Theoretically predicted innovative palladium stripe dopingcobalt(111) surface with excellent catalytic performance for carbonmonoxide oxidative coupling to dimethyl oxalate

Pd-based catalysts are extensively employed to catalyze CO oxidative coupling to generate DMO,while the expensive price and high usage of Pd hinder its massive application in industrial production.Designing Pd-based catalysts with high efficiency and low Pd usage as well as expounding the catalytic mechanisms are significant for the reaction.In this study,we theoretically predict that Pd stripe doping Co(111)surface exhibits excellent performance than pure Pd(111),Pd monolayer supporting on Co(111)and Pd single atom doping Co(111)surface,and clearly expound the catalytic mechanisms through the density functional theory(DFT)calculation and micro-reaction kinetic model analysis.It is obtained that the favorable reaction pathway is COOCH_(3)-COOCH_(3)coupling pathway over these four catalysts,while the rate-controlling step is COOCH_(3)+CO+OCH_(3)→2COOCH_(3)on Pd stripe doping Co(111)surface,which is different from the case(2COOCH_(3)→DMO)on pure Pd(111),Pd monolayer supporting on Co(111)and Pd single atom doping Co(111)surface.This study can contribute a certain reference value for developing Pd-based catalysts with high efficiency and low Pd usage for CO oxidative coupling to DMO.

xStripeMerge:基于纠删码存储的高效宽条带生成方法

为了解决纠删码存储系统的已有宽条带生成方法中扩容方案将产生大量宽条带生成带宽,合并方案受限于双条带的问题,提出了一种针对多条带合并下的宽条带生成问题的高效宽条带生成方法。定义了多条带合并过程的2个关键算子,并将宽条带生成问题建模为组合优化问题,提出了优先寻找具有小的奇偶校验块传输成本的窄条带组合方案的高效宽条带生成方法xStripeMerge。实验结果表明,与目前最优的存储扩容方法相比,xStripeMerge可以减少75%宽条带生成带宽。xStripeMerge的时间和空间复杂度远优于扩展的双条带合并方法,xStripeMerge可以在更短的时间内获得与其性能相近的宽条带生成方案,并且xStripeMerge可以适用于大规模存储系统。

Agrobacterium tumefaciens-mediated transformation of rice with the spider insecticidal gene conferring resistance to leaffolder and striped stem borer

Immature embryos of rice varieties "Xiushui11" and "Chunjiang 11" precultured for 4d were infected and transformed by Agrobacterium tumefaciens strain EHA101/pExT7 (containing the spider insecticidal gene). The resistant cant were transferred onto the differentiation medium and plants were regenerated. The transformation frequency reached 56%-72% measured as numbers of Geneticin (G418)-resistant calli produced and 36%-60% measured as numbers of transgenic plants regenerated, respectively. PCR and Southern blot analysis of transgenic plants confirmed that the T-DNA had been integrated into the rice genome. Insect bioassays using T1 transgenic plants indicated that the mortality of the leaffolder (Cnaphalocrasis medinalis) after 7d of leaf feeding reached 38%-61% and the corrected mortality of the striped stem borer (Chilo suppressalis) after 7d of leaf feeding reached 16%-75%. The insect bioassay results demonstrated that the transgenic plants expressing the spider insecticidal protein conferred enhanced resistance to these pests.

Genetic Analysis and Molecular Mapping of Novel White Striped Leaf Mutant Gene in Rice

A new white striped leaf mutant wsll was discovered from Nipponbare mutated by ethyl methanesulfonate. The mutant showed white striped leaves at the seedling stage and the leaves gradually turned green after the tillering stage. The chlorophyll content of wsll was significantly lower than that of wild-type during the fourth leaf stage, tillering stage and booting stage. The numbers of chloroplast, grana and grana lamella were reduced and the thylakoids were degenerated in wsll compared with wild type. Genetic analysis showed that the wsll was controlled by a single recessive gene. Molecular mapping of the wsll was performed using an F2 population derived from wsll/Nanjing 11. The wsll was finally mapped on the telomere region of chromosome 9 and positioned between simple sequence repeat markers RM23742 and RM23759 which are separated by approximately 486.5 kb. The results may facilitate map-based cloning of wsll and understanding of the molecular mechanism of the regulation of leaf-color by WSL1 in rice.

