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Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 773-789页

作者： Hua-Zhen Jiang Zheng-Yang Li Tao Feng Peng-yue wu Qi-Sheng Chen Shao-Ke yao Jing-yu Hou School of Engineering Science University of Chinese Academy of SciencesBeijing100190China Institute of Mechanics Chinese Academy of SciencesBeijing100190China Beijing E-Plus-3D Technology Co. LTDBeijing102299China

In the present work,316 L stainless steel specimens are fabricated by selective laser melting(SLM)via optimized laser process *** effects of two extrinsic factors,i.e.,strain rate and annealing temperature,on the mechanical performance of SLM-processed parts are *** two intrinsic factors,namely strain rate sensitivity m and work hardening exponent n,which control the tensile properties of the as-built samples,are *** structure characterizations show that cellular structure and crystalline grain exhibit apparently different thermal stability at 873 *** testing reveals that the yield strength decreases from 584±16 MPa to 323±2 MPa,while the elongation to failure increases from(46±1)%to(65±2)%when annealing temperature varies from 298 K to 1328 *** n value increases from 0.13 to 0.33 with the increase in annealing *** to the presence of fine cellular structures and high relative density achieved in as-printed 316 L samples,a strong dependence between tensile yield strength and strain rate is *** addition,the strain rate sensitivity of the SLM-produced 316 L part(m=0.017)is much larger than that of conventional coarse-grained part(m=0.006),whereas the n value increases slightly from 0.097 to 0.14 with increasing strain rate.

关键词： Selective laser melting 316L stainless steel Heat treatment Strain hardening behaviors Mechanical property

三明市妊娠期甲状腺激素参考范围的建立及分析

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中山大学学报（医学科学版） 2024年第3期45卷 429-437页

作者：林穗雯姚敏蓉吴芳燕赵勇林金梅刘斌中山大学附属第一医院妇产科广东广州510080 广东省妇产疾病临床医学研究中心广东广州510080 三明市第一医院产科福建三明365099 三明市沙县区总医院妇产科福建三明365500

【目的】建立福建省三明地区妊娠期特异性甲状腺激素参考范围,研究各指标在妊娠期的变化趋势并与国内其他地区水平进行比较。【方法】收集2023年3月29日至2023年6月28日在三明市第一医院产科就诊且符合研究纳入标准的605名单胎妊娠孕妇... 详细信息

【目的】建立福建省三明地区妊娠期特异性甲状腺激素参考范围,研究各指标在妊娠期的变化趋势并与国内其他地区水平进行比较。【方法】收集2023年3月29日至2023年6月28日在三明市第一医院产科就诊且符合研究纳入标准的605名单胎妊娠孕妇的临床资料,并纳入同期229名非妊娠妇女作为对照组。检测研究对象的促甲状腺激素(TSH)、游离甲状腺素(FT_(4))及游离三碘甲状腺原氨酸(FT_(3))水平。建立妊娠早、中、晚期甲状腺激素参考范围,以P2.5~P97.5区间表示,对比各指标在妊娠期的变化趋势,并与全国各地区相同类型研究结果进行比较。【结果】TSH、FT_(4)、FT_(3)在妊娠各期的总体差异具有统计学意义(P均<0.05)。与非妊娠妇女相比,妊娠早期TSH、FT_(4)水平明显降低,妊娠早期FT_(3)水平与非孕期妇女相似。妊娠中期开始,TSH水平升高、FT_(3)及FT_(4)水平逐渐下降。本研究建立的妊娠期甲状腺相关指标参考范围如下:妊娠早期:TSH(0.068,2.943)μU/mL,FT_(3)(4.302,6.888)pmol/L,FT_(4)(8.240,14.719)pmol/L;妊娠中期:TSH(0.419,3.274)μU/mL,FT_(3)(4.074,6.629)pmol/L,FT_(4)(6.726,11.980)pmol/L;妊娠晚期:TSH(0.422,3.570)μU/mL,FT_(3)(3.741,5.850)pmol/L,FT_(4)(6.103,10.347)pmol/L。全国各省市建立的妊娠期甲状腺激素参考范围具有较大差异。【结论】妊娠妇女甲状腺功能与非妊娠妇女不同,且妊娠各期孕妇TSH、FT_(3)、FT_(4)水平存在显著差异。妊娠期甲状腺激素受到地域、人群、实验室检测方法等多因素的影响。因此,建立三明地区特异性的妊娠期甲状腺激素参考范围有益于本地区妊娠人群甲状腺疾病的诊治。

