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Tetragonal-pseudocubic phase boundaries and octahedral order-disorder tilting transitions facilitate high piezoelectric performance in Bi1/2Na1/2TiO3-based single crystals
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作者 Jialin Niu Yongxing Wei +10 位作者 Yanghuan Deng Changpeng Guan Changqing jin Leiyang Zhang Ruiyi jing Zhong Yang Zengyun Jian Zhonghua Dai Zengzhe Xia Roman G.Burkovsky li jin 《Advanced Powder Materials》 2026年第1期29-38,共10页
High-performance lead-free piezoelectric single crystals are urgently needed for next-generation actuators and transducers.In this study,we reveal that a compositionally driven tetragonal-pseudocubic(T-PC)phase bounda... High-performance lead-free piezoelectric single crystals are urgently needed for next-generation actuators and transducers.In this study,we reveal that a compositionally driven tetragonal-pseudocubic(T-PC)phase boundary,in conjunction with an octahedral order-disorder tilting transition,significantly enhances the piezoelectric response in Nb^(5+)-substitution(Bi_(0.48)Na_(0.425)K_(0.055)Ba_(0.04))(Ti_(0.98)Nb_(0.02))O_(3)(BNKBT-2Nb)single crystals.The crystal achieves an outstanding piezoelectric coefficient of d33=662 pC/N at room temperature.In situ X-ray diffraction confirms an electric field-induced transition from the PC to T phase.Atomic-resolution HADDF-STEM analysis reveals an increase in the c/a ratio(c/a>1.01)on the local scale and ordered octahe-dral tilting of the a^(0)a^(0)c+type driven by the poling field.The single crystals exhibit excellent piezoelectric per-formance over a broad temperature range,achieving a peak d_(33) of 920 pC/N at approximately 92℃.Furthermore,the polar states exhibit a pronounced frequency dependence near the depolarization temperature.These findings provide critical insight into the structure-property relationship and offer a promising pathway for designing advanced lead-free piezoelectric crystals for functional electromechanical applications. 展开更多
关键词 Single crystals Lead-free Phase boundary Piezoelectricity Oxygen octahedra tilts
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基于Simulink与FPGA的16APSK高速解调系统
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作者 夏创 周澳 +1 位作者 李劲 罗义军 《仪表技术与传感器》 北大核心 2025年第12期70-76,共7页
随着低轨卫星网络持续建设,需优化链路速率降低传输延迟,以实现卫星与地面网络的高效融合。同时针对低轨卫星高速运动引发的多普勒频移,基于Simulink,在环路带有延迟单元的情况下,完成高速并行16APSK解调系统的仿真。通过带有高速时钟的... 随着低轨卫星网络持续建设,需优化链路速率降低传输延迟,以实现卫星与地面网络的高效融合。同时针对低轨卫星高速运动引发的多普勒频移,基于Simulink,在环路带有延迟单元的情况下,完成高速并行16APSK解调系统的仿真。通过带有高速时钟的FPGA,实现了多路并行的系统硬件设计。在设计中提高数据量化精度,将解调后的信号导出至MATLAB,与前期仿真结果进行对比,验证了硬件设计的正确性。为测试系统性能,不断优化系统时序,并分析系统环路触发器级数对误码率及建立时间裕量的影响规律。 展开更多
关键词 SIMULINK 解调系统 FPGA 触发器
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苗药糖宁通络片治疗糖尿病前期患者的多中心、随机、双盲、安慰剂对照试验
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作者 赵能江 李津 +15 位作者 夏文 张智海 袁乔英 杨娟 陈杰 杨倩 王世东 孙新宇 王秀阁 周玉森 钱锐 赵进东 田国庆 陆灏 黄延芹 杨叔禹 《中医杂志》 北大核心 2026年第2期166-172,共7页
目的观察苗药糖宁通络片治疗糖尿病前期患者的有效性和安全性,为糖尿病早期干预提供依据。方法采用随机、双盲、安慰剂对照的试验设计,纳入全国14家医院180例糖尿病前期患者,分为糖宁通络组与安慰剂组各90例。糖宁通络组采用糖宁通络片... 目的观察苗药糖宁通络片治疗糖尿病前期患者的有效性和安全性,为糖尿病早期干预提供依据。方法采用随机、双盲、安慰剂对照的试验设计,纳入全国14家医院180例糖尿病前期患者,分为糖宁通络组与安慰剂组各90例。糖宁通络组采用糖宁通络片+生活方式干预,安慰剂组给与安慰剂+生活方式干预,两组疗程均为12周。治疗后观察主要疗效指标(从首次用药开始12周内进展为2型糖尿病的发病率)、次要疗效指标[包括治疗前后体重、体重指数(BMI)、腰臀比、空腹血糖(FPG)、餐后2 h血糖(2hPG)、糖化血红蛋白(HbA1c)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、尿酸(UA)、尿白蛋白/肌酐比值(UACR)、胰岛素抵抗指数(HOMA-IR)、0~120分血糖曲线下面积(AUC_(0~120 min))];评价肝肾功能等安全性指标;采用多因素Logistic回归分析和多元线性回归分析评价糖宁通络片对各结局指标的影响;并根据BMI进行探索性亚组分析。结果糖宁通络组和安慰剂组分别有85例和79例完成研究。治疗3个月后,糖宁通络组和安慰剂组2型糖尿病发病率分别为4.71%(4/85)和13.92%(11/79),差异有统计学意义(P<0.05)。Logistic回归分析提示,糖宁通络片能降低糖尿病发生风险74.4%[OR=0.256,95%CI(0.066,0.812),P<0.05]。两组患者次要疗效指标及安全性指标比较差异均无统计学意义(P>0.05)。亚组分析显示,在BMI<24 kg/m^(2)亚组患者中,糖宁通络组的FPG和AUC_(0~120 min)较安慰剂组降低(P<0.05)。结论糖宁通络片可降低糖尿病前期患者进展为2型糖尿病的发病率,具有较好的安全性,且在BMI<24 kg/m2的患者中降糖效果更佳。 展开更多
