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Comprehensive Analysis of the Relative Dispersion of Droplet-Size Distributions and Their Relationships to Key Physical Fog Processes Under Different Aerosol Conditions and Evolutionary Stages
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作者 Xingcan JIA Chunsong LU +7 位作者 Zhiheng LIAO Ping TIAN Yuan WANG Fei WANG Shuai YANG Youjun DOU Xiange LIU Yangang LIU 《Advances in Atmospheric Sciences》 2026年第4期861-873,I0042-I0046,共18页
The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with... The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with limited studies on fog,particularly those that examine the combined influences of all key physical processes and their roles during fog evolution.As such,this study aims to conduct a comprehensive investigation by examining the relationships between relative dispersion and other microphysical variables,as well as the underlying microphysical and dynamic processes,based on field fog campaigns in polluted and clean conditions.In polluted fog,droplet concentrations are higher,leading to smaller droplets and increased dispersion.The correlation between dispersion and droplet volume-mean radius is positive in the polluted fog,but shifts to negative in clean fog.We attribute the difference to various microphysical processes like aerosol activation,condensation,collision-coalescence,and entrainment-mixing.In polluted fog,high aerosol concentrations,low supersaturations,and strong turbulence(entrainment-mixing)provide suitable conditions for the simultaneous occurrence of droplet condensation and aerosol activation,resulting in a positive correlation between dispersion and volume-mean radius,especially during the fog formation stage.In contrast,during the mature stage in clean fog,condensation is dominant with weak aerosol activation leading to a negative correlation between relative dispersion and volume-mean radius.The collision-coalescence process is more active in the mature stage,increasing radii and leading to the negative correlation between dispersion and volume-mean radius.This result sheds new light on understanding the relative dispersion and mechanisms in fog under different aerosol backgrounds. 展开更多
关键词 FOG relative dispersion evolutionary stage aerosol activation collision-coalescence
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Strategies of allocating root-shoot biomass in plantations and natural forests at various community stages and moisture levels
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作者 Wenjing Chen Lei Liu +3 位作者 Josep Penuelas Guoyi Zhou Langqin Hua Zhurong Wu 《Journal of Forestry Research》 2026年第2期85-99,共15页
The root-to-shoot(R/S)ratio is a critical indicator of the balance between root biomass and shoot biomass,representing the ecological strategies and adaptive responses of plants to environmental conditions.However,the... The root-to-shoot(R/S)ratio is a critical indicator of the balance between root biomass and shoot biomass,representing the ecological strategies and adaptive responses of plants to environmental conditions.However,the patterns of change in community R/S ratios during forest succession and their response to moisture levels across broad geographic gradients remains unclear.Based on forest biomass data from a national field inventory of 5,825 plots conducted across China between 2011 and 2015,this study looked into allocating biomass shoots and roots at the early,middle,and late stages of growth in plantations and succession in natural forests,and evaluated how moisture availability influences this allocation.The results revealed a significant decline in R/S ratios from early to late stages for both plantations and natural forests.Shoot and root biomass in plantations grew isometrically during the early and middle succession stages but shifted to allometric growth in the late stage,with the slope of the log-transformed shoot-root biomass relationship differing significantly across growth stages.Natural forests,in contrast,maintained isometric growth across successional stages,showing no significant variation in the slope of the log-transformed shoot-root biomass relationship.Environmental factors,particularly moisture levels,strongly influenced R/S ratios.Moisture levels significantly affected size-corrected R/S ratios,particularly in the middle stage of plantations and the early and middle stages of natural forests,supporting the hypothesis of optimal allocation.These findings suggest that in water-limited regions,forest management should prioritize drought-tolerant,deep-rooted native species,encourage mixed-species planting in the early stage,and reduce logging intensity in mature plantations.Conserving natural forests to maintain successional dynamics is essential for long-term ecological resilience.These findings emphasize the importance of balancing productivity with ecological sustainability by adapting practices to specific environments and forest types under climate change. 展开更多
