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Decline in tree-ring growth of Picea mongolica and its intra-annual eco-physiological responses to drought and cO_(2) enrichment in semi-arid china

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Journal of Forestry Research 2024年第4期35卷 89-101页

作者： Xiaomin Zeng Ping Ni Xiaohong Liu wenzhi Wang Yao Li Wenchao Wang School of Geography and Tourism Shaanxi Normal UniversityXi’an 710119People’s Republic of China The Key Laboratory of Mountain environment Evolution and Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041People’s Republic of China cAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China University of chinese Academy of Sc.ences Beijing 100049People’s Republic of China

Episodes of drought-induced decline in tree growth and mortality are becoming more frequent as a result of climate warming and enhanced water stress in semi-arid ***,the ecophysiological mechanisms under-lying the impact of drought on tree growth remains *** this study,earlywood and latewood tree-ring growth,δ^(13)c,andδ^(18)O chronologies of Picea mongolica from 1900 to 2013 were developed to clarify the intra-and inter-annual tree-ring growth responses to increasingly fre-quent *** results indicate that annual basal area increment residuals(BAI_(res)),which removed tree age and size effects,have significantly decreased since ***-ever,the decreasing trend of earlywood BAI_(res) was higher than that of *** response analysis suggests that the dominant parameters for earlywood and latewood proxies(BAI_(res),δ^(13)c andδ^(18)O)were drought-related climate variables(Palmer drought severity index,temperature,rela-tive humidity,and vapor pressure deficit).The most signifi-cant period of earlywood and latewood proxies’responses to climate variables were focused on June-July and July-August,***_(res),andδ^(13)c were significantly affected by temperature and moisture conditions,whereasδ^(18)O was slightly *** stomatal conduct-ance due to drought outweighed the influence of increasing cO_(2) on intrinsic water use effic.ency(iWUE),and ultimately led to a decline in BAI_(res).compared to latewood,the faster decreasing BAI_(res) and smaller increasing iWUE of early-wood suggested trees were more vulnerable to water stress in the early growing *** study provides insights into the inter-and intra-annual mechanisms of tree-ring growth in semi-arid regions under rising cO_(2) and climate change.

关键词： Tree growth Drought Water-use effic.ency Seasonal differences Stable isotopes

Influence of sex on outcomes of liver transplantation for hepatocellular carcinoma:a multicenter cohort study in china

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cancer Biology & Medicine 2024年第4期21卷 347-362页

作者： Jian c.en Zhe Yang Fengqiang Gao Zhisheng Zhou Junli c.en Di Lu Kai Wang Meihua Sui Zhengxin Wang wenzhi Guo Guoyue Lyu Haizhi Qi Jinzhen cai Jiayin Yang Shusen Zheng Xiao Xu Zhejiang University School of Medicine Hangzhou 310030China Institute of Organ Transplantation Zhejiang UniversityHangzhou 310030China Department of Hepatobiliary and Pancreatic Surgery Shulan Hospital of HangzhouHangzhou 310006China National center for Healthcare Quality Management in Liver Transplant Hangzhou 310003China Department of General Surgery Huashan HospitalFudan UniversityShanghai 200040China Department of Hepatobiliary and Pancreatic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Department of Hepatobiliary and Pancreatic Surgery The First Hospital of Jilin UniversityChangchun 130021China Department of Liver Transplantation Second Xiangya HospitalCentral South UniversityChangsha 410008China Department of Organ Transplantation center The Affiliated Hospital of Qingdao UniversityQingdao 266003China Department of Liver Surgery and Liver Transplantation center West China HospitalSichuan UniversityChengdu 610044China NHc Key Laboratory of combined Multi-organ Transplantation Hangzhou 310003China Department of Hepatobiliary and Pancreatic Surgery The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Objective:Sex-specific differences are observed in various liver diseases,but the influence of sex on the outcomes of hepatocellular carcinoma(Hcc)after liver transplantation(LT)remains to be *** study is the first chinese nationwide investigation of the role of sex in post-LT outcomes in patients with ***:Data for recipients with Hcc registered in the china Liver Transplant Registry between January 2015 and December 2020 were *** associations between donor,recipient,or donor-recipient transplant patterns by sex and the post-LT outcomes were studied with propensity score matching(PSM).The survival associated with different sex-based donor-recipient transplant patterns was further ***:Among 3,769 patients enrolled in this study,the 1-,3-,and 5-year overall survival(OS)rates of patients with Hcc after LT were 96.1%,86.4%,and 78.5%,respectively,in female recipients,and 95.8%,79.0%,and 70.7%,respectively,in male recipients after PSM(P=0.009).However,the OS was comparable between recipients with female donors and male *** analysis indicated that male recipient sex was a risk factor for post-LT survival(HR=1.381,P=0.046).Among the donor-recipient transplant patterns,the male-male donor-recipient transplant pattern was associated with the poorest post-LT survival(Pconclusions:Our findings highlighted that the post-LT outcomes of female recipients were significantly superior to those of male recipients,and the male-male donor-recipient transplant pattern was associated with the poorest post-LT *** from male donors may provide the most benefit to female *** results indicate that sex should be considered as a critical factor in organ allocation.

