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High Power Laser Science and Engineering 2024年第3期12卷 1-8页

作者： lian Zhou Haipeng Lou Zejiang Deng Xiong Qin Jiayi Pan Yuanfeng Di Chenglin Gu Daping Luo wenxue li State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghaiChina Joint Research Center of light Manipulation Science and Photonic Integrated Chip of East China Normal University and Shandong Normal University East China Normal UniversityShanghaiChina

The mid-infrared optical frequency comb is a powerful tool for gas *** this study,we demonstrate a simple midinfrared dual-comb spectrometer covering 3±4μm in li Nb O_(3)*** on a low-power fiber laser system,the mid-infrared comb is achieved via intra-pulse difference frequency generation in the li Nb O_(3)*** construct pre-chirp management before supercontinuum generation to control spatiotemporal alignment for pump and signal *** supercontinuum is directly coupled into a chirped periodically poled li Nb O_(3)waveguide for the 3±4μm idler generation.A mid-infrared dual-comb spectrometer based on this approach provides a 100 MHz resolution over25 THz *** evaluate the applicability for spectroscopy,we measure the methane spectrum using the dualcomb *** measured results are consistent with the HITRAN database,in which the root mean square of the residual is 3.2%.This proposed method is expected to develop integrated and robust mid-infrared dual-comb spectrometers on chip for sensing.

关键词： difference frequency generation dual-comb spectroscopy mid-infrared gas sensing nonlinear optics

Low-noise compact fiber laser based on nonlinear polarization evolution in an all-polarization-maintaining figure-8 cavity

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Chinese Optics Letters 2024年第7期22卷 47-52页

作者： lian Zhou Daping Luo Gehui Xie Shiping Xiong Haipeng Lou Zilin Zhao Yuanfeng Di Chenglin Gu wenxue li State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China

We demonstrate an all-polarization-maintaining(APM)fiber mode-locked laser based on nonlinear polarization evolution(NPE).A well-designed Sagnac fiber loop is employed to establish the nonlinear polarization evolution process in a polarization beam splitter(PBS)figure-8 fiber *** loss curves are calculated to verify the saturable absorption characteristic of this NPE-based APM ***,we simulate the pulse propagation process in the cavity to demonstrate the pulse mode-locked ***,we also design a realizable compact scheme to further reduce noise disturbances,achieving a 101-fs mode-locked pulse train with a 0.3-mrad integrated phase noise and a 0.006%integrated relative intensity noise(RIN).This figure-8 fiber laser provides a new scheme for compacting low-noise compact APM fiber lasers based on the NPE mode-locked mechanism.

关键词： ultrafast laser fiber laser polarization-maintaining.

Nutrition strategies to control post-weaning diarrhea of piglets: From the perspective of feeds

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Animal Nutrition 2024年第2期17卷 297-311页

作者： Qingsong Tang Tianyi Lan Chengyu Zhou Jingchun Gao liuting Wu Haiyang Wei wenxue li Zhiru Tang Wenjie Tang Hui Diao Yetong Xu Xie Peng Jiaman Pang Xuan Zhao Zhihong Sun Laboratory for Bio-Feed and Molecular Nutrition College of Animal Science and Technology Southwest University Animal Breeding and Genetics Key Laboratory of Sichuan Province Sichuan Animal Science Academy Yibin Academy of Southwest University

Post-weaning diarrhea(PWD) is a globally significant threat to the swine industry. Historically, antibiotics as well as high doses of zinc oxide and copper sulfate have been commonly used to control ***, the development of bacterial resistance and environmental pollution have created an interest in alternative strategies. In recent years, the research surrounding these alternative strategies and the mechanisms of piglet diarrhea has been continually updated. Mechanically, diarrhea in piglets is a result of an imbalance in intestinal fluid and electrolyte absorption and secretion. In general, enterotoxigenic Escherichia coli(ETEC) and diarrheal viruses are known to cause an imbalance in the absorption and secretion of intestinal fluids and electrolytes in piglets, resulting in diarrhea when Cl secretion-driven fluid secretion surpasses absorptive capacity. From a perspective of feedstuffs, factors that contribute to imbalances in fluid absorption and secretion in the intestines of weaned piglets include high levels of crude protein(CP), stimulation by certain antigenic proteins, high acid-binding capacity(ABC), and contamination with deoxynivalenol(DON) in the diet. In response, efforts to reduce CP levels in diets,select feedstuffs with lower ABC values, and process feedstuffs using physical, chemical, and biological approaches are important strategies for alleviating PWD in piglets. Additionally, the diet supplementation with additives such as vitamins and natural products can also play a role in reducing the diarrhea incidence in weaned piglets. Here, we examine the mechanisms of absorption and secretion of intestinal fluids and electrolytes in piglets, summarize nutritional strategies to control PWD in piglets from the perspective of feeds, and provide new insights towards future research directions.

