期刊文献+
共找到4,290篇文章
< 1 2 215 >
每页显示 20 50 100
Celebrations and Contentions 被引量:1
1
《Beijing Review》 2009年第6期12-13,共2页
France established diplomatic relations with China on January 27,1964,becoming the first major Western power to do so.Relations between the
关键词 Celebrations and contentions
原文传递
New Record Ocean Temperatures and Related Climate Indicators in 2023 被引量:1
2
作者 Lijing CHENG John ABRAHAM +31 位作者 Kevin E.TRENBERTH Tim BOYER Michael EMANN Jiang ZHU Fan WANG Fujiang YU Ricardo LOCARNINI John FASULLO Fei ZHENG Yuanlong LI Bin ZHANG Liying WAN Xingrong CHEN Dakui WANG Licheng FENG Xiangzhou SONG Yulong LIU Franco RESEGHETTI Simona SIMONCELLI Viktor GOURETSKI Gengxin CHEN Alexey MISHONOV Jim REAGAN Karina VON SCHUCKMANN Yuying PAN Zhetao TAN Yujing ZHU Wangxu WEI Guancheng LI Qiuping REN Lijuan CAO Yayang LU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1068-1082,共15页
The global physical and biogeochemical environment has been substantially altered in response to increased atmospheric greenhouse gases from human activities.In 2023,the sea surface temperature(SST)and upper 2000 m oc... The global physical and biogeochemical environment has been substantially altered in response to increased atmospheric greenhouse gases from human activities.In 2023,the sea surface temperature(SST)and upper 2000 m ocean heat content(OHC)reached record highs.The 0–2000 m OHC in 2023 exceeded that of 2022 by 15±10 ZJ(1 Zetta Joules=1021 Joules)(updated IAP/CAS data);9±5 ZJ(NCEI/NOAA data).The Tropical Atlantic Ocean,the Mediterranean Sea,and southern oceans recorded their highest OHC observed since the 1950s.Associated with the onset of a strong El Niño,the global SST reached its record high in 2023 with an annual mean of~0.23℃ higher than 2022 and an astounding>0.3℃ above 2022 values for the second half of 2023.The density stratification and spatial temperature inhomogeneity indexes reached their highest values in 2023. 展开更多
关键词 ocean heat content SALINITY STRATIFICATION global warming CLIMATE
下载PDF
Gouge stability controlled by temperature elevation and obsidian addition in basaltic faults and implications for moonquakes 被引量:1
3
作者 Shutian Cao Fengshou Zhang +4 位作者 Mengke An Derek Elsworth Manchao He Hai Liu Luanxiao Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1273-1282,共10页
Basalt is a major component of the earth and moon crust.Mineral composition and temperature influence frictional instability and thus the potential for seismicity on basaltic faults.We performed velocitystepping shear... Basalt is a major component of the earth and moon crust.Mineral composition and temperature influence frictional instability and thus the potential for seismicity on basaltic faults.We performed velocitystepping shear experiments on basalt gouges at a confining pressure of 100 MPa,temperatures in the range of 100-400℃ and with varied obsidian mass fractions of 0-100%under wet/dry conditions to investigate the frictional strength and stability of basaltic faults.We observe a transition from velocity-neutral to velocity-weakening behaviors with increasing obsidian content.The frictional stability response of the mixed obsidian/basalt gouges is characterized by a transition from velocitystrengthening to velocity-weakening at 200℃ and another transition to velocity-strengthening at temperatures>300℃.Conversely,frictional strengths of the obsidian-bearing gouges are insensitive to temperature and wet/dry conditions.These results suggest that obsidian content dominates the potential seismic response of basaltic faults with the effect of temperature controlling the range of seismogenic depths.Thus,shallow moonquakes tend to occur in the lower lunar crust due to the corresponding anticipated higher glass content and a projected temperature range conducive to velocity-weakening behavior.These observations contribute to a better understanding of the nucleation mechanism of shallow seismicity in basaltic faults. 展开更多
关键词 Fault stability Basaltic fault Temperature elevation Obsidian content Shallow moonquakes
下载PDF
Mechanical properties and acoustic emission characteristics of soft rock with different water contents under dynamic disturbance 被引量:1
4
作者 Yujing Jiang Lugen Chen +4 位作者 Dong Wang Hengjie Luan Guangchao Zhang Ling Dong Bin Liang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期135-148,共14页
Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties... Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties and acoustic emission characteristics of soft rocks with different water contents under dynamic disturbance.The mechanical properties and acoustic emission characteristics of muddy sandstones at different water contents were analysed.Results of experimental studies show that water is a key factor in the mechanical properties of rocks,softening them,increasing their porosity,reducing their brittleness and increasing their plasticity.Under uniaxial compression,the macroscopic damage characteristics of the muddy sandstone change from mono-bevel shear damage and‘X’type conjugate bevel shear damage to a roadway bottom-drum type damage as the water content increases.Dynamic perturbation has a strengthening effect on the mechanical properties of samples with 60%and less water content,and a weakening effect on samples with 80%and more water content,but the weakening effect is not obvious.Macroscopic damage characteristics of dry samples remain unchanged,water samples from shear damage and tensile–shear composite damage gradually transformed into cleavage damage,until saturation transformation monoclinic shear damage.The evolution of acoustic emission energy and event number is mainly divided into four stages:loading stage(Ⅰ),dynamic loading stage(Ⅱ),yield failure stage(Ⅲ),and post-peak stage(Ⅳ),the acoustic emission characteristics of the stages were different for different water contents.The characteristic value of acoustic emission key point frequency gradually decreases,and the damage degree of the specimen increases,corresponding to low water content—high main frequency—low damage and high water content—low main frequency—high damage. 展开更多
关键词 Dynamic disturbance Soft rock Cyclic loading Acoustic emission Water content
下载PDF
Regulation of 2-acetyl-1-pyrroline and grain quality in early-season indica fragrant rice by nitrogen and silicon fertilization under different plantation methods 被引量:1
5
作者 Yongjian Chen Lan Dai +7 位作者 Siren Cheng Yong Ren Huizi Deng Xinyi Wang Yuzhan Li Xiangru Tang Zaiman Wang Zhaowen Mo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期511-535,共25页
Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant flavor.Plantation methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and frag... Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant flavor.Plantation methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and fragrance of fragrant rice.However,the core commercial rice production attributes,namely the head rice yield(HRY)and 2-acetyl-1-pyrroline(2-AP)content of fragrant rice,under various nitrogen and silicon(N-Si)fertilization levels and different plantation methods remain unknown.The field experiment in this study was performed in the early seasons of 2018 and 2019 with two popular indica fragrant rice cultivars(Yuxiangyouzhan and Xiangyaxiangzhan).They were grown under six N-Si fertilization treatments(combinations of two levels of Si fertilizer,0 kg Si ha^(−1)(Si0)and 150 kg Si ha^(−1)(Si1),and three levels of N fertilizer,0 kg N ha^(−1)(N0),150 kg N ha^(−1)(N1),and 220 kg N ha^(−1)(N2))and three plantation methods(artificial transplanting(AT),mechanical transplanting(MT),and mechanical direct-seeding(MD)).The results showed that the N-Si fertilization treatments and all the plantation methods significantly affected the HRY and 2-AP content and related parameters of the two different fragrant rice cultivars.Compared with the Si0N0 treatment,the N-Si fertilization treatments resulted in higher HRY and 2-AP contents.The rates of brown rice,milled rice,head rice,and chalky rice of the fragrant rice also improved with the N-Si fertilization treatments.The N-Si fertilization treatments increased the activities of N metabolism enzymes and the accumulation of N and Si in various parts of the fragrant rice,and affected their antioxidant response parameters.The key parameters for the HRY and 2-AP content were assessed by redundancy analysis.Furthermore,the structural equation model revealed that the Si and N accumulation levels indirectly affected the HRY by affecting the N metabolism enzyme activity,N use efficiency,and grain quality of fragrant rice.Moreover,high N and Si accumulation directly promoted the 2-AP content or affected the antioxidant response parameters and indirectly regulated 2-AP synthesis.The interactions of the MT method with the N-Si fertilization treatments varied in the fragrant rice cultivars in terms of the HRY and 2-AP content,whereas the MD method was beneficial to the 2-AP content in both fragrant rice cultivars under the N-Si fertilization treatments. 展开更多
关键词 fragrant rice 2-AP content head rice yield mechanical planting NITROGEN silicon
下载PDF
Effects of thawing-induced softening on fracture behaviors of frozen rock 被引量:1
6
