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西藏麦地卡湿地的浮游植物——2.功能群特征及其与环境因子的关系

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湖泊科学 2022年第4期34卷 1115-1126页

作者：潘成梅刘洋安瑞志巴桑西藏大学理学院青藏高原湿地与流域生态实验室拉萨850000

为揭示青藏高原湿地浮游植物功能群时空分布特征与环境因子的关系,本文于2019年7月(丰水期)和2019年10月(枯水期)在麦地卡湿地调查浮游植物功能群组成和生物量,并运用Spearman相关性分析、冗余分析(RDA)和典范对应分析(CCA)等方法,对麦... 详细信息

为揭示青藏高原湿地浮游植物功能群时空分布特征与环境因子的关系,本文于2019年7月(丰水期)和2019年10月(枯水期)在麦地卡湿地调查浮游植物功能群组成和生物量,并运用Spearman相关性分析、冗余分析(RDA)和典范对应分析(CCA)等方法,对麦地卡湿地浮游植物功能群时空分布特征及其与环境因子的关系进行分析.结果表明:1)根据功能群分类方法,麦地卡湿地浮游植物可划分为27个功能群,分别为A、B、C、D、E、f.G、H1、J、K、L_(M)、L_(O)、M、MP、N、P、S1、S2、T、T B、T C、W1、W2、X1、X2、X3和Z;在时间维度上,丰水期有26个功能群,枯水期有23个功能群;在空间维度上,河流湿地有24个功能群,湖泊湿地有23个功能群,沼泽湿地有12个功能群.2)丰水期,以功能群A、D、L M、L_(O)、MP、N、P、T、T B和X3为主,枯水期以功能群A、D、J、L_(M)、L O、MP、N、P、T和T B为主,其中A和T功能群为2个水情期的共有绝对优势功能群,功能群J仅为枯水期的绝对优势功能群.3)生态状态指数(Q)范围为1.80~4.86,平均值为3.80,表明麦地卡湿地水质状态为“好”.4)相关性分析表明,浊度、COD Cr、总磷和硝态氮与部分优势功能群生物量具有显著相关性;RDA分析表明,盐度和总氮是影响丰水期优势功能群生物量的主要环境因子.CCA分析表明,总氮和硝态氮是影响枯水期优势功能群生物量的主要环境因子.

关键词：麦地卡湿地浮游植物功能群环境因子时空分布

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良性肾上腺源性库欣综合征临床特点比较分析

中国实用内科杂志 2024年第2期44卷 134-139页

作者：苗新宇林璐李乐乐窦京涛陈康吕朝晖巴建明裴育谷伟军杜锦郭清华王先令臧丽李一君闫文华李春霖母义明中国人民解放军总医院第一医学中心内分泌科北京100853 中国人民解放军总医院第二医学中心内分泌科国家老年疾病临床医学研究中心北京100853 海南省人民医院内分泌科海南海口570311 首都医科大学附属北京儿童医院内分泌遗传代谢科国家儿童医学中心北京100045

目的比较分析具有显性库欣综合征临床表现的肾上腺皮质腺瘤(ADA)、双侧肾上腺大结节增生(BMAH)和原发性色素性结节样肾上腺皮质病(PPNAD)患者临床特点,为临床鉴别诊断提供依据。方法回顾性分析2008—2020年于解放军总医院住院明确诊断为... 详细信息

目的比较分析具有显性库欣综合征临床表现的肾上腺皮质腺瘤(ADA)、双侧肾上腺大结节增生(BMAH)和原发性色素性结节样肾上腺皮质病(PPNAD)患者临床特点,为临床鉴别诊断提供依据。方法回顾性分析2008—2020年于解放军总医院住院明确诊断为ADA患者86例、BMAH患者23例、PPNAD患者7例的临床资料。结果(1)三组患者BMAH组年龄最大,平均(51.7±9.5)岁,ADA次之,PPNAD组就诊年龄最小,平均(19.9±5.7)岁。ADA、PPNAD组患者女性居多,BMAH患者男女比例相当。(2)临床表现方面,PPNAD组紫纹最多(71.4%),多血质、瘀斑、满月脸、向心性肥胖及皮肤变薄等方面差异无统计学意义。(3)合并症方面,BMAH组糖代谢异常和血脂紊乱患者最多(分别为87.0%、68.2%),三组患者均合并较高比例的骨质疏松或低骨量(>75%)。BMAH组收缩压、糖化血红蛋白、血甘油三酯及血钠水平更高(Pf.水平,三组患者基线血ACTH均明显受抑制,血f.24 h尿游离皮质醇(Uf.)显著升高,组间差异无统计学意义(P>0.05)。PPNAD组小、大剂量地塞米松抑制试验后24 h Uf.水平较基线显著升高(Pf.显著升高的特点。

