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The point of no return and pectoral angle of Japanese anchovy(Engraulis japonicus) larvae during growth and starvation

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Acta Oceanologica Sinica 2007年第5期26卷 144-152页

作者： WAN Ruijing LI Xiansen ZHUANG Zhimeng JOHANNESSEN Arne Key Laboratory of Ministry of Agriculture for Sustainable utilization of Marine Fishery Resources Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 266071 China department of Biology University of Bergen Bergen Norway

At a temperature of 23.0 - 24.8℃, the mixed feeding of Japanese anchovy larvae was initiated 24 h before the yolk-sac was exhausted. The point of no return （PNR） was reached on the 6th day after hatching. On the 4th day after hatching, the pectoral angle appeared in both fed and unfed anchovy larvae although it was more evident and sharper in the starved and the PNR stage larvae than in the fed ones. According to observations of larvae collected in the sea, the pectoral angles were evident not only in the larvae of 3.62 - 7.44 mm in standard length, but also in the larvae of 2.70 mm in standard length with remnants of yolk. The pectoral angles became diffuse when the larvae reached 7.84 mm and vanished at 9.86 mm. The pectoral angle cannot be used as a criterion to distinguish healthy from starving larvae.

关键词： Engraulis japonicus larvae starvation point of no return (PNR) pectoral angle

Microstructure characteristics of 12Cr ferritic/martensitic steels with various yttrium

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Journal of Rare Earths 2019年第5期37卷 547-554页

作者： Yingxue Chen Feifei Zhang Qingzhi Yan Xiaoxin Zhang Zhiyuan Hong Institute of Nuclear Materials School of Materials Science and Engineering University of Science and Technology Beijing department of reactor Engineering and Safety research Center China Nuclear Power Technology Research Institute Advanced Energy research Center Shenzhen University Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Optoelectronic Engineering Shenzhen University

12Cr ferritic/martensitic steels with 0, 0.1 wt%, 0.2 wt% and 0.3 wt% theoretical yttrium(Y) additions were fabricated by vacuum inducting melting and casting method. Solubilities of Y in the 12Cr steels are0.027, 0.078 and 0.17 for 12Cr-0.1 Y, 12Cr-0.2 Y and 12Cr-0.3 Y, respectively. Phase transformations and microstructure characteristics under different heat-treatment schedules were investigated. The starting temperature of ferrite-to-austenite transformation A^(c1) are maintained about 850℃, but the finishing temperature of ferrite-to-austenite transformation A^(c3) are about 950, 970, 980 and 1000℃ for 12Cr-0 Y,12Cr-0.1 Y, 12Cr-0.2 Y and 12Cr-0.3 Y, respectively, which indicates that A^(c3) increases gradually with the addition of Y. Martensite accompanied with a few δ-ferrite is the dominant structure in all the steels. The amount of δ-ferrite shows a strong dependence with the Y content and austenitizing temperature. Area fraction of δ-ferrite increases with the content of Y, which is the ferrite favouring element. The minimum amount of δ-ferrite are achieved at 950℃ for 12Cr-0 Y, 12Cr-0.1 Y, 12Cr-0.2 Y and 1000℃ for 12Cr-0.3 ***, more carbides precipitate along the martensite laths and grain boundaries in the Y-bearing steel due to the redistribution of carbon between austenite and ferrite resulting from the ferrite favouring element of Y.

关键词： 12Cr ferritic/martensitic steel Yttrium Casting Phase transformation Microstructure characteristics Rare earths

Characteristics of Atmospheric Pressure Rotating Gliding Arc Plasmas

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Plasma Science and Technology 2016年第5期18卷 473-477页

作者：张浩朱凤森屠昕薄拯岑可法李晓东 State Key Laboratory of Clean Energy utilization College of Energy Engineering Zhejiang University department of Electrical Engineering and Electronics University of Liverpool

