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针对电力系统多因素负荷预测问题的复杂性,结合粗糙集理论与GM(1,N)模型各自的优势,提出一种基于粗糙集理论的GM(1,N)预测模型.采取粗糙集理论对影响负荷预测因素进行简约,利用GM(1,N)建立简约后的因素变量和负荷之间的关系建立模型,并与GM(1,1)预测模型进行了比较,结果反映基于粗糙集理论的GM(1,N)预测模型的优越性,精准度达到94.055%.  相似文献   

3.
In this paper we extend the works of Baillie and Baltagi (1999, in Analysis of Panels and Limited Dependent Variables Models, Hsiao C et al. (eds). Cambridge University Press: Cambridge, UK; 255–267) and generalize certain results from the Baltagi and Li (1992, Journal of Forecasting 11 : 561–567) paper accounting for AR(1) errors in the disturbance term. In particular, we derive six predictors for the one‐way error components model, as well as their associated asymptotic mean squared error of multi‐step prediction in the presence of AR(1) errors in the disturbance term. In addition, we also provide both theoretical and simulation evidence as to the relative efficiency of our alternative predictors. The adequacy of the prediction AMSE formula is also investigated by the use of Monte Carlo methods and indicates that the ordinary optimal predictor performs well for various accuracy criteria. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

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Summary Synergistic effects of TA on gibberellin-dependent reactions in spermatophytes are not detectable in gametophytes of the fernAnemia phyllitidis where gibberellin substitutes for antheridiogens with regard to induction of male sexual organs and dark germination. In this archegoniate TA caused a significant reduction in growth rate and morphogenesis of the gametophytes, inhibitions that were not abolished by simultaneous application of gibberellin.  相似文献   

5.
Summary The inhibitory effect of four flavonoid compounds on virus multiplication and their influence on the intracellular cyclic AMP (cAMP) level were studied in cell cultures. Quercetin and quercitrin reduced the yields ofHuman (alpha) herpesvirus 1 (HSV-1) andSuid (alpha) herpesvirus 1 (pseudorabies virus), but hesperidin and rutin had no effect. Further, quercetin and quercitrin elevated the intracellular level of cAMP, whereas hesperidin and rutin did not alter the cAMP level. Both antiviral activity and cAMP-enhancing effect were dependent on the concentrations of the flavonoids, and these effects turned out to be parallel.This study suggests that a relation exists between the antiviral effect and the cAMP-enhancing activity of flavonoids.  相似文献   

6.
国内外环境材料最新研究进展   总被引:7,自引:0,他引:7  
介绍了环境材料的概念,对近期国内外在环境材料理论和应用研究领域取得的进展进行了综述,指出了未来环境材料研究的发展方向。  相似文献   

7.
The DSCR1 (Adapt78) gene1 is transiently induced by stresses to temporarily protect cells against further potentially lethal challenges. However, chronic expression of the DSCR1 (Adapt78) gene has now been implicated in several pathological conditions including Alzheimer’s disease, Down syndrome and cardiac hypertrophy. Calcipressin 1 has been shown to function through direct binding and inhibition of the serine threonine protein phosphatase Calcineurin. Pharmacological inhibition of calcineurin, by the immunosuppressive drugs cyclosporin A and FK506, affects a wide variety of diseases. It is, therefore, likely that this endogenous calcineurin inhibitor, calcipressin 1, may also play a role in a variety of human diseases. 1Please note that the mammalian DSCR1 gene is also called Adapt78 or RCAN1, and its protein products have been named Calcipressin1, MCIP1 and RCAN1. A proposal to adopt a single gene name of RCAN1 and a protein name RCAN1 (for Regulator of Calcineurin) has been endorsed by the HUGO Gene Nomenclature Committee, but final approval must await agreement from a majority of researchers in the field. Received 2 March 2005; received after revision 27 May 2005; accepted 19 July 2005  相似文献   

8.
Poly(ADP-ribose) (PAR) has been identified as a DNA damage-inducible cell death signal upstream of apoptosis-inducing factor (AIF). PAR causes the translocation of AIF from mitochondria to the nucleus and triggers cell death. In living cells, PAR molecules are subject to dynamic changes pending on internal and external stress factors. Using RNA interference (RNAi), we determined the roles of poly(ADP-ribose) polymerases-1 and -2 (PARP-1, PARP-2) and poly(ADP-ribose) glycohydrolase (PARG), the key enzymes configuring PAR molecules, in cell death induced by an alkylating agent. We found that PARP-1, but not PARP-2 and PARG, contributed to alkylation-induced cell death. Likewise, AIF translocation was only affected by PARP-1. PARP-1 seems to play a major role configuring PAR as a death signal involving AIF translocation regardless of the death pathway involved. Received 7 November 2007; received after revision 19 December 2007; accepted 21 December 2007 O. Cohausz, C. Blenn: These two authors contributed equally to this work.  相似文献   

