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2012-2023年山东省山东大学儿童布鲁氏菌病流行病学特征及感染途径分析
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作者 刘建宝 黄淑娟 +5 位作者 杨丽 常彩云 王京京 张元元 邢晨 隋庆梅 《疾病监测》 北大核心 2025年第4期450-453,共4页
目的分析山东省山东大学儿童布鲁氏菌病(布病)的流行病学特征及感染途径,为山东大学儿童布病防治提供依据。方法收集2012—2023年山东大学儿童布病疫情及个案调查资料,应用描述流行病学分析的方法对病例流行病学特征、症状及诊断情况、感染途... 目的分析山东省山东大学儿童布鲁氏菌病(布病)的流行病学特征及感染途径,为山东大学儿童布病防治提供依据。方法收集2012—2023年山东大学儿童布病疫情及个案调查资料,应用描述流行病学分析的方法对病例流行病学特征、症状及诊断情况、感染途径进行统计分析。结果2012—2023年山东大学共报告儿童布病44例,年平均发病率为0.05/10万,各年发病率差异有统计学意义(χ^(2)=30.439,P=0.001)。春夏季多发,男性患儿25例,女性患儿19例,男女性别比为1.32∶1,最小年龄1岁,最大年龄14岁,6~岁为发病高峰年龄,占47.73%(21/44)。各区(县)均有病例报告,商河县和历城区相对较多,分别占36.59%(15/44)、24.39%(10/44),患儿大部分来自农村,占86.36%(38/44)。感染途径以直接接触或呼吸道传播为主,占77.27%(34/44),饮食传播途径占20.45%(9/44)。临床症状以发热、肌肉关节酸痛、乏力、多汗为主,确诊时间中位数12(7,30)d。结论山东大学儿童布病分布于各区(县),农村地区多发,存在疫情重点地区,有高发季节和高发年龄,经直接接触和呼吸道传播是儿童布病主要传播途径,确诊时间长,下一步应加强对儿童布病疫情重点地区的防控工作,加强布病知识宣传和医务人员诊断培训工作。 展开更多
关键词 布鲁氏菌病 儿童 流行病学特征 感染途径
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基于大模型的不动产登记智能问答方法 被引量:1
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作者 董承玮 李云汉 +1 位作者 邢晨 刘世凡 《北京测绘》 2025年第3期253-258,共6页
为探索如何在不动产登记业务中提供智能问答服务,本文提出一种基于大语言模型的不动产政策智能问答方法,并结合不动产政策知识库与信息检索提升问答准确性。该方法首先通过搜索引擎和语义检索从政策知识库得到政策文本候选集合;然后利... 为探索如何在不动产登记业务中提供智能问答服务,本文提出一种基于大语言模型的不动产政策智能问答方法,并结合不动产政策知识库与信息检索提升问答准确性。该方法首先通过搜索引擎和语义检索从政策知识库得到政策文本候选集合;然后利用排序模型进行排序,得到与问题最相关的候选政策文本;最后基于问题、政策文本构建提示(Prompt)并输入大模型生成答案。相较于传统方法,该方法在确保答案专业性和准确性的同时,提供了更灵活、自然的自助问答服务,对构建不动产登记智慧问答系统具有一定的参考意义。 展开更多
关键词 不动产登记 智能问答 知识库 语义检索 大模型
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糖尿病与颈动脉内膜剥脱术后并发症发生率的相关性分析
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作者 张鹏 王志强 +5 位作者 王浩 张西科 商淑玲 冯青叶 兴辰 曹英肖 《临床神经外科杂志》 2025年第2期210-214,共5页
目的 探讨糖尿病与颈动脉内膜剥脱术(CEA)术后并发症发生率之间的相关性。方法 纳入2012年1月—2022年12月在邯郸市第一医院及邢台市人民医院接受CEA的370例患者,根据是否合并糖尿病分为糖尿病组与非糖尿病组。糖尿病组共139例(37.6%),... 目的 探讨糖尿病与颈动脉内膜剥脱术(CEA)术后并发症发生率之间的相关性。方法 纳入2012年1月—2022年12月在邯郸市第一医院及邢台市人民医院接受CEA的370例患者,根据是否合并糖尿病分为糖尿病组与非糖尿病组。糖尿病组共139例(37.6%),其中50例为主要应用胰岛素治疗糖尿病的患者(36.0%),89例为仅应用口服降糖药物治疗糖尿病的患者(64.0%);非糖尿病组共231例(62.4%)。结果 除糖尿病患者的血脂异常、冠心病、外周血管疾病患病率较高外,其余患者的术前特征相似。糖尿病患者术后脑血管病发生率(3.6%)显著高于非糖尿病患者(0.4%)(P=0.03);糖尿病患者术后心力衰竭发生率(5.8%)显著高于非糖尿病患者(1.3%)(P=0.023);糖尿病患者术后伤口感染发生率(3.6%)显著高于非糖尿病患者为(0%)(P=0.007)。致死性心脏事件、神经系统事件及死亡率两组间无统计学意义(P>0.05)。糖尿病组术后总并发症的比例是非糖尿病组的2倍以上(分别为20.1%和7.4%,P<0.001)。结论 糖尿病增加了CEA的手术风险,但致死性风险并无明显增加。仅接受口服降糖药物治疗的患者比胰岛素治疗的患者有更高的CEA术后并发症发生率。 展开更多
关键词 颈动脉内膜剥脱术 糖尿病 术后并发症
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大型医疗设备使用效益评价指标体系构建研究
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作者 斯少婷 付海鸿 +4 位作者 行辰 王绍博 胡文静 林洪义 罗林枝 《中国医疗设备》 2025年第10期102-107,共6页
目的构建大型医疗设备使用效益评价体系,从而提高医疗设备利用率,提升医疗设备精细化、数字化、智能化、科学化管理水平。方法通过文献分析和焦点小组访谈建立大型医疗设备使用效益评价指标池,采用德尔菲法与层次分析法确定评价指标体... 目的构建大型医疗设备使用效益评价体系,从而提高医疗设备利用率,提升医疗设备精细化、数字化、智能化、科学化管理水平。方法通过文献分析和焦点小组访谈建立大型医疗设备使用效益评价指标池,采用德尔菲法与层次分析法确定评价指标体系及各级指标权重。结果最终构建的评价体系涵盖社会效益、经济效益、管理效益、科教效益4个一级指标及17个二级指标,且二级指标按属性细分为效率指标与效果指标;一级指标权重依次为43.93%、31.07%、14.64%、10.36%,二级指标权重区间为0.82%~19.90%,其中设备使用率(19.90%)、投资收益率(14.08%)、设备诊疗人次(11.49%)权重较高。结论该指标体系兼顾多维度评价需求,可客观反映公立医院大型医疗设备使用效益,既能弥补传统评价“重采购轻管理”的不足,又能为设备采购决策、日常使用监管及运维优化提供科学数据支持;后续可进一步探索其在不同规模、地区医院的适用性,结合实际需求优化完善。 展开更多
关键词 大型医疗设备 评价指标 社会效益 经济效益 管理效益 科教效益
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STAT活化抑制蛋白2基因在前列腺癌中的表达水平及与临床病理特征的关系
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作者 李唯尊 邢晨 安恒庆 《实用医学杂志》 北大核心 2025年第18期2844-2852,共9页
