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Pesticide food safety standards as companions to tolerances and maximum residue limits 被引量:3
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作者 Carl K Winter Elizabeth A Jara 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第11期2358-2364,共7页
Allowable levels for pesticide residues in foods, known as tolerances in the US and as maximum residue limits (MRLs) in much of the world, are widely yet inappropriately perceived as levels of safety concern. A nove... Allowable levels for pesticide residues in foods, known as tolerances in the US and as maximum residue limits (MRLs) in much of the world, are widely yet inappropriately perceived as levels of safety concern. A novel approach to develop scientifically defensible levels of safety concern is presented and an example to determine acute and chronic pesticide food safety standard (PFSS) levels for the fungicide captan on strawberries is provided. Using this approach, the chronic PFSS level for captan on strawberries was determined to be 2 000 mg kg-1 and the acute PFSS level was determined to be 250 mg kg-1. Both levels are far above the existing tolerance and MRLs that commonly range from 3 to 20 mg kg-~, and provide evidence that captan residues detected at levels greater than the tolerance or MRLs are not of acute or chronic health concern even though they represent violative residues. The benefits of developing the PFSS approach to serve as a companion to existing tolerances/MRLs include a greater understanding concerning the health significance, if any, from exposure to violative pesticide residues. In addition, the PFSS approach can be universally applied to all potential pesticide residues on all food commodities, can be modified by specific jurisdictions to take into account differences in food consumption practices, and can help prioritize food residue monitoring by identifying the pesticide/commodity combinations of the greatest potential food safety concern and guiding development of field level analytical methods to detect pesticide residues on prioritized pesticide/commodity combinations. 展开更多
关键词 pesticide residues food safety tolerances maximum residue limits (MRLs) regulation reference dose CAPTAN STRAWBERRIES
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Effects of Dimensional Tolerances on the Friction Power Loss of Hydrodynamic Journal Bearing System 被引量:2
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作者 魏塬 陈照波 +1 位作者 焦映厚 徐武彬 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期266-271,共6页
According to the dimensional tolerances on hydrodynamic journal bearing system, a nonlinear oil film force model was established,and the Reynolds' equation was solved by adopting finite difference method. In order... According to the dimensional tolerances on hydrodynamic journal bearing system, a nonlinear oil film force model was established,and the Reynolds' equation was solved by adopting finite difference method. In order to fulfill different dimensional tolerances in the system,adopting 2kfactor design and using the eccentricity ratio corresponding to the stability critical curve,the effects of the friction power loss brought by the dimensional tolerances of the dynamic viscosity,bearing width,bearing diameter and journal diameter were analyzed. The effect on dynamic characteristics of the hydrodynamic journal bearing system was quantitatively analyzed,and the nonlinear dynamic analysis, modeling and calculation methods were studied while considering the manufacturing tolerances. The results show that in contrast to the impacts of the tolerances in journal diameter,dynamic viscosity and bearing width,the bearing diameter tolerance would lead to the rise in the power loss, and the dimensional tolerances have different degrees of impacts on the journal bearing system. The friction power loss decreased as the eccentricity ratio increased, and when the eccentricity ratio was 0. 695 the power loss came to the minimum.The investigation would find the best solution and reduce energy consumption,then control varieties of nonlinear dynamical behavior effectively,and provide a theoretical basis for hydrodynamic journal bearing system in parameter design. 展开更多
关键词 hydrodynamic journal bearing dimensional tolerances factor design friction power loss
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Robust Fault Diagnosis of Analog Circuits with Tolerances
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作者 Ying Deng1, Yigang He1 , Xu He2 ,Yichuang Sun3 1. College of Electrical and Information Engineering,Hunan University, 410082, Changsha, Hunan, China 2. Department of Computer Science, Hunan University, 410082, Changsha, Hunan, China 3. Department of Ele 《湖南大学学报(自然科学版)》 EI CAS CSCD 2000年第S2期133-138,共6页