关键词： Sex liver transplantation hepatocellular carcinoma outcome recipient donor

Topological phase transition in compressed van der Waals superlattice heterostructure BiTecl/HfTe_(2)

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chinese Physics B 2024年第8期33卷 437-442页

作者：李志磊李殷翔王奕婷陈文执陈斌 Tin Ka-Ping college of Sc.ence University of Shanghai for Science and TechnologyShanghai 200093China

Based on first-principles calculations,we investigate the electronic band structures and topological properties of heterostructure BiTecl/HfTe_(2) under c-direction *** the primitive structure,this material undergoes a phase transition from an insulator with a narrow indirect gap to a metal by strong spin-orbital *** strain effect is considered,band inversion at time-reversal invariant point Z is responsible for the topological phase *** nontrivial topologies are caused by two different types of band *** observable topological surface states in(110)surface also support that this material experiences topological phase transition *** layered heterostructure with van der Waals force provides us with a new desirable platform upon which to control topological phase transition and construct topological superconductors.

关键词： topological phase transition surface states strain effect heterostructure

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血浆基质在牙髓根尖周病治疗中的应用

口腔疾病防治 2024年第2期32卷 81-88页

作者：杨雪超李文芝广州医科大学附属口腔医院牙体牙髓科·广东省口腔组织修复与重建工程技术中心·广州市口腔再生医学基础与应用研究重点实验室广东广州510182

血浆基质作为一种自体血液离心产物,具有再生修复的功能,已被广泛应用于口腔颌面部软硬组织再生修复、皮肤美容等领域,并取得了较好的效果。目前,牙髓再生治疗和根尖手术已成为保存牙髓以及保存患牙的主要方法,生物活性材料的应用至关重... 详细信息

血浆基质作为一种自体血液离心产物,具有再生修复的功能,已被广泛应用于口腔颌面部软硬组织再生修复、皮肤美容等领域,并取得了较好的效果。目前,牙髓再生治疗和根尖手术已成为保存牙髓以及保存患牙的主要方法,生物活性材料的应用至关重要,血浆基质作为一种自体生物活性材料,较易获取,可塑性强,具有天然优势。血浆基质可应用于以下情况:①无法刺激根尖出血的根尖孔未闭合年轻恒牙的牙髓血运重建术;②存在骨缺损的根尖屏障术及大面积穿孔髓室底或根侧壁修补术;③大面积根尖病变,伴或不伴随牙周疾病患牙的根尖手术。因血浆基质为自身血液来源制品,使用方面无明显禁忌。虽然已有系统综述表明,相比传统血凝块,血浆基质作为天然再生支架,可有效促进牙髓根尖周病的再生性修复。然而,由于血浆基质的特性受不同制备方式的影响,其适用范围有所差异。此外,目前尚缺乏血浆基质长期的临床研究结果,且组织学证据较难获取,仍然需要大量的体内外研究进一步探索。本文将对不同血浆基质在牙髓再生、根尖手术中的骨组织再生等方面的应用进行阐述,以期为临床医生在适应证选择及预后评估时提供参考。

关键词：血浆基质牙髓血运重建术牙髓再生修复根尖手术牙体硬组织修复根尖诱导成形髓室底穿孔修补富血小板血浆富血小板纤维蛋白浓缩生长因子

激光冲击诱导应力波对残余应力孔洞形成的影响

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表面技术 2024年第19期53卷 153-163页

作者：盛湘飞谭慧勇袁文志苟江龙李智南华大学机械工程学院湖南衡阳421001 南华大学土木工程学院湖南衡阳421001

目的揭示残余应力孔洞形成的影响机制。方法采用有限元动力学仿真,实现对激光冲击诱导应力波传播过程的捕捉和特性分析。结果在2000 ns以内的光斑作用区域,材料的初始应力仅受到激光冲击诱导Ⅱ类应力波的扰动作用,此扰动作用由光斑中心... 详细信息

