Velazquez Malone (seatbrush84)

Achieving phase selectivity during nanoparticle synthesis is important because crystal structure and composition influence reactivity, growth, and properties. Cation exchange provides a pathway for targeting desired phases by modifying composition while maintaining crystal structure. However, our understanding of how to selectively target different phases in the same system is limited. Here, we demonstrate morphology-dependent phase selectivity for wurtzite (wz) CoS, which is hcp, vs pentlandite Co9S8, which is ccp, during Co2+ exchange of roxbyite Cu1.8S plates, spheres, and rods. The plates form wz-CoS, the spheres form both wz-CoS and Co9S8, and the rods form Co9S8. The plates, spheres, and rods have nearly identical widths but increase in length in the direction that the close-packed planes stack, which influences the ability of the anions to shift from hcp to ccp during cation exchange. This morphology-dependent behavior, which correlates with the number of stacked close-packed planes, relies on an anion sublattice rearrangement that is concomitant with cation exchange, thereby providing a unique pathway by which crystal structure can be controlled and phase selectivity can be achieved during nanocrystal cation exchange.Elemental imaging gives insight into the fundamental chemical makeup of living organisms. Every cell on Earth is comprised of a complex and dynamic mixture of the chemical elements that define structure and function. Many disease states feature a disturbance in elemental homeostasis, and understanding how, and most importantly where, has driven the development of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) as the principal elemental imaging technique for biologists. This review provides an outline of ICP-MS technology, laser ablation cell designs, imaging workflows, and methods of quantification. Detailed examples of imaging applications including analyses of cancers, elemental uptake and accumulation, plant bioimaging, nanomaterials in the environment, and exposure science and neuroscience are presented and discussed. Recent incorporation of immunohistochemical workflows for imaging biomolecules, complementary and multimodal imaging techniques, and image processing methods is also reviewed.Glutathione S-transferase genes in the epsilon group were reported to function in insecticide resistance. SlGSTE12 was validated to be overexpressed in pyrethroid- and organophosphate-resistant populations of Spodoptera litura compared to a susceptible population. A functional study of heterologously expressed SlGSTE12 showed that Km and Vmax for 1-chloro-2,4-dinitrobenzene (CDNB) conjugating activity were 0.70 ± 0.18 mmol L-1 and 90.6 ± 9.4 nmol mg-1 min-1, respectively. β-Cypermethrin and cyhalothrin showed much weaker inhibition of SlGSTE12 activity to CDNB conjugation than fenvalerate, chlorpyrifos, and phoxim. Ultrahigh-performance liquid chromatography analysis showed that SlGSTE12 had significant metabolism activity to fenvalerate and phoxim both in vitro and in Escherichia coli, especially to chlorpyrifos, and slight metabolism activity toward cyhalothrin only in vitro. Silencing of SlGSTE12 by RNAi increased the mortality to fenvalerate, cyhalothrin, and chlorpyrifos significantly. SlGSTE12 also had a significant antioxidant ability against cumene hydroperoxide. Our study suggested that SlGSTE12 could metabolize phoxim, fenvalerate, cyhalothrin, and especially chlorpyrifos. SlGSTE12 might also participate in pyrethroid and organophosphate resistance by antioxidant activity.During haze periods in the North China Plain, extremely high NO concentrations have been observed, commonly exceeding 1 ppbv, preventing the classical gas-phase H2O2 formation through HO2 recombination. Surprisingly, H2O2 mixing ratios of about 1 ppbv were observed repeatedly in winter 2017. Combined field observations and chamber experiments reveal a photochemical in-particle formation of H2O2, driven by transit