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Splitting of Operations for Di-Associative Algebras and Tri-Associative Algebras
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作者 Wen TENG Xiansheng DAI 《Journal of Mathematical Research with Applications》 2026年第1期21-32,共12页
Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algeb... Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras. 展开更多
关键词 dendriform algebra di-associative algebra quad-dendriform algebra tri-associative algebra six-dendriform algebra relative averaging operator
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Melatonin and mitochondrial stress: New insights into age-related neurodegeneration
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作者 Silvia Carloni Francesca Luchetti +3 位作者 Maria Gemma Nasoni Walter Balduini Walter Manucha Russel J.Reiter 《Neural Regeneration Research》 2026年第4期1564-1565,共2页
Aging,mitochondria,and neurodegenerative diseases:Aging is often viewed as the buildup of changes that lead to the gradual transformations associated with getting older,along with a rising likelihood of disease and mo... Aging,mitochondria,and neurodegenerative diseases:Aging is often viewed as the buildup of changes that lead to the gradual transformations associated with getting older,along with a rising likelihood of disease and mortality.Although organis m-wide deterioration is observed during aging,organs with high metabolic demand,such as the brain,are more vulnerable. 展开更多
关键词 buildup changes neurodegenerative diseases aging neurodegenerative diseases MITOCHONDRIA mitochondrial stress MELATONIN age related neurodegeneration AGING
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Hemoperitoneum from omental variceal bleed resulting in first documented successful liver transplant:A case report
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作者 Emily E Currier Cindy Y Won +2 位作者 Ximena Parraga Karen S Lee Behnam Saberi 《World Journal of Transplantation》 2026年第1期249-255,共7页
BACKGROUND While varices and variceal bleeds are well-known and feared complications of advanced cirrhosis and portal hypertension,omental variceal bleed are a rare sequala even in patients with known esophageal or ga... BACKGROUND While varices and variceal bleeds are well-known and feared complications of advanced cirrhosis and portal hypertension,omental variceal bleed are a rare sequala even in patients with known esophageal or gastric varices.While rare,omental varices pose a risk for hemoperitoneum if ruptured,which is a lifethreatening complication with high mortality rates despite surgical intervention.CASE SUMMARY This report reviews the case of a patient 36-year-old female with alcohol related cirrhosis decompensated by ascites,but no history of varices admitted for hemorrhagic shock from spontaneous rupture of omental varices requiring emergency surgery.She underwent the first documented successful orthotopic liver transplantation the same admission.CONCLUSION This case report and literature review stresses the importance of early consideration and identification of intraabdominal variceal sources in cirrhotic patients with refractory shock. 展开更多
关键词 Omental varices Alcoholic liver disease Alcohol related cirrhosis Variceal bleed Orthotropic liver transplant HEMOPERITONEUM Omental variceal bleed Case report
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Autophagy-targeting modulation to promote peripheral nerve regeneration 被引量:3
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作者 Yan Chen Hongxia Deng Nannan Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第7期1864-1882,共19页
Nerve regeneration following traumatic peripheral nerve injuries and neuropathies is a complex process modulated by diverse factors and intricate molecular mechanisms.Past studies have focused on factors that stimulat... Nerve regeneration following traumatic peripheral nerve injuries and neuropathies is a complex process modulated by diverse factors and intricate molecular mechanisms.Past studies have focused on factors that stimulate axonal outgrowth and myelin regeneration.However,recent studies have highlighted the pivotal role of autophagy in peripheral nerve regeneration,particularly in the context of traumatic injuries.Consequently,autophagy-targeting modulation has emerged as a promising therapeutic approach to enhancing peripheral nerve regeneration.Our current understanding suggests that activating autophagy facilitates the rapid clearance of damaged axons and myelin sheaths,thereby enhancing neuronal survival and mitigating injury-induced oxidative stress and inflammation.These actions collectively contribute to creating a favorable microenvironment for structural and functional nerve regeneration.A range of autophagyinducing drugs and interventions have demonstrated beneficial effects in alleviating peripheral neuropathy and promoting nerve regeneration in preclinical models of traumatic peripheral nerve injuries.This review delves into the regulation of autophagy in cell types involved in peripheral nerve regeneration,summarizing the potential drugs and interventions that can be harnessed to promote this process.We hope that our review will offer novel insights and perspectives on the exploitation of autophagy pathways in the treatment of peripheral nerve injuries and neuropathies. 展开更多
