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51.
This paper introduces and studies a new generalization of cumulative past extropy called weighted cumulative past extropy (WCPJ) for continuous random variables. We explore the following: if the WCPJs of the last order statistic are equal for two distributions, then these two distributions will be equal. We examine some properties of the WCPJ, and a number of inequalities involving bounds for WCPJ are obtained. Studies related to reliability theory are discussed. Finally, the empirical version of the WCPJ is considered, and a test statistic is proposed. The critical cutoff points of the test statistic are computed numerically. Then, the power of this test is compared to a number of alternative approaches. In some situations, its power is superior to the rest, and in some other settings, it is somewhat weaker than the others. The simulation study shows that the use of this test statistic can be satisfactory with due attention to its simple form and the rich information content behind it. 相似文献
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53.
Shafia Shafiq Ronok Zahan Samina Yesmin Alam Khan Md. Sabbir Mahmud Md Abu Reza Sarah M. Albogami Mohammed Alorabi Michel De Waard Hebatallah M. Saad Jean-Marc Sabatier Tarannum Naz Gaber El-Saber Batiha 《Molecules (Basel, Switzerland)》2022,27(20)
Litsea glutinosa (L. glutinosa) is considered an evidence-based medicinal plant for the treatment of cancer, the leading cause of death worldwide. In our study, the in vitro antioxidant and in vivo anticancer properties of an essential ethno-medicinal plant, L. glutinosa, were examined using non-toxic doses and a phytochemical analysis was executed using gas-chromatography–mass-spectrometry. The in vitro antioxidant study of the L. glutinosa methanolic extract (LGBME) revealed a concentration-dependent antioxidant property. The bark extract showed promising antioxidant effects in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay. The strongest antioxidant activity was demonstrated at the maximum concentration (50 µg/mL). The IC50 values of the LGBME and BHT were 5.51 and 5.01 µg/mL, respectively. At the same concentration, the total antioxidant capacity of the LGBME was 0.161 µg/mL and the ferric reducing antioxidant power assay result of the LGBME was 1.783 µg/mL. In the cytotoxicity study, the LD50 of the LGBME and gallic acid were 24.93 µg/mL and 7.23 µg/mL, respectively. In the in vivo anticancer-activity studies, the LGBME, particularly at a dose of 150 mg/kg/bw, showed significant cell-growth inhibition, decreased tumor weight, increased mean survival rate, and upregulated the reduced hematological parameters in EAC (Ehrlich’s ascites carcinoma)-induced Swiss albino mice. The highest cell-growth inhibition, 85.76%, was observed with the dose of 150 mg/kg/bw. Furthermore, the upregulation of pro-apoptotic genes (p53, Bax) and the downregulation of anti-apoptotic Bcl-2 were observed. In conclusion, LGBME extract has several bioactive phytoconstituents, which confirms the antioxidant and anticancer properties of L. glutinosa. 相似文献
54.
Yi-Dan Zheng Li-Mei Ma Jin-Jian Lu Tian Chai Mohammad Reza Naghavi Jun-Yi Ma Chun-Yan Sang Jun-Li Yang 《Molecules (Basel, Switzerland)》2022,27(20)
Pancreatic cancer is the seventh leading cause of cancer-related death worldwide and is known as “the king of cancers”. Currently, gemcitabine (GEM) as the clinical drug of choice for chemotherapy of advanced pancreatic cancer has poor drug sensitivity and ineffective chemotherapy. Nardoguaianone L (G-6) is a novel guaiane-type sesquiterpenoid isolated from Nardostachys jatamansi DC., and it exhibits anti-tumor activity. Based on the newly discovered G-6 with anti-pancreatic cancer activity in our laboratory, this paper aimed to evaluate the potential value of the combination of G-6 and GEM in SW1990 cells, including cell viability, cell apoptosis, colony assay and tandem mass tags (TMT) marker-based proteomic technology. These results showed that G-6 combined with GEM significantly inhibited cell viability, and the effect was more obvious than that with single drug. In addition, the use of TMT marker-based proteomic technology demonstrated that the AGE-RAGE signaling pathway was activated after medication-combination. Furthermore, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) assays were used to validate the proteomic results. Finally, apoptosis was detected by flow cytometry. In conclusion, G-6 combined with GEM induced an increase in ROS level and a decrease in MMP in SW1990 cells through the AGE-RAGE signaling pathway, ultimately leading to apoptosis. G-6 improved the effect of GEM chemotherapy and may be used as a potential combination therapy for pancreatic cancer. 相似文献
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Hashemi Karouei Seyed Hossein Ajarostaghi Seyed Soheil Mousavi Gorji-Bandpy Mofid Hosseini Fard Seyed Reza 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1455-1466
Journal of Thermal Analysis and Calorimetry - In the present study, the effect of inserting an innovative curved turbulator and utilizing two types of hybrid nanofluids on thermal performance in a... 相似文献
57.
