Denckerhoneycutt7970

A one-pot method was developed for the preparation of 2H-azirine-2-carbonylbenzotriazoles, formed by the reaction of benzotriazole with 2H-azirine-2-carbonyl chlorides, which were generated by the Fe(ii)-catalyzed isomerization of 5-chloroisoxazoles. The Co(ii)-catalyzed reaction of 2H-azirine-2-carbonylbenzotriazoles with 1,3-diketones provides 2-((benzotriazol-1-yl)carbonyl)pyrroles in moderate to good yields. Base-promoted annulations of 2-((benzotriazol-1-yl)carbonyl)pyrroles with aldehydes, ketones, isocyanates and isothiocyanates afford various substituted pyrrolo[1,2-c]oxazole and 1H-pyrrolo[1,2-c]imidazole derivatives in moderate to high yields. The 6-acyl group of these adducts can be removed by triflic acid, giving further new pyrrolo-fused O- and N-heterocycles, such as 6-unsubstituted pyrrolo[1,2-c]oxazol-1(3H)-one and 1H-pyrrolo[1,2-c]imidazole-1,3(2H)-dione, while the 6-acetyl substituent of 1H-pyrrolo[1,2-c]imidazole-1,3(2H)-dione, when treated with POCl3/pyridine, is transformed into the 6-ethynyl substituent.Numerous physical models have been proposed to explain how cell motility emerges from internal activity, mostly focused on how crawling motion arises from internal processes. Here we offer a classification of self-propulsion mechanisms based on general physical principles, showing that crawling is not the only way for cells to move on a substrate. We consider a thin drop of active matter on a planar substrate and fully characterize its autonomous motion for all three possible sources of driving (i) the stresses induced in the bulk by active components, which allow in particular tractionless motion, (ii) the self-propulsion of active components at the substrate, which gives rise to crawling motion, and (iii) a net capillary force, possibly self-generated, and coupled to internal activity. We determine travelling-wave solutions to the lubrication equations as a function of a dimensionless activity parameter for each mode of motion. Numerical simulations are used to characterize the drop motion over a wide range of activity magnitudes, and explicit analytical solutions in excellent agreement with the simulations are derived in the weak-activity regime.The controlled aggregation of colloidal particles is not only a widespread natural phenomenon but also serves as a tool to design complex building blocks with tailored shape and functionalities. However, the quantitative characterization of such heteroaggregation processes remains challenging. Here, we demonstrate the use of analytical centrifugation to characterize the heteroaggregation of silica particles and soft microgels bearing similar surface charges. We investigate the attachment as well as the stability of the formed heteroaggregates as a function of particle to microgel surface ratio, microgel size and the influence of temperature. The attachment of microgels onto the colloidal particles induces a change in the sedimentation coefficient, which is used to quantitatively identify the number of attached microgels. We corroborate the shift in sedimentation coefficient by computer simulations of the frictional properties of heteroaggregates via a modified Brownian dynamic algorithm. The comparison between theoretical investigations and experiments suggest that the microgels deform and flatten upon attachment.The effect of humidity on the ionic transport in the amorphous phase of poly(ethylene oxide) thin films has been studied by local dielectric spectroscopy. We explored a controlled humidity range between 15% RH and 50% RH. AFM-based local dielectric imaging allowed the thin film topography and the corresponding dielectric contrast maps to be obtained simultaneously. No humidity effect on the film topography was observed whereas large variation of the dielectric signal could be detected. In addition, we observed a clear dielectric contrast in different locations on the thin film surface. At selected regions with high contrast in the dielectric maps, we performed nanoDielectric Spectroscopy (nDS) measurements covering the frequency range from 5 Hz to 100 kHz. By modeling these spectroscopy results, we quantified the conductivity of the amorphous phase of the semicrystalline poly(ethylene oxide) films. The crystalline fraction of the PEO thin films was extracted and found to be about 36%, independently of humidity. However, the average conductivity increased by a factor of 25 from 2 × 10-10 to 5 × 10-9 S cm-1, by changing environmental humidity in the explored % RH range.van der Waals (vdWs) heterostructures, combining different two-dimensional (2D) layered materials with diverse properties, have been demonstrated to be a very promising platform to explore a new physical phenomenon and realize various potential applications in atomically thin electronic and optoelectronic devices. Here, we report the controlled growth of vertically stacked β-In2Se3/MoS2 vdWs heterostructures (despite the existence of large lattice mismatching ∼29%) through a typical two-step chemical vapor deposition (CVD) method. The crystal structure of the achieved heterostructures is characterized by transmission electron microscopy, where evident Moiré patterns are observed, indicating well-aligned lattice orientation. Strong photoluminescence quenching is obeserved in the heterostructure, revealing effective interlayer charge transfer at the interface. Electrical devices are further constructed based on the achieved heterostructures, which have a high on/off ratio and a typical rectifying behavior. Upon laser irradiation, the devices show excellent photosensing properties. A high responsivity of 4.47 A W-1 and a detectivity of 1.07 × 109 Jones are obtained under 450 nm laser illumination with a bias voltage of 1 V, which are much better than those of heterostructures grown via CVD. Most significantly, the detection range can be extended to near-infrared due to the relatively small bandgap nature of β-In2Se3. With 830 nm laser illumination, the devices also show distinct photoresponses with fast response speed even when operating at room temperature. The high-quality β-In2Se3/MoS2 heterostructures broaden the family of the 2D layered heterostructure system and should have significant potential applications in high-performance broadband photodetectors.Magnesium hydride (MgH2) has been considered as a promising hydrogen storage material for buildings that are powered by hydrogen energy, but its practical application is hampered by poor kinetics and unstable thermodynamics. Herein, we describe a feasible method for preparing FeNi nanoparticles dispersed on reduced graphene oxide nanosheets (FeNi/rGO), and we confirmed that excellent catalytic effects increased the hydrogen storage performance of MgH2. 5 wt% FeNi/rGO-modified MgH2 began to release hydrogen at 230 °C and liberated 6.5 wt% H2 within 10 min at 300 °C. As for the hydrogenation process, the dehydrogenated sample absorbed 5.4 wt% H2 within 20 min at 125 °C under a hydrogen pressure of 32 bar. More importantly, a hydrogen capacity of 6.9 wt% was maintained after 50 cycles without compromising the kinetics during each cycle. A unique catalytic mechanism promoted synergetic effects between the in situ-formed Mg2Ni/Mg2NiH4, Fe, and rGO that efficiently promoted hydrogen dissociation and diffusion along the Mg/MgH2 interface, anchored the catalyst, and prevented MgH2 from aggregation and growth.We present the plasmon-enhanced nonlinear nanofocusing of a gold (Au) nanoprism array substrate (ANAS) driven via an ultrafast azimuthal vector beam (AVB). Theoretical calculations show that the electric-field intensity of the ANAS vertically excited via the femtosecond AVB is higher than that of LPB excitation. In this experiment, the second-order surface nonlinear optical response of the ANAS is adopted to examine the nonlinear plasmonic nanofocusing of the ANAS, and it was observed that the second harmonic (SH) intensity of the ANAS excited via the femtosecond AVB is ∼3.8 times higher than that of LPB excitation, revealing that the ANAS under AVB excitation has a better nonlinear plasmonic nanofocusing characteristic than that under LPB excitation. Furthermore, the GaSe nanosheets are transferred on the ANAS to examine the nonlinear plasmonic nanofocusing of the ANAS. The SH intensity of the GaSe nanosheets deposited on the ANAS via the femtosecond AVB excitation has been enhanced ∼4.7 times than that of LPB excitation, indicating that the ANAS via AVB excitation has better nonlinear plasmonic nanofocusing than that of LPB excitation. This method may be used as a nonlinear nanofocusing light source to increase the light-matter nonlinear interaction.BACKGROUND DHA can regulate various physiological functions of cells. Our group has clarified the immunomodulatory activity and molecular mechanism of DHA on RAW264.7 cells. However, the effect of DHA on the membrane fatty acid environment and the activation of signaling pathways on the cell membrane is still not clear. METHODS In this study, we evaluated the fluidity, the potential and the fatty acid, phospholipid and protein composition of the RAW264.7 cell membrane by DHA treatment. RESULTS The fluidity of the RAW264.7 cell membrane was increased by DHA treatment. The results of membrane potential analysis suggested that DHA (2.4 μM) significantly reduced the surface potential of the cell membrane, which might influence the fluidity of cell membranes. selleckchem In addition, the fatty acids and phospholipids were measured and the results indicated that DHA treatment (2.4 μM) altered the lipid environment and the composition of phospholipids on the RAW264.7 cell membrane. Then the LC-MS/MS-based label free quantitative proteomics approach was applied to identify a total of 86 differential proteins in the 2.4 μM DHA and control groups (>2.0-fold change or less then 0.5-fold change in protein expression); these proteins are most frequently related to the cell response to stimuli and the response to stress. These results suggested that DHA could alter the fluidity, the potential, the fatty acid and phospholipid composition of the RAW264.7 cell membrane, eventually affecting the proteins of the cell membrane, especially the changes in Siglec 1, iNOS, GPR120, Ras and MEK expressions (validated by western blot analysis), which are likely associated with the activation of the intracellular signaling pathway in RAW264.7 cells by DHA treatment.A multifunctional plasmonic gold chip has been constructed for early diagnosis and highly effective killing of bacteria, which is critical for human health. The chip features high bacterial capture efficiency, plasmon-enhanced fluorescence (PEF) and surface-enhanced Raman scattering (SERS) and can act as a highly sensitive sensor for dual-mode bacteria imaging and detection (down to 102 CFU mL-1) with good reliability and accuracy. The developed assay can distinguish Gram-positive S. aureus bacteria from Gram-negative E. coli bacteria, providing valuable information for therapy. Importantly, the chip presents excellent photothermal antibacterial activity (98%) and can inactivate both Gram-positive and Gram-negative bacteria in situ. Furthermore, the chip was used to effectively promote the wound healing process in bacteria infected mice in vivo, showing great potential for antibacterial applications.