关键词 AUTOPHAGY autophagy related genes Charcot–Marie–Tooth diseases diabetic peripheral neuropathy METFORMIN MYELINATION peripheral nerve injury Schwann cells sciatic nerve Wallerian degeneration
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Hypidone hydrochloride(YL-0919)ameliorates functional deficits after traumatic brain injury in mice by activating the sigma-1 receptor for antioxidation 被引量:2
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作者 Yafan Bai Hui Ma +5 位作者 Yue Zhang Jinfeng Li Xiaojuan Hou Yixin Yang Guyan Wang Yunfeng Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2325-2336,共12页
Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0... Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury. 展开更多
关键词 antidepressant drug blood-brain barrier cognitive function hypidone hydrochloride(YL-0919) neurological function nuclear factor-erythroid 2 related factor 2 oxidative stress sigma-1 receptor superoxide dismutase traumatic brain injury
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Coupling and Spatial Disparities of Regional Economy and Ecosystem in High-Quality Town Development 被引量:2
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作者 Xinyi Ren Xiaowen Tan +2 位作者 Dan Luo Rongxin Lu Chien-Chi Chu 《Research in Ecology》 2025年第1期15-29,共15页
This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expan... This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expansion with environmental protection,a comprehensive evaluation index system is constructed,encompassing two key dimensions:regional economy and ecological environment.Using panel data from 2013 to 2022,the coupling coordination degree model is employed to quantify the interactions and synergy between these dimensions.Additionally,spatial econometric methods are applied to calculate both global and local Moran’s Index,revealing spatial clustering patterns,regional disparities,and heterogeneity.The relative development model further identifies critical factors influencing regional coordination,with a focus on the lagging development of basic infrastructure and public services.The findings demonstrate a positive temporal trend toward improved regional coordination and reduced development gaps,with a spatial pattern characterized by higher coupling degrees in eastern and central regions compared to western areas.Based on these results,this study proposes actionable strategies to enhance coordinated development,emphasizing ecological conservation,the establishment of green production and consumption systems,ecological restoration,and strengthened municipal collaboration.This revised abstract emphasizes the study’s purpose,methods,and key findings more clearly while maintaining a professional and concise tone.Finally,based on the above analysis results,the corresponding coordinated development suggestions of regional economy and ecological environment are given from the aspects of ecological environment protection measures,green production and consumption system construction,ecological environment restoration and municipal coordination. 展开更多
关键词 Regional Economies Ecological Environment Coupling Coordination Degree Spatiotemporal Distribution Characteristics Relative Development Model
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Factors Influencing the Efficacy of Chinese Medicinals 被引量:1
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作者 Qichao Liang Yun Jiang +1 位作者 Liguo Liang Hualong Liang 《Chinese Medicine and Natural Products》 2025年第2期73-85,共13页
This paper thoroughly explores the multifaceted factors influencing the efficacy of Chinese medicinals and categorizes them into three main groups:medicinal related factors,patient related factors,and practitioner rel... This paper thoroughly explores the multifaceted factors influencing the efficacy of Chinese medicinals and categorizes them into three main groups:medicinal related factors,patient related factors,and practitioner related factors.Regarding medicinal related factors,the place of origin,growing environment,harvesting time,storage conditions,quality control,dosage form selection,compatibility of medicinals,precise dosing,decoction methods,and administration routes all significantly impact efficacy.The place of origin determines the authenticity of medicinals,the growing environment affects their composition,harvesting