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Regulation effects of water and nitrogen on yield,water,and nitrogen use efficiency of wolfberry

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Journal of Arid Land 2024年第1期16卷 29-45页

作者： GAO Yalin QI Guangping MA Yanlin YIN Minhua WANG Jinghai WANG Chen TIAN Rongrong XIAO Feng LU Qiang WANG Jianjun College of Water Conservancy and Hydropower Engineering Gansu Agricultural UniversityLanzhou 730070China Jingtaichuan Electric Power Irrigation Water Resource Utilization Center in gansu Province Baiyin 730900China

Wolfberry(Lycium barbarum L.)is important for health care and ecological ***,it faces problems of low productivity and resource utilization during *** reasonable models for water and nitrogen management is important for solving these *** on field trials in 2021 and 2022,this study analyzed the effects of controlling soil water and nitrogen application levels on wolfberry height,stem diameter,crown width,yield,and water(WUE)and nitrogen use efficiency(NUE).The upper and lower limits of soil water were controlled by the percentage of soil water content to field water capacity(θ_(f)),and four water levels,i.e.,adequate irrigation(W0,75%-85%θ_(f)),mild water deficit(W1,65%-75%θ_(f)),moderate water deficit(W2,55%-65%θ_(f)),and severe water deficit(W3,45%-55%θ_(f))were used,and three nitrogen application levels,i.e.,no nitrogen(N0,0 kg/hm^(2)),low nitrogen(N1,150 kg/hm^(2)),medium nitrogen(N2,300 kg/hm^(2)),and high nitrogen(N3,450 kg/hm^(2))were *** results showed that irrigation and nitrogen application significantly affected plant height,stem diameter,and crown width of wolfberry at different growth stages(P<0.01),and their maximum values were observed in W1N2,W0N2,and W1N3 *** weight per plant and yield of wolfberry first increased and then decreased with increasing nitrogen application under the same water *** weight per hundred grains and dry weight percentage increased with increasing nitrogen application under W0 ***,under other water treatments,the values first increased and then decreased with increasing nitrogen *** and its component of wolfberry first increased and then decreased as water deficit increased under the same nitrogen *** water use efficiency(IWUE,8.46 kg/(hm^(2)·mm)),WUE(6.83 kg/(hm^(2)·mm)),partial factor productivity of nitrogen(PFPN,2.56 kg/kg),and NUE(14.29 kg/kg)reached their highest values in W2N2,W1N2,W1N2,and W1N1 treatments.R

关键词： water deficit growth characteristics yield water and nitrogen use efficiency principal component analysis

Adaptive Graph Convolutional Adjacency Matrix Network for Video Summarization

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Computers, Materials & Continua 2024年第8期80卷 1947-1965页

作者： Jing Zhang Guangli Wu Shanshan Song School of Cyberspace Security Gansu University of Political Science and LawLanzhou730000China

Video summarization aims to select key frames or key shots to create summaries for fast retrieval,compression,and efficient browsing of *** neural networks efficiently capture information about graph nodes and their neighbors,but ignore the dynamic dependencies between *** address this challenge,we propose an innovative Adaptive Graph Convolutional Adjacency Matrix Network(TAMGCN),leveraging the attention mechanism to dynamically adjust dependencies between graph ***,we first segment shots and extract features of each frame,then compute the representative features of each ***,we utilize the attention mechanism to dynamically adjust the adjacency matrix of the graph convolutional network to better capture the dynamic dependencies between graph ***,we fuse temporal features extracted by Bi-directional Long Short-Term Memory network with structural features extracted by the graph convolutional network to generate high-quality *** experiments are conducted on two benchmark datasets,TVSum and SumMe,yielding F1-scores of 60.8%and 53.2%,*** results demonstrate that our method outperforms most state-of-the-art video summarization techniques.

关键词： Attention mechanism deep learning graph neural network key-shot video summarization

Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions

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Journal of Integrative Agriculture 2024年第1期23卷 122-140页

作者： Jingui Wei Qiang Chai Wen Yin Hong Fan Yao Guo Falong Hu Zhilong Fan QimingWang State Key Laboratory of Aridland Crop Science Lanzhou 730070China College of Agronomy Gansu Agricultural UniversityLanzhou 730070China College of Life Sciences Northwest Normal UniversityLanzhou 730070China

The development of modern agriculture requires the reduction of water and chemical N fertilizer *** the planting density can maintain higher yields,but also consumes more of these restrictive ***,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains *** study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern china in 2020 to *** treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N *** water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme *** with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improv

关键词： water and N reduction plant density maize grain yield N uptake compensation effect

Modelling analysis embodies drastic transition among global potential natural vegetations in face of changing climate

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Forest Ecosystems 2024年第2期11卷 184-192页

作者： Zhengchao Ren Lei Liu Fang Yin Xiaoni Liu School of Earth Science and Resources Chang’an UniversityXi’an710054China research Center of Ecological Construction and Environmental Conservation in gansu Province Gansu Agricultural UniversityLanzhou730070China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China School of Land Engineering Chang’an UniversityXi’an710054China College of Pratacultural Science Gansu Agricultural UniversityLanzhou730070China

Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention ***,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate *** this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation *** achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV *** find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and ***,we observe an unexpected transition between tundra and savanna despite their geographical *** shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each ***,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing *** spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.