作者 Ting Wang Hailiang Jia +2 位作者 Qiang Sun Xianjun Tan Liyun Tang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期979-989,共11页
Due to the presence of ice and unfrozen water in pores of frozen rock,the rock fracture behaviors are susceptible to temperature.In this study,the potential thawing-induced softening effects on the fracture behaviors ... Due to the presence of ice and unfrozen water in pores of frozen rock,the rock fracture behaviors are susceptible to temperature.In this study,the potential thawing-induced softening effects on the fracture behaviors of frozen rock is evaluated by testing the tension fracture toughness(KIC)of frozen rock at different temperatures(i.e.-20℃,-15℃,-12℃,-10℃,-8℃,-6℃,-4℃,-2℃,and 0℃).Acoustic emission(AE)and digital image correlation(DIC)methods are utilized to analyze the microcrack propagation during fracturing.The melting of pore ice is measured using nuclear magnetic resonance(NMR)method.The results indicate that:(1)The KIC of frozen rock decreases moderately between-20℃ and-4℃,and rapidly between-4℃ and 0℃.(2)At-20℃ to-4℃,the fracturing process,deduced from the DIC results at the notch tip,exhibits three stages:elastic deformation,microcrack propagation and microcrack coalescence.However,at-4℃e0℃,only the latter two stages are observed.(3)At-4℃e0℃,the AE activities during fracturing are less than that at-20℃ to-4℃,while more small events are reported.(4)The NMR results demonstrate a reverse variation trend in pore ice content with increasing temperature,that is,a moderate decrease is followed by a sharp decrease and-4℃ is exactly the critical temperature.Next,we interpret the thawing-induced softening effect by linking the evolution in microscopic structure of frozen rock with its macroscopic fracture behaviors as follow:from-20℃ to-4℃,the thickening of the unfrozen water film diminishes the cementation strength between ice and rock skeleton,leading to the decrease in fracture parameters.From-4℃ to 0℃,the cementation effect of ice almost vanishes,and the filling effect of pore ice is reduced significantly,which facilitates microcrack propagation and thus the easier fracture of frozen rocks. 展开更多
关键词 Frozen sandstone Different thawing temperature Fracture toughness Microcrack propagation process Unfrozen water content
下载PDF
Incorporating empirical knowledge into data-driven variable selection for quantitative analysis of coal ash content by laser-induced breakdown spectroscopy 被引量:1
7
作者 吕一涵 宋惟然 +1 位作者 侯宗余 王哲 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期148-156,共9页
Laser-induced breakdown spectroscopy(LIBS)has become a widely used atomic spectroscopic technique for rapid coal analysis.However,the vast amount of spectral information in LIBS contains signal uncertainty,which can a... Laser-induced breakdown spectroscopy(LIBS)has become a widely used atomic spectroscopic technique for rapid coal analysis.However,the vast amount of spectral information in LIBS contains signal uncertainty,which can affect its quantification performance.In this work,we propose a hybrid variable selection method to improve the performance of LIBS quantification.Important variables are first identified using Pearson's correlation coefficient,mutual information,least absolute shrinkage and selection operator(LASSO)and random forest,and then filtered and combined with empirical variables related to fingerprint elements of coal ash content.Subsequently,these variables are fed into a partial least squares regression(PLSR).Additionally,in some models,certain variables unrelated to ash content are removed manually to study the impact of variable deselection on model performance.The proposed hybrid strategy was tested on three LIBS datasets for quantitative analysis of coal ash content and compared with the corresponding data-driven baseline method.It is significantly better than the variable selection only method based on empirical knowledge and in most cases outperforms the baseline method.The results showed that on all three datasets the hybrid strategy for variable selection combining empirical knowledge and data-driven algorithms achieved the lowest root mean square error of prediction(RMSEP)values of 1.605,3.478 and 1.647,respectively,which were significantly lower than those obtained from multiple linear regression using only 12 empirical variables,which are 1.959,3.718 and 2.181,respectively.The LASSO-PLSR model with empirical support and 20 selected variables exhibited a significantly improved performance after variable deselection,with RMSEP values dropping from 1.635,3.962 and 1.647 to 1.483,3.086 and 1.567,respectively.Such results demonstrate that using empirical knowledge as a support for datadriven variable selection can be a viable approach to improve the accuracy and reliability of LIBS quantification. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) coal ash content quantitative analysis variable selection empirical knowledge partial least squares regression(PLSR)