The role of leptin in striped hamsters subjected to food restriction and refeeding

Food restriction （FR） and refeeding （Re） have been suggested to impair body mass regulation and thereby making it easier to regain the lost weight and develop over-weight when FR ends. However, it is unclear if this is the case in small mammals showing seasonal forging behaviors. In the present study, energy budget, body fat and serum leptin level were measured in striped hamsters that were exposed to FR-Re. The effects of leptin on food intake, body fat and genes expressions of several hypothalamus neuropeptides were determined. Body mass, fat content and serum leptin level decreased during FR and then increased during Re. Leptin supplement significantly attenuated the increase in food intake during Re, decreased genes expressions of neuropepetide Y （NPY） and agouti-related protein （AgRP） of hypothalamus and leptin of white adipose tissue （WAT）. Hormone-sensitive lipase （HSL） gene expression of WAT increased in leptin-treated hamsters that were fed ad libitum, but decreased in FR-Re hamsters. This indicates that the adaptive regulation of WAT HSL gene expression may be involved in the mobilization of fat storage during Re, which partly contributes to the resistance to FR-Re-induced overweight. Leptin may be involved in the down regulations of hypothalamus orexigenic peptides gene expression and consequently plays a crucial role in controlling food intake when FR ends.

Transgenic japonica rice expressing the cry1C gene is resistant to striped stem borers in Northeast China

Rice production and quality are seriously affected by the lepidopteran pest,striped stem borer(SSB),in Northeast China.In this study,a synthetic cry1 C gene encoding Bacillus thuringiensis(Bt)δ-endotoxin,which is toxic to lepidopteran pest,was transformed into a japonica rice variety(Jigeng 88)in Northeast China by Agrobacterium-mediated transformation.Through molecular detection and the Basta resistance germination assay,a total of 16 single-copy homozygous transgenic lines were obtained from 126 independent transformants expressing cry1 C.Finally,four cry1 C-transgenic lines(JL16,JL23,JL41,and JL42)were selected by evaluation of the Cry1 C protein level,insect-resistance and agronomic traits.The cry1 C-transgenic lines had higher resistance to SSB and higher yield compared with non-transgenic(NT)control plants.T-DNA flanking sequence analysis of the transgenic line JL42 showed that the cry1 C gene was inserted into the intergenic region of chromosome 11,indicating that its insertion may not interfere with the genes near insertion site.In summary,this study developed four cry1 C-transgenic japonica rice lines with high insect resistance and high yield.They can be used as insect-resistant germplasm materials to overcome the problem of rice yield reduction caused by SSB and reduce the use of pesticides in Northeast China.

Noise-induced striped trajectories of Rossler systems

In this paper, the generation of striped trajectories in phase space by noise-injection is considered. With suitable amplitudes of noise, the steady-state system orbits appear in rectangular striped shape. The relationship between the shape （including the range and the number of stripes） and some parameters is discussed. The result shows that noise can also generate the striped shape effectively and simply, which is similar to the newly-discovered striped pattern generated by controlled Rossler systems.

Fine mapping and transcriptome sequencing reveal candidate genes conferring all-stage resistance to stripe rust on chromosome arm 1AL in Chinese wheat landrace AS1676

Stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), threatens wheat production worldwide, and resistant varieties tend to become susceptible after a period of cultivation owing to the variation of pathogen races. In this study, a new resistance gene against Pst race CYR34 was identified and predicted using the descendants of a cross between AS1676, a highly resistant Chinese landrace, and Avocet S, a susceptible cultivar. From a heterozygous plant from a F7recombinant inbred line(RIL) population lacking the Yr18 gene, a near-isogenic line(NIL) population was developed to map the resistance gene. An allstage resistance gene, YrAS1676, was identified on chromosome arm 1AL via bulked-segregant exomecapture sequencing. By analyzing a large NIL population consisting of 6537 plants, the gene was further mapped to the marker interval between KA1A_485.36 and KA1A_490.13, spanning 485.36–490.13 Mb on1AL. A total of 66 annotated genes have been reported in this region. To characterize and predict the candidate gene(s), an RNA-seq was performed using NIL-R and NIL-S seedlings 3 days after CYR34 inoculation. Compared to NIL-S plants, NIL-R plants showed stronger immune reaction and higher expression levels of genes encoding pathogenesis-associated proteins. These differences may help to explain why NIL-R plants were more resistant to Pst race CYR34 than NIL-S plants. By combining fine-mapping and transcriptome sequencing, a calcium-dependent protein kinase gene was finally predicted as the potential candidate gene of YrAS1676. This gene contained a single-nucleotide polymorphism. The candidate gene was more highly expressed in NIL-R than in NIL-S plants. In field experiments with Pst challenge,the YrAS1676 genotype showed mitigation of disease damage and yield loss without adverse effects on tested agronomic traits. These results suggest that YrAS1676 has potential use in wheat stripe rust resistance breeding.

Transcriptome analysis reveals different response of resistant and susceptible rice varieties to rice stripe virus infection

Rice stripe disease,caused by rice stripe virus (RSV) which is transmitted by small brown planthopper (SBPH,Laodelphax striatellus Fallen),resulted in serious losses to rice production during the last 2 decades.Research on the molecular differences between resistant and susceptible rice varieties and the interaction between rice and RSV remains inadequate.In this study,RNA-Seq was used to analyze the transcriptomic differences between the resistant and susceptible rice varieties at different times post RSV infection.Through Gene Ontology (GO) annotation,the differentially expressed genes (DEGs) related to transcription factors,peroxidases,and kinases of 2 varieties at 3 time points were identified.Comparing these 2 varieties,the DEGs associated with these 3 GOs were numerically less in the resistant variety than in the susceptible variety,but the expression showed a significant up-or down-regulation trend under the conditions of|log_2(Fold change)|>0&P_(adj)<0.05 by significance analysis.Then through Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation,DEGs involved in some pathways that have a contribution to disease resistance including plant hormone signal transduction and plant–pathogen interaction were found.The results showed that resistance responses regulated by abscisic acid (ABA) and brassinosteroids (BR) were the same for 2 varieties,but that mediated by salicylic acid (SA) and jasmonic acid (JA)/ethylene (ET) were different.The DEGs in resistant and susceptible varieties at the 3 time points were identified in both PAMP-triggered immunity (PTI) and Effector proteintriggered immunity (ETI),with that most of the unigenes of the susceptible variety were involved in PTI,whereas most of the unigenes of the resistant variety were involved in ETI.These results revealed the different responses of resistant and susceptible varieties in the transcription level to RSV infection.

Removal of Stripes in Remote Sensing Images Based on Statistics Combined with Image Enhancement

A method to remove stripes from remote sensing images is proposed based on statistics and a new image enhancement method.The overall processing steps for improving the quality of remote sensing images are introduced to provide a general baseline.Due to the differences in satellite sensors when producing images,subtle but inherent stripes can appear at the stitching positions between the sensors.These stitchingstripes cannot be eliminated by conventional relative radiometric calibration.The inherent stitching stripes cause difficulties in downstream tasks such as the segmentation,classification and interpretation of remote sensing images.Therefore,a method to remove the stripes based on statistics and a new image enhancement approach are proposed in this paper.First,the inconsistency in grayscales around stripes is eliminated with the statistical method.Second,the pixels within stripes are weighted and averaged based on updated pixel values to enhance the uniformity of the overall image radiation quality.Finally,the details of the images are highlighted by a new image enhancement method,which makes the whole image clearer.Comprehensive experiments are performed,and the results indicate that the proposed method outperforms the baseline approach in terms of visual quality and radiation correction accuracy.