关键词 Root-to-shoot ratios Biomass allocation Forest type Community stage Moisture levels Allometric scaling
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Shifting focus to preclinical stages:Locus coeruleus tau pathology as a driver and therapeutic target in Alzheimer’s disease
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作者 Qi Yuan Tamunotonye Omoluabi Brandon F.Hannam 《Neural Regeneration Research》 2026年第6期2335-2336,共2页
Alzheimer’s disease(AD)remains an incurable neurodegenerative disorder with devastating societal and personal impacts.Despite decades of intensive research,therapeutic efforts targeting the clinical stages of AD have... Alzheimer’s disease(AD)remains an incurable neurodegenerative disorder with devastating societal and personal impacts.Despite decades of intensive research,therapeutic efforts targeting the clinical stages of AD have largely failed to halt or reverse disease progression.This has prompted a critical shift in focus toward the earlier,preclinical stages of AD,where interventions may hold greater promise for altering the disease trajectory. 展开更多
关键词 alzheimer s disease ad remains therapeutic target Alzheimers disease neurodegenerative disorder preclinical stages locus coeruleus tau pathology
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The Growing Stages of Peanuts
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作者 赵鑫阳 《疯狂英语(双语世界)》 2025年第3期60-62,共3页
Peanuts are widely produced and commonly eaten in China.They grow well in warm climates with moderate rainfall and sandy soil,and they have a relatively long growing season.In China,the main peanut-producing areas are... Peanuts are widely produced and commonly eaten in China.They grow well in warm climates with moderate rainfall and sandy soil,and they have a relatively long growing season.In China,the main peanut-producing areas are Henan,Shandong,and Hebei provinces.From planting to harvest,peanuts go through five main stages. 展开更多
关键词 hebei provinces china SHANDONG HENAN growing stages peanuts
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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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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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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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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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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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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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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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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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A Retrospective Real-World Study:The Efficacy and Safety of Immune Checkpoint Inhibitors Combined with Chemoradiotherapy in Limited-Stage Small Cell Lung Cancer
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作者 Ruoxue Cai Shuyi Hu +3 位作者 Feiyang Li Huanhuan Sha Guoren Zhou Ying Fang 《Oncology Research》 2026年第2期473-485,共13页
Objective:To determine whether immunotherapy can bring new hope for patients with limited-stage small-cell lung cancer(LS-SCLC).We conducted this retrospective study to evaluate whether immunotherapy can achieve bette... Objective:To determine whether immunotherapy can bring new hope for patients with limited-stage small-cell lung cancer(LS-SCLC).We conducted this retrospective study to evaluate whether immunotherapy can achieve better efficacy in LS-SCLC patients.Methods:We evaluated 122 LS-SCLC patients who received concurrent chemoradiotherapy(CCRT)or sequential chemoradiotherapy(SCRT)(Group A)and immunotherapy combined with CCRT/SCRT followed by immunotherapy(Group B),to assess the objective response rate(ORR),disease control rate(DCR),and progression-free survival(PFS).Factors affecting prognosis were also explored using Cox analysis.The prognosis of patients with type 2 diabetes and patients with different TNM stages was compared to guide the selection of clinical regimens.Results:The overall ORR was 55.93%.The overall DCR was 98.31%.The DCR was 100%in Group A and 96.61%in Group B.There was no statistical difference in ORR and DCR.The overall median PFS was 9.86 months(95%CI,8.62-11.10),and the difference in median PFS between the two groups was statistically significant(8.94 vs.11.89 months,p=0.03).The Cox regression analysis showed type 2 diabetes was associated with the survival prognosis.Patients with type 2 diabetes tended to choose immunotherapy combined with CCRT/SCRT.Patients in TNM stage IIIB had a significantly worse prognosis than those in stage I+II+IIIA.Conclusion:We suggest that LS-SCLC patients who receive immunotherapy combined with CCRT/SCRT can achieve longer PFS than those with CCRT/SCRT.Type 2 diabetes and TNM stage affect the survival prognosis.Patients with type 2 diabetes may benefit from immunotherapy combination treatments. 展开更多