下载PDF
Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China 被引量:1
8
作者 Jin Hu HaiBing Ruan +2 位作者 FuQing Huang ShengYang Gu XianKang Dou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期400-407,共8页
The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of G... The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions. 展开更多
关键词 International GNSS Service(IGS)Global Ionosphere Maps(GIM) Crustal Movement Observation Network of China(CMONOC) total electron content(TEC) data assessment
下载PDF
基于新型Contention网络的滚动轴承早期故障诊断方法研究
9
作者 赵俊豪 郑煜 +1 位作者 王英 王凯 《机械设计与制造工程》 2024年第3期87-91,共5页
针对滚动轴承早期故障诊断问题,为了同时建模振动信号中的高频和低频特征,实现高精度诊断,提出了一种新的模型Contention。它以一种互补的方式集成了空洞卷积和自注意力机制的优点,具有同时捕捉高频和低频信息的能力。为了验证其诊断能... 针对滚动轴承早期故障诊断问题,为了同时建模振动信号中的高频和低频特征,实现高精度诊断,提出了一种新的模型Contention。它以一种互补的方式集成了空洞卷积和自注意力机制的优点,具有同时捕捉高频和低频信息的能力。为了验证其诊断能力,首先,在完整信息原则下将振动信号连续构造成数据集;其次,搭建Contention网络并训练,其最终测试集准确度可达100%,t-SNE显示随网络层次的深入特征被明显聚类;最后,设置对照实验,将该模型与传统RNN、CNN、Transformer模型对比,证明该模型具备突出的诊断能力。 展开更多
关键词 Contention网络 空洞卷积 自注意力机制 滚动轴承 早期故障诊断
下载PDF
Longitudinal dependence of the forecast accuracy of the ionospheric total electron content in the equatorial zone
10
作者 Artem Kharakhashyan Olga Maltseva 《Geodesy and Geodynamics》 EI CSCD 2024年第5期528-541,共14页
The longitudinal dependence of the behavior of ionospheric parameters has been the subject of a number of works where significant variations are discovered.This also applies to the prediction of the ionospheric total ... The longitudinal dependence of the behavior of ionospheric parameters has been the subject of a number of works where significant variations are discovered.This also applies to the prediction of the ionospheric total electron content(TEC),which neural network methods have recently been widely used.However,the results are mainly presented for a limited set of meridians.This paper examines the longitudinal dependence of the TEC forecast accuracy in the equatorial zone.In this case,the methods are used that provided the best accuracy on three meridians:European(30°E),Southeastern(110°E)and American(75°W).Results for the stations considered are analyzed as a function of longitude using the Jet Propulsion Laboratory Global Ionosphere Map(JPL GIM)for 2015.These results are for 2 h ahead and 24 h ahead forecast.It was found that in this case,based on the metric values,three groups of architectures can be distinguished.The first group included long short-term memory(LSTM),gated recurrent unit(GRU),and temporal convolutional networks(TCN)models as a part of unidirectional deep learning models;the second group is based on the recurrent models from the first group,which were supplemented with a bidirectional algorithm,increasing the TEC forecasting accuracy by 2-3 times.The third group,which includes the bidirectional TCN architecture(BiTCN),provided the highest accuracy.For this architecture,according to data obtained for 9 equatorial stations,practical independence of the TEC prediction accuracy from longitude was observed under the following metrics(Mean Absolute Error MAE,Root Mean Square Error RMSE,Mean Absolute Percentage Error MAPE):MAE(2 h)is 0.2 TECU approximately;MAE(24 h)is 0.4 TECU approximately;RMSE(2 h)is less than 0.5 TECU except Niue station(RMSE(2 h)is 1 TECU approximately);RMSE(24 h)is in the range of 1.0-1.7 TECU;MAPE(2 h)<1%except Darwin station,MAPE(24 h)<2%.This result was confirmed by data from additional 5 stations that formed latitudinal chains in the equatorial part of the three meridians.The complete correspondence of the observational and predicted TEC values is illustrated using several stations for disturbed conditions on December 19-22,2015,which included the strongest magnetic storm in the second half of the year(min Dst=-155 nT). 展开更多
关键词 IONOSPHERE Total electron content Forecasting BiGRU BiLSTM BiTCN Temporal convolution
下载PDF
Introgression of lac6/tl1/du13 improves the palatability of japonica rice
11
作者 Yong Yang Tao Zhang +9 位作者 Yuliang Shi Yan Lu Qianfeng Li Xiaolei Fan Lichun Huang Lu Chen Xuetang Song Qing Liu Changquan Zhang Qiaoquan Liu 《The Crop Journal》 SCIE CSCD 2024年第4期1259-1265,共7页