A method for robust analog fault diagnosis using hybrid neural networks is proposed. The primary focus of the paper is to provide robust diagnosis using a mechanism to deal with the problem of element tolerances and r... A method for robust analog fault diagnosis using hybrid neural networks is proposed. The primary focus of the paper is to provide robust diagnosis using a mechanism to deal with the problem of element tolerances and reduce testing time. The proposed approach is based on the fault dictionary diagnosis method and backward propagation neural network (BPNN) and the adaptive resonance theory (ART) neural network. Simulation results show that the method is robust and fast for fault diagnosis of analog circuits with tolerances. 展开更多
关键词 ANALOG CIRCUITS FAULT diagnosis tolerances Artificial NEURAL networ|
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Extensive Taguchi's Quality Loss Function Based On Asymmetric tolerances
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作者 祝伟 李元生 刘锋 《Journal of China University of Mining and Technology》 2004年第2期252-254,共3页
If specification interval is asymmetric, basic specification is the target value of quality characteristics. In this paper Taguchi's quality loss function is applied to describe quality loss based on asymmetric to... If specification interval is asymmetric, basic specification is the target value of quality characteristics. In this paper Taguchi's quality loss function is applied to describe quality loss based on asymmetric tolerances. The measurement of quality loss which is caused by the deviation of quality characteristics from basic specification is further presented. 展开更多
关键词 basic SPECIFICATION ASYMMETRIC tolerances QUALITY LOSS
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Selection efficiencies for improving drought/salt tolerances and yield using introgression breeding in rice(Oryza sativa L.) 被引量:2
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作者 Ying Wang Lubiao Zhang +3 位作者 Afif Nafisah Linghua Zhu Jianlong Xu Zhikang Li 《The Crop Journal》 SCIE CAS 2013年第2期134-142,共9页
The backcross(BC) breeding strategy has been increasingly used for developing high yielding varieties with improved abiotic stress tolerances in rice. In this study, 189Huang-Hua-Zhan(HHZ) introgression lines(ILs) dev... The backcross(BC) breeding strategy has been increasingly used for developing high yielding varieties with improved abiotic stress tolerances in rice. In this study, 189Huang-Hua-Zhan(HHZ) introgression lines(ILs) developed from three different selection schemes were evaluated for yield related traits under drought stress and non-stress conditions in the target and off-season winter nursery environments to assess the selection efficiency of BC breeding for improving different complex traits, and led us to five important results. The first result indicated that the primary target traits should be selected first in the target environments(TEs) in order to achieve the maximum genetic gain. Secondly, BC breeding for drought tolerance(DT) in rice was almost equally effective by strong phenotypic selection in the main target environments and in the winter-season of Hainan.Thirdly, exploiting genetic diversity in the subspecific gene pools is of great importance for future genetic improvement of complex traits in rice. Fourthly, considerable genetic gain can be effectively achieved by selection for secondary target traits among the ILs with the primary traits. Finally, the developed ILs provide useful materials for future genetic/genomic dissection and molecular breeding of complex traits. 展开更多
关键词 BACKCROSS BREEDING High YIELD DROUGHT TOLERANCE Salt TOLERANCE SELECTION efficiency
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Production of Transgenic Tall Fescue Plants with Enhanced Stress Tolerances by Agrobacterium tumefaciens-Mediated Transformation 被引量:3
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作者 WU Guan-ting CHEN Jin-qing +5 位作者 HU Zhang-hua LANG Chun-xiu CHEN Xiao-yun WANG Fu-lin JIN Wei XIA Ying-wu 《Agricultural Sciences in China》 CAS CSCD 2006年第5期330-338,共9页
In order to improve stress tolerances of turf-type tall fescue (Festuca arundinacea Schreb.), Agrobacterium tumefaciens strain EHA105 carrying plasmid pCMD containing stress tolerance-related CBF1 gene from Arabidop... In order to improve stress tolerances of turf-type tall fescue (Festuca arundinacea Schreb.), Agrobacterium tumefaciens strain EHA105 carrying plasmid pCMD containing stress tolerance-related CBF1 gene from Arabidopsis thaliana was used to transform mature seeds-derived embryogenic calli of four cultivars. A total of 112 transgenic plants were regenerated from 32 independent lines and verified by histochemical detection of GUS activity, PCR assay and Southern hybridization analysis. The transformation frequency ranged from 0.92 to 2.87% with apparent differences among the cultivars. Stress tolerances of transgenic plants were enhanced, which was shown by the facts that transgenic plants had distinct growth superiority and significantly higher survival rate than non-transformed ones under high salinity and high osmosis stresses, and that relative electronic conductivity of in vitro leaves treated with low and high temoeratures, dehvdration and high salinity stresses was 25-30% lower in transgenic plants than in control plants.In addition,it was observed that growth of transgenic plants was inhibited due to constitutive overexpression of CBF1 gene under normal environmental conditions. 展开更多
