Quercetin enhances and modulates the fungal killing efficacy of chicken heterophils through immunological recognition,effector functions,and resolution

Herbal compound, quercetin, has previously been shown its modulatory effects on mammalian neutrophils and avian counterpart. However, at this instance it is not clear how quercetin promotes its effects on fungal and yeast killing in chicken heterophils. In the present study, we have proved that quercetin exerts the significant modulatory effects against pathogenic yeast (Candida albicans) in freshly isolated heterophils from Thai native broiler chicken. This substance is shown to facilitate heterophil effector functions through the reduction of ROS generation, and promotion of phagocytosis and candidacidal killing. The quercetin effects on zymosan recognition and migration of cells toward zymosan are subtle, but insignificant differed from control, whereas cell migration towards live Candida is markedly differed. We also find the abundant release of heterophil extracellular traps (HETs) from quercetin-primed cells. From a gene expression standpoint, cells received quercetin display the up-regulation of fungal recognition and migratory genes. The quercetin shows anti-inflammatory function by suppression of pro-inflammatory cytokine genes as well as most of ROS-related genes. Collectively, our findings highlight and provide clues for a promising utilization of quercetin in chicken innate immunity to further combat the fungal infections.     

森林生态系统涡度相关法碳通量长时间连续性缺失数据插补方法的比较

针对森林通量观测站涡度相关法碳通量观测普遍存在的长时间连续性数据缺失情景,为探究不同数据插补方法的有效性,以华北低丘山地栓皮栎人工混交林生态系统为例,以经EddyPro处理和质量控制的2017年3月1日-11月30日0.5h尺度净生态系统碳交换（NEE）数据为基准数据集,随机生成含有连续1、3、7、15和31d数据缺失的5类数据缺失集,重复10次,使用固定窗口平均昼夜变化法（MDV）、可变窗口平均昼夜变化法（MDC）、查表法（LUT）、非线性回归法（NLR）、边际分布采样法（MDS）、人工神经网络法（ANN）对缺失数据集进行插补,并将插补数据与实际观测数据进行对比,通过分析统计参数来评估不同方法的插补精度和稳定性,以评估不同方法的适用范围。结果表明：日间,当连续缺失少于15d时,ANN方法插补数据与实测数据间的R2（决定系数）相对较高,NLR方法的R2较低;LUT方法插补数据与实测数据间的相对均方根误差（RRMSE）较低,NLR方法的RRMSE较高。当缺失达到连续15d时,除NLR方法的R2显著较低（P＜0.05）外,其它方法间R2差异不显著;LUT方法的RRMSE显著（P＜0.05）较低,其它方法间RRMSE差异不显著。当缺失达到连续31d时,除NLR方法R2显著较低（P＜0.05）外,各方法间R2和RRMSE无显著差异;MDV方法的平均绝对误差（MAE）出现较多异常值,各方法间的MAE开始出现分化的趋势。随着缺失片段长度的增加,除MDV方法外,各方法的R2呈下降趋势,连续1d缺失与连续31d缺失情景下插补所得NEE与实测NEE的R2差异显著（P＜0.05）;MDV和MDS方法的RRMSE呈增大趋势,连续1d缺失与连续31d缺失情景下的RRMSE差异显著（P＜0.05）,其它方法的RRMSE差异相对不显著。夜间,在各缺失情景下,ANN方法的R2较高,LUT方法的R2较低,二者之间差异显著（P＜0.05）;LUT方法的RRMSE最高,与其它方法存在显著差异（P＜0.05）。在连续缺失大于31d的情景下,各方法的RRMSE差异均不显著。除LUT方法MAE显著（P＜0.05）较高外,其它方法的MAE无明显差异。随着缺失片段长度的增加,MDC、MDS和ANN方法插补数据的R2呈下降趋势,MDV和LUT的R2始终无显著差异;各方法的RRMSE差异无显著变化。在对典型晴天0.5h尺度上NEE日变化趋势的还原方面,MDC方法性能相对较优。综上,NLR方法适用于气象数据完备、NEE数据连续缺失少于7d的情景;MDV或MDC方法适用于气象数据不可用或缺失严重、NEE数据连续缺失少于15d的情景;LUT和MDS方法则适用于气象数据缺失较少、NEE数据连续缺失少于15d的情景;ANN方法适用性相对较广,可用于气象数据缺失较少、NEE数据连续缺失长达31d的情景。     

