As blockchain technology rapidly evolves,smart contracts have seen widespread adoption in financial transactions and beyond.However,the growing prevalence of malicious Ponzi scheme contracts presents serious security ...As blockchain technology rapidly evolves,smart contracts have seen widespread adoption in financial transactions and beyond.However,the growing prevalence of malicious Ponzi scheme contracts presents serious security threats to blockchain ecosystems.Although numerous detection techniques have been proposed,existing methods suffer from significant limitations,such as class imbalance and insufficient modeling of transaction-related semantic features.To address these challenges,this paper proposes an oversampling-based detection framework for Ponzi smart contracts.We enhance the Adaptive Synthetic Sampling(ADASYN)algorithm by incorporating sample proximity to decision boundaries and ensuring realistic sample distributions.This enhancement facilitates the generation of high-quality minority class samples and effectively mitigates class imbalance.In addition,we design a Contract Transaction Graph(CTG)construction algorithm to preserve key transactional semantics through feature extraction from contract code.A graph neural network(GNN)is then applied for classification.This study employs a publicly available dataset from the XBlock platform,consisting of 318 verified Ponzi contracts and 6498 benign contracts.Sourced from real Ethereum deployments,the dataset reflects diverse application scenarios and captures the varied characteristics of Ponzi schemes.Experimental results demonstrate that our approach achieves an accuracy of 96%,a recall of 92%,and an F1-score of 94%in detecting Ponzi contracts,outperforming state-of-the-art methods.展开更多
背景:激素诱导股骨头坏死的发病机制复杂,涉及血管内皮损伤、骨细胞凋亡、炎症反应和骨代谢紊乱。微小RNA(microRNAs,miRNA)作为基因表达的关键调控因子在激素诱导股骨头坏死中扮演着重要角色。目的:综合分析miRNA在激素诱导股骨头坏死...背景:激素诱导股骨头坏死的发病机制复杂,涉及血管内皮损伤、骨细胞凋亡、炎症反应和骨代谢紊乱。微小RNA(microRNAs,miRNA)作为基因表达的关键调控因子在激素诱导股骨头坏死中扮演着重要角色。目的:综合分析miRNA在激素诱导股骨头坏死病理过程中的作用,评估miRNA作为激素诱导股骨头坏死生物标志物的潜力与治疗策略的最新进展。方法:通过计算机检索PubMed、Web of Science、CNKI和万方数据库中的相关文献,使用特定的关键词进行筛选,并根据纳入和排除标准选择相关文章。通过阅读标题和摘要或全文,排除与主题相关性差或内容重复的文献,最终筛选出76篇文献进行分析。结果与结论:miRNA通过与目标mRNA的3’非翻译区结合调控基因表达,影响细胞增殖、分化、凋亡和应激反应。特定的miRNA如miR-33-5p、miR-99a、miR-106b-5p、miR-155、miR-146a和miR-21在激素诱导股骨头坏死的血管损伤、炎症反应、骨细胞分化和凋亡中起着核心调控作用;此外,miRNA的表达模式与激素诱导股骨头坏死的发病机制密切相关,显示出作为生物标志物的潜力。尽管miRNA作为生物标志物展现出巨大潜力,但样本量有限和缺乏多人群验证限制了其普适性;此外,miRNA治疗策略的有效性和安全性(包括脱靶效应和递送问题)仍是实现临床应用的主要挑战。展开更多
背景:肢体间不对称是人类生长发育过程中的一般现象,长期专项训练可使运动员肢体间不对称发生特异性适应。目的:回顾了体育运动中肢体间不对称的形成原因、表现形式及对运动能力的影响,并概述了相关评估方法及干预策略。方法:检索中国...背景:肢体间不对称是人类生长发育过程中的一般现象,长期专项训练可使运动员肢体间不对称发生特异性适应。目的:回顾了体育运动中肢体间不对称的形成原因、表现形式及对运动能力的影响,并概述了相关评估方法及干预策略。方法:检索中国知网、万方、PubMed及Web of Science数据库建库至2024年9月间收录的文献,中文检索词为“不对称,对称,失衡,平衡,力量,爆发力,跳跃,跑,人体测量学,运动损伤,运动能力,运动表现”,英文检索词为“asymmetry,asymmetries,asymmetric,asymmetrical,imbalance,strength,power,force,jump,sprint,athletic performance,anthropometry,injury”。排除重复发表、内容不相关及会议文献后,最终纳入131篇文献进行分析。结果与结论:(1)肢体间不对称可受遗传、任务、训练、损伤、疲劳和肢体偏好等因素影响,主要表现为解剖结构、力量表现、专项任务不对称等形式;(2)肢体间不对称增大可导致双侧同相位对称类运动能力受损,但与双侧异相位对称类运动能力间关系尚不明确;(3)训练干预可有效改善肢体间不对称,且单侧训练效果优于双侧,训练方式和内容选择应符合专项需求;(4)为进一步厘清肢体间不对称与运动能力间的关系,建议未来研究秉承肢体间不对称的“任务特异性”理念,规范研究设计,选择敏感测试手段与指标,统一计算方式以提供更多的高质量证据,并分类制定不同专项肢体间不对称的预警阈值标准。展开更多