目的 探讨STAT活化抑制蛋白2(protein inhibitor of the activated STAT2, PIAS2)基因在前列腺癌中的表达水平及其与临床病理特征的关系,以及PIAS2对前列腺癌脂质代谢重编程的潜在作用。方法 采用癌症基因图谱(The Cancer Genome Atlas ... 目的 探讨STAT活化抑制蛋白2(protein inhibitor of the activated STAT2, PIAS2)基因在前列腺癌中的表达水平及其与临床病理特征的关系,以及PIAS2对前列腺癌脂质代谢重编程的潜在作用。方法 采用癌症基因图谱(The Cancer Genome Atlas Program,TCGA)数据库和人类蛋白图谱(Human Protein Atas,HPA)免疫组化分析显示PIAS2蛋白的表达情况;采用qRT-PCR、Western bolt及免疫组化检测前列腺癌组织和周围癌旁组织中PIAS2的表达,并分析其与患者临床病理特征的关系;慢病毒感染前列腺癌细胞株PC-3M,稳定敲低PIAS2,通过超高效液相色谱质谱技术(UPLC-MS)进行脂质组学分析。结果 TCGA分析显示PIAS2在前列腺癌组织的表达高于癌旁组织,HPA免疫组化分析显示PIAS2蛋白在前列腺癌组织高表达;PIAS2 mRNA和蛋白在前列腺癌中的表达量相较于癌旁组织均有显著提升,差异有统计学意义(P<0.05);免疫组织化学显示PIAS2蛋白表达主要定位在前列腺的细胞核,且前列腺癌组织的AOD值显著高于癌旁组织:临床病理参数研究结果显示,PIAS2与Gleason评分、TNM分期具有相关性(P<0.05),而与患者年龄、PSA及淋巴结转移之间相关性无统计学意义(P > 0.05);UPLC-MS分析提示,敲降PIAS2影响10种脂类变化,与shNC组相比,shPIAS2组的磷脂酰胆碱和磷脂酰乙醇胺的含量下调,磷脂酰肌醇、磷脂酰丝氨酸、二酰基甘油和三酰基甘油的含量上调。结论 PIAS2蛋白的表达量在前列腺癌组织中明显升高,提示PIAS2与前列腺癌的发生发展有关,其发病机制可能与前列腺癌的脂质代谢异常相关。 展开更多
关键词 前列腺癌 STAT活化抑制蛋白2 免疫组织化学 脂质代谢重编程
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颈部超声血流参数与突发性耳聋听力损失程度及转归不良的关系分析 被引量:1
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作者 康欣 李海朋 +4 位作者 董亚男 闫丽纬 邢晨 常伟 云丽媛 《影像科学与光化学》 2025年第3期57-66,共10页
目的:探讨颈部超声血流参数与突发性耳聋(SSHL)患者听力损失程度及转归不良之间的关系。方法:回顾性研究纳入2021年1月至2024年1月期间诊断为SSHL的155例患者作为疾病组,检测颈部超声血流参数,包括双侧颈内动脉、椎动脉和锁骨下动脉的... 目的:探讨颈部超声血流参数与突发性耳聋(SSHL)患者听力损失程度及转归不良之间的关系。方法:回顾性研究纳入2021年1月至2024年1月期间诊断为SSHL的155例患者作为疾病组,检测颈部超声血流参数,包括双侧颈内动脉、椎动脉和锁骨下动脉的舒张末期容积(EDV)和收缩期峰值流速(PSV),与148名年龄和性别相匹配的健康对照组进行比较,同时比较不同听力损失程度患者颈部超声血流参数。根据疾病组病情转归分为转归良好组、转归不良组,比较两组临床资料,采用Logistic回归法分析转归不良的影响因素。采用Pearson相关分析评估疾病组颈部超声血流参数与听力损失程度、转归不良之间的关系。结果:疾病组排除4例中途转院、3例自行放弃治疗的患者后,共分析148例患者;与健康对照组相比,疾病组所有评估动脉的EDV和PSV均降低(P<0.05);疾病组不同听力损失程度患者所有评估动脉的EDV和PSV均存在差异(P<0.05),中度、重度及极重度患者低于轻度患者(P<0.05),重度、极重度患者低于中度患者(P<0.05),极重度患者低于重度患者(P<0.05);疾病组转归不良发生率为28.38%(42/148);Logistic回归分析确定听力曲线类型全聋型[比值比(OR)=1.914,95%置信区间(95%CI):1.283~2.854]是转归不良的危险因素(P<0.05),颈内动脉EDV(OR=0.529,95%CI:0.376~0.745)、椎动脉EDV(OR=0.552,95%CI:0.405~0.752)、锁骨下动脉EDV(OR=0.538,95%CI:0.356~0.814)、颈内动脉PSV(OR=0.555,95%CI:0.420~0.735)、椎动脉PSV(OR=0.569,95%CI:0.435~0.746)、锁骨下动脉PSV(OR=0.560,95%CI:0.389~0.807)及高压氧治疗(OR=0.524,95%CI:0.410~0.669)是转归不良的保护因素(P<0.05);Pearson相关分析确定疾病组所有评估动脉的EDV和PSV均与听力损失程度、转归不良呈负相关(P<0.05)。结论:SSHL患者颈部超声血流参数与听力损失程度和转归不良密切相关,且全聋型听力曲线类型是转归不良的危险因素,高压氧治疗是转归不良的保护因素,这些发现可能有助于SSHL的临床评估和治疗计划制定。 展开更多
关键词 突发性耳聋 颈部超声 血流参数 听力损失程度 转归
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Enhanced recovery after surgery-based evidence-based care plus ice stimulation for thirst management in convalescent patients following digestive surgery under general anesthesia
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作者 Li chen Bi-Xi Li +4 位作者 Qiu-Zhi Gan Rui-Ge Guo xing chen Xi Shen Yan chen 《World Journal of Gastrointestinal Surgery》 2025年第3期198-205,共8页
BACKGROUND Thirst management in convalescent patients recovering from a digestive surgery performed under general anesthesia requires attention.A simple,practical,and safe method can effectively relieve thirst symptom... BACKGROUND Thirst management in convalescent patients recovering from a digestive surgery performed under general anesthesia requires attention.A simple,practical,and safe method can effectively relieve thirst symptoms in such patients.AIM To evaluate the enhanced recovery after surgery(ERAS)-based evidence-based care(EBC)plus ice stimulation therapy for thirst management of convalescent patients following digestive surgery performed under general anesthesia.METHODS A total of 191 patients convalescing after digestive surgery performed under general anesthesia between March 2020 and February 2023 and experiencing