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Modelling tree mortality across diameter classes using mixedeffects zero-inflated models

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Journal of Forestry Research 2020年第1期31卷 131-140页

作者： Yang Li Xingang kang Qing Zhang Weiwei Guo Ministry of Education Key Laboratory for Silviculture and Conservation College of ForestryBeijing Forestry University

The mortality of trees across diameter class model is a useful tool for predicting changes in stand *** data commonly contain a large fraction of zeros and general discrete models thus show more *** on the traditional Poisson model and the negative binomial model,different forms of zero-inflated and hurdle models were applied to spruce-fir mixed forests data to simulate the number of dead *** comparing the residuals and Vuong test statistics,the zero-inflated negative binomial model performed best.A random effect was added to improve the model accuracy;however,the mixed-effects zero-inflated model did not show increased *** to the model principle,the zeroinflated negative binomial model was the most suitable,indicating that the"0"events in this study,mainly from the sample"0",i.e.,the zero mortality data,are largely due to the limitations of the experimental design and sample *** results also show that the number of dead trees in the diameter class is positively correlated with the number of trees in that class and the mean stand diameter,and inversely related to class size,and slope and aspect of the site.

关键词： Tree mortality Mixed forest Zero-inflated model Hurdle model Mixed-effects

Fabrication of Ti_3AlC_2 ceramic material by mechanical alloying

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Rare Metals 2010年第4期29卷 376-379页

作者： GUO Shibo kang Qiping LIU Jun QU Xuanhui College of Electromechanical Engineering Hunan University of Science and Technology Xiangtan 411201 China School of Materials Science andEngineering University of Science and Technology Beijing Beijing 100083 China

Ti3AlC2 has the properties of ceramics and metals. These excellent properties indicate that Ti3AlC2 is a very promising material to extensive applications. Ti3AlC2 ceramic material was prepared by mechanical alloying. The effects of milling time and sintering temperature on the fracture, microstmctttre and mechanical properties of Ti3AlC2 ceramic material were analyzed by laser particle analyzer, X-ray diffraction, and scanning electron microscopy. The experimental results showed that Ti3AlC2 had the best comprehensive properties after the composite powder was milled for 3 h and sintered at 1630℃ for 2 h. The relative density, bending strength, and hardness of the sample reached 92.23%, 345.2 MPa, and HRA 34.1, respectively. The fracture surface indicated that the fracture of the material belonged to ductile rapture.

关键词： mechanical alloying Ti3AlC2 microstructure mechanical properties

参芪降糖颗粒联合甲钴胺对妊娠糖尿病患者血糖及妊娠结局的影响

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国际医药卫生导报 2024年第17期30卷 2863-2867页

作者：张赞康辉雷立健延安大学咸阳医院产科咸阳712000 山西医科大学公共卫生学院流行病学教研室太原030001

目的探讨参芪降糖颗粒联合甲钴胺治疗对妊娠糖尿病患者血糖控制、妊娠结局的影响。方法选取2020年6月至2023年6月在延安大学咸阳医院进行治疗的妊娠糖尿病患者150例,采用随机数字表法分为中药组、西药组和联合治疗组,各50例。中药组年龄... 详细信息