关键词 tall fescue (Festuca arundinacea Schreb.) Agrobacterium tumefaciens genetic transformation CBF1 gene stress tolerance
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QTL underlying iron and zinc toxicity tolerances at seedling stage revealed by two sets of reciprocal introgression populations of rice(Oryza sativa L.) 被引量:1
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作者 Huan Liu Aijaz Soomro +6 位作者 Yajun Zhu Xianjin Qiu Kai Chen Tianqing Zheng Longwei Yang Danying Xing Jianlong Xu 《The Crop Journal》 SCIE CAS CSCD 2016年第4期280-289,共10页
Iron and zinc are two trace elements that are essential for rice. But they are toxic at higher concentrations, leading to severe rice yield losses especially in acid soils and inland valleys. In this study, two recipr... Iron and zinc are two trace elements that are essential for rice. But they are toxic at higher concentrations, leading to severe rice yield losses especially in acid soils and inland valleys. In this study, two reciprocal introgression line(IL) populations sharing the same parents were used with high-density SNP bin markers to identify QTL tolerant to iron and zinc toxicities. The results indicated that the japonica variety 02,428 had stronger tolerance to iron and zinc toxicities than the indica variety Minghui 63. Nine and ten QTL contributing to iron and zinc toxicity tolerances,respectively, were identified in the two IL populations. The favorable alleles of most QTL came from 02,428. Among them, q FRRDW2, q ZRRDW3, and q FRSDW11 appeared to be independent of genetic background. The region C11S49–C11S60 on chromosome 11 harbored QTL affecting multiple iron and zinc toxicity tolerance-related traits, indicating partial genetic overlap between the two toxicity tolerances. Our results provide essential information and materials for developing excellent rice cultivars with iron and/or zinc tolerance by marker-assisted selection(MAS). 展开更多
关键词 RICE Reciprocal INTROGRESSION lines IRON TOLERANCE Zinc TOLERANCE Quantitative trait locus/loci(QTL)
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Estimation of genetic parameters for upper thermal tolerances and growth-related traits in turbot Scophthalmus maximus 被引量:1
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作者 WANG Xin′an MA Aijun +4 位作者 HUANG Zhihui SUN Zhibin CUI Wenxiao QU Jiangbo YU Hong 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第5期1736-1745,共10页
An abnormally high temperature produces a stress response in turbot causing large economic losses in the turbot aquaculture industry of China. A genetic improvement of the upper thermal tolerance (UTT) of turbot could... An abnormally high temperature produces a stress response in turbot causing large economic losses in the turbot aquaculture industry of China. A genetic improvement of the upper thermal tolerance (UTT) of turbot could allow cultured fi sh to adapt. A genetic evaluation of UTT is required for determining the practicability of including this trait into a breeding program. In this study, data were recorded from a temperature tolerance test conducted on 3 200 individual turbots from 32 full-sib groups. A cross-sectional linear model and a cross-sectional threshold probit model were used to analyze the test-period survival and a cross-sectional threshold logit model was used to analyze the test-day survival. In addition, phenotypic and genetic correlations between body weight and survival data were estimated. The estimated heritability values obtained from the cross-sectional linear model (CSL), the cross-sectional threshold (probit) model (THRp), and the cross-sectional threshold (logit) model (THRl) were 0.247 9±0.108 3, 0.288 3±0.161 2, and 0.106 9±0.045 2, respectively. The correlation coeffi cients among the full-sib family estimated breeding values (EBVs) obtained from the three models were greater than 0.998 6 and all models produced an almost identical family ranking. The accuracies of selection obtained with the CSL, THRp, and THRl model were 0.773 8, 0.775 4, and 0.784 4, respectively, the greatest from the THRl model. The genetic correlations between body weight and survival data EBVs from the CSL, THRp, and THRl models were 0.020 1,-6.201 1×10^-4 , and -3.115 4×10^-4 , respectively, and the phenotypic correlations between the two traits were -0.837 1 and -0.667 1, respectively. The findings of this study provide background information to determine the best strategy of selection for the genetic improvement of UTT in turbot. 展开更多
关键词 Scophthalmus MAXIMUS UPPER thermal TOLERANCE genetic parameters CROSS-SECTIONAL models
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Quality Characteristics Distribution and Its Simulation Based on Asymmetric Tolerances 被引量:1
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作者 祝伟 李元生 《Journal of China University of Mining and Technology》 2003年第2期223-225,共3页