关键词： Post-weaning diarrhea Fluid secretion Feed Nutritional regulation strategies Piglet

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貂蝉之名渊源考——兼谈中华文化符号的建构

中国社会科学院大学学报 2024年第5期44卷 99-116+159+161页

作者：李文学裴丽丽西南大学历史文化学院

《三国演义》中的美女貂蝉之名源自战国时期赵国发明的貂蝉冠。新石器时代中晚期以后,中原地区的蝉文化和东北地区及蒙古高原地区的貂文化在黄河流域经历了长期融合,貂蝉冠正是这种融合的产物。秦汉时期,统治者将貂蝉冠配授给宫廷侍官... 详细信息

《三国演义》中的美女貂蝉之名源自战国时期赵国发明的貂蝉冠。新石器时代中晚期以后,中原地区的蝉文化和东北地区及蒙古高原地区的貂文化在黄河流域经历了长期融合,貂蝉冠正是这种融合的产物。秦汉时期,统治者将貂蝉冠配授给宫廷侍官。魏晋南北朝时期,女尚书佩戴貂蝉冠使后者开始与女性结合,后赵的改革使貂蝉冠进一步与美女结合。唐宋时期,貂蝉冠的配授对象由皇帝侍官群体转为外朝高官群体,适用范围明显扩大。迄于元代,貂蝉冠的适用范围虽大大缩小,但在客观上促进了貂蝉之名的民间化和大众化。这些历史渊源为美女貂蝉的得名及其故事的产生和传播提供了条件。貂蝉的“成名”是融合创造、继承创新的结果,其过程生动体现了中华文化的连续性、创新性、包容性和多元统一性。

关键词：貂蝉貂蝉冠中华文化文化符号

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1例犬急性肾衰竭的诊断和治疗

现代畜牧兽医 2024年第3期 55-58页

作者：刘玉玲李文学延边大学农学院吉林延吉133002

近年来,动物肾衰竭的发病率逐年升高,常见于幼龄与老龄动物。一体重4 kg的4岁泰迪出现精神变差、食欲减退、呕吐等症状,遂进行临床检查、血常规检查、生化检查以及超声波检查。血常规检查结果显示,患犬体内存在炎症反应;血液生化检查结... 详细信息

近年来,动物肾衰竭的发病率逐年升高,常见于幼龄与老龄动物。一体重4 kg的4岁泰迪出现精神变差、食欲减退、呕吐等症状,遂进行临床检查、血常规检查、生化检查以及超声波检查。血常规检查结果显示,患犬体内存在炎症反应;血液生化检查结果显示,白球比偏低,碱性磷酸酶、尿素氮、肌酐、磷等指标升高,怀疑肾脏出现问题;超声波检查结果确定其患有急性肾衰。经过一段时间药物治疗后,患犬痊愈。文章对该病例的发病症状、检测结果以及治疗方法等进行分析、讨论,以期为兽医临床治疗急性肾衰提供参考。

关键词：犬急性肾衰竭肾衰竭

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牛蒡提取物安全性的初步研究

医学动物防制 2024年第6期40卷 596-601,605页

作者：李晓华聂文强吴宝剑李军涛李文学杨光宇广东药科大学附属第一医院全科医学科广东广州510440 暨南大学药学院广州市疾病预防控制中心毒理学检验部

目的以牛蒡提取物为研究对象,初步对牛蒡的安全性进行毒理学评价。方法根据卫生部《保健食品检验与评价技术规范》(2003年版)要求,选择急性经口毒性试验、鼠伤寒沙门菌回复突变(Salmonella typhimurium/reverse mutation,Ames)试验、小... 详细信息