关键词 糖尿病前期 2型糖尿病 糖宁通络片 苗药 随机对照试验
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超高真空蒸发制备Pd/Ti吸气薄膜的工艺优化与性能研究
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作者 李伟 李进 +2 位作者 李宇龙 王旭迪 曹青 《真空科学与技术学报》 北大核心 2026年第1期76-83,共8页
Pd/Ti吸气剂薄膜作为超高真空系统中重要的真空维持材料,具有激活温度低、抽速快等优点。针对薄膜制备过程中蒸发源热变形导致的镀膜均匀性问题,研究采用COMSOL多物理场仿真分析了靶丝热变形行为,提出了“石英玻璃棒+变距弹簧靶丝”的... Pd/Ti吸气剂薄膜作为超高真空系统中重要的真空维持材料,具有激活温度低、抽速快等优点。针对薄膜制备过程中蒸发源热变形导致的镀膜均匀性问题,研究采用COMSOL多物理场仿真分析了靶丝热变形行为,提出了“石英玻璃棒+变距弹簧靶丝”的复合结构设计,将Pd丝和Ti丝的径向最大热变形量分别降至0.0216 mm和0.0494 mm,相比直丝结构分别提升约303倍和63倍。自主设计搭建了超高真空蒸发镀膜系统,系统研究了Pd/Ti薄膜的蒸发工艺参数,确定了Ti丝45A/60 min、Pd丝18 A/2-10 min的最佳工艺条件。SEM分析表明薄膜呈典型柱状生长结构,Pd覆层连续均匀覆盖Ti底层。镀膜后系统极限真空达到1.41×10^(-8)Pa,真空维持性能显著提升。定压法吸氢测试结果显示,基底材料对吸气性能影响显著,无氧铜箔基底的稳定抽速(0.006 L/(s·cm^(2)))优于工业钛箔基底(0.002 L/(s·cm^(2)));Pd层厚度存在最优值,约50 nm厚度时吸气性能最佳,抽速达0.005 L/(s·cm^(2))。研究为Pd-Ti薄膜吸气剂的工程化制备提供了重要的技术支撑和数据基础。 展开更多
关键词 非蒸散型吸气剂 Pd/Ti薄膜 真空蒸镀 蒸发源结构优化 吸气性能测试
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Ancient genomic analysis of a Chinese hereditary elite from the Northern and Southern Dynasties 被引量:1
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作者 Yao Yu Xiaomin Yang +12 位作者 Daiyun liu Panxin Du e Hailiang Meng Zixiao Huang Jianxue Xiong Yi Ding Xiaoying Ren Edward Allen Hui Wang Sheng Han li jin Chuan-Chao Wang Shaoqing Wen 《Journal of Genetics and Genomics》 2025年第4期473-482,共10页
China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic ... China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic groups,with limited research on the genetic formation of the hereditary elite family,especially considering their abundant archaeological record and clear material identity.In this study,we obtain the ancient genome of a hereditary elite family,Gao Bin(高宾,503 AD–572 AD),at 0.6473-fold coverage with 475,132 single-nucleotide polymorphisms(SNPs)on the 1240k panel.His mitochondrial haplogroup belongs to Z4 and Y-haplogroup to O1a1a2b-F2444∗.The genetic profile of Gao Bin is most similar to that of the northern Han Chinese.He can be modeled as deriving all his ancestry from Late Neolithic to Iron Age Yellow River farmers without influence from Northeast Asia,Korea,or the Mongolian Plateau.Our study sheds light on the genetic formation of hereditary elite families in the context of the Southern and Northern Dynasties ethnic integration. 展开更多
关键词 Ancient DNA Hereditary elite Population admixture Bohai Gao Branch Korean Goguryeo origin
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Towards high stiffness and ductility—The Mg-Al-Y alloy design through machine learning 被引量:1
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作者 Zhiyuan liu Tianyou Wang +5 位作者 li jin Jian Zeng Shuai Dong Fenghua Wang Fulin Wang Jie Dong 《Journal of Materials Science & Technology》 2025年第18期194-203,共10页
