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381.
382.
A systematic variation of shape variables \(\beta \) and \(\gamma \) with N and \(N_\mathrm {p}N_\mathrm {n}\) is studied in the framework of an asymmetric rotor model of Davydov and Filippov for the \(Z=\) 50–82, \(N=\) 82–126 major shell space. The role of the \(Z=64\) subshell in producing smooth systematics has been discussed. The quadrupole moments are extracted after considering both axially symmetric and axially asymmetric nuclei. The correlation of \(\beta \) with \(\gamma \) together with the measured quadrupole moments indicates that \(\gamma \)-rigidity is better observed in nuclei with modest deformation.  相似文献   
383.
Onosma bracteata Wall. is an important medicinal and immunity-enhancing herbs. This plant is commonly used in the preparation of traditional Ayurvedic drugs to treat numerous diseases. Inspired by the medicinal properties of this plant, the present study aimed to investigate the antiproliferative potential and the primary molecular mechanisms of the apoptotic induction against human osteosarcoma (MG-63) cells. Among all the fractions isolated from O. bracteata, ethyl acetate fraction (Obea) showed good antioxidant activity in superoxide radical scavenging assay and lipid peroxidation assay with an EC50 value of 95.12 and 80.67 µg/mL, respectively. Silica gel column chromatography of ethyl acetate (Obea) fraction of O. bracteata yielded a pure compound, which was characterized by NMR, FTIR, and HR-MS analysis and was identified as 1,2-benzene dicarboxylic acid, bis (2-methyl propyl) ester (BDCe fraction). BDCe fraction was evaluated for the antiproliferative potential against human osteosarcoma MG-63, human neuroblastoma IMR-32, and human lung carcinoma A549 cell lines by MTT assay and exhibited GI50 values of 37.53 μM, 56.05 μM, and 47.12 μM, respectively. In MG-63 cells, the BDCe fraction increased the level of ROS and simultaneously decreased the mitochondria membrane potential (MMP) potential by arresting cells at the G0/G1 phase, suggesting the initiation of apoptosis. Western blotting analysis revealed the upregulation of p53, caspase3, and caspase9 while the expressions of p-NF-κB, p-Akt and Bcl-xl were decreased. RT-qPCR studies also showed upregulation in the expression of p53 and caspase3 and downregulation in the expression of CDK2, Bcl-2 and Cyclin E genes. Molecular docking analysis displayed the interaction between BDCe fraction with p53 (−151.13 kcal/mol) and CDK1 (−133.96 kcal/mol). The results of the present work suggest that the BDCe fraction has chemopreventive properties against osteosarcoma (MG-63) cells through the induction of cell cycle arrest and apoptosis via Akt/NF-κB/p53 pathways. This study contributes to the understanding of the utilization of BDCe fraction in osteosarcoma treatment.  相似文献   
384.
The single alpha helix (SAH) is a recurring motif in biology. The consensus sequence has a di-block architecture that includes repeats of four consecutive glutamate residues followed by four consecutive lysine residues. Measurements show that the overall helicity of sequences with consensus E4K4 repeats is insensitive to a wide range of pH values. Here, we use the recently introduced q-canonical ensemble, which allows us to decouple measurements of charge state and conformation, to explain the observed insensitivity of SAH helicity to pH. We couple the outputs from separate measurements of charge and conformation with atomistic simulations to derive residue-specific quantifications of preferences for being in an alpha helix and for the ionizable residues to be charged vs. uncharged. We find a clear preference for accommodating uncharged Glu residues within internal positions of SAH-forming sequences. The stabilities of alpha helical conformations increase with the number of E4K4 repeats and so do the numbers of accessible charge states that are compatible with forming conformations of high helical content. There is conformational buffering whereby charge state heterogeneity buffers against large-scale conformational changes thus making the overall helicity insensitive to large changes in pH. Further, the results clearly argue against a single, rod-like alpha helical conformation being the only or even dominant conformation in the ensembles of so-called SAH sequences.  相似文献   
385.
Rechargeable sodium-ion batteries (SIBs) are emerging as a viable alternative to lithium-ion battery (LIB) technology, as their raw materials are economical, geographically abundant (unlike lithium), and less toxic. The matured LIB technology contributes significantly to digital civilization, from mobile electronic devices to zero electric-vehicle emissions. However, with the increasing reliance on renewable energy sources and the anticipated integration of high-energy-density batteries into the grid, concerns have arisen regarding the sustainability of lithium due to its limited availability and consequent price escalations. In this context, SIBs have gained attention as a potential energy storage alternative, benefiting from the abundance of sodium and sharing electrochemical characteristics similar to LIBs. Furthermore, high-entropy chemistry has emerged as a new paradigm, promising to enhance energy density and accelerate advancements in battery technology to meet the growing energy demands. This review uncovers the fundamentals, current progress, and the views on the future of SIB technologies, with a discussion focused on the design of novel materials. The crucial factors, such as morphology, crystal defects, and doping, that can tune electrochemistry, which should inspire young researchers in battery technology to identify and work on challenging research problems, are also reviewed.  相似文献   
386.