Amylose content(AC)is a crucial determinant of the eating and cooking quality(ECQ)of rice,with low AC varieties exhibiting a softer texture and greater stickiness-attributes that enhance palatability and are desirable... Amylose content(AC)is a crucial determinant of the eating and cooking quality(ECQ)of rice,with low AC varieties exhibiting a softer texture and greater stickiness-attributes that enhance palatability and are desirable in specific culinary contexts.To harness these traits,significant efforts have been made to manipulate AC to improve rice ECQ.Our research utilized the MutMap+approach to identify LAC6/TL1,a gene that is an allele of Du13,responsible for low AC.LAC6 encodes a C2H2 zinc finger protein,which specifically increases the splicing efficiency of the Wxb allele without affecting the Wxa allele.Functional studies of LAC6 revealed that its proper integration could rectify the undesirable AC phenotype,whereas mutations within this gene led to reduced AC and were associated with shorter grain length and decreased thousand-grain weight.Despite these drawbacks,such mutations positively impact rice palatability,presenting a trade-off between grain size and eating quality.To address the challenges posed by the reduced grain weight associated with LAC6 mutations,we developed a specific molecular marker for LAC6,which has been effectively used in breeding programs to select lac6/tl1/du13 homozygous individuals with larger grain size.Our findings demonstrate that the“small grain”trait associated with lac6/tl1/du13 can be effectively mitigated through combined phenotype-based and marker-assisted selection.This study highlights the potential of lac6/tl1/du13 as a valuable gene for breeding novel,high-quality soft rice varieties through targeted breeding strategies. 展开更多
关键词 Rice Dull endosperm Amylose content WX BREEDING
下载PDF
Effect of overheating-induced minor addition on Zr-based metallic glasses
12
作者 杨福 薄振兴 +7 位作者 黄瑶 王雨田 孙博阳 鲁振 孙保安 柳延辉 汪卫华 潘明祥 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期118-125,共8页
Melt treatment is well known to have an important influence on the properties of metallic glasses(MGs).However,for the MGs quenched from different melt temperatures with a quartz tube,the underlying physical origin re... Melt treatment is well known to have an important influence on the properties of metallic glasses(MGs).However,for the MGs quenched from different melt temperatures with a quartz tube,the underlying physical origin responsible for the variation of properties remains poorly understood.In the present work,we systematically studied the influence of melt treatment on the thermal properties of a Zr50Cu36Al14 glass-forming alloy and unveiled the microscopic origins.Specifically,we quenched the melt at different temperatures ranging from 1.1Tl to 1.5Tl(Tl is the liquidus temperature)to obtain melt-spun MG ribbons and investigated the variation of thermal properties of the MGs upon heating.We found that glass transition temperature,Tg,increases by as much as 36 K,and the supercooled liquid region disappears in the curve of differential scanning calorimetry when the melt is quenched at a high temperature up to 1.5Tl.The careful chemical analyses indicate that the change in glass transition behavior originates from the incorporation of oxygen and silicon in the molten alloys.The incorporated oxygen and silicon can both enhance the interactions between atoms,which renders the cooperative rearrangements of atoms difficult,and thus enhances the kinetic stability of the MGs. 展开更多
关键词 metallic glass thermal properties melt treatment OVERHEATING oxygen content
下载PDF
SFNet:Stellar Feature Network with CWT for Stellar Spectra Recognition
13
作者 Hao Fu Peng Liu +1 位作者 Xuan Qi Xue Mei 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第9期260-270,共11页
Stellar spectral classification is crucial in astronomical data analysis.However,existing studies are often limited by the uneven distribution of stellar samples,posing challenges in practical applications.Even when b... Stellar spectral classification is crucial in astronomical data analysis.However,existing studies are often limited by the uneven distribution of stellar samples,posing challenges in practical applications.Even when balancing stellar categories and their numbers,there is room for improvement in classification accuracy.This study introduces a Continuous Wavelet Transform using the Super Morlet wavelet to convert stellar spectra into wavelet images.A novel neural network,the Stellar Feature Network,is proposed for classifying these images.Stellar spectra from Large Sky Area Multi-Object Fiber Spectroscopic Telescope DR9,encompassing five equal categories(B,A,F,G,K),were used.Comparative experiments validate the effectiveness of the proposed methods and network,achieving significant improvements in classification accuracy. 展开更多
