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Predictors of Bacterial Meningitis among Paediatric Patients Aged 0 - 5 Years at Kenyatta Hospital, Kenya

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Open Journal of Pediatrics 2018年第3期8卷 207-220页

作者： june J. Serem Margaret Chege Dorcas Maina College of Health Sciences School of Nursing Sciences University of Nairobi Nairobi Kenya

Introduction: Meningitis remains a common and serious problem in children worldwide. One million instances of meningitis are assessed to happen in children worldwide each year. In Africa, where outbreaks are common 70% of meningitis cases are diagnosed in children under the age of five (5) years. Though in most cases, doctors diagnose early and adequate treatment started, 5% to 10% of patients still succumb during the 24 - 48 hours after onset of clinical features. In 2009, the mortality rate in Africa was four thousand deaths. Study Objective: This study describes the predictors of bacterial meningitis among children aged 0 - 5 years admitted at Kenyatta National Hospital (K.N.H.) paediatric wards. Methodology: The study adopted a descriptive cross-sectional design. It was carried out in K.N.H. paediatric wards. Data were obtained from consenting parent or guardian and healthcare workers (nurses and registrars). Study participants were selected by convenient sam-pling method. A total of 104 study participants were included in the study sample. In-depth interviews of key informants were conducted on 7 health workers;5 nurses from the paediatric wards and paediatric emergency unit and 2 paediatric registrars. Ethical consideration included full disclosure to participants, confidentiality, security of health records and informed consent. Data were collected by use of researcher administered semi-structured ques-tionnaire and desk reviews of patients’ files were also used. Qualitative data from the interviews were audio-taped. Logistic regression analysis was used for data analysis. Quantitative data were cleaned, entered and analysed using Statistical Package for Social Sciences (SPSS) version 23. Results were displayed by utilization of tables, pie charts. Qualitative data were transcribed, grouped in themes and analysed manually. Study Results: The majority of the children (55.8%) were female. The highest percentage of the children (53.8%) was aged less than one yea

关键词： Meningitis Child Predictors Kenya

Cd_(1-x)Zn_xTe晶体退火条件的选择及Zn压对退火晶体质量的影响

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物理学报 2001年第12期50卷 2327-2334页

作者：李宇杰张晓娜介万奇西北工业大学凝固技术国家重点实验室西安710072

采用传统Bridgman方法和加入acceleratedcruciblerotationtechnique的Bridgman(缩写为ACRT B)方法生长的Cd1 -xZnxTe(x=0 .0 4)晶体中存在有点缺陷、位错、杂质和Te沉淀等缺陷 .为了减少甚至消除这些缺陷 ,必须将生长后的CdZnTe晶片在C... 详细信息

采用传统Bridgman方法和加入acceleratedcruciblerotationtechnique的Bridgman(缩写为ACRT B)方法生长的Cd1 -xZnxTe(x=0 .0 4)晶体中存在有点缺陷、位错、杂质和Te沉淀等缺陷 .为了减少甚至消除这些缺陷 ,必须将生长后的CdZnTe晶片在Cd气氛下退火 .从Cd -Te和Cd0 .96 Zn0 .0 4Te的P T相图出发 ,详细讨论了CdZnTe晶体的气固平衡条件 ,并以此为依据选择退火条件 ,对ACRT -B法生长的Cd0 .96 Zn0 .0 4Te晶体进行了退火实验研究 .实验结果表明 ,气氛中的Zn压在一定程度内高于平衡压力有利于晶体中多余Te向晶体表面扩散 ,即有利于消除Te沉淀 .但过高的Zn压会使晶体表面成分偏离原始的化学配比 .此时 ,晶体表面与气氛强烈的原子交换 ,将造成严重的表面损伤 ,形成一层结晶质量很差的表面层 .同时 ,Zn原子向晶内的扩散 ,抑制了退火过程中晶内杂质向晶体表面的扩散 .因此 ,在较低的Zn压下退火 (但仍处于气固平衡范围内 ) ,能排除晶内杂质 .通过仔细研究不同条件下退火后晶片的结晶质量和断面成分分布 ,可以认为CdZnTe晶体的退火可分为去沉淀相退火、去杂质退火和均匀化退火几种 ,最佳的退火工艺应是多步骤。

关键词： Cd1-xZnxTe 退火气-固平衡晶体锌压 Zn压质量 Ⅱ-Ⅵ红外半导体材料镉锌碲化合物晶体缺陷

Relationship of soil surface CO_2 flux with microbial biomass carbon in the karst areas of Southwest China

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Chinese Science Bulletin 1999年第S2期44卷 122-123页

作者： PIAO Hechun, HONG Yetang and YUAN Zhiyun State key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China State key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE production of C02 in the soil results from the oxidation of soil organic matter by heterotrophic microorganisms and by the respiration of plant roots. The release of C02 from the soil is a major flux in theglobal carbon cycle, which is largely fuelled by plant production. In this note, we investigated the release of C02from soils of the karst region. We measured the amount of soil microbial biomass carbon,soluble organic carbon in the soil, and the flux of C02 from the soil surface over a 1-year period. Thisnote is to examine the factors affecting the flux of C02 from the soil surface in an ecosystem with nutrientpoor soils and limited amounts of soil microbial biomass. This study was conducted from june 1997 through May 1998 on a hill side, located in the suburbs ofGuiyang City in Guizhou Province of China （latitude 26°30’N, longitude 106°39’E）. Situated 1

关键词： soil carbon dioxide karst areas.