背景:非创伤性股骨头坏死的发病机制尚不明确,其中血脂代谢紊乱是引起非创伤性股骨头坏死的重要假说,通过调节血脂代谢来抑制股骨头坏死的进展,已成为当前治疗非创伤性股骨头坏死的重要方法。目的:综述非创伤性股骨头坏死与脂质代谢紊...背景:非创伤性股骨头坏死的发病机制尚不明确,其中血脂代谢紊乱是引起非创伤性股骨头坏死的重要假说,通过调节血脂代谢来抑制股骨头坏死的进展,已成为当前治疗非创伤性股骨头坏死的重要方法。目的:综述非创伤性股骨头坏死与脂质代谢紊乱的关系及治疗研究进展。方法:以“股骨头坏死,非创伤性股骨头坏死,骨坏死,骨与脂质代谢,股骨头坏死与脂质,股骨头坏死机制,股骨头坏死通路,股骨头坏死治疗”为中文检索词,以“osteonecrosis of femoral head,Nontraumatic osteonecrosis of femoral head,femoral head necrosis,osteonecrosis and lipid,lipid metabolism osteonecrosis,polymorphisms osteonecrosis of femoral head,pathway osteonecrosis of femoral head,steroid-induced osteonecrosis of the femoral head,alcohol-induced osteonecrosis of femoral head”为英文检索词,检索中国知网、万方医学网、中华医学期刊数据库、PubMed数据库,最终纳入104篇文献进行归纳总结。结果与结论:①股骨头坏死患者常伴随血脂异常,研究发现总胆固醇、三酰甘油、低密度脂蛋白胆固醇、载脂蛋白B水平升高与载脂蛋白A1水平降低是引起股骨头坏死的危险因素,并且不同诱因的股骨头坏死患者血脂水平存在差异;②激素和酒精作为非创伤性股骨头坏死的两大诱因,可以诱导骨髓间充质干细胞的成脂分化,使骨髓腔内脂肪细胞增多、脂滴聚集,最终导致股骨头坏死;③许多与脂质代谢相关的分子和脂肪因子,如脂联素、瘦素、脂质运载蛋白2等都被证实与股骨头坏死有关;④过氧化物酶体增殖物激活受体γ、Wnt/β-catenin、腺苷酸环化蛋白激酶等信号通路可以改变骨髓间充质干细胞的成骨-成脂分化潜能,从而参与股骨头坏死的发生发展;磷脂酰肌醇3激酶/蛋白激酶B、骨形态发生蛋白2等脂代谢信号通路也与股骨头坏死有关,可能通过调节脂质代谢影响股骨头坏死的进展;⑤研究发现,虫草素、三七总皂苷、骨蚀灵胶囊等中药和他汀类药物可以通过改善脂质代谢紊乱达到治疗非创伤性股骨头坏死的效果。展开更多
背景:高频重复经颅磁刺激因非侵入性调控大脑功能的潜在益处而备受关注,但目前尚无研究从宏观角度分析该研究领域的最新研究现状和发展趋势。目的:通过可视化分析来确定高频重复经颅磁刺激领域的研究热点、现状和前沿。方法:检索Web of ...背景:高频重复经颅磁刺激因非侵入性调控大脑功能的潜在益处而备受关注,但目前尚无研究从宏观角度分析该研究领域的最新研究现状和发展趋势。目的:通过可视化分析来确定高频重复经颅磁刺激领域的研究热点、现状和前沿。方法:检索Web of Science核心数据库中高频重复经颅磁刺激领域的相关研究,文献检索时限为2014-01-01/2024-11-15,采用CiteSpace进行发文量分析,国家/地区、机构和作者合作分析,被引期刊、文献共被引和学科领域分析,以及关键词共现、聚类和突现分析等,绘制可视化分析知识图谱。结果与结论:共纳入860篇文献,高频重复经颅磁刺激领域的发文量在2014-2022年总体呈上升趋势,在2022-2024年呈下降趋势,中国是发文量最多的国家,发文量最高的机构是根特大学,发文量高的机构多为高校;发文量最高的作者是根特大学的Chris Baeken,发文量靠前的作者之间以及世界各地的机构之间合作较少。高频重复经颅磁刺激领域热点关键词以抑郁症、脑卒中、神经源性疼痛和帕金森病等为主,突现关键词以轻度认知障碍为主,研究方向较多元化。高频重复经颅磁刺激的研究热度总体呈上升趋势,研究内容主要围绕高频重复经颅磁刺激在精神疾病和神经系统疾病的临床应用,以及对这些领域作用机制的探索。未来该领域的研究方向可能聚焦于高频重复经颅磁刺激在临床应用时使用多种治疗参数来作用不同的靶点,以及其在不同领域中的应用和作用机制。展开更多
Firedamp and coal dust explosion constitute a lion’s share in mine accidents in a global mining scenario.This paper reports a list of mine explosion disasters since last two decades,a critical review of the different...Firedamp and coal dust explosion constitute a lion’s share in mine accidents in a global mining scenario.This paper reports a list of mine explosion disasters since last two decades,a critical review of the different prevention and constructive measures,and its recent development to avoid firedamp and coal dust explosion.Preventive legislation in core coal-producing countries,viz.China,USA,Australia,South Africa,and India related to firedamp and coal dust explosion are critically analysed.Accidents occurred due to explosion after Nationalisation of Coal Mines(1973)in India are listed.Prevention and constructive measures adopted in India are critically analysed with respect to the global mining scenario.Measures like methane credit concept,classification of mines/seams with respect to explosion risk zone,deflagration index;installation of automatic fire warning devices,canopy air curtain technology,explosion-prevention measures,such as fire-retardant materials,inhibitors,extinguishing agent,dust suppressor,and active explosion barrier are discussed in detail to avoid explosion and thereby adhering to zero accident policy due to coal mine explosion.展开更多
