硫酸化香菇多糖对新城疫疫苗免疫效果的影响

试验Ⅰ:免疫应答试验:取450只雏鸡随机均分为9组,在14日龄用新城疫Ⅳ系疫苗免疫,同时分别肌肉注射高、低剂量的3种硫酸化香菇多糖(sLNT_1、sLNT_2、sLNT_3)和香菇多糖(LNT)。分别于首免前和首免后连续6周检测血清HI抗体效价和外周血T淋巴细胞增殖的动态变化。试验Ⅱ:免疫保护试验:取350只雏鸡随机均分为7组,除非免疫组外其余组用新城疫Ⅳ系疫苗免疫,同时3个sLNT组和LNT组分别注射sLNT_1、sLNT_2、sLNT_3和LNT。于免疫后第21天,除无佐剂对照组第2组外各组鸡均肌肉注射NDV强毒攻毒,观察保护效果,并分别于攻毒前和攻毒后第3、6、9、12和15天测定血清HI抗体效价和外周血T淋巴细胞增殖的动态变化。结果表明:3种sLNT在首免后28 d内比LNT显著提高血清抗体效价最高2个滴度(高剂量的效果优于低剂量),促进淋巴细胞增殖(低剂量的效果强于高剂量);攻毒鸡发病率和死亡率降低,保护率提高最多达17.5%,加速攻毒后血清抗体生成和T淋巴细胞增殖,病鸡最快可以在攻毒后6 d恢复正常。综合评价以sLNT_2的效果最好。揭示:硫酸化修饰能显著提高LNT的免疫增强活性,增强新城疫疫苗的...     

水处理生物膜载体研究进展

生物膜载体是生物膜工艺的核心部分,载体的选择适当与否直接影响到废水的处理效果。概述了废水处理用生物膜载体的现状与发展,重点介绍了有机合成高分子生物膜载体在亲水性、生物亲和性和磁性等方面的改性研究,壳聚糖、藻酸盐和纤维素等可降解材料作为生物膜载体在废水处理中的应用研究。针对当今生物膜载体应用带来的二次污染问题,提出了解决办法和发展方向,指出可降解生物膜载体的应用可有效避免废弃生物膜载体处理带来的二次污染,是生物膜载体研究的一个重要发展方向。参32     

Development of an automated climatic data scraping, filtering and display system

One of the many challenges facing scientists who conduct simulation and analysis of biological systems is the ability to dynamically access spatially referenced climatic, soil and cropland data. Over the past several years, we have developed an Integrated Agricultural Information and Management System (iAIMS), which consists of foundation class climatic, soil and cropland databases. These databases serve as a foundation to develop applications that address different aspects of cropping systems performance and management. In this paper we present the processes and approaches involved in the development of a climatic data system designed to automatically fetch data from different web sources, consolidate the data into a centralized database, and delivery the data through a web-based interface.Climatic data are usually available via web pages or FTP sites. The exact steps to scrape data from different sources vary depending on how the data are rendered. The climatic data building process presented herein is broken down into 5 major program modules, corresponding to different phases of the process: Data Requester, Data Fetcher, Data Parser, Data Filter, and Data Explorer. The Data Requester is responsible for processing the web pages that lead to the determination of the requested weather data. The Data Fetcher is responsible for fetching weather data that is made available by the data sources based on the request from the Data Requester. The Data Parser is responsible for decompressing and parsing the contents of the original data file and saving the data to an SQL Server 2005 database. The Data Filter is responsible for data quality control and for estimating missing data and saving the filtered data. The Data Explorer is designed to provide web-based user access to the consolidated and filtered climatic data using both dropdown lists and map-based navigation.Three types of data are stored in the process: original climatic data in file format, parsed climatic data in SQL Server database, and filtered climatic data in SQL Server database. The resulting consolidated and filtered climatic database provides a common foundation that allows us to develop diversified applications that require dynamic access to near real-time data. A number of applications have been and are being developed that seamlessly access the foundation class climatic database. Collectively these applications address water conservation, crop production and management, land use suitability analysis, and bioenergy refinery site selection.     

