Reduced dose uncertainty in MRI-based polymer gel dosimetry using parallel RF transmission with multiple RF sources

In this work, we present the feasibility of using a parallel RF transmit with multiple RF sources imaging method (MultiTransmit imaging) in polymer gel dosimetry. Image quality and B₁ field homogeneity was statistically better in the MultiTransmit imaging method than in conventional single source RF transmission imaging method. In particular, the standard uncertainty of R ₂ was lower on the MultiTransmit images than on the conventional images. Furthermore, the MultiTransmit measurement showed improved dose resolution. Improved image quality and B₁ homogeneity results in reduced dose uncertainty, thereby suggesting the feasibility of MultiTransmit MR imaging in gel dosimetry.     

Efficient synthesis of unsymmetric diarylalkynes from decarboxylative coupling in a continuous flow reaction system

Unsymmetric diaryl alkynes were synthesized from the palladium-catalyzed decarboxylative coupling of aryl halides and propiolic acid using a continuous flow reaction system. This flow chemistry system continuously gave the desired products in moderate to good yields, and produced less byproduct than was formed in the batch reaction.     

Compressible Navier–Stokes system with hard sphere pressure law and general inflow–outflow boundary conditions

We prove the existence of a weak solution to the compressible Navier–Stokes system with hard sphere possibly non-monotone pressure law involving, in particular, the Carnahan–Starling model [2] largely employed in various physical and industrial applications. We take into account large velocities prescribed at the boundary of a bounded piecewise $C^2$ domain and large densities prescribed at the inflow boundary without any restriction neither on the shape of the inflow/outflow boundaries nor on the shape of the domain.     

Compact Differences of Composition Operators on the Bergman Spaces Over the Ball

The compact differences of composition operators acting on the weighted L ²-Bergman space over the unit disk is characterized by the angular derivative cancellation property and due to Moorhouse. In this paper we extend Moorhouse’s characterization, as well as some related results, to the ball and, at the same time, to the weighted L ^p -Bergman space for the full range of p.     

Cu/Zn Incorporation During Purification of Soluble Human EC-SOD from E. coli Stabilizes Proper Disulfide Bond Formation

Extracellular superoxide dismutase (EC-SOD) is the only enzyme that removes superoxide radical in the extracellular space. The reduction of EC-SOD is linked to many diseases, suggesting that the protein may have therapeutic value. EC-SOD is reported to be insoluble and to make inclusion bodies when overexpressed in the cytoplasm of Escherichia coli. The refolding process has the advantage of high yield, but has the disadvantage of frequent aggregation or misfolding during purification. For the first time, this study shows that fusion with maltose-binding protein (MBP), N-utilization substance protein A, and protein disulfide isomerase enabled the soluble overexpression of EC-SOD in the cytoplasm of E. coli. MBP-tagged human EC-SOD (hEC-SOD) was purified by MBP affinity and anion exchange chromatography, and its identity was confirmed by MALDI-TOF MS analysis. The purified protein showed good enzyme activity in vitro; however, there was a difference in metal binding. When copper and zinc were incorporated into hEC-SOD before MBP tag cleavage, the enzymatic activity was higher than when the metal ions were bound to the purified protein after MBP tag cleavage. Therefore, the enzymatic activity of hEC-SOD is associated with metal incorporation and protein folding via disulfide bond.     

Aptamer‐Assisted Gold Nanoparticles/PEDOT Platform for Ultrasensitive Detection of LPS

Neatly arranged gold nanoparticles (AuNPs) were directly electrodeposited on an electrochemically polymerized self‐assembled monolayer (SAM) of thiol‐functionalized 3,4‐ethylenedioxythiophene (EDOT) derivative, EDTMSHA. A thiolated single‐stranded DNA (ssDNA) aptamer with high specificity to LPS was immobilized on the AuNPs/conducting polymer composite film, serving as sensing platform for LPS detection. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), scanning electron microscope (SEM), and atomic force microscopy (AFM) were utilized to characterize the modification and detection processes. The electron transfer resistance was found to have a linear relationship with LPS concentration from 0.1 pg/mL to 1 ng/mL.     

Stepwise synthesis of metal-organic frameworks: replacement of structural organic linkers

We demonstrate how a single-crystal to single-crystal transformation resulting from bridging-linker replacement is possible in extended 2D and 3D metal-organic frameworks (MOFs) by introducing pillared paddlewheel MOF structures into a solution containing dipyridyl linkers. No lateral movement of the layers was observed during this transformation, creating a templating effect from the "parent" structure to the "daughter" structure. A previously unattainable structure was obtained by a two-step synthetic method utilizing the bridging-linker replacement transformation method. Additionally, a bridging-linker insertion was observed when excess linker was used with the 2D MOF structure, inducing an overall 2D to 3D transformation.