In this work, a novel direct current （DC） atmospheric pressure rotating gliding arc （RGA） plasma reactor has been developed for plasma-assisted chemical reactions. The influence of the gas composition and the gas flow rate on the arc dynamic behaviour and the formation of reactive species in the N2 and air gliding arc plasmas has been investigated by means of electrical signals, high speed photography, and optical emission spectroscopic diagnostics. Compared to conventional gliding arc reactors with knife-shaped electrodes which generally require a high flow rate （e.g., 10-20 L/min） to maintain a long arc length and reasonable plasma discharge zone, in this RGA system, a lower gas flow rate （e.g., 2 L/min） can also generate a larger effective plasma reaction zone with a longer arc length for chemical reactions. Two different motion patterns can be clearly observed in the N2 and air RGA plasmas. The time-resolved arc voltage signals show that three different arc dynamic modes, the arc restrike mode, takeover mode, and combined modes, can be clearly identified in the RGA plasmas. The occurrence of different motion and arc dynamic modes is strongly dependent on the composition of the working gas and gas flow rate.

关键词： rotating gliding arc (RGA) gas flow rate optical emission spectroscopy motion behavior electrical characteristics

Efficient iron plaque formation on tea(Camellia sinensis) roots contributes to acidic stress tolerance

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Journal of Integrative Plant Biology 2019年第2期61卷 155-167页

作者： Xianchen Zhang Honghong Wu Lingmu Chen Yeyun Li Xiaochun Wan State Key Laboratory of Tea Plant Biology and utilization Anhui Agricultural University department of Botany and Plant Sciences University of California

Tea plants grow in acidic soil, but to date, their intrinsic mechanisms of acidic stress tolerance have not been elucidated. Here, we assessed the tea plant response to growth on NHt4 nutrient media having different p H and iron levels. When grown in standard NHt4 nutrient solution(iron insufficient, 0.35 mg Là1 Fe2t), tea roots exhibited significantly lower nitrogen accumulation, plasma membrane Ht-ATPase activity, and protein levels; net Htefflux was lower at pH 4.0 and 5.0 than at pH 6.0. Addition of30 mg Là1 Fe2t(iron sufficient, mimicking normal soil Fe2tconcentrations) to the NHt4 nutrient solution led to more efficient iron plaque formation on roots and increased root plasma membrane Ht-ATPase levels and activities at p H 4.0 eland 5.0, compared to the p H 6.0 condition. Furthermore,plants grown at pH 4.0 and 5.0, with sufficient iron,exhibited significantly higher nitrogen accumulation than those grown at pH 6.0. Together, these results support the hypothesis that efficient iron plaque formation, on tea roots, is important for acidic stress tolerance. Furthermore,our findings establish that efficient iron plaque formation is linked to increased levels and activities of the tea root plasma membrane Ht-ATPase, under low pH conditions.

关键词： ATPase PM Efficient iron plaque formation on tea Figure Fe

Population genomic analysis reveals key genetic variations and the driving force for embryonic callus induction capability in maize

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Journal of Integrative Agriculture 2024年第7期23卷 2178-2195页

作者： Peng Liu Langlang Ma Siyi Jian Yao He Guangsheng Yuan Fei Ge Zhong Chen Chaoying Zou Guangtang Pan Thomas Lübberstedt Yaou Shen State Key Laboratory of Crop Gene Exploration and utilization in Southwest China/Maize research Institute Sichuan Agricultural UniversityChengdu 611130China department of Agronomy Iowa State UniversityAmesIA 50011USA

Genetic transformation has been an effective technology for improving the agronomic traits of ***,it is highly reliant on the use of embryonic callus(EC)and shows a serious genotype *** this study,we performed genomic sequencing for 80 core maize germplasms and constructed a high-density genomic variation map using our newly developed pipeline(MQ2Gpipe).Based on the induction rate of EC(REC),these inbred lines were categorized into three *** low-REC germplasms displayed more abundant genetic diversity than the high-REC *** integrating a genome-wide selective signature screen and region-based association analysis,we revealed 95.23 Mb of selective regions and 43 REC-associated *** variants had phenotypic variance explained values ranging between 21.46 and 49.46%.In total,103 candidate genes were identified within the linkage disequilibrium regions of these REC-associated *** genes mainly participate in regulation of the cell cycle,regulation of cytokinesis,and other functions,among which MYB15 and EMB2745 were located within the previously reported QTL for EC *** leaf area-associated variants with large effects were closely linked to several REC-related loci,implying a potential synergistic selection of REC and leaf size during modern maize breeding.

