排序方式: 共有50条查询结果,搜索用时 31 毫秒
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Abdur Rauf Tareq Abu-Izneid Anees Ahmed Khalil Muhammad Imran Zafar Ali Shah Talha Bin Emran Saikat Mitra Zidan Khan Fahad A. Alhumaydhi Abdullah S. M. Aljohani Ishaq Khan Md. Mominur Rahman Philippe Jeandet Tanweer Aslam Gondal 《Molecules (Basel, Switzerland)》2021,26(23)
Berberine (BBR), a potential bioactive agent, has remarkable health benefits. A substantial amount of research has been conducted to date to establish the anticancer potential of BBR. The present review consolidates salient information concerning the promising anticancer activity of this compound. The therapeutic efficacy of BBR has been reported in several studies regarding colon, breast, pancreatic, liver, oral, bone, cutaneous, prostate, intestine, and thyroid cancers. BBR prevents cancer cell proliferation by inducing apoptosis and controlling the cell cycle as well as autophagy. BBR also hinders tumor cell invasion and metastasis by down-regulating metastasis-related proteins. Moreover, BBR is also beneficial in the early stages of cancer development by lowering epithelial–mesenchymal transition protein expression. Despite its significance as a potentially promising drug candidate, there are currently no pure berberine preparations approved to treat specific ailments. Hence, this review highlights our current comprehensive knowledge of sources, extraction methods, pharmacokinetic, and pharmacodynamic profiles of berberine, as well as the proposed mechanisms of action associated with its anticancer potential. The information presented here will help provide a baseline for researchers, scientists, and drug developers regarding the use of berberine as a promising candidate in treating different types of cancers. 相似文献
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Syamsuri Yaakob Muhammad Zamzuri Abdul Kadir Sevia Mahdaliza Idrus Norhakimah Md Samsuri Romli Mohamad Nazif Emran Farid 《Optik》2013
The dual sideband optical carrier suppression (DSB-OCS) technique is employed in the optical carrier generation for 40 GHz radio over fiber (ROF) system. A dual electrode Mach-Zehnder modulator (DE-MZM) with the minimum transmission bias (MiTB) technique is employed to build the system. The results show that, a 40 GHz carrier is successfully generated with the amplitude up to −29 dBm and signal to noise ratio (SNR) of 35 dB and a high definition (HD) signal is successfully transmitted using the system. Finally, the bit error rate (BER) measurement is carried out for the system with 1.25 Gbps OOK signal showing an error free 40 GHz ROF system with almost no penalty between the back to back and 20 km fiber for a BER of 10−9. 相似文献
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This work deals with a study of the vibrational properties of functionally graded nanocomposite beams reinforced by randomly oriented straight single-walled carbon nanotubes (SWCNTs) under the actions of moving load. Timoshenko and Euler-Bernoulli beam theories are used to evaluate dynamic characteristics of the beam. The Eshelby-Mori-Tanaka approach based on an equivalent fiber is used to investigate the material properties of the beam. An embedded carbon nanotube in a polymer matrix and its surrounding inter-phase is replaced with an equivalent fiber for predicting the mechanical properties of the carbon nanotube/polymer composite. The primary contribution of the present work deals with the global elastic properties of nano-structured composite beams. The system of equations of motion is derived by using Hamilton’s principle under the assumptions of the Timoshenko beam theory. The finite element method is employed to discretize the model and obtain a numerical approximation of the motion equation. In order to evaluate time response of the system, Newmark method is also used. Numerical results are presented in both tabular and graphical forms to figure out the effects of various material distributions, carbon nanotube orientations, velocity of the moving load, shear deformation, slenderness ratios and boundary conditions on the dynamic characteristics of the beam. The results show that the above mentioned effects play very important role on the dynamic behavior of the beam and it is believed that new results are presented for dynamics of FG nano-structure beams under moving loads which are of interest to the scientific and engineering community in the area of FGM nano-structures. 相似文献
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A combination of ultrasound and inorganic catalyst: removal of 2-chlorophenol from aqueous solution 总被引:2,自引:0,他引:2
