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151.
152.
Sornborger A Broder J Majumder A Srinivasamoorthy G Porter E Reagin SS Keith C Lauderdale JD 《Journal of the Optical Society of America. A, Optics, image science, and vision》2008,25(9):2185-2194
Ratiometric fluorescent indicators are used for making quantitative measurements of a variety of physiological variables. Their utility is often limited by noise. This is the second in a series of papers describing statistical methods for denoising ratiometric data with the aim of obtaining improved quantitative estimates of variables of interest. Here, we outline a statistical optimization method that is designed for the analysis of ratiometric imaging data in which multiple measurements have been taken of systems responding to the same stimulation protocol. This method takes advantage of correlated information across multiple datasets for objectively detecting and estimating ratiometric signals. We demonstrate our method by showing results of its application on multiple, ratiometric calcium imaging experiments. 相似文献
153.
Cloud computing affords lot of resources and computing facilities through Internet. Cloud systems attract many users with its desirable features. In spite of them, Cloud systems may experience severe security issues. Thus, it is essential to create an Intrusion Detection System (IDS) to detect both insider and outsider attacks with high detection accuracy in cloud environment. This work proposes an anomaly detection system at the hypervisor layer named Hypervisor Detector that uses a hybrid algorithm which is a mixture of Fuzzy C-Means clustering algorithm and Artificial Neural Network (FCM-ANN) to improve the accuracy of the detection system. The proposed system is implemented and compared with Naïve Bayes classifier and Classic ANN algorithm. The DARPA’s KDD cup dataset 1999 is used for experiments. Based on extensive theoretical and performance analysis, it is evident that the proposed system is able to detect the anomalies with high detection accuracy and low false alarm rate even for low frequent attacks thereby outperforming Naïve Bayes classifier and Classic ANN. 相似文献
154.
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156.
Chang Ho Kang Eun Seon Lee Ganesh M. Nawkar Joung Hun Park Seong Dong Wi Su Bin Bae Ho Byoung Chae Seol Ki Paeng Jong Chan Hong Sang Yeol Lee 《International journal of molecular sciences》2021,22(19)
Interaction between light signaling and stress response has been recently reported in plants. Here, we investigated the role of CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), a key regulator of light signaling, in endoplasmic reticulum (ER) stress response in Arabidopsis. The cop1-4 mutant Arabidopsis plants were highly sensitive to ER stress induced by treatment with tunicarmycin (Tm). Interestingly, the abundance of nuclear-localized COP1 increased under ER stress conditions. Complementation of cop1-4 mutant plants with the wild-type or variant types of COP1 revealed that the nuclear localization and dimerization of COP1 are essential for its function in plant ER stress response. Moreover, the protein amount of ELONGATED HYPOCOTYL 5 (HY5), which inhibits bZIP28 to activate the unfolded protein response (UPR), decreased under ER stress conditions in a COP1-dependent manner. Accordingly, the binding of bZIP28 to the BIP3 promoter was reduced in cop1-4 plants and increased in hy5 plants compared with the wild type. Furthermore, introduction of the hy5 mutant locus into the cop1-4 mutant background rescued its ER stress-sensitive phenotype. Altogether, our results suggest that COP1, a negative regulator of light signaling, positively controls ER stress response by partially degrading HY5 in the nucleus. 相似文献
157.
Ganesh Chandra Jagetia Manjeshwar Shrinath Baliga 《Molecular nutrition & food research》2002,46(5):332-336
The effect of 5, 10, 20, 40, 60, 80, 100, 120, and 160 mg/kg body weight (b.wt.) of aqueous extract of cystone (an ayurvedic herbal medicine) administered intraperitoneally was studied on the radiation‐induced mortality in mice exposed to 10 Gy of γ‐radiation. Treatment of mice with different doses of cystone, consecutively for five days before irradiation, delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non‐drug treated irradiated controls. The pretreatment of mice with different doses of cystone before exposure to 10 Gy of γ‐radiation resulted in a dose‐dependent elevation in the survival up to 40 mg/kg b. wt., where the highest number of survival (55.55%) was observed by 30 days post irradiation, when compared with the 10 Gy irradiated control (6.66%). Thereafter, the number of survivors declined and reached a nadir at 160 mg/kg, where no survivors could be observed. The optimum protection against irradiation was observed for 40 mg/kg cystone, where the highest number of survivors were reported by 30 days post irradiation and it was 8.34‐fold greater than that of the irradiated control group. 相似文献
158.
