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Transcriptomic Regulation Analysis Reveals Salt-Induced Response at Early Seedling Stages among Three Rice Genotypes
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作者 Sirinthorn KONGPRAPHRUT LÜ Yang +4 位作者 WANG Yueying Mohamed HAZMAN TONG Hanhua QIAN Qian GUO Longbiao 《Rice science》 2025年第5期607-611,I0032-I0065,共39页
Salt stress is a critical factor affecting the growth and yield of rice.Egypt,the largest rice producer in North Africa and the Middle East,is facing contrasting challenges related to salinity in its agroecosystems.In... Salt stress is a critical factor affecting the growth and yield of rice.Egypt,the largest rice producer in North Africa and the Middle East,is facing contrasting challenges related to salinity in its agroecosystems.In this study,we compared the salt-induced responses among three rice varieties:Giza 176(Egyptian variety),Kaituodao(Chinese variety),and Pokkali(Sri Lanka variety,used as control)under normal and saline stress(100 mmol/L NaCl)conditions at two seedling stages through RNA-seq expression analysis.Giza 176 displayed a salt tolerance score of 7 on the SES(Standard Evaluation Score).Its transcriptome showed dynamic changes,with the number of upregulated genes increasing from 180 to 735,and downregulated genes increasing from 918 to 2930 from the one-week to two-week stress stages,with activated pathways in ion transport,reactive oxygen species(ROS)scavenging,and protein biosynthesis. 展开更多
关键词 protein biosynthesis ion transport reactive oxygen species salt stress seedling stages transcriptomic regulation rice genotypes RNA seq
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Transcriptomic profiling of cardiac development in Bama Xiang pigs across key developmental stages
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作者 Sheng-Nan Wang Wen-Jie Tian +4 位作者 Deng-Ke Pan Tang Hai Yue-Hui Ma Dan-Dan Wang Lin Jiang 《Zoological Research》 2025年第3期634-646,共13页
Pigs have emerged as valuable large-animal models for cardiac xenotransplantation;however,the temporal dynamics of myocardial development in this species remains insufficiently defined.This study analyzed gene express... Pigs have emerged as valuable large-animal models for cardiac xenotransplantation;however,the temporal dynamics of myocardial development in this species remains insufficiently defined.This study analyzed gene expression patterns across four key developmental stages(neonatal,juvenile,sexual maturity,and adulthood)to delineate the molecular mechanisms driving porcine myocardial development.Increases in heart weight were accompanied by proportional expansion of myocardial fiber area and chamber size,reflecting coordinated structural development.Transcriptomic profiling of myocardial tissue by RNA sequencing(RNA-seq)identified 2189 differentially expressed genes(DEGs)across stage comparisons.Short time-series expression miner(STEM)analysis classified these DEGs into four major expression clusters enriched in pathways associated with myocardial development,immune responses,cell proliferation,and metabolic processes.Among 359 DEGs conserved across all developmental stages,six candidate genes were strongly associated with myocardial development.Reverse transcription-quantitative real-time polymerase chain reaction(RT-qPCR)confirmed a significant correlation between the expression of these candidate genes and myocardial development in porcine tissue.These findings establish a transcriptomic framework for porcine myocardial maturation and provide a molecular basis for advancing cardiac xenotransplantation. 展开更多
关键词 Cardiac tissue Bama Xiang pig Multiple stages Heart development TRANSCRIPTOMICS
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Cassiterite U-Pb geochronology of the Sareshenke Tin deposit in the East Junggar:Implications for the two stages of tin mineralization
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作者 Su-xia Peng Kai Weng +3 位作者 Xiao-qin Quan Bo Chen Zhao-wei Zhang Chao Sun 《China Geology》 2025年第4期862-864,I0003,共4页
1.Objective The Eastern Junggar Kalamaili region in Xinjiang constitutes a significant tin metallogenic belt in northwest China(Fig.1a).It hosts four independent tin deposits-Kamusite,Ganliangzi,Beilekuduke,and Saresh... 1.Objective The Eastern Junggar Kalamaili region in Xinjiang constitutes a significant tin metallogenic belt in northwest China(Fig.1a).It hosts four independent tin deposits-Kamusite,Ganliangzi,Beilekuduke,and Sareshenke-from west to east,supplemented by two tin mineralized points,namely Hongtujingzi and Sujiquan(Figs.1b).according to the ore type and the composition of gangue minerals,the tin deposits in the region are classified into two groups:Quartz vein type and greisen type,with the Sareshenke deposit ascribed to the former and the remainder to the latter. 展开更多
关键词 gangue mineralsthe sareshenke tin deposit East Junggar CASSITERITE U Pb geochronology two stages tin mineralization
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Transformer-Based Contrastive Learning Method for Automated Sleep Stages Classification
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作者 MA Jin REN Ze +3 位作者 ZHANG Tongtong DING Ying LU Yilei PENG Yinghong 《Journal of Shanghai Jiaotong university(Science)》 2025年第4期720-732,共13页