关键词 methods data analysis-techniques image processing-stars imaging-galaxies stellar content
下载PDF
Lysine 2-hydroxyisobutyrylation levels determined adipogenesis and fat accumulation in adipose tissue in pigs
14
作者 Enfa Yan Mingyang Tan +4 位作者 Ning Jiao Linjuan He Boyang Wan Xin Zhang Jingdong Yin 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2093-2105,共13页
Background Excessive backfat deposition lowering carcass grade is a major concern in the pig industry,especially in most breeds of obese type pigs.The mechanisms involved in adipogenesis and fat accumulation in pigs r... Background Excessive backfat deposition lowering carcass grade is a major concern in the pig industry,especially in most breeds of obese type pigs.The mechanisms involved in adipogenesis and fat accumulation in pigs remain unclear.Lysine 2-hydroxyisobutyrylation(Khib),is a novel protein post-translational modification(PTM),which play an important role in transcription,energy metabolism and metastasis of cancer cells,but its role in adipogenesis and fat accumulation has not been shown.Results In this study,we first analyzed the modification levels of acetylation(Kac),Khib,crotonylation(Kcr)and succinylation(Ksu)of fibro-adipogenic progenitors(FAPs),myogenic precursors(Myo)and mesenchymal stem cells(MSCs)with varied differentiation potential,and found that only Khib modification in FAPs was significantly higher than that in MSCs.Consistently,in parallel with its regulatory enzymes lysine acetyltransferase 5(KAT5)and histone deacetylase 2(HDAC2)protein levels,the Khib levels increased quadratically(P<0.01)during adipogenic differentiation of FAPs.KAT5 knockdown in FAPs inhibited adipogenic differentiation,while HDAC2 knockdown enhanced adipogenic differentiation.We also demonstrated that Khib modification favored to adipogenic differentiation and fat accumulation by comparing Khib levels in FAPs and backfat tissues both derived from obese-type pigs(Laiwu pigs)and lean-type pigs(Duroc pigs),respectively.Accordingly,the expression patterns of KAT5 and HDAC2 matched well to the degree of backfat accumulation in obese-and lean-type pigs.Conclusions From the perspective of protein translational modification,we are the first to reveal the role of Khib in adipogenesis and fat deposition in pigs,and provided new clues for the improvement of fat accumulation and distribution as expected via genetic selection and nutritional strategy in obese-type pigs. 展开更多
关键词 ADIPOGENESIS BACKFAT Fat accumulation 2-Hydroxyisobutyrylation Intramuscular fat content PIGS
下载PDF
Quantitative characterizations of anisotropic dynamic properties in organic-rich shale with different kerogen content
15
作者 Jian-Yong Xie Yan-Ping Fang +4 位作者 Xing-Hua Wu Jian'er Zhao Jun-Cheng Dai Jun-Xing Cao Ji-Xin Deng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期855-865,共11页
Understanding the quantitative responses of anisotropic dynamic properties in organic-rich shale with different kerogen content(KC)is of great significance in hydrocarbon exploration and development.Conducting control... Understanding the quantitative responses of anisotropic dynamic properties in organic-rich shale with different kerogen content(KC)is of great significance in hydrocarbon exploration and development.Conducting controlled experiments with a single variable is challenging for natural shales due to their high variations in components,diagenesis conditions,or pore fluid.We employed the hot-pressing technique to construct 11 well-controlled artificial shale with varying KC.These artificial shale samples were successive machined into prismatic shape for ultrasonic measurements along different directions.Observations revealed bedding perpendicular P-wave velocities are more sensitive to the increasing KC than bedding paralleling velocities due to the preferential alignments of kerogen.All elastic stiffnesses except C_(13)are generally decreasing with the increasing KC,the variation of C_(1) and C_(33)on kerogen content are more sensitive than those of C_(44)and C_(66).Apparent dynamic mechanical parameters(v and E)were found to have linear correlation with the true ones from complete anisotropic equations independent of KC,which hold value towards the interpretation of well logs consistently across formations,Anisotropic mechanical parameters(ΔE and brittlenessΔB)tend to decrease with the reducing KC,withΔB showing great sensitivity to KC variations.In the range of low KC(<10%),the V_(P)/V_(S) ratio demonstrated a linearly negative correlation with KC,and the V_(P)/V_(S) ratio magnitude of less than 1.75may serve as a significant characterization for highly organic-rich(>10%)shale,compilation of data from natural organic rich-shales globally verified the similar systematic relationships that can be empirically used to predict the fraction of KC in shales. 展开更多
