基于ZigBee无线传感器网络的灌溉控制系统设计

在采用一款ZigPyce解决方案的射频芯片CC2430和ZigBee协议栈的基础上,设计了一个简单的无线传感器网络灌溉控制系统,给出了相应设计方案和软件中的实现细节.该系统实现了对土壤含水率的实时检测,并依据土壤含水率灌溉阈值进行自动控制灌溉,以达到节水灌溉的目的.初步测试证明,该系统运行稳定可靠,能够准确获取网络节点...     

水泥窑配料控制系统设计

根据水泥厂配料要求,本文介绍了一种新型智能化数据采集和控制系统.该系统以STD5055 CPU板为核心,STD总线结构,用CRT显示,通过键盘可方便地修改石料和焦粉的配比.     

高校图书馆考试类图书采访质量控制

列举了高校图书馆考试类图书的主要种类,分析了影响考试类图书采访质量的原因,同时从实际工作出发,阐述了提高考试类图书采访质量的系列措施。     

蔬菜生长环境参数检测系统的研制

为了研究干旱对作物的影响，研制了基于MCS-51系列单片机的环境参数检测系统。系统可以实时采集蔬菜主要环境参数，进行数据存储、图谱分析和历史数据查询。试验结果表明，系统基本满足要求，且运行可靠。     

灌区多元化数据采集与监控系统方案设计

介绍了多元化的灌区数据采集与监控系统的总体方案设计及实现，重点讨论了数据采集内容、采集手段、数据传输方式和数据平台等问题，为“数字灌区”的具体实现提供参考。     

烟盲蝽传播云南烟草丛枝症病害研究

用生物学测定方法对烟盲蝽传播云南烟草丛枝症的规律进行了研究。结果表明，烟盲蝽能够传毒的最少头数为1头，传毒效能随带毒虫数量的增加而增加，单株虫量为1－3头时，传毒效能为50％，单株虫量为5－10头时，传毒效能为60％－80％，单株虫量达15头以上时，传毒效能达100％；烟盲蝽成虫或若虫能够获毒的最短取食时间为1h，在1－6h范围内，相同时间内的若虫获毒率高于成虫，获毒时间在6h以上时成虫与若虫的获毒率相同，达90％以上，获毒时间在12h以上时，获毒率达100％；烟盲蝽若虫传毒的最短取食时间为0．5h，成虫传毒的最短取食时间为1h；当取食时间超过最短时间时，传毒率随取食时间的增加而升高。若虫取食时间达12h以上，成虫取食时间达24h以上时，传毒率达100％。     

Intracranial,extraneural ectopic lymph node in a bovine (Bos taurus)

The brain from a field necropsied 8‐month‐old feedlot heifer presenting with an acute history of depression, lethargy, dyspnoea and anorexia was evaluated grossly and by histopathology. The meninges overlying the left cerebral hemisphere contained a 12 × 26 × 32 mm, dark red, soft, ovoid mass. Histologic examination of this tissue revealed a well‐organized lymph node with normal architecture. Organization of reactive lymphoid tissue resembling normal lymph node architecture may occur under chronic stimulation. However, there are no known aggregates of lymphoid tissue present within the cranial vault in any veterinary species. This is the first reported case of an intracranial ectopic lymph node in any species.     

基于无线传输的稻田灌溉监控系统

为实现稻田环境的监控和节水灌溉,该文设计了基于无线传输的稻田灌溉监控系统,其中包括1个主站和18个基站,采用日精ND250A数传电台进行无线数据通信。基站可按设定的时间间隔自动采集稻田水温、土壤湿度、稻田水位等参数,并当接到主站指令时通过无线传输将数据上传到主站;基站供电采用太阳能蓄电池,以满足传感器运行及无线通讯的能耗需求。PLC控制灌溉设备的运行,运用组态软件设计人机交互界面,可自动或手动进行灌溉操作;工控机可运行基于Web的信息管理系统,监控灌溉现场的运行情况并在显示器上动态显示各种实时操作。该系统运行稳定,能够实现准确的无线数据采集,适用于稻田灌溉的实时监控。     

The use of pestivirus antigen ELISA currently available for the detection of hairy shaker disease/border disease virus in sheep

AIMS: To estimate the number of cases of scrapie that would occur in sheep of different prion protein (PrP) genotypes if scrapie was to become established in New Zealand, and to compare the performance of two commercially available, rapid ELISA kits using ovine retro-pharyngeal lymph nodes (RLN) from non-infected and infected sheep of different PrP genotypes.

