mellqvist JakobÅnevall Azadeh Soroudi Anja Lund Xiangdong Xu Thomas Gkourmpis per‐Ola Hagstrand Christian Müller Department of Chemistry and Chemical Engineering Chalmers University of TechnologyGöteborgSweden Department of Electrical Engineering Chalmers University of TechnologyGöteborgSweden Innovation&Technology Borealis ABStenungsundSweden

The impact of the composition of blends comprising low‐density polyethylene(LDPE),isotactic polypropylene(PP)and a styrenic copolymer additive on the thermomechanical properties as well as the direct‐current(DC)electrical and thermal conductivity is *** presence of 5 weight percent(wt%)of the styrenic copolymer strongly reduces the amount of PP that is needed to enhance the storage modulus above the melting temperature of LDPE from 40 to 24 wt%.At the same time,the copolymer improves the consistency of the thermomechanical properties of the resulting ternary *** both the DC electrical and thermal conductivity strongly decrease with PP content,the addition of the styrenic copolymer appears to have little influence on either ***,PP in combination with small amounts of a styrenic copolymer not only allows to reinforce LDPE at elevated temperatures but also functions as an electrical conductivity‐reducing additive,which makes such thermoplastic ternary formulations possible candidates for the insulation of high‐voltage power cables.

关键词： property. blends copolymer

Theoretical and Experimental Quantification of Solar radiation through a Tracking System

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Open Journal of Applied Sciences 2024年第9期14卷 2648-2660页

作者： Guy Christian Tubreoumya Eloi Salmwendé Tiendrebeogo Tchardja Combary Téré Dabilgou Jacques Nebié Boubou Bagré Alfa Oumar Dissa Antoine bere Laboratoire de Physique et de Chimie de lEnvironnement (LPCE) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso LAboratoire de Mathmatiques et PhySique (LA.M.P.S) Universit de Perpignan Via Domitia (UPVD) Perpignan France

This work deals with the estimation of solar radiation through a solar tracker aimed at evaluating the effect of solar tracking on the solar deposit in Burkina Faso. Using a two-axis solar tracking system, we experimentally measured solar radiation at our Joseph KI-ZErBO University site and compared it with that obtained by a numerical simulation run using Fortran programming software based on a mathematical model by Brichambaut. The results obtained from the mathematical and experimental studies show that, with a solar tracker, on a clear-sky day, solar irradiation is between 800 W·m−2 and 1000 W·m−2 between about 8 a.m. and 4 p.m., i.e. a duration of 8 hours of insolation. Analysis of the numerical and experimental results shows very good quantitative and qualitative agreement, with an average relative error of 18%.

关键词： Tracking System Solar radiation Dual Axis Energy Efficiency

Human Eosinophil Cell Manipulation by Optical Tweezers

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Open Journal of Biophysics 2024年第3期14卷 330-338页

作者： Pavel Yale Jean Michel Edoukoua Konin Abadê Ange-Boris N’guessan Michel Abaka Kouacou Jérémie T. Zoueu Laboratoire dInstrumentation Image et Spectroscopie (L2IS) Institut National Polytechnique Houphout-Boigny (INPHB) Yamoussoukro Cte dIvoire Laboratoire de Chimie et de Physique Appliques Sciences et Techniques Universit Alassane Ouattara Bouak Cte dIvoire

In this work, lateral deformation of human eosinophil cell during the lateral indentation by an optically trapped microbead of diameter 4.5 µm is studied. The images were captured using a CCD camera and the Boltzmann statistics method was used for force calibration. Using the Hertz model, we calculated and compared the elastic moduli resulting from the lateral force, showing that the differences are important and the force should be considered. Besides the lateral component, the setup also allows us to examine the lateral cell-bead interaction. The mean values of the properties obtained, in particular the elastic stiffness and the shear stiffness, were Eh = (37.76 ± 2.85) µN/m and Gh = (12.57 ± 0.32) µN/m. These results show that the lateral indentation can therefore be used as a routine method for cell study, because it enabled us to manipulate the cell without contact with the laser.