thirst were selected.In total,89 patients and 102 patients in the control and research groups received routine care and ERAS-based EBC plus ice stimulation therapy,respectively.The following data were comparatively analyzed:(1)Thirst degree(thirst intensity numerical rating scale)and thirst distress(TD)degree(TD scale);(2)Oral mucosal wetness;(3)Unstimulated whole salivary flow rate(UWSFR);(4)Adverse reactions(palpitation,fatigue,chapped lips,and nausea and vomiting);and(5)Nursing satisfaction.RESULTS After nursing,thirst degree and distress were statistically lower in the research group than in the control group.Additionally,compared with the control group,the research group exhibited a lower degree of oral mucosal wetness,higher UWSFR,fewer adverse reactions,and more total nursing satisfaction.CONCLUSION ERAS-based EBC plus ice stimulation therapy can effectively alleviate thirst in convalescent patients recovering from a digestive surgery performed under general anesthesia.It can alleviate xerostomia symptoms,reduce adverse reactions,and improve patient comfort. 展开更多
关键词 Enhanced recovery after surgery Evidence-based care Ice stimulation therapy Convalescent patients Digestive surgery General anesthesia THIRST
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Synergistic Li_(6)PS_(5)Cl@Li_(3)OCl composite electrolyte for high-performance all-solid-state lithium batteries
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作者 Yuzhe Zhang Haolong Chang +8 位作者 Aiguo Han Shijie Xu Xinyu Wang Shunjin Yang Xiaohu Hu Yujiang Sun Xiao Sun xing chen Yongan Yang 《Green Energy & Environment》 2025年第4期793-803,共11页
Li_(6)PS_(5)Cl is a highly wanted sulfide-solid-electrolyte(SSE)for developing all-solid-state lithium batteries,due to its high ionic conductivity,good processability and abundant compositional elements.However,its c... Li_(6)PS_(5)Cl is a highly wanted sulfide-solid-electrolyte(SSE)for developing all-solid-state lithium batteries,due to its high ionic conductivity,good processability and abundant compositional elements.However,its cyclability is poor because of harmful side reactions at the Li_(6)PS_(5)Cl/Li interface and growth of lithium dendrites inside Li_(6)PS_(5)Cl phase.Herein,we report a simple interface-engineering remedy to boost the electrochemical performance of Li_(6)PS_(5)Cl,by coating its surface with a Li-compatible electrolyte Li3OCl having low electronic conductivity.The obtainedLi_(6)PS_(5)Cl@Li_(3)OCl core@shell structure exhibits a synergistic effect.Consequently,compared with the bare Li_(6)PS_(5)Cl,this composite electrolyte exhibits great performance improvements:1)In Li|electrolyte|Li symmetric cells,the critical current density at 30℃gets increased from 0.6 mA cm^(-2)to 1.6 mA cm^(-2),and the lifetime gets prolonged from 320 h to 1400 h at the cycling current of 0.2 mA cm^(-2)or from 10 h to 900 h at the cycling current of 0.5 mA cm^(-2);2)In Li|electrolyte|NCM721 full cells running at 30℃,the cycling capacity at 0.2 C(or 0.5 C)gets enhanced by 20%(or from unfeasible to be feasible)for 100 cycles and the rate capability reaches up to 2 C from 0.2 C;and in full cells running at 60℃,the cycling capacity is increased by 7%at 0.2 C and the rate capability is enhanced to 3.0 C from 0.5 C.The experimental studies and theoretical computations show that the performance enhancements are due to the confined electron penetration and suppressed lithium dendrites growth at theLi_(6)PS_(5)Cl@Li_(3)OCl interface. 展开更多
