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natural forests in new Zealand–a large terrestrial carbon pool in a national state of equilibrium

Forest Ecosystems 2021年第3期8卷 458-478页

作者： Thomas Paul Mark O.Kimberley Peter n.Beets Scion Private Bag 3020Rotorua 3046New Zealand Environmental Statistics Ltd Whangapararoa 0930New Zealand retired(previously Scion) Rotorua 3010New Zealand

Background:natural forests cover approximately 29%of new Zealand’s landmass and represent a large terrestrial carbon *** 2002 new Zealand implemented its first representative plot-based natural forest inventory to assess carbon stocks and stock changes in these mostly undisturbed old-growth *** previous studies have provided estimates of biomass or carbon stocks,these were either not fully representative or lacked data from important pools such as dead wood(coarse woody debris).The current analysis provides the most complete estimates of carbon stocks and stock changes in natural forests in new ***:We present estimates of per hectare carbon stocks and stock changes in live and dead organic matter pools excluding soil carbon based on the first two measurement cycles of the new Zealand natural Forest Inventory carried out from 2002 to *** show that new Zealand’s natural forests are in balance and are neither a carbon source nor a carbon *** average total carbon stock was 227.0±14.4 tc·ha^(−1)(95%c.I.)and did not change signific.ntly in the 7.7 years between measurements with the net annual change estimated to be 0.03±0.18 tc·ha^(−1)·yr^(−1).There was a wide variation in carbon stocks between forest *** forest had an averaged carbon stock of only 53.6±9.4 tc·ha^(−1) but had a signific.nt sequestration rate of 0.63±0.25 tc·ha^(−1)·yr^(−1),while tall forest had an average carbon stock of 252.4±15.5 tc·ha^(−1),but its sequestration rate did not differ signific.ntly from zero(−0.06±0.20 tc·ha^(−1)·yr^(−1)).The forest alliance with the largest average carbon stock in above and below ground live and dead organic matter pools was silver beech-red beech-kamahi forest carrying 360.5±34.6 tc·ha^(−1).Dead wood and litter comprised 27%of the total carbon ***:new Zealand’s natural Forest Inventory provides estimates of carbon stocks including estimates for difficult to measure pools such as dead wood and roots.I

关键词： Forest inventory natural forests carbon stocks and change Terrestrial carbon pool

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高速公路出入口运动车辆轨迹分层聚类算法

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吉林大学学报（工学版） 2017年第6期47卷 1696-1702页

作者：孙宗元方守恩同济大学道路与交通工程教育部重点试验室上海201804

为了提高对高速公路出入口车辆运动行为的理解和分析水平,根据出入口车辆运动轨迹的时空特征,提出了一种运动轨迹层次聚类算法。结合出入口轨迹方向一致、长短不一的特点,提出采用改进Hausdorff距离来衡量轨迹间的相似性。建立了改进模... 详细信息

为了提高对高速公路出入口车辆运动行为的理解和分析水平,根据出入口车辆运动轨迹的时空特征,提出了一种运动轨迹层次聚类算法。结合出入口轨迹方向一致、长短不一的特点,提出采用改进Hausdorff距离来衡量轨迹间的相似性。建立了改进模糊c均值轨迹分层聚类算法,首先根据轨迹的空间几何位置进行路径聚类,然后根据车辆的速度信息对已有路径聚类进一步聚类获得具有时空区分度的最终结果。真实高速公路出入口的试验结果表明:本文提出的轨迹聚类算法对于场景固定运动行为模式不仅具有较强的适用性,而且能够保障聚类结果的准确性和可靠性。

关键词：交通运输系统工程高速公路出入口轨迹分析改进Hausdorff距离聚类算法

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PD-L1 is increased in the spinal cord and infiltrating lymphocytes in experimental allergic encephalomyelitis

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neural Regeneration Research 2013年第35期8卷 3296-3305页