9.
Summary A random distribution of the Y-chromosome at somatic metaphase was found in 50 patients with Ph' positive chronic myelogenous leukemia (CML). Thus, it is concluded that the positive of the Y-chromosome at somatic metaphase does not appear to influence the loss from bone marrow cells.  相似文献   

10.
We used the X chromosomes ofMicrotus cabrerae as a model to analyze the distribution of sister chromatid exchanges (SCEs) on different types of chromatin, because of the marked heterogeneity of the heterochromatin in the entire short arm and a portion of the long arm of this chromosome. Computer-simulated distributions, according to an algorithm that makes it possible to modify the distribution on the basis of any possible hypothesis, were compared with real distributions by log-linear models. We found that the frequency of SCEs in different types of heterochromatin was higher than that expected for a random distribution, and located an SCE hot-spot at the junction between euchromatin and heterochromatin. The possible relationship between the distribution of SCEs and base composition or chromatin accessibility are discussed.  相似文献   

11.
目的了解难治性癫痫患者脑组织中SCG10和MAPK的表达,探讨其在难治性癫痫发生、发展中的作用。方法按随机化原则,在我们建立的难治性癫痫患者术后脑组织库中抽取36例患者的脑组织,用免疫组织化学分别检测SCG10和MAPK的表迭,与16例对照组进行比较。并采用免疫荧光双标的方法,检测SCG10和MAPK在病例组中的表达情况。结果免疫组化检测到SCG10在实验组表达(0.4674±0.0258),高于对照(0.3405±0.0207),两组比较有显著性差异(P〈0.05);MAPK在实验组表达(0.4217±0.0141),同样也高于对照组(0.3189±0.1422,P〈0.05)。免疫荧光双标法,显示SCG10和MAPK表达在同一细胞上。讨论SCG10与MAPK在难治性癫痫患者的脑组织中表达增加,以及它们的共同表达,提示两者的相互作用可能是难治性癫痫发生发展中的一个重要因素。  相似文献   

12.
It is proved that formula for least squares extrapolation in stationary non‐linear AR(1) process is valid also for non‐stationary non‐linear AR(1) processes. This formula depends on the distribution of the corresponding white noise. If the non‐linear function used in the model is non‐decreasing and concave, upper and lower bounds are derived for least squares extrapolation such that the bounds depend only on the expectation of the white noise. It is shown in an example that the derived bounds in some cases give a good approximation to the least squares extrapolation. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

13.
Gene conversion was first defined in yeast as a type of homologous recombination in which the donor sequence does not change. In chicken B cells, gene conversion builds the antigen receptor repertoire by introducing sequence diversity into the immunoglobulin genes. Immunoglobulin gene conversion continues at high frequency in an avian leukosis virus induced chicken B cell line. This cell line can be modified by homologous integration of transfected DNA constructs offering a model system for studying gene conversion in higher eukaryotes. In search for genes which might participate in chicken immunoglobulin gene conversion, we have identified chicken counterparts of the yeastRAD51, RAD52, andRAD54 genes. Disruption and overexpression of these genes in the chicken B cell line may clarify their role in gene conversion and gene targeting.  相似文献   

14.
The role of insulin and IGF-1 signaling in longevity   总被引:16,自引:0,他引:16  
There are many theories of aging and parameters that influence lifespan, including genetic instability, telomerase activity and oxidative stress. The role of caloric restriction, metabolism and insulin and insulin-like growth factor-1 signaling in the process of aging is especially well conserved throughout evolution. These latter factors interact with each other, the former factors and histone deacetylases of the SIR family in a complex interaction to influence lifespan.Received 8 July 2004; received after revision 25 August 2004; accepted 17 September 2004  相似文献   

15.
Protein ubiquitination has critical roles in neuronal physiology and defects in protein ubiquitination have been implicated in neurodegenerative pathology. The anaphase-promoting complex/cyclosome (APC/C) is one of two key E3 ubiquitin ligase complexes that functions in regulating cell cycle transitions in proliferating cells by acting on cyclins and components of the mitotic/meiotic apparatus. Documentation of APC/C's action beyond cell division is sparse. In the past year, however, novel and surprising roles for APC/C in postmitotic neurons, particularly in the modulation of axonal growth and synaptic functions, have been revealed. APC/C and its activator Cdh-1 are found in good abundance in neurons, and these seem to function at different cellular locations, modulating apparently diverse processes such as axonal growth and synaptic function. Interestingly, there also appears to be a single link to these apparently divergent actions of APC/C in neurons--the multi-domain, multi-functional scaffolding protein Liprin-alpha which is an APC/C substrate.  相似文献   

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