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Introduction: Working memory (WM) refers to the temporary storage and manipulation of information. Short-term memory storage can be divided into separate subsystems for verbal information and visual information. We explored the capacity of visual WM in patients with temporal lobe glioma. Methods: In this study, we assessed 30 patients with temporal lobe glioma and 30 healthy controls (HCs) using a method that combined memory tests with visual WM tasks (digital span task, spatial capacity N-back task, and emotional N-back task). Results: The results revealed that groups did not differ in terms of demographics, estimated intelligence, and level of psyc distress. For visual WM tasks, statistically significant differences were not found on the 1-back tasks and forward versions of simple span tasks between the temporal patient (TP) group and the HC group. Analysis of correct responses of the experimental tasks suggested that the TP group was significantly different from the HC group in the 2-back tasks and backward versions of simple span tasks. For reaction times, spatial capacity 2-back task and emotional 2-back task showed the TP group was significantly different from the HC group. Conclusion: These findings revealed that visual WM scores of temporal glioma patients were lower than HCs, and hence, the temporal lobe may be a certain neuroanatomical structure in the WM network. [ABSTRACT FROM AUTHOR]

Plant roots and microorganisms play an important role in the soil N cycle and plant N nutrition through the release of extracellular enzymes. In the present greenhouse pot experiment, wheat ( Triticum aestivum) seedlings were grown in a fluvo-aquic soil (Udifluvent) to investigate N mineralization and utilization in the rhizosphere of wheat. The soil received chemical fertilizer (N-labeled urea), chemical fertilizer plus manure (common urea + N-labeled swine manure) or no N. Plant roots were separated from the soil with a nylon cloth, and 1-mm increments of soil moving laterally away from roots were analyzed for N, microbial C, and the activities of invertase, urease and protease. Chemical fertilizer plus manure promoted wheat growth and N absorption significantly compared with chemical fertilizer. N from both chemical fertilizer and swine manure accumulated significantly in the rhizosphere soil within 5 mm of the roots. Fertilized N could thus move easily laterally towards roots and there was no indication that movement through the soil limited plant N supply. A large proportion of fertilizer N was lost from the soil during the wheat growing period, and N utilization efficiency was 24% for chemical fertilizer and 30% for swine manure. In addition, faster rates of N mineralization, larger amounts of microbial C, and increased activities of invertase, urease and protease occurred in the rhizosphere compared with other parts of the soil. There was a significant correlation between microbial C and N mineralization rate ( r = 0.968, P < 0.01) in the whole soil. Microbial C also showed significant positive correlations with activities of invertase ( r = 0.892, P < 0.01) and protease ( r = 0.933, P < 0.01). Further study showed that adding manure into soil increased microbial C and the activities of invertase and protease; adding urea stimulated urease activity in the same soil. Changes in soil enzyme activities in response to N fertilizers could be considered indicators for different fertilizer managements. [ABSTRACT FROM AUTHOR]

Abstract: Successful nitrogen (N) management requires better synchronization between crop N demand and N supply from all sources throughout crop growing season. An in-season N management strategy based on soil Nmin test had been developed under experimental conditions, and more than half-N fertilizer could be saved without grain yield losses, compared with farmer''s N management practices. The objective of this study was to evaluate this in-season N management strategy for winter wheat (Triticum aestivum L.) in different farmers’ fields of North China Plain (NCP). A total of 121 on-farm N-response experiments (check with no N fertilizer, in-season N management based on soil Nmin test, and farmer''s practice) were conducted in seven key winter wheat production regions of NCP from 2003 to 2005. The average N rate determined with in-season N management strategy (128kgNha−1) was significantly lower than farmer''s practice (325kgNha−1) without wheat grain yield losses. As a result, in-season N management strategy significantly increased economic gains by $144ha−1, reduced residual nitrate-N content in the top 90cm soil layer and N losses by 81 and 118kgNha−1, respectively (P <0.05). Recovery N efficiency (REN), agronomic N use efficiency (AEN) and N partial factor productivity (PFPN) were significantly improved to 44%, 11 and 56kgkg−1, respectively, compared with farmer''s N practice (REN, 18%; AEN, 3kgkg−1; PFPN, 20kgkg−1). Effective use of soil N supply and better synchronization between crop N demand and supply were main reasons for the increased N use efficiency. We conclude that the in-season N management strategy based on soil Nmin test can be applied for winter wheat production in NCP for improved N use efficiency and reduced environmental contamination. [Copyright &y& Elsevier]