关键词： maize genetic transformation embryonic callus selective signal association analysis

Features on Very Peripheral Collisions of 16O-Em at 3.7A GeV

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Chinese Physics Letters 2018年第3期35卷 14-17页

作者： M.S.El-Nagdy A.Abdelsalam B.M.Badawy P.I.Zarubin A.M.Abdalla A.Saber Physics department Faculty of ScienceHelwan UniversityHelwanEgypt Physics department Faculty of ScienceCairo UniversityGizaEgypt reactor Physics department Atomic Energy AuthorityEgypt Joint Institute for Nuclear research DubnaMoscowRussia department of Mathematical and Physical Engineering Faculty of Engineering in ShoubraBenha UniversityCairoEgypt

From 1540 inelastic interactions of 3. 7A GeV 160 projectile with emulsion nuclei, we select samples of 87 and 61 events carefully due to interactions of neutron （n） and singly charged particles （Z = 1）, respectively. New results concerning the topology of such events are investigated. The average multiplicities of secondary relativistic particles that appear as shower tracks for n and Z = 1 stay more or less constant when compared with analogous data on p-Em at similar energy. The multiplicity distributions and the average values of the various secondary charged particles are studied and compared with the corresponding predictions by the cascade evaporation model. The results assume that the n or Z = 1 from 16O collide peripherally with an emulsion target and are considered as an expansion to the N-N collisions.

关键词： Features on Very Peripheral Collisions of O-Em at 3.7 A GeV

Accurate design of spatially separated double active site in Bi_(4)NbO_(8)Cl single crystal to promote Z-Scheme photocatalytic overall water splitting

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Journal of Energy Chemistry 2023年第12期87卷 568-582,I0014页

作者： Kailong Gao Hongxia Guo Yanan Hu Hongbin He Mowen Li Xiaoming Gao Feng Fu Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Yanneng-Yanda Comprehensive Energy Industry Technology research Institute Shaanxi Modern Industrial College of Green and Efficient Utilization of Energy ResourcesShaanxi Collaborative Innovation Center of Clean Utilization of Low Rank CoalShaanxi Key Laboratory of Chemical Reaction EngineeringDepartment of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000ShaanxiChina

The efficiency of photocatalytic overall water splitting was mainly limited by the slow reaction kinetics of water *** to design effective surface active site to overcome the slow water oxidation reaction was a major ***,we propose a strategy to accelerate surface water oxidation through the fabrication spatially separated double active ***/Bi_(4)NbO_(8)Cl-OVs photocatalyst with spatially separated double active site was prepared by hydrogen reduction photoanode deposition *** to the high matching of the spatial loading positions of FeCoPi and OVs with the photogenerated charge distribution of Bi_(4)NbO_(8)Cl and corresponding reaction mechanisms of substrate,the FeCoPi and OVs on the(001)and(010)crystal planes of Bi_(4)NbO_(8)Cl photocatalyst provided surface active site for water oxidation reaction and electron shuttle reaction(Fe^(3+)/Fe^(2+)),*** visible light irradiation,the evolution O_(2)rate of FeCoPi/Bi_(4)NbO_(8)Cl OVs was 16.8μmol h^(-1),as 32.9 times as Bi_(4)NbO_(8)***,a hydrogen evolution co-catalyst PtRu@Cr_(2)O_(3)was prepared by sequential photodeposition *** to the introduction of Ru,the Schottky barrier between PbTiO_(3)and Pt was effectively reduced,which promoted the transfer of photogenerated electrons to PtRu@Cr_(2)O_(3)thermodynamically,the evolution H_(2)rate on PtRu@Cr_(2)O_(3)/PbTiO_(3)increased to 664.8 *** based of the synchronous enhancement of the water oxidation performance on FeCoPi/Bi_(4)NbO_(8)Cl-OVs and water reduction performance on PtRu@Cr_(2)O_(3)/PbTiO_(3),a novel Z-Scheme photocatalytic overall water splitting system(FeCoPi/Bi_(4)NbO_(8)Cl-OVs)mediated by Fe^(3+)/Fe^(2+)had successfully *** visible light irradiation,the evolution rates of H_(2)and O_(2)were 2.5 and 1.3μmol h^(-1),*** work can provide some reference for the design of active site and the controllable synthesis of OVs spatial *** the other hand,the hydr