作者： Min Li Jiandong Jiang Bing Fu Jiechun chen Qun Xue Wanli Dong Yanzheng Gu Lingtao Tang Limin Xue Qi fang Mingyuan Wang Xueguang Zhang Department of neurology Second People's Hospital of Lianyungang City Department of neurology First Affiliated Hospital of Soochow University Institute of clinical Immunology Soochow University Department of neurology Third Hospital of Xingtai City Red-cross Blood c.nter of Suzhou city

Experimental allergic encephalomyelitis is a mouse model of human multiple sclerosis with similar pathology and pathogenesis. Thl cells play an important role in the pathogenesis of experimental allergic encephalomyelitis. This study determined the potential effect of programmed cell death 1 ligand 1 in the pathogenesis of experimental allergic encephalomyelitis induced by injecting myelin oligodendrocyte glycoprotein, complete Freund＇s adjuvant and Bordetella pertussis toxin into c57BL/6J mice. Experimental allergic encephalomyelitis mice developed disease and showed in- flammatory changes in the c.ntral nervous system by hematoxylin-eosin staining of spinal cord pathological sections, demyelination by Luxol fast-blue staining and clinical manifestations. The expression of programmed cell death 1 ligand 1 in mice was detected by immunohistochemistry, flow cytometry and western blot anatysis. The expression of programmed cell death 1 ligand 1 in the spinal cord and splenocytes of mice was signific.ntly increased compared with normal mice. Our findings suggest the involvement of programmed cell death 1 ligand 1 in the pathogenesis of ex- perimental allergic encephalomyelitis and suggest this should be studied in multiple sclerosis.

关键词： neural regeneration experimental allergic encephalomyelitis multiple sclerosisautoimmune disease costimulatory signal costimulatory molecule programmed ce1 B7-cD28 superfamily grants-supported paper neuroregenerationanimal models II death 1 ligand

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comparison of corneal biomechanics among primary open-angle glaucoma with normal tension or hypertension and c.ntrols

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chinese Medical Journal 2021年第9期134卷 1087-1092页

作者： Ya-Hui Wei Yu cai Bonnie n.K.choy Bai-Bing Li Ruo-Shi Li chen Xing Xia Wang Tian Tian Yuan fang Mei Li Ying-Zi Pan Department of Ophthalmology Peking University First HospitalBeijing 100034China Department of Ophthalmology LKS Faculty of MedicineThe University of Hong KongHong KongChina Department of Ophthalmology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

Background:normal tension glaucoma(nTG)is a less pressure-dependent type of glaucoma with characteristic optic ***,the biomechanical mechanism has been thought to account for glaucomatous optic.neuropathy to some *** intended to compare dynamic corneal response parameters(DcRs)among patients with primary open-angle glaucoma with normal tension or hypertension and *** correlations between DcRs and known risk factors for glaucoma were also ***:In this cross-sectional study,49 nTG subjects,45 hypertension glaucoma(HTG)subjects,and 50 c.ntrol subjects were *** compared the differences in DcRs using corneal visualization Scheimpflug tec.nology among the nTG,HTG,and c.ntrol *** also analyzed the correlations between DcRs and known risk factors for glaucoma(eg,c.ntral corneal thic.ness[ccT],intraocular pressure[IOP],etc).Results:The maximum inverse c.ncave radius(nTG:0.18[0.17,0.20]mm-1;c.ntrol:0.17[0.16,0.18]mm-1;P=0.033),deformation amplitude ratio of 2 mm(DAR 2 mm,nTG:4.87[4.33,5.39];c.ntrol:4.37[4.07,4.88];Pnd DAR 1 mm(nTG:1.62[1.58,1.65];c.ntrol:1.58[1.54,1.61];Pnific.ntly higher in nTG than in the *** integrated radius(IR,nTG:8.40±1.07 mm-1;HTG:7.64±1.31 mm-1;P=0.026)and DAR 2 mm(nTG:4.87[4.33,5.39];HTG:4.44[4.12,5.02];Pnific.ntly higher,whereas the stiffness parameter at the first applanation(SP-A1,nTG:91.23[77.45,107.45];HTG:102.36[85.77,125.12];P=0.007)was lower in nTG than in *** were no signific.nt differences in the DcRs between HTG and c.ntrol groups(P>0.05).In the univariate and multivariate analyses,some of the DcRs,such as IR,were negatively correlated with ccT and IOP,whereas SP-A1 was positively correlated with ccT and ***:The cornea was more deformable in nTG than in HTG or *** were no signific.nt differences in corneal deformability between HTG and *** cornea was more deformable with the thinner cornea and lower