目的探讨参芪降糖颗粒联合甲钴胺治疗对妊娠糖尿病患者血糖控制、妊娠结局的影响。方法选取2020年6月至2023年6月在延安大学咸阳医院进行治疗的妊娠糖尿病患者150例,采用随机数字表法分为中药组、西药组和联合治疗组,各50例。中药组年龄(29.33±3.65)岁,孕周(29.75±3.22)周,在常规治疗基础上给予参芪降糖颗粒(1 g/次,3次/d)治疗;西药组年龄(29.16±3.06)岁,孕周(30.51±3.41)周,在常规治疗基础上给予甲钴胺(0.5 mg/次,3次/d)治疗;联合治疗组年龄(30.21±3.16)岁,孕周(30.81±3.36)周,在常规治疗基础上给予参芪降糖颗粒(1 g/次,3次/d)和甲钴胺(0.5 mg/次,3次/d)治疗,3组均给药治疗1个月。比较3组患者的临床疗效、血糖达标率、血糖与血脂相关指标水平及妊娠结局。统计学方法采用F检验、t检验、χ^(2)检验。结果中药组的总有效率为70.00%(35/50),西药组的总有效率为74.00%(37/50),联合治疗组的总有效率为94.00%(47/50),3组比较差异有统计学意义(χ^(2)=7.523,P<0.05)。治疗1个月后,联合治疗组的糖化血红蛋白(HbA1c)、餐后2 h血糖(2hBG)、空腹血糖(FBG)、胱抑素C(Cys-C)、同型半胱氨酸(Hcy)水平均低于中药组和西药组[(5.02±0.63)%比(6.33±0.79)%比(6.21±0.96)%、(4.02±0.53)mmol/L比(5.96±0.75)mmol/L比(5.83±0.82)mmol/L、(5.69±0.62)mmol/L比(7.36±0.95)mmol/L比(6.91±0.77)mmol/L、(8.33±0.95)μmol/L比(11.02±1.20)μmol/L比(10.86±1.25)μmol/L、(1.01±0.11)mg/L比(1.31±0.16)mg/L比(1.28±0.15)mg/L],3组比较差异均有统计学意义(均P<0.05)。联合治疗组的妊娠不良结局发生率均低于中药组和西药组[8.00%(4/50)比30.00%(15/50)比29.00%(14/50)]。联合治疗组的血糖达标率、顺产率高于中药组及西药组[94.00%(47/50)比70.00%(35/50)比74.00%(37/50)、70.00%(35/50)比40.00%(20/50)比44.00%(22/50)],3组比较差异均有统计学意义(均P<0.05)。结论参芪降糖颗粒联合甲钴胺治疗可降低妊娠糖尿病患者的血糖水平,改善不良妊娠结局。

关键词：妊娠糖尿病参芪降糖颗粒甲钴胺血糖控制妊娠结局

参麦润目方联合玻璃酸钠滴眼液治疗睑板腺功能障碍干眼症临床研究

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新中医 2024年第17期56卷 98-102页

作者：方燕郑志刚郑康温州医科大学附属衢州医院/衢州市人民医院浙江衢州324000

目的:观察参麦润目方联合玻璃酸钠滴眼液治疗睑板腺功能障碍(MGD)干眼症的临床疗效。方法:抽取104例MGD干眼症患者,按照随机数字表法随机分为联合组和西医组各52例。西医组接受玻璃酸钠滴眼液治疗,联合组接受参麦润目方联合玻璃酸钠滴... 详细信息

目的:观察参麦润目方联合玻璃酸钠滴眼液治疗睑板腺功能障碍(MGD)干眼症的临床疗效。方法:抽取104例MGD干眼症患者,按照随机数字表法随机分为联合组和西医组各52例。西医组接受玻璃酸钠滴眼液治疗,联合组接受参麦润目方联合玻璃酸钠滴眼液治疗,连续治疗4周。比较2组临床疗效及不良反应,比较2组治疗前后中医证候积分、眼表疾病指数(OSDI)评分、泪膜稳定性、MGD程度。结果:联合组总有效率94.23%,高于西医组78.85%(P0.05)。结论:参麦润目方联合玻璃酸钠滴眼液治疗MGD干眼症效果良好,可进一步减轻症状,提升泪膜稳定性,且安全性良好。

关键词：干眼症睑板腺功能障碍参麦润目方玻璃酸钠滴眼液泪膜稳定性中医证候积分

粉防己地上部分化学成分及其潜在作用靶点及活性研究

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中成药 2024年第9期46卷 2980-2986页

作者：薛佳芸郭弯康云黄建明汪亚勤复旦大学药学院上海201203

目的研究粉防己Stephania tetrandra ***地上部分的化学成分并预测其潜在作用靶点和活性。方法粉防己地上部分70%乙醇提取物采用大孔树脂、硅胶、Sephadex LH-20、半制备HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构... 详细信息