The application of normal distribution for quality characteristics has its limits on the condition that specification interval is asymmetric. In this paper, the compound normal distribution N(L,σ12,σ22) was proposed... The application of normal distribution for quality characteristics has its limits on the condition that specification interval is asymmetric. In this paper, the compound normal distribution N(L,σ12,σ22) was proposed and simulated, the property of the parameters Lσ1 and σ2 was studied. The distribution was further applied toangle quality process control. 展开更多
关键词 specification interval asymmetric tolerance quality characteristics SIMULATION
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Effect of Flaxseed on Bile Tolerances of <i>Lactobacillus acidophilus, Lactobacillus bulgaricus</i>, and <i>Streptococcus thermophilus</i> 被引量:1
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作者 Meghana Theegala René Adalberto Chigüila Arévalo +2 位作者 Valerie Viana Douglas Olson Kayanush Aryana 《Food and Nutrition Sciences》 2021年第7期670-680,共11页
Consu<span>mption of flaxseed provides health benefits. Bile tolerance allows </span>survival of probiotics in the intestinal tract. The objective was to determine whether or not flaxseed enhances bile tol... Consu<span>mption of flaxseed provides health benefits. Bile tolerance allows </span>survival of probiotics in the intestinal tract. The objective was to determine whether or not flaxseed enhances bile tolerance of </span><span style="font-family:""><i></span><i><span style="font-family:"">Lactobacillus acidophilus</span></i><span style="font-family:""> (<i>L. acidophilus</i></span><i><span style="font-family:""></i></span></i><span style="font-family:"">) LA-K<i>, </i></span><i><span style="font-family:""><i></span></i><i><span style="font-family:"">Lactobacillus delbruekii</span></i><i><span style="font-family:""></i></span></i><span style="font-family:""> ssp.<i> </i></span><i><span style="font-family:""><i></span></i><i><span style="font-family:"">bulgaricus </span></i><span style="font-family:"">(</span><i><span style="font-family:"">L. bulgaricus</span></i><i><span style="font-family:""></i></span></i><span style="font-family:"">) LB-12,<span> </span></span><span style="font-family:"">and </span><span style="font-family:""><i></span><i><span style="font-family:"">Streptococcus salivarius</span></i><i><span style="font-family:""></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:"">ssp.<i> </i></span><i><span style="font-family:""><i></span></i><i><span style="font-family:"">thermophilus </span></i><span style="font-family:"">(<i>S. </i></span><i><span style="font-family:"">thermophilus</span></i><i><span style="font-family:""></i></span></i><span style="font-family:"">) ST-M5</span><i><span style="font-family:"">. </span></i><span style="font-family:"">Control and experimental (62 g flaxseed/L) broths containing 0.3% oxgall were prepared for each culture, sterilized, cooled, inoculated, and plated for 8 h. <span>Growth of each microorganism in both the control and </span>experimental broths was evaluated by the slope of the regression line of its log count versus time after inoculation. Flaxseed significantly enhanced growth of </span><span style="font-family:""><i></span><i><span style="font-family:"">L.</span></i><i><span style="font-family:""> acidophilus</span></i><i><span style="font-family:""></i></span></i><span style="font-family:""> but not </span><span style="font-family:""><i></span><i><span style="font-family:"">L. </span></i><i><span style="font-family:"">bulgaricus</span></i><i><span style="font-family:""></i></span></i><span style="font-family:""> and </span><span style="font-family:""><i></span><i><span style="font-family:"">S. thermophilus</span></i><i><span style="font-family:""></i></span></i><span style="font-family:""> over 8 h compared to its corresponding control. Therefore, flaxseed improved the bile tolerance of </span><span style="font-family:""><i></span><i><span style="font-family:"">L. acidophilus</span></i><i><span style="font-family:""></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:"">but not of </span><span style="font-family:""><i></span><i><span style="font-family:"">S. thermophilus</span></i><i><span style="font-family:""></i></span></i><span style="font-family:""> and </span><span style="font-family:""><i></span><i><span style="font-family:"">L. bulgaricus</span></i><i><span style="font-family:""></i></span></i><span style="font-family:"">. 展开更多
关键词 FLAXSEED Bile tolerance Lactobacillus acidophilus Lactobacillus bulgaricus Streptococcus thermophilus Probiotic
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Robustness Criteria for Concurrent Evaluation of the Impact of Tolerances in Multiobjective Electric Machine Design Optimization
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作者 Gerd Bramerdorfer 《CES Transactions on Electrical Machines and Systems》 CSCD 2020年第1期3-12,共10页
