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2009甲型h1N1流感住院患儿多中心临床研究

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中华儿科杂志 2010年第10期48卷 733-738页

作者： 2009甲型h1N1流感临床病例调查协作组 2009甲型h1N1流感临床病例调查协作组

目的了解2009年全国多中心2009甲型h1N1流感住院患儿的临床特征,探讨危重症的高危因素和死亡原因.方法对2009年秋冬季全国17家医院的810例2009甲型h1N1流感住院患儿的临床表现、实验室检查结果以及治疗和转归进行回顾性总结和分析.结... 详细信息

目的了解2009年全国多中心2009甲型h1N1流感住院患儿的临床特征,探讨危重症的高危因素和死亡原因.方法对2009年秋冬季全国17家医院的810例2009甲型h1N1流感住院患儿的临床表现、实验室检查结果以及治疗和转归进行回顾性总结和分析.结果 810例住院患儿中,男508例,女302例,年龄中位数为43个月,其中＜5岁550例（67.9%）,合并基础疾病148例（18.5%）.常见的表现及例数为：发热780例（96.3%）,流涕294例（36.3%）,鼻塞192例（23.7%）,咽痛147例（18.1%）,咳嗽759例（93.7%）,咯痰347例（42.8%）,喘息219例（27.0%）,呼吸困难163例（20.1%）,呕吐130例（16.0%）,腹泻66例（8.1%）,烦躁79例（9.8%）,嗜睡64例（7.9%）,惊厥32例（4.0%）.常见的实验室异常为：外周血白细胞计数增高或降低377例（46.5%）,乳酸脱氢酶增高346例（42.7%）,C反应蛋白增高306例（37.8%）,天冬氨酸转氨酶增高257例（31.7%）,肌酸激酶增高174例（21.5%）.586例（72.3%）合并肺炎,49例（6.0%）合并脑炎/脑病,30例（3.7%）合并心肌炎.危重症患儿183例,其基础疾病、外周血白细胞计数增高、中性粒细胞比率增高、淋巴细胞比率降低和C反应蛋白增高的发生率明显高于非危重症患儿.19例死亡,占危重患儿的10.4%,8例死于脑炎/脑病,10例主要死于严重肺炎和急性呼吸窘迫综合征,其中5例同时伴有脑炎/脑病,1例死于继发性真菌性脑膜炎.结论 2009甲型h1N1流感容易引起全身多脏器损害.有基础疾病、外周血白细胞计数增高、中性粒细胞比率增高、淋巴细胞比率降低和C反应蛋白增高可能是发生危重症病例的高危因素.合并严重肺炎和急性呼吸窘迫综合征,以及脑炎/脑病是导致死亡的主要因素.

关键词：流感,人流感病毒A型,h1N1亚型危重病儿童

化学气相沉积与渗透过程中热解炭织态结构生成机理研究(英文)

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新型炭材料 2006年第2期21卷 185-192页

作者：张伟刚 K.J. httinger 中国科学院过程工程研究所多相反应国家重点实验室北京100080 卡尔斯鲁厄大学化学技术研究所

为研究热解炭织态结构的生成规律,采用不同压强的甲烷为碳源,在1 100℃条件下进行了化学气相沉积和化学气相渗透实验。化学气相沉积以具有不同表面积/自由体积比([A/V]值)的直通方形多孔陶瓷为基体;化学气相渗透实验在直径为1mm细直孔... 详细信息

为研究热解炭织态结构的生成规律,采用不同压强的甲烷为碳源,在1 100℃条件下进行了化学气相沉积和化学气相渗透实验。化学气相沉积以具有不同表面积/自由体积比([A/V]值)的直通方形多孔陶瓷为基体;化学气相渗透实验在直径为1mm细直孔内表面沉积和对炭纤维体积分数为7%的炭毡进行致密化。借助正交偏光显微镜(消光角)和透射电子显微镜(定向角)对在不同实验条件下制备的热解炭进行分析和定量表征。研究发现:热解炭的织态结构可以在两种不同的沉积条件下形成。当甲烷压强较低时为化学生长阶段;当甲烷压强较高时为物理形核阶段。在化学生长控制阶段,热解炭的织态结构可以利用之前提出的“颗粒填充模型(P-F模型)”加以解释。该模型假设高织构热解炭的沉积一定对应于气相中存在具有合适比例的芳香化合物(例如苯)和线性小分子(主要是C2h2),当二者的浓度比偏离该最优比(或者偏大,或者偏小),均将导致中织构甚至低织构热解炭的生成。在化学生成控制阶段,化学气相沉积和化学气相渗透对热解炭织态结构影响的差别,除了[A/V]值而外,还有氢气的作用。在化学气相渗透过程中,基体内部生成的氢气快速扩散至基体表面,使内外沉积速率和织态结构均发生较大变化。