目的研究粉防己Stephania tetrandra ***地上部分的化学成分并预测其潜在作用靶点和活性。方法粉防己地上部分70%乙醇提取物采用大孔树脂、硅胶、Sephadex LH-20、半制备HPLC进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。利用PharmMapper平台预测化合物的潜在作用靶点及活性。结果从中分离得到11个化合物,分别鉴定为6 S,6a S-N-neolitsine N_(α)-oxide(1)、新木姜子素(2)、荷包牡丹碱(3)、南天宁碱(4)、氧化南天宁碱(5)、oxophoebine(6)、N-乙酰去甲荷包牡丹碱(7)、鹅掌楸碱(8)、6 R,6a S-N-nantenine N_(β)-oxide(9)、氧化克班宁(10)、stigmast-4-ene-6β-ol-3-one(11)。化合物的潜在靶点包括胰腺素样生长因子1受体和转甲状腺素蛋白。结论化合物1为新化合物,化合物6、8~11为首次从该植物中分离得到。化合物1~11具有抑制多种肿瘤细胞的潜在活性。

关键词：粉防己地上部分化学成分分离鉴定作用靶点 PharmMapper

Magnetic properties and magnetocaloric effects of Gd65（Cu,Co,Mn）35 amorphous ribbons

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Journal of Materials Science & Technology 2019年第10期35卷 2283-2287页

作者： Peng Jia Leipeng Duan kang Wang Engang Wang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819China School of Metallurgy Northeastern UniversityShenyang110819China

The magnetic phase transition and magnetocaloric effects of Gd65(Cu,Co,Mn)35 amorphous ribbons were investigated. The increased Mn substitution for Co or Mn substitution for Cu led into a higher secondorder magnetic phase transformation temperature, near 200 K in all ribbons. Under the field change of 7T, a maximum entropy change(Sm max) of 6 J kg^-1K^-1 was achieved in Gd(65)Cu10Co20Mn5 ribbon and slightly dependent on the compositions. With varied composition, a full width at half of Sm maxwas greatly widened to be over than 180 K for Gd65Cu15Co10Mn(10) ribbon. The refrigeration capacity was also greatly enhanced to 1000J kg^-1 for Gd65Cu20Co10Mn5 ribbon, which was even excellent compared with other Gd-based amorphous systems.

关键词： Phase transition Magnetocaloric effect Refrigeration capacity Amorphous ribbon Gd-based ribbon

Discrete Capability of the Lempel-Ziv Complexity Algorithm on a Vibration Sequence

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Chinese Physics Letters 2010年第6期27卷 20-23页

作者： LI Jian-kang SONG Xiang-Rong YIN Ke Department of Engineering Mechanics Faculty of Science Jiangsu University Zhenjiang 212013 School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Zhenjiang 212003

The Lempel Ziv complexity （LZC） method is used to analyze the acceleration response of the T-shaped plate. The response is converted into symbolic sequences with the multi-segmented coarse-grained method. The LZC of the response of 240 points located in different areas near the center is calculated. The results show that LZC arithmetic applied to elastomer vibration can satisfy the discreteness condition.

关键词： COMPUTATIONAL complexity VIBRATION (Mechanics) ALGORITHMS ACCELERATION (Mechanics) ELASTOMERS PLATES (Engineering)

Terahertz wave generation from ring-Airy beam induced plasmas and remote detection by terahertz-radiation- enhanced-emission-of-fluorescence: a review

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Frontiers of Optoelectronics 2019年第2期12卷 117-147页

作者： kang LIU Pingjie HUANG Xi-Cheng ZHANG The Institute of Optics University of Rochester Rochester NY14627USA State Key Laboratory of Industrial Control Technology College of Control Science and Engineering Zhejiang University Hangzhou 310027China The Beijing Advanced Innovation Centerfor Imaging Technology Capital Normal University Beijing 100037China