time influences potency,improper storage leads to deterioration,quality control forms the foundation of efficacy,dosage forms and compatibility of medicinals affect absorption,dosing and decoction methods require precision,and administration routes should be tailored to individuals.Patient related factors include psychological state,individual differences,background,and disease condition.Psychological state affects treatment compliance,individual differences determine medicine responses,background influences patients’understanding of Chinese medicinals,and disease condition directly reflects efficacy.Practitioner related factors encompass theoretical knowledge,clinical experience,inherited practices,psychological state,and professional ethics.Theoretical knowledge guides medication use,clinical experience enhances efficacy,inherited practices influence prescribing styles,psychological state affects doctor–patient communication,and professional ethics ensure medical quality.These interrelated factors collectively influence the efficacy of Chinese medicinals,emphasizing the need for comprehensive consideration in clinical applications to achieve optimal therapeutic outcomes. 展开更多
关键词 Chinese medicinals efficacy of Chinese medicinals influencing factors medicinal related factors patient related factors practitioner related factors authentic medicinal materials
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Five-year conditional relative survival up to 10 years post-diagnosis among adolescent and young adult breast cancer patients by age,stage,and receptor subtype 被引量:1
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作者 Noëlle J.M.C.Vrancken Peeters Daniël J.van der Meer +5 位作者 Marleen Kok Marissa C.van Maaren Marie-Jeanne T.F.D.Vrancken Peeters Sabine Siesling Winette T.A.van der Graaf Olga Husson 《Journal of the National Cancer Center》 2025年第3期297-305,共9页
Background Conditional relative survival(CRS),the probability of survival given that an individual has already survived a certain period post-diagnosis,is a more clinically relevant measure for long-term survival than... Background Conditional relative survival(CRS),the probability of survival given that an individual has already survived a certain period post-diagnosis,is a more clinically relevant measure for long-term survival than standard relative survival(RS).This study aims to evaluate the 5-year CRS among adolescent and young adult(AYA)breast cancer patients by age,tumor stage,and receptor subtype to guide disclosure periods for insurance.Methods Data of all females aged 18–39 years and diagnosed with invasive breast cancer between 2003 and 2021(n=13,075)were obtained from The Netherlands Cancer Registry(NCR).The five-year CRS was calculated annually up to 10 years post-diagnosis using a hybrid analysis approach.Results For the total AYA breast cancer study population the 5-year CRS exceeded 90%from diagnosis and increased beyond 95%7 years post-diagnosis.Patients aged 18–24 reached 95%9 years post-diagnosis,those aged 25–29 after 5 years,and those aged 30–34 and 35–39 after 8 years.For stage I,the 5-year CRS reached 95%from diagnosis,for stage II after 6 years,while the 5-year CRS for stages III and IV did not reach the 95%threshold during the 10-year follow-up.Triple-negative tumors exceeded 95%after 4 years,human epidermal growth factor receptor 2(HER2)positive tumors after 6 years,while hormone receptor(HR)positive tumors did not reach 95%.Conclusion Excess mortality among AYA breast cancer patients tends to be little(CRS 90%–95%)from diagnosis and becomes minimal(CRS>95%)over time compared to the general population.These results can enhance expectation management and inform policymakers,suggesting a shorter disclosure period. 展开更多
关键词 Adolescents and young adults(AYAS) Breast cancer Conditional relative survival(CRS) Excess mortality Relative survival(RS) SURVIVORSHIP
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Seasonal population trend and relative occurrence of pests and their natural enemies among cotton species and cultivars in India 被引量:1
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作者 NAGRARE V.S. NAIKWADI Bhausaheb +4 位作者 FAND Babasaheb B. NAIK V.Chinna Babu TENGURI Prabhulinga GOKTE‑NARKHEDKAR Nandini WAGHMARE V.N. 《Journal of Cotton Research》 2025年第2期178-192,共15页