关键词：热解炭化学气相沉积化学气相渗透织态结构

Effects of rotation and magnetic field on the nonlinear peristaltic flow of a second-order fluid in an asymmetric channel through a porous medium

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Chinese Physics B 2013年第7期22卷 303-313页

作者： A. M. Abd-Alla S. M. Abo-Dahab h. D. El-Shahrany Department of Mathematics Faculty of ScienceTaif University Department of Mathematics Faculty of Science Department of Mathematics Faculty of ScienceSouth Valley University

In this paper, the effects of both rotation and magnetic field of the peristaltic transport of a second-order fluid through a porous medium in a channel are studied analytically and computed numerically. The material is represented by the constitutive equations for a second-order fluid. Closed-form solutions under the consideration of long wavelength and low Reynolds number is presented. The analytical expressions for the pressure gradient, pressure rise, friction force, stream function, shear stress, and velocity are obtained in the physical domain. The effects of the non-dimensional wave amplitude, porosity, magnetic field, rotation, and the dimensionless time-mean flow in the wave frame are analyzed theoretically and computed numerically. Numerical results are given and illustrated graphically in each case considered. Comparison was made with the results obtained in the presence and absence of rotation, magnetic field, and porosity. The results indicate that the effects of the non-dimensional wave amplitude, porosity, magnetic field, rotation, and the dimensionless time-mean flow are very pronounced in the phenomena.

关键词： peristaltic flow second-order fluid magnetic field porous medium

Oxidation of propane to acrylic acid and acetic acid over alkaline earth-doped Mo-V-Sb-O_x catalysts

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Journal of Natural gas Chemistry 2010年第6期19卷 593-599页

作者： Chandan S.Chaudhari Shailesh S.Sable hanumant Gurav Ashutosh A.Kelkar Vilas h.Rane Chemical Engineering and Process Development Division National Chemical Laboratory Catalysis Division National Chemical Laboratory

Alkaline earth metal （Mg,Ca,Sr and ba）-doped Mo-V-Sb-O x catalysts,prepared by a dry-up method,have been investigated for their catalytic performance in the oxidation of propane under different reaction *** catalysts have been characterized by N2 adsorption-desorption,temperature-programmed desorption （TPD） of Nh3,SEM and *** of water vapor on the catalytic performance,particularly on the selectivities to acetic acid and acrylic acid,has also been *** selectivity to acrylic acid was improved significantly by the doping of alkaline earth metals to Mo-V-Sb-O x *** surface acidic sites of the catalyst decreased with the doping of the catalyst with alkaline earth metals,which ultimately was found to be beneficial for obtaining high selectivity to acrylic *** catalytic activity and product selectivities were found to be influenced by the reaction temperature,C3h8/O2 ratio and space velocity.A significant improvement in the selectivity to acrylic acid has also been observed by the addition of water vapor in the feed of propane and oxygen in the oxidation of propane.

关键词： oxidation of propane surface acidity alkaline earth doped Mo-V-Sb-Ox catalysts acrylic acid acetic acid

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基于多源遥感数据的黄河数字流域模型改进

水利学报 2023年第8期54卷 930-941页

作者：薛源覃超吴保生张玍李丹傅旭东清华大学水圈科学与水利工程全国重点实验室北京100084 清华大学水利部水圈科学重点实验室北京100084 清华大学水利水电工程系北京100084 中国煤炭科工集团有限公司煤炭科学研究总院有限公司应急科学研究院北京100013

山区河流水系众多,往往因地势险要难以现场量测获得河流基础信息,是典型的缺资料地区。本文结合多源遥感提取的68个河流断面及34个水文站实测断面,建立了黄河中游各级别河流的断面概化模型。融合传统线状DEM水系及河流表面、概化断面构... 详细信息

山区河流水系众多,往往因地势险要难以现场量测获得河流基础信息,是典型的缺资料地区。本文结合多源遥感提取的68个河流断面及34个水文站实测断面,建立了黄河中游各级别河流的断面概化模型。融合传统线状DEM水系及河流表面、概化断面构建河道边界形态。针对黄河数字流域模型,基于不同级别河流的河道边界条件建立了断面判别模块,改进其汇流模型。以黄河一级支流皇甫川流域为例,以2010—2015年的资料率定模型,以2016年汛期日径流及年内3场典型洪水过程验证模拟效果。结果表明,改进后的模型输入参数均可由遥感观测获取,且日流量模拟的纳什效率系数高于0.8,流速及水深的模拟误差分别为7%、9%,全时期洪峰流量的模拟误差平均为15%、峰现时间误差约1.4 h,均较改进前明显提升。研究成果可为山区河流水文过程模拟及河流地貌演化等研究提供重要的基础数据和技术参考。