关键词 Li_(6)PS_(5)Cl Li_(3)OCl Composite solid electrolytes All-solid-state lithium batteries Synergism Core@Shell structure
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Ultra Q:YAG激光治疗黄斑部视网膜前出血17例并文献复习
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作者 肖哲 张胜娟 +3 位作者 赵子琦 兴辰 李成泉 刘志强 《山东大学耳鼻喉眼学报》 2025年第1期130-135,共6页
目的探讨与分析Ultra Q:YAG激光膜切开引流术治疗黄斑部视网膜前出血的疗效。方法回顾性分析17例(17眼)黄斑部视网膜前出血患者,均行Ultra Q:YAG激光膜切开引流术进行治疗,对患者术后随访1个月,观察术后玻璃体腔出血吸收、视力改善、并... 目的探讨与分析Ultra Q:YAG激光膜切开引流术治疗黄斑部视网膜前出血的疗效。方法回顾性分析17例(17眼)黄斑部视网膜前出血患者,均行Ultra Q:YAG激光膜切开引流术进行治疗,对患者术后随访1个月,观察术后玻璃体腔出血吸收、视力改善、并发症发生情况并分析失败原因。结果12眼(70.6%)治疗成功,出血均基本吸收,视力均得到明显改善。治疗失败5眼中其中2眼病程超过30 d,2眼出血形态呈不规则多边形,1眼激光膜切开术后1个月玻璃体积血吸收不佳并行玻璃体切割术。结论Ultra Q:YAG激光治疗黄斑部视网膜前出血有效安全可行。黄斑部视网膜前出血应尽早行Ultra Q:YAG激光治疗以期达到好的治疗效果。 展开更多
关键词 ULTRA Q:YAG激光 黄斑 视网膜前出血 膜切开术 玻璃体切除术
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A Mechanically Robust In-Situ Solidified Polymer Electrolyte for SiO_(x)-Based Anodes Toward High-Energy Lithium Batteries
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作者 Cizhen Luo Huanrui Zhang +8 位作者 chenghao Sun xing chen Wenjun Zhang Pengzhou Mu Gaojie Xu Rongxian Wu Zhaolin Lv Xinhong Zhou Guanglei Cui 《Nano-Micro Letters》 2025年第10期509-524,共16页
Silicon suboxide(SiO_(x),0<x<2)is an appealing anode material to replace traditional graphite owing to its much higher theoretical specific capacity enabling higher-energy-density lithium batteries.Nevertheless,... Silicon suboxide(SiO_(x),0<x<2)is an appealing anode material to replace traditional graphite owing to its much higher theoretical specific capacity enabling higher-energy-density lithium batteries.Nevertheless,the huge volume change and rapid capacity decay of SiO_(x)electrodes during cycling pose huge challenges to their large-scale practical applications.To eliminate this bottleneck,a dragonfly wing microstructure-inspired polymer electrolyte(denoted as PPM-PE)is developed based on in-situ polymerization of bicyclic phosphate ester-and urethane motif-containing monomer and methyl methacrylate in traditional liquid electrolyte.PPM-PE delivers excellent mechanical properties,highly correlated with the formation of a micro-phase separation structure similar with dragonfly wings.By virtue of superior mechanical properties and the in-situ solidified preparation method,PPM-PE can form a 3D polymer network buffer against stress within the electrode particles gap,enabling much suppressed electrode volume expansion and more stabilized solid electrolyte interface along with evidently decreased electrolyte decomposition.Resultantly,PPM-PE shows significant improvements in both cycling and rate performance in button and soft package batteries with SiO_(x)-based electrodes,compared with the liquid electrolyte counterpart.Such a dragonfly wing microstructure-inspired design philosophy of in-situ solidified polymer electrolytes helps facilitate the practical implementation of high-energy lithium batteries with SiO_(x)-based anodes. 展开更多
关键词 High-energy lithium batteries SiO_(x)-based anodes Polymer electrolyte Micro-phase separation structure Cycle performance
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Amino acid substitutions in succinate dehydrogenase complex conferring resistance to the SDHI fungicide pydiflumetofen in Cochliobolus heterostrophus causing southern corn leaf blight
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作者 Jiazhi Sun Bingyun Yang +7 位作者 Lingmin Xia Rui Yang Chaoyang Ding Yang Sun xing chen Chunyan Gu Xue Yang Yu chen 《Journal of Integrative Agriculture》 2025年第7期2670-2685,共16页
Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinat... Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinate dehydrogenase inhibitor(SDHI),has been found as a promising fungicide for the efficient control of SCLB,however,resistance of C.heterostrophus to Pyd has not been studied well.Here,five Pyd-resistant mutants were generated through fungicide adaptation.Sequence alignment analysis revealed that these mutants primarily mutated in ChSdhB and ChSdhD,with three genotypes:ChSdhB^(H277Y),ChSdhB^(I279T)and ChSdhD^(H133Y),exhibiting two distinct categories of resistance:high resistance(HR)and moderate resistance(MR),among which the resistance factors were 214.22 and 44.33-53.67,respectively.These mutants were more pathogenic than the wild-type parental strains,but there was a significant reduction in mycelial growth rate and sporulation in the resistant mutants,indicating a significant fitness cost associated with resistance to Pyd.In addition,this study revealed a positive cross-resistance between Pyd and another SDHI fungicide cyclobutrifluram.However,no cross-resistance was found between Pyd and other classes of fungicides,including prochloraz,fludioxonil,iprodione or pyraclostrobin.Homology modeling and molecular docking further confirmed that point mutations of ChSdhB^(H277Y),ChSdhB^(I279T),and ChSdhD^(H133Y)could reduce binding affinity between Pyd and its target subunits from-74.07,-74.07,-152.52 kcal mol^(-1)to-3.90,-4.95,-9.93 kcal mol^(-1),respectively.These findings not only provided valuable insights for managing SCLB caused by C.heterostrophus,but also enhanced our understanding of molecular mechanism underlying plant pathogen resistance to Pyd. 展开更多
关键词 Cochliobolus heterostrophus pydiflumetofen SDHI resistance resistance mechanism point mutation
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Optimization of a Perforator Nozzle Based on the Constant Velocity of Jet Core
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作者 Aihua Tao Chao Li +3 位作者 Zhijun Jie Yong Zhang xing chen Weili Liu 《Fluid Dynamics & Materials Processing》 2025年第3期645-656,共12页
Hydraulic sandblasting perforation plays a crucial role in the fracturing and reconstruction of unconventional oil and gas reservoirs.The jet nozzle is an essential part of the hydraulic perforation tool.Insufficient ... Hydraulic sandblasting perforation plays a crucial role in the fracturing and reconstruction of unconventional oil and gas reservoirs.The jet nozzle is an essential part of the hydraulic perforation tool.Insufficient penetration depth,caused by excessive jet distances,presents challenges during the perforation process.To overcome this,an optimization design of the nozzle structure is required to enhance the perforation efficiency.In this paper,a computational fluid-dynamic model for conical-cylindrical nozzles has been elaborated.To further improve the rock-breaking efficiency of the jet nozzle,a fillet design is introduced at the nozzle inlet section.The SST k-ωmodel is employed to account for turbulent flow effects in submerged conditions.The results indicate that the nozzle’s geometric parameters greatly influence the flow characteristics.The orthogonal experimental method is employed to optimize the flow channel structure of the nozzle,taking the length of constant velocity core as the evaluation index.The following optimized geometric parameters for the conical-cylindrical nozzle have been determined accordingly:a cylindrical segment diameter of 3.2 mm,a contraction angle of 12°,a contraction segment length of 8 mm,a cylindrical segment length of 6.4 mm,and a fillet radius of 2 mm. 展开更多