Background Cotton crop is infested by numerous arthropod pests from sowing to harvesting,causing substantial direct and indirect yield losses.Knowledge of seasonal population trends and the relative occurrence of pest... Background Cotton crop is infested by numerous arthropod pests from sowing to harvesting,causing substantial direct and indirect yield losses.Knowledge of seasonal population trends and the relative occurrence of pests and their natural enemies is required to minimize the pest population and yield losses.In the current study,analysis of the seasonal population trend of pests and natural enemies and their relative occurrence on cultivars of three cotton species in Central India has been carried out.Results A higher number and diversity of sucking pests were observed during the vegetative cotton growth stage(60 days after sowing),declining as the crop matured.With the exception of cotton jassid(Amrasca biguttula biguttula Ishida),which caused significant crop damage mainly from August to September;populations of other sucking insects seldom reached economic threshold levels(ETL)throughout the studied period.The bollworm complex populations were minimal,except for the pink bollworm(Pectinophora gossypiella Saunders),which re-emerged as a menace to cotton crops during the cotton cropping season 2017–2018 due to resistance development against Bt-cotton.A reasonably good number of predatory arthropods,including coccinellids,lacewings,and spiders,were found actively preying on the arthropod pest complex of the cotton crop during the early vegetative growth stage.Linear regression indicates a significant relationship between green boll infestations and pink bollworm moths in pheromone traps.Multiple linear regression analyse showed mean weekly weather at one-or two-week lag periods had a significant impact on sucking pest population(cotton aphid,cotton jassid,cotton whitefly,and onion thrips)fluctuation.Gossypium hirsutum cultivars RCH 2 and DCH 32,and G.barbadense cultivar Suvin were found susceptible to cotton jassid and onion thrips.Phule Dhanvantary,an G.arboreum cotton cultivar,demonstrated the highest tolerance among all evaluated cultivars against all sucking pests.Conclusion These findings have important implications for pest management in cotton crops.Susceptible cultivars warrant more attention for plant protection measures,making them more input-intensive.The choice of appropriate cultivars can help minimize input costs,thereby increasing net returns for cotton farmers. 展开更多
关键词 COTTON PESTS Population trend Relative occurrence CULTIVARS Natural enemies
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Distribution,species richness,and relative importance of different plant life forms across drylands in China 被引量:1
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 DRYLANDS Environmental gradients Plant life forms Relative importance Species richness THRESHOLD
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Effective implementation of controlled blasting methodology during excavation of hard rock in the close proximity of earthen dam and tunnel 被引量:1
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作者 Prakash K.Palei Vijay K.Ghodake +5 位作者 S.Santhosh Kumar R.S.Gurjar Chaman Singh M.Meena Rizwan Ali R.S.Kankara 《Defence Technology(防务技术)》 2025年第6期306-316,共11页
The present technical paper outlines the details of the controlled blasting techniques used to optimize blasting pattern for excavation of hard rock near the Bhira Earthen Dam in Maharashtra,India.In this connection,a... The present technical paper outlines the details of the controlled blasting techniques used to optimize blasting pattern for excavation of hard rock near the Bhira Earthen Dam in Maharashtra,India.In this connection,a series of experimental blasts were conducted by adjusting various blast design parameters at project site.The safe charge weight per delay was kept between 0.125 and 0.375 kg.The outcomes of these experimental blasts were analyzed to recommend optimized blasting patterns and methods for the overall excavation process during actual blasting operations.Blast design parameters,including the maximum quantity of explosive per delay,hole depth,burden and spacing between holes were optimized by using a site-specific attenuation equation,taking into account the proximity of the dam and tunnel from the blasting area.Peak particle velocity(PPV)level of 10 mm/s and 50 mm/s respectively were adopted as the safe vibration level for ensuring safety of the Bhira Earthen Dam and the nearby tunnel from the adverse effects of blast vibrations by analyzing the dominant frequency of ground vibrations observed and also by reviewing various international standards.Frequency of the ground vibrations observed on the dam and tunnel from majority of the blasts was found to be more than 10 Hz and 50 Hz respectively.During the entire period of blasting,the blast vibrations were recorded to be far lower than the safe vibration level set for these structures.Maximum Vibration level of about 0.8 mm/s and 35 mm/s were observed on dam and tunnel respectively which are far lower than the safe vibration level adopted for these structures.Hence,the entire excavation work was completed successfully and safely,without endangering the safety of dam or tunnel. 展开更多