Assessment of coral bleaching using symbiotic zooxanthellae density and satellite remote sensing data in the Nansha Islands,South China Sea

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Chinese Science Bulletin 2011年第10期56卷 1031-1037页

作者： LI Shu,YU KeFu,CHEN TianRan,SHI Qi & ZHANG HuiLing CAS key Laboratory of Marginal Sea Geology,South China Sea Institute of Oceanology,Chinese Academy of Sciences Guangzhou 510301,China CAS key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China

Coral bleaching,characterized by a significant loss of symbiotic zooxanthellae,is the primary cause of mass coral mortality and reef degradation throughout the *** characteristics,processes,and resistance of corals to bleaching varies significantly and is dependent on environmental *** documented a mass coral bleaching event in june 2007 at the Meiji and Zhubi Reefs,Nansha Islands (NS),South China Sea using ecological surveys and measurement of coral zooxanthellae density and sea surface temperatures (SST).More than 35 species of corals (between 0-20 m in depth) were *** bleached corals accounted for 15.6% of total corals in the investigated *** branching corals Pocillopora and Acropora were the most vulnerable species whereas the massive corals Porites and Favia were more tolerant of the high ***,we found no evidence of bleaching in Agariciidae corals suggesting that this family is resistant to thermal *** bleached corals had lost 72%-90% of their symbiotic ***,corals that had no visual signs of bleaching had also lost 31%-53% of their zooxanthellae suggesting that most corals were experiencing the early stage of *** monthly mean SST during june 2007 was 30.8°C,the highest since *** on measurements of SST and the Hotspots and DHW data (NOAA),we conclude that it the extremely high SSTs triggered this coral bleaching *** results suggest that the previously accepted temperature thresholds used to predict coral bleaching based on satellite data are likely to underestimate the extent and intensity of coral bleaching,at least in the NS.

关键词：珊瑚礁南沙群岛中国南海卫星遥感数据漂白黄藻密度共生

Nutrient concentrations and fluxes in the Changjiang Estuary during summer

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Acta Oceanologica Sinica 2010年第2期29卷 107-119页

作者： CHEN Hongtao YU Zhigang YAO Qingzheng MI Tiezhu LIU Pengxia key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of China Qingdao 266100 China key Laboratory of Marine Environment Science and Ecology of Ministry of Education Ocean University of China Qingdao 266100 China

In june 2003 and 2006 concentrations of nutrient were determined in the Changjiang Estuary. The data indicated that phosphate and nitrate did not behave conservatively in the estuary, but silicate behaved conservatively. An important mobilization of phosphate and nitrate was observed from the river up to halfway in the estuary. Both input flux （from river to estuary） and output flux （from estuary to coastal zone） of phosphate, silicate and nitrate were calculated from statistical interpretations of the salinity profiles. There was a large discrepancy between input and output fluxes of phosphate and nitrate. The river fluxes of silicate, phosphate and nitrate （fr） are augmented 5.3%, 28.9% and 36.6% in june 2003 and 1.0%, 62.5%, 31.7% in june 2006 by internal inputs （fi）.The phosphate and nitrate fluxes are enhanced through the estuarine process, while silicate flux is unaltered. The authors present some long-term data for nutrient concentrations and the ratios of silicon to nitrogen to phosphorus in the Changjiang Estuary. Silicate level falled in the last two decades, while concentration of nitrate increased. Phosphate concentration had no significant change.

关键词： nutrients, estuarine environment distribution behaviour, transport, China,Changjiang Estuary

无溶剂条件下LiNTf_2催化的醛和酮的非手性硅氰化反应研究

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有机化学 2012年第5期32卷 934-938页

作者：王宏社曾君娥宝鸡文理学院化学化工系、陕西省植物化学重点实验室宝鸡721013

以LiNTf2为催化剂,在无溶剂条件下,醛或酮与三甲基氰硅烷(TMSCN)室温发生加成反应,得到相应的α-氰基硅醚.该法操作简便、反应条件温和、收率高、催化剂易回收和可以重复使用.