关键词 Perforator nozzle field characteristics orthogonal experiment nozzle parameters jet constant velocity core
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Activity of fungicide cyclobutrifuram against Fusarium fujikuroi and mechanism of the pathogen resistance associated with point mutations in FfSdhB,FfSdhC2 and FfSdhD
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作者 Yang Sun Yu Liu +5 位作者 Li Zhou Xinyan Liu Kun Wang xing chen Chuanqing Zhang Yu chen 《Journal of Integrative Agriculture》 2025年第9期3511-3528,共18页
Rice bakanae disease(RBD)is a devastating plant disease caused by Fusarium fujikuroi.This study aimed to evaluate the potential of cyclobutrifuram,a novel succinate dehydrogenase inhibitor(SDHI),to control RBD,and det... Rice bakanae disease(RBD)is a devastating plant disease caused by Fusarium fujikuroi.This study aimed to evaluate the potential of cyclobutrifuram,a novel succinate dehydrogenase inhibitor(SDHI),to control RBD,and determine the risk and mechanism of resistance to cyclobutrifuram in F.fujikuroi.In vitro experiments showed that cyclobutrifuram significantly inhibited mycelial growth and spore germination,and altered the morphology of mycelia and conidia.Treatment with cyclobutrifuram signifcantly decreased mycotoxin production and increased cell membrane permeability in F.fujikuroi.The baseline sensitivity of 72 F.fujikuroi isolates to cyclobutrifuram was determined using mycelial growth and spore germination inhibition assays,which revealed EC50values of 0.0114-0.1304 and 0.0012-0.016μg mL^(-1),with mean EC50values of(0.0410±0.0470)and(0.0038±0.0015)μg mL^(-1),respectively.Pot experiments demonstrated that the protective effect of cyclobutrifluram against F.fujikuroi was more significant than that of phenamacril and azoxystrobin,indicating that cyclobutrifuram is a promising antifungal agent for the control of RBD.Six cyclobutrifuramresistant mutants of F.fujikuroi were obtained via fungicide adaptation.Moreover,these mutants exhibited weaker ftness than their parental isolate and positive cross-resistance with other SDHI fungicides,including pydifumetofen and penfufen;however,no cross-resistance was detected with other classes of fungicides,including phenamacril,fudioxonil,prochloraz,or azoxystrobin.These results indicated that the resistance risk of F.fujikuroi to cyclobutrifuram might be moderate.Sequencing analysis revealed that mutations,including H248D in Ff Sdh B,A83V in Ff Sdh C2,and S106F and E166K in Ff Sdh D,contributed to resistance,which was confrmed by molecular docking and homologous replacement experiments.The results suggest a high potential for cyclobutrifuram to control RBD and a moderate resistance risk of F.fujikuroi to cyclobutrifuram,which are meaningful fndings for the scientifc application of cyclobutrifuram. 展开更多
关键词 Fusarium fujikuroi rice bakanae disease cyclobutrifluram succinate dehydrogenase inhibitors resistance risk and mechanisms
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Heterostructure interface construction of ZnIn_(2)S_(4)nanosheets confined in carbon frameworks for wide-temperature sodium-ion batteries