基金supported by the Key Project of Joint Fund of the National Natural Science Foundation of China“Research on Key Technologies and Demonstration Applications for Trusted and Secure Data Circulation and Trading”(U24A20241)the National Natural Science Foundation of China“Research on Trusted Theories and Key Technologies of Data Security Trading Based on Blockchain”(62202118)+4 种基金the Major Scientific and Technological Special Project of Guizhou Province([2024]014)Scientific and Technological Research Projects from the Guizhou Education Department(Qian jiao ji[2023]003)the Hundred-Level Innovative Talent Project of the Guizhou Provincial Science and Technology Department(Qiankehe Platform Talent-GCC[2023]018)the Major Project of Guizhou Province“Research and Application of Key Technologies for Trusted Large Models Oriented to Public Big Data”(Qiankehe Major Project[2024]003)the Guizhou Province Computational Power Network Security Protection Science and Technology Innovation Talent Team(Qiankehe Talent CXTD[2025]029).
文摘As blockchain technology rapidly evolves,smart contracts have seen widespread adoption in financial transactions and beyond.However,the growing prevalence of malicious Ponzi scheme contracts presents serious security threats to blockchain ecosystems.Although numerous detection techniques have been proposed,existing methods suffer from significant limitations,such as class imbalance and insufficient modeling of transaction-related semantic features.To address these challenges,this paper proposes an oversampling-based detection framework for Ponzi smart contracts.We enhance the Adaptive Synthetic Sampling(ADASYN)algorithm by incorporating sample proximity to decision boundaries and ensuring realistic sample distributions.This enhancement facilitates the generation of high-quality minority class samples and effectively mitigates class imbalance.In addition,we design a Contract Transaction Graph(CTG)construction algorithm to preserve key transactional semantics through feature extraction from contract code.A graph neural network(GNN)is then applied for classification.This study employs a publicly available dataset from the XBlock platform,consisting of 318 verified Ponzi contracts and 6498 benign contracts.Sourced from real Ethereum deployments,the dataset reflects diverse application scenarios and captures the varied characteristics of Ponzi schemes.Experimental results demonstrate that our approach achieves an accuracy of 96%,a recall of 92%,and an F1-score of 94%in detecting Ponzi contracts,outperforming state-of-the-art methods.
文摘背景:激素诱导股骨头坏死的发病机制复杂,涉及血管内皮损伤、骨细胞凋亡、炎症反应和骨代谢紊乱。微小RNA(microRNAs,miRNA)作为基因表达的关键调控因子在激素诱导股骨头坏死中扮演着重要角色。目的:综合分析miRNA在激素诱导股骨头坏死病理过程中的作用,评估miRNA作为激素诱导股骨头坏死生物标志物的潜力与治疗策略的最新进展。方法:通过计算机检索PubMed、Web of Science、CNKI和万方数据库中的相关文献,使用特定的关键词进行筛选,并根据纳入和排除标准选择相关文章。通过阅读标题和摘要或全文,排除与主题相关性差或内容重复的文献,最终筛选出76篇文献进行分析。结果与结论:miRNA通过与目标mRNA的3’非翻译区结合调控基因表达,影响细胞增殖、分化、凋亡和应激反应。特定的miRNA如miR-33-5p、miR-99a、miR-106b-5p、miR-155、miR-146a和miR-21在激素诱导股骨头坏死的血管损伤、炎症反应、骨细胞分化和凋亡中起着核心调控作用;此外,miRNA的表达模式与激素诱导股骨头坏死的发病机制密切相关,显示出作为生物标志物的潜力。尽管miRNA作为生物标志物展现出巨大潜力,但样本量有限和缺乏多人群验证限制了其普适性;此外,miRNA治疗策略的有效性和安全性(包括脱靶效应和递送问题)仍是实现临床应用的主要挑战。
文摘背景:肢体间不对称是人类生长发育过程中的一般现象,长期专项训练可使运动员肢体间不对称发生特异性适应。目的:回顾了体育运动中肢体间不对称的形成原因、表现形式及对运动能力的影响,并概述了相关评估方法及干预策略。方法:检索中国知网、万方、PubMed及Web of Science数据库建库至2024年9月间收录的文献,中文检索词为“不对称,对称,失衡,平衡,力量,爆发力,跳跃,跑,人体测量学,运动损伤,运动能力,运动表现”,英文检索词为“asymmetry,asymmetries,asymmetric,asymmetrical,imbalance,strength,power,force,jump,sprint,athletic performance,anthropometry,injury”。排除重复发表、内容不相关及会议文献后,最终纳入131篇文献进行分析。结果与结论:(1)肢体间不对称可受遗传、任务、训练、损伤、疲劳和肢体偏好等因素影响,主要表现为解剖结构、力量表现、专项任务不对称等形式;(2)肢体间不对称增大可导致双侧同相位对称类运动能力受损,但与双侧异相位对称类运动能力间关系尚不明确;(3)训练干预可有效改善肢体间不对称,且单侧训练效果优于双侧,训练方式和内容选择应符合专项需求;(4)为进一步厘清肢体间不对称与运动能力间的关系,建议未来研究秉承肢体间不对称的“任务特异性”理念,规范研究设计,选择敏感测试手段与指标,统一计算方式以提供更多的高质量证据,并分类制定不同专项肢体间不对称的预警阈值标准。
文摘背景:非创伤性股骨头坏死的发病机制尚不明确,其中血脂代谢紊乱是引起非创伤性股骨头坏死的重要假说,通过调节血脂代谢来抑制股骨头坏死的进展,已成为当前治疗非创伤性股骨头坏死的重要方法。目的:综述非创伤性股骨头坏死与脂质代谢紊乱的关系及治疗研究进展。方法:以“股骨头坏死,非创伤性股骨头坏死,骨坏死,骨与脂质代谢,股骨头坏死与脂质,股骨头坏死机制,股骨头坏死通路,股骨头坏死治疗”为中文检索词,以“osteonecrosis of femoral head,Nontraumatic osteonecrosis of femoral head,femoral head necrosis,osteonecrosis and lipid,lipid metabolism osteonecrosis,polymorphisms osteonecrosis of femoral head,pathway osteonecrosis of femoral head,steroid-induced osteonecrosis of the femoral head,alcohol-induced osteonecrosis of femoral head”为英文检索词,检索中国知网、万方医学网、中华医学期刊数据库、PubMed数据库,最终纳入104篇文献进行归纳总结。结果与结论:①股骨头坏死患者常伴随血脂异常,研究发现总胆固醇、三酰甘油、低密度脂蛋白胆固醇、载脂蛋白B水平升高与载脂蛋白A1水平降低是引起股骨头坏死的危险因素,并且不同诱因的股骨头坏死患者血脂水平存在差异;②激素和酒精作为非创伤性股骨头坏死的两大诱因,可以诱导骨髓间充质干细胞的成脂分化,使骨髓腔内脂肪细胞增多、脂滴聚集,最终导致股骨头坏死;③许多与脂质代谢相关的分子和脂肪因子,如脂联素、瘦素、脂质运载蛋白2等都被证实与股骨头坏死有关;④过氧化物酶体增殖物激活受体γ、Wnt/β-catenin、腺苷酸环化蛋白激酶等信号通路可以改变骨髓间充质干细胞的成骨-成脂分化潜能,从而参与股骨头坏死的发生发展;磷脂酰肌醇3激酶/蛋白激酶B、骨形态发生蛋白2等脂代谢信号通路也与股骨头坏死有关,可能通过调节脂质代谢影响股骨头坏死的进展;⑤研究发现,虫草素、三七总皂苷、骨蚀灵胶囊等中药和他汀类药物可以通过改善脂质代谢紊乱达到治疗非创伤性股骨头坏死的效果。