This article is about a comparison of different measures for determining the robustness or reliability of electric machine designs in the presence of inevitable tolerances.The selected criteria shall be suitable for c... This article is about a comparison of different measures for determining the robustness or reliability of electric machine designs in the presence of inevitable tolerances.The selected criteria shall be suitable for concurrent evaluation in the course of solving state-of-the-art large scale multi-objective opti-mization problems.In the past,besides particularly customized criteria,mainly gradient based measures,worst case information,or standard deviation based quantities were considered.In this work,the quantile measure is introduced for electric machine design optimization and compared with the existing solutions.The evaluation of a design’s robustness is typically examined based on finite element simulations.As for most measures a signif-icant number of parameter combinations and thus computations are required,a surrogate model assisted approach is presented to minimize computational effort and runtime.A test problem is defined and analyzed to illustrate the differences of selected robustness measures.Results reveal the importance of considering robustness in the optimization process.Moreover,a careful choice of appropriate measures has to be taken.Selected designs are compared and conclusions and an outlook on future activities are presented. 展开更多
关键词 electric machine optimization ROBUSTNESS sen-sitivity six sigma tolerance analysis QUANTILE
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Determination of the High Temperature Stress Tolerances of Bread Wheat Genotypes
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作者 Zahit Kaylhan Korkut Alpay Balkan +1 位作者 Ismet Baser Oguz Bilgin 《Journal of Life Sciences》 2017年第7期346-354,共9页
Thirty bread wheat genotypes were used as material during the 2014-2015 cropping season. The experimental layout was a randomized complete block design with 3 replications. The sowing rate was 500 seeds square meter. ... Thirty bread wheat genotypes were used as material during the 2014-2015 cropping season. The experimental layout was a randomized complete block design with 3 replications. The sowing rate was 500 seeds square meter. Sowing was done in plots of 6 rows (1.2 m × 5 m, spaced 20 cm apart) in Namlk Kemal University, Faculty of Agriculture, Field Crops Department experimental area. Two sowing times were performed. First sowing was made in November suggested usual (standard) and second one was made in January as delayed sown in order to push growing stages of plants into periods in which heat stress is expected will be effected. Sowing times were allotted to main-plots while genotypes were allotted to sub-plots. When the bread wheat varieties and lines used in the experiment are evaluated in terms of tolerance to high temperature, it was shown that Dropia and Nota varieties and CIMMYT-HTN 2014/15-2, CIMMYT-HTN 2014/15 -6, CIMMYT-HTN 2014/15 - 10 lines were better tolerance to high temperature. However, it was noticed that these genotypes were not included in the first groups in terms of grain yield. It is possible to utilize these genotypes as a genitor in cross-breeding programs for breeding studies for tolerance to high temperatures. 展开更多
关键词 Heat tolerance bread wheat advanced lines heat sensitive
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An Environment‑Tolerant Ion‑Conducting Double‑Network Composite Hydrogel for High‑Performance Flexible Electronic Devices 被引量:2
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作者 Wenchao Zhao Haifeng Zhou +3 位作者 Wenkang Li Manlin Chen Min Zhou Long Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期352-369,共18页
High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic devices.However,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use i... High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic devices.However,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use in soft electronics.To resolve these issues,a method involving freeze–thawing and ionizing radiation technology is reported herein for synthesizing a novel double-network(DN)ICH based on a poly(ionic liquid)/MXene/poly(vinyl alcohol)(PMP DN ICH)system.The well-designed ICH exhibits outstanding ionic conductivity(63.89 mS cm^(-1) at 25℃),excellent temperature resistance(-60–80℃),prolonged stability(30 d at ambient temperature),high oxidation resist-ance,remarkable antibacterial activity,decent mechanical performance,and adhesion.Additionally,the ICH performs effectively in a flexible wireless strain sensor,thermal sensor,all-solid-state supercapacitor,and single-electrode triboelectric nanogenerator,thereby highlighting its viability in constructing soft electronic devices.The highly integrated gel structure endows these flexible electronic devices with stable,reliable signal output performance.In particular,the all-solid-state supercapacitor containing the PMP DN ICH electrolyte exhibits a high areal specific capacitance of 253.38 mF cm^(-2)(current density,1 mA cm^(-2))and excellent environmental adaptability.This study paves the way for the design and fabrication of high-performance mul-tifunctional/flexible ICHs for wearable sensing,energy-storage,and energy-harvesting applications. 展开更多
关键词 Ionic liquids Double-network hydrogels Temperature tolerance Multifunctionality Flexible electronic devices
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MIR1868 negatively regulates rice cold tolerance at both the seedling and booting stages 被引量:1