关键词： Potential natural vegetation Global warming Vegetation classification Predicted model CSCS

Phenology of different types of vegetation and their response to climate change in the Qilian Mountains,china

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Journal of Mountain Science 2024年第2期21卷 511-525页

作者： ZHAO Kaixin LI Xuemei ZHANG Zhengrong LIU Xinyu Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering research Center of Technologies and Applications for National Geographic State Monitoring Lanzhou 730070China gansu Provincial Engineering Laboratory for National Geographic State Monitoring Lanzhou 730070China

The Qilian Mountains(QM)possess a delicate vegetation ecosystem,amplifying the evident response of vegetation phenology to climate *** relationship between changes in vegetation growth and climate remains *** this end,we used MODIS NDVI data to extract the phenological parameters of the vegetation including meadow(MDW),grassland(GSD),and alpine vegetation(ALV))in the QM from 2002 to ***,we employed path analysis to reveal the direct and indirect impacts of seasonal climate change on vegetation ***,we decomposed the vegetation phenology in a time series using the trigonometric seasonality,Box-Cox transformation,ARMA errors,and Trend Seasonal components model(TBATS).The findings showed a distinct pattern in the vegetation phenology of the QM,characterized by a progressive shift towards an earlier start of the growing season(SOS),a delayed end of the growing season(EOS),and an extended length of the growing season(LOS).The growth cycle of MDW,GSD,and ALV in the QM species is clearly *** SOS for MDW and GSD occurred earlier,mainly between late April and August,while the SOS for ALVs occurred between mid-May and mid-August,a one-month delay compared to the other *** EOS in MDW and GSD were concentrated between late August and April and early September and early January,*** phenology exhibits distinct responses to seasonal temperature and precipitation *** advancement and delay of SOS were mainly influenced by the direct effect of spring temperatures and precipitation,which affected 19.59%and 22.17%of the study area,*** advancement and delay of EOS were mainly influenced by the direct effect of fall temperatures and precipitation,which affected 30.18%and 21.17%of the area,*** the contrary,the direct effects of temperature and precipitation in summer and winter on vegetation phenology seem less noticeable and were mainly influenced by indirect *** indirec

关键词： Vegetation phenology Time series decomposition Path Analysis Climate change

Phase evolution,hydrogen storage thermodynamics,and kinetics of ternary Mg_(98)Ho_(1.5)Fe_(0.5) alloy

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Journal of Rare Earths 2024年第9期42卷 1800-1808,I0006页

作者： Jinming Liu Hui Yong Yang Zhao Shuai Wang Yiwan Chen Baosheng Liu Jifan Hu Yanghuan Zhang College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China china Institute of Ocean Engineering(Tsing Tao) Qingdao266000China Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou014010China

Rare earth elements and transition metals have been found to improve the hydrogen storage characteristics of magnesium-based *** study investigated the Mg-Ho-Fe(MHF) ternary alloy prepared using the vacuum induction melting technique.X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),pressure-composition-temperature(PCT),and differential scanning calorimetry(DSC) were used to analyze the alloy's phase transitions,microstructure,thermodynamics,and kinetic *** results reveal that the Mg_(98)Ho_(1.5)Fe_(0.5) alloy forms a solid solution with Ho and Fe in the magnesium *** hydrogen absorption,the activated alloy transforms into a mixture of Mg/MgH_(2) phases and nanoscale HoH_(2) ***,only the MgH_(2) phase decomposes during hydrogen desorption,while the HoH_(2) phase remains unchanged,exhibiting a positive catalytic *** alloy demonstrates excellent hydrogen absorption kinetics,achieving a capacity of 5.56 wt% H_(2) within 10 min at 360℃,owing to the combined catalytic effects of Ho and *** activation energy for hydrogen desorption is found to be 135.87 kJ/mol,which is lower than that of the activation energies of pure MgH_(2) and MgFe alloys,indicating an enhancement in desorption ***,the enthalpy and entropy changes for hydrogen absorption and desorption are determined to be-70.51 kJ/mol H_(2),-125.62 J/(K·mol) H_(2),72.83 kJ/mol H_(2),and 128.95 J/(K·mol) H_(2),***,it is worth noting that the thermodynamic properties of the alloy are improved due to the catalytic effect of Ho and Fe.