鲤科鱼肠道菌分布及共生关系研究

对草鱼、青鱼、白鲢、鳙鱼、团头鲂、三角鲂、鲤鱼和鲫鱼等4个亚科鱼肠道菌群中的好氧菌或兼性厌氧菌进行了分离鉴定，并对菌群种类和分布进行了X^2和相关分析，给出了一种测度菌群在寄主中广泛分布的广谱系数。结果发现同一亚科的鱼内菌群分布有极高的相似性。而不同亚科的鱼间菌群分布有较大的差异，但雅罗鱼亚科（Leuciscinae)和鳊亚科（Abramidnae)在菌群分布也有极显著的正相关性。哈夫尼亚菌属、致病杆菌属、气单胞菌属、柠檬酸菌属、假单胞菌属在这8种鱼中有较高的广谱系数（9．8937－19．0177）且其x^2测验不显著：而链球菌属、拉思氏菌属、芽孢杆菌属和葡萄球菌属的广谱系数很低。在0．54－2．3922之间各自只在1种或2种亚科中能检测到，因此是属于专一性共生菌。     

山西杂谷螟虫分布区划及综合治理技术研究

山西省不同生态区亚洲玉米螟和粟灰螟的地理分布规律受寄主作物、海拔高度和无霜期的影响。海拔１５００ｍ，无霜期１００天以下的内长城以北的高寒山区，为不发生区；海拔１０００～１５００ｍ以上，无霜期１２０天左右的地区，为１代发生区；地处北纬３８．５°～３６°的平川盆地，无霜期１５０天左右，为１～２代和２代发生区；北纬３６°以南的大部分地区，海拔较低，无霜期较长，一年两作区，为２～３代发生为害区；３代发生区极少，一般在北纬３６°以南地区。防治对策是：抓好大同、晋中、晋南盆地玉米螟的防治和忻定、吕梁山区、上党盆地粟灰螟的防治。防治措施以化学防治为主，辅之以农业和生物防治。     

青南高原高寒草甸四种嵩草种群分布格局初探

运用序列样方法,调查了四种嵩草枝条密度,通过方差:均值t 检验法、x~2值检验法和森下(Morisita)捐数Ⅰ_Δ判别法初步得出:高山嵩草分布格局为随机的群聚型;线叶嵩草、别氏嵩草和矮嵩草分布格局都属于非随机的群聚型。高山嵩草没有发现群聚斑块存在,其余三种嵩草有二个群聚斑块存在。并计算了各级样方内两两种的相关系数。     

离散大系统的一致渐近ξ——稳定性

对离散大系统采用分解和K类函数方法,研究了系统中关于部分变元的稳定性。得到了三个一致渐近ξ——稳定的充分条件。     

Historical Change on Distribution and Quantity of the South-China Tiger (Panthera tigris amoyensis)

DistributionandQuantityofwildSouth-ChinatigerDistributionTheSouth-ChinatigersonlydistributeinChinaandtheskullstruCtureappeartobethemostsimilarwiththoseoftheirancestors.Asoneoffivesurvivedtigersubspecies,thistigersubspecieshasthelestquantityandisthemostendangeredintheworld.Therefore,the"InternationalTigerConservationStrategy"ScientificWorkshop,whichheldinMinnesotaoftheUnitedStatesofAmericaintheearlyof1986,pointedoutthattheSouth--Chinatigerwasoneofthemostendangeredanimalspecieswhichneede…     

Wetland vegetation distribution modelling for the identification of constraining environmental variables

Wetland ecosystems are of primary concern for nature conservation and restoration. Adequate conservation and restoration strategies emerge from a scientific comprehension of wetland properties and processes. Hereby, the understanding of plant species and vegetation patterns in relation to environmental gradients is an important issue. The modelling approaches in this study statistically relate vegetation patterns to measured environmental gradients in a lowland wetland ecosystem. Measured environmental gradients included groundwater quantity and quality aspects, soil properties and vegetation management. Among this variety, the objective was to identify the key environmental gradients constraining the vegetation, using recently developed methodologies within the modelling approaches. Comparison of results indicated that different environmental gradients were considered to be important by different methodologies.     

城市绿地防灾避难功能评价指标体系研究

我国城市绿地经过多年的发展,已具有一定的系统和规模.目前,关于城市绿地系统的研究已不鲜见,但城市绿地防灾避难功能的研究才刚刚起步.现探讨城市绿地防灾避难功能评价指标体系,希望给城市防灾减灾体系建设提供规划和决策参考.