关键词：妊娠甲状腺激素参考范围甲状腺疾病妊娠结局各省市比较

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宽带滤波器传输线法去嵌的研究

电子元件与材料 2024年第7期43卷 866-871页

作者：周艺蒙帅垚胡月吴传贵张万里重庆邮电大学光电工程学院重庆400065 电子科技大学电子薄膜与集成器件国家重点实验室四川成都610054 电子科技大学重庆微电子产业技术研究院重庆401332

为准确获取谐振器材料参数,采用开路短路法、集总参数法、传输线法三种方法分别对谐振器进行去嵌,并分析去嵌对滤波器产生的影响。其中传输线法去嵌无需流片,仿真即可得出谐振器测试结构的寄生参数。采用传输线法对串联、并联谐振去嵌,... 详细信息

为准确获取谐振器材料参数,采用开路短路法、集总参数法、传输线法三种方法分别对谐振器进行去嵌,并分析去嵌对滤波器产生的影响。其中传输线法去嵌无需流片,仿真即可得出谐振器测试结构的寄生参数。采用传输线法对串联、并联谐振去嵌,并运用去嵌后的谐振器材料参数搭建滤波器,滤波器采用九阶π型电路拓扑结构,其带宽为160 MHz,阻带抑制为-25 dB。证实谐振器的测试结构对宽带声表面波滤波器带宽、阻带和零点造成影响,使得去嵌后的滤波器左侧零点向低频偏移,低频抑制上升,高频抑制下降,通带插入损耗增加。

关键词：去嵌开路短路法集总参数法传输线法宽带滤波器 π型电路拓扑结构

The chemical structures, biosynthesis, and biological activities of secondary metabolites from the culinary-medicinal mushrooms of the genus Hericium: a review

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Chinese Journal of Natural Medicines 2024年第08期 676-698页

作者： QI Jianzhao wu Jing KANG Shijie GAO Jingming Hirokazu Kawagishi LIU Hongwei LIU Chengwei Key Laboratory for Enzyme and Enzyme-Like Material Engineering of Heilongjiang College of Life Science Northeast Forestry University Shaanxi Key Laboratory of Natural Products & Chemical Biology College of Chemistry & Pharmacy Northwest A&F University Faculty of Agriculture Shizuoka University State Key Laboratory of Mycology Institute of Microbiology Chinese Academy of Sciences

Fungal phytochemicals derived from higher fungi, particularly those from the culinary-medicinal genus Hericium, have gained significant attention in drug discovery and healthcare. This review aims to provide a comprehensive analysis of the chemical structures, biosynthetic pathways, biological activities, and pharmacological properties of monomeric compounds isolated from Hericium species. Over the past 34 years, 253 metabolites have been identified from various Hericium species, including cyathane diterpenes,alkaloids, benzofurans, chromenes, phenols, pyrones, steroids, and other miscellaneous compounds. Detailed investigations into the biosynthesis of erinacines, a type of cyathane diterpene, have led to the discovery of novel cyathane diterpenes. Extensive research has highlighted the biological activities and pharmacological properties of Hericium-derived compounds, with particular emphasis on their neuroprotective and neurotrophic effects, immunomodulatory capabilities, anti-cancer activity, antioxidant properties, and antimicrobial actions. Erinacine A, in particular, has been extensively studied. Genomic, transcriptomic, and proteomic analyses of Hericium species have facilitated the discovery of new compounds and provided insights into enzymatic reactions through genome mining. The diverse chemical structures and biological activities of Hericium compounds underpin their potential applications in medicine and as dietary supplements. This review not only advances our understanding of Hericium compounds but also encourages further research into Hericium species within the realms of medicine, health, functional foods, and agricultural microbiology. The broad spectrum of compound types and their diverse biological activities present promising opportunities for the development of new pharmaceuticals and edible products.

