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61.
This research investigated mothers' affect in the context of children's homework. Mothers (N=109) of children 8 to 12 years old were interviewed daily about their affect while interacting with children, their assistance with children's homework, and children's behavior while completing homework. At this time and 6 months later, children's motivational and emotional functioning was assessed. Although mothers' negative affect was lower than their positive affect, it was elevated on days their assistance with homework was high. This was accounted for by mothers' perceptions of children as helpless on days they provided heightened assistance. Mothers' positive affect in the homework context buffered children's motivational and emotional functioning against mothers' negative affect as well as children's helplessness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
John T. Y. Wu Sally Dreger Eva Y. W. Chow Evelyn E. Bowlby Lester S. Y. Wong 《Journal of The Association for Laboratory Automation》2003,8(1):46
An enzyme-linked immunosorbent assay (ELISA) for Neospora caninum antibodies was automated with a robotic workstation, the Beckman Coulter Biomek 2000, to screen 200 bovine sera. Comparing these results with manually run ELISA data, a 95.92% agreement (K = 0.9592) between the two assays was obtained. The automated assay was specific and sensitive with excellent positive and negative predictive values. The results were repeatable and reproducible. The automation flexibility was high and the operation complexity was minimal. High-throughput screening (HTS) for bovine antibodies to Neospora caninum was achieved. The assay was developed according to the internationally recognized ISO17025 standard requirements. 相似文献
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64.
Josep Llosa Eduard Ayguadé Mateo Valero 《International journal of parallel programming》1998,26(2):121-142
Software Pipelining is a loop scheduling technique that extracts loop parallelism by overlapping the execution of several consecutive iterations. One of the drawbacks of software pipelining is its high register requirements, which increase with the number of functional units and their degree of pipelining. This paper analyzes the register requirements of software pipelined loops. It also evaluates the effects on performance of the addition of spill code. Spill code is needed when the number of registers required by the software pipelined loop is larger than the number of registers of the target machine. This spill code increases memory traffic and can reduce performance. Finally, compilers can apply transformations in order to reduce the number of memory accesses and increase functional unit utilization. The paper also evaluates the negative effect on register requirements that some of these transformations might produce on loops. 相似文献
65.
This paper is devoted to the study of the feedback passivity property in nonlinear discrete-time systems. The relative degree and zero dynamics of the non-passive system are related to the feedback passivity of the system. Two main results are presented. First, some relative degree-related properties of passive systems in general form are stated. Second, sufficient conditions in order to render a multiple-input multiple-output (MIMO) system passive by means of a static state feedback control law are obtained. 相似文献
66.
Del Moral ML Esteban FJ Hernández R Blanco S Molina FJ Martínez-Lara E Siles E Viedma G Ruiz A Pedrosa JA Peinado MA 《Microscopy research and technique》2004,64(4):304-311
To ascertain the possible implications of the nitric oxide (NO*) producing system in striatal senescence, and by using immunohistochemistry and image-processing approaches, we describe the presence of the enzyme nitric oxide synthase (NOS), the NADPH-diaphorase (NADPH-d) histochemical marker, and nitrotyrosine-derived complexes (N-Tyr) in the striatum of adult and aged rats. The results showed neuronal NOS immunoreactive (nNOS-IR) aspiny medium-sized neurons and nervous fibres in both age groups, with no variation in the percentage of immunoreactive area but a significant decrease in the intensity and in the number of somata with age, which were not related to the observed increase with age of the striatal bundles of the white matter. In addition, NADPH-d activity was detected in neurons with morphology similar to that of the nNOS-IR cells; a decrease in the percentage of area per field and in the number of cells, but an increase in the intensity of staining for the NADPH-d histochemical marker, were detected with age. The number of neuronal NADPH-d somata was higher than for the nNOS-IR ones in both age groups. Moreover, N-Tyr-IR complexes were observed in cells (neurons and glia) and fibres, with a significant increase in the percentage of the area of immunoreaction, related to the increase of white matter, but a decrease in intensity for the aged group. On the other hand, we did not detect the inducible isoform (iNOS) either in adult or in aged rats. Taken together, these results support the contention that NADPH-d staining is not such an unambiguous marker for nNOS, and that increased protein nitration may participate in striatal aging. 相似文献
67.
Eva Dreussi Erika Cecchin Jerry Polesel Vincenzo Canzonieri Marco Agostini Caterina Boso Claudio Belluco Angela Buonadonna Sara Lonardi Francesca Bergamo Sara Gagno Elena De Mattia Salvatore Pucciarelli Antonino De Paoli Giuseppe Toffoli 《International journal of molecular sciences》2016,17(9)
Background: Pathological complete response (pCR) to neoadjuvant chemoradiotherapy (CRT) in locally advanced rectal cancer (LARC) is still ascribed to a minority of patients. A pathway based-approach could highlight the predictive role of germline single nucleotide polymorphisms (SNPs). The primary aim of this study was to define new predictive biomarkers considering treatment specificities. Secondary aim was to determine new potential predictive biomarkers independent from radiotherapy (RT) dosage and cotreatment with oxaliplatin. Methods: Thirty germ-line SNPs in twenty-one genes were selected according to a pathway-based approach. Genetic analyses were performed on 280 LARC patients who underwent fluoropyrimidine-based CRT. The potential predictive role of these SNPs in determining pathological tumor response was tested in Group 1 (94 patients undergoing also oxaliplatin), Group 2 (73 patients treated with high RT dosage), Group 3 (113 patients treated with standard RT dosage), and in the pooled population (280 patients). Results: Nine new predictive biomarkers were identified in the three groups. The most promising one was rs3136228-MSH6 (p = 0.004) arising from Group 3. In the pooled population, rs1801133-MTHFR showed only a trend (p = 0.073). Conclusion: This exploratory study highlighted new potential predictive biomarkers of neoadjuvant CRT and underlined the importance to strictly define treatment peculiarities in pharmacogenetic analyses. 相似文献
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69.
Non-linear diffusion (ND) is an iterative difference equation used in several image processing applications such as denoising, segmentation, or compression. The number of iterations required to achieve optimal processing can be very high, making ND not suitable for real-time requirements. In this paper, we study how to reduce complexity of ND so as to achieve minimal number of iterations for real-time image denoising. To do this, we first study the relations between parameters of the iterative equation: the number of iterations, the time step, and the edge strength. We then proceed by estimating the minimally required number of iterations to achieve effective denoising. Then, we relate the edge strength to the number of iterations, to noise, and to the image structure. The resulted minimal iterativity ND is very fast, while still achieves similar or better noise reduction compared to related ND work. This paper also shows how the proposed spatial filter is suitable for structure-sensitive object segmentation and temporal noise reduction. 相似文献
70.
We study finitely generated and finite systems defined by linear partial difference equations with constant coefficients in a Noetherian ring. The two notions coincide for finite rings, and we show that all finite systems exhibit certain periodicity properties. For the particular case of systems over the ring of integers modulo m?>?1, which is important in coding theory, a method is given for determining the number of trajectories, using Gr?bner basis techniques. 相似文献