目的揭示残余应力孔洞形成的影响机制。方法采用有限元动力学仿真,实现对激光冲击诱导应力波传播过程的捕捉和特性分析。结果在2000 ns以内的光斑作用区域,材料的初始应力仅受到激光冲击诱导Ⅱ类应力波的扰动作用,此扰动作用由光斑中心向外依次减弱,引起的应力波动幅值由2459 MPa降至224 MPa;在其他工艺参数相同的情况下,残余应力孔洞随着峰值压力和脉宽的增加而变得更加明显,应力幅值差σ_(k)分别由0、114 MPa增至454、568 MPa,孔洞直径d_(k)分别由0、0.8 mm增至约1.4 mm,光斑直径的影响相对较弱。在激光能量3 J的作用下,空间高斯分布对应结果存在应力孔洞,σ_(k)、d_(k)分别为190 MPa、1 mm。将空间平顶分布激光能量增至7 J,对应结果由3 J激光能量时的无应力孔洞转变为存在明显应力孔洞,σ_(k)、d_(k)分别为634 MPa、1.4 mm。另外,在激光能量3 J的作用下,材料1的应力孔洞最显著,σ_(k)、d_(k)分别为207 MPa、1.4 mm,均高于材料2和材料3的对应值。凸圆面、平面和凹圆面对应的σ_(k)分别为212、190、83 MPa,d_(k)均为1 mm。结论在圆形光斑激光冲击载荷作用下,加载和卸载过程中形成的应力波在光斑中心的汇聚作用均较强,导致光斑中心区域材料持续出现正反向屈服,进而形成残余应力孔洞;在相同参数条件下,激光能量越高,则材料的力学性能越低,应力波扰动作用越强,应力孔洞现象越明显。

关键词：激光冲击应力波残余应力应力孔洞有限元分析镍基高温合金

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The ecological role of dew in assisting seed germination of the annual desert plant species in a desert environment, northwestern china

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Journal of Arid Land 2016年第2期8卷 264-271页

作者： ZHUANG Yanli ZHAO wenzhi Linze Inland River Basin Research Station Chinese Ecosystem Research Network Key Laboratory of Ecohydrology of Inland River Basin Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

It is important to understand the effects of dew events on non-mucilaginous seed germination of annual desert plant species during dry seasons, which is critical to maintaining long-term soil seed banks in a harsh desert environment. We hypothesize that dew deposition also assists in the non-mucilaginous seed germination of annual desert species. A common field dew treatment experiment was conducted in the Linze Inland River Basin Research Station to investigate the effects of dew deposition on the seed germination of four annual species, including Agriophyllum squarrosum, corispermum mongoficum, Bassia dasyphylla and Halogeton arachnoideus. The results showed that the presence of dew significantly increased seed germination percentages and decreased the nonviable seed percentages of B. dasyphylla and H. arachnoideus, whereas there was no such trend for the seeds of c. mongolicum and A. squarrosum. The ecological effects of dew on the seed germination and viability of the annual desert plants were species specific. Although dew wetting is insuffic.ent to cause seed germination, it may help in priming the seeds.

关键词： dew deposition seeds hydration and dehydration seeds viability

HPLc同时测定小儿氨酚黄那敏制剂中的4种甜味剂

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华西药学杂志 2024年第3期39卷 333-336页

作者：阿玉梅魏文芝陈学艳彭双青海省药品检验检测院国家药品监督管理局中药(藏药)质量控制重点实验室青海省中藏药现代化研究重点实验室青海西宁810016

目的采用HPLc法同时测定制剂中4种甜味剂(安赛蜜、糖精钠、阿司帕坦、甜菊苷)的含量。方法采用Agilent Zorbax SB-c_(18)色谱柱(250 mm×4.6 mm,5μm),流动相A为0.02 mol·L^(-1)磷酸二氢铵溶液(pH4.4),B为乙腈,梯度洗脱,流速1.0 mL·mi... 详细信息