关键词： corneal biomechanics Primary open-angle glaucoma normal tension glaucoma Hypertensive glaucoma

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Helicobacter pylori and crohn's disease: A retrospective single-c.nter study from china

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World Journal of Gastroenterology 2013年第28期19卷 4576-4581页

作者： Zun Xiang Yi-Peng chen Yue-fang Ye Kui-Fen Ma Shao-Hua chen Lin Zheng Yi-Da Yang Xi Jin Department of Gastroenterology the First Affiliated Hospital College of Medicine Zhejiang University Department of Gastroenterology the Affiliated Hospital College of Medicine Hangzhou Normal University Department of Pharmacy the First Affiliated Hospital College of Medicine Zhejiang University Department of Infectious Disease the First Affiliated Hospital College of Medicine Zhejiang University

AIM: To investigate the association between Helicobacter pylori (H. pylori ) infection and the prevalence of crohn's disease (cD). METHODS: Subjects were selected from patients admitted the gastrointestinal (GI) department at The First Affiliated Hospital School of Medic.ne (Zhejiang University)for abdominal pain, hematochezia, diarrhea and other GI symptoms between January 2008 and September 2012. cD was diagnosed by endoscopy and biopsy. H. pylori infection was detected by a 14 c-urea breath test and culturing of the biopsy sample. Demographic, anthropometric and serologic data were collected for each patient. H. pylori infection rate was compared between cD and c.ntrol groups, followed by a subgroup analysis based on extent and severity of cD. Student's t , Mann-Whiney U , and χ 2 tests were used to analyze the data. RESULTS: A total of 447 patients were analyzed, including 229 in the cD group and 248 in the c.ntrol group. There were no signific.nt differences in age, sex, and rates of hypertension or diabetes. However, the cD group showed signific.ntly higher rates of smoking history (34.9% vs 18.1%), alcohol intake (17.4% vs 8.1%), white blood cell count (9.7 ± 2.9 × 10 9 /L vs 4.3 ± 0.9 × 10 9 /L), and c-reactive protein (36.3 ± 20.8 mg/L vs 5.5 ± 2.3 mg/L) but lower body mass index (24.5 ± 2.0 kg/m 2 vs 26.0 ± 2.2 kg/m 2 ) than the c.ntrol group. The H. pylori infection rate in the cD group was 27.1%, signific.ntly lower than that of 47.9% in the c.ntrol group. Furthermore, the H. pylori infection rates in patients with colonic, small intestine, ileocolonic and extensive cD were 31.1%, 28.9%, 26.8% and 25.9% respectively, all of which were signific.ntly lower than in the c.ntrol group. Finally, the H. pylori infection rates in patients with remission, moderate and severe cD were 34.3%, 30.7% and 22.0% respectively, which were also signific.ntly lower than in the c.ntrol group. c.ncLUSIOn: Lower H. pylori infection in cD patients suggests a correlation between

关键词： crohn’s disease Helicobacter pylori Urea breath test Biopsy Pathogenesis Inflammatory bowel disease Bacteria

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数字全息显微中的相位像差自动补偿算法

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东北大学学报（自然科学版） 2020年第11期41卷 1591-1595页