With the increasing demands for remote spectroscopy in many fields ranging from homeland security to environmental monitoring, terahertz (THz) spectroscopy has drawn a significant amount of attention because of its capability to acquire chemical spectral signatures non-invasively. However, advanced THz remote sensing techniques are obstructed by quite a few factors, such as THz waves being strongly absorbed by water vapor in the ambient air, difficulty to generate intense broadband coherent THz source remotely, and hard to transmit THz waveform information remotely without losing the signal to noise ratio, etc. In this review, after introducing different THz air-photonics techniques to overcome the difficulties of THz remote sensing, we focus mainly on theoretical and experimental methods to improve THz generation and detection performance for the purpose of remote sensing through tailoring the generation and detection media, air-plasma. For the THz generation part, auto-focusing ring-Airy beam was introduced to enhance the THz wave generation yield from two-color laser induced air plasma. By artificially modulated exotic wave packets, it is exhibited that abruptly auto-focusing beam induced air-plasma can give an up to 5.3-time-enhanced THz wave pulse energy compared to normal Gaussian beam induced plasma under the same conditions. At the same time, a red shift on the THz emission spectrum is also observed. A simulation using an interference model to qualitatively describe these behaviors has be developed. For the THz detection part, the results of THz remote sensing at 30 m using THz-radiation-enhanced-emission- of-fluorescence (THz-REEF) technique are demonstrated, which greatly improved from the 10 m demonstration last reported. The THz-REEF technique in the counter-propagation geometry was explored, which is proved to be more practical for stand-off detections than co-propagation geometry. We found that in the counter- propagating geometry the maximum amplitude

关键词： ultrafast terahertz (THz) techniques THz air- photonics ring-Airy beams THz-radiation-enhanced-emis- sion-of-fluorescence (THz-REEF) of air-plasma in co- propagation geometry THz-REEF of air-plasma in coun-ter-propagation geometry

从肠道微生物源性细胞外囊泡角度探究电针对营养型肥胖小鼠肠道菌群结构及功能的影响

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肠外与肠内营养 2024年第2期31卷 65-72页

作者：王显云司原成高璐琪李志菊康朝霞贵州中医药大学针灸推拿学院贵州贵阳550025

目的:从肠道微生物源性的细胞外囊泡探讨电针对食源性肥胖小鼠肠道菌群的调控作用。方法:建立营养性肥胖模型,将造模成功的肥胖鼠随机分成模型组和电针组各10只,电针组针刺中脘、关元、天枢及足三里四个穴位。干预结束后取各组小鼠粪便... 详细信息

目的:从肠道微生物源性的细胞外囊泡探讨电针对食源性肥胖小鼠肠道菌群的调控作用。方法:建立营养性肥胖模型,将造模成功的肥胖鼠随机分成模型组和电针组各10只,电针组针刺中脘、关元、天枢及足三里四个穴位。干预结束后取各组小鼠粪便,采用超速离心法分离细胞外囊(EV)。透射电镜鉴定EV,提取EV中微生物DNA,通过16S rRNA的测序技术对其关联的肠道菌群进行分析。结果:电针干预治疗后肥胖鼠体质量及Lee’s指数显著下降(P <0.01),透射电镜图显示粪便中提取的EV呈圆形或椭圆形双层膜的囊泡状结构,16S rRNA测序分析显示在门水平上,模型组变形菌门细菌相对丰度显著高于正常组(P <0.05),而厚壁菌门、拟杆菌门的丰度均明显降低(P <0.05)。在属水平上,模型组嗜冷杆菌属、游动球菌属的相对丰度均显著高于正常组(P <0.01),而土壤芽孢杆菌属、假单胞菌属、变形杆菌、乳杆菌属、农杆菌、肠杆菌属、短波单胞菌、丛毛单胞菌属细菌丰度均低于正常组(P <0.05)。电针干预后,实验鼠肠道微生物多样性增加,菌群结构向正常小鼠靠拢。结论:营养性肥胖小鼠肠道菌群结构变化伴随肠道微生物源性EV谱的变化,16S rRNA测序分析表明,肠道微生物源性EV中微生物DNA反映了肠道微生物群的组成,电针治疗肥胖不仅与调控肠道菌群有关,还与肠道微生物源性EV密切相关。

关键词：电针肥胖细胞外囊泡肠道菌群 16S rRNA测序