关键词 Controlled blasting Civil structure Ground vibration Attenuation relation
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Machine learning-based grayscale analyses for lithofacies identification of the Shahejie formation,Bohai Bay Basin,China 被引量:1
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作者 Yu-Fan Wang Shang Xu +4 位作者 Fang Hao Hui-Min Liu Qin-Hong Hu Ke-Lai Xi Dong Yang 《Petroleum Science》 2025年第1期42-54,共13页
It is of great significance to accurately and rapidly identify shale lithofacies in relation to the evaluation and prediction of sweet spots for shale oil and gas reservoirs.To address the problem of low resolution in... It is of great significance to accurately and rapidly identify shale lithofacies in relation to the evaluation and prediction of sweet spots for shale oil and gas reservoirs.To address the problem of low resolution in logging curves,this study establishes a grayscale-phase model based on high-resolution grayscale curves using clustering analysis algorithms for shale lithofacies identification,working with the Shahejie For-mation,Bohai Bay Basin,China.The grayscale phase is defined as the sum of absolute grayscale and relative amplitude as well as their features.The absolute grayscale is the absolute magnitude of the gray values and is utilized for evaluating the material composition(mineral composition+total organic carbon)of shale,while the relative amplitude is the difference between adjacent gray values and is used to identify the shale structure type.The research results show that the grayscale phase model can identify shale lithofacies well,and the accuracy and applicability of this model were verified by the fitting relationship between absolute grayscale and shale mineral composition,as well as corresponding re-lationships between relative amplitudes and laminae development in shales.Four lithofacies are iden-tified in the target layer of the study area:massive mixed shale,laminated mixed shale,massive calcareous shale and laminated calcareous shale.This method can not only effectively characterize the material composition of shale,but also numerically characterize the development degree of shale laminae,and solve the problem that difficult to identify millimeter-scale laminae based on logging curves,which can provide technical support for shale lithofacies identification,sweet spot evaluation and prediction of complex continental lacustrine basins. 展开更多
关键词 SHALE Machine learning Absolute grayscale Relative amplitude Grayscale phase model Lithofacies identification
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Chinese satellite frequency and orbit entity relation extraction method based on dynamic integrated learning 被引量:1
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作者 Yuanzhi He Zhiqiang Li Zheng Dou 《Digital Communications and Networks》 2025年第3期787-794,共8页
Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatical... Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatically mine available SFO resources.An essential aspect of constructing SFO-KG is the extraction of Chinese entity relations.Unfortunately,there is currently no publicly available Chinese SFO entity Relation Extraction(RE)dataset.Moreover,publicly available SFO text data contain numerous NA(representing for“No Answer”)relation category sentences that resemble other relation sentences and pose challenges in accurate classification,resulting in low recall and precision for the NA relation category in entity RE.Consequently,this issue adversely affects both the accuracy of constructing the knowledge graph and the efficiency of RE processes.To address these challenges,this paper proposes a method for extracting Chinese SFO text entity relations based on dynamic integrated learning.This method includes the construction of a manually annotated Chinese SFO entity RE dataset and a classifier combining features of SFO resource data.The proposed approach combines integrated learning and pre-training models,specifically utilizing Bidirectional Encoder Representation from Transformers(BERT).In addition,it incorporates one-class classification,attention mechanisms,and dynamic feedback mechanisms to improve the performance of the RE model.Experimental results show that the proposed method outperforms the traditional methods in terms of F1 value when extracting entity relations from both balanced and long-tailed datasets. 展开更多
关键词 Knowledge graph Relation extraction One-class classification Satellite frequency and orbit resources BERT
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A model for predicting marine shale gas sweet spots based on relative sea-level changes and its application 被引量:1
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作者 Hongyan Wang Zhensheng Shi +2 位作者 Xi Yang Qun Zhao Changmin Guo 《Energy Geoscience》 2025年第2期142-154,共13页