In traditional trial-and-error method,enhancing the Young's modulus of magnesium alloys while maintaining a favorable ductility has consistently been a challenge.It is a need to explore more efficient and expedite... In traditional trial-and-error method,enhancing the Young's modulus of magnesium alloys while maintaining a favorable ductility has consistently been a challenge.It is a need to explore more efficient and expedited methods to design magnesium alloys with high modulus and ductility.In this study,machine learning(ML)and assisted microstructure control methods are used to design high modulus magnesium alloys.Six key features that influence stiffness and ductility have been extracted in this ML model based on abundant data from literature sources.As a result,predictive models for Young's modulus and elongation are established,with errors<2.4%and 4.5%through XGBoost machine learning model,respectively.Within the given range of six features,the magnesium alloys can be fabricated with the Young's modulus exceeding 50 GPa and an elongation surpassing 6%.As a validation,Mg-Al-Y alloys were experimentally prepared to meet the criteria of six features,achieving Young's modulus of 51.5 GPa,and the elongation of 7%.Moreover,the SHapley Additive exPlanation(SHAP)is introduced to boost the model interpretability.This indicates that balancing the volume fraction of reinforcement,the most important feature,is key to achieve Mg-Al-Y alloys with high Young's modulus and favorable elongation through the two models.Enhancing reinforcement dispersion and reducing the size of reinforcement and grain can further improve the elongation of high-stiffness Mg alloy. 展开更多
关键词 Image analysis Machine learning Al_(2)Y Young’s modulus
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CBL结合思维导图教学法在超声医学教学中的应用效果
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作者 韦馨 郑红 +5 位作者 周柱玉 胡德军 李金 何糠 冯佳 郑研 《卫生职业教育》 2026年第5期65-69,共5页
目的探讨CBL结合思维导图教学法在超声医学教学中的应用效果。方法采用方便抽样法选取2024年5—12月在德阳市人民医院超声科实习的40名实习生为研究对象,应用随机数字表法分为对照组和观察组,每组20名。对照组采用CBL教学法,观察组采用... 目的探讨CBL结合思维导图教学法在超声医学教学中的应用效果。方法采用方便抽样法选取2024年5—12月在德阳市人民医院超声科实习的40名实习生为研究对象,应用随机数字表法分为对照组和观察组,每组20名。对照组采用CBL教学法,观察组采用CBL结合思维导图教学法。带教后,比较两组考试成绩、批判性思维评分和教学满意度。结果观察组理论知识和实践技能考试成绩、批判性思维评分、教学满意度均高于对照组,差异有统计学意义(P<0.05)。结论CBL结合思维导图教学法可显著提高实习生的理论知识水平、实践能力和批判性思维能力,并提升教学满意度,值得推广。 展开更多
关键词 CBL教学法 思维导图 超声医学 实习生
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EGFR、STAT3表达与胃癌上皮-间质转化的关系
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作者 曾庆松 李进 +2 位作者 朱海超 潘婷婷 徐艳琴 《实用癌症杂志》 2026年第2期179-182,186,共5页
目的分析EGFR、STAT3表达与胃癌上皮-间质转化的关系。方法收集102例胃癌患者的临床资料进行回顾性研究,比较胃癌组织与癌旁组织中EGFR、STAT3的表达情况,分析EGFR、STAT3表达与胃癌临床病理特征的关系及与胃癌上皮-间质转化标志物E-cad... 目的分析EGFR、STAT3表达与胃癌上皮-间质转化的关系。方法收集102例胃癌患者的临床资料进行回顾性研究,比较胃癌组织与癌旁组织中EGFR、STAT3的表达情况,分析EGFR、STAT3表达与胃癌临床病理特征的关系及与胃癌上皮-间质转化标志物E-cadherin、Vimentin的关系。结果两组EGFR、STAT3表达比较,差异有统计学意义,胃癌组织EGFR、STAT3阳性表达率均高于癌旁组织(χ_(2)=15.760,P<0.001、χ_(2)=20.203,P<0.001),差异有统计学意义。不同性别、年龄、肿瘤直径、肿瘤部位患者癌组织中EGFR、STAT3的表达比较,差异无统计学意义(P>0.05),不同肿瘤分化、TNM分期、淋巴结转移患者癌组织中EGFR、STAT3的表达比较,差异有统计学意义,EGFR、STAT3表达可能与肿瘤分化、TNM分期、淋巴结转移有关,低分化、Ⅲ+Ⅳ期、淋巴结转移患者癌组织中EGFR、STAT3的阳性表达率高于高中分化、Ⅰ+Ⅱ期、无淋巴结转移患者,差异有统计学意义(P<0.05)。胃癌组织中EGFR、STAT3的表达可能与上皮-间质转化标志物E-cadherin、Vimentin有关。结论EGFR、STAT3在胃癌组织中呈高表达,二者可能与肿瘤分化、TNM分期、淋巴结转移、上皮-间质转化有关。 展开更多
关键词 胃癌 EGFR STAT3 上皮-间质转化
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重心插值配点法的研究现状
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作者 李金 孙鹏航 +1 位作者 王兆清 赵晓伟 《山东建筑大学学报》 2026年第1期111-118,共8页
近年来,重心插值配点法越来越受到工程和数学工作者的重视。目前该方法已被用于常微分方程初-边值问题、积分、积分-微分方程、二阶偏微分方程、波动方程、热传导方程、非线性随机微分方程高阶常微分和偏微分方程等线性和非线性问题的... 近年来,重心插值配点法越来越受到工程和数学工作者的重视。目前该方法已被用于常微分方程初-边值问题、积分、积分-微分方程、二阶偏微分方程、波动方程、热传导方程、非线性随机微分方程高阶常微分和偏微分方程等线性和非线性问题的求解。文章综述了近年来重心插值配点法的研究进展,论述一维和二维重心插值及其微分矩阵的定义和性质,梳理国内外关于重心插值公式、重心有理插值和数值求解方法的研究进展,探讨重心插值配点法在三维问题和分数阶微分方程求解中的应用,总结重心插值配点法的优点、局限性,并展望重心插值配点法未来的研究方向。 展开更多
关键词 重心插值配点法 有理插值 误差估计 分数阶