关键词 Limited-stage small cell lung cancer immunotherapy CHEMORADIOTHERAPY TNM stage type 2 diabetes
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Laparoscopic liver resection is superior to open liver resection for hepatocellular carcinoma patients with BCLC stage 0-A hepatocellular carcinoma and portal hypertension
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作者 Wu-Gui Yang Bin Liang +5 位作者 Yu-Fu Peng Yu-Bo Yang Ya-Ni Liu Bo Li Yong-Gang Wei Fei Liu 《Hepatobiliary & Pancreatic Diseases International》 2026年第1期32-41,共10页
Background:According to the 2022 update of the BCLC strategy,laparoscopic liver resection(LLR)is considered feasible for BCLC stage 0-A hepatocellular carcinoma(HCC)patients with clinically significant portal hyperten... Background:According to the 2022 update of the BCLC strategy,laparoscopic liver resection(LLR)is considered feasible for BCLC stage 0-A hepatocellular carcinoma(HCC)patients with clinically significant portal hypertension(CSPH).However,there is still no research to explore the outcomes of laparoscopic versus open liver resection(OLR)in the specific patients with BCLC stage 0-A HCC and CSPH.Methods:Patients diagnosed with BCLC stage 0-A HCC and CSPH who underwent liver resection at West China Hospital of Sichuan University from February 2018 to December 2022 were analyzed.Demographic characteristics,pathological findings and postoperative outcomes were compared using propensity score matching(PSM).Long-term outcomes after surgery were analyzed using Kaplan-Meier analysis both before and after PSM.Results:A total of 409 patients,including 261 LLRs and 148 OLRs,were enrolled in this study.There were imbalances between the groups in baseline information.After 1:1 PSM,118 patients were included in each group with comparable baseline characteristics.Patients in the LLR group had significantly less intraoperative blood loss compared to those in the OLR group(median 223 vs.318 mL,P<0.001),and fewer postoperative complications(33.9%vs.57.6%,P<0.001),including lower rates of postoperative liver decompensation(16.9%vs.28.0%,P=0.043),postoperative ascites(18.6%vs.31.4%,P=0.024)and pulmonary infections(12.7%vs.29.7%,P=0.001).The long-term follow-up showed that overall survival(P=0.154)and recurrence-free survival(P=0.376)were comparable between the two groups.In subgroup analysis,patients with PLT≤75×10^(9)/L suffered more postoperative liver decompensation(PLD)and ascites than patiens with PLT>75×10^(9)/L.Conclusions:Compared with OLR,LLR had less intraoperative blood loss,fewer postoperative complications and comparable oncological outcomes for patients with BCLC stage 0/A HCC and CSPH. 展开更多
关键词 Laparoscopic liver resection Hepatocellular carcinoma Clinically significant portal hypertension BCLC stage
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Influence of Phenological Stage on the Volatile Content and Biological Properties of Origanum elongatum Essential Oil
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作者 Amine Batbat Khaoula Habbadi +6 位作者 Mohamed Jeddi Samiah Hamad Al-Mijalli Hanae Naceiri Mrabti Fahad M.Alshabrmi Naif Hesham Moursi Hassane Greche Naoufal El Hachlafi 《Phyton-International Journal of Experimental Botany》 2026年第1期203-217,共15页
Origanum elongatum(OE)is an aromatic,medicinal plant endemic to Morocco that is widely used in traditional medicine due to its biological properties.This study aimed to elucidate the chemical composition of the essent... Origanum elongatum(OE)is an aromatic,medicinal plant endemic to Morocco that is widely used in traditional medicine due to its biological properties.This study aimed to elucidate the chemical composition of the essential oil(EO)obtained from O.elongatum(OEEO)at three stages of its life cycle,including vegetative stage(OEEO-VS),flowering stage(OEEO-FS),and post-flowering(OEEO-PFS),as well as to evaluate its biological and antiradical characteristics.The chemical analysis of the essential oil was conducted using gas chromatography-mass spectrometry(GC-MS).The antibacterial activity was evaluated in vitro through distinct methodologies,namely,disc diffusion and microatmosphere assay;subsequently,the minimum inhibitory concentration(MIC)was then determined.The antioxidant potential was also measured by using the DPPH and FRAP assays.The GC-MS revealed the predominant of p-cymene(26.83%_31.45%),γ-terpinene(8.46%_26.95%),thymol(13%_29.54%),and carvacrol(20.25%_37.26%),in all three samples,with notable variations according to the phenological stage of the samples.The EOs extracted at three phenological stages demonstrated notable antibacterial efficacy against all the phytopathogen tested.The MICs for Erwinia amylovora exhibited a range of 6.25 and 250μg/mL.However,for Agrobacterium tumefaciens C58 and Allorhizobium vitis S4,the MICs spanned 125 and 250μg/mL.In the DPPH test,the IC50 values were 168.25±1.14,147.01±0.78,and 132.01±2.06μg/mL for EOs derived from the vegetative,flowering,and post-flowering period,respectively.In the FRAP test,the EC50 values were 164.22±1.04,215.73±1.48,and 184.06±0.95μg/mL for the same stages.The findings offer promising prospects for the phytochemical development,demonstrating how the phenological stage significantly influences the therapeutic and biotechnological potential of O.elongatum.This has the potential to open up new avenues of research in the pharmaceutical,agronomic,and environmental fields. 展开更多