Gas-bearing shales have become a major source of future natural gas production worldwide.It has become increasingly urgent to develop a reliable prediction model and corresponding workflow for identifying shale gas sw... Gas-bearing shales have become a major source of future natural gas production worldwide.It has become increasingly urgent to develop a reliable prediction model and corresponding workflow for identifying shale gas sweet spots.The formation of gas-bearing shales is closely linked to relative sealevel changes,providing an important approach to predicting sweet spots in the Wufeng-Longmaxi shale in the southern Sichuan Basin,China.Three types of marine shale gas sweet spots are identified in the shale based on their formation stages combined with relative sea-level changes:early,middle,and late transgression types.This study develops a prediction model and workflow for identifying shale gas sweet spots by analyzing relative sea-level changes and facies sequences.Predicting shale gas sweet spots in an explored block using this model and workflow can provide a valuable guide for well design and hydraulic fracturing,significantly enhancing the efficiency of shale gas exploration and development.Notably,the new prediction model and workflow can be utilized for the rapid evaluation of the potential for shale gas development in new shale gas blocks or those with low exploratory maturity. 展开更多
关键词 Shale gas Sweet spot Relative sea-level change Wufeng-longmaxi shale Southern sichuan basin
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Pore-scale gas–water two-phase flow and relative permeability characteristics of disassociated hydrate reservoir 被引量:1
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作者 Yu-Xuan Xia Derek Elsworth +3 位作者 Sai Xu Xuan-Zhe Xia Jian-Chao Cai Cheng Lu 《Petroleum Science》 2025年第8期3344-3356,共13页
Clayey-silt natural gas hydrate reservoirs in the South China Sea exhibit loose and unconsolidated structures, heterogeneous pore structures, high clay mineral contents, and strong hydrophilicity. These characteristic... Clayey-silt natural gas hydrate reservoirs in the South China Sea exhibit loose and unconsolidated structures, heterogeneous pore structures, high clay mineral contents, and strong hydrophilicity. These characteristics complicate the gas-water two-phase flow process in porous media following hydrate decomposition, posing challenges for efficient development. This study examines the transport response of clayey-silt reservoir samples from the Shenhu area using gas-water two-phase flow experiments and CT scanning to explore changes in pore structure, gas-water distribution, and relative permeability under varying flow conditions. The results indicate that pore heterogeneity significantly influences flow characteristics. Gas preferentially displaces water in larger pores, forming fracture-like pores, which serve as preferential flow channels for gas migration. The preferential flow channels enhance gas-phase permeability up to 19 times that of the water phase when fluid pressures exceed total stresses. However,small pores retain liquid, leading to a high residual water saturation of 0.561. CT imaging reveals that these hydro-fractures improve gas permeability but also confine gas flow to specific channels. Pore network analysis shows that gas injection expands the pore-throat network, enhancing connectivity and forming fracture-like pores. Residual water remains trapped in smaller pores and throats, while structural changes, including new fractures, improve gas flow pathways and overall connectivity. Relative permeability curves demonstrate a narrow gas-water cocurrent-flow zone, a right-shifted iso-permeability point and high reservoir capillary pressure, indicating a strong "water-blocking" effect. The findings suggest that optimizing reservoir stimulation techniques to enhance fracture formation, reduce residual water saturation, and improve gas flow capacity is critical for efficient hydrate reservoir development. 展开更多
关键词 Clayey-silt reservoir Gasewater two-phase flow CT scanning Relative permeability Pore network model
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Effects of discrete fracture networks on simulating hydraulic fracturing,induced seismicity and trending transition of relative modulus in coal seams 被引量:1
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作者 Xin Zhang Guangyao Si +3 位作者 Qingsheng Bai Joung Oh Biao Jiao Wu Cai 《International Journal of Coal Science & Technology》 2025年第1期263-278,共16页