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护生实习后期工作投入现状及其影响因素
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作者 刘丽杰 李进 +2 位作者 覃利英 邹玉珺 伍敏玲 《循证护理》 2026年第2期391-396,共6页
目的:调查护生实习后期工作投入现状及其影响因素。方法:采用便利抽样法选取2025年1月—2月广州市某三级甲等综合医院的180名实习护生为研究对象,采用一般资料调查表、工作投入量表、工作倦怠量表、一般自我效能感量表、任务负荷指数、... 目的:调查护生实习后期工作投入现状及其影响因素。方法:采用便利抽样法选取2025年1月—2月广州市某三级甲等综合医院的180名实习护生为研究对象,采用一般资料调查表、工作投入量表、工作倦怠量表、一般自我效能感量表、任务负荷指数、护生临床学习环境量表进行横断面调查。结果:回收有效问卷167份,有效回收率为92.78%(167/180)。实习护生后期工作投入量表总分为(35.49±8.62)分。多因素分析结果显示,学历、毕业后从事护理工作意愿、工作倦怠、一般自我效能感、任务负荷、临床学习环境是护生实习后期工作投入的影响因素(P<0.05)。结论:实习护生实习后期工作投入水平处于中等水平,影响因素较多,建议护理教育者优化临床教学策略,促进实习护生在实习后期维持良好的工作投入水平。 展开更多
关键词 实习护生 后期 工作投入 工作倦怠 一般自我效能感 任务负荷 临床学习环境 影响因素 护理
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Thermal-responsive Photonic Crystals based on Physically Cross-linked Inverse Opal Nanocomposite Hydrogels 被引量:1
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作者 ZHENG Hang li jin +3 位作者 SONG Weizheng HE Guangyao WANG Yifeng CHEN Yanjun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2021年第2期289-296,共8页
A thermal-responsive photonic crystal material was fabricated by forming an inverse opal nanocomposite hydrogel of poly(N-isopropylacrylamide)(IONHPNIPAm)within the interstitial space of a polystyrene photonic crystal... A thermal-responsive photonic crystal material was fabricated by forming an inverse opal nanocomposite hydrogel of poly(N-isopropylacrylamide)(IONHPNIPAm)within the interstitial space of a polystyrene photonic crystal template.In IONHPNIPAm,PNIPAm were physically cross-linked with two kinds of nanoparticles(carbon dots and laponite clays).The integration of carbon dots and laponite clays for physical crosslinking endowed IONHPNIPAm sufficient strength and self-healing property.IONHPNIPAm films can be completely peeled from the substrates to be utilized as an independent photonic crystal material.The structural color and optical diffraction of the IONHPNIPAm exhibits a rapid reversible change in response to external thermal stimuli due to its physical cross-linking feature.Moreover,the IONHPNIPAm shows clear fluorescence due to the introduction of carbon dots,which enables a convenient way for chemical detection(such as the detection of silver ions).This stimuli-responsive photonic crystal materials based on physically cross-linked inverse opal nanocomposite hydrogels with fast response and good mechanical stability are promising for applications in the fields of smart optical detectors,thermal-responsive sensors and chemical detectors. 展开更多
关键词 photonic crystals inverse opal physical cross-linking thermal-responsive nanocomposite hydrogel
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自主话语体系建设背景下的学前儿童语言教育研究
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作者 霍力岩 杜宝杰 +1 位作者 李金 魏灿星 《中华女子学院学报》 2026年第1期92-99,共8页
在当前西方语言发展理论及其教育模式影响下,我国学前儿童语言教育中本土文化语境与语言智慧未能得到足够重视,弱化了其在推动儿童文化认同与精神成长方面的作用。本研究以建立中国学前儿童语言教育的自主话语体系为目标,展开系统性的... 在当前西方语言发展理论及其教育模式影响下,我国学前儿童语言教育中本土文化语境与语言智慧未能得到足够重视,弱化了其在推动儿童文化认同与精神成长方面的作用。本研究以建立中国学前儿童语言教育的自主话语体系为目标,展开系统性的理论反思与实践探索。通过哲学分析,融合“言为心声”“文以载道”“道器合一”等传统思想,提出一种整合价值、实践与关系的语言教育观。借助批判性比较研究,对6份国内外早期语言发展纲要进行并置分析,揭示西方技能导向模式的局限以及中国文化回应型路径的必要性。在此基础上,构建了以价值取向、关键经验与发展路径为基本维度的理论框架,形成包含3个维度、10项核心要素及29项行为指标的完整体系。该体系并非静态行为清单,而是一个由文化价值引领、关键经验生成与实践路径支撑相互作用的动态文化生态系统,旨在为构建具有中国特色的学前儿童语言教育范式提供学理依据与实践参照。 展开更多
关键词 自主话语体系 学前儿童 语言教育 文化认同
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基于机器视觉的牡丹种子筛选机设计
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作者 徐君鹏 李金 +3 位作者 时磊 王宇 贾文庆 陈韵 《河南科技学院学报(自然科学版)》 2026年第1期65-74,共10页