作者：马树军方锐东北大学机械工程与自动化学院辽宁沈阳110819

结合图像分割技术提出了一种用于数字全息显微成像的相位像差自动补偿算法.首先,采用最小二乘拟合算法对包含被测物体的解包裹相位图进行粗略的补偿,在此基础上,利用图像分割算法对其背景区域进行分割,获得不含被测物体的解包裹相位图.... 详细信息

结合图像分割技术提出了一种用于数字全息显微成像的相位像差自动补偿算法.首先,采用最小二乘拟合算法对包含被测物体的解包裹相位图进行粗略的补偿,在此基础上,利用图像分割算法对其背景区域进行分割,获得不含被测物体的解包裹相位图.最后,对其进行最小二乘拟合从而实现相位像差的精确补偿.传统的数字全息显微技术需要通过手工检测背景区域来解决相位像差补偿的问题.然而,本文方法既不需要人工干预,也不需要光学设置的先验知识,即可实现相位像差的自动补偿.通过搭建的数字全息显微实验平台验证了所提算法的可行性和准确性.

关键词：图像分割数字全息显微像差补偿解包裹相位图最小二乘拟合

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基于湿效应ce-La/TiO_2空心微球制备及光-湿性能

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浙江大学学报（工学版） 2017年第2期51卷 304-311页

作者：尚建丽宗志芳西安建筑科技大学材料与矿资学院陕西西安710055

以TiO_2作为研究对象,选取不同表面活性剂与改性剂,采用溶胶-凝胶法制备ce-La/TiO_2空心微球.利用环境测试舱、等温吸放湿法、扫描电镜(SEM)、X射线衍射仪(XRD)、紫外可见分光光度计(UV-Vis)、氮吸附(BET)和激光粒度仪(LPSA)对TiO_2空... 详细信息

以TiO_2作为研究对象,选取不同表面活性剂与改性剂,采用溶胶-凝胶法制备ce-La/TiO_2空心微球.利用环境测试舱、等温吸放湿法、扫描电镜(SEM)、X射线衍射仪(XRD)、紫外可见分光光度计(UV-Vis)、氮吸附(BET)和激光粒度仪(LPSA)对TiO_2空心微球进行性能测试与表征,分析表面活性剂与改性剂对TiO_2空心微球性能的影响.结果表明,聚乙烯吡咯烷酮(PVP)作为表面活性剂、ce-La作为改性剂,不仅有利于TiO_2与SiO2的界面分离,形成较好微观形貌;还促使晶粒尺寸减小与比表面积增加,提高吸放湿性能;而且增加光子的利用效率,促使吸收边带红移,提高对可见光源的响应能力.ce-La/TiO_2微球具有良好的空心结构且以开放圆筒孔为主,表现出较好的吸放湿性能,在相对湿度为84.3%时的平衡含湿量达到0.242 3g/g;同时兼具较好的光催化性能,经过6h对甲醛气体的降解效率达到52%.

关键词： TiO2 空心微球调湿性能光催化 ce-La

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Generation of passively Q-switched fiber laser at 1 μm by using MoSSe as a saturable absorber

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chinese Optics Letters 2017年第2期15卷 15-19页

作者： H. Ahmad S. A. Reduan S. n. Aidit Z. c. Tiu Photonics Research c.ntre University of Malaya Kuala Lumpur 50603 Malaysia

Passively Q-switched ytterbium-doped fiber lasers （YDFLs） incorporating a molybdenum sulfide selenide （MoSSe）-based saturable absorber （SA） are demonstrated. The modulation depth and saturation intensity of the MoSSe-based SA are measured to be approximately 25.0% and 0.002 MW/cm^2, respectively, using the twin detector tec.nique. The YDFL＇s output has a c.nter wavelength of 1038.5 nm with a top pulse width and energy of 1.2 μs and 18.9 nJ, respectively, at a pump power of 333 mW. The MoSSe-based SA has a good linear optical response, providing signific.nt opportunity for use in applications over an ultra-broadband spectrum, particularly spectroscopy and biomedical diagnostics.