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作者 Yang Shen Xiaoxi Cai +7 位作者 Yan Wang Wanhong Li Dongpeng Li Hao Wu Weifeng Dong Bowei Jia Mingzhe Sun Xiaoli Sun 《The Crop Journal》 SCIE CSCD 2024年第2期375-383,共9页
Low temperature causes rice yield losses of up to 30%–40%,therefore increasing its cold tolerance is a breeding target.Few genes in rice are reported to confer cold tolerance at both the vegetative and reproductive s... Low temperature causes rice yield losses of up to 30%–40%,therefore increasing its cold tolerance is a breeding target.Few genes in rice are reported to confer cold tolerance at both the vegetative and reproductive stages.This study revealed a rice-specific 24-nt miRNA,miR1868,whose accumulation was suppressed by cold stress.Knockdown of MIR1868 increased seedling survival,pollen fertility,seed setting,and grain yield under cold stress,whereas its overexpression conferred the opposite phenotype.Knockdown of MIR1868 increased reactive oxygen species(ROS)scavenging and soluble sugar content under cold stress by increasing the expression of peroxidase genes and sugar metabolism genes,and its overexpression produced the opposite effect.Thus,MIR1868 negatively regulated rice cold tolerance via ROS scavenging and sugar accumulation. 展开更多
关键词 RICE Cold tolerance MIRNA ROS scavenging Soluble sugar accumulation
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Compositional and Hollow Engineering of Silicon Carbide/Carbon Microspheres as High-Performance Microwave Absorbing Materials with Good Environmental Tolerance 被引量:1
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作者 Lixue Gai Yahui Wang +5 位作者 Pan Wan Shuping Yu Yongzheng Chen Xijiang Han Ping Xu Yunchen Du 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期128-146,共19页
Microwave absorbing materials(MAMs)characterized by high absorption efficiency and good environmental tolerance are highly desirable in practical applications.Both silicon carbide and carbon are considered as stable M... Microwave absorbing materials(MAMs)characterized by high absorption efficiency and good environmental tolerance are highly desirable in practical applications.Both silicon carbide and carbon are considered as stable MAMs under some rigorous conditions,while their composites still fail to produce satisfactory microwave absorption performance regardless of the improvements as compared with the individuals.Herein,we have successfully implemented compositional and structural engineering to fabricate hollow Si C/C microspheres with controllable composition.The simultaneous modulation on dielectric properties and impedance matching can be easily achieved as the change in the composition of these composites.The formation of hollow structure not only favors lightweight feature,but also generates considerable contribution to microwave attenuation capacity.With the synergistic effect of composition and structure,the optimized SiC/C composite exhibits excellent performance,whose the strongest reflection loss intensity and broadest effective absorption reach-60.8 dB and 5.1 GHz,respectively,and its microwave absorption properties are actually superior to those of most SiC/C composites in previous studies.In addition,the stability tests of microwave absorption capacity after exposure to harsh conditions and Radar Cross Section simulation data demonstrate that hollow SiC/C microspheres from compositional and structural optimization have a bright prospect in practical applications. 展开更多
关键词 SiC/C composites Compositional engineering Hollow engineering Microwave absorption Environmental tolerance
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Abiotic stress treatment reveals expansin like A gene OfEXLA1 improving salt and drought tolerance of Osmanthus fragrans by responding to abscisic acid 被引量:1
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作者 Bin Dong Qianqian Wang +7 位作者 Dan Zhou Yiguang Wang Yunfeng Miao Shiwei Zhong Qiu Fang Liyuan Yang Zhen Xiao Hongbo Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期573-585,共13页
Sweet osmanthus(Osmanthus fragrans) is a having general approval aromatic tree in China that is widely applied to landscaping and gardening. However, the evergreen tree adaptability is limited by many environmental st... Sweet osmanthus(Osmanthus fragrans) is a having general approval aromatic tree in China that is widely applied to landscaping and gardening. However, the evergreen tree adaptability is limited by many environmental stresses. Currently, limited information is available regarding the genetic analysis and functional identification of expansin genes in response to abiotic stress in sweet osmanthus. In this study, a total of 29 expansin genes were identified and divided into four groups by genome-wide analysis from the sweet osmanthus genome. Transcriptome and quantitative Real-time PCR analysis showed that the cell wall-localized protein expansin-like A(OfEXLA1) gene was significantly induced by salt and drought treatment. Histochemical GUS staining of transgenic Arabidopsis lines in which GUS activity was driven with the OfEXLA1 promoter, GUS activity was significantly induced by salt, drought, and exogenous abscisic acid(ABA). In yeast, we found OfEXLA1overexpression significantly improved the population of cells compared with wild-type strains after NaCl and polyethylene glycol(PEG)treatment. Additionally, OfEXLA1 overexpression not only promoted plant growth, but also improved the salt and drought tolerance in Arabidopsis. To gain insight into the role of ABA signaling in the regulation of OfEXLA1 improving abiotic tolerance in sweet osmanthus, four differentially expressed ABA Insensitive 5(ABI5)-like genes(OfABL4, OfABL5, OfABL7, and OfABL8) were identified from transcriptome, and dualluciferase(dual-LUC) and yeast one hybrid(Y1H) assay showed that OfABL4 and OfABL5 might bind to OfEXLA1 promoter to accumulate the OfEXLA1 expression by responding to ABA signaling to improve abiotic tolerance in sweet osmanthus. These results provide the information for understanding the molecular functions of expansin-like A gene and molecular breeding of sweet osmanthus in future. 展开更多
关键词 Osmanthus fragrans Abiotic tolerance EXPANSIN Abscisic acid
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A Data Intrusion Tolerance Model Based on an Improved Evolutionary Game Theory for the Energy Internet 被引量:1
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作者 Song Deng Yiming Yuan 《Computers, Materials & Continua》 SCIE EI 2024年第6期3679-3697,共19页
Malicious attacks against data are unavoidable in the interconnected,open and shared Energy Internet(EI),Intrusion tolerant techniques are critical to the data security of EI.Existing intrusion tolerant techniques suf... Malicious attacks against data are unavoidable in the interconnected,open and shared Energy Internet(EI),Intrusion tolerant techniques are critical to the data security of EI.Existing intrusion tolerant techniques suffered from problems such as low adaptability,policy lag,and difficulty in determining the degree of tolerance.To address these issues,we propose a novel adaptive intrusion tolerance model based on game theory that enjoys two-fold ideas:(1)it constructs an improved replica of the intrusion tolerance model of the dynamic equation evolution game to induce incentive weights;and (2)it combines a tournament competition model with incentive weights to obtain optimal strategies for each stage of the game process.Extensive experiments are conducted in the IEEE 39-bus system,whose results demonstrate the feasibility of the incentive weights,confirm the proposed strategy strengthens the system’s ability to tolerate aggression,and improves the dynamic adaptability and response efficiency of the aggression-tolerant system in the case of limited resources. 展开更多
关键词 Energy Internet Intrusion tolerance game theory racial competition adaptive intrusion response
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Boosting oxygen reduction activity and CO_(2) resistance on bismuth ferrite-based perovskite cathode for low-temperature solid oxide fuel cells below 600℃ 被引量:1
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作者 Juntao Gao Zhiyun Wei +5 位作者 Mengke Yuan Zhe Wang Zhe Lü Qiang Li Lingling Xu Bo Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期600-609,I0013,共11页
Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)... Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)FeO_(3-δ) perovskites as highly-active catalysts for LT-SOFCs.Sm doping can significantly enhance the electrocata lytic activity and chemical stability of cathode.At 600℃,Bi_(0.675)Sm_(0.025)Sr_(0.3)FeO_(3-δ)(BSSF25) cathode has been found to be the optimum composition with a polarization resistance of 0.098 Ω cm^2,which is only around 22.8% of Bi_(0.7)Sr_(0.3)FeO_(3-δ)(BSF).A full cell utilizing BSSF25 displays an exceptional output density of 790 mW cm^(-2),which can operate continuously over100 h without obvious degradation.The remarkable electrochemical performance observed can be attributed to the improved O_(2) transport kinetics,superior surface oxygen adsorption capacity,as well as O_(2)p band centers in close proximity to the Fermi level.Moreover,larger average bonding energy(ABE) and the presence of highly acidic Bi,Sm,and Fe ions restrict the adsorption of CO_(2) on the cathode surface,resulting in excellent CO_(2) resistivity.This work provides valuable guidance for systematic design of efficient and durable catalysts for LT-SOFCs. 展开更多
关键词 Low-temperature solid oxide fuel cell Perovskite cathode DFT calculations CO_(2) tolerance
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Gastric cancer liver metastasis will reduce the efficacy of immunotherapy 被引量:1
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作者 Liang Wang Shan-Shan Liu +6 位作者 Sheng-Mei Zhang Xiao-Qian Chen Tao Huang Rong Tian Ya-Qi Zhao Zhou Chen Cai-Rang Xianba 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期2760-2764,共5页