Reproductive Biology of the Striped Seabream Lithognathus mormyrus （Linnaeus, 1758） from AI-Haneah Fishing Site, Mediterranean Sea, Eastern Libya

Reproductive biology of L. mormyrus was studied using monthly samples totaling 224 fish obtained from AI-Haneah fishing site, eastern Libya Mediterranean Sea. Lengths of the examined fish ranged between 11.5 cm and 23.4 cm. Corresponding weights were 24.5 g and 160.8 g. The minimum values of the condition factors, KF and Kc, were 1.38 and 1.21 at the average fish length of 12.4 cm. These values increased with increases in length until they reached maximum values of 1.59 and 1.41 at the length of 22.1 cm. The high values of KF and Kc, Gonado-Somatic Index and oocyte diameter maintained during May, June, July, and August and the monthly changes in gonadal condition, indicated that summer was the breeding season of L. mormyrus. The oocyte diameter ranged between 379± 25.3 μ and 1,511 ± 143.3μ （n = 76） with an average of 895 ± 111.3 μ. The sex ratio was in favor of females during all months of the study. The overall sex ratio was 1 ： 1.52. Length at first maturity, Ls0, for L. mormyrus was found to be 14.15 cm for males and 14.45 for females. Overall average of absolute fecundity was 4,342±557 egg per fish （n = 45）. The overall average of relative fecundity was 234± 181 egg per cm. Absolute fecundity increased with increasing fish length.

Investigation of Aegilops umbellulata for stripe rust resistance,heading date,and the contents of iron,zinc,and gluten protein

Aegilops umbellulata(UU)is a wheat wild relative that has potential use in the genetic improvement of wheat.In this study,46 Ae.umbellulata accessions were investigated for stripe rust resistance,heading date(HD),and the contents of iron(Fe),zinc(Zn),and seed gluten proteins.Forty-two of the accessions were classified as resistant to stripe rust,while the other four accessions were classified as susceptible to stripe rust in four environments.The average HD of Ae.umbellulata was significantly longer than that of three common wheat cultivars(180.9 d vs.137.0 d),with the exception of PI226500(138.9 d).The Ae.umbellulata accessions also showed high variability in Fe(69.74-348.09 mg kg^(-1))and Zn(49.83-101.65 mg kg^(-1))contents.Three accessions(viz.,PI542362,PI542363,and PI554399)showed relatively higher Fe(230.96-348.09 mg kg^(-1))and Zn(92.46-101.65 mg kg^(-1))contents than the others.The Fe content of Ae.umbellulata was similar to those of Ae.comosa and Ae.markgrafii but higher than those of Ae.tauschii and common wheat.Aegilops umbellulata showed a higher Zn content than Ae.tauschii,Ae.comosa,and common wheat,but a lower content than Ae.markgrafii.Furthermore,Ae.umbellulata had the highest proportion of γ-gliadin among all the species investigated(Ae.umbellulata vs.other species=mean 72.11%vs.49.37%;range:55.33-86.99%vs.29.60-67.91%).These results demonstrated that Ae.umbellulata exhibits great diversity in the investigated traits,so it can provide a potential gene pool for the genetic improvement of these traits in wheat.

甘肃省小麦条锈病研究进展及机遇与挑战

小麦生产关乎国家粮食安全,条锈病是小麦生产上最重要的病害之一。甘肃陇南越夏区是小麦条锈病常发易变区和新小种策源地。通过系统回顾甘肃省农业科学院植物保护研究所立足陇南越夏区开展小麦条锈病研究60年来的进展,分析了存在的问题,并提出未来研究方向,旨在更好保持甘肃省农业科学院小麦条锈病研究在国内影响和地位,为持续引领甘肃省小麦条锈病研究提供借鉴和帮助。

