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61.
Mubasher Jamil D. Momeni Ratbay Myrzakulov 《International Journal of Theoretical Physics》2013,52(9):3283-3294
In this paper, we have calculated the statefinder parameters for the Friedmann-Robertson-Walker (FRW) Universe in the gravitational framework of loop quantum cosmology (LQC). As examples, we study two types of dark energy models namely Holographic dark energy and New-Agegraphic dark energy. 相似文献
62.
In this paper, the metric approach of f(R) theory of gravity is used to investigate the exact vacuum solutions of spatially homogeneous rotating spacetimes. For this purpose, R is replaced by f(R) in the standard Einstein-Hilbert action and the set of modified Einstein field equations reduce to a single equation. We adopt the assumption of constant Ricci scalar which maybe zero or non-zero. Moreover, the energy density of the non-trivial solution has been evaluated by using the generalized Landau-Lifshitz energy-momentum complex in the perspective of f(R) gravity for some appropriate f(R) model, which turns out to be a constant quantity. 相似文献
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65.
Hossain M. A. Siddiki S. M. A. Hakim Elias M. Rahman M. M. Jamil M. A. R. 《Russian Journal of Organic Chemistry》2020,56(10):1806-1814
Russian Journal of Organic Chemistry - Methods have been reported for the preparation of ω-functionalized alkyl maltoside and glycoside detergents via a simple and inexpensive synthetic route.... 相似文献
66.
Dr. Muhammad Ehsan Dr. Yang Du Jonas S. Mortensen Dr. Parameswaran Hariharan Qianhui Qu Lubna Ghani Dr. Manabendra Das Anne Grethen Prof. Bernadette Byrne Prof. Georgios Skiniotis Prof. Sandro Keller Prof. Claus J. Loland Prof. Lan Guan Prof. Brian K. Kobilka Prof. Pil Seok Chae 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(49):11545-11554
Amphipathic agents are widely used in various fields including biomedical sciences. Micelle-forming detergents are particularly useful for in vitro membrane-protein characterization. As many conventional detergents are limited in their ability to stabilize membrane proteins, it is necessary to develop novel detergents to facilitate membrane-protein research. In the current study, we developed novel trimaltoside detergents with an alkyl pendant-bearing terphenyl unit as a hydrophobic group, designated terphenyl-cored maltosides (TPMs). We found that the geometry of the detergent hydrophobic group substantially impacts detergent self-assembly behavior, as well as detergent efficacy for membrane-protein stabilization. TPM-Vs, with a bent terphenyl group, were superior to the linear counterparts (TPM-Ls) at stabilizing multiple membrane proteins. The favorable protein stabilization efficacy of these bent TPMs is likely associated with a binding mode with membrane proteins distinct from conventional detergents and facial amphiphiles. When compared to n-dodecyl-β-d -maltoside (DDM), most TPMs were superior or comparable to this gold standard detergent at stabilizing membrane proteins. Notably, TPM-L3 was particularly effective at stabilizing the human β2 adrenergic receptor (β2AR), a G-protein coupled receptor, and its complex with Gs protein. Thus, the current study not only provides novel detergent tools that are useful for membrane-protein study, but also suggests a critical role for detergent hydrophobic group geometry in governing detergent efficacy. 相似文献
67.
Nabil N. AL‐Hashimi Rand O. Shahin Aqeel N. AL‐Hashimi Ajeal M. Al Ajeal Lubna H. Tahtamouni Chanbasha Basheer 《Biomedical chromatography : BMC》2019,33(2)
A new cetyl‐alcohol‐reinforced hollow fiber solid/liquid‐phase microextraction (CA–HF–SLPME) followed by high‐performance liquid chromatography–diode array detection (HPLC–DAD) method was developed for simultaneous determination of ezetimibe and simvastatin in human plasma and urine samples. To prepare the CA–HF–SLPME device, the cetyl‐alcohol was immobilized into the pores of a 2.5 cm hollow fiber micro‐tube and the lumen of the micro‐tube was filled with 1‐octanol with the two ends sealed. Afterwards, the prepared device was introduced into 10 mL of the sample solution containing the analytes with agitation. Under optimized conditions, calibration curves plotted in spiked plasma and urine samples were linear in the ranges of 0.363–25/0.49–25 μg L?1 for ezetimibe/simvastatin and 0.193–25/0.312–25 μg L?1 for ezetimibe/simvastatin in plasma and urine samples, respectively. The limit of detection was 0.109/0.174 μg L?1 for ezetimibe/simvastatin in plasma and 0.058/0.093 μg L?1 for ezetimibe/simvastatin in urine. As a potential application, the proposed method was applied to determine the concentration of selected analytes in patient plasma and urine samples after medication and satisfactory results were achieved. In comparison with reference methods, the CA–HF–SLPME–HPLC–DAD method demonstrates considerable potential in the biopharmaceutical analysis of selected drugs. 相似文献
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69.
Mazhar-ul-Haque Hasan A. Tayim Jamil Ahmed William Horne 《Journal of chemical crystallography》1985,15(6):561-571
Triphenylarsine crystallizes in the triclinic space groupP¯1 (No. 2),a=11.200(2),b=15.263(7),c=17.871(6) Å,=84.63(5),=80.21(5), =86.41(6)°,Z=8, with four molecules in the asymmetric unit. The structure was solved by direct methods and refined in the initial stages by full-matrix least squares and finally by block-diagonal least-squares methods toR=0.055 for 3537 reflections. The dimensions and the conformations of the four independent molecules are almost identical. The molecules do not exhibitC
3v
symmetry. 相似文献
70.
Mazhar-ul-Haque Patrick Pollet Jamil Ahmed William Horne 《Journal of chemical crystallography》1984,14(5):495-503
The title compound crystallizes in the monoclinic space groupP21/n (No. 14),a=14.923(2),b=4.165(2),c=18.097(2) Å,=106.40(1)°,Z=4. The structure was solved by direct methods, and refined by full-matrix least squares toR=0.048 for 1313 observed reflections. Inter- and intramolecular hydrogen bonding is observed, the latter resulting in the formation of dimers. 相似文献