Mohammad Baghery Mahmoudian Ali Reza Nejad Ahmad Iran 《Russian Journal of Electrochemistry》2021,57(6):567-579
Russian Journal of Electrochemistry - Zinc selenide has applications in the fabrication of low-cost solar cells and optoelectronic devices. Due to its optical properties and large direct bandgap,... 相似文献
58.
Biabangard Fatemeh Nazari Hadiseh Arefinia Reza 《Journal of Solid State Electrochemistry》2021,25(3):881-893
Journal of Solid State Electrochemistry - A stable suspension of nanopolyaniline (nPANI) particles can be used in various applications instead of a polyaniline film. The electrochemical behavior of... 相似文献
59.
Nowadays, pharmaceutical antibiotics are known as a serious class of pollutants. Therefore, it is important to develop effective methods for removing these pollutants from aqueous media. Different methods were applied for this purpose, and among these methods, chemical reduction by a cheap and eco‐friendly nanocatalyst is the most efficient and simplest method. In this research, based on graphene oxide supported by zero‐valent iron in mono‐, bi‐, and tri‐metallic systems, various nanocomposites were synthesized and used to degrade tetracycline as a model antibiotic from aqueous media. An investigation was carried out on the synergic effect among graphene oxide and the nano zero‐valent iron‐based tri‐metallic system as well as removal efficiencies. It was found that higher degradation efficiency is yielded by graphene oxide supported by Fe/Cu/Ag tri‐metallic system. The maximum synergic effect occurs at an acidic medium. The Brunauer–Emmett–Teller, Fourier transform spectroscopy, scanning electron microscopy‐energy dispersive X‐ray analysis, transmission electron microscopy, and X‐ray diffraction analysis were used to characterize the synthesized nanocomposites, which has successfully proved the loading of nanoscale Fe/Cu/Ag tri‐metallic on a graphene oxide support. The central composite design was used to model and optimize all involved variables affecting antibiotic removal efficiency. The consequences illustrated the optimum condition regarding the removal of 50 ppm of tetracycline, for the nanocomposites dose of 3.0 mg ml?1, the contact time of 30 min, and pH of 2, was achieved using the simplex non‐linear optimization method. Moreover, antibiotic adsorption kinetic models were also investigated. Finally, the tetracycline removal from aqueous media at different concentrations, 25, 50, and 75 ppm, was successful by applying the proposed nanocomposite, and the results showed tetracycline removal efficiencies of above 70%. 相似文献
60.
Maryam S. Sadeghi Mohammad Reza Moghbeli William A. Goddard III 《Journal of polymer science. Part A, Polymer chemistry》2021,59(7):614-626
We followed the self-assembly of high-molecular weight MePEG- b -PCL (poly(methyl ethylene glycol)-block-poly(ε-caprolactone)) diblock and MePEG- b -PBO- b -PCL (poly(methyl ethylene glycol)-block-poly(1,2-butylene oxide)-block-poly(ε-caprolactone)) into micelles using molecular dynamics simulation with a coarse grain (CG) force field based on quantum mechanics (CGq FF). The triblock polymer included a short poly(1,2-butylene oxide) (PBO) at the hydrophilic-hydrophobic interface of these systems. Keeping the hydrophilic length fixed (MePEG45), we considered 250 chains in which the hydrophobic length changed from PCL44 or PBO6- b -PCL43 to PCL62 or PBO9- b -PCL61. The polymers were solvated in explicit water for 2 μs of simulations at 310.15 K. We found that the longer diblock system undergoes a morphological transition from an intermediate rod-like micelle to a prolate-sphere, while the micelle formed from the longer triblock system is a stable rod-like micelle. The two shorter diblock and triblock systems show similar self-assembly processes, both resulting in slightly prolate-spheres. The dynamics of the self-assembly is quantified in terms of chain radius of gyration, shape anisotropy, and hydration of the micelle cores. The final micelle structures are analyzed in terms of the local density components. We conclude that the CG model accurately describes the molecular mechanisms of self-assembly and the equilibrium micellar structures of hydrophilic and hydrophobic chains, including the quantity of solvent trapped inside the micellar core. 相似文献