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作者 Xiue Zhang xing chen +3 位作者 Guodong Li Yongjie Cao Xiao Zhu Yongyao Xia 《Journal of Energy Chemistry》 2025年第8期386-392,共7页
Sodium-ion batteries with ZnIn_(2)S_(4)(ZIS)anodes promise a high capacity and abundant resources.However,their inherent low conductivity,large volume expansion and sluggish Na+diffusion limit the development of the w... Sodium-ion batteries with ZnIn_(2)S_(4)(ZIS)anodes promise a high capacity and abundant resources.However,their inherent low conductivity,large volume expansion and sluggish Na+diffusion limit the development of the wide-temperature sodium storage.This study pioneers a scalable synthesis of hierarchical hollow structural ZIS/C heterostructure through in situ confined growth of ZIS nanosheets in porous hollow carbon spheres(PHCSs)via a hydrothermal method.This unique structure exhibits abundant heterostructures to facilitate charge transport,rich porous structures to promote electrolyte wettability,efficient space utilization to relieve volume expansion,as well as interconnected carbon networks to ensure framework stability.Consequently,ZIS/C exhibits exceptional cycling stability with 92%capacity retention after 1000 cycles.Notably,ZIS/C demonstrates good wide-temperature performance operating at–50∼90°C,especially,at–30°C with a capacity of 208 mA h g^(−1)at 0.3A g^(−1).The full cell of ZIS/C||Na_(3)V_(2)(PO_(4))_(3)exhibits excellent high-rate capability(178 mA h g^(−1)at 6A g^(−1)). 展开更多
关键词 ZnIn_(2)S_(4)nanosheets Confined growth Heterostructure interface Sodium-ion batteries Wide temperature application
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FeCN/MXene as novel heterogeneous electro-Fenton catalysts for the degradation of sulfathiazole:Performance and mechanism investigation
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作者 Huilai Liu Zhihao Li +1 位作者 Defeng Kong xing chen 《Journal of Environmental Sciences》 2025年第8期300-313,共14页
The present study aims to fabricate heterogeneous electro-Fenton(HEF)cathode catalysts for the in-situ generation of H2O2 and the degradation of organic pollutants in water.To achieve this,preparation of Fe and N co-d... The present study aims to fabricate heterogeneous electro-Fenton(HEF)cathode catalysts for the in-situ generation of H2O2 and the degradation of organic pollutants in water.To achieve this,preparation of Fe and N co-doped MXene composites(FeCN/MXene-x,where x represents the loading content of FeCN)and construction of the HEF system for the degradation of sulfathiazole(STZ)were carried out.The characterization results showed that Fe,C and N mainly existed in the form of Fe3C and Fe3N in the FeCN/MXene catalysts,which were favorable for promoting the ORR reaction in the HEF system.Among them,FeCN/MXene-2 exhibited the highest redox electron transfer rate and H2O2 selectivity(86%).The catalytic oxidation mechanism of the FeCN/MXene-2/HEF system was investigated by free radical quenching,electron paramagnetic resonance and frontier orbital theory studies.These studies demonstrated that the main active substances for the degradation of STZ were·OH and 1O2.In addition,the excellent stability and practical performance of the prepared cathodic catalysts were demonstrated by cycling experiments and real water sample tests. 展开更多
关键词 Heterogeneous electro-Fenton process SULFATHIAZOLE FeCN/MXene-x catalysts Oxygen reduction reaction
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Why are the Qinling Mountains Significant to China?