Sunghwan KIM Halil CEYLAN Kasthurirangan GOPALAKRISHNAN 《Frontiers of Structural and Civil Engineering》2014,8(2):101-114
In this study, finite element (FE)-based primary pavement response models are employed for investigating the early-age deformation characteristics of jointed plain concrete pavements (JPCP) under environmental effects. The FE-based ISLAB (two-and-one-half-dimensional) and EverFE (three-dimensional) software were used to conduct the response analysis. Sensitivity analyses of input parameters used in ISLAB and EverFE were conducted based on field and laboratory test data collected from instrumented pavements on highway US-34 near Burlington, Iowa. Based on the combination of input parameters and equivalent temperatures established from preliminary studies, FE analyses were performed and compared with the field measurements. Comparisons between field measured and computed deformations showed that both FE programs could produce reasonably accurate estimates of actual slab deformations due to environmental effects using the equivalent temperature difference concept. 相似文献
159.
This article presents the buckling analysis of orthotropic nanoplates such as graphene using the two-variable refined plate
theory and nonlocal small-scale effects. The two-variable refined plate theory takes account of transverse shear effects and
parabolic distribution of the transverse shear strains through the thickness of the plate, hence it is unnecessary to use
shear correction factors. Nonlocal governing equations of motion for the monolayer graphene are derived from the principle
of virtual displacements. The closed-form solution for buckling load of a simply supported rectangular orthotropic nanoplate
subjected to in-plane loading has been obtained by using the Navier’s method. Numerical results obtained by the present theory
are compared with first-order shear deformation theory for various shear correction factors. It has been proven that the nondimensional
buckling load of the orthotropic nanoplate is always smaller than that of the isotropic nanoplate. It is also shown that small-scale
effects contribute significantly to the mechanical behavior of orthotropic graphene sheets and cannot be neglected. Further,
buckling load decreases with the increase of the nonlocal scale parameter value. The effects of the mode number, compression
ratio and aspect ratio on the buckling load of the orthotropic nanoplate are also captured and discussed in detail. The results
presented in this work may provide useful guidance for design and development of orthotropic graphene based nanodevices that
make use of the buckling properties of orthotropic nanoplates. 相似文献
160.
Nicholson CL Firth EC Waterland MR Jones G Ganesh S Stewart RB 《Analytical chemistry》2012,84(7):3369-3375
Although bone fracture has become a serious global health issue, current clinical assessments of fracture risk based on bone mineral density are unable to accurately predict whether an individual is likely to suffer a fracture. There is increasing recognition that the chemical structure and composition, or microstructure, of mineralized tissues has an important role to play in determining the fracture resistance of bone. The objective of this preliminary study was to evaluate the use of specular reflectance Fourier transform infrared (SR FT-IR) microspectroscopy in conjunction with discriminant analysis as an innovative technique for providing future insights into the origins of orthopedic abnormalities. The impetus for this approach was that SR FT-IR microspectroscopy would offer several advantages over conventional transmission methods. Bone samples were obtained from young racehorses at known fracture predilection sites and spectra were successfully obtained from calcified cartilage and subchondral bone for the first time. By applying discriminant analysis to the spectral data set in biologically relevant regions, microstructural differences between groups of individuals were found to be related to features associated with both the mineral and organic components of the bone. The preliminary findings also suggest that differences in bone microstructure may exist between healthy individuals of the same age, raising important questions around the normal limits of individual variation and whether individuals may be predisposed to later fracture as a result of detrimental microstructural changes during early growth and development. 相似文献