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Plasmonics - In this paper, we demonstrate a plasmonic ultrahigh narrowband perfect absorber, which realizes an absorption intensity of up to 99.99% in the near-infrared electromagnetic spectrum... 相似文献
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The emergence of numerous genome projects has made the experimental classification of the protein localization almost impossible due to the exponential increase in the number of protein samples. However, most of the applications are merely developed for single-plex and completely ignored the presence of one protein at two or more locations in a cell. In this regard, few attempts were carried out to target Multi-label protein localizations; consequently, undesirable accuracies are achieved. This paper presents a novel approach, in which a discrete feature extraction method is fused with physicochemical properties of amino acids by using Chou's general form of Pseudo Amino Acid Composition. The technique is tested on two benchmark datasets namely: Gpos-mploc and Virus-mPLoc. The empirical results demonstrated that the proposed method yields better results via two examined classifiers i.e. ML-KNN and Rank-SVM. It is established that the proposed model has improved values in all performance measures considered for the comparison. 相似文献
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Obaid Ullah Beg Hedvig von Bahr-Lindström Zafar H. Zaidi Hans Jörnvall 《Bioscience reports》1984,4(12):1065-1070
A small protein (Mr about 14 000) rich in cysteine/half-cystine has been isolated from camel milk by exclusion chromatography and reverse-phase high-performance liquid chromatography. The N-terminal amino acid sequence shows a region with several positional identities with and -caseins, which however lack cysteine residues; postions 16–20 are identical and involve the serine residues that have been found to be phosphorylated in -caseins. 相似文献
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Ahsan Ullah Khan 《Luminescence》1995,10(6):329-333
Simple acidification of aqueous alkaline peroxynitrite quantitatively generates singlet (1Δg) molecular oxygen, detected and quantitated spectroscopically (1270 nm). This observation provides a chemical basis for physiological cytotoxicity of ONOO? generated in the diffusion - controlled reaction of cellular NO? and O. The experiments consist of (i) chemical generation of ONOO? from NO? gas and KO2 powder in alkaline aqueous solution; (ii) absorption spectral identification of ONOO? in the near-UV with maximum at 302 nm; (iii) spectroscopic identification of 1O2 by its emission band at 1200–1340 nm with maximum at 1275 nm; and (iv) quantitation of 1O2 generated in ONOO?/H+ reaction by comparison of the chemiluminescence intensity at 1270 nm with that from H2O2/OCl? reaction that generates 1O2 with unit efficiency at alkaline pH. 1O2 was generated with unit efficiency with respect to ONOO? concentration by the ONOO?/H+ reaction. 相似文献
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Irfan Farabi Hayat Manuel Plan Birgitta E. Ebert Geoff Dumsday Claudia E. Vickers Bingyin Peng 《Microbial biotechnology》2021,14(6):2627-2642
The yeast Saccharomyces cerevisiae uses the pyruvate dehydrogenase-bypass for acetyl-CoA biosynthesis. This relatively inefficient pathway limits production potential for acetyl-CoA-derived biochemical due to carbon loss and the cost of two high-energy phosphate bonds per molecule of acetyl-CoA. Here, we attempted to improve acetyl-CoA production efficiency by introducing heterologous acetylating aldehyde dehydrogenase and phosphoketolase pathways for acetyl-CoA synthesis to enhance production of the sesquiterpene trans-nerolidol. In addition, we introduced auxin-mediated degradation of the glucose-dependent repressor Mig1p to allow induced expression of GAL promoters on glucose so that production potential on glucose could be examined. The novel genes that we used to reconstruct the heterologous acetyl-CoA pathways did not sufficiently complement the loss of endogenous acetyl-CoA pathways, indicating that superior heterologous enzymes are necessary to establish fully functional synthetic acetyl-CoA pathways and properly explore their potential for nerolidol synthesis. Notwithstanding this, nerolidol production was improved twofold to a titre of ˜ 900 mg l−1 in flask cultivation using a combination of heterologous acetyl-CoA pathways and Mig1p degradation. Conditional Mig1p depletion is presented as a valuable strategy to improve the productivities in the strains engineered with GAL promoters-controlled pathways when growing on glucose. 相似文献
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Sher Hayat Khan Deming Zhao Syed Zahid Ali Shah Mohammad Farooque Hassan Ting Zhu Zhiqi Song Xiangmei Zhou Lifeng Yang 《Cellular and molecular neurobiology》2017,37(4):717-728
Transmissible spongiform encephalopathies (TSEs) are caused by the accumulation of the abnormal prion protein scrapie (PrPSc). Prion protein aggregation, misfolding, and cytotoxicity in the brain are the major causes of neuronal dysfunction and ultimate neurodegeneration in all TSEs. Parkin, an E3 ubiquitin ligase, has been studied extensively in all major protein misfolding aggregating diseases, especially Parkinson’s disease and Alzheimer’s disease, but the role of parkin in TSEs remains unknown. Here we investigated the role of parkin in a prion disease cell model in which neuroblastoma2a (N2a) cells were treated with prion peptide PrP106–126. We observed a gradual decrease in the soluble parkin level upon treatment with PrP106–126 in a time-dependent manner. Furthermore, endogenous parkin colocalized with FITC-tagged prion fragment106–126. Overexpression of parkin in N2a cells via transfection repressed apoptosis by enhancing autophagy. Parkin-overexpressing cells also showed reductions in apoptotic BAX translocation to the mitochondria and cytochrome c release to the cytosol, which ultimately inhibited activation of proapoptotic caspases. Taken together, our findings reveal a parkin-mediated cytoprotective mechanism against PrP106–126 toxicity, which is a novel potential therapeutic target for treating prion diseases. 相似文献
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This paper looks at the series solutions of three dimensional boundary layer flow. An Oldroyd-B fluid with variable thermal conductivity is considered. The flow is induced due to stretching of a surface. Analysis has been carried out in the presence of heat generation/absorption. Homotopy analysis is implemented in developing the series solutions to the governing flow and energy equations. Graphs are presented and discussed for various parameters of interest. Comparison of present study with the existing limiting solution is shown and examined. 相似文献