METHODS: Using published data on the distribution of PrP genotypes within the New Zealand sheep flock and the prevalence of cases of scrapie in these genotypes in the United Kingdom, the annual expected number of cases of scrapie per genotype was estimated, should scrapie become established in New Zealand, assuming a total population of 28 million sheep. A non-infected panel of RLN was collected from 737 sheep from New Zealand that had been culled, found in extremis or died. Brain stem samples were also collected from 131 of these sheep. A second panel of infected samples comprised 218 and 117 RLN from confirmed scrapie cases that had originated in Europe and the United States of America, respectively. All samples were screened using two commercial, rapid, transmissible spongiform encephalopathy ELISA kits: Bio-Rad TeSeE ELISA (ELISA-BR), and IDEXX HerdChek BSE-Scrapie AG Test (ELISA-ID).

RESULTS: If scrapie became established in New Zealand, an estimated 596 cases would occur per year; of these 234 (39%) and 271 (46%) would be in sheep carrying ARQ/ARQ and ARQ/VRQ PrP genotypes, respectively. For the non-infected samples from New Zealand the diagnostic specificity of both ELISA kits was 100%. When considering all infected samples, the diagnostic sensitivity was 70.4 (95% CI=65.3–75.3)% for ELISA-BR and 91.6 (95% CI=88.2–94.4)% for ELISA-ID. For the ARQ/ARQ genotype (n=195), sensitivity was 66.2% for ELISA-BR and 90.8% for ELISA-ID, and for the ARQ/VRQ genotype (n=107), sensitivity was 81.3% for ELISA-BR and 98.1% for ELISA-ID.

CONCLUSIONS: In this study, the ELISA-ID kit demonstrated a higher diagnostic sensitivity for detecting scrapie in samples of RLN from sheep carrying scrapie-susceptible PrP genotypes than the ELISA-BR kit at comparable diagnostic specificity.

CLINICAL RELEVANCE: The diagnostic performance of the ELISA-ID kit using ovine RLN merits the consideration of including this assay in the national scrapie surveillance programme in New Zealand.     

Effects of the Tillering Nodes on the Main Stem of a Chinese Large-Panicle-Type Rice Cultivar,Yangdao 4, on the Growth and Yield-Related Characteristics in Relation to Cropping Season

Abstract

Using a Chinese large-panicle-type high-yielding indica rice cultivar, Yangdao 4 (YD), pot experiments were carried out to determine the effects of the removal of the lower nodal primary tillers on the growth and yield-related characteristics in comparison with a Japanese cultivar, Hinohikari (HH), with almost the same growth duration. The plants with all tillers remaining (Cont), those with tillers from the 5th and higher nodes (T5) and those with tillers from the 8th and higher nodes (T8) were prepared by removing the other tillers and grown in early, normal and late cropping seasons, sowing in late April, May and June, respectively. The lowest nodal primary tillers in each group emerged earlier and the number of days from sowing to flag leaf expansion and to full heading stage was reduced in the late cropping season, especially in HH. The maximum number of stems and number of panicles were larger in HH than in YD, and tended to be higher in the order of Cont > T5 > T8 plants. The average panicle weight per stem was higher in YD than in HH and higher in the order T8 > T5 > Cont. Panicle weight per hill was higher in YD than in HH in each cropping season and higher in early cropping season in both cultivars. Panicle weight decreased with delayed tiller emergence in YD, but not in HH. Panicle weight was more closely related to straw weight in YD than in HH. Therefore, the promotion of vegetative growth by early sowing and development of lower nodal tillers is more effective for attaining a high yield in YD than in HH.