Discrete fracture network(DFN)commonly existing in natural rock masses plays an important role in geological complexity which can influence rock fracturing behaviour during fluid injection.This paper simulated the hyd... Discrete fracture network(DFN)commonly existing in natural rock masses plays an important role in geological complexity which can influence rock fracturing behaviour during fluid injection.This paper simulated the hydraulic fracturing process in lab-scale coal samples with DFNs and the induced seismic activities by the discrete element method(DEM).The effects of DFNs on hydraulic fracturing,induced seismicity and elastic property changes have been concluded.Denser DFNs can comprehensively decrease the peak injection pressure and injection duration.The proportion of strong seismic events increases first and then decreases with increasing DFN density.In addition,the relative modulus of the rock mass is derived innovatively from breakdown pressure,breakdown fracture length and the related initiation time.Increasing DFN densities among large(35–60 degrees)and small(0–30 degrees)fracture dip angles show opposite evolution trends in relative modulus.The transitional point(dip angle)for the opposite trends is also proportionally affected by the friction angle of the rock mass.The modelling results have much practical meaning to infer the density and geometry of pre-existing fractures and the elastic property of rock mass in the field,simply based on the hydraulic fracturing and induced seismicity monitoring data. 展开更多
关键词 Discrete fracture network Hydraulic fracturing Discrete element method Induced seismicity Relative modulus
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PROOFS OF CONJECTURES ON RAMANUJAN-TYPE SERIES OF LEVEL 3 被引量:1
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作者 John M.CAMPBELL 《Acta Mathematica Scientia》 2025年第4期1482-1496,共15页
The level 3 case for Ramanujan-type series has been considered as the most mysterious and the most challenging,out of all possible levels for Ramanujan-type series.This motivates the development of new techniques for ... The level 3 case for Ramanujan-type series has been considered as the most mysterious and the most challenging,out of all possible levels for Ramanujan-type series.This motivates the development of new techniques for constructing Ramanujan-type series of level 3.Chan and Liaw introduced an alternating analogue of the Borwein brothers’identity for Ramanujan-type series of level 3;subsequently,Chan,Liaw,and Tian formulated another proof of the Chan–Liaw identity,via the use of Ramanujan’s class invariant.Using the elliptic lambda function and the elliptic alpha function,we prove,via a limiting case of the Kummer–Goursat transformation,a new identity for evaluating the summands for alternating Ramanujan-type series of level 3,and we apply this new identity to prove three conjectured formulas for quadratic-irrational,Ramanujan-type series that had been discovered via numerical experiments with Maple in 2012 by Aldawoud.We also apply our identity to prove a new Ramanujan-type series of level 3 with a quartic convergence rate and quartic coefficients. 展开更多
关键词 Ramanujan-type series complete elliptic integral modular relation
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New Features and New Challenges of U.S.-Europe Relations Under Trump 2.0 被引量:1
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作者 Zhao Huaipu 《Contemporary World》 2025年第3期47-52,共6页
During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 202... During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 2024 presidential election of the United States has plunged the U.S.-Europe relations into more gloomy waters,ushering in a more complex and turbulent period of adjustment. 展开更多
关键词 new features turbulent period Trump U S Europe relations presidential election new challenges UNCERTAINTIES transatlantic alliance
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Relative vacuum reduction innovative processes applied in primary magnesium production-Comprehensive analysis of thermodynamics,resource,energy flow,and carbon emission 被引量:1
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作者 Xiaolong Li Tingan Zhang +3 位作者 Yan Liu Junhua Guo Jingzhong Xu Yuanyuan Liang 《Journal of Magnesium and Alloys》 2025年第7期3134-3149,共16页
Magnesium and magnesium alloys,serving as crucial lightweight structural materials and hydrogen storage elements,find extensive applications in space technology,aviation,automotive,and magnesium-based hydrogen industr... Magnesium and magnesium alloys,serving as crucial lightweight structural materials and hydrogen storage elements,find extensive applications in space technology,aviation,automotive,and magnesium-based hydrogen industries.The global production of primary magnesium has reached approximately 1.2 million tons per year,with anticipated diversification in future applications and significant market demand.Nevertheless,approximately 80%of the world’s primary magnesium is still manufactured through the Pidgeon process,grappling with formidable issues including high energy consumption,massive carbon emission,significant