关键词：山区河流多源遥感河流断面黄河数字流域模型

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Monitoring long-term shoreline dynamics and human activities in the hangzhou bay,China,combining daytime and nighttime EO data

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Big Earth Data 2020年第3期4卷 242-264页

作者： Lixia Chu Francis Oloo Martin Sudmanns Dirk Tiede Daniel hölbling Thomas Blaschke Iulian Teleoacac aInterfaculty Department of Geoinformatics Z_GISUniversity of SalzburgSalzburgAustria hydrology and Earth Observation Lab The Technical University of KenyaNairobiKenya Department of Geography West University of TimişoaraTimişoaraRomania

Shorelines are vulnerable to anthropogenic activities including urbanization,land reclamation and sediment *** changes may be a reflection of the degradation of coastal ecosystems because of human *** the shoreline dynamics is,therefore,a topic of global *** observation data,such as multi-temporal satellite images,are an important resource for assessing changes in coastal *** this research,we used Google Earth Engine(GEE)to monitor and map historical shoreline dynamics in the hangzhou bay in China where the Qiantang River flows into the East China ***,we aimed to capture and quantify both the spatial and temporal shoreline changes and to assess the link between anthropogenic activities and shoreline changes on the integrity of this coastal *** implemented a Tasselled Cap analysis(TCA)on Landsat imagery from 1985 to 2018 in GEE to calculate the wetness *** then applied Otsu method for automatic image thresholding on the wetness coefficient to detect waterbodies and shoreline ***,we adopted the nighttime light data from the Defense Meteorological Satellite Program’s Operational Linescan System(DMSP-OLS)from 1992 to 2013 as a proxy of human *** results show that in the hotspot areas,the shoreline has moved by more than 5 km in the last decades,accounting for approximately 900 km^(2) of land *** this area,the human activity,indicated by the intensity of nighttime light,increased *** results of this work reveal the influence of human activities on the shoreline dynamics and can support policies that promote the sustainable use and conservation of coastal *** methodology can be transferred and applied to other coastal zones in various regions and scaled up to larger areas.

关键词： Shorelines dynamics human activities Google Earth Engine Earth observation

Comprehensive Transcriptome Analysis of Auxin Responses in Arabidopsis

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Molecular Plant 2008年第2期1卷 321-337页

作者： Ivan A. Paponov Martina Paponovt William Teale Margit Menges Sohini Chakrabortee James A.h. Murray Klaus Palme Faculty of Biology University of Freiburg Schanzlestrasse 1 79104 Freiburg Germany Institute of Biotechnology University of Cambridge Cambridge CB2 1QT United Kingdom

In plants, the hormone auxin shapes gene expression to regulate growth and development. Despite the detailed characterization of auxin-inducible genes, a comprehensive overview of the temporal and spatial dynamics of auxinregulated gene expression is lacking. here, we analyze transcriptome data from many publicly available Arabidopsis profiling experiments and assess tissue-specific gene expression both in response to auxin concentration and exposure time and in relation to other plant growth regulators. Our analysis shows that the primary response to auxin over a wide range of auxin application conditions and in specific tissues comprises almost exclusively the up-regulation of genes and iden- tifies the most robust auxin marker genes. Tissue-specific auxin responses correlate with differential expression of Aux/ IAA genes and the subsequent regulation of context- and sequence-specific patterns of gene expression. Changes in transcript levels were consistent with a distinct sequence of conjugation, increased transport capacity and down-regulation of biosynthesis in the temperance of high cellular auxin concentrations. Our data show that auxin regulates genes associated with the biosynthesis, catabolism and signaling pathways of other phytohormones. We present a transcriptional overview of the auxin response. Specific interactions between auxin and other phytohormones are highlighted, particularly the regulation of their metabolism. Our analysis provides a roadmap for auxin-dependent processes that underpins the concept of an ＇auxin code＇-a tissue-specific fingerprint of gene expression that initiates specific developmental processes.

关键词： Comprehensive Transcriptome Analysis Auxin Responses Arabidopsis

The efficacy and effectiveness of machine learning for weaning in mechanically ventilated patients at the intensive care unit: a systematic review

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Bio-Design and Manufacturing 2019年第1期2卷 31-40页

作者： Man Ting Kwong Glen Wright Colopy Anika M.Weber Ari Ercole Jeroen h.M.Bergmann Department of Engineering Science University of OxfordParks Road. Oxford OXI 3PJ. UK snap40 Inc.125 Princess Street Edinburgh EH2 4AD UK CRUK/MRC Oxford Institute for Radiation Oncology.Roosevelt Drive Oxford OX3 7DQ. UK Division of Anaesthesia Addenbrooke's Hospital University of Cambridge Hills Road Cambridge CB2 0QQ. UK