Automated sleep stages classification facilitates clinical experts in conducting treatment for sleep disorders,as it is more time-efficient concerning the analysis of whole-night polysomnography(PSG).However,most of t... Automated sleep stages classification facilitates clinical experts in conducting treatment for sleep disorders,as it is more time-efficient concerning the analysis of whole-night polysomnography(PSG).However,most of the existing research only focused on public databases with channel systems incompatible with the current clinical measurements.To narrow the gap between theoretical models and real clinical practice,we propose a novel deep learning model,by combining the vision transformer with supervised contrastive learning,realizing the efficient sleep stages classification.Experimental results show that the model facilitates an easier classification of multi-channel PSG signals.The mean F1-scores of 79.2%and 76.5%on two public databases outperform the previous studies,showing the model’s great capability,and the performance of the proposed method on the children’s small database also presents a high mean accuracy of 88.6%.Our proposed model is validated not only on the public databases but the provided clinical database to strictly evaluate its clinical usage in practice. 展开更多
关键词 sleep stages classification vision transformer contrastive learning polysomnography(PSG)signal
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Sexually differentiated decision-making involves faster recruitment in the early stages for the Tibetan antelopes Pantholops hodgsonii
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作者 Qin Zhu Jian Guan +6 位作者 Tianya Lei Kun Xuan Sile Guo Yumeng Zhao Changjian Fu Le Yang Zhongqiu Li 《Current Zoology》 2025年第1期124-135,共12页
Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studie... Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studies on collective behavior in small animals such as fish and insects are well-established,similar research on large wild animals remains challenging due to the limited availability of sufficient and systematic field data.Here,we aimed to explore the collective decision-making pattern and its sexual difference for the dimorphic Tibetan antelopes Pantholops hodgsonii(chiru)in Xizang Autonomous Region,China,by analyzing individual leadership distribution,as well as the joining process,considering factors such as calving stages and joining ranks.The distinct correlations of decision participants’ratio with group size and decision duration underscore the trade-off between accuracy and speed in decision-making.Male antelopes display a more democratic decision-making pattern,while females exhibit more prompt responses after calving at an early stage.This study uncovers a partially shared decision-making strategy among Tibetan antelopes,suggesting flexible self-organization in group decision processes aligned with animal life cycle progression. 展开更多
关键词 calving stage DECISION-MAKING LEADERSHIP sexual differences Tibetan antelopes
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Rhizosphere bacterial communities of Agriophyllum squarrosum(L.)Moq.during different developmental stages
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作者 ZHANG Shengnan GAO Haiyan +7 位作者 YANG Shanshan ZHANG Lei YAN Deren HUANG Haiguang YANG Zhiguo LI Junwen TANG Yuekun XU Hongbin 《Journal of Arid Land》 2025年第9期1282-1296,共15页
The rhizosphere bacteria play crucial roles in plant health and growth as they are involved in assimilating nutrients and resisting adverse conditions such as nutrient stress,drought,and wind erosion.Agriophyllum squa... The rhizosphere bacteria play crucial roles in plant health and growth as they are involved in assimilating nutrients and resisting adverse conditions such as nutrient stress,drought,and wind erosion.Agriophyllum squarrosum(L.)Moq.is a pioneer plant used in sand fixation due to its strong resistance to drought and wind erosion.However,the bacterial community characteristics and ecological function in the rhizosphere of A.squarrosum are poorly understood.In this study,soil samples were collected from different developmental stages(seedling stage,vegetative stage,reproductive stage,and withering stage)of A.squarrosum.Illumina Miseq sequencing was used to detect differences in soil bacterial abundance.The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt)program was used to predict bacterial functions,and the relationships among bacteria,functional populations,and soil nutrients were examined using a heatmap analysis.The results showed that the Shannon and Sobs indices of rhizosphere bacteria were significantly higher during the reproductive stage than during the other stages.Pantoea sp.(7.03%)was the dominant genus during the seedling stage;Arthrobacter sp.was the dominant genus during the vegetative(13.94%),reproductive(7.57%),and withering(12.30%)stages.The relative abundances of Chloroflexi,Acidobacteria,and Gemmatimonadetes were significantly high during the reproductive stage.According to the PICRUSt analysis,membrane transport,signal transduction,and environmental adaptation of the bacterial functional population occurred during the seedling stage.Carbohydrate metabolism increased during the vegetative stage,while energy metabolism,lipid metabolism,and biosynthesis of other secondary metabolites of the bacterial functional population significantly increased during the reproductive stage.The abundances of bacterial communities,functional genes,and soil nutrients were synergistically altered during various developmental stages.Our findings suggest that the developmental stages of A.squarrosum play a significant role in defining the composition and structure of bacterial communities in the rhizosphere.The results will provide a basis for better prediction and understanding of soil bacterial metabolic potential and functions of A.squarrosum rhizosphere in sandy areas. 展开更多