关键词： Optical Tweezers Human Eosinophil Cell Indentation Shear Stiffness

Conventional, but not remote ischemic preconditioning, reduces iNOS transcription in liver ischemia/reperfusion

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World Journal of Gastroenterology 2014年第28期20卷 9506-9512页

作者： bergthor Bjornsson Anders Winbladh Linda Bojmar Tommy Sundqvist per Gullstrand per Sandstrom Department of Surgery County Council of Ostergotland58185 Linkoping Sweden Department of Clinical and Experimental Medicine Faculty of Health SciencesLinkping University58185 Linkoping Sweden

AIM:To study the effects of preconditioning on inducible nitric oxide synthase(iNOS)and interleukin 1(IL-1)receptor transcription in rat liver ischemia/reperfusion injury(IrI).MetHODS:Seventy-two male rats were randomized into 3 groups:the one-hour segmental ischemia(IrI,n=24)group,the ischemic preconditioning(IPC,n=24)group or the remote ischemic preconditioning(rIPC,n=24)*** IPC and r-IPC were performed as 10 min of ischemia and 10 min of *** iNOS and the IL-1 receptor mrNA in the liver tissue was analyzed with real time *** total Nitrite and Nitrate(NOx)in continuously sampled microdialysate(MD)from the liver was *** addition,the NOx levels in the serum were ***:After 4 h of reperfusion,the iNOS mrNA was significantly higher in the r-IPC(ΔCt:3.44±0.57)group than in the IPC(ΔCt:5.86±0.82)group(P=0.025).The IL-1 receptor transcription activity was reduced in the IPC group(ΔCt:1.88±0.53 to 4.81±0.21),but not in the r-IPC group,during reperfusion(P=0.027).In the MD,a significant drop in the NOx levels was noted in the r-IPC group(12.3±2.2 to 4.7±1.2μmol/L)at the end of ischemia compared with the levels in early ischemia(P=0.008).A similar trend was observed in the IPC group(11.8±2.1 to 6.4±1.5μmol/L),although this difference was not statistically *** levels of NOx rose quickly during reperfusion in both ***:IPC,but not r-IPC,reduces iNOS and IL-1 receptor transcription during early reperfusion,indicating a lower inflammatory *** is consumed in the ischemic liver lobe.

关键词： Ischemia-reperfusion injury Preconditioning remote preconditioning Liver ischemia Liver surgery Microdialysis Nitric oxide Inducible nitric oxide synthase Interleukin-1 receptor

Prevalence and Spatial Distribution of Badnavirus in the Banana (Musa spp) Major Growing Areas in Burkina Faso

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American Journal of Plant Sciences 2023年第4期14卷 427-447页

作者： Bakary Ouattara Drissa Sérémé Moustapha Koala Léon Wêndé-m’minèré Nitiéma Kadidia Koïta Emmanuel Kaboré Issa Wonni Laboratoire de Protection et Défense des Cultures Institut de l’Environnement et de Recherches Agricoles Centre National de Recherche Scientifique et Technologique Ouagadougou Burkina Faso Laboratoire de Biosciences Département de Biologie et Physiologie Végétale Université Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire Central d’horticulture Institut de l’Environnement et de Recherches Agricoles Centre National de Recherche Scientifique et Technologique Bobo Dioulasso Burkina Faso

Banana streak virus (BSV) and Sugarcane bacilliform virus (SCBV) are two badnaviruses commonly found in all banana growing areas of the world. It is a threat to the production and improvement of Musa germplasm. In Burkina Faso, the presence of badnaviruses was reported in banana producing regions. The objective of this study was to determine the prevalence of BSV and SCBV in banana production areas of Burkina Faso. A survey followed by a symptomatologic study was conducted in banana plantations in 27 localities of the nine main banana producing regions from July to October 2018 and September to December 2020. In all, 251 leaf samples were collected and analysed for BSV and SCBV infection by Indirect Antigen Coated Plate Assay-ELISA followed by amplification of the rT/rNase H region using Polymerase chain reaction with Badna FP/rP and SCBV F/r primers, respectively. A variety of symptoms were observed on almost all plant organs which were revealed due to BSV by symptomatologic study. The results of serological and molecular diagnosis revealed a high overall prevalence of BSV in 80.48% of the samples tested. BSV was distributed in seven survey regions out of nine with prevalence ranging from 10% to 100% in North, Centre, Centre West, Hauts Bassins, Cascades, Centre East and Boucle of Mouhoun regions. Very low prevalence was recorded for SCBV in Cascades and East Centre region with 4.35 and 12.5%, respectively. Species detection using specific primers to each species revealed three main species: Banana streak Obino l’ewaï virus (BSOLV), Goldfinger virus (BSGFV) and Imové virus (BSIMV) in the samples tested, respectively in the proportions of 23%, 8% and 0.8%. Co-infection between BSV species was also detected.