Weani ng from mechanical ventilation in the in tensive care unit (ICU) is a complex clinical problem and relevant for future organ engineering. Prolonged mechanical ventilation (MV) leads to a range of medical complications that increases length of stay and costs as well as contributes to morbidity and even mortality and long-term quality of life. The need to reduce MV is both clinical and economical. Artificial intelligence or machine learning (ML) methods are promising opportunities to positively influence patient outcomes. ML methods have been proposed to enhance clinical decisions processes by using the large amount of digital information generated in the ICU setting. There is a particular interest in empirical methods (such as ML) to improve management of "difficult-to-wean" patients, due to the associated costs and adverse events associated with this population. A systematic literature search was performed using the OVID, IEEEXplore, PubMed, and Web of Science databases. All publications that included (1) the application of ML to weaning from MV in the ICU and (2) a clinical outcome measurement were reviewed. A checklist to assess the study quality of medical ML publications was modified to suit the critical assessment of ML in MV weaning literature. The systematic search identified nine studies that used ML for weaning management from MV in critical care. The weaning management application areas included (1) prediction of successful spontaneous breathing trials (SBTs),(2) prediction of successful extubation,(3) prediction of arterial blood gases, and (4) ventilator setting and oxygenation-adjustment advisory systems. Seven of the nine studies scored seven out of eight on the quality index. The remaining two of the nine studies scored one out of eight on the quality index. This scoring may, in part, be explained by the publications' focus on technical novelty, and therefore focusing on issues most important to a technical audience, instead of issues most impor

关键词： Artificial intelligence Patient-centred medicine Clinical trial Critical care Data science

A continental back-arc setting for the Namaqua belt:Evidence from the Kakamas Domain

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Geoscience Frontiers 2022年第4期13卷 193-221页

作者： P.h.Macey R.J.Thomas A.F.M.Kisters J.F.A.Diener M.Angombe S.Doggart C.A.Groenewald C.W.Lambert J.A.Miller h.Minnaar h.Smith h.F.G.Moen E.Muvangua A.Nguno G.Shifotoka J.Indongo D.Frei C.Spencer P.le Roux R.A.Armstrong C.Tinguely Council for Geoscience P.O.Box 572BellvilleSouth Africa Department of Geology University of StellenboschSouth Africa Department of Geological Sciences University of Cape TownSouth Africa Geological Survey of Namibia WindhoekNamibia Department of Geology University of Free StateSouth Africa Department of Earth Sciences University of the Western CapeSouth Africa The Institute of Geoscience Research Dept.Applied GeologyCurtin UniversityPerthAustralia Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonCanada Geochronology and Tracers Facility British Geological SurveyNottingham NG125GGUK RSES Australian NationalUniversityCanberraACTAustralia

A study of the NW Kakamas Domain in South Africa/Namibia provides a new,unified lithostratigraphy and evolutionary history applicable to the whole Namaqua *** Mesoproterozoic history ranges from~1350 Ma to 960 Ma,but isotopic evidence suggests it was built upon pre-existing Paleoproterozoic continental crust that extended west from the Archaean *** eastern Namaqualand,early rift-related magmatism and sedimentation at~1350 Ma occurred in a confined ocean *** tectonic reversal and subduction at~1290–1240 Ma led to establishment of the Areachap,Konkiep and Kaaien *** the Kakamas Domain,widespread deposition of pelitic sediments occurred at~1220 Ma(Narries Group).These contain detrital zircons derived from proximal crust with ages between~2020 Ma and 1800 Ma(western Palaeoproterozoic domains)and 1350–1240 Ma(eastern early Namaqua domains),suggesting pre-sedimentation *** pelites underwent granulite grade metamorphism at~1210 Ma(peak conditions:4.5–6 kbar and 770–850°C),associated with voluminous,predominantly S-type granitoid orthogneisses between~1210 Ma and 1190 Ma(Eendoorn and ham River Suites)and low-angle ductile(D_(2))deformation which continued until~1110 Ma,interspersed with periods of *** enduring P-T regime is inconsistent with the expected crustal over-thickening associated with the generally-accepted collision-accretion Namaqualand ***,we propose the Namaqua Sector is a‘hot orogen’developed in a wide continental back-arc with subduction west of the present-day *** observed high geotherm resulted from thinned back-arc lithosphere accompanied by an influx of mantle-derived *** D_(2)deformation resulted from"bottom-driven"tectonics and viscous drag within the crust by convective flow in the underlying asthenospheric *** extended tectonothermal regime ceased at~1110 Ma when SW-directed thrusting stacked the Namaqua Domains into their current positions,constrained in

关键词： Kakamas Namaqua Geodynamics Geochronology hot orogeny Mesoproterozoic