Field-Programmable-Gate-Array Implemented on Time-to-Digital Converter: Improving its Resolution

The purpose of this investigation is to discover critical experimental factors that could lead to the variation of time measurement by a time-to-digital converter (TDC) implemented on field-programmablegate- array (FPGA). Two pulses were generated by a pulse generator, and the second pulse was given a 20 nanoseconds delay. In an ideal experiment, the mean of the entry data would have been 20 nanoseconds since the two channels (8,c) obtained pulses that were given the same delay. However, due to device errors and quantization errors, which is produced during analog-to-digital conversion, time difference between hits varied from 22.1 to 22.7 nanoseconds. The top test results have shown that the time measurement better than 80 picoseconds was obtained for more than ten tests. FPGA can be used as a base gadget to improve TDC resolution, and although still at the state of development, this particular application will continue to develop and ultimately improve resolutions of Positron Emission Tomography scanners (PET scanner) and future medical imaging

Rhenium Tricarbonyl Complex Featuring Amine Moieties as Molecular Catalysts for Electrocatalytic CO2 Reduction

Molecular catalysts for the electrochemical reduction of CO2 are being investigated for the potential utilization of CO2 as a viable C1 feedstock for the chemical industry and energy economy. Various CO2 reduction products can be generated such as CO, CH3OH, and CH4. Among the several multi-electron reduction products, this study focuses on the proton-coupled, two-electron reduction of CO2 to generate selectively CO (and H2O as the byproduct). Several examples of selective CO2 reduction electrocatalysts, such as Ni(cyclam)^2+, cobalt macrocyclic compounds based on azacalix[4](2,6)pyridines, and FeTDHPP (TDHPP = tetrakis(2',6'-dihydroxylphenyl)porphyrin), feature protic N-H or O-H groups in the vicinity of the reactive metal ion. Hydrogen-bonding like interactions between N-H groups and reduced CO2 intermediates are proposed to stabilize transition states in Ni(cyclam)^2+ and cobalt macrocyclic compound, and the O-H groups in FeTDHPP are found to increase catalytic activity by acting as local proton sources. Inspired by these reports, this study examines the effects of the interactions from the secondary coordination sphere of well-studied Lehn-type catalyst systems for CO2 reduction. Lehn-type pre-catalysts feature Re(CO)3X (X = Cl, Br, and py) moieties coordinated to bipyridine or phenanthroline chelators and have been previously shown to be highly selective for CO2 reduction

Effect of renal impairment on the pharmacokinetics of exenatide

What is already known about this subjec

Designing a Low-Cost Mobile Tracking System for Communication with a Medium Earth Orbit Satellite

An essential part of satellite communication is the orientation of the antenna, which can be difficult to ascertain on mobile platforms such as ships. While equipment to measure orientation accurately at sea exists, current solutions are expensive. This paper describes work toward an antenna orientation system using low-cost Global Position System (GPS) receivers. We investigated two methods: one using the spatial difference between multiple GPS units at the vertices of a polygon, and the other using the differences over time measured using a single GPS unit We tested the antenna orientation system with the Omnispace F2 satellite at the US Electrodynamics, Inc. (USEI) teleport in Brewster, WA. Although non-correlated systematic errors in the GPS receivers made the multiple-GPS system impractical, the time-differential method was able to maintain a satellite lock for the majority of a simple test course. The reliability of this solution may be further improved using a gain-based correction algorithm

One-dimensional manganese-cobalt oxide nanofibres as bi-functional cathode catalysts for rechargeable metal-air batteries

Rechargeable metal-air batteries are considered a promising energy storage solution owing to their high theoretical energy density. The major obstacles to realising this technology include the slow kinetics of oxygen reduction and evolution on the cathode (air electrode) upon battery discharging and charging, respectively. Here, we report non-precious metal oxide catalysts based on spinel-type manganese-cobalt oxide nanofibres fabricated by an electrospinning technique. The spinel oxide nanofibres exhibit high catalytic activity towards both oxygen reduction and evolution in an alkaline electrolyte. When incorporated as cathode catalysts in Zn-air batteries, the fibrous spinel oxides considerably reduce the discharge-charge voltage gaps (improve the round-trip efficiency) in comparison to the catalyst-free cathode. Moreover, the nanofibre catalysts remain stable over the course of repeated discharge-charge cycling; however, carbon corrosion in the catