Regional Consequences of Local Population Demography and Genetics in Relation to Habitat Management in Gentiana pneumonanthe

Abstract:  A joint demographic and population genetics stage-based model for a subdivided population was applied to Gentiana pneumonanthe , an early successional perennial herb, at a regional (metapopulation) scale. We used numerical simulations to determine the optimal frequency of habitat disturbance (sod cutting) and the intensity of gene flow among populations of G. pneumonanthe to manage both population viability and genetic diversity in this species. The simulations showed that even small populations that initially had near-equal allele frequencies could, if managed properly through sod cutting every 6 to 7 years, sustain their high genetic variation over the long run without gene flow. The more the allele frequencies in the small populations are skewed, however, the higher the probability that in the absence of gene flow, some alleles will be lost and within-population genetic variation will decrease even under proper management. This implies that although local population dynamics should be the major target for management, regional dynamics become important when habitat fragmentation and decreased population size lead to the loss of local genetic diversity. The recommended strategy to improve genetic composition of small populations is the introduction of seeds or seedlings of nonlocal origin.     

AGA法及其在非线性数学模型参数估计中的应用

介绍了在基因算法基础上改进的加速基因算法（ＡＧＡ），并通过环境非线性数学模型参数估计实例对该法与传统参数估计方法进行了比较。初步结果表明，ＡＧＡ法直观、简便、拟合精度高、通用性强，易为广大环境工程技术人员理解和使用。     

活性污泥法简化数学模型的研究与进展

介绍几种简化数学模型 (如ROM、SPM、SLM等 )的结构与特点。模型的验证结果表明 ,简化模型能够较好的模拟系统的运行 ,产生较为准确的模拟结果     

石家庄市大气主要污染物的统计预报

介绍了石家庄市在大气主要污染物预报统计模式方面的研究，包括统计回归分析的原理，预报选取的因子，主要污染物的回归方程及其相关系数和推广应用情况，通过分析指出了模式存在的不足，并给出了改进方向。     

生物膜填料床内废气净化的理论模型

介绍了废气生物净化技术的基本原理，并对废气生物净化技术中的生物过滤法和生物滴滤法的理论模型研究进展进行了综述，探讨了理有理论模型存在的主要问题。     

2017年7-8月国内生产安全事故统计分析

统计了2017年7-8月国内发生的各种生产安全事故117起,其中包括交通事故、矿业事故、爆炸事故、火灾、毒物泄漏与中毒和其他事故.统计表明,在117起事故中,交通事故占61.54％,矿业事故占4.27％,爆炸事故占5.13％,火灾占4.27％,毒物泄漏与中毒占8.55％,其他事故占16.24％.117起事故共死亡502人.死亡人数的百分比分别为交通事故65.94％,矿业事故4.78％,爆炸事故3.39％,火灾3.39％,毒物泄漏与中毒5.98％,其他事故16.53％.2017年7-8月生产安全事故发生较多的5个省和自治区分别为广东(10起)、内蒙古(8起)、云南(7起)、四川(7起)和山西(6起);死亡人数较多的5个省和自治区分别为广东(57人)、陕西(43人)、内蒙古(31人)、四川(29人)和云南(27人).     

Modeling Connectivity of Non‐floodplain Wetlands: Insights,Approaches, and Recommendations

Representing hydrologic connectivity of non‐floodplain wetlands (NFWs) to downstream waters in process‐based models is an emerging challenge relevant to many research, regulatory, and management activities. We review four case studies that utilize process‐based models developed to simulate NFW hydrology. Models range from a simple, lumped parameter model to a highly complex, fully distributed model. Across case studies, we highlight appropriate application of each model, emphasizing spatial scale, computational demands, process representation, and model limitations. We end with a synthesis of recommended “best modeling practices” to guide model application. These recommendations include: (1) clearly articulate modeling objectives, and revisit and adjust those objectives regularly; (2) develop a conceptualization of NFW connectivity using qualitative observations, empirical data, and process‐based modeling; (3) select a model to represent NFW connectivity by balancing both modeling objectives and available resources; (4) use innovative techniques and data sources to validate and calibrate NFW connectivity simulations; and (5) clearly articulate the limits of the resulting NFW connectivity representation. Our review and synthesis of these case studies highlights modeling approaches that incorporate NFW connectivity, demonstrates tradeoffs in model selection, and ultimately provides actionable guidance for future model application and development.     

最低气温对兰州市呼吸系统疾病就诊人次的影响研究

通过2013年1月1日~2017年7月31日兰州市呼吸系统疾病逐日就诊资料和气象资料,采用分布滞后非线性模型（DLNM）方法,分析0~30d滞后影响,研究极端低温对不同年龄（<15岁、16~45岁、46~60岁、>60岁）和性别人群呼吸系统疾病就诊人次的影响.结果发现：日均最低温度对相对危险度（RR）的最大RR变化范围为0.89~1.41,变化趋势整体呈现出V字型,在低温附近,温度越低,RR越高;滞后0~4d,极端低温代表的冷效应影响最为显著;滞后5~19d,在日均最低温度0℃附近,出现新的峰值,冷效应对RR的贡献有所下降,热效应对RR的贡献完全消失;滞后20~30d,日均最低温度为-10℃时,出现RR最小值,0℃温度点附近维持RR峰值;滞后22d时,滞后影响完全消失.在极端低温条件下,呼吸系统疾病对低龄人群表现出长期滞后性和高发性,对高龄人群表现出短期滞后性.男性比女性患病的滞后效应更长,患病风险更大.     

垃圾渗滤液与再生水生物毒性的体外检测方法应用

本文总结了近年来在垃圾渗滤液和再生水生物毒性检测方面的主要体外试验模型和检测方法,并整理了这些模型和方法在生物毒性评价中的应用.目前常用的体外试验模型包括人源细胞系、其他哺乳动物细胞以及微生物细胞,相比较而言,人源细胞系在检测结果外推至人体时具有更强的说服力,因而其应用最为广泛.体外检测方法可概括为细胞毒性、遗传毒性和内分泌干扰效应检测三个方面,其中内分泌干扰效应的研究较多集中于雌激素效应.最后,本文提出开发三维体外细胞模型、体外试验与化学分析相结合、全面分析内分泌干扰效应和建立成组体外试验体系是渗滤液和再生水生物毒性检测方法的发展方向.