目的以牛蒡提取物为研究对象,初步对牛蒡的安全性进行毒理学评价。方法根据卫生部《保健食品检验与评价技术规范》(2003年版)要求,选择急性经口毒性试验、鼠伤寒沙门菌回复突变(Salmonella typhimurium/reverse mutation,Ames)试验、小鼠骨髓细胞微核试验、小鼠精子畸形试验和30d灌胃试验对牛蒡提取物进行毒性评价。结果急性经口毒性试验动物灌胃后未见明显中毒反应,牛蒡提取物小鼠急性经口半数致死量(median lethal dose,LD50)>15.0g/kg·bw,毒性分级属无毒级;Ames试验牛蒡提取物回变菌落数未超过溶剂对照的2倍且无剂量-反应关系,提示牛蒡提取物致突变试验结果为阴性;牛蒡提取物各剂量组骨髓细胞微核率和精子畸形率与溶剂对照组比较,差异无统计学意义(χ^(2)=7.035、4.216,P>0.05);牛蒡提取物大鼠30d经口灌胃试验期间,动物生长发育良好,体质量、食物利用率、血液学、血液生化学、脏器系数和组织病理学等相关指标均未见明显特异性毒理学变化,最大未观察到有害作用剂量(no-observed-adverse-effect level,NOAEL)8.0g/kg·bw。结论牛蒡提取物急性毒性分级属无毒级,无遗传毒性,在本研究实验条件和试验剂量下,可初步认定其作为中药材及保健食品是安全的。

关键词：牛蒡提取物保健食品中药材毒性研究安全性评价

超声造影定量分析大鼠肝急性移植物抗宿主病的实验研究

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中华医学超声杂志（电子版） 2024年第1期21卷 75-81页

作者：刘逸群朱家安熊钰辛雨薇曲琳琳杨力李文雪田辉北京大学人民医院超声医学科 100044

目的探讨超声造影技术定量参数在评价肝急性移植物抗宿主病(aGVHD)中的诊断价值。方法健康雌性Wistar大鼠42只,随机选取6只作为对照组,余36只作为移植受体,10只Fischer 344大鼠作为供体,进行骨髓移植,以建立aGVHD模型。术后每周随机抽取... 详细信息

目的探讨超声造影技术定量参数在评价肝急性移植物抗宿主病(aGVHD)中的诊断价值。方法健康雌性Wistar大鼠42只,随机选取6只作为对照组,余36只作为移植受体,10只Fischer 344大鼠作为供体,进行骨髓移植,以建立aGVHD模型。术后每周随机抽取6只大鼠,进行临床观察并评分;进行超声造影检查观察肝实质血流灌注情况并脱机分析时间-强度曲线(TIC),得出峰值强度(PI)、达峰时间(TTP)、平均渡越时间(MTT)超声造影定量指标。检查结束后处死大鼠取肝标本进行病理诊断并评分。采用H检验比较对照组、未发生aGVHD组(nGVHD组)及aGVHD组间临床评分、超声造影各参数的差异,分析aGVHD组不同病程[依据病理严重程度分为:轻度组(病理2级)、中度组(病理3级)和重度组(病理4级)]超声造影定量参数的变化情况。采用Spearman检验分析临床评分、TIC参数与病理评分的相关性。将临床评分、超声造影定量参数纳入二元Logistic回归分析得出整体预测参数,绘制受试者操作特征(ROC)曲线,并采用Delong检验与临床评分和超声造影参数对肝aGVHD的诊断效能进行比较。结果aGVHD组大鼠(24只)的PI降低、TTP及MTT增高,与对照组和nGVHD组相比差异均具有统计学意义(P均<0.05)。重度组MTT高于轻度组[(135.21±27.71)s vs(84.37±25.26)s],差异具有统计学意义(P=0.020)。PI、MTT与病理评分有高度相关性(r=-0.790、0.733,P均<0.001),TTP与病理学评分呈中度相关性(r=0.489,P=0.001)。临床评分、超声造影参数、整体参数诊断aGVHD的ROC曲线下面积(AUC)分别为0.698、0.885、0.910,根据ROC曲线分析,其敏感度分别为79.2%、87.5%、91.7%,特异度分别为75.0%、83.3%、83.3%。超声造影参数和整体预测参数的诊断效能高于临床评分(Z=2.290,P=0.022;Z=2.412,P=0.016)。结论超声造影定量参数为肝aGVHD的诊断提供形态学依据,有望成为评估肝aGVHD影像学新方法。