关键词：

Dilation,discrimination and Uhlmann's theorem of link products of quantum channels

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Chinese Physics B 2024年第3期33卷 201-206页

作者：雷强操刘桁 Asutosh Kumar 武俊德 School of Mathematical Sciences Harbin Institute of TechnologyHarbin 150001China Department of Physics Gaya CollegeMagadh UniversityRampurGaya 823001India School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China

We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n *** also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels.

关键词： quantum channels link products Stinespring dilation theorem Uhlmann's theorem

种植支抗对骨性Ⅱ类高角患者垂直向控制作用的回顾分析

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中华口腔正畸学杂志 2024年第1期31卷 11-17页

作者：梁炜吴伟强赵宁宁汤瑶韩冰林久祥北京大学口腔医学院·口腔医院正畸科、国家口腔医学中心、国家口腔疾病临床医学研究中心、口腔生物材料和数字诊疗装备国家工程研究中心北京100081 北京大学口腔医学院·口腔医院第五门诊部、国家口腔医学中心、国家口腔疾病临床医学研究中心、口腔生物材料和数字诊疗装备国家工程研究中心北京100050

目的探讨联合使用上前牙区及上磨牙区微种植体支抗对骨性Ⅱ类高角拔牙病例的垂直向控制中的作用。方法通过回顾性研究,采用自身对照的方法,选取10例联合使用了上前牙区和上磨牙区微种植体支抗的骨性Ⅱ类高角拔牙矫正的患者,对其治疗前... 详细信息

目的探讨联合使用上前牙区及上磨牙区微种植体支抗对骨性Ⅱ类高角拔牙病例的垂直向控制中的作用。方法通过回顾性研究,采用自身对照的方法,选取10例联合使用了上前牙区和上磨牙区微种植体支抗的骨性Ⅱ类高角拔牙矫正的患者,对其治疗前后的头颅侧位片进行头影测量和比较分析。结果患者平均疗程31.6个月,矫治后下颌平面角SN-MP减小1.62°±0.79°(P<0.001),FMA减小2.25°±0.99°(P<0.001),后/前下面高比增加0.54%±1.18%(P<0.001),Y轴角减小1.55°±1.77°(P<0.001),ANB角减小0.78°±0.84°(P=0.017);面角增大2.52°±1.60°(P=0.001),Z角增大8.15°±3.33°(P<0.001);上颌第一磨牙到腭平面的距离减少(0.39±0.28)mm(P=0.002);上切牙到腭平面的距离减小(2.46±0.41)mm(P<0.001);平面与眶耳平面的夹角减小1.16°±1.46°(P=0.033),差异均具有统计学意义。结果显示矫正后上前牙压低、上磨牙压低,而下颌平面和咬合平面均发生了一定的逆时针旋转,从而在一定程度上改善了软组织侧貌。结论在上颌前牙及上磨牙区联合使用微种植体支抗,进行垂直向控制,可以产生一定量的下颌平面逆时针旋转,较好地改善了骨性Ⅱ类高角患者的侧貌。

关键词：高角病例垂直向控制微种植体支抗

NUMERICAL INVESTIGATION OF THE VENTILATED CAVITATING FLOW AROUND AN UNDER-WATER VEHICLE BASED ON A THREE-COMPONENT CAVITATION MODEL

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Journal of Hydrodynamics 2010年第6期22卷 753-759页

作者： JI Bin LUO Xian-wu PENG Xiao-xing ZHANG yao wu yu-lin XU Hong-yuan State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China China Ship Scientific Research Center Wuxi 214082 China State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

