Davispaulsen1867
Dissipative particle dynamics (DPD) simulations has been performed to study the phase transition of a mixture of cationic and anionic surfactants in an aqueous solution as a function of the total concentration in water and the relative ratio of surfactants. The impact of the relative difference between the tail lengths of the cationic and anionic surfactants on the phase diagram has been simulated by tuning the number of DPD beads in the simulation model. This research also discusses the impact of the frequently used values of the parameters associated with the harmonic bonds among the bonded DPD beads on the obtained self-assemblies. We find remarkable differences in the resultant self-assemblies based on different choices of harmonic bond parameters. The performed simulations show an enhanced spectrum of self-assemblies with augmented tail lengths and disparate harmonic bond parameters. The obtained self-assemblies are quite unique and can potentially be used in the future for various applications. We also compare the simulation results of the vesicle structures obtained by modeling the electrostatic interaction in the simulation among the charged beads by explicitly introducing charges with a long-range interaction with those obtained by tuning the implicit electrostatic interaction without the long-range interaction. The effects of the chain length of the model and the harmonic bond parameters on the internal density of DPD beads and stress profiles within the vesicles are examined closely. These results are a significant contribution to understanding the stability of the phases and tailoring of the desired vesicles.Pest control effectiveness and residues of pesticides are contradictory concerns in agriculture and environmental conservation. selleck chemical On the premise of not affecting the insecticidal effect, the pesticide residues in the later stage should be degraded as fast as possible. In the present study, composite nanoparticles in a double-layer structure, consisting of imidacloprid (IMI) in the outer layer and plant hormone 24-epibrassinolide (24-EBL) in the inner layer, were prepared by the W/O/W solvent evaporation method using Eudragit RL/RS and polyhydroxyalkanoate as wall materials. The release of IMI in the outer layer was faster and reached the maximum within 24 h, while the release of 24-EBL in the inner layer was slower and reached the maximum within 96 h. The contact angle of the composite nanoparticles was half that of the 5% IMI emulsifiable concentrate (EC), and the deposition of composite nanoparticles on rice was twice that of 5% IMI EC, which increased the pesticide utilization efficiency. Compared with the common pesticide, 5% IMI EC, the insecticidal effect of the composite nanoparticles was stronger than that of planthoppers, with a much lower final residue amount on rice after 21 days. The composite nanoparticles prepared in this study to achieve sustained release of pesticides and, meanwhile, accelerate the degradation of pesticide residues have a strong application potential in agriculture for controlling pests and promoting crop growth.Gas pre-extraction technology in a coal reservoir can not only reduce greenhouse gas (GHG) emissions but also effectively recover coalbed methane (CBM). In this work, we use a geomechanical-coupled gas flow (GCF) model to simulate and analyze the pre-extraction effect of a mining-disturbed coal seam. First, the simulation results of the GCF model are compared with field test data to verify the correctness and reliability of our model. Then, the evolution law of the stress field, permeability field, and gas flow field in the extraction process is analyzed through a case study. The results show that the first principal stress of coal in a mining area increases first and then decreases slowly and reaches the peak value at 5 m. The third principal stress increases gradually at first and becomes stable after 10 m. As the distance from the mining face increases, the permeability and gas pressure of the coal seam show continuous and asymmetric "U"-shaped and "n"-shaped distribution characteristics, respectively. In addition, the recovery effect and abnormal emission factors of CBM are discussed. This study can provide theoretical guidance for optimizing the CBM recovery effect and reducing GHG emissions during mining.Uptake and release kinetics are investigated of a dilute aqueous polymeric-surfactant wetting agent, (ethylene oxide)45-(butylene oxide)10 copolymer, also referred to as poly(oxyethylene)-co-poly(oxybutylene), impregnated into a newly designed silicone-hydrogel lens material. Transient scanning concentration profiles of the fluorescently tagged polymeric surfactant follow Fick's second law with a diffusion coefficient near 10-11 cm2/s, a value 3-4 orders smaller than that of the free surfactant in bulk water. The Nernst partition coefficient of the tagged polymeric wetting agent, determined by fluorescence microscopy and by methanol extraction, is near 350, a very large value. Back-extraction of the polymeric-surfactant wetting agent releases only ∼20% of the loaded amount after soaking the fully loaded lens for over 7 days. The remaining ∼80% is irreversibly bound in the lens matrix. Reverse-phase liquid chromatography of the lens-loaded and lens-extracted surfactant demonstrates that the released wetting agent is more hydrophilic with a higher polarity. Aqueous poly(oxyethylene)-co-poly(oxybutylene) is hypothesized to attach strongly to the lens matrix, most likely to the lens silicone domains. Strong binding leads to slow transient diffusion, to large uptake, and to significant irreversible retention. These characteristics indicate the suitability of using