A remote irrigation monitoring and control system (RIMCS) for continuous move systems. Part B: field testing and results

Precision irrigation systems can have inherent errors that affect the accuracy of variable water application rates controllers, as well as affect the controllers’ performance when evaluated on different continuous move irrigation systems configurations. The objective of this study was to assess the performance of a remote irrigation monitoring and control system (RIMCS) installed on two separate linear move (LM) irrigation systems. The RIMCS varies water application rates by pulsing nozzles controlled by solenoids connected via relays to a single board computer (SBC) with wireless Ethernet connection to a remote server. The system also monitors irrigation system flow, pressure, position and wireless field sensor networks. The system was installed on a LM irrigation system in Prosser, Washington, USA and on a LM in the Nesson Valley of North Dakota, USA. For the LM at Prosser, four pre-defined irrigation patterns were imposed and variable rates were applied as a percentage of the nozzle base application rate. Each nozzle was pulsed across the span length and along the LM travel direction. For the LM at the Nesson Valley, a quadratic pattern was imposed pulsing banks of nozzles along the LM travel direction. Standard catch can tests were performed and the system performance was evaluated by comparing measured catch can water depths with pre-determined target values. The RIMCS accuracy was found to be in the range of the LM uniform water depth application uniformity coefficients of 88–96%. The RIMCS was successfully transferred to another LM in North Dakota as indicated by the relatively low variable rate application errors of –8.8 ± 8.1% and −0.14 ± 6.7% for the two spans.     

Effects of in vitro brevetoxin exposure on apoptosis and cellular metabolism in a leukemic T cell line (Jurkat)

Harmful algal blooms (HABs) of the toxic dinoflagellate, Karenia brevis, produce red tide toxins, or brevetoxins. Significant health effects associated with red tide toxin exposure have been reported in sea life and in humans, with brevetoxins documented within immune cells from many species. The objective of this research was to investigate potential immunotoxic effects of brevetoxins using a leukemic T cell line (Jurkat) as an in vitro model system. Viability, cell proliferation, and apoptosis assays were conducted using brevetoxin congeners PbTx-2, PbTx-3, and PbTx-6. The effects of in vitro brevetoxin exposure on cell viability and cellular metabolism or proliferation were determined using trypan blue and MTT (1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan), respectively. Using MTT, cellular metabolic activity was decreased in Jurkat cells exposed to 5 – 10 μg/ml PbTx-2 or PbTx-6. After 3 h, no significant effects on cell viability were observed with any toxin congener in concentrations up to 10 μg/ml. Viability decreased dramatically after 24 h in cells treated with PbTx-2 or -6. Apoptosis, as measured by caspase-3 activity, was significantly increased in cells exposed to PbTx-2 or PbTx-6. In summary, brevetoxin congeners varied in effects on Jurkat cells, with PbTx-2 and PbTx-6 eliciting greater cellular effects compared to PbTx-3.     

Comparison of Quality Characteristics and Breadmaking Functionality of Hard Red Winter and Hard Red Spring Wheat

Various whole‐kernel, milling, flour, dough, and breadmaking quality parameters were compared between hard red winter (HRW) and hard red spring (HRS) wheat. From the 50 quality parameters evaluated, values of only nine quality characteristics were found to be similar for both classes. These were test weight, grain moisture content, kernel size, polyphenol oxidase content, average gluten index, insoluble polymeric protein (%), free nonpolar lipids, loaf volume potential, and mixograph tolerance. Some of the quality characteristics that had significantly higher levels in HRS than in HRW wheat samples included grain protein content, grain hardness, most milling and flour quality measurements, most dough physicochemical properties, and most baking characteristics. When HRW and HRS wheat samples were grouped to be within the same wheat protein content range (11.4–15.8%), the average value of many grain and breadmaking quality characteristics were similar for both wheat classes but significant differences still existed. Values that were higher for HRW wheat flour were color b*, free polar lipids content, falling number, and farinograph tolerance. Values that were higher for HRS wheat flour were geometric mean diameter, quantity of insoluble polymeric proteins and gliadins, mixograph mix time, alveograph configuration ratio, dough weight, crumb grain score, and SDS sedimentation volume. This research showed that the grain and flour quality of HRS wheat generally exceeds that of HRW wheat whether or not samples are grouped to include a similar protein content range.     

Zum Stand der Kenntnisse überProstephanus truncatus (Horn) (Col., Bostrichidae), einen gef?hrlichen Maissch?dling in Afrika

Es wird ein gedrängter Überblick über die Lebens- und Schadensweise sowie Möglichkeiten der Bekämpfung des BostrichidenProstephanus truncatus gegeben, der nach seiner Einschleppung aus Mittelamerika in Afrika zu einem gefürchteten Maisschädling werde. Besonders zahlreich vermehrt er sich in belieschten Maiskolben, eine in ländlichen Regionen der Tropen häufig praktizierte Lagerform. Neuere Untersuchungen deuten darauf hin, daß der Käfer die Kolben an der Pflanze schon vor der Einlagerung befällt.Die Verluste in Maislägern mitP. truncatus-Befall liegen durchschnittlich 4fach über dem sonst üblichen Niveau. Schätzungen ergaben, daß eine landesweite Ausbreitung des Schädlings in Kenia, das durch seine direkte Nachbarschaft mit dem außerordentlich stark betroffenen Tansania potentiell gefährdet ist, zu einem Ernteverlust von mindestens DM 33 Mio. pro Jahr führen würde. Dieser Ausfall müßte durch entsprechend hohe Importe ausgeglichen werden.     

玉米-豆粕日粮中添加有机锌和植酸酶对肉鸡生产性能和组织锌水平的影响

<正>美国NRC(1994)基于无机锌源和半纯合日粮的研究结果(O'Dell和Savage,1957;Roberson andSchaible,1958)推荐的肉鸡锌(Zn)需要量是40mg/kg。近年来,因有机微量元素的生物学利用率更高,粪便排泄量更少,使得有机微量元素(蛋白或氨基酸螯合物)的用量不断增加(Wedekind和Baker,1989;Wedekind等,1992;Cao等,2000;Ao等,2006)。