Cu-Catalyzed Aerobic Oxidative Esterification of Acetophenones with Alcohols to α‑Ketoesters

Copper-catalyzed aerobic oxidative esterification of acetophenones with alcohols using molecular oxygen has been developed to form a broad range of α-ketoesters in good yields. In addition to reporting scope and limitations of our new method, mechanism studies are reported that reveal that the carbonyl oxygen in the ester mainly originated from dioxygen

CO₂ Dynamics in a Metal–Organic Framework with Open Metal Sites

Metal–organic frameworks (MOFs) with open metal sites are promising candidates for CO₂ capture from dry flue gas. We applied <i>in situ</i> ¹³C NMR spectroscopy to investigate CO₂ adsorbed in Mg₂(dobdc) (H₄dobdc = 2,5-dihydroxyterephthalic acid; Mg-MOF-74, CPO-27-Mg), a key MOF in which exposed Mg²⁺ cation sites give rise to exceptional CO₂ capture properties. Analysis of the resulting spectra reveals details of the binding and CO₂ rotational motion within the material. The dynamics of the motional processes are evaluated via analysis of the NMR line shapes and relaxation times observed between 12 and 400 K. These results form stringent and quantifiable metrics for computer simulations that seek to screen and improve the design of new MOFs for CO₂ capture

Functional effects of miR-486 in c-Kit-sorted progenitor basal cell culture preparations.

<p>(A, B) Basal cells purified from OE of regenerating mice were seeded for short primary culture assay. Characterization of cultures at 24 hours confirms the presence of OE progenitors. Antibody against the neuron-specific transcription factor OAZ (magenta) labels the nuclei of neuron-committed GBCs and nascent or immature neurons; antibody against SOX2 (green) labels nuclei of cells scattered in basal cell islands, consistent with the growth of “upstream” undifferentiated GBCs. Culture composition is quantified in (B), n = 3. (C, D) Cultures were transfected after 24 hours with either miR486 or a scrambled control RNA. 48 hours post transfection, cells were fixed and stained for TUJ1 and DAPI and subsequently quantified. Although there was no significant change in proliferation by EdU incorporation (E), miR-486 treatment reduced the total amount of TUJ1 positive neurons by 30.05% ± 5.88 (p = 0.0014) normalized to scrambled control group (F); n = 8, mean ± S.E.M; student’s t-test. Bar = 20μm in A, 120μm in C and D.</p

Antibody reagents.

<p>Antibody reagents.</p

Confirmation by <i>in situ</i> hybridization for miR-486 enrichment in the c-Kit (-) population.

<p>MiR-486, identified as highly enriched in the c-Kit (-) cell fraction from regenerating olfactory epithelium, was chosen for further study to confirm the microarray findings. <i>In situ</i> hybridization was performed on normal adult mouse olfactory epithelium tissue sections; a miR-486 probe (A, B) reveals expression by cells throughout the neuronal layers (Neu), with little signal in the underlying lamina propria. At high magnification (B) an absence of signal in the c-Kit (+) basal cell layers (BCs) or in the apical sustentacular cell layers (Sus) is evident. (C) Hybridization using a scrambled control probe shows no signal. (D-K) Staining with cell type-specific markers was performed to define the OE cell populations. Antibody against c-Kit (D, E) labels only basal cells slightly above the basal lamina; antibody against OMP (F) labels mature neurons in the mid to upper portions of the OE; antibody against Tuj1 (G, H) labels the somata of immature neurons just above the basal cell layers, as well as dendrites extending apically; antibody against SOX2 (I) labels nuclei of a subset of basal cells near the basal lamina and also the sustentacular cell nuclei at the top of the epithelium; antibody against OAZ (J) localizes to nuclei of late GBCs and nascent neurons in deep layers of the OE; antibody against CK5 (K) labels HBCs along the basal lamina. (L) Cell layers and the markers used here are summarized schematically. Arrowheads or dashed line (in B) mark basal lamina; NEUm = mature neurons; NEUi = immature neurons; scale bar in B = 10 μm, in H = 20 μm.</p

Schematic of experimental strategy to identify differential miRNA expression in olfactory epithelial cells.

<p>(A) The olfactory epithelium, lining portions of the mouse nasal cavity, contains basal stem and progenitor cells, immature differentiating olfactory receptor neurons, mature neurons, sustentacular cells, and microvillar cells. (B) Following experimental lesion with methimazole, spared basal globose cells remain, and their expansion and differentiation (C) lead to rapid epithelial reconstitution. (D) Olfactory epithelial cells harvested 10 days following lesion are enriched with basal progenitors marked by surface expression of c-Kit. The c-Kit (+) basal cells were isolated by immunoselection, and total RNA was purified from the c-Kit (+) fraction or the c-Kit (-) fraction was analyzed by miRNA microarrays.</p

MiRNAs differentially downregulated in c-Kit (+ve) mouse globose cells post injury.

<p>MiRNAs differentially downregulated in c-Kit (+ve) mouse globose cells post injury.</p

MiRNAs differentially upregulated in c-Kit (+ve) mouse globose cells post injury.

<p>MiRNAs differentially upregulated in c-Kit (+ve) mouse globose cells post injury.</p

Differential miRNA expession in cell populations of the olfactory epithelium.

<p>Heatmap shows microarray results of top 28 miRNAs most downregulated (A) and top 10 miRNAs most upregulated (B) in c-Kit (+) versus c-Kit (-) fractions of mouse olfactory epithelium 10 days post olfactory lesion. N = 3 per group. Criteria used for selection is at least 4 fold change in transcript expression with p<0.05 based on t-test with Benjamini-Hochberg multiple testing correction. (C) QPCR validation shows miR-486 is 17 fold downregulated in c-Kit (+) versus (-) fractions of mouse olfactory epithelium 10 days post nasal injury. N = 3 per group. Data are Mean ± S.E.M. p = 0.001 based on t-test using delta Cts.</p

Thermal Properties and Kinetics of Al/α-MnO2 Nanostructure Thermite

<div><p>In this work, thermal properties and kinetics of Al-nanoparticles/α-MnO2 nanorods thermite were reported. The α-MnO2 nanorods were synthesized using a hydrothermal method and were characterized by X-ray powder diffraction (XRD) and X-ray photoelectron spectra (XPS), then combined with Al nanoparticles based on the ultrasonic mixing method to prepare the nanostructure thermite. Besides, both pure components and mixture were characterized by field emission scanning electron microscopy (FE-SEM) to observe their morphologies and structures. Subsequently, the thermal properties of Al/α-MnO2 nanostructure thermite were studied on the basis of thermogravimetric-differential scanning calorimetry (TG-DSC). According to the TG-DSC tests, the calculation results of activation energy for kinetics of Al/α-MnO2 thermite were obtained using different isoconversional methods. It was found that Al/α-MnO2 nanostructure thermite has high heat release and low onset temperature, and the heat release of the nanostructure thermite was approximately 1146.6 J g -1.</p></div