四种杀虫剂对扶芳藤上稠李巢蛾的室内毒力测定

采用叶片浸渍法,利用4种杀虫剂对稠李巢蛾的进行室内毒力测定,以期筛选高效、低毒的有效药剂,指导在扶芳藤上的稠李巢蛾的防治。结果表明:药剂处理24和48h后的室内毒力结果基本相同,稠李巢蛾幼虫对供试药剂的敏感程度依次为:1.8%阿维菌素乳油200g/L氯虫苯甲酰胺悬浮剂氯40%毒死蜱乳油0.3%印楝素乳油,其对稠李巢蛾3龄幼虫24和48h的LC50分别为1.96、7.18、12.53、276.46mg/L和1.19、1.03、6.30、184.40mg/L。建议在生产上采用阿维菌素和氯虫苯甲酰胺防治稠李巢蛾。     

保加利亚主要鲜食葡萄品种评价

保加利亚位于巴尔干半岛的东南部．属于温带气候．北部略受大陆性气候影响,南部带有地中海气候特点．气候和土壤等自然条件非常适宜葡萄种植．是世界著名的葡萄与葡萄酒生产国之一。长期以来．保加利亚的农业科研机构非常注重鲜食葡萄品种的选育研究．     

乳粉中黄曲霉毒素M1的检测能力验证

设计并实施乳粉中黄曲霉毒素M1（aflatoxin M1,AFM1）的检测能力验证计划,了解和评价实验室检测乳粉中AFM1的检测能力和水平,识别实验室间存在的差异,促进实验室提高检测水平。参照CNAS—CL002《能力验证结果的统计处理和能力评价指南》制备分割水平对的样品,采用单因素方差分析和t检验对样品均匀性和稳定性进行分析。对能力验证结果进行稳健统计分析,通过Z值比分数评价实验室能力。结果表明：样品通过均匀性和稳定性的检验要求,满足能力验证计划要求;参加实验室49 家,满意结果数为45 家,满意率为9     

基于MEA-BP神经网络对木材内部缺陷诊断的研究

为了提高木材内部缺陷的自动识别率,采用电阻层析成像(ERT)的方法获取电导率波动信号,通过小波包变换对采集的数据进行3层小波包分析,对八维特征向量进行提取,利用思维进化算法(MEA)优化权值和阈值,孔洞、节子、腐朽试样各45组数据,进行BP神经网络训练,每种缺陷20组作为测试集,识别木材内部缺陷。结果表明:MEA-BP神经网络对木材孔洞、节子和腐朽的识别率分别为96.92%、95.38%和92.31%,该模型解决了复杂组合的优化问题,提高了搜索效率,并且达到最佳的预测效果。     

Simplified inference about dominance in forest stands

In a series of papers, Binkley and coauthors suggested dominance curves as a framework for understanding growth dominance and resource use efficiency in forest stands. Constructing a dominance curve requires three major supporting components: an appropriate allometric equation for biomass, sufficient data to characterize the size distribution of trees in the stand, and data on growth from a sufficient number of trees to characterize the relationship between tree size and growth across the entire size distribution. These components are not always available. Here, I propose a simplified approach to inference that can be used to diagnoze positive, neutral, and reverse dominance when the conditions for constructing a full dominance curve cannot be met. I illustrate the approach with published data from an old-growth kauri (Agathis australis) stand, which shows clear evidence of reverse dominance.     

联合浸提剂在我国测土施肥中的应用与发展

测土施肥是提高农作物产量、降低农业成本、节约资源、减少污染的重要举措,我国的土壤测试采用的是常规方法,耗时长、费力大、成本高,已经不适合目前我国高投入的农业生产水平,发达国家采用的联合浸提剂一次浸提可以用于十几个甚至几十个元素的测定,大大节省了操作步骤,实现了土壤测试的批量化、快速化。我国必须引进和发展一种速度快、价格低廉,适合我国的测试方法才能广泛应用于农业生产。该研究通过阐述我国化肥工业的现状以及国内外测土施肥的发展,总结了联合浸提剂在我国测土施肥中的应用与发展前景。     

Quantitative Analysis of Stress Echocardiograms in Healthy Horses with 2‐Dimensional (2D) Echocardiography,Anatomical M‐Mode,Tissue Doppler Imaging,and 2D Speckle Tracking