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作者 xing chen Yanjun Shen +3 位作者 Qingyi Mu Panpan Xu Fenghao Duan Jianbing Peng 《Journal of Earth Science》 2025年第1期357-363,共7页
0 INTRODUCTION The Qinling Mountains(QM),located at the geographical center of China,serve as a crucial dividing line between the northern and southern and play a vital role as an ecological security barrier,significa... 0 INTRODUCTION The Qinling Mountains(QM),located at the geographical center of China,serve as a crucial dividing line between the northern and southern and play a vital role as an ecological security barrier,significantly influencing the country's geological,geographical,and ecological landscape(Jia et al.,2023;Peng et al.,2023).The QM stretch from the White Stone Mountain in the northern part of Lintan County,Gansu Province,to the Funiu Mountains in Henan Province in the east. 展开更多
关键词 dividing MOUNTAINS LANDSCAPE
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净化水厂运行现状分析
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作者 邢晨 崔鹏 《黑龙江环境通报》 2025年第6期65-67,共3页
生产给水水质是保障生产稳定的核心要素,与构筑物的设计及原水指标密切相关。本文以某净化水厂为研究对象,基于规模、水源水质、反洗排泥流程、加药种类及用量、供水单位耗电量等分析结果,旨在减少能耗及环境污染,确保处理效果,使水厂... 生产给水水质是保障生产稳定的核心要素,与构筑物的设计及原水指标密切相关。本文以某净化水厂为研究对象,基于规模、水源水质、反洗排泥流程、加药种类及用量、供水单位耗电量等分析结果,旨在减少能耗及环境污染,确保处理效果,使水厂运行更加稳定、高效和环保。 展开更多
关键词 生产给水 节能降耗 水质稳定
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一种Ka频段宽带多波束相控阵的设计
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作者 官劲 孙杰 +2 位作者 杏晨 廖屹 李燚 《光通信研究》 北大核心 2024年第6期103-107,共5页
【目的】全球已步入第5代移动通信技术(5G)和卫星互联网时代,各领域对通信速率和容量的需求激增,传统抛物面和窄带平面相控阵天线系统的应用受到带宽和波束形成数量等因素的限制。文章基于相关产业领域的现状、趋势和宽带多目标的应用需... 【目的】全球已步入第5代移动通信技术(5G)和卫星互联网时代,各领域对通信速率和容量的需求激增,传统抛物面和窄带平面相控阵天线系统的应用受到带宽和波束形成数量等因素的限制。文章基于相关产业领域的现状、趋势和宽带多目标的应用需求,对Ka频段宽带多波束固态相控阵技术展开了研究。【方法】文章从理论上建立并推导了相控阵天线方向图的通用矢量数学仿真模型,研究了相控阵天线的子阵划分、孔径效应和渡越时间等问题,设计了基于阵元级电移相与子阵级光延时相结合的宽带多波束相控阵系统。前端单个集成子阵采用不同材料基板的三维高密度异构瓦式集成方案,极大地提高了子阵集成度;子阵后级采用基于光开关、高精度光纤延迟线和波分复用等技术相结合的光真时延(OTTD)方法,实现了子阵级的多通道延时和多波束合成。【结果】通过对Ka频段宽带多波束接收相控阵系统原理样机进行集成与测试,验证了原理样机克服了孔径渡越时间和波束偏斜等带宽限制问题。原理样机可实现对Ka频段8个独立接收波束的宽角度扫描,每个接收波束的最高数据传输率可达1500 Mbit/s。【结论】测试结果证明,文章所提系统具有集成度高、带宽大和可形成多个独立波束等优势。研究成果将有助于促进宽带多波束固态相控阵的进一步发展,为Ka频段宽带多目标相控阵的后续工程化和产品化奠定了理论和实践基础。 展开更多
关键词 固态相控阵 KA频段 宽带 多波束 光真时延
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北京市不动产登记运维问题智能分类
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作者 董承玮 李云汉 +2 位作者 邢晨 肖曼丽 刘世凡 《北京测绘》 2024年第12期1670-1676,共7页
为提高北京市不动产登记的日常运维效率,解决人工处理效率低下、响应时间长的问题,本文提出一种基于变换器的双向编码器表示模型(BERT)的运维问题自动分类方法。首先使用BERT模型提取运维问题文本的上下文语义特征,然后利用全局最大池... 为提高北京市不动产登记的日常运维效率,解决人工处理效率低下、响应时间长的问题,本文提出一种基于变换器的双向编码器表示模型(BERT)的运维问题自动分类方法。首先使用BERT模型提取运维问题文本的上下文语义特征,然后利用全局最大池化技术提取文本的关键类别特征,最后通过Soft Max函数计算各类别的概率,并选择概率最大的类别作为分类结果。实验结果表明,本文方法的宏平均精确率(MP)、宏平均召回率(MR)和宏平均F1值均大于93%,显著优于常用的文本分类技术,充分证明了该方法的有效性,对构建不动产登记智慧运维体系具有一定的参考意义。 展开更多
关键词 不动产 智能分类 预训练语言模型 基于变换器的双向编码器表示模型(BERT) 数据集构建
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Olympics in the Copyright Community 5th China International Copyright Expo held in Chendu
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作者 xing chen 《China & The World Cultural Exchange》 2014年第11期35-36,共2页
From September 1 7 to 1 9, the 5th China International Copy-right Expo (CICE) took place in Chengdu, capital city of Sichuan province. CICE, dubbed as "copy-right Olympics", featured the theme of" copyright in... From September 1 7 to 1 9, the 5th China International Copy-right Expo (CICE) took place in Chengdu, capital city of Sichuan province. CICE, dubbed as "copy-right Olympics", featured the theme of" copyright innovation and development" this year. i2 thematic events were held during the expo, 展开更多
关键词 奥运会 博览会 版权 成都 国际 中国 四川省 世博会
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