Removal of 2-chlorophenol by ultrasonic waves (sonolysis), inorganic catalyst, and a combination of the two processes was tested and compared with each technique. In sonolysis, 2-chlorophenol mostly degraded indirectly in the bulk of solution by the radicals produced in the cavitation process. In catalyst treatment, the removal was performed in the presence of Al2O3, TiO2 and CuO. The highest removal was achieved in the presence of TiO2 for this pollutant. In the combined method an enhancement was observed for the removal of 2-chlorophenol. This could be attributed primarily to the continuous cleaning and chemical activation of the catalyst by acoustic cavitation. The mass transfer between the liquid phase and the catalyst and also the surface area of the catalyst are accelerated by the ultrasonic waves. The removal of 2-chlorophenol was performed under different intensities of irradiation, temperatures and quantities of catalyst. Some experiments were conducted in the presence of a Fenton reagent. In kinetic point of view, the removal of pollutant showed a pseudo-first order behavior. The combined method had a higher rate coefficient than sonolysis and catalyst treatment individually. Under some conditions, the presence of ultrasound has increased the rate coefficient of removal to about 10 times that in the absence of ultrasound. 相似文献
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M. A. Jafarizadeh M. Mahdian A. Heshmati K. Aghayar 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,50(1):107-121
The three qubits mutually unbiased bases (MUB) diagonal density matrices with maximally entanglement in Greenberger-Horne-Zeilinger
(GHZ) basis are studied. These are a natural generalization of Bell-state diagonal density matrices. The linearity of positive
partial transpose (PPT) conditions allows one to specify completely PPT states or feasible region (FR) which form a polygon,
where the projection of the feasible region to some two dimensional planes has lead to better visualization. To reveal the
PPT entangled regions of these density matrices, we manipulate some appropriate optimal non-decomposable linear entanglement
witnesses (EWs) as the envelope of family of linear optimal non-decomposable EWs. These nonlinear EWs are nonlinear functional
of MUB diagonal states, so that they are nonnegative valued over all separable, but they are negative valued over some PPT
entangled MUB diagonal states. Even though, these nonlinear EWs can not separate completely, the PPT entanglement region from
separable one, but however in special cases they lead to necessary and sufficient condition for separability. To support the
evidence, we study three categories for special choices of parameters in density matrices, and using the nonlinear EWs we
can distinguish the region of PPT entangled states and separable states, completely. At the end some numerical simulations
are provided to show the practical applicability of these nonlinear EWs in detecting some PPT entangled MUB diagonal states. 相似文献
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Trina Ekawati Tallei Fatimawali Ahmad Akroman Adam Mona M. Elseehy Ahmed M. El-Shehawi Eman A. Mahmoud Adinda Dwi Tania Nurdjannah Jane Niode Diah Kusumawaty Souvia Rahimah Yunus Effendi Rinaldi Idroes Ismail Celik Md. Jamal Hossain Talha Bin Emran 《Molecules (Basel, Switzerland)》2022,27(1)
Before entering the cell, the SARS-CoV-2 spike glycoprotein receptor-binding domain (RBD) binds to the human angiotensin-converting enzyme 2 (hACE2) receptor. Hence, this RBD is a critical target for the development of antiviral agents. Recent studies have discovered that SARS-CoV-2 variants with mutations in the RBD have spread globally. The purpose of this in silico study was to determine the potential of a fruit bromelain-derived peptide. DYGAVNEVK. to inhibit the entry of various SARS-CoV-2 variants into human cells by targeting the hACE binding site within the RBD. Molecular docking analysis revealed that DYGAVNEVK interacts with several critical RBD binding residues responsible for the adhesion of the RBD to hACE2. Moreover, 100 ns MD simulations revealed stable interactions between DYGAVNEVK and RBD variants derived from the trajectory of root-mean-square deviation (RMSD), radius of gyration (Rg), and root-mean-square fluctuation (RMSF) analysis, as well as free binding energy calculations. Overall, our computational results indicate that DYGAVNEVK warrants further investigation as a candidate for preventing SARS-CoV-2 due to its interaction with the RBD of SARS-CoV-2 variants. 相似文献