关键词 Origanum elongatum phenological stage chemical composition antioxidant activity antibacterial activity bioactive compounds plant development chemotype variation
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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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Comparison on the therapeutic effect of acupuncture on 60 cases of peripheral facial paralysis at different stages 被引量:5
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作者 张东云 宋海云 ZHOU Shang-tong 《World Journal of Acupuncture-Moxibustion》 2013年第4期11-14,18,共5页
Objective To investigate the difference in the therapeutic effect of different methods in the treatment of peripheral facial paralysis (PFP) at different stages. Methods Sixty cases of PFP at different stages were d... Objective To investigate the difference in the therapeutic effect of different methods in the treatment of peripheral facial paralysis (PFP) at different stages. Methods Sixty cases of PFP at different stages were divided into a treatment group and a control group according to the sequence for visit, and 30 patients were included in each group. The patients in the treatment group were treated by using drugs, acupuncture (shallow puncture and subexcite) and microwave therapy during the acute stage, and they were subjected to electroacupuncture (EA) (heavy stimulation and penetration needling), acupoint injection, electrotherapy and massage during the convalescence stage. In contrast, the patients in the control group were treated simply with drugs, and the therapeutic methods during the convalescence stage were the same to those for the treatment group, and the therapeutic effect of the two groups was observed after three treatment courses. Results The total effective rate in the treatment group was 100.0% (30/30), the cured rate after one treatment course was 48.2% (13/27), the cured rate after two treatment courses was 44.4% (12/27), and the cured rate after three treatment courses was 7.4% (2/27). The total effective rate in the control group was 90.0% (27/30), the cured rate after one treatment course was 5.5% (1/18), the cured rate after two treatment courses was 27.8% (5/18), and the cured rate after three treatment courses was 66.7% (12/18). The therapeutic effect and the treatment courses for healing of the treatment group were significantly better than those in the control group (P0.05). Conclusion the therapeutic effect of different therapeutic methods on PFP is remarkable. 展开更多
关键词 peripheral facial paralysis (PFP) STAGING ACUPUNCTURE therapeutic program
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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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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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Histologic Classification of Thymoma and Its Relationship with Myasthenia Gravis and Clinical Stages of the Tumor 被引量:1
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作者 王新允 陈云新 +1 位作者 王爱香 张淑敏 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第5期314-316,327,共4页
Objective: To investigate the relationship among the latest WHO classification of thymoma, myasthenia gravis (MG) and clinical stages. Methods: To review the pathological sections of 74 patients with thymoma from ... Objective: To investigate the relationship among the latest WHO classification of thymoma, myasthenia gravis (MG) and clinical stages. Methods: To review the pathological sections of 74 patients with thymoma from 1980-2004 using WHO classification (1999), the statistical software was used to analyze the relationship among the WHO classification, MG and clinical stages. Results: (1) Two cases of type A, 23 cases of type AB, 4 cases of type B1, 27 cases of type B2, 16 cases of type B3 and 2 cases of type C were classified. Type B2 more likely accompanied MG (P〈0.05), while none with MG occurred for type C. (2) One patient was in stage Ⅰ, 30 were in stage Ⅱ, 38 were in stage Ⅲ, and 5 were in stage Ⅳ. The latest histologic classification was significantly correlated with Masaoka stages (P〈0.01). Conclusion: The latest WHO classification was correlated with occurrence of MG and finely reflected clinical stage. It can also evaluate the prognosis of patients. 展开更多
关键词 THYMOMA myasthenia gravis clinical stages
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