基于时间序列植被指数的小麦条锈病抗性等级鉴定方法

条锈病严重影响小麦产量,培育抗条锈病的小麦品种至关重要。针对传统育种中抗性鉴定手段单一、效率低的问题,该研究提出了一种通过小麦冠层植被指数的时间序列实现对条锈病不同抗性等级的高效鉴定方法。该方法利用无人机采集自然发病的育种群体小麦(共600个样本,516个基因型)冠层多时相的光谱图像,使用随机蛙跳算法和ReliefF算法筛选出6个条锈病病害严重度的敏感特征:归一化色素叶绿素指数(normalized pigment chlorophyll index,NPCI)、沃尔贝克指数(woebbecke index,WI)、叶绿素红边指数(chlorophyll index rededge,CIrededge)、绿大气抵抗植被指数(green atmospherically resistant index,GARI)、归一化差分植被指数(normalized difference vi,NDVI)、叶绿素绿指数(chlorophyll index green,CIgreen),这些敏感特征在试验群体中的时间序列符合条锈病的发病规律,验证了其作为条锈病发病严重度敏感特征的有效性;基于支持向量机(support vector machine,SVM)算法使用上述敏感特征建立条锈病病害严重度等级分类模型,在测试集的表现中,与使用未经过筛选的原始特征所建立的模型相比在精度、平均准确率、平均召回率和F1分数上分别仅下降6.2%、3.3%、2.7%、4.0%,证明了所筛选敏感特征的有效性;针对一般机器学习算法难以捕捉不同抗性等级样本之间较小的特征变化差异的问题,提出了一种从植被指数时间序列转化生成的二维图像中提取特征实现条锈病抗性等级分类的方法。将敏感特征中能够较好区分不同抗病等级的4个时间序列植被指数(NPCI、GARI、NDVI、WI),通过格拉姆角场方法生成格拉姆角和场图像,并制作成数据集,使用DenseNet121网络进行训练,以实现不同条锈病抗病等级的分类。建立的条锈病抗性等级分类模型中,由NPCI时间序列图像建立的分类模型测试效果最佳,其准确率为0.837,召回率为0.834,F1分数可达0.833,能够较好地实现对群体小麦不同品种(系)的条锈病抗性等级差异的区分,表明基于光谱植被指数时间序列的小麦条锈病抗性等级识别方法可以用于小麦抗病育种中抗性等级的鉴定,并可为其他作物的病害抗性等级鉴定提供一定的参考。

引进美国小麦种质资源抗病性及品质性状鉴定

为了挖掘新的种质资源,本研究对引自美国的442份小麦材料对白粉病和条锈病的抗病性、蛋白含量以及高分子量麦谷蛋白(HMW-GS)亚基组成进行了鉴定分析。抗病性鉴定结果显示,153份材料抗白粉病,27份抗条锈病,6份兼抗两种病害。蛋白质含量达到GB/T 17892-1999《优质小麦强筋小麦》一等(粗蛋白质含量≥15.0%)的样品有143份。高分子量麦谷蛋白检测发现,供试材料共含18种HMW-GS亚基和100种不同亚基组合类型,其中N,7+9,5+10出现次数最多,优质亚基1、2*、7^(oe)、17+18、5+10的材料分别占总材料数的25.6%、5.2%、27.8%、7.7%和25.6%,含7^(oe),5+10亚基的有36份,含2*,5+10亚基的有1份,含2*,7^(oe)亚基的有7份。综合抗病性及品质分析结果显示,PI 17738等11份材料至少抗1种病害,且蛋白含量≥15.0%,湿面筋含量≥35.0%,同时含有稀有优质亚基。以上11份材料可作为我国优质、抗病小麦培育亲本,为我国小麦抗病和品质遗传改良提供优异基因源。

小麦条锈病抗性基因定位及分子标记技术研究进展

条锈病流行对小麦生产造成巨大损失,选育和种植持久抗性品种是防治小麦条锈病最经济有效的策略。为达到多基因聚合培育持久抗病品种的目标,必须不断发掘抗病种质、解析其抗病遗传机制并开发分子标记。基于文献,对条锈病抗性基因发掘涉及的抗病性、分子标记、基因定位方法和定位进展及其在育种中的应用进行了综述,明确了小麦条锈病基因定位涉及技术的现状、局限性及优势,从而为后续的条锈病抗性基因发掘、多基因聚合和持久抗性小麦品种的选育与生产布局提供技术指导,以降低西北麦区和小麦主产区条锈病流行的频率,进一步促进国家粮食安全。

Adult neurogenesis in the four-striped mice(Rhabdomys pumilio)

In this study, we investigated non-captive four-striped mice （Rhabdomys pumilio） for evidence that adult neurogenesis occurs in the adult brain of animal models in natural environment. Ki-67 （a marker for cell proliferation） and doublecortin （a marker for immature neurons） immunos-taining conifrmed that adult neurogenesis occurs in the active sites of subventricular zone of the lateral ventricle with the migratory stream to the olfactory bulb, and the subgranular zone of the dentate gyrus of the hippocampus. No Ki-67 proliferating cells were observed in the striatum substantia nigra, amygdala, cerebral cortex or dorsal vagal complex. Doublecortin-immunore-active cells were observed in the striatum, third ventricle, cerebral cortex, amygdala, olfactory bulb and along the rostral migratory stream but absent in the substantia nigra and dorsal vagal complex. The potential neurogenic sites in the four-striped mouse species could invariably lead to increased neural plasticity.