关键词 bacterial diversity developmental stage DROUGHT functional prediction soil nutrient wind erosion
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Polystyrene microplastics affect the early life stages of large yellow croaker Pseudosciaena crocea
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作者 Hailing YANG Fangzhu WU +6 位作者 Fangping CHEN Jiangning ZENG Qikun YANG Lukuo MA Tianqi ZHAI Yu ZHOU Wei HUANG 《Journal of Oceanology and Limnology》 2025年第2期644-655,共12页
Microplastics(MPs)have garnered significant international scrutiny as an emerging environmental pollutant,constituting one of the four principal global environmental threats and posing potential health hazards to huma... Microplastics(MPs)have garnered significant international scrutiny as an emerging environmental pollutant,constituting one of the four principal global environmental threats and posing potential health hazards to humans.However,data on the impact of MPs on the early life of the commercially important fish remain limited.In this study,polystyrene microspheres(PS-MPs)(1 and 5μm)were used to investigate the effects of MPs on the growth,development,and metabolism in early life stages of large yellow croaker Pseudosciaena crocea.Results indicate that MPs were enriched in the gastrointestinal tract and gills of the fish.In addition,PS-MPs(1μm)exhibited no obvious effects on embryo hatching and heart rates,while increased the mortality rate(23.00%vs.control 14.99%)and decreased the body length(4098.61±447.03μm vs.control with 2827.04±254.75μm)of the larvae at the highest exposure concentration(5×10^(4)items/L).Metabolomics analysis revealed that PS-MPs(5μm)induced mild perturbations in phospholipid metabolism,specifically alterations in phosphatidylethanolamine(PE)levels.These changes influenced the cell membranes of juvenile fish,and consequently elicited inflammatory responses,disrupted lipid homeostasis,and affected other critical physiological processes.Ultimately,these effects may avoid the growth retardation and potential mortality.Therefore,PS-MPs could affect negatively the fish health in the early life stage,which has implications for aquatic ecosystems. 展开更多
关键词 polystyrene microplastic(PS-MP) early life stage Pseudosciaena crocea large yellow croaker DEVELOPMENT METABOLOMIC
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Effect of sea surface temperature during critical early life history stages of Portunus trituberculatus on later yield
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作者 Kaiming XIA Baogui LIU +1 位作者 Jiale QIAO Yingbin WANG 《Journal of Oceanology and Limnology》 2025年第1期313-325,共13页
The early life stages of marine organisms are pivotal in shaping community dynamics and resource availability.In this study,we focused on Portunus trituberculatus,a crustacean integral to China's fisheries economy... The early life stages of marine organisms are pivotal in shaping community dynamics and resource availability.In this study,we focused on Portunus trituberculatus,a crustacean integral to China's fisheries economy,and examined the effect of sea surface temperature(SST)in its critical early life stages on subsequent yields.To analyze the correlation between SST in different larval stages and the corresponding yield of P.trituberculatus,we simulated the transport and distribution of larvae from 2014 to 2022 by employing circulation models and Lagrangian particle tracking experiments(LPTE).In the five years(2014,2015,2016,2019,and 2020),particles were transported in a northwestern direction and moved in the direction of low SST.The distribution of particles in the megalopa stage(M stage)were located in the region of the lower temperature.In 2017,2018,and 2021,the particles were transported in a northeastern direction but they did not move with the gradient of low SST in these years,and the particles in the last M stage were located in the region where the SST was at the peak of the time period.In 2022,the distribution was observed for most of the particles in the southwestern part of Zhejiang coast,a small part of them were transported in the northwestern direction and a small amount of particles was distributed offshore along the northern area of the Zhejiang coast.The correlations between the SST at each stage of larvae with the corresponding year's yield showed that the yield of P.trituberculatus decreased significantly(R=-0.772,P=0.015)with increasing SST at the M stage.This study preliminarily explains the correlation between SST at the larval stage and the yield of P.trituberculatus and provides essential information for scientific stock enhancement in the future. 展开更多