关键词： LiNTf2 醛酮硅氰化反应无溶剂

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“双循环”新发展格局中河北的策略

保定学院学报 2022年第3期35卷 13-19页

作者：张雪刘俊娥沧州师范学院教育学院河北沧州061001 沧州师范学院马克思主义学院河北沧州061001

在构建“双循环”新发展格局中,河北既有产业基础优势,也面临居民收入和消费水平较低、部分产业链供应链存在断点堵点、关键核心技术自主研发能力不强等问题和挑战。河北立足本省实际,精准施策,在扩大内需、提升河北供给体系与国内需求... 详细信息

在构建“双循环”新发展格局中,河北既有产业基础优势,也面临居民收入和消费水平较低、部分产业链供应链存在断点堵点、关键核心技术自主研发能力不强等问题和挑战。河北立足本省实际,精准施策,在扩大内需、提升河北供给体系与国内需求适配性、实现数字经济全产业链发展、构建科技创新多元模式、实现高水平对外开放、提高河北软实力上下足功夫,为构建新发展格局作出河北贡献。

关键词：河北新发展格局精准施策京津冀协同发展

Taxonomic diversity of fish assemblages in the Changjiang Estuary and its adjacent waters

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Acta Oceanologica Sinica 2010年第2期29卷 70-80页

作者： SHAN Xiujuan JIN Xianshi YUAN Wei key Laboratory for Sustainable Utilization of Marine Fisheries Resource of Ministry of Agriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 266071 China key Laboratory for Fishery Resources and Eco-environment of Shandong Province Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 266071 China

Taxonomic diversity of fish assemblages in the Changjiang Estuary （Yangtze River Estuary） and its adjacent waters was analyzed based on bottom trawl surveys carried out by R/V Beidou in june, August and October 2006. Four groups of fishes were identified for each survey by the twoway indicator species analysis （TWIA）. Taxonomic distinctness, species richness and phylogenetic diversity were used to detect changes in taxonomic structure of fish assemblages. Most dominant fish species mainly belonged to Perciformes, Pleuronectiformes, Clupeiformes, Scorpaeniformes and Tetraodontiformes. Species richness in offshore waters of the survey area was higher than that in the other area. The average taxonomic distinctness value （AvTD,△^＋） of each fish assemblage was close to the average taxonomic distinctness of master list in the Changjiang Estuary （79.9）, and had a positive correlation with species richness and Shannon diversity index （H′）. A negative correlation was found between variations in taxonomic distinctness （VarTD, A^＋） and traditional diversity indices, which were caused by fish species component that led to longer average path lengths among species. Taxonomic diversity index （△） had the similar results with species richness, Ht, Simpson diversity index （D） and Pielou＇s evenness index （J′）. VarTD also kept stable, which further certificated that fish assemblages and ecological environment were in equilibrium. Taxonomic distinctness index （△^＋） was relatively stable in most of fish assemblages, and had higher values in some fish assemblages for a few absolutely dominant species. The present study showed that fish community formed new equilibrium stability in 2006 in the Changjiang Estuary when compared with those in the corresponding months of annual survey from 1985 to 1986. And AvTD in each sampling station was lower than AvTD of master list in the Changjiang Estuary, so some ecological niches were absent in each sampling stations from taxonomic or phylogenetic r

关键词： the Changjiang Estuary fish assemblage taxonomic diversity

Seasonal variation and sources of low molecular weight organic acids in precipitation in the rural area of Anshun

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Chinese Science Bulletin 2011年第10期56卷 1005-1010页

作者： ZHANG YanLin lee XinQing CAO Fang HUANG DaiKuan State key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China State key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Low molecular weight (LMW) organic acids are important and ubiquitous chemical constituents in the atmosphere.A comprehensive study of the chemical composition of precipitation was carried out from june 2007 to june 2008 at a rural site in Anshun,in the west of Guizhou Province,*** this period,118 rainwater samples were collected and the main LMW carboxylic acids were determined using ion *** average pH of rainwater was 4.89 which is a typical acidic *** most abundant carboxylic acids were formic acid (volume weight mean concentration:8.77 μmol L-1) and acetic acid (6.90 μmol L-1),followed by oxalic acid (2.05 μmol L-1).The seasonal variation of concentrations and wet deposition fluxes of organic acids indicated that direct vegetation emissions were the main sources of the organic *** concentrations were observed in winter and were ascribed to the low winter rainfall and the contribution of other air pollution sources northeast of the study *** ratio of formic and acetic acids in the precipitation ([F/A] T) was proposed as an indicator of pollution *** suggested that the pollution resulted from direct emissions from natural or anthropogenic *** with acid precipitation in other urban and rural areas in Guizhou showed that there was a decreasing contribution of LMW organic acids to free acidity and all anions in rainwater from urban to remote rural ***,it is necessary to control emissions of organic acids to reduce the frequency of acid rain,especially in rural and remote areas.

关键词：低分子量有机酸农村地区季节变化降水安顺平均浓度化学成分污染来源