Survival Under Conditions of Environmental Stress: Variability of Brain Morphology and Behavior in the House Mouse

Two populations of laboratory mice lived outdoors in open pens for two years. Thereafter, some of them were bred in the laboratory. Morphometric analysis showed that the size of the synaptic projection area of mossy fibers (in the CA3 region of the hippocampus), which has an important functional role, and some behavioral traits of the open-pen mouse progeny had significant genetically determined differences from those in the initial population. This was attributed to differential breeding accounted for by the influence of severe environmental factors. Under environmental stress, selection occurred in the population and the mice with behavioral and neuromorphological characteristics differing from those of the control group proved to be better adapted to such conditions.     

C919飞机边线噪声级预测算法

为了新飞机试飞前能获得飞机边线噪声级,缩短新飞机噪声合格审定周期,对飞机边线有效感觉噪声级预测方法进行了研究,利用飞机相关物理参数及声压公式建立了完整的飞机边界噪声级预测算法。以波音、空客、CRJ系列飞机为例,验证该算法的有效性。控制飞机单一物理参数变化,分析各参数对飞机边线有效感觉边界噪声值的影响等级,提出降低飞机边线有效感觉噪声值的建议。将该算法应用于预测C919飞机边线噪声值,阐明了该算法在飞机噪声适航审定工作中的重要作用。     

湘江流域传统村落景观基因变异及其分异规律

传统村落在历史、文化、经济、旅游和科学等多个方面价值颇高,保护传统村落的空间格局和文化内涵极为重要。以中国湘江流域上中下游六个典型传统村落为例,以景观基因理论为基础,运用景观基因分析法识别了湘江流域传统村落景观基因,分析了上中下游传统村落显性物质景观基因与隐性非物质文化基因的变异特征,总结了湘江流域传统村落景观基因变异特征及分异规律,研究结果显示：（1）湘江流域上游传统村落平面基因变异相悖于本土的情况侧重发生在平面结构变异上;立面基因的变异相悖于本土、突变后直接消亡的情况较多;文化基因上受外来冲击的不适感较强,有加剧景观基因变异的风险和趋势。（2）湘江流域中游传统村落对立面基因的改动需求较大,且改动时间较早,造成立面基因变异以及平面基因中街巷格局、平面布局变异较大,变异后相悖于本土的特征显著;而在文化基因中,对文化的变异融合接受能力强,变异相融于本土的情况显著。（3）湘江流域下游传统村落在形态、布局特征明显的平面基因中产生的变异不大显著;在立面基因中遭遇突变后直接消亡的特征明显;在文化基因中,对家风信仰的基因变异以相融于本土为主,习俗礼仪的基因变异呈现分化趋势,单民族聚居式的家族以相悖于本土的特征为主,多民族聚居式的家族以相融于本土的特征为主。     

1种基于CCRP火灾情况下的动态疏散算法

为在火灾发生时给逃生人群规划最优的安全疏散方案,基于CCRP算法开发1种火灾情况下受容量限制的动态疏散算法。该算法模型将发生火灾的建筑布局信息表达成节点连接弧形式,鉴于可预测危害蔓延对火灾逃生过程中疏散通道封锁时间的影响,为建筑网络图上的节点赋予“危险时刻”属性,逃生人员通过节点的时刻必须小于该节点的“危险时刻”才能规避火灾危险;基于eclipse软件平台,通过动态疏散算法与相似Dinesh算法应用实例对比仿真分析,验证基于CCRP的动态疏散算法的可行性与优越性。结果表明:通过该算法计算出的逃生路径保证逃生人员在最短时间疏散出去;且其具有安全性高和耗时少等优点。     