Demands for effective high-temperature electrical conductors continue to increase with the rapid adoption of electric vehicles. However, the use of conventional copper-based conductors is limited to relatively low temperatures due to their poor oxidation resistance and microstructural instability. Here, a highly conductive and thermally stable nickel-graphene-copper (NiGCu) wire that combines the advantages of graphene and its metallic components is developed. The NiGCu wire consists of a conductive copper core, an oxidation-resistant nickel shell, and axially continuous graphene embedded between them. The experiments on 10–80 µm diameter NiGCu wires demonstrate substantial enhancements in electrical properties and thermal stability across a variety of metrics. For instance, the smallest NiGCu wires have a 61.2% higher current density limit, 307.6% higher conductivity, and an order of magnitude smaller change in resistivity compared to conventional Ni-coated Cu counterparts after annealing at 650 °C. By performing both innovative experiments and simulations using different sizes of NiGCu wires, the diffusion coefficients of metals are quantified, for the first time to the best knowledge, through continuous graphene. These results indicate that the dramatic improvement in thermo-electrical properties is enabled by the embedded graphene layer which reduces Ni Cu interdiffusion by ≈104 times at 550 °C and 650 °C.  相似文献   
387.
The aim of this work is to identify numerically, for the first time, the time-dependent potential coefficient in a fourth-order pseudo-parabolic equation with nonlocal initial data, nonlocal boundary conditions, and the boundary data as overdetermination condition. This problem emerges significantly in the modeling of various phenomena in physics and engineering. From literature we already know that this inverse problem has a unique solution. However, the problem is still ill-posed by being unstable to noise in the input data. For the numerical realization, we apply the quintic B-spline (QB-spline) collocation method for discretizing the pseudo-parabolic problem and the Tikhonov regularization for finding a stable and accurate solution. The resulting nonlinear minimization problem is solved using the MATLAB subroutine lsqnonlin. Moreover, the von Neumann stability analysis is also discussed.  相似文献   
388.
Bioelectrocatalytic synthesis is the conversion of electrical energy into value-added products using biocatalysts. These methods merge the specificity and selectivity of biocatalysis and energy-related electrocatalysis to address challenges in the sustainable synthesis of pharmaceuticals, commodity chemicals, fuels, feedstocks and fertilizers. However, the specialized experimental setups and domain knowledge for bioelectrocatalysis pose a significant barrier to adoption. This review introduces key concepts of bioelectrosynthetic systems. We provide a tutorial on the methods of biocatalyst utilization, the setup of bioelectrosynthetic cells, and the analytical methods for assessing bioelectrocatalysts. Key applications of bioelectrosynthesis in ammonia production and small-molecule synthesis are outlined for both enzymatic and microbial systems. This review serves as a necessary introduction and resource for the non-specialist interested in bioelectrosynthetic research.  相似文献   
389.
The evolution of intelligent and data-driven systems has pushed for the tectonic transition from ancient medication to human-centric Healthcare 4.0. The rise of Internet of Things, Internet of Systems, and wireless body area networks has endowed the health care ecosystem with a new digital transformation supported by sophisticated machine learning and artificial intelligence algorithms. Under this umbrella, health care recommendation systems have emerged as a driver for providing patient-centric personalized health care services. Recommendation systems are automatic systems that derive the decisions on the basis of some valid input parameters and vital health information collected through wearable devices, implantable equipments, and various sensor. Therefore, to understand the state-of-the-art developments in the health care ecosystem, this paper provides a comprehensive survey on health care recommendation systems and the associated paradigms. This survey starts from the ancient health care era and move toward the Healthcare 4.0 in a phased manner. The road map from Healthcare 1.0 to Healthcare 4.0 is analyzed to highlight different technology verticals supporting the digital transformation. This study also provides the systematic review of the health care systems, the types of health care systems, and the recommender systems. Moreover, a deep analysis of health care recommender systems and its types is also presented. Finally, the open issues and challenges associated with the adaption and implementation of human-centric Healthcare 4.0 ecosystem are discussed. This is provided to find out the possible research questions and gaps so that the corresponding solutions could be developed in the near future.  相似文献   
390.
The present study describes forced degradation of benidipine (BEN) as per  Q1A (R2) and Q1B guidelines of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. BEN degraded under hydrolysis (neutral, acidic, and alkaline), hydrogen peroxide induced oxidation, and UV light mediated photolytic degradation. A total of 14 degradation products (DPs) were found in all degradation studies, comprising 4 hydrolytic DPs, 8 oxidative DPs, and 4 photolytic DPs. A selective stability-indicating method was developed using an XBridge BEH C18 column with gradient elution program consisting of ammonium acetate (10 mM, 4.8 pH, acetic acid) and acetonitrile. The flow rate was maintained at 1 ml min−1. All DPs were separated well using the developed HPLC method and were characterized using LC–MS/MS data. As this method is effective in identifying and separating BEN and its DPs with sufficient resolution, it can be used in laboratories for quality control of drugs in daily routine analysis and stability studies.  相似文献   
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