关键词 Elastic properties Organic shale ANISOTROPY Kerogen content Physical modeling
下载PDF
Digital twin driven and intelligence enabled content delivery in end-edge-cloud collaborative 5G networks
16
作者 Bo Yi Jianhui Lv +2 位作者 Xingwei Wang Lianbo Ma Min Huang 《Digital Communications and Networks》 SCIE CSCD 2024年第2期328-336,共9页
The rapid development of 5G/6G and AI enables an environment of Internet of Everything(IoE)which can support millions of connected mobile devices and applications to operate smoothly at high speed and low delay.Howeve... The rapid development of 5G/6G and AI enables an environment of Internet of Everything(IoE)which can support millions of connected mobile devices and applications to operate smoothly at high speed and low delay.However,these massive devices will lead to explosive traffic growth,which in turn cause great burden for the data transmission and content delivery.This challenge can be eased by sinking some critical content from cloud to edge.In this case,how to determine the critical content,where to sink and how to access the content correctly and efficiently become new challenges.This work focuses on establishing a highly efficient content delivery framework in the IoE environment.In particular,the IoE environment is re-constructed as an end-edge-cloud collaborative system,in which the concept of digital twin is applied to promote the collaboration.Based on the digital asset obtained by digital twin from end users,a content popularity prediction scheme is firstly proposed to decide the critical content by using the Temporal Pattern Attention(TPA)enabled Long Short-Term Memory(LSTM)model.Then,the prediction results are input for the proposed caching scheme to decide where to sink the critical content by using the Reinforce Learning(RL)technology.Finally,a collaborative routing scheme is proposed to determine the way to access the content with the objective of minimizing overhead.The experimental results indicate that the proposed schemes outperform the state-of-the-art benchmarks in terms of the caching hit rate,the average throughput,the successful content delivery rate and the average routing overhead. 展开更多
关键词 Digital twin IoE Content delivery CACHING Routing
下载PDF
The Caching and Pricing Strategy for Information-Centric Networking with Advertisers’Participation
17
作者 Zheng Quan Yan Wenliang +4 位作者 Wu Rong Tan Xiaobin Yang Jian Yuan Liu Xu Zhenghuan 《China Communications》 SCIE CSCD 2024年第3期283-295,共13页
As users’access to the network has evolved into the acquisition of mass contents instead of IP addresses,the IP network architecture based on end-to-end communication cannot meet users’needs.Therefore,the Informatio... As users’access to the network has evolved into the acquisition of mass contents instead of IP addresses,the IP network architecture based on end-to-end communication cannot meet users’needs.Therefore,the Information-Centric Networking(ICN)came into being.From a technical point of view,ICN is a promising future network architecture.Researching and customizing a reasonable pricing mechanism plays a positive role in promoting the deployment of ICN.The current research on ICN pricing mechanism is focused on paid content.Therefore,we study an ICN pricing model for free content,which uses game theory based on Nash equilibrium to analysis.In this work,advertisers are considered,and an advertiser model is established to describe the economic interaction between advertisers and ICN entities.This solution can formulate the best pricing strategy for all ICN entities and maximize the benefits of each entity.Our extensive analysis and numerical results show that the proposed pricing framework is significantly better than existing solutions when it comes to free content. 展开更多
关键词 ADVERTISERS CACHE free content Information-Centric Networking pricing strategy
下载PDF
Evaluation and Influencing Factors on Particle Agglomeration in RAP
18
作者 唐伟 李宁 +4 位作者 ZHUANG Yuan ZHAN He YU Xin WU Wenxiu DING Gongying 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期60-68,共9页