目的针对目前牡丹种子筛选耗费人力的问题,设计一种基于机器视觉技术的自动化牡丹种子筛选机.方法筛选机主要有供料系统、传输系统、图像采集系统和控制系统四大部分组成,以牡丹种子外表面为研究对象,通过图像处理技术,把目标区域和背... 目的针对目前牡丹种子筛选耗费人力的问题,设计一种基于机器视觉技术的自动化牡丹种子筛选机.方法筛选机主要有供料系统、传输系统、图像采集系统和控制系统四大部分组成,以牡丹种子外表面为研究对象,通过图像处理技术,把目标区域和背景实现有效分割,筛选出裂纹种子和优质种子.结果筛选设备可以实现1.5粒/s牡丹种子的检测速度,与传统人工检测0.2粒/s的检测速度相比,提升6倍.结论牡丹种子筛选机替代人工筛选牡丹种子可以解决人工检测耗费人力的问题. 展开更多
关键词 牡丹种子 机器视觉 筛选机构 分割
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山东省14例输入性卵形疟原虫wallikeri亚种的鉴定 被引量:6
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作者 李瑾 魏庆宽 +8 位作者 徐超 肖婷 黄炳成 孔祥礼 王龙江 王用斌 许艳 尹昆 孙慧 《中国人兽共患病学报》 CAS CSCD 北大核心 2018年第11期991-995,共5页
目的对山东省14例输入性卵形疟原虫wallikeri亚种进行鉴定分析。方法收集14例输入性疟疾病例,进行快速疟疾诊断试纸条检测(RDT)、血涂片镜检、NP-1993常规巢式PCR鉴定和卵形疟原虫wallikeri(P.ovale wallikeri)亚种的特异性PCR检测。PC... 目的对山东省14例输入性卵形疟原虫wallikeri亚种进行鉴定分析。方法收集14例输入性疟疾病例,进行快速疟疾诊断试纸条检测(RDT)、血涂片镜检、NP-1993常规巢式PCR鉴定和卵形疟原虫wallikeri(P.ovale wallikeri)亚种的特异性PCR检测。PCR扩增产物测序后,进行Blast比对分析。结果 14例患者RDT检测结果:泛疟原虫(非恶性疟)阳性12例,阴性2例;镜检结果,13例卵形疟原虫,1例间日疟原虫;NP-1993常规巢式PCR结果,14例样本4种疟原虫引物扩增结果均为阴性。P.ovale wallikeri亚种的特异性PCR检测结果:14例样本均能扩增到P.ovale wallikeri亚种特异性条带780bp。Blast分析测序结果,检索结果为P.ovale wallikeri亚种。结论 14例镜检阳性、NP-1993常规巢式PCR检测阴性的输入性疟疾病例均确诊为P.ovale wallikeri亚种感染。 展开更多
关键词 疟疾 卵形疟原虫wallikeri亚种 巢式PCR
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High-field ferroelectric dynamics and phase evolution in lithium-doped silver niobate ceramics
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作者 Wenjing Shi Leiyang Zhang +6 位作者 Pingji Ge Ye Tian Ruiyi jing Denis Alikin Vladimir Shur Xiaoqin Ke li jin 《Journal of Materials Science & Technology》 2025年第33期317-328,共12页
The structural phase transitions and ferroelectric dynamics of lead-free AgNbO_(3)have attracted consid-erable attention owing to their potential in energy-storage device applications.Here,we examine the impact of Li+... The structural phase transitions and ferroelectric dynamics of lead-free AgNbO_(3)have attracted consid-erable attention owing to their potential in energy-storage device applications.Here,we examine the impact of Li+doping on the phase transitions and polarization behavior of(Ag_(1-x)Li_(x))NbO_(3)(x=0-7%)ceramics through comprehensive dielectric and ferroelectric analyses.Rietveld refinement reveals a Li+-induced phase transition from Pbcm to R3c,with x=5%and x=6%compositions near the morphotropic phase boundary(MPB).Dielectric anomalies identify key characteristic temperatures,supporting the con-struction of a low-field phase diagram.High-field studies uncover a direct relationship between phase structure and polarization behavior,culminating in a high-field phase diagram.Near-MPB compositions exhibit distinct structural states,elucidating the mechanisms of reversible and irreversible phase transi-tions.This work provides a comprehensive explanation of the evolution of hysteresis loop profiles,capturing their progression from double hysteresis loops to square loops and their subsequent reversion to double loops under varying electric field and temperature conditions.These temperature-composition(T-x)and temperature-electric field(T-E)phase diagrams provide a robust framework for understanding phase evolution,offering critical insights into optimizing AgNbO_(3)-based ceramics for advanced functional applications. 展开更多
关键词 AgNbO_(3) LEAD-FREE Silver niobate ANTIFERROELECTRIC Phase translation CERAMICS
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New Opportunities,Challenges,and Strategies for Educational Evaluation Reform in the Era of Artificial Intelligence