Background: Stress echocardiography is used to diagnose myocardial dysfunction in horses, but current methods are not well standardized. The influence of heart rate (HR) on measurements is largely unknown. Objectives: To investigate the use of 2‐dimensional echocardiography (2DE), anatomical M‐mode (AMM), tissue Doppler imaging (TDI), and 2D speckle tracking (2DST) at rest and after exercise for quantification of regional and global left‐ventricular (LV) function. Animals: Five athletic Warmblood horses; 11.6 ± 3.6 years; 529 ± 48 kg. Methods: Prospective study. Three separate echocardiographic examinations were performed before (baseline) and over 5 minutes after treadmill exercise with 2DE (1st, short‐axis view; 2nd, long‐axis view) and pulsed‐wave TDI (3rd examination). Offline analyses were performed at baseline and after exercise at HR 120, 110, 100, 90, and 80 minute^?1. Global and segmental measurements were compared by analysis of variance. Results: Quantitative analyses of stress echocardiograms were feasible in all horses. None of the AMM indices changed significantly after exercise. Stroke volume and ejection fraction by 2DE and strain by 2DST decreased, whereas strain rate by 2DST increased significantly at HR > 100 minute^?1. TDI analyses were technically difficult and provided little additional information. Conclusions and Clinical Importance: Volumetric indices by 2DE and strain and strain rate by 2DST are applicable for quantitative assessment of stress echocardiograms. In healthy horses, they are significantly altered at a HR > 100 minute^?1 and need to be evaluated in view of the instantaneous HR. Further investigations are needed to define the clinical value of stress echocardiography in horses with cardiac disease.     

蛋白芯片检测鸡猪组织中磺胺二甲基嘧啶等4种兽药的残留

应用蛋白芯片技术建立了动物组织（猪肉、猪肝和鸡肉、鸡肝）中重要兽药（盐酸克伦特罗、链霉素、恩诺沙星、磺胺二甲基嘧啶）的高通量筛选方法,并与酶联免疫吸附试验、气相色谱串联质谱、高效液相色谱和微生物检定法进行了比对。     

Toxoplasmosis Prevention and Testing in Pregnancy,Survey of Obstetrician–Gynaecologists

Toxoplasmosis in pregnant women can lead to congenital disease with severe neurological and ocular complications in the foetus. In 2006, we surveyed US obstetrician–gynaecologists to determine their knowledge and practices about toxoplasmosis prevention and testing. Questionnaires were mailed (four mailings) to a random sample of 1200 of the 33 354 members of the American College of Obstetricians and Gynecologists (ACOG). Of the 1200 surveyed, 502 (42%) responded. The respondents were similar to all ACOG members by gender, region of the country and practice type (P > 0.5), and age (respondents were slightly younger, mean 46 years versus 47 years). To prevent toxoplasmosis, most respondents indicated that they counsel pregnant women about cat litter (99.6%), but fewer counselled about eating undercooked meat (77.6%), handling raw meat (67.4%), gardening (65.4%) or washing fruits and vegetables (34.2%). Many (73.2%) respondents were not aware that some Toxoplasma IgM tests have had a high false positive rate, and most (91.2%) had not heard of the avidity test, which can help determine the timing of Toxoplasma gondii infection in relation to pregnancy. There is a need for more education about T. gondii serological testing, particularly the Toxoplasma avidity test. US obstetrician–gynaecologists are providing beneficial counselling to their patients, but could provide more information about undercooked meat and soil risks.     

干旱过程对耕地自然生产功能的影响

客观评估干旱过程对耕地自然生产功能的影响有利于耕地保护中的科学决策。该文评价了干旱过程对北京耕地自然生产功能的影响。首先利用地表湿润指数来表征地表干湿程度,经Mann-Kendall方法检验出1951－2006年北京典型的干旱过程;其次利用气象数据和桑斯维特纪念模型计算了干旱过程起始和中止年份的自然生产潜力;最后分析了干旱过程对耕地自然生产潜力的影响。主要结论如下：1951－2006年,北京总体呈变干趋势,1979－1984年和1998－2006年干旱过程比较明显;1979、1984、1998和2006年北京平均自然生产潜力分别约为1 043、912、1 085和872 g/(m2·a),其中通州区的单位自然生产潜力最大,延庆最小;干旱过程对耕地自然生产潜力影响较大,自然生产潜力总量减少量在1979－1984年超过了10%,到1998－2006年即将达到20%。因此,在耕地管理过程中,不仅要注重耕地的数量和分布,还要考虑气候波动尤其是干旱过程对耕地生产功能的影响。