关键词 East China Sea swimming crab(Portunus trituberculatus) larval stage development Lagrangian particle tracking spatial-temporal dynamics sea surface temperature
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Single-cell profiling of the pig cecum at various developmental stages 被引量:2
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作者 Yan-Yuan Xiao Qing Zhang +9 位作者 Fei Huang Lin Rao Tian-Xiong Yao Si-Yu Yang Lei Xie Xiao-Xiao Zou Li-Ping Cai Jia-Wen Yang Bin Yang Lu-Sheng Huang 《Zoological Research》 SCIE CSCD 2024年第1期55-68,共14页
The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding... The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity,functional heterogeneity,and their importance in intestinal tract development and disease.Although such profiling has been extensively conducted in humans and mice,the single-cell gene expression landscape of the pig cecum remains unexplored.Here,single-cell RNA sequencing was performed on 45572 cells obtained from seven cecal samples in pigs at four different developmental stages(days(D)30,42,150,and 730).Analysis revealed 12 major cell types and 38 subtypes,as well as their distinctive genes,transcription factors,and regulons,many of which were conserved in humans.An increase in the relative proportions of CD8^(+)T and Granzyme A(low expression)natural killer T cells(GZMA^(low)NKT)cells and a decrease in the relative proportions of epithelial stem cells,Tregs,RHEX^(+)T cells,and plasmacytoid dendritic cells(pDCs)were noted across the developmental stages.Moreover,the post-weaning period exhibited an up-regulation in mitochondrial genes,COX2 and ND2,as well as genes involved in immune activation in multiple cell types.Cell-cell crosstalk analysis indicated that IBP6^(+)fibroblasts were the main signal senders at D30,whereas IBP6^(−)fibroblasts assumed this role at the other stages.NKT cells established interactions with epithelial cells and IBP6^(+)fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs.This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages. 展开更多
关键词 Single-cell RNA-seq CECUM Bama Xiang pigs Various developmental stages Cellular heterogeneity
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Classification of single tree decay stages from combined airborne LiDAR data and CIR imagery 被引量:1
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作者 Tsz-Chung Wong Abubakar Sani-Mohammed +3 位作者 Jinhong Wang Puzuo Wang Wei Yao Marco Heurich 《Geo-Spatial Information Science》 CSCD 2024年第6期2076-2091,共16页
Understanding forest health is of great importance for the conservation of the integrity of forest ecosystems.The monitoring of forest health is,therefore,indispensable for the long-term conservation of forests and th... Understanding forest health is of great importance for the conservation of the integrity of forest ecosystems.The monitoring of forest health is,therefore,indispensable for the long-term conservation of forests and their sustainable management.In this regard,evaluating the amount and quality of dead wood is of utmost interest as they are favorable indicators of biodiversity.Apparently,remote sensing-based Machine Learning(ML)techniques have proven to be more efficient and sustainable with unprecedented accuracy in forest inventory.However,the application of these techniques is still in its infancy with respect to dead wood mapping.This study,for the first time,automatically categorizing individual coniferous trees(Norway spruce)into five decay stages(live,declining,dead,loose bark,and clean)from combined Airborne Laser Scanning(ALS)point clouds and color infrared(CIR)images using three different ML methods−3D point cloud-based deep learning(KPConv),Convolutional Neural Network(CNN),and Random Forest(RF).First,CIR colorized point clouds are created by fusing the ALS point clouds and color infrared images.Then,individual tree segmentation is conducted,after which the results are further projected onto four orthogonal planes.Finally,the classification is conducted on the two datasets(3D multispectral point clouds and 2D projected images)based on the three ML algorithms.All models achieved promising results,reaching overall accuracy(OA)of up to 88.8%,88.4%and 85.9%for KPConv,CNN and RF,respectively.The experimental results reveal that color information,3D coordinates,and intensity of point clouds have significant impact on the promising classification performance.The performance of our models,therefore,shows the significance of machine/deep learning for individual tree decay stages classification and landscape-wide assessment of the dead wood amount and quality by using modern airborne remote sensing techniques.The proposed method can contribute as an important and reliable tool for monitoring biodiversity in forest ecosystems. 展开更多
关键词 Tree decay stages Airborne Laser Scanning(ALS) color infrared imagery(CIR) Machine Learning(ML) dead wood
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Fluid inclusions and hydrocarbon accumulation stages of the Chang 7_(3) sub-member in the Zhijing-Ansai area in the Ordos Basin
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作者 Yulin Chen Nan Wu +1 位作者 Yong Feng Jian Wang 《Episodes》 2024年第2期265-278,共14页
