呼吸病区碳青霉烯耐药鲍曼不动杆菌的分子流行病学分析

目的研究呼吸病区碳青霉烯耐药鲍曼不动杆菌耐药机制及分子流行病学,为控制碳青霉烯耐药鲍曼不动杆菌的院内传播提供依据。方法呼吸病区19株非同一患者、1株医护人员手和3株病房围帘,共23株碳青霉烯耐药鲍曼不动杆菌用Phoenix100微生物鉴定系统进行菌种鉴定和药敏,用随机引物多态性DNA(RAPD)分型,脉冲场凝胶电泳(PFGE)进行同源性分析,PCR方法检测IMP、OXA、VIM、TEM耐药基因型以及Ⅰ、Ⅱ类整合子。结果23株碳青霉烯耐药鲍曼不动杆菌对亚胺培南(IPM)和美罗培南(MEM)耐药,对黏菌素敏感率为100%中除1株病人来源株以外,其余22株对10种抗菌药物均具有相同药敏谱,脉冲场凝胶电也显示该22株为同一组。碳青霉烯类耐药鲍曼不动杆菌携带TEMβ内酰胺酶、OXA-23苯唑西林酶、Ⅰ类整合酶阳性率分别为95.7%、69.5%及82.6%。结论碳青霉烯类耐药鲍曼不动杆菌耐药机制复杂,呼吸病区医院感染爆发可能与医护人员手卫生和病房围帘相关,应采取有效的院内感染预防与控制措施。

Tupu methods of spatial-temporal pattern on land use change:a case study in the Yellow River Delta

Comprehensive study on land-use change of spatial pattern and temporal process is the key component in LUCC study nowadays. Based on the theories and methods of Geo-information Tupu (Carto-methodology in Geo-information, CMGI), integration of spatial pattern and temporal processes of land-use change in the Yellow River Delta (YRD) are studied in the paper, which is supported by ERDAS and ARC/INFO software. The main contents include: (1) concept models of Tupu by spatial-temporal integration on land-use change, whose Tupu unit is synthesized by "Spatial·Attribute·Process" features and composed of relatively homogeneous geographical unit and temporal unit; (2) data sources and handling process, where four stages of spatial features in 1956, 1984, 1991, and 1996 are acquired; (3) integration of series of temporal-spatial Tupu, reconstruction series of "Arising" Tupu, spatial-temporal Process Tupu and the spatial temporal Pattern Tupu on land-use change by remap tables; (4) Pattern Tupu analysis on land-use change in YRD during 1956-1996; and (5) spatial difference of the Pattern Tupu analysis by dynamic Tupu units. The various landform units and seven sub-deltas generated by the Yellow River since 1855 are different. The Tupu analysis on land-use in the paper is a promising try on the comprehensive research of "spatial pattern of dynamic process" and "temporal process of spatial pattern" in LUCC research. The Tupu methodology would be a powerful and efficient tool on integrated studies of spatial pattern and temporal process in Geo-science.

基于遗传算法和等效电路模型的窄带通频率选择表面光窗设计方法

提出了一种窄带通频率选择光窗的快速设计方法,该方法结合遗传算法和等效电路模型,能快速准确地给出特定设计目标下光窗的结构参数。该光窗由石英玻璃及镀制在玻璃上下表面的亚波长的金属网栅构成。利用上述方法,可以在几十秒内直接优化出光窗在特定设计目标下的结构参数。与全波仿真相比较,正入射下等效电路模型的准确度高于93%。利用上述方法对光窗的结构参数进行优化,实现了通带透过系数损失小于1.5dB、带外抑制大于20dB、品质因子高于26的性能,同时光窗保持一定的可见光透过率且具有极化不敏感性。结果表明,该方法能快速有效地设计窄带通频率选择光窗。