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Donovan Callahan posted an update 11 hours, 28 minutes ago
Ultimately, this study serves as a good contribution to update the existing knowledge on the anticancer organophosphorus heterocyclic compounds and elevates the scope for generation of new anticancer drugs. Further, the studies like QSAR, drug properties, toxicity risks, and bioactivity scores predicted for them have ascertained the synthesized compounds as newer and potential drug candidates. Hence, this study had augmented the array of α-aminophosphonates by adding a new collection of 3-amino-2-hydroxybenzofused 2-phosphalactones, a class of cyclic α-aminophosphonates, to it, which proved them as potential anti-pancreatic cancer agents.Protein kinase R (PKR) is a key pattern recognition receptor of the innate immune pathway. PKR is activated by double-stranded RNA (dsRNA) that is often produced during viral genome replication and transcription. PKR contains two tandem double-stranded RNA binding domains at the N-terminus, dsRBD1 and dsRBD2, and a C-terminal kinase domain. In the canonical model for activation, RNAs that bind multiple PKRs induce dimerization of the kinase domain that promotes an active conformation. However, there is evidence that dimerization of the kinase domain is not sufficient to mediate activation and PKR activation is modulated by the RNA-binding mode. dsRBD2 lacks most of the consensus RNA-binding residues, and it has been suggested to function as a modulator of PKR activation. Here, we demonstrate that dsRBD2 regulates PKR activation and identify the N-terminal helix as a critical region for modulating kinase activity. Mutations in dsRBD2 that have minor effects on overall dsRNA-binding affinity strongly inhibit the activation of PKR by dsRNA. These mutations also inhibit RNA-independent PKR activation. These data support a model where dsRBD2 has evolved to function as a regulator of the kinase.The design and optimization of solvent extraction processes for metal separations are challenging tasks due to the large number of adjustable parameters. A quantitative predictive solvent extraction model could help to determine the optimal parameters for solvent extraction flow sheets, but such predictive models are not available yet. The main difficulties for such models are the large deviations from ideal thermodynamic behavior in both the aqueous and organic phases due to high solute concentrations. We constructed a molecular thermodynamic model for the extraction of CoCl2 from different chloride salts by 0.2 mol L-1 trioctylmethylammonium chloride in toluene using the OLI mixed-solvent electrolyte (OLI-MSE) framework. This was accomplished by analyzing the water and hydrochloric acid content of the organic phase, measuring the water activity of the system, and using metal complex speciation and solvent extraction data. The full extractant concentration range cannot be modeled by the OLI-MSE framework as this framework lacks a description for reversed micelle formation. Nevertheless, salting effects and the behavior of hydrochloric acid can be accurately described with the presented extraction model, without determining specific Co(II)-salt cation interaction parameters. The resulting model shows that the salting effects originate from indirect salt cation-solvent interactions that influence the availability of water in the aqueous and organic phases.This paper reported a dry synthesis and characterization of cerium tetrafluoride (CeF4) and cerium trifluoride (CeF3) nanoscale polycrystals (NPs). see more The CeF4 NPs were spherical or flaky and approximately 10 ± 2 nm in diameter. The CeF3 NPs were rod-shaped nanorods with a length of about 150 ± 5 nm and a diameter of about 20 ± 2 nm. The first step was to synthesize the intermediate product-(NH4)4CeF8 by mixing CeO2 and NH4HF2 at a molar ratio of 16 at 390 K. The structural characterization was analyzed by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Then, (NH4)4CeF8 was heated in an argon gas flow to synthesize the CeF3 and CeF4 NPs. The products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The properties of CeF3 and CeF4 NPs were further evaluated by transmission electron microscopy (TEM), selected area electron diffraction pattern (SAED), and high-resolution transmission electron microscopy (HRTEM). The findings provided an alternative strategy for the synthesis of nanometer fluorides, which could be a reference for high-performance research on other nanometer fluorides.Herein, we describe for the first time, the design and fabrication of a novel nicotine paper-based sensor, in which a miniaturized paper reference electrode is integrated for potentiometric measurements. The paper-based sensors were designed using printed wax barriers to define the electrochemical cell and the sample zones. The electrodes were based on the use of the ion association complexes of the nicotinium cation (Nic) with either tetraphenylborate (TPB) or 5-nitrobarbiturate (NB) counter anions as sensing materials for nicotine recognition. A poly (3,4 ethylenedioxythiophene)/poly-(styrene sulfonate) (PEDOT/PSS) conducting polymer was used as an ion-to-electron transducer. The performance characteristics of the proposed sensors were evaluated and it revealed a rapid and stable response with a Nernstian slope of 55.2 ± 0.3 and 51.2 ± 0.6 mV/decade over the linear range of 1.0 × 10-5 to 1.0 × 10-2 M and detection limits of 6.0 and 8.0 μM for [Nic/TPB] and [Nic/NB], respectively. The sensors revealed a constant response over the pH range 3.5-6.5. The designed sensors provided a portable, inexpensive, and disposable way of measuring trace levels of nicotine coming from different cigarettes and in the collected human sweat of heavy smokers. All results were compared favorably with those obtained by the standard gas chromatographic method.Surfactant polymer flooding is one of the most common chemical enhanced oil recovery techniques, which improves not only the microscopic displacement of the fluid through the formation of the emulsion but also the volumetric sweep efficiency of the fluid by altering the viscosity of the displacing fluid. However, one constraint of surfactant flooding is the loss of the surfactant by adsorption onto the reservoir rock surface. Hence, in this study, an attempt has been made to reduce the adsorption of the surfactant on the rock surface using novel colloidal silica nanoparticles (CSNs). CSNs were used as an additive to improve the performance of the conventional surfactant polymer flooding. The reduction in adsorption was observed in both the presence and absence of a polymer. The presence of a polymer also reduced the adsorption of the surfactant. Addition of 25 vol % CSNs effectively reduced the adsorption of up to 61% in the absence of a polymer, which increased to 64% upon the introduction of 1000 ppm polymer in the solution at 2500 ppm of the surfactant concentration at 25 °C.