关键词：库欣综合征非ACTH依赖皮质腺瘤双侧肾上腺大结节增生原发性色素性结节样肾上腺皮质疾病

Crystal Structures of. Two New Monoprotonated Products of.1,4,7 trimethyl-1,4,7-triazacyclononane: （Me3〔9〕aneN3H）(SO3Cf.) and （Me3〔9〕aneN3H）I

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Chinese Journal of.Structural Chemistry 2000年第1期19卷 48-52页

作者： DENG Dao Lia * ZHANG Yan Hui a DAI Cong Yun a ZENG Hong a YAN Zhi Qing a YE Chang Qing a Ronald Ha\|Ge ba (Unilever Research SIOC, 354 f.nglin Road, Shanghai 200032. China) b (Unilever Research Laboratorium, Olivier van Noor Unilever Research SIOC 上海 2 0 0 0 32 Unilever Research Laboratorium 荷兰 Vlaardinge

Two new monoprotonated products of.macrocyclic polyamine 1,4,7 trimethyl 1,4,7 triazacyclononane(Me 3〔9〕aneN 3), (Me 3〔9〕aneN 3H)(SO 3Cf.3) 1 (C 10 H 22 N 3O 3Sf.3, M r =321.36) and (Me 3〔9〕aneN 3H)I 2 (C 9H 22 N 3I, M r =299.20) were obtained by the reactions of.Me 3〔9〕aneN 3 and yttrium trif.ate or ytterbium diiodide as the unexpected products. The crystal structures of.compounds 1 and 2 have been determined. Crystal 1 is orthorhombic, space group P2 12 12 1(#19), a =12.609(3), b=13.531(1), c=9.225(3) , V=1573.9(7)  3, Z=4, D c= 1.356 g/cm 3, μ =2.47 cm -1 , f.(000)=680 and R=0.052, R w =0.052 f.r 807 unique ref.ections with I>2σ(I) . Crystal 2 belongs to the orthorhombic system with space group P2 12 12 1(#19), a=11.417(2), b=13.099(3), c=8.762(2) , V=1310.5(4)  3, Z=4, D c =1\^516 g/cm 3, μ =24.14 cm -1 , f.(000)=600 and R=0.035, R w =0.042 f.r 1427 unique ref.ections with I>3σ(I) . The two structures contain the same cyclic f.amework in which the acid proton is bonded to an amine nitrogen. This proton exhibits strong intramolecular hydrogen bonds with the other two nitrogen atoms. The methyl groups are directed away f.om the ring cavity. The bond distance between acid proton and an amine nitrogen in compound 2 is extremely short. The bond angles f.r 1 and 2 also exhibit obvious diversity inside of.triazacyclononae.

关键词： f.rmation crystal structure protonation triazacyclononane

Prevalence and Risk f.ctors of.Peripheral Artery Disease in a Group of.Apparently Healthy Young Cameroonians: A Cross-Sectional Study

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World Journal of.Cardiovascular Diseases 2018年第2期8卷 111-122页

作者： f.licité Kamdem Yacouba Njankouo Mapoure ba Hamadou f.nny Souksouna Ahmadou Musa Jingi Caroline Kenmegne f.rnando Kemta Lekpa Jaf. f.nkeu Kweban Gisèlei Mandy Jean Pierre Nda Mef.’o Henry Luma Marie Solange Doualla Internal Medicine Service Douala General Hospital Douala Cameroon f.culty of.Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon f.culty of.Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroon Chemical Pathology Laboratory Douala General Hospital Douala Cameroon