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作者 li jin Hua Zhang 《Journal of Contemporary Educational Research》 2025年第1期66-73,共8页
Under the rapid impetus of artificial intelligence(AI)technology,human society is stepping into the age of intelligence at an unprecedented speed.A new generation of information technology such as AI is not only a new... Under the rapid impetus of artificial intelligence(AI)technology,human society is stepping into the age of intelligence at an unprecedented speed.A new generation of information technology such as AI is not only a new engine of economic development,but also a gas pedal of social development,which has had a profound impact on the field of education.In the face of the opportunities and challenges of the AI era,it is particularly urgent to build a scientific and reasonable education evaluation system.This paper combines the context of the times with the new technology of AI to discuss the opportunities,challenges,and implementation strategies of educational evaluation reform in the era of AI,with a view to providing references for the construction of the educational evaluation system and the development of high-quality education in the new era. 展开更多
关键词 Artificial intelligence Education evaluation reform New policy Formative evaluation Value-added evaluation Multiple evaluation
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A multi-ancestry GWAS meta-analysis of facial features and its application in predicting archaic human features
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作者 Siyuan Du Jieyi Chen +21 位作者 Jiarui li Wei Qian Sijie Wu Qianqian Peng Yu liu Ting Pan Yi li Sibte Syed Hadi jingze Tan Ziyu Yuan Jiucun Wang Kun Tang Zhuo Wang Yanqin Wen Xinran Dong Wenhao Zhou Andres Ruiz-linares Yongyong Shi li jin Fan liu Manfei Zhang Sijia Wang 《Journal of Genetics and Genomics》 2025年第4期513-524,共12页
Facial morphology,a complex trait influenced by genetics,holds great significance in evolutionary research.However,due to limited fossil evidence,the facial characteristics of Neanderthals and Denisovans have remained... Facial morphology,a complex trait influenced by genetics,holds great significance in evolutionary research.However,due to limited fossil evidence,the facial characteristics of Neanderthals and Denisovans have remained largely unknown.In this study,we conduct a large-scale multi-ethnic meta-analysis of the genome-wide association study(GWAS),including 9674 East Asians and 10,115 Europeans,quantitatively assessing 78 facial traits using 3D facial images.We identify 71 genomic loci associated with facial features,including 21 novel loci.We develop a facial polygenic score(FPS)that enables the prediction of facial features based on genetic information.Interestingly,the distribution of FPSs among populations from diverse continental groups exhibits relevant correlations with observed facial features.Furthermore,we apply the FPS to predict the facial traits of seven Neanderthals and one Denisovan using ancient DNA and align predictions with the fossil records.Our results suggest that Neanderthals and Denisovans likely share similar facial features,such as a wider but shorter nose and a wider endocanthion distance.The decreased mouth width is characterized specifically in Denisovans.The integration of genomic data and facial trait analysis provides valuable insights into the evolutionary history and adaptive changes in human facial morphology. 展开更多
