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951.
For the primary isolation of Mycobacterium bovis from bovine lesions, 1-hexadecylpyridinium chloride (HPC) at a concentration of 0.75% was as effective as 2% NaOH in controlling the growth of contamination. The advantages of using HPC over NaOH are that it is a rapid one-step procedure not requiring neutralisation with acid, it is less toxic to M. bovis thus increasing isolation rates, and it promotes the earlier appearance of colonies. 相似文献
952.
E.O. Balogun J.B. Balogun S. Yusuf H.M. Inuwa I.S. Ndams P. Sheridan D.K. Inaoka T. Shiba S. Harada K. Kita K.A.N. Esievo A.J. Nok 《Veterinary parasitology》2014,199(3-4):259-263
African trypanosomosis is a potentially fatal disease that is caused by extracellular parasitic protists known as African trypanosomes. These parasites inhabit the blood stream of their mammalian hosts and produce a number of pathological features, amongst which is anemia. Etiology of the anemia has been partly attributed to an autoimmunity-like mediated erythrophagocytosis of de-sialylated red blood cells (dsRBCs) by macrophages. Lactose infusion to infected animals has proven effective at delaying progression of the anemia. However, the mechanism of this anemia prevention is yet to be well characterized. Here, the hypothesis of a likely induced further modification of the dsRBCs was investigated. RBC membrane galactose (RBC m-GAL) and packed cell volume (PCV) were measured during the course of experimental trypanosomosis in mice infected with Trypanosoma congolense (stb 212). Intriguingly, while the membrane galactose on the RBCs of infected and lactose-treated mice (group D) decreased as a function of parasitemia, that of the lactose-untreated infected group (group C) remained relatively constant, as was recorded for the uninfected lactose-treated control (group B) animals. At the peak of infection, the respective cumulative percent decrease in PCV and membrane galactose were 30 and 185 for group D, and 84 and 13 for group C. From this observed inverse relationship between RBCs membrane galactose and PCV, it is logical to rationalize that the delay of anemia progression during trypanosomosis produced by lactose might have resulted from an induction of galactose depletion from dsRBCs, thereby preventing their recognition by the macrophages. 相似文献
953.
K. Vandersypen A. C. T. Keita K. Kaloga Y. Coulibaly D. Raes J.‐Y. Jamin 《Irrigation and Drainage》2006,55(1):51-60
The Office du Niger is a centrally managed collective irrigation scheme of 80 000 ha, mainly cultivated with flooded rice. In the context of recent reforms, water distribution and maintenance at the tertiary canal level were left to farmers. In this paper, their ability to resolve collective action problems through devising, monitoring and enforcing rules is diagnosed through a questionnaire survey of 89 farmers on 59 tertiary canals from five villages. Results show that rules are devised only on 30 and 24% of the canals for water distribution and maintenance respectively. Moreover, there is often no consensus on rules among farmers, and monitoring and sanctioning mechanisms are absent. This results in individualistic behavior causing problems concerning water distribution and maintenance for respectively 20 and 43% of the interviewed farmers. Ineffectiveness of peer pressure and farmers' incomplete mentality shift towards assuming collective responsibility are impediments to successful organization of water management. With water supply being abundant and the infrastructure recently rehabilitated, organization of water management at tertiary level is, however, not always required in order to avoid problems. On the other hand, the current state of affairs is not considered sustainable, as the irrigated area will strongly expand and the irrigation infrastructure ages with time. Measures of sensitization and group empowerment accompanying the process of management transfer will therefore be desirable. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
954.
P. S. Minhas N. K. Tyagi S. K. Gupta K. L. Dong L. G. Cai L. S. Pereira 《Irrigation and Drainage》2006,55(5):463-477
For assessing the potential and need to reuse surface drainage and groundwater for sustainable crop production in the Shandong province of the Yellow River basin, inventories were made on the quality of alternative sources of irrigation and on the yields achieved by farmers using those waters for irrigation. Drainage and groundwater quality (EC < 2 dS m−1) in most parts of Huimin and Yangxin counties favors their use for irrigation but there can be some limitations in Wudy as the salinity increases towards the sea. Yield–soil salinity functions were developed for both maize and wheat; for the latter, functions depend upon the number of irrigations applied. Simulations using the SWAP model showed that yields of wheat and maize could be sustained with the reuse of drainage water having a salt content up to 4 mg cm−3. There is a clear benefit from using drainage water for the last two wheat irrigations relative to deficit irrigation despite water salinity. Monsoon rainfall should help to maintain a favorable salt balance, thus to avoid salt build‐up along the soil profile. Results indicate that the reuse of drainage waters offers opportunities for improving irrigation water management in wheat for areas facing water shortage. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
955.
Adoption of irrigation scheduling techniques in South African sugarcane production has been disappointing. The challenge is to use state of the art technology to provide practical and useful advice to farmers and further to convince farmers of the benefits of irrigation scheduling by on‐farm demonstration. The purpose of this paper is to describe (1) a high‐technology system to provide practical, real‐time irrigation advice and (2) its pilot implementation on a small‐scale farm irrigation scheme. The system consists of a web‐based simulation model that estimates the recent, current and future water balance, crop status and yield from field information and real‐time weather data. The system automatically generates and distributes simple irrigation advice by SMS to farmers' cellular phones. The system was evaluated on a small‐scale sugarcane irrigation scheme at Pongola, South Africa. Indications are that adhering to advice from this system leads to large reductions in irrigation applied (33%), deep drainage (64%) and irrigation costs. Yields are not affected significantly and profitability is enhanced considerably. The main impact is to reduce irrigation during winter and when the crop is young. Results suggest that the phased expansion of the system to more farmers and other irrigation schemes is warranted. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
956.