background: The?burden of.peripheral artery disease (PAD) is not well known among apparently healthy people in Af.ica. Aim: To determine the prevalence and associated risk f.ctors of.PAD in a group of.blood donors seen at the Douala General Hospital—Cameroon. Methods: Between 1st November 2015 and 30th April 2016, we carried out a cross-sectional study. Participants were consenting adults of.both sexes, aged ≥ 21 years who presented f.r blood donation, and were tested HIV negative. We collected socio-demographic data and their past history. We carried out a physical examination and measured their Ankle-Brachial Index (ABI). We def.ned PAD as an ABI Results: We recruited 103 participants, 55.4% males. The mean age was 33 ± 10 years. The mean ABI on lef. and right leg was 1.04 ± 0.1 and 1.02 ± 0.1respectively. ABI was higher in males than f.males both legs (p 0.05). PAD was seen in 11 (10.7%) participants. This was higher in f.males than males (3.6% versus 19.2%, p = 0.026). Among those with PAD, 8 (72.7%) were asymptomatic (Males: 100% versus f.males: 66%, p = 0.9). Af.er adjusting f.r age and gender, sedentary lif.style (aOR: 7.14, [95% CI: 1.38 - 33.3], p = 0.019), and f.male gender (aOR: 6.2, [95% CI: 1.26 - 30.5], p = 0.025) were signif.cantly associated with PAD. Conclusion: The prevalence of.PAD was high in this group of.HIV negative blood donors, most of.whom were asymptomatic. This was associated with f.males, and a sedentary lif.style.

关键词： Peripheral Artery Disease ABI Prevalence Risk f.ctors Douala

Making Biological Materials

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Journal of.Bionic Engineering 2005年第4期2卷 209-237页

作者： Julian f.V.Vincent Centre f.r Biomimetics and Natural Technologies Department of Mechanical Engineering The University of Bath Bath BA2 7AY UK

1 Chemistry and synthesis 1.1 Production and control of.materials These days there can be f.w people who do not know that proteins are def.ned by DNA. DNA is made of.two strands, each of.which has along it, like a string of.f.iry lights, side branches that meet between the strands and hold them together. It is the sequence of.these paired side branches （bases） that stores the inf.rmation needed to def.ne a protein. Three of.the bases in sequence provide the inf.rmation which, translated by the cell＇ s machinery, codes f.r a particular amino acid. Amino acids polymerise to make up specif.c proteins and, eventually, us. In def.ning an organism, that can weigh several tons, in its sequence of.bases, the minute amount of.DNA necessary f.r this task is an amazing example of.data compression. When I was at school in Cambridge, shortly af.er Crick and Watson had worked out the basic structure of.DNA f.r their Nobel prize, an enterprising breakf.st cereal company had a cardboard cut-out DNA double spiral on the back of.their packets. No doubt if.you ate enough breakf.sts you could save up f.r a whole gene. I don＇ t know what bit of.protein the DNA coded f.r - I suspect no one did at the time. I remember another of.the big names in genetics, Sydney Brenner （whose son went to our school and who later also got a Nobel prize）,

关键词： Making Biological Materials

基于注意力机制和深度学习模型的外来海洋生物命名实体识别

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大连海洋大学学报 2021年第3期36卷 503-509页

作者：贺琳张雨巴韩飞大连海事大学航运经济与管理学院辽宁大连116026

为解决因外来海洋生物领域实体复杂且实体间存在嵌套导致命名实体识别效果较差等问题,提出基于融合注意力机制的卷积神经网络(CNN)-双向门控循环单元网络(BiGRU)-条件随机场(CRf.网络模型进行外来海洋生物命名实体识别,并构造词向量、... 详细信息

为解决因外来海洋生物领域实体复杂且实体间存在嵌套导致命名实体识别效果较差等问题,提出基于融合注意力机制的卷积神经网络(CNN)-双向门控循环单元网络(BiGRU)-条件随机场(CRf.网络模型进行外来海洋生物命名实体识别,并构造词向量、词性特征向量等特征作为网络模型的联合输入,以提升网络模型识别效果。结果表明:使用融合多特征向量的CNN-BiGRU-CRf.络模型对外来海洋生物名称实体、时间实体、地名实体3类实体上的命名实体识别结果平均准确率达到了90.62%,平均召回率达到了89.50%,平均f.值达到了90.05%,较传统命名实体识别方法均有较大提高。研究表明,本研究中提出的网络模型可以充分提取文本特征,解决了文本的长距离依赖问题,对外来海洋生物领域的命名实体识别具有较好的识别效果。

关键词：海洋生物命名实体识别卷积神经网络深度学习

Variational Calculations of.Energies of.the (2snl) 1,3Lπand (2pnl) 1,3 LπDoubly Excited States in Two-Electron Systems Applying the Screening Constant per Unit Nuclear Charge