Influenced by Late Cretaceous tectonic uplift,fluid inclusion techniques were employed to determine the hydrocarbon accumulation stages of the Chang 7_(3) sub-member in the Zhijing-Ansai area.There were two fluorescen... Influenced by Late Cretaceous tectonic uplift,fluid inclusion techniques were employed to determine the hydrocarbon accumulation stages of the Chang 7_(3) sub-member in the Zhijing-Ansai area.There were two fluorescent oil inclusions in the Chang 7_(3) sub-member.The green fluorescent oil inclusions indicated the relatively low-maturity oil,the homogenization temperatures of coeval aqueous inclusions were 83.8-89.5℃.The blue fluorescent oil inclusions indicated the relatively high-maturity oil,the homogenization temperatures of coeval aqueous inclusions exhibited two peaks which were 90.6-109.4℃and 110.1-137.4℃.Combining the burial-thermal history of four wells,there were three stages of hydrocarbon accumulation.A smallscale charging of the relatively low-maturity oil occurred around 131-122 Ma.During the large-scale charging of the high-maturity oil,the hydrocarbon generation of source rock peaked(c.114 to 100 Ma).Late tectonic uplift resulted in an oil adjustment stage(88-72 Ma),corresponding to the high-maturity oil charging time. 展开更多
关键词 hydrocarbon accumulation Chang sub member fluid inclusions homogenization temperatures fluorescent oil inclusions determine hydrocarbon accumulation stages coeval aqueous inclusions fluorescent oil
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Present and future of new systemic therapies for early and intermediate stages of hepatocellular carcinoma 被引量:6
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作者 Juan Jose Urquijo-Ponce Carlos Alventosa-Mateu +3 位作者 Mercedes Latorre-Sánchez Inmaculada Castelló-Miralles Moisés Diago Hepatology Unit 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2512-2522,共11页
Hepatocellular carcinoma(HCC)is a high mortality neoplasm which usually appears on a cirrhotic liver.The therapeutic arsenal and subsequent prognostic outlook are intrinsically linked to the HCC stage at diagnosis.Not... Hepatocellular carcinoma(HCC)is a high mortality neoplasm which usually appears on a cirrhotic liver.The therapeutic arsenal and subsequent prognostic outlook are intrinsically linked to the HCC stage at diagnosis.Notwithstanding the current deployment of treatments with curative intent(liver resection/local ablation and liver transplantation)in early and intermediate stages,a high rate of HCC recurrence persists,underscoring a pivotal clinical challenge.Emergent systemic therapies(ST),particularly immunotherapy,have demonstrate promising outcomes in terms of increase overall survival,but they are currently bound to the advanced stage of HCC.This review provides a comprehensive analysis of the literature,encompassing studies up to March 10,2024,evaluating the impact of novel ST in the early and intermediate HCC stages,specially focusing on the findings of neoadjuvant and adjuvant regimens,aimed at increasing significantly overall survival and recurrence-free survival after a treatment with curative intent.We also investigate the potential role of ST in enhancing the downstaging rate for the intermediate-stage HCC initially deemed ineligible for treatment with curative intent.Finally,we critically discuss about the current relevance of the results of these studies and the encouraging future implications of ST in the treatment schedules of early and intermediate HCC stages. 展开更多
关键词 Hepatocellular carcinoma Early stage Intermediate stage NEOADJUVANT ADJUVANT Systemic therapy
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Lymph node dissection does not affect the survival of patients with tumor node metastasis stages Ⅰ and Ⅱ colorectal cancer 被引量:2
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作者 Fan He Shu-Pei Qu +1 位作者 Ye Yuan Kun Qian 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2503-2510,共8页
BACKGROUND The effect of the number of lymph node dissections(LNDs)during radical resection for colorectal cancer(CRC)on overall survival(OS)remains controver-sial.AIM To investigate the association between the number... BACKGROUND The effect of the number of lymph node dissections(LNDs)during radical resection for colorectal cancer(CRC)on overall survival(OS)remains controver-sial.AIM To investigate the association between the number of LNDs and OS in patients with tumor node metastasis(TNM)stage Ⅰ–Ⅱ CRC undergoing radical resection.METHODS Patients who underwent radical resection for CRC at a single-center hospital between January 2011 and December 2021 were retrospectively analyzed.Cox regression analyses were performed to identify the independent predictors of OS at different T stages.RESULTS A total of 2850 patients who underwent laparoscopic radical resection for CRC were enrolled.At stage T1,age[P<0.01,hazard ratio(HR)=1.075,95%confidence interval(CI):1.019-1.134]and tumour size(P=0.021,HR=3.635,95%CI:1.210-10.917)were independent risk factors for OS.At stage T2,age(P<0.01,HR=1.064,95%CI:1.032-1.098)and overall complications(P=0.012,HR=2.297,95%CI:1.200-4.397)were independent risk factors for OS.At stage T3,only age(P<0.01,HR=1.047,95%CI:1.027-1.066)was an independent risk factor for OS.At stage T4,age(P<0.01,HR=1.057,95%CI:1.039-1.075)and body mass index(P=0.034,HR=0.941,95%CI:0.890-0.995)were independent risk factors for OS.However,there was no association between LNDs and OS in stages Ⅰ and Ⅱ.CONCLUSION The number of LDNs did not affect the survival of patients with TNM stages Ⅰ and Ⅱ CRC.Therefore,insufficient LNDs should not be a cause for alarm during the surgery. 展开更多