2009年版《英国药典》介绍

简要介绍了2009年版《英国药典》的编排体例及主要内容,包括凡例、收载品种、制剂通则、附录,以及英国兽药典等。     

Comparative analysis of three chemometric techniques for the spectroradiometric assessment of canopy chlorophyll content in winter wheat

Hyperspectral data sets contain useful information for characterizing vegetation canopies not previously available from multi-spectral data sources. However, to make full use of the information content one has to find ways for coping with the strong multi-collinearity in the data. The redundancy directly results from the fact that only a few variables effectively control the vegetation signature. This low dimensionality strongly contrasts with the often more than 100 spectral channels provided by modern spectroradiometers and through imaging spectroscopy. With this study we evaluated three different chemometric techniques specifically designed to deal with redundant (and small) data sets. In addition, a widely used 2-band vegetation index was chosen (NDVI) as a baseline approach. A multi-site and multi-date field campaign was conducted to acquire the necessary reference observations. On small subplots the total canopy chlorophyll content was measured and the corresponding canopy signature (450-2500 nm) was recorded (n_obs = 42). Using this data set we investigated the predictive power and noise sensitivity of stepwise multiple linear regression (SMLR) and two ‘full spectrum’ methods: principal component regression (PCR) and partial least squares regression (PLSR). The NDVI was fitted to the canopy chlorophyll content using an exponential relation. For all techniques, a jackknife approach was used to obtain cross-validated statistics. The PLSR clearly outperformed all other techniques. PLSR gave a cross-validated RMSE of 51 mg m⁻² for canopy chlorophyll contents ranging between 38 and 475 mg m⁻² (0.99 ≤ LAI ≤ 8.74 m² m⁻²). The lowest accuracy was achieved using PCR (RMSE_cv = 82 mg m⁻² and ). The NDVI, even using chlorophyll optimized band settings, could not reach the accuracy of PLSR. Regarding the sensitivity to artificially created (white) noise, PCR showed some advantages, whereas SMLR was the most sensitive chemometric technique. For relatively small, highly multi-collinear data sets the use of partial least square regression is recommended. PLSR makes full use of the rich spectral information while being relatively insensitive to sensor noise. PLSR provides a regression model where the entire spectral information is taken - in a weighted form - into account. This method seems therefore much better adapted to deal with potentially confounding factors compared to any 2-band vegetation index which can only avoid the most harmful factor of variation.     

果园气象因子远程监测系统的设计与开发

应用LabVIEW虚拟仪器开发平台,结合数据采集卡和各种传感器,实现了果园气象因子参数的实时采集、显示和存储,并利用LabVIEW自带的远程面板技术让客户远程监控服务器端。结果表明：统能较好地实现果园生态环境远程实时监测,为果树生产管理提供及时准确的园区信息。     

基于基态修正时空模型的行政区划图更新方法研究

随着地理信息系统在我国日常生活中的广泛应用,数据不易获取的问题越发突出,特别是行政区划图这种变更频繁、标准制图周期长的数据。根据我国行政编码的规范和行政区划变更特点,在基态修正模型的基础上采用面向对象的方式组织空间数据,通过对行政区划变更事件的记录,生成新的行政区划图,并在此基础上实现空间数据的管理和回溯查询,解决了空间数据需求的现势性问题。     

冬季典型灰霾天气过程的特征分析

利用辽宁中部地区2008年1月的气象与环境监测资料,对该地区发生的一次灰霾天气过程进行了分析。结果表明,由于冬季地面、高空稳定的天气条件,特别是地面500m以下的城市边界层区域的大气扩散能力的较弱,造成了空气中污染物不能扩散,导致环境空气质量恶化,颗粒物浓度增高,能见度下降,形成灰霾过程。     

基于PDA的农产品市场数据采集系统

以PDA为硬件平台,采用C/S架构,对GSM、蓝牙、GPRS、合并复制等技术进行了集成应用,设计、开发了基于PDA的农产品市场数据采集系统,该系统有利于提高工作效率、实现信息发布的及时性,具有一定的实用价值。     

数据挖掘技术在农业信息数据资源研究上的应用

简述了数据挖掘的定义、方法,介绍了农业数据的价值传递性、专业性、时空二维性特点,以及数据挖掘技术在农业上的应用现状。