Immune checkpoint inhibitors augment the antitumor activity of T cells by inhibiting the negative regulatory pathway of T cells,leading to notable efficacy in patients with non-small cell lung cancer,melanoma,and othe... Immune checkpoint inhibitors augment the antitumor activity of T cells by inhibiting the negative regulatory pathway of T cells,leading to notable efficacy in patients with non-small cell lung cancer,melanoma,and other malignancies through immunotherapy utilization.However,secondary malignant liver tumors not only lower the liver's sensitivity to immunotherapy but also trigger systemic immune suppression,resulting in reduced overall effectiveness of immune therapy.Patients receiving immunotherapy for non-small cell lung cancer and melanoma experience reduced response rates,progression-free survival,and overall survival when secondary malignant tumors develop in the liver.Through Liu's retrospective analysis,valuable insights are provided for the future clinical management of these patients.Therefore,in patients with gastric cancer(GC),the occurrence of liver metastasis might be indicative of reduced efficacy of immuno-therapy.Overcoming liver immune tolerance mechanisms and their negative impacts allows for the potential benefits of immunotherapy in patients with GC and liver metastasis.INTRODUCTION Gastric cancer(GC)ranks among the prevalent malignancies affecting the digestive system globally.Based on the latest epidemiological data[1,2],it holds the fifth position for incidence and the fourth position for mortality among all malignant tumors.GC cases and fatalities in China make up roughly half of the worldwide figures.Earlier investigations[3]have demonstrated that the median overall survival(mOS)among advanced GC patients left untreated typically ranges from 3 to 4 months.Systemic chemotherapy recipients often experience a mOS of around one year,accompanied by a marked improvement in the quality of life among patients with advanced GC.The mainstay of treatment for advanced GC patients involves chemotherapeutic medications such as fluoropyrimidines,platinum compounds,and taxanes.However,their efficacy in tumor control is constrained by acquired resistance and primary resistance.The rise of personalized precision therapy has propelled immunotherapy into the spotlight as a crucial component of comprehensive treatment[4].By blocking the negative regulatory pathways of T cells,immune checkpoint inhibitors(ICIs)boost the anti-tumor effect of T cells.Immunotherapy has brought about significant therapeutic benefits for patients diagnosed with non-small cell lung cancer,melanoma,and related illnesses[5,6],instilling newfound hope in those with advanced GC[7].However,phase III clinical trial data[8-12]reveals that the incorporation of immunotherapy into chemotherapy regimens improves overall survival(OS)outcomes for patients with advanced GC.The liver's immune-exempt nature renders it less responsive to immunotherapy when secondary malignant tumors are present,fostering systemic immune suppression and yielding unfavorable outcomes in immune therapy[13-15].In retrospective research[16-20]pertaining to non-small cell lung cancer and melanoma,it has been observed that the presence of secondary liver malignancies may lower the response rate,progression-free survival(PFS),and OS rates in patients treated with immunotherapy,independent of factors such as tumor mutation burden and PD-L1 expression.Despite this,there is a paucity of studies examining whether the existence of secondary malignant liver tumors affects the effectiveness of immunotherapy in patients diagnosed with advanced HER-2 negative GC. 展开更多
关键词 Immune checkpoint inhibitors Gastric cancer Gastric cancer with liver metastasis IMMUNOTHERAPY Liver immune tolerance
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Influence of substrate process tolerances on transmission characteristics of frequency-selective surface 被引量:7
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作者 张鹤 卢俊 +1 位作者 孙贯成 肖洪亮 《Chinese Optics Letters》 SCIE EI CAS CSCD 2008年第1期54-56,共3页
Frequency-selective surface (FSS) is a two-dimensional periodic structure consisting of a dielectric substrate and the metal units (or apertures) arranged periodically on it. When manufacturing the substrate, its ... Frequency-selective surface (FSS) is a two-dimensional periodic structure consisting of a dielectric substrate and the metal units (or apertures) arranged periodically on it. When manufacturing the substrate, its thickness and dielectric constant suffer process tolerances. This may induce the center frequency of the FSS to shift, and consequently influence its characteristics. In this paper, a bandpass FSS structure is designed. The units are the Jerusalem crosses arranged squarely. The mode-matching technique is used for simulation. The influence of the tolerances of the substrate's thickness and dielectric constant on the center frequency is analyzed. Results show that the tolerances of thickness and dielectric constant have different influences on the center frequency of the FSS. It is necessary to ensure the process tolerance of the dielectric constant in the design and manufacturing of the substrate in order to stabilize the center frequency. 展开更多
关键词 FSS Influence of substrate process tolerances on transmission characteristics of frequency-selective surface
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