关键词 Lymph nodes Colorectal cancer T stage Overall survival Cox regression analyses
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Design,modeling and control of high-bandwidth nano-positioning stages for ultra-precise measurement and manufacturing:a survey 被引量:2
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作者 Wei-Wei Huang Xiangyuan Wang +4 位作者 Yixuan Meng Linlin Li Xinquan Zhang Mingjun Ren Li-Min Zhu 《International Journal of Extreme Manufacturing》 CSCD 2024年第6期204-234,共31页
High-bandwidth nano-positioning stages(NPSs)have boosted the advancement of modern ultra-precise,ultra-fast measurement and manufacturing technologies owing to their fast dynamic response,high stiffness and nanoscale ... High-bandwidth nano-positioning stages(NPSs)have boosted the advancement of modern ultra-precise,ultra-fast measurement and manufacturing technologies owing to their fast dynamic response,high stiffness and nanoscale resolution.However,the nonlinear actuation,lightly damped resonance and multi-axis cross-coupling effect bring significant challenges to the design,modeling and control of high-bandwidth NPSs.Consequently,numerous advanced works have been reported over the past decades to address these challenges.Here,this article provides a comprehensive review of high-bandwidth NPSs,which covers four representative aspects including mechanical design,system modeling,parameters optimization and high-bandwidth motion control.Besides,representative high-bandwidth NPSs applied to atomic force microscope and fast tool servo are highlighted.By providing an extensive overview of the design procedure for high-bandwidth NPSs,this review aims to offer a systemic solution for achieving operation with high speed,high accuracy and high resolution.Furthermore,remaining difficulties along with future developments in this fields are concluded and discussed. 展开更多
关键词 nano-positioning stage high-bandwidth compliant mechanism design dynamics modeling motion control
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Autophagy-dependent ferroptosis may play a critical role in early stages of diabetic retinopathy 被引量:1
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作者 Wen-Jie Sun Xue-Dong An +8 位作者 Yue-Hong Zhang Shan-Shan Tang Yu-Ting Sun Xiao-Min Kang Lin-Lin Jiang Xue-Fei Zhao Qing Gao Hang-Yu Ji Feng-Mei Lian 《World Journal of Diabetes》 SCIE 2024年第11期2189-2202,共14页
Diabetic retinopathy(DR),as one of the most common and significant microvascular complications of diabetes mellitus(DM),continues to elude effective targeted treatment for vision loss despite ongoing enrichment of the... Diabetic retinopathy(DR),as one of the most common and significant microvascular complications of diabetes mellitus(DM),continues to elude effective targeted treatment for vision loss despite ongoing enrichment of the understanding of its pathogenic mechanisms from perspectives such as inflammation and oxidative stress.Recent studies have indicated that characteristic neuroglial degeneration induced by DM occurs before the onset of apparent microvascular lesions.In order to comprehensively grasp the early-stage pathological changes of DR,the retinal neurovascular unit(NVU)will become a crucial focal point for future research into the occurrence and progression of DR.Based on existing evidence,ferroptosis,a form of cell death regulated by processes like ferritinophagy and chaperone-mediated autophagy,mediates apoptosis in retinal NVU components,including pericytes and ganglion cells.Autophagy-dependent ferroptosis-related factors,including BECN1 and FABP4,may serve as both biomarkers for DR occurrence and development and potentially crucial targets for future effective DR treatments.The aforementioned findings present novel perspectives for comprehending the mechanisms underlying the early-stage pathological alterations in DR and open up innovative avenues for investigating supplementary therapeutic strategies. 展开更多
关键词 Diabetic retinopathy Diabetes mellitus Retinal neurovascular unit Autophagy-dependent ferroptosis Early stage Mechanisms
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Novel method for identifying the stages of discharge underwater based on impedance change characteristic
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作者 高崇 康忠健 +3 位作者 龚大建 张扬 王玉芳 孙一鸣 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期133-145,共13页
It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel... It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel underwater discharge stage identification method based on the Strong Tracking Filter(STF) and impedance change characteristics. The time-varying equivalent circuit model of the discharge underwater is established based on the plasma theory analysis of the impedance change characteristics and mechanism of the discharge process. The STF is used to reduce the randomness of the impedance of repeated discharges underwater, and then the universal identification resistance data is obtained. Based on the resistance variation characteristics of the discriminating resistance of the pre-breakdown, main, and oscillatory discharge stages, the threshold values for determining the discharge stage are obtained. These include the threshold values for the resistance variation rate(K) and the moment(t).Experimental and error analysis results demonstrate the efficacy of this innovative method in discharge stage determination, with a maximum mean square deviation of Scrless than 1.761. 展开更多