Based on the Reynolds-Averaged Navier-Stokes equations and mass transfer model, an approach, where a three-component cavitation model is proposed, is presented to simulate ventilated cavitating flow as well as natural cavitation. In the proposed cavitation model, the initial content of nucleus in the local flow field is updated instantaneously, and is coupled with the Rayleigh-Plesset equation to capture the cavity development. The proposed model is applied to simulate the cavitating flow around an under-water vehicle in different cavitation conditions. The results indicate that for the natural and ventilated cavitation simulation, the predicted cavitation characteristics including the cavity length, cavity diameter and cavity shape agree satisfactorily with the analytic and experimental results, for the ventilated cavitation, the proposed methods reproduce the special behavior that the axial line of the cavity bends and rises at the tail part. The study concludes that the ventilated flow rate of the non-condensate gas influences the development of natural cavitation as well as ventilated cavitation, and the vapor cavity is suppressed remarkably by the gas cavity with the increase of the gas ventilation.

关键词： under-water vehicle natural cavitation ventilated cavitation three-component model

西北印度洋卡尔斯伯格脊卧蚕热液羽流影响区古菌群落动态变化特征

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微生物学报 2024年第6期64卷 1848-1863页

作者：巫苑桢韩喜球谢倩魏铭聪余娟上海交通大学海洋学院上海200240 自然资源部第二海洋研究所自然资源部海底科学重点实验室浙江杭州310012 浙江大学海洋学院浙江舟山316021

【目的】热液羽流在浮力上升和非浮力侧向迁移过程中与背景海水不断进行物质和能量的交换。因海底热液活动和洋流的流速流向均存在动态变化性,热液羽流的高度、物理化学参数和微生物群落也随时空发生演化。然而,由于缺乏热液羽流的长期... 详细信息

【目的】热液羽流在浮力上升和非浮力侧向迁移过程中与背景海水不断进行物质和能量的交换。因海底热液活动和洋流的流速流向均存在动态变化性,热液羽流的高度、物理化学参数和微生物群落也随时空发生演化。然而,由于缺乏热液羽流的长期监测和时序取样,微生物群落(尤其是古菌)的多样性及其时空演化尚不清楚。【方法】2018年7月−2019年6月,在卧蚕1号热液喷口东南300 m处放置了一套带有2个沉积物捕获器(分别距海底300 m和40 m)和一个浊度仪(距海底150 m)的锚系潜标,对热液羽流和热液羽流下方颗粒物沉降区的近底水样进行了为期18个月的观测和时序采样。本研究采用16S rRNA基因高通量测序技术研究了水样中古菌群落的多样性,以了解羽流层和近底沉降层古菌群落结构的特征与时空演化。【结果】热原体纲(Thermoplasmata)、甲烷八叠球菌纲(Methanosarcinia)和甲烷杆菌纲(Methanobacteria)等热液来源古菌,当浊度异常值较高时,它们的丰度也增加。从空间上看,热液羽流区和近底沉降区古菌群落结构在门和纲水平上具有相似性,但在目水平上表现出差异性,而且各主要类群的相对丰度也存在差异,其中热原体纲在羽流层中的丰度普遍高于近底沉降层,而氨氧化古菌和甲烷八叠球菌纲在沉降层的丰度较高。【结论】卧蚕热液区东南300 m热液羽流层和近底沉降层均受到了热液的影响,羽流层受热液影响的程度相对更显著,而近底沉降层除了受到一定程度的热液影响外,还可能受到了再悬浮沉积物的影响。热液贡献大小的动态变化和底层沉积物再悬浮可能是造成热液区近端水体古菌群落时空异质性的主要因素。本研究深化了对热液影响区古生菌群落结构及其月际尺度时空分布特征的认识。