关键词： Spatially separated double active sites FeCoPi/Bi_(4)NbO_(8)Cl-OVs Photocatalytic water oxidation Photocatalytic hydrogen evolution Hydrogen evolution co-catalyst PtRu@Cr_(2)O_(3) Z-Scheme photocatalytic overall water splitting system

Maintenance of mesophyll potassium and regulation of plasma membrane H^+-ATPase are associated with physiological responses of tea plants to drought and subsequent rehydration

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The Crop Journal 2018年第6期6卷 611-620页

作者： Xianchen Zhang Honghong Wu Linmu Chen Linlin Liu Xiaochun Wan State Key Laboratory of Tea Plant Biology and utilization Anhui Agricultural University department of Botany and Plant Sciences University of California

Drought stress is one of the main factors limiting yield in tea plants. The plant cell's ability to preserve K^+homeostasis is an important strategy for coping with drought stress. Plasma membrane H^+-ATPase in the mesophyll cell is important for maintaining membrane potential to regulate K^+transmembrane transport. However, no research to date has investigated the possible relationship between plasma membrane H^+-ATPase and mesophyll K^+retention in tea plants under drought and subsequent rehydration conditions. In our experiment, drought stress inhibited plasma membrane H^+-ATPase activities and induced net H^+influx, leading to membrane potential depolarization and inducing a massive K^+efflux in tea plant mesophyll cells. Subsequent rehydration increased plasma membrane H^+-ATPase activity and induced net H^+efflux, leading to membrane potential hyperpolarization and thus lowering K^+loss. A first downregulated and then upregulated plasma membrane H^+-ATPase protein expression level was also observed under drought and subsequent rehydration treatment, a finding in agreement with the change of measured plasma membrane H^+-ATPase activities. Taken together, our results suggest that maintenance of mesophyll K^+in tea plants under drought and rehydration is associated with regulation of plasma membrane H^+-ATPase activity.

关键词： Drought stress H^+-ATPase Membrane potential Potassium Rehydration

Plant lncRNAs are enriched in and move systemically through the phloem in response to phosphate deficiency

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Journal of Integrative Plant Biology 2019年第4期61卷 492-508页

作者： Zhaoliang Zhang Yi Zheng Byung-Kook Ham Shupei Zhang Zhangjun Fei William J.Lucas State Key Laboratory of Tea Biology and utilization Anhui Agricultural University Boyce Thompson Institute for Plant research Cornell University Global Institute for Food Security Department of Biology University of Saskatchewan department of Plant Biology College of Biological Sciences University of California

In response to phosphate(Pi) deficiency, it has been shown that micro-RNAs(miRNAs) and mRNAs are transported through the phloem for delivery to sink tissues. Growing evidence also indicates that long noncoding RNAs(lncRNAs) are critical regulators of Pi homeostasis in plants. However, whether lncRNAs are present in and move through the phloem, in response to Pi deficiency, remains to be established. Here, using cucumber as a model plant, we show that lncRNAs are enriched in the phloem translocation stream and respond,systemically, to an imposed Pi-stress. A well-known lncRNA, IPS1, the target mimic(TM) of miRNA399,accumulates to a high level in the phloem, but is not responsive to early Pi deficiency. An additional 24 miRNA TMs were also detected in the phloem translocation stream; among them miRNA171 TMs and miR166 TMs were induced in response to an imposed Pi *** studies identified 22 lncRNAs which move systemically into developing leaves and root tips. A CU-rich PTB motif was further identified in these mobile lncRNAs. Our findings revealed that lncRNAs respond to Pi deficiency, non-cell-autonomously, and may act as systemic signaling agents to coordinate early Pi deficiency signaling, at the whole-plant level.

关键词： Plant lncRNAs enriched phloem phosphate deficiency