关键词 discharge underwater discharge stage identification impedance characteristics strong tracking filter
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Nutritional Composition and Distribution of Heracleum dissectum Ledeb.at Different Growth Stages
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作者 Pan Yan Fan Lili +4 位作者 Sun Yan Li Sining Zhuang Yue Sun Haixia Zhong Rongzhen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第3期20-32,共13页
Heracleum dissectum Ledeb.(HD)with high edible and medicinal values is distributed in Northeast Asia.To provide a reference for selecting appropriate parts and periods to harvest HD,the nutrient contents in different ... Heracleum dissectum Ledeb.(HD)with high edible and medicinal values is distributed in Northeast Asia.To provide a reference for selecting appropriate parts and periods to harvest HD,the nutrient contents in different parts of HD at three growth stages were determined.The nutrients being determined are essential nutrients closely related to human needs,and the crude protein content of HD was 3.58‒28.43 g•100 g^(-1)DW(dry weight),sugar content was 2.33‒30.92 g•100 g^(-1)DW,and soluble dietary fiber content was 9.71‒26.09 g•100 g^(-1)DW.Crude protein was mainly distributed in leaf blades and inflorescences,sugar was primarily found in roots,and dietary fiber was predominantly located in leaves.From the leaf development stage to the flowering stage and then to the late seed harvest stage,the content of moisture,crude protein and soluble sugar first decreased and then increased.In contrast,the content of dietary fiber and crude fat first increased and then decreased. 展开更多
关键词 nutrient content VEGETABLE plant organ developmental stage
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Characteristics of Soil Organic Carbon and Total Nitrogen in Rubber Plantations Soil at Different Age Stages in the Western Region of Hainan Island 被引量:17
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作者 吴志祥 谢贵水 +2 位作者 陶忠良 周兆德 王旭 《Agricultural Science & Technology》 CAS 2010年第1期147-153,共7页
[Objective]The aim was to study on the characteristics of soil organic carbon and nitrogen in rubber (Hevea brasiliensis Muell-Arg) plantations at different age stages in the western region of Hainan Island,so as to... [Objective]The aim was to study on the characteristics of soil organic carbon and nitrogen in rubber (Hevea brasiliensis Muell-Arg) plantations at different age stages in the western region of Hainan Island,so as to evaluate the ecological benefits of rubber plantations and provide basic data for studying the effect of tropical land utilization/cover change on the global carbon and nitrogen cycle. [Method]The situs was in Danzhou city,western region of Hainan Island,and the samples were four kinds of rubber plantations soil at different ages and one kind of control check (pepper,Piper nigrum L.) soil. In this research,four quadrats were set up in each sample,and the size of each was 20 cm×20 cm. Four specimens were gathered from four layers of 0-15,15-30,30-45,45-60,and the average of them was the last analysis result of each sample. Soil density was measured by cutting ring method,soil containing and hygroscopic water was detected by oven drying method,soil organic carbon (SOC) was measured by low temperature heated outside potassium dichromate oxidation-colorimetry method,and soil total nitrogen (STN) was detected by semimicro Kjeldahl method. [Result]SOC contents of different layers in rubber plantations soil at different age stages (including the CK pepper soil,the same as below) varied little,and the content of SOC in surface layer (0-15 cm) was higher,while the underlayer (45-60 cm) was lower than the average value; there was significant difference in SOC content among different kinds of soil,and the content was of 6.03-7.78 g/kg,tapping young trees (7 years) CK pepper mature age trees (30 years) prophase of young trees (2 years) tapping trees (16 years); there was no significant difference in SOC storage among different kinds of soil,and the storage was of 61.33-74.29 t/hm2,mature age trees (30 years) tapping young trees (7 years) prophase of young trees (2 years) CK pepper tapping trees (16 years); there was significant difference in STN content among rubber plantations soil at different age stages,the content was of 410.86-664.14 mg/kg2,CK pepper tapping young trees (7 years) prophase of young trees (2 years) mature age trees (30 years) tapping trees (16 years),and STN content of tapping trees (16 years) soil was extremely lowest; there was significant difference in C/N ratio among different kinds of soil,the ratio was of 10.94-14.47,and the ratio of tapping trees (16 years) mature age trees (30 years) tapping young trees (7 years) CK pepper prophase of young trees (2 years). [Conclusion]There wasn't unhealthy effect of rubber trees planted in tropical area on the content and storage of SOC,the content of STN and the ratio of C/N. there was no significant difference between rubber plantations and CK pepper soil,and the effects of rubber plantation on soil carbon-nitrogen was similar to that of other tropical crops (such as pepper). 展开更多