关键词：卧蚕1号热液区热液羽流古菌时空演化印度洋

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巨气管支气管症临床特点分析

心肺血管病杂志 2024年第5期43卷 464-468页

作者：吴艳军林芳于刚刚徐波姚志刚首都医科大学附属北京友谊医院慢性阻塞性肺疾病及呼吸介入治疗 100050

目的:分析巨气管支气管症(tracheobronchomegaly,TBM)患者临床特点,以期提高临床医师对该疾病诊疗认识。方法:回顾性收集首都医科大学附属北京友谊医院呼吸内科近5年诊断巨气管支气管症患者临床资料,分析其基本情况、临床症状及体征、... 详细信息

目的:分析巨气管支气管症(tracheobronchomegaly,TBM)患者临床特点,以期提高临床医师对该疾病诊疗认识。方法:回顾性收集首都医科大学附属北京友谊医院呼吸内科近5年诊断巨气管支气管症患者临床资料,分析其基本情况、临床症状及体征、影像等临床资料。结果:共收集4例患者,临床症状主要为咳嗽、咳痰及喘憋。男女各2例,最小年龄65岁,最大90岁,女性患者无吸烟史,2例男性患者均有吸烟,均有不同程度的气管扩张,2例患者合并耐药的铜绿假单胞菌感染,1例患者合并结核感染,气管插管1例,死亡1例。结论:巨气管支气管症常合并支气管扩张,可合并耐药菌感染,对症治疗尤其是控制感染尤为重要,高龄患者预后差,气道管理复杂,应予以重视。

关键词：巨气管莫-昆综合征支气管扩张

Unveiling blood pressure-associated genes in aortic cells through integrative analysis of GWAS and RNA modification-associated variants

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Chronic Diseases and Translational Medicine 2024年第2期10卷 118-129页

作者： Huan Zhang yuxi Chen Peng Xu Dan Liu Naqiong wu Laiyuan Wang Xingbo Mo Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases Department of EpidemiologySchool of Public HealthMedical College of Soochow UniversitySuzhouJiangsuChina Cardiometabolic Center Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Key Laboratory of Cardiovascular Epidemiology&Department of Epidemiology State Key Laboratory of Cardiovascular DiseaseFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina MOE Key Laboratory of Geriatric Diseases and Immunology School of Public HealthCenter for Genetic Epidemiology and GenomicsMedical College of Soochow UniversitySuzhouJiangsuChina

Background Genome-wide association studies(GWAS)have identified more than a thousand loci for blood pressure(BP).Functional genes in these loci are cell-type *** aim of this study was to elucidate potentially functional genes associated with BP in the aorta through the utilization of RNA modification-associated single-nucleotide polymorphisms(RNAm-SNPs).Methods Utilizing large-scale genetic data of 757,601 individuals from the UK Biobank and International Consortium of Blood Pressure consortium,we identified associations between RNAm-SNPs and *** association between RNAm-SNPs,gene expression,and BP were *** A total of 355 RNAm-SNPs related to m6A,m1A,m5C,m7G,and A-to-I modification were associated with *** related genes were enriched in the pancreatic secretion pathway and renin secretion *** BP GWAS signals were significantly enriched with m6A-SNPs,highlighting the potential functional relevance of m6A in physiological processes influencing ***,m6A-SNPs in CYP11B1,PDE3B,HDAC7,ACE,SLC4A7,PDE1A,FRK,MTHFR,NPPA,CACNA1D,and HDAC9 were *** methylation and differential expression of the BP genes in FTO-overexpression and METTL14-knockdown vascular smooth muscle cells were ***-SNPs were associated with ascending and descending aorta diameter and the genes showed differential methylation between aortic dissection(AD)cases and *** scRNA-seq study,we identified ARID5A,HLA-DPB1,HLA-DRA,IRF1,LINC01091,MCL1,MLF1,MLXIPL,NAA16,NADK,RERG,SRM,and USP53 as differential expression genes for AD in aortic *** The present study identified RNAm-SNPs in BP loci and elucidated the associations between the RNAm-SNPs,gene expression,and *** identified BP-associated genes in aortic cells were associated with AD.

关键词： aortic dissection blood pressure genome-wide association study RNA modification single-cell