关键词 Genome-wide association study Multi-ethnic meta-analysis Facial morphology Facial polygenic score Ancient DNA Archaic human
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Shock index and early warning score in liver cancer rupture shock
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作者 Ji-Fen Ma li jin +3 位作者 ling Sha Hong-Fang li Xiang-Yun Qian Hai-Yan Wang 《World Journal of Gastrointestinal Surgery》 2025年第10期246-254,共9页
BACKGROUND Primary liver cancer is a globally prevalent malignancy,with China accounting for approximately 55%of new cases,and is linked to hepatitis B,aflatoxin,and cirrhosis.Its rupture with hemorrhagic shock is a l... BACKGROUND Primary liver cancer is a globally prevalent malignancy,with China accounting for approximately 55%of new cases,and is linked to hepatitis B,aflatoxin,and cirrhosis.Its rupture with hemorrhagic shock is a lethal complication with high mortality,and traditional triage struggles with timely risk stratification,necessitating better tools,such as the integrated shock index(SI)-early warning score(EWS).AIM To study and analyze the combined effect of the SI and EWS in primary liver cancer patients with ruptured hemorrhage and shock.METHODS In total,118 patients who visited the Emergency Department of Nantong Third People's Hospital from January 2023 to December 2024 were selected and randomly divided into a control group(59 patients who received routine emergency treatment)and an observation group(59 patients who received condition assessment and intervention by combining the SI and EWS based on routine emergency treatment).The clinical treatment outcomes,respiratory function indicators,serological indicators,complications,and satisfaction with emergency intervention before and after the emergency intervention were compared between the two groups.RESULTS The emergency,triage,waiting,and hemostasis times,as well as hospital stay were shorter in the observation group than in the control group(P<0.05).After 48 hours of emergency intervention,blood oxygen saturation and partial pressure of oxygen in the observation group were higher than those in the control group(P<0.05).Seven days after emergency intervention,the hemoglobin,prealbumin,and albumin levels were higher in the observation group than in the control group(P<0.05).The complication rate in the observation group was 3.39%,lower than that in the control group(13.56%;P<0.05).Satisfaction with emergency intervention in the observation group was 94.92%,higher than 83.05%in the control group(P<0.05).CONCLUSION The combined application of the SI and EWS in patients with primary liver cancer rupture,hemorrhage,and shock can significantly shorten emergency treatment time,improve respiratory function and serological indicators,reduce the incidence of complications,and enhance patient satisfaction with emergency interventions,with higher clinical treatment efficiency and quality.Therefore,it is worthy of promotion and application. 展开更多
关键词 Primary liver cancer Rupture hemorrhage Shock index Early warning score system COMPLICATIONS
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Natural selection shaped the protective effect of the mtDNA lineage against obesity in Han Chinese populations
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作者 Ziwei Chen Lu Chen +8 位作者 jingze Tan Yizhen Mao Meng Hao Yi li Yi Wang jinxi li Jiucun Wang li jin Hong-Xiang Zheng 《Journal of Genetics and Genomics》 2025年第4期539-548,共10页