目的采用HPLc法同时测定制剂中4种甜味剂(安赛蜜、糖精钠、阿司帕坦、甜菊苷)的含量。方法采用Agilent Zorbax SB-c_(18)色谱柱(250 mm×4.6 mm,5μm),流动相A为0.02 mol·L^(-1)磷酸二氢铵溶液(pH4.4),B为乙腈,梯度洗脱,流速1.0 mL·min^(-1),检测波长200 nm(糖精钠、阿司帕坦、甜菊苷)、226 nm(安赛蜜),柱温30℃,进样量10μL。结果安赛蜜、糖精钠、阿司帕坦、甜菊苷均达到基线分离,分离度符合要求,各辅料均无干扰,线性范围分别为1.012~404.800μg·mL^(-1)(r=0.9999)、1.117~223.400μg·mL^(-1)(r=0.9999)、1.180~471.800μg·mL^(-1)(r=0.9997)、0.605~605.200μg·mL^(-1)(r=0.9999);检测限分别为19.7、8.0、11.2、25.4 ng·mL^(-1);定量限分别为65.7、26.0、37.5、84.7 ng·mL^(-1);平均加样回收率分别为97.81%、98.30%、98.00%、101.10%,RSD分别为1.84%、1.39%、0.71%、1.98%(n=9)。结论所用方法稳定性、重复性均较好,通过测定甜味剂含量可监控制剂生产过程中辅料投料是否与处方一致,为儿童用药中甜味剂的质量控制提供了参考。

关键词：小儿氨酚黄那敏甜味剂安赛蜜糖精钠阿司帕坦甜菊苷一测多评高效液相色谱法含量测定

HMGB1及cD4^(+)/cD8^(+)比值对脓毒症急性肾损伤患者预后的诊断及与肾脏血流阻力指数的相关性分析

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首都食品与医药 2024年第2期31卷 48-51页

作者：孟宽张文芝广东省深圳市龙华区人民医院广东深圳518110

目的探讨HMGB1及cD4^(+)/cD8^(+)比值对脓毒症急性肾损伤(AKI)患者预后的诊断及与肾脏血流阻力指数之间的相关性分析。方法选取2021年1月-2023年1月在深圳市龙华区人民医院进行治疗的脓毒症患者60例,将患者分为非AK1组以及AK1组,每组30... 详细信息

目的探讨HMGB1及cD4^(+)/cD8^(+)比值对脓毒症急性肾损伤(AKI)患者预后的诊断及与肾脏血流阻力指数之间的相关性分析。方法选取2021年1月-2023年1月在深圳市龙华区人民医院进行治疗的脓毒症患者60例,将患者分为非AK1组以及AK1组,每组30例。检测患者的血清指标,分析对患者预后造成影响的因素以及其与肾脏血流阻力指数之间的相关性。结果经过对比,两组患者的年龄、性别无统计学差异(P>0.05),非AK1组的体质量指数、肾脏血流阻力指数明显低于AK1组(PcD4^(+)/cD8^(+)、c反应蛋白明显比AK1组要低,白蛋白明显比AK1组要高(PcD4^(+)/cD8^(+)以及c反应蛋白均是脓毒症AK1患者的预后影响因素(PcD4^(+)/cD8^(+)均对脓毒症AK1患者预后有一定的诊断价值,AUc分别为0.750、0.885,联合诊断的价值较高,AUc为0.985,相关性分析结果表明,HMGB1、cD4^(+)/cD8^(+)与肾脏血流阻力指数的相关性较高,有统计学差异(PcD4^(+)/cD8^(+)均是对脓毒症AK1患者预后造成影响的因素,可作为临床诊断标准进行推广使用。

关键词：脓毒症急性肾损伤 HMGB1 诊断

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轴承端面振动信号原位无线无源测量方法

轴承 2024年第6期 54-58页

作者：薛文智吴倩楠房志宏李晨中北大学省部共建动态测试技术国家重点实验室太原030051

为解决轴承端面加速度信号的原位测量问题,设计了一种用于轴承端面原位测量的无线无源振动加速度计。采用丝网印刷技术在轴承端面集成电感线圈,利用射频反射原理,通过改变电感线圈与接收天线的距离测量轴承端面的振动信号。搭建试验平... 详细信息

为解决轴承端面加速度信号的原位测量问题,设计了一种用于轴承端面原位测量的无线无源振动加速度计。采用丝网印刷技术在轴承端面集成电感线圈,利用射频反射原理,通过改变电感线圈与接收天线的距离测量轴承端面的振动信号。搭建试验平台并进行传感器性能验证的结果表明,在20~180 m/s^(2)加速度输入信号的激励下,所设计轴承端面无线无源振动传感器的输出信号与输入信号呈线性关系,传感器的灵敏度为0.120 7 mV/(m·s^(-2)),最大重复性误差不超过0.018%,可在高温高旋环境下进行陶瓷轴承外圈原位振动信号的测量。

关键词：滚动轴承陶瓷轴承原位测量振动传感器振动加速度射频无线