关键词： Mo Generation of passively Q-switched fiber laser at 1 m by using Mo SSe as a saturable absorber SA

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Prostaglandin E1 protects hepatocytes against endoplasmic reticulum stress-induced apoptosis via protein kinase A-dependent induction of glucose-regulated protein 78 expression

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World Journal of Gastroenterology 2017年第40期23卷 7253-7264页

作者： fang-Wan Yang Yu Fu Ying Li Yi-Huai He Mao-Yuan Mu Qi-chuan Liu Jun Long Shi-De Lin Department of Infectious Diseases Affiliated Hospital of Zunyi Medical College Department of Infectious Diseases Heze Municipal Hospital

AIM To investigate the protective effect of prostaglandin E1(PGE1) against endoplasmic reticulum(ER) stressinduced hepatocyte apoptosis, and to explore its underlying *** Thapsigargin(TG) was used to induce ER stress in the human hepatic cell line L02 and hepatocarc.nomaderived cell line Hep G2. To evaluate the effects of PGE1 on TG-induced apoptosis, PGE1 was used an hour prior to TG treatment. Activation of unfolded protein response signaling pathways were detected by western blotting and quantitative real-time RTPcR. Apoptotic index and cell viability of L02 cells and Hep G2 cells were determined with flow cytometry and MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium] assay. RESULTS Pretreatment with 1 μmol/L PGE1 protected against TG-induced apoptosis in both L02 cells and Hep G2 cells. PGE1 enhanced the TG-induced expression of c/EBP homologous protein(cHOP), glucose-regulated protein(GRP) 78 and spliced X box-binding protein 1 at 6 h. However, it attenuated their expressions after 24 h. PGE1 alone induced protein and m RnA expressions of GRP78; PGE1 also induced protein expression of DnA damage-inducible gene 34 and inhibited the expressions of phospho-PKR-like ER kinase, phosphoeukaryotic initiation factor 2α and cHOP. Treatment with protein kinase A(PKA)-inhibitor H89 or KT5720 blocked PGE1-induced up-regulation of GRP78. Further, the cytoprotective effect of PGE1 on hepatocytes was not observed after blockade of GRP78 expression by H89 or small interfering RnA specifically targeted against human *** Our study demonstrates that PGE1 protects against ER stress-induced hepatocyte apoptosis via PKA pathwaydependent induction of GRP78 expression.

关键词： Hepatocytes Endoplasmic reticulum stress Thapsigargin Glucose-regulated protein 78 Protein kinase A Apoptosis

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无缓存片上网络中偏转感知的拥塞控制方法

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计算机辅助设计与图形学学报 2015年第3期27卷 542-547页

作者：方娟姚治成北京工业大学计算机学院北京100124

针对现有工作仅对高网络密集度应用的注入率进行调控,无法精确地控制网络拥塞的问题,提出一种偏转感知的拥塞控制方法——DAT.该方法使用分布式的偏转监控表来追踪网络中偏转数据包的分布,从而快速准确地确定拥塞源;并结合网络利用率确... 详细信息

针对现有工作仅对高网络密集度应用的注入率进行调控,无法精确地控制网络拥塞的问题,提出一种偏转感知的拥塞控制方法——DAT.该方法使用分布式的偏转监控表来追踪网络中偏转数据包的分布,从而快速准确地确定拥塞源;并结合网络利用率确定拥塞源向网络中注入数据包的速率,以达到缓解网络拥塞提高网络整体性能的目的.在16核仿真平台上对DAT方法的评测结果显示,相比于基准无缓存no c,文中方法可以将网络偏转率平均降低8.6%,并且具有良好的可扩展性和较低的硬件开销.

关键词：多核片上网络拥塞控制

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