Mitochondria play a key role in lipid metabolism,and mitochondrial DNA(mtDNA)mutations are thus considered to affect obesity susceptibility by altering oxidative phosphorylation and mitochondrial function.In this stud... Mitochondria play a key role in lipid metabolism,and mitochondrial DNA(mtDNA)mutations are thus considered to affect obesity susceptibility by altering oxidative phosphorylation and mitochondrial function.In this study,we investigate mtDNA variants that may affect obesity risk in 2877 Han Chinese individuals from 3 independent populations.The association analysis of 16 basal mtDNA haplogroups with body mass index,waist circumference,and waist-to-hip ratio reveals that only haplogroup M7 is significantly negatively correlated with all three adiposity-related anthropometric traits in the overall cohort,verified by the analysis of a single population,i.e.,the Zhengzhou population.Furthermore,subhaplogroup analysis suggests that M7b1a1 is the most likely haplogroup associated with a decreased obesity risk,and the variation T12811C(causing Y159H in ND5)harbored in M7b1a1 may be the most likely candidate for altering the mitochondrial function.Specifically,we find that proportionally more nonsynonymous mutations accumulate in M7b1a1 carriers,indicating that M7b1a1 is either under positive selection or subject to a relaxation of selective constraints.We also find that nuclear variants,especially in DACT2 and PIEZO1,may functionally interact with M7b1a1. 展开更多
关键词 Mitochondrial DNA OBESITY Association analysis Natural selection Selective pressure
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Construction of problem list coding system for the whole life cycle of sea island supervision
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作者 WANG Na JI Dawei +5 位作者 li jin ZHAO jinxia ZHENG Fangyuan WANG jin TAN Lun GAO Yikang 《Marine Science Bulletin》 2025年第1期50-65,共16页
The code of the list of sea and island problems is the unique identification code of the regulatory files,which is accompanied by the whole life cycle of the regulatory"discovery,verification and disposal".S... The code of the list of sea and island problems is the unique identification code of the regulatory files,which is accompanied by the whole life cycle of the regulatory"discovery,verification and disposal".Standardized coding of problems found by supervision and tracking and recording the whole life cycle of supervision can quickly guide supervisors to find problems,identify problems,initiate responses and carry out follow-up disposal,which is a reflection of whole-process management of supervision.Combining with sea and island regulatory systems and mechanisms,combed the supervision business flow,divides the supervision link,based on the existing coding system,from the Angle of supervision refinement,puts forward a whole lifetime oriented regulatory system of sea and island issues list for coding,coding through to find and stop and disposal of the three links all process application scenarios,The implementation of the whole business"one code"association,the whole process of"one code"management,practice verification shows the effectiveness of the method,compared with the original coding rules for the supervision of all links and results reflect more intuitive,comprehensive,can be better applied to the practice of supervision. 展开更多
关键词 Marine supervision sea and island supervision coding fine regulation
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