Inter- and intra-genomic heterogeneity of the intervening sequence in the 23S ribosomal RNA gene of Campylobacter jejuni and Campylobacter coli

An intervening sequence (IVS) can be present or absent in the 23S rRNA of Campylobacter jejuni and Campylobacter coli. As part of a survey, we used a polymerase chain reaction (PCR) assay to detect the presence of the IVS in 43 isolates of C. coli and 82 isolates of C. jejuni. An IVS was present in 40 (93.0%) of the C. coli and only 34 (41.5%) of the C. jejuni isolates. Twelve (27.9%) of the C. coli isolates and seven (8.5%) of the C. jejuni isolates resulted in two polymerase chain reaction products, indicating heterogeneity in the presence of the 23S rRNA IVS. Fourteen of the isolates with two products were evaluated by pulse-field gel electrophoresis; 13 different patterns were observed. The total band size of one isolate was substantially greater than the expected 1.7 Mb, possibly indicating a mixed culture. Southern blot analyses demonstrated the expected three rRNA operons in all tested isolates. Nested PCR reactions with operon-specific primers followed by primers for the IVS confirmed that the strains of interest contained either one or two operons carrying the IVS and the remaining operon(s) did not. Sequence analysis of the IVS and flanking regions of the 23S rRNA genes did not discriminate C. jejuni and C. coli as distinct populations. These results indicate horizontal transfer of 23S rRNA genes or portions of the genes between C. jejuni and C. coli. Also, data showing sequence polymorphisms between the three 23S rRNA loci outside of the IVS region suggest that the isolates with intra-genomic heterogeneity appear to be members of clones that have an ancient defect in gene conversion mechanisms needed for concerted evolution of the ribosomal operons.     

Television's Interpellation: Heeding, Missing, Ignoring, and Resisting the Call for Pan-National Identity in the Brazilian Amazon

ABSTRACT   In this article, I focus on the ways in which audiences in the Amazonian community of Gurupá respond to television's interpellation for pan-national identity. I examine how viewers heed, miss, ignore, and resist the call for identity as well as how their various responses to this "call" shape their worldview and behavior and impact the process of nation building. Utilizing audience ethnography over a 25-year period, I show in this study how televisual messages are contextualized and localized, mitigating the forces of nationalistic homogenization.     

Improving neural network prediction of effluent from biological wastewater treatment plant of industrial park using fuzzy learning approach

Three types of adaptive network-based fuzzy inference system (ANFIS) in which the online monitoring parameters served as the input variable were employed to predict suspended solids (SS_eff), chemical oxygen demand (COD_eff), and pH_eff in the effluent from a biological wastewater treatment plant in industrial park. Artificial neural network (ANN) was also used for comparison. The results indicated that ANFIS statistically outperforms ANN in terms of effluent prediction. When predicting, the minimum mean absolute percentage errors of 2.90, 2.54 and 0.36% for SS_eff, COD_eff and pH_eff could be achieved using ANFIS. The maximum values of correlation coefficient for SS_eff, COD_eff, and pH_eff were 0.97, 0.95, and 0.98, respectively. The minimum mean square errors of 0.21, 1.41 and 0.00, and the minimum root mean square errors of 0.46, 1.19 and 0.04 for SS_eff, COD_eff, and pH_eff could also be achieved.     

张家界国家森林公园土地利用格局变化

借助地理信息系统（GIS）技术对张家界国家森林公园1990～2000年土地利用格局变化进行了研究。结果表明：（1）1990～2000年问,张家界国家森林公园保护效果显著。近成过熟林面积基本稳定,1990年97．57％的阔叶近成过熟林、96．77％的马尾松近成过熟林和77．92％的杉木近成过熟林至2000年仍保存良好;未利用地恢复较好、灌木林保护较好,25．38％的未利用地、30％以上的灌木林分别转变为阔叶林、马尾松林或杉木林;中龄林、幼龄林保护较好,很大一部分中龄林、幼龄林分别转变为近成过熟林和中龄林。建议继续强化管理,落实《张家界国家森林公园森林经营方案》,避免重经济利益轻生态环境保护现象发生;（2）森林砍伐、农田侵占现象仍然存在。2000年,100％的马尾松幼龄林由1990年马尾松中龄林转变而来,74．06％杉木幼龄林由杉木近成过熟林转变而来,将近10％未利用地由阔叶近成过熟林或阔叶中龄林转变而来。2000年,11．19％居民点及道路与34．82％经济林均由农田转变而来。建议引导社区积极参与生态旅游,通过开展生态旅游切实提高农民收入,减小社区居民对森林公园的胁迫作用;同时注重耕地资源的保护。     

关于马尔萨斯(Malthus)增长定律的研究

利用马尔萨斯(Malthus)增长定律对生命科学、国民经济以及银行信贷等方面的问题进行了系统分析,刻画出其复杂的非线性动力特征,给出了马尔萨斯定律解决实际问题的方法．     

我国国家级自然保护区数量特征研究

研究我国国家级自然保护区数量特征对加强保护区建设和管理具有重要意义。本文通过资料收集,采用方差分析、多元比较、相关分析等数理统计方法,分析了我国国家级自然保护区数量和面积的分布格局、各类型保护区各功能区划面积比例及功能区面积与物种的关系等数量特征。结果表明,我国国家级自然保护区数量上以森林生态系统类型最多;面积上为荒漠生态系统类型最大;面积分布格局呈现从西向东及从北向南逐渐减少的趋势。方差分析表明不同类型国家级自然保护区3个功能区面积所占其总面积的比例之间差异不显著;相关分析表明在以物种为保护对象的保护区中,其总面积、各功能区面积与物种数量、动植物种类的相关性显著。该研究相关结果为我国自然保护区的建设与管理提供一定的参考依据。     

An interview with Olivia Gude about connecting school and community arts practice

ABSTRACT

Olivia Gude has a long and distinguished career as both a public artist and an art educator. She is currently the Angela Gregory Paterakis Professor and Chair of Art Education at the School of the Art Institute of Chicago (SAIC), where she works with graduate and undergraduate students to prepare for working as artist educators in school and community settings. Her scholarly work includes a number of articles and book chapters about art education and community art. Prof. Gude has worked as a community public artist for many years and has created over 30 large-scale mural and mosaic projects, working with intergenerational groups, teens, elders, and children. I interviewed Prof. Gude at the SAIC building in downtown Chicago to discuss how her school, university, and community art engagement as well as her work with the National Coalition for Core Arts Standards, might offer suggestions for transforming arts education for the twenty-first century and provide authentic connections between school and community. Prof. Gude discusses important enduring understandings and big ideas from the new Visual Arts National Core Arts Standards, the Spiral Workshop youth art and research project she created while at University of Illinois at Chicago, and how her experience as a community artist informs her work with students in classroom settings.     

基于GIS与多目标区位配置模型的沈阳市公园选址

结合地理信息系统(GIS)与多目标区位配置模型(LA),综合考虑4个相对独立的目标因子(人口密度等级、空气污染等级、城市热岛效应等级、土地利用格局)对沈阳市三环内城市公园进行优化选址,并将优化结果与公园现状空间分布进行比较,以评价城市公园空间布局的合理性.结果表明： 与其他因子相比,空气污染因子对研究区城市绿地的选址具有重要影响.与单目标因子相比,多目标综合加权分析的结果能够合理地为城市绿地提供优化的空间选址.GIS与LA相结合的方法为城市绿地的空间优化提供了新思路.