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Abstract

The aim of this study was to use the FAO-56 single and dual crop coefficient approaches to estimate actual evapotranspiration (ETa) over an irrigated citrus orchard under drip and flood irrigations in Marrakech, Morocco. The results showed that, by using crop coefficients suggested in the FAO-56 paper, the performance of both approaches was poor for two irrigation treatments. The Root Mean Squared Error (RMSE) between measured and simulated ETa values over the citrus orchard under drip irrigation was about 1.43 and 1.27 mm/day for the single and dual approaches, respectively, while the corresponding statistics for the orchard irrigated by the flooding technique was 1.87 and 2.48 mm/day. After determination of the appropriate values of the crop coefficient (Kc) based on eddy covariance measurements of ETa, the performance of both approaches greatly improved. The obtained Kc values were lower than the FAO-56 values by about 20%. The low Kc values obtained reflect the practice of drip irrigation for one field and the low value of cover fraction for the other field. Additionally, the efficiency of the irrigation practices was investigated by comparing the measured Kc for two fields. The results showed that a considerable amount of water was lost by direct soil evaporation from the citrus orchard irrigated by flooding technique.  相似文献   
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In the present study a new species of the genus Anabolia, A. anatolica sp. n. from the Taurus Mountains in southern Anatolia is described and illustrated. The new species is related to A. laevis Zetterstedt, 1840 from northern Europe and is a glacial relict species of Pleistocene origin.  相似文献   
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The functions of the neuronal microtubule-associated protein Tau in the central nervous system are regulated by manifold posttranslational modifications at more than 50 sites. Tau in healthy neurons carries multiple phosphate groups, mostly in its microtubule assembly domain. Elevated phosphorylation and aggregation of Tau are widely considered pathological hallmarks in Alzheimer’s disease (AD) and other tauopathies, triggering the quest for Tau posttranslational modifications in the disease context. However, the phosphorylation patterns of physiological and pathological Tau are surprisingly similar and heterogenous, making it difficult to identify specific modifications as therapeutic targets and biomarkers for AD. We present a concise summary of - and view on - important previous and recent advances in Tau phosphorylation analysis in the context of AD.  相似文献   
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A procedure in which combined molecular phylogeographical analyses among populations of Hemerocallis middendorfii (Hemerocallidaceae, Asparagales) were applied allowed comparisons to be made with the geological history. Information on geographical areas in which synapomorphic mutations occurred was used in molecular phylogeographical analyses for the first time in this study, in addition to molecular maximum-parsimonious analyses and TCS analyses. Nucleotide sequences of the intergenic region between the rbcL and atpB genes and the trnL (UAA) intron in chloroplast DNA were analyzed for 28 Japanese and three Chinese populations of H. middendorfii, 10 populations of closely related species and four outgroup species. The data of the three analyses in general agreed with one another and indicated that the separation of this species had proceeded in conjunction with the geological vicariance or orogeny. Where the synapomorphic mutations occurred, three patterns were recognized. They correlated with the geological history, namely, the age when the Japanese Archipelago and the Continent had joined, when the Sea of Japan was formed, and when there was separation from the Continent and the formation of each of the islands in the Japanese Archipelago. It was suggested that ancestors of H. middendorfii originated at latest 25 million years ago when the Japanese Archipelago and the Continent had joined; that is, before the formation of the Sea of Japan.We are greatly obliged to three anonymous reviewers for their constructive comments.  相似文献   
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Rac1 plays a key role in neurite outgrowth via reorganization of the actin cytoskeleton. The molecular mechanisms underlying Rac1-mediated actin dynamics in the cytosol and plasma membrane have been intensively studied, but the nuclear function of Rac1 in neurite outgrowth has not yet been addressed. Using subcellular fractionation and immunocytochemistry, we sought to explore the role of nuclear Rac1 in neurite outgrowth. bFGF, a strong agonist for neurite outgrowth in PC12 cells, stimulated the nuclear accumulation of an active form of Rac1. Rac1-PBR (Q) mutant, in which six basic residues in the polybasic region at the C-terminus were replaced by glutamine, didn’t accumulate in the nucleus. In comparison with control cells, cells expressing this mutant form of Rac1 displayed a marked defect in extending neurites that was concomitant with reduced expression of MAP2 and MEK-1. These results suggest that Rac1 translocation to the nucleus functionally correlates with bFGF-induced neurite outgrowth. [BMB Reports 2013; 46(12): 617-622]  相似文献   
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