a poly(oxyethylene)-co-poly(oxybutylene) nonionic polymeric surfactant to maintain enhanced lens wettability over time. Methodology and findings from this study provide useful insights for designing sustained-release contact-lens wetting agents and materials.Gloriosine, a colchicine-like natural product, is widely obtained from Gloriosa superba roots. Despite having remarkable anticancer potential, colchicine could not pave its way to the clinic, while gloriosine is yet to be investigated for its pharmacological effects. In the present work, 14 compounds, including gloriosine, were isolated from the G. superba roots and were characterized by NMR spectroscopy. Gloriosine (11) was evaluated for its antiproliferative activity against a panel of 15 human cancer cell lines of different tissues and normal breast cells. Gloroisine (11) displayed significant antiproliferative activity against various cancer cell lines selectively, with IC50 values ranging from 32.61 to 100.28 nM. Further, gloriosine (11) was investigated for its apoptosis-inducing ability and found to form apoptotic bodies. It also inhibited A549 cell migration in the wound healing assay. Finally, molecular docking studies were performed to explore the possible binding modes of gloriosine with the colchicine-binding site of tubulin protein. Our findings suggested that gloriosine might be a potential lead for anticancer drug discovery.The effective utilization of solar energy in synthetic organic chemistry has gained extensive attention owing to its enormous energy and environmentally benign nature. In this context, we designed and synthesized a magnetically retrievable, sole palladium (Pd)-supported polydopamine-coated core@shell (NiFe2O4@TiO2) heterogeneous nanophotocatalyst for Suzuki and Sonogashira coupling reactions under sunlight irradiation. The synthesized catalyst was characterized by powder X-ray diffraction (PXRD), Fourier-transform infrared, UV-vis, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and vibrating sample magnetometer analysis. The photocatalytic activity of the synthesized nanocatalyst under sunlight irradiation was assessed for both Suzuki and Sonogashira coupling reactions, where it worked excellently well with a high yield of the product up to 98 and 96%, respectively. Its efficacy was also investigated in the conversion of substituted substrates in both the coupling reactions into desired biaryls and diarylacetylenes. Unique features of the synthesized catalyst are (i) its effective performance for both the aforesaid coupling reactions under ambient reaction conditions for a short reaction time in polar protic solvents (ethanolic water/EtOH) with good yield without any byproduct, (ii) magnetic retrieval of the catalyst from the reaction mixture employing an external magnet is an added advantage, and (iii) the retrieved catalyst could potentially be reutilized for up to five consecutive runs without appreciable diminution of catalytic efficacy, and its stability was confirmed by inductively coupled plasma optical emission spectroscopy analysis and XRD.The Rosellinia sanctae-cruciana extract was subjected to detailed liquid chromatography tandem mass spectrometry studies. A total of 38 peaks were annotated to m/z 508.26, m/z 510.28, m/z 524.26, m/z 526.28, m/z 540.26, m/z 542.27, and m/z 584.28 [M + H]+. The accurate mass, mutually supported UV/vis spectra, and database search identified these compounds as cytochalasins. Systematic dereplication helped identify a peak at m/z 540.26 [M + H]+ as the new compound. Further, the identified compound was purified by high-performance liquid chromatography and characterized by 2D NMR to be 19,20-epoxycytochalasin N1, a new optical isomer of 19,20-epoxycytochalasin-N. It exhibited substantial cytotoxicity with IC50 values ranging from 1.34 to 19.02 μM. This study shows a fast approach for dereplicating and identifying novel cytochalasin metabolites in crude extracts.Western blotting is a widely used technique for molecular-weight-resolved analysis of proteins and their posttranslational modifications, but high-throughput implementations of the standard slab gel arrangement are scarce. The previously developed Microwestern requires a piezoelectric pipetting instrument, which is not available for many labs. Here, we report the Mesowestern blot, which uses a 3D-printable gel casting mold to enable high-throughput Western blotting without piezoelectric pipetting and is compatible with the standard sample preparation and small (∼1 μL) sample sizes. The main tradeoffs are reduced molecular weight resolution and higher sample-to-sample CV, making it suitable for qualitative screening applications. The casted polyacrylamide gel contains 336, ∼0.5 μL micropipette-loadable sample wells arranged within a standard microplate footprint. Polyacrylamide % can be altered to change molecular weight resolution profiles. Proof-of-concept experiments using both infrared-fluorescent molecular weight protein ladder and cell lysate (RIPA buffer) demonstrate that the protein loaded in Mesowestern gels is amenable to the standard Western blotting steps. The main difference between Mesowestern and traditional Western is that semidry horizontal instead of immersed vertical gel electrophoresis is used. The linear range of detection is at least 32-fold, and at least ∼500 attomols of β-actin can be detected (∼29 ng of total protein from mammalian cell lysates ∼100-300 cells). Because the gel mold is 3D-printable, users with access to additive manufacturing cores have significant design freedom for custom layouts. We expect that the technique could be easily adopted by any typical cell and molecular biology laboratory already performing Western blots.