Asphalt extraction test and scanning electron microscopy(SEM) were used for analysis of agglomerations of reclaimed asphalt pavement(RAP) particles. In order to quantify the agglomeration degree of RAP, the fineness m... Asphalt extraction test and scanning electron microscopy(SEM) were used for analysis of agglomerations of reclaimed asphalt pavement(RAP) particles. In order to quantify the agglomeration degree of RAP, the fineness modulus ratio(FMR) and the percentage loss index(PLI) were proposed. In addition, grey correlation analysis was conducted to discuss the relationship between particle agglomerations and RAP size,asphalt content(AC), and surface area. Two indexes indicate that the agglomeration degree increases in general as the RAP size reduces. This can be attributed to that particles are prone to agglomeration in the case of higher AC. Based on the SEM images and the material composition of RAP, the particle agglomeration in RAP can be classified into weak agglomeration and strong agglomeration. Grey correlation analysis shows that AC is the crucial factor affecting the agglomeration degree and RAP variability. In order to produce consistent and stable reclaimed mixtures, disposal measures of RAP are suggested to lower the AC of RAP. 展开更多
关键词 RAP particle agglomeration grey correlation analysis asphalt content
下载PDF
Straw interlayer improves sunflower root growth:Evidence from moisture and salt migration and the microbial community in saline-alkali soil
19
作者 Mengmeng Chen Guoli Wang +9 位作者 Yupeng Jing Jie Zhou Jiashen Song Fangdi Chang Ru Yu Jing Wang Weini Wang Xia Sun Hongyuan Zhang Yuyi Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第11期3870-3881,共12页
A straw interlayer added to soil can effectively reduce soil salinity effects on plant growth,however,the effects of soil moisture,salt and microbial community composition on plant growth under a straw interlayer are ... A straw interlayer added to soil can effectively reduce soil salinity effects on plant growth,however,the effects of soil moisture,salt and microbial community composition on plant growth under a straw interlayer are unclear.A rhizobox study was conducted to investigate the role of straw interlayer thickness on soil moisture,salt migration,microbial community composition,as well as root growth in sunflower.The study included four treatments:Control(no straw interlayer);S3(straw interlayer of 3.0 cm);S5(straw interlayer of 5.0 cm);S7(straw interlayer of 7.0 cm).Straw interlayer treatments increased soil moisture by 8.2–11.0%after irrigation and decreased soil salt content after the bud stage in 0–40 cm soil.Total root length,total root surface area,average root diameter,total root volume and the number of root tips of sunflower plants were higher under straw interlayer treatments than in the control,and were the highest under the S5 treatment.This stimulated root growth was ascribed to the higher abundance of Chloroflexi and Verrucomicrobia bacteria in soil with a straw interlayer,which was increased by 55.7 and 54.7%,respectively,in the S5 treatment.Addition of a straw interlayer of 5 cm thickness is a practical and environmentally feasible approach for improving sunflower root growth in saline-alkali soil. 展开更多
关键词 saline-alkali soil RHIZOBOX soil water soil salt content bacterial community
下载PDF
Natural variation of an autophagy-family gene among rice subspecies affects grain size and weight
20
作者 Shiying Huang Peng Wang +10 位作者 Caijing Li Qingwen Zhou Tao Huang Yicong Cai Qin Cheng Hui Wang Qi Zhong Zhihao Chen Liping Chen Haohua He Jianmin Bian 《The Crop Journal》 SCIE CSCD 2024年第1期121-132,共12页
Elucidating the genetic basis of natural variation in grain size and weight among rice varieties can help breeders develop high-yielding varieties.We identified a novel gene,GW3a(Grain Weight 3a)(LOC_Os03g27350),that ... Elucidating the genetic basis of natural variation in grain size and weight among rice varieties can help breeders develop high-yielding varieties.We identified a novel gene,GW3a(Grain Weight 3a)(LOC_Os03g27350),that affects rice grain size and weight.gw3a mutants showed higher total starch content and dry matter accumulation than the wild type(WT),Nipponbare,suggesting that GW3a negatively regulates grain size and weight.Moreover,our study found that GW3a interacted with OsATG8 by cleaving it,suggesting that GW3a may be involved in the assembly of autophagosomes and starch degradation in plants.The haplotype analysis of GW3a showed functional differences between indica and japonica rice.Taken together,we conclude that GW3a is expressed in the autophagosome pathway regulating starch metabolism in rice,affecting yield-related traits,such as grain size,grain weight and thousand grain weight(TGW).Our findings also shed new light on autophagy-mediated yield trait regulation,proposing a possible strategy for the genetic improvement of high-yield germplasm in rice. 展开更多
关键词 Grain size GW3a AUTOPHAGY Starch content
下载PDF
上一页 1 2 215 下一页 到第
使用帮助 返回顶部