Phenological mismatch and the effectiveness of assisted gene flow

The persistence of narrowly adapted species under climate change will depend on their ability to migrate apace with their historical climatic envelope or to adapt in place to maintain fitness. This second path to persistence can only occur if there is sufficient genetic variance for response to new selection regimes. Inadequate levels of genetic variation can be remedied through assisted gene flow (AGF), that is the intentional introduction of individuals genetically adapted to localities with historic climates similar to the current or future climate experienced by the resident population. However, the timing of reproduction is frequently adapted to local conditions. Phenological mismatch between residents and migrants can reduce resident × migrant mating frequencies, slowing the introgression of migrant alleles into the resident genetic background and impeding evolutionary rescue efforts. Focusing on plants, we devised a method to estimate the frequency of resident × migrant matings based on flowering schedules and applied it in an experiment that mimicked the first generation of an AGF program with Chamaecrista fasciculata, a prairie annual, under current and expected future temperature regimes. Phenological mismatch reduced the potential for resident × migrant matings by 40–90%, regardless of thermal treatment. The most successful migrant sires were the most resident like in their flowering time, further biasing the genetic admixture between resident and migrant populations. Other loci contributing to local adaptation—heat‐tolerance genes, for instance—may be in linkage disequilibrium with phenology when residents and migrants are combined into a single mating pool. Thus, introgression of potentially adaptive migrant alleles into the resident genetic background is slowed when selection acts against migrant phenology. Successful AGF programs may require sustained high immigration rates or preliminary breeding programs when phenologically matched migrant source populations are unavailable.     

HSY算法在水质模型参数识别中的应用探讨

参数识别是水质模拟中的技术核心，数据稀缺是水质模型经常面临的问题。采用HSY算法可求得模型参数的分布，而不再是一个单一的最优参数，从而在一定程度上避免了由于“最优”参数失真带来的决策风险，本文以南水北调一期工为例，讨论了在稀疏数据条件下如何应用HSY算法识别CSTR水质模型的参数，并对识别的模型参数进行了检验。模型检验采取了2种方法：分别用动态和稳态计算方法得出的参数进行比较；用模拟结果分布于实测值进行比较。结果表明，HSY算法为稀疏数据条件下进行识别、建立数学模型提供了一条有效的途径。     

B－P网络用于环境质量分类研究

用全国２５个湖泊的水质指标资料作为训练样本，应用人工神经网络Ｂ－Ｐ算法，分别建立了３参数和４参数的水质分类模型。并用所建立的模型对６个湖泊水质进行分类检验效果。结果表明Ｂ－Ｐ模型应用于环境质量分类是可行的。且由于Ｂ－Ｐ网络有自学习、自适应的能力，因而与其它的环境质量分类法相比具有优越性。     

富营养化评价的幂函数加和型普适指数公式

提出了一个用幂函数加和型表示湖泊富营养化评价的综合指数公式,并采用粒子群算法优化公式中的参数,得出优化后适用于多指标的富营养化综合评价的普适指数公式,该公式的特例也可作为单项指标的富营养化评价指数公式.将优化好的湖泊富营养化评价公式用于我国不同地域和不同类型的65个湖泊的实例评价.其评价结果与用修正卡森指数公式TSI.和我国营养状态指数公式TSI,及其它方法的评价结果基本一致,并与实况相符,从而为水体富营养化评价提供了一种新的有效途径.     

Synthesis of CuO nanoparticles through green route using Citrus limon juice and its application as nanosorbent for Cr(VI) remediation: Process optimization with RSM and ANN-GA based model

In present investigation, an attempt has been made for the synthesis of cupric oxide nanoparticles (CuONPs) through a green route by utilizing lemon juice extract as a bioreductant. The synthesized CuONPs were characterized through UV–visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The CuONPs were utilized for Cr(VI) removal from water through adsorption method in batch mode at different initial Cr(VI) concentration, pH, temperature and CuONPs dosage. The maximum uptake capacity of CuONPs was found to be 16.63 mg of Cr(VI)/g at pH 4.0. Implementation of response surface methodology (RSM) followed by artificial neural network hybridized with genetic algorithm (ANN-GA) approach has resulted maximum Cr(VI) adsorption of 98.8% under the optimized conditions of initial metal concentration 22.5 mg/L, pH 3.81, CuONPs dose 1.28 g/L and temperature 37.1 °C. Under optimum conditions, adsorption isotherm study was conducted, which showed that the fitness of experimental data was well achieved with Langmuir isotherm model illustrating monolayer pattern of adsorption. Thermodynamic study revealed that the process was spontaneous and endothermic in nature, while adsorption kinetics was best explained by pseudo-second order kinetic model.     

射线追踪中与地形的加速技术研究

在采用射线追踪方法的仿真软件中,一般都会判断射线与地形的交点,从而判断射线与哪块地形发生相交和反射、绕射。目前地形多采用三角面的形式来模拟。而一条射线对较大地形所有三角面进行一次相交的判定的过程较长。就射线与地形判断相交和确定交点的位置的过程中估计射线路径从而减少与三角面的相交判断从而进行加速,从而使得射线追踪时间能够大幅度的缩短,提高了软件仿真的效率。