文摘背景:高频重复经颅磁刺激因非侵入性调控大脑功能的潜在益处而备受关注,但目前尚无研究从宏观角度分析该研究领域的最新研究现状和发展趋势。目的:通过可视化分析来确定高频重复经颅磁刺激领域的研究热点、现状和前沿。方法:检索Web of Science核心数据库中高频重复经颅磁刺激领域的相关研究,文献检索时限为2014-01-01/2024-11-15,采用CiteSpace进行发文量分析,国家/地区、机构和作者合作分析,被引期刊、文献共被引和学科领域分析,以及关键词共现、聚类和突现分析等,绘制可视化分析知识图谱。结果与结论:共纳入860篇文献,高频重复经颅磁刺激领域的发文量在2014-2022年总体呈上升趋势,在2022-2024年呈下降趋势,中国是发文量最多的国家,发文量最高的机构是根特大学,发文量高的机构多为高校;发文量最高的作者是根特大学的Chris Baeken,发文量靠前的作者之间以及世界各地的机构之间合作较少。高频重复经颅磁刺激领域热点关键词以抑郁症、脑卒中、神经源性疼痛和帕金森病等为主,突现关键词以轻度认知障碍为主,研究方向较多元化。高频重复经颅磁刺激的研究热度总体呈上升趋势,研究内容主要围绕高频重复经颅磁刺激在精神疾病和神经系统疾病的临床应用,以及对这些领域作用机制的探索。未来该领域的研究方向可能聚焦于高频重复经颅磁刺激在临床应用时使用多种治疗参数来作用不同的靶点,以及其在不同领域中的应用和作用机制。
基金The authors are grateful to the Ministry of Coal,Government of India(No.CIL/R&D/01/60/2016)for financial support。
文摘Firedamp and coal dust explosion constitute a lion’s share in mine accidents in a global mining scenario.This paper reports a list of mine explosion disasters since last two decades,a critical review of the different prevention and constructive measures,and its recent development to avoid firedamp and coal dust explosion.Preventive legislation in core coal-producing countries,viz.China,USA,Australia,South Africa,and India related to firedamp and coal dust explosion are critically analysed.Accidents occurred due to explosion after Nationalisation of Coal Mines(1973)in India are listed.Prevention and constructive measures adopted in India are critically analysed with respect to the global mining scenario.Measures like methane credit concept,classification of mines/seams with respect to explosion risk zone,deflagration index;installation of automatic fire warning devices,canopy air curtain technology,explosion-prevention measures,such as fire-retardant materials,inhibitors,extinguishing agent,dust suppressor,and active explosion barrier are discussed in detail to avoid explosion and thereby adhering to zero accident policy due to coal mine explosion.