resource depletion,and environmental pollution.The implementation of the relative vacuum method shows potential in breaking through technological challenges in the Pidgeon process,facilitating clean,low-carbon continuous magnesium smelting.This paper begins by introducing the principles of the relative vacuum method.Subsequently,it elucidates various innovative process routes,including relative vacuum ferrosilicon reduction,aluminum thermal reduction co-production of spinel,and aluminum thermal reduction co-production of calcium aluminate.Finally,and thermodynamic foundations of the relative vacuum,a quantitative analysis of the material,energy flows,carbon emission,and production cost for several new processes is conducted,comparing and analyzing them against the Pidgeon process.The study findings reveal that,with identical raw materials,the relative vacuum silicon thermal reduction process significantly decreases raw material consumption,energy consumption,and carbon dioxide emissions by 15.86%,30.89%,and 26.27%,respectively,compared to the Pidgeon process.The relative vacuum process,using magnesite as the raw material and aluminum as the reducing agent,has the lowest magnesium-to-feed ratio,at only 3.385.Additionally,its energy consumption and carbon dioxide emissions are the lowest,at 1.817 tce/t Mg and 7.782 t CO_(2)/t Mg,respectively.The energy consumption and carbon emissions of the relative vacuum magnesium smelting process co-producing calcium aluminate(12CaO·7Al_(2)O_(3),3CaO·Al_(2)O_(3),and CaO·Al_(2)O_(3))are highly correlated with the consumption of dolomite in the raw materials.When the reduction temperature is around 1473.15 K,the critical volume fraction of magnesium vapor for different processes varies within the range of 5%–40%.Production cost analysis shows that the relative vacuum primary magnesium smelting process has significant economic benefits.This paper offers essential data support and theoretical guidance for achieving energy efficiency,carbon reduction in magnesium smelting,and the industrial adoption of innovative processes. 展开更多
关键词 Magnesium smelting Relative vacuum reduction process THERMODYNAMICS Resource and energy flow Carbon emission
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Multi-View Picture Fuzzy Clustering:A Novel Method for Partitioning Multi-View Relational Data 被引量:1
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作者 Pham Huy Thong Hoang Thi Canh +2 位作者 Luong Thi Hong Lan Nguyen Tuan Huy Nguyen Long Giang 《Computers, Materials & Continua》 2025年第6期5461-5485,共25页
Multi-view clustering is a critical research area in computer science aimed at effectively extracting meaningful patterns from complex,high-dimensional data that single-view methods cannot capture.Traditional fuzzy cl... Multi-view clustering is a critical research area in computer science aimed at effectively extracting meaningful patterns from complex,high-dimensional data that single-view methods cannot capture.Traditional fuzzy clustering techniques,such as Fuzzy C-Means(FCM),face significant challenges in handling uncertainty and the dependencies between different views.To overcome these limitations,we introduce a new multi-view fuzzy clustering approach that integrates picture fuzzy sets with a dual-anchor graph method for multi-view data,aiming to enhance clustering accuracy and robustness,termed Multi-view Picture Fuzzy Clustering(MPFC).In particular,the picture fuzzy set theory extends the capability to represent uncertainty by modeling three membership levels:membership degrees,neutral degrees,and refusal degrees.This allows for a more flexible representation of uncertain and conflicting data than traditional fuzzy models.Meanwhile,dual-anchor graphs exploit the similarity relationships between data points and integrate information across views.This combination improves stability,scalability,and robustness when handling noisy and heterogeneous data.Experimental results on several benchmark datasets demonstrate significant improvements in clustering accuracy and efficiency,outperforming traditional methods.Specifically,the MPFC algorithm demonstrates outstanding clustering performance on a variety of datasets,attaining a Purity(PUR)score of 0.6440 and an Accuracy(ACC)score of 0.6213 for the 3 Sources dataset,underscoring its robustness and efficiency.The proposed approach significantly contributes to fields such as pattern recognition,multi-view relational data analysis,and large-scale clustering problems.Future work will focus on extending the method for semi-supervised multi-view clustering,aiming to enhance adaptability,scalability,and performance in real-world applications. 展开更多
关键词 Multi-view clustering picture fuzzy sets dual anchor graph fuzzy clustering multi-view relational data
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