关键词 Different age stages of trees Rubber (Hevea brasiliensis) plantations Soil organic carbon (SOC) Soil total nitrogen (STN) Hainan Island
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Effects of Short-term High Temperature Stress on the Photosynthesis of Potato in Different Growth Stages 被引量:3
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作者 王连喜 金鑫 +3 位作者 李剑萍 马国飞 曹宁 李琪 《Agricultural Science & Technology》 CAS 2011年第3期317-321,342,共6页
[Objective] The aim was to study the effects of short-term high temperature stress on the photosynthesis of potato in different growth stages. [Method] Choosing powder potato named Longshu No.3 widely cultivated in Ni... [Objective] The aim was to study the effects of short-term high temperature stress on the photosynthesis of potato in different growth stages. [Method] Choosing powder potato named Longshu No.3 widely cultivated in Ningxia as test material,the changes of stomata conductance (Gs),transpiration rate (Tr) and CO2 concentration difference between internal and external leaf chamber,net photosynthetic rate (Pn) and photosynthetic water use efficiency (WUE) in different growth stages under short-term high temperature were analyzed. [Result] During seedling stage,the hysteretic nature of net photosynthetic rate and CO2 concentration difference between internal and external leaf chamber of potato could be found under high temperature stress,while the change trends of stomata conductance and transpiration rate under high temperature stress were consistent to that at normal temperature,but stomata conductance and transpiration rate were higher than those at normal temperature,and CO2 concentration difference between internal and external leaf chamber affected net photosynthetic rate most obviously. During branching stage,the change trends of net photosynthetic rate,CO2 concentration difference between internal and external leaf chamber,stomata conductance and transpiration rate under high temperature stress and normal temperature were similar,but they changed abruptly and reached peak value at noon under high temperature stress,while there existed consistent variation of water use efficiency under high temperature stress and at normal temperature,and CO2 concentration difference between internal and external leaf chamber also affected net photosynthetic rate most greatly,next came transpiration rate. [Conclusion] High temperature stress affected the photosynthesis of potato in different growth stages,and it was more obvious during branching stage than seedling stage,while CO2 concentration difference between internal and external leaf chamber had the most important influence on net photosynthetic rate. 展开更多
关键词 POTATO Different growth stages High temperature stress PHOTOSYNTHESIS
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Effects of Waterlogging in Different Growth Stages on Nitrogen Uptake, Distribution, and Utilization of Cotton 被引量:1
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作者 杨富强 刘瑞显 +1 位作者 张国伟 杨长琴 《Agricultural Science & Technology》 CAS 2014年第9期1503-1507,共5页
[Objective] This study aimed to investigate the effects of waterlogging in different growth stages on nitrogen (N) uptake, distribution, and utilization of cotton. [Method] A pool-culture experiment in field was con... [Objective] This study aimed to investigate the effects of waterlogging in different growth stages on nitrogen (N) uptake, distribution, and utilization of cotton. [Method] A pool-culture experiment in field was conducted to investigate the effects of wateriogging through comparing WL1 (waterlogging at peak squaring stage) and WL2 (waterlogging at flowering and boll-forming stage) treatments with their controls respectively. [Result] The results showed that the effect of WL1 on N uptake of cotton root was stronger than WL2. At 20 days (d) after WL1 treatment, the root biomass (RB), N uptake (NU), and N uptake rate (NUR) significantly decreased by 38.1%, 48.6%, and 53.0% respectively. At 20 d after WL2 treatment, the RB, NU, and NUR significantly decreased by 27.3%, 46.0%, and 44.8% respectively. More N was distributed to root and leaf after WL1 treatment, and to square, flower, and boll after WL2 treatment. N physiological use efficiency increased by 11.4% and 44.4% after WL1 and WL2 treatments respectively. Further analysis showed that the effects of WL1 on yield and its components of cotton were stronger than WL2. The boll number, boll weight, and lint yield per plant significantly reduced by 40.5%, 12.4%, and 49.5% after WL1 treatment, and significantly decreased by 23.1%, 6.9%, and 29.9% after WL2 treatment, respectively. [Conclusion] The negative effects of water- logging at peak squaring stage on N nutrition and yield of cotton were stronger than waterlogging at flowering and boll-forming stage, indicating that more attention should be paid to waterlogging at peak squaring stage and sound N management can improve cotton regrowth and reduce yield loss after waterlogging. 展开更多
关键词 Growth stages WATERLOGGING COTTON NITROGEN
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