关键词： Rare earths Magnesium-based hydrogen storage Hydrogen storage thermodynamics Hydrogen storage kinetics

Design and parameter optimization of air-suction wheel type of seedmetering device with elastic pad for maize

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 116-127页

作者： Yuhuan Sun Junhai Guo Linrong Shi College of Mechanical and Electrical Engineering Gansu Agricultural UniversityLanzhou 730070China College of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730070China

Due to the maize growing agronomy requires ground covered by mulch film in the arid zones of the china Northwest region,the seed-metering device must roll over,break the film,and then throw seeds into ***,the uneven ground can cause the seed-metering device to shake,reducing seed-metering *** improve the adaptability for different shapes of maize seeds,a air suction wheel type seed-metering device with elastic pad was developed for better seed extraction and bump ***,the advantages and influencing factors of the elastic pad were analyzed through four processes of metering ***,the velocity distributions of six diameters of the suction hole are compared to determine the range with ***,a one-factor experiment was conducted to analyze the pattern of the factors(the seed layer height,the critical vacuum,the rotational speed of the seed disk,and the suction hole diameter)influencing the metering seed ***,a five-level quadratic rotation orthogonal design was used to optimize the *** show that the optimal values are that the seed layer height is 40 mm,and the critical vacuum is 2.85 kPa,and the rotational speed of the seed disk is 20.1 r/*** validation experiment resulted in a 93.79%qualified index,with a 4.02%missing index and a 2.19%multiple index.

关键词： maize seeds seed-metering device with air suction elastic suction parameter optimization

Two ABCI family transporters,OsABCI15 and OsABCI16,are involved in grain-filling in rice

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Journal of Genetics and Genomics 2024年第5期51卷 492-506页

作者： Bin Ma Xiubiao Cao Xiaoyuan Li Zhong Bian Qi-Qi Zhang Zijun Fang Jiyun Liu Qun Li Qiaoquan Liu Lin Zhang Zuhua He Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Zhongshan Biological Breeding Laboratory/Key Laboratory of Plant Functional Genomics of the Ministry of education/Jiangsu Key Laboratory of Crop Genetics and Physiology Agricultural College of Yangzhou UniversityYangzhouJiangsu 225009China Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Jiangsu Key Laboratory of Crop Genetics and PhysiologyYangzhou UniversityYangzhouJiangsu 225009China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology&EcologyChinese Academy of SciencesShanghai 200032China Institute of Biotechnology Hangzhou Academy of Agricultural SciencesHangzhouZhejiang 310024China Joint International research Laboratory of Agriculture and Agri-Product Safety of the Ministry of education Yangzhou UniversityYangzhouJiangsu 225009China

Seed development is critical for plant reproduction and crop yield,with panicle seed-setting rate,grain-filling,and grain weight being key seed characteristics for yield ***,few genes are known to regulate grain ***,we identify two adenosine triphosphate(ATP)-binding cassette(ABC)I-type transporter genes,OsABCI15 and OsABCI16,involved in rice *** genes are highly expressed in developing seeds,and their proteins are localized to the plasma membrane and ***,knockout of OsABCI15 and OsABCI16 results in a significant reduction in seed-setting rate,caused predominantly by the severe empty pericarp phenotype,which differs from the previously reported low seed-setting phenotype resulting from failed *** analysis indicates that OsABCI15 and OsABCI16 participate in ion homeostasis and likely export ions between filial tissues and maternal tissues during grain ***,overexpression of OsABCI15 and OsABCI16 enhances the seed-setting rate and grain yield in transgenic plants and decreases ion accumulation in brown ***,the OsABCI15/16 orthologues in maize exhibit a similar role in kernel development,as demonstrated by their disruption in transgenic ***,ourﬁndings reveal the important roles of two ABC transporters in cereal grain filling,highlighting their value in crop yield improvement.

关键词： ABC transporters Rice Grain filling Ion homeostasis Grain yield

N,S,Br co-doped carbon dots:One-step synthesis and fluorescent detection of 6-mercaptopurine in tablet

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Journal of Pharmaceutical Analysis 2024年第2期14卷 291-293页

作者： Qi Wang Ying Cheng Lifeng Ding Shengling Li Jie Zhang Yulan Niu Ziye Jing Chemistry&Chemical Engineering Department Taiyuan Institute of TechnologyTaiyuan030008China Department of Anesthesiology First Hospital of Shanxi Medical UniversityTaiyuan030001China

6-mercaptopurine(6-MP),a purine derivative(3,7-dihydropurine-6-thione),has been utilized as an effective immunosuppressive drug for clinically treating leukemia and other autoimmune diseases[1].6-MP and its corresponding metabolites can suppress the function of RnaseH,and thus they are cytotoxic and threaten the human health[2].Therefore,the accurate quantification of 6-MP is *** date,researchers continue to expend considerable effort in developing 6-MP detection *** analysis eliminates disadvantages,such as toxic solvents,expensive equipment.

关键词： purine synthesis eliminate