西瓜果实网条突变体的转录组分析

以条纹自交系西瓜(TD)和网条突变体西瓜(WT)为材料,通过分离群体的条纹性状比例探索西瓜的条性状遗传基础;以转录组测序及表达差异分析为基础,探索网条突变体西瓜在不同发育阶段的表达谱变化,筛选出条纹自交系与网条突变体西瓜之间表达差异显著的基因57个,主要富集于光合作用天线蛋白通路、生物碱生物合成通路、氨基酸代谢通路等7种代谢途径;通过加权基因共表达网络对核心基因的进一步分析,初步挖掘出部分网条突变体西瓜中有关生物胁迫抗性的基因变化情况,进一步筛选确定西瓜深绿条纹基因(ClGS,watermelon dark-green stripe)、类半胱氨酸蛋白酶抑制剂5编码基因、UDP-葡萄糖基转移酶编码基因、类长春碱合成酶编码基因、叶绿素a-b结合蛋白编码基因可能是决定西瓜网条果皮性状的核心基因;qRT-PCR验证结果表明,条纹自交系西瓜与网条突变体西瓜在基因表达上存在明显差异。本研究为西瓜不同果皮条纹育种提供了新的种质资源,也为阐明西瓜不同果皮条纹性状形成的分子调控机制提供了一定的理论依据。

甘肃陇南小麦品种抗条锈病鉴定与评价

为了解甘肃陇南小麦育成品种和后备品种对当前条锈菌流行小种的抗性水平,利用条锈菌流行小种CYR32、CYR33和CYR34对60份供试小麦品种分别进行苗期、成株期抗病性鉴定。结果表明,在所有供试品种中,对CYR32、CYR33和CYR34表现苗期抗病的品种分别有9、22和10份,表现成株期抗病的品种分别有35、38和30份。结合苗期和成株期鉴定结果,对CYR32、CYR33和CYR34表现苗期感病而成株期抗病的品种分别有28、22和24份,占46.7%、36.7%和40.0%;中梁14号和兰天37号对CYR32、CYR33和CYR34均表现全生育期抗性,占3.3%。甘肃陇南麦区小麦品种对当前条锈菌流行小种多表现为成株期抗性,筛选出部分具有全生育期或成株期抗性的品种,可作小麦育种的亲本资源加以利用。

基于条带池化与血管增强的眼底图像动静脉分类方法

视网膜血管动静脉管径比是定量分析糖尿病、高血压等慢性疾病的先决条件,是许多心血管疾病的重要风险指标。随着深度学习技术的发展,许多基于卷积神经网络的方法凭借其捕获高级语义的能力,在眼底图像动静脉分类方面取得了较大的进展。然而,这些方法大多是采用叠加局部卷积和池化操作方式,难以很好地应用于条带形状的眼底视网膜血管。在本研究中,为了更有效地提取条带形状的视网膜血管特征,引入条带池化来捕获空间像素远距离依赖关系,同时考虑到动静脉交错复杂的特性,结合空间金字塔池化并提出了一种全新的混合池化技术以扩大神经网络的感受野和学习上下文信息。另一方面,考虑到眼底图像中血管与非血管分布的比例极不平衡,引入了血管增强模块,利用血管分布信息和高斯核函数约束的血管边缘的信息作为权重校正动静脉特征抑制背景特征,进而解决血管与背景分布比例不平衡问题。在分别包含40、22、45张彩色眼底图像的3种国际公开数据集DRIVE、LES和HRF上的实验表明,所提算法的平衡精度(BACC)分别为0.955、0.946、0.967,表明本研究结合条带池化与血管增强的方法能够较好解决眼底图像中动静脉交错复杂和类别不平衡问题,实现对眼底视网膜动静脉的精确分类,具有较高的应用价值。