关键词： Banana Streak Virus Sugarcane Bacilliform Virus Indirect Antigen Coated Plate Assay Polymerase Chain reaction Musa spp

Simulations and Experiments on A Solar-Assisted Heat Pump Water Heater-Comparisons between r290 and r22

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Simulations and Experiments on A Solar-Assisted Heat Pump Wa...

作者： per Kjellsen 上海交通大学

学位级别：硕士

As a larger share of the world population is gaining a higher living standard and a higher energy consumption,it is increasingly important to find new,better,and more efficienct ways to meet our energy demands.A solar-assisted heat pump water heater is one way to efficiently use solar energy to produce hot water for dometic *** are currently few commercial applications of this technology and it has remained an idea since it was first porposed in *** assisted heat pump can achive elevated evaporator temperature compared to a air-source heat pump and be more efficient when solar radiation is *** also has the advatage of using a refrigerant as fluid and not water and problemes related to frost is *** thesis presents a the results from an experiment conducted on a Solar-Assisted Heat Pump Water Heater using r22 as working ***,a simulation model was built that could load the weather data from experiment and perform a simulation using a refrigerant of *** refrigerant data was loaded from the NIST refprop database into a SIMULINK/Matlab *** this thesis,the simulation compared r22 and r290 as *** overall COP for the experiment was 3.39 under overcast conditions and 3.29 under sunny *** simulation predicted a COP of 4.69 and 4.47 for r290 and r22,respectively,under sunny *** simulation model was not validated and it is believed that the refrigerant charge of r22 was too low during *** is proposed to better and more targeted research of SAHPs by having a test rig where different key components can easily be changed and it is easy to evaluate *** it is suggested to research SAHP specify operation conditions for SAHPs and how to make it possible for SAHPs to outperform other heating *** should also be developed with natural refrigerants in mind.

关键词：建筑物能源消耗量节能设计

realization of High Efficient Ferroelectric perovskite Nanoparticles in Biopolymer-Matrix Solar Cells under Low Lighting

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Journal of Modern Physics 2023年第7期14卷 1019-1033页

作者： rémi ndioukane Fanta Baldé ndéye Coumba Yandé Fall Abdoul Kadri Diallo Diouma Kobor Jeanne Solard Laurence Motte Laboratoire de Chimie et de Physique des Matériaux (LCPM) University Assane Seck of Ziguinchor Ziguinchor Senegal Centrale de Proximité en Nanotechnologies de Paris Nord Institut Universitaire de Technologie de Villetaneuse Paris France Laboratory for Vascular Translational Science (LVTS) University Paris 13 Paris France

The idea to use ferroelectric materials (PZN-PT) came from the fact that the ferroelectric nature could facilitate electric charges accumulation on the interfaces of the solar cell. Thus, it would increase the open circuit voltage Voc which could reach more than 10 V. This would directly impact the efficiency which is proportional to Voc, thus hoping to obtain solar efficiency never equaled by the halide perovskites which are less stable and less resistant in aggressive environments. In this work, the solar cells produced gave an exceptional record efficiency of 39.32% with a very high open circuit voltage (Voc) of 3.50 V, a short-circuit current density (Jsc) of 0.118 mA/cm2 and an FF of 0.72 measured in the positive polarization direction under 3825 lux (5.6 W/m2) lighting. The negative polarization direction under 4781 lux (7 W/m2) lightning gave a current density of 2 mA/cm2, an open circuit voltage of 2.30 V and an FF of 0.35.

关键词： perovskite Nanoparticles Thin Film Ferrophotovoltaic Solar Cell

Developmental-behavioral pediatrics : evidence and practice

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