关键词：肝移植物抗宿主病超声造影动物模型

Grain-scale deformation in a Mg-0.8wt% Y alloy using crystal plasticity finite element method

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Journal of Materials Science & Technology 2019年第10期35卷 2200-2206页

作者： wenxue li Leyun Wang Bijin Zhou Chuanlai liu Xiaoqin Zeng National Engineering Research Center of light Alloy Net Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China The State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai200240China

Magnesium(Mg) alloys with hexagonal close-packed(HCP) structure usually have a poor ductility at room temperature. The addition of yttrium(Y) can improve the ductility of Mg alloys. To understand the underlying mechanism, crystal plasticity finite element method(CPFEM) was employed to simulate the tensile deformation of a Mg-0.8 wt% Y alloy. The simulated stress–strain curve and the grain-scale slip activities were compared with an in-situ tensile test conducted in a scanning electron *** to the CPFEM result, basal slip is the dominant deformation mode in the plastic deformation stage, accounting for about 50% of total strain. Prismatic slip and pyramidal a slip are responsible for about 25% and 20% of the total strain, respectively. Pyramidal c + a slip and twinning, on the other hand,accommodate much less strain.

关键词： Magnesium alloys Crystal Plasticity finite element modeling EBSD Dislocation Mechanical Behavior

Role of trichome of Pteris vittata *** arsenic hyperaccu-mulation

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Science China(life Sciences) 2005年第2期48卷 148-154页

作者： li wenxue CHEN Tongbin CHEN Yang LEI Mei Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Environmental scanning electron microscope(ESEM)fitted with an energy disper-sive X-ray microanalyzer(EDX)was used to investigate the surface micromorphology and arse-nic(As)micro-distribution in Chinese brake(Pteris vittata L.).It was found that amounts of trichome,which possessed multicellular structure with the average length of 160μm and with an average diameter of 28μm,existed in the frond of ***,and the density of trichome on the pinnate axial surface was higher than that on the *** X-ray peak of As was recorded in the epidermal cell and *** relative weight of As in the pinnate trichome,which con-tained the highest concentration of As among all tissues of the plant,was 2.4 and 3.9 times as much as that in the epidermal and mesophyllous cells,*** As concentrations in the basal and stalk cells of the same trichome were higher than that in its cap *** is the first time to report that the trichome of *** plays an important role in arsenic *** finding from the present study implies that much attention should be paid to the role of the trichome in understanding the hyperaccumulation and detoxicity of As in the hyperaccumulator and improving the ability of As accumulation.

关键词： arsenic environmental scanning electron microscope(ESEM) hyperaccumulation micro-distribution Pteris vittata L. trichome.

Morphological structures of poly(vinylidene fluoride)/montmorillonite nanocomposites

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Science China Chemistry 2007年第6期50卷 790-796页

作者： SONG YuMing ZHAO ZhuDi YU wenxue li Bo CHEN XinFang College of Materials Science and Engineering Jilin University Changchun 130012 China College of Materials Science and Engineering Jilin University Changchun 130012 China College of Materials Science and Engineering Jilin University Changchun 130012 China College of Materials Science and Engineering Jilin University Changchun 130012 China College of Materials Science and Engineering Jilin University Changchun 130012 China

Poly(vinylidene fluoride)(PVDF)/montmorillonite(MMT)nanocomposites were prepared by melt blending a kind of organically modified montmorillonite with *** morphological structures of the nanocomposites were studied using X-ray diffraction(XRD),transmission electron microscopy(TEM),Fourier transform infrared(FTIR)spectroscopy,and differential scanning calorimetry(DSC).The results indicate that organically modified montmorillonites are in the form of intercalation,exfoliation,and fragments in the PVDF *** the composites,the(001)peak position of MMT was found to shift to a lower angle in XRD patterns,and some MMT fragments could be observed under *** loading was favorable to producing the piezoelectric beta phase in the PVDF matrix and caused internal stress in a *** the same time,the crystallinity and spherulite size of PVDF decreased with the MMT *** induced beta phase is stable even at high temperatures(160℃).For these changes in morphological structures,some possible explanations were proposed based on the experimental results.

关键词： organically modified montmorillonite, nanocomposite, crystalline structure