957.
Granier A Anfodillo T Sabatti M Cochard H Dreyer E Tomasi M Valentini R Bréda N 《Tree physiology》1994,14(12):1383-1396
Axial water flow in the trunks of mature oak trees (Quercus petraea (Matt.) Liebl. and Q. robur L.) was studied by four independent techniques: water absorption from a cut trunk, sap flowmeters, heat pulse velocity (HPV) and thermoimaging. Estimation of the total water flow with sap flowmeters, HPV and water absorption yielded comparable results. We concluded from dye colorations, thermograms and axial profiles of sap flow and heat pulse velocity that, in intact trunks, most of the flow occurred in the current-year ring, where early-wood vessels in the outermost ring were still functional. Nevertheless, there was significant flow in the older rings of the xylem. Total water flow through the trunk was only slightly reduced when air embolisms were artificially induced in early-wood vessels, probably because there was little change in hydraulic conductance in the root-leaf sap pathway. Embolization of the current-year vessels reactivated transport in the older rings. 相似文献
958.
Nakagawa T Watanabe M Ohashi E Uyama R Takauji S Mochizuki M Nishimura R Ogawa H Sugano S Sasaki N 《Research in veterinary science》2006,80(3):317-323
We characterised cultured canine mammary gland adenocarcinoma cells by exhaustive step protein expression analysis to identify factors associated with tumour progression or metastasis of canine mammary gland tumour. Cultured adenocarcinoma cells derived from a total of 3 primary and 3 metastatic lesions from 3 dogs (CHMp/m, CIPp/m and CNMp/m, where CHM, CIP, and CNM indicate the 3 animals) were used in this study. The expression of 24 proteins reported to be related to tumourigenesis or malignancy of human breast cancers were examined by Western blot analysis using 24 antibodies. The expression of sialyl Lewis X [sLe(x)] was only observed in CHMm cells, which were derived from pleural effusion. This expression was further confirmed by immunohistochemistry. The levels of some factors, such as 14-3-3sigma, cyclinD1 and Rb, differed among cells or between the primary and metastatic cells in the pair. Though the difference in their expression was not consistent within the cells from primary and metastatic origin, this characterisation should provide useful information for further molecular analysis of these cultured cells. Since some of the factors, such as sLe(x), 14-3-3sigma, cyclinD1 and Rb, showed different levels of expression in the pair, these cultured cells might be meaningful tools for clarification of distant metastasis in canine mammary gland tumours. 相似文献
959.
The reduction in agricultural water use in areas of scarce supplies can release significant amounts of water for other uses. As improvements in irrigation systems and management have been widely adopted by fruit tree growers already, there is a need to explore the potential for reducing irrigation requirements via deficit irrigation (DI). It is also important to quantify to what extent the reduction in applied water through DI is translated into net water savings via tree evapotranspiration (ET) reduction. An experiment was conducted in a commercial pistachio orchard in Madera, CA, where a regulated deficit irrigation (RDI) program was applied to a 32.3-ha block, while another block of the same size was fully irrigated (FI). Four trees were instrumented with six neutron probe access tubes each, in the two treatments and the soil water balance method was used to determine tree ET. Seasonal irrigation water in FI, applied through a full-coverage microsprinkler system, amounted to 842 mm, while only 669 mm were applied in RDI. Seasonal ET in FI was 1024 mm, of which 308 mm were computed as evaporation from soil (Es). In RDI, seasonal ET was reduced to 784 mm with 288 mm as Es. The reduction in applied water during the deficit period amounted to 147 mm. The ET of RDI during the deficit period was also reduced relative to that of FI by 133 mm, which represented 33% of the ET of FI during the deficit irrigation period. There was an additional ET reduction in RDI of about 100 mm that occurred in the post-deficit period. 相似文献
960.
The Zhanghe Irrigation System (ZIS), in Central China, has drawn attention internationally because it managed to sustain its rice production in the face of a dramatic reallocation of water to cities, industries and hydropower uses. Ponds, the small reservoirs ubiquitous in the area, are hypothesized to have been instrumental in this. Ponds are recharged by a combination of return flows from irrigation and runoff from catchment areas within the irrigated perimeter. They provide a flexible, local source of irrigation water to farmers. This paper assesses the storage capacity and some key hydrological properties of ponds in a major canal command within ZIS. Using remote sensing data (Landsat and IKONOS) and an area–volume relationship based on a field survey, we obtained an overall pond storage capacity of 96 mm (per unit irrigated area). A comparative analysis between 1978 and 2001 reveals that part of this capacity results from a very significant development of ponds (particularly in the smaller range of sizes) in the time interval, probably as a response to rapidly declining canal supplies. We developed a high-resolution digital elevation model from 1:10,000 topographic maps to support a GIS-based hydrological analysis. Pond catchments were delineated and found to extensively overlap, forming hydrological cascades of up to 15 units. In a 76-km2 area within the irrigation system, we found an average of close to five ‘connected’ ponds downstream of each irrigated pixel. This high level of connectivity provides opportunities for multiple reuses of water as it flows along toposequences. A fundamental implication is that field ‘losses’ such as seepage and percolation do not necessarily represent losses at a larger scale. Such scale effects need to be adequately taken into account to avoid making wrong assumptions about water-saving interventions in irrigation. 相似文献