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Journal of.Modern Physics 2021年第3期12卷 328-352页

作者： Momar Talla Gning Ibrahima Sakho Maurice f.ye Malick Sow babou Diop Jean Kouhissoré badiane Diouldé ba Abdourahmane Diallo Department of.Physics Chemistry UFR Sciences and Technologies University of Thies Thies Senegal Department of.Physics Faculty of Sciences and Techniques University Cheikh Anta Diop of Dakar Dakar Senegal Department of.Physics UFR Sciences and Technologies University Assane Seck of Ziguinchor Ziguinchor Senegal

In this paper, resonance energies and excitation energies of.doubly 2sns 1,3Se, 2snp 1,3P0, 2pnp 1,3De, 2pnd 1,3f. and 2pnf.1,3Ge excited states of.the helium isoelectronic sequence with Z ≤ 10 are calculated. Calcul... 详细信息

In this paper, resonance energies and excitation energies of.doubly 2sns 1,3Se, 2snp 1,3P0, 2pnp 1,3De, 2pnd 1,3f./em>0 and 2pnf./em> 1,3Ge excited states of.the helium isoelectronic sequence with Z ≤ 10 are calculated. Calculations are carried out in the f.amework of.the variational procedure of.the f.rmalism of.the Screening Constant per Unit Nuclear Charge (SCUNC). New correlated wave f.nction of.Hylleraas type is used. Precise resonance and excitation energies are tabulated and good agreement is obtained when a comparison is made with available literature values.

关键词： Doubly Excited States Helium Isoelectronic Sequence Screening Constant per Unit Nuclear Charge (SCUNC) Correlated Wave f.nction Resonance Energy Excitation Energies

民用飞机后缘增升装置气动力特性SCCH试验研究

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复旦学报（自然科学版） 2017年第5期56卷 551-556页

作者：巴玉龙郭传亮中国商用飞机有限责任公司上海飞机设计研究院上海201210

针对民用飞机增升装置对机翼气动力特性的影响,在南京航空航天大学的NH-2低速风洞开展了某型号客机等弦长后掠半模增升装置测力风洞试验研究.试验来流马赫数为0.2,基于机翼气动弦长的试验雷诺数为1.85×106.通过试验结果,重点分析了后... 详细信息

针对民用飞机增升装置对机翼气动力特性的影响,在南京航空航天大学的NH-2低速风洞开展了某型号客机等弦长后掠半模增升装置测力风洞试验研究.试验来流马赫数为0.2,基于机翼气动弦长的试验雷诺数为1.85×106.通过试验结果,重点分析了后缘襟翼偏角、缝道宽度及缝道搭接量对机翼增升装置增升效率的影响,得到了襟翼偏角和缝道的最佳组合参数.研究结果表明:襟翼偏角和缝道宽度是影响机翼气动力特性的主要参数,缝道搭接量的影响较小;合适的缝道宽度能带来较大的升力系数和升阻特性,襟翼缝道宽度为2%时升力特性最佳,襟翼缝道宽度为1%时升阻比较大.

关键词：民用飞机增升装置后缘襟翼风洞试验升力系数

关于k-Hessian方程C2＋α局部解的存在性

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数学物理学报（A辑） 2017年第3期37卷 499-509页

作者：巴娜田范基郑列湖北工业大学理学院武汉430068 湖北大学数学与统计学学院应用数学湖北省重点实验室武汉430062

该文克服椭圆型k-Hessian算子的线性化算子不满足极大值原理的困难,利用NashMoser迭代,证明当非齐次项f.C~α变号或非负时,k-Hessian方程C^(2+α)局部解的存在性,当然当f.C~∞时,存在C~∞局部解.其技巧是首先证明线性化方程解的唯一性... 详细信息

该文克服椭圆型k-Hessian算子的线性化算子不满足极大值原理的困难,利用NashMoser迭代,证明当非齐次项f.C~α变号或非负时,k-Hessian方程C^(2+α)局部解的存在性,当然当f.C~∞时,存在C~∞局部解.其技巧是首先证明线性化方程解的唯一性,以此为基础得到线性化方程解的存在性,进而得到线性化方程解的高阶正则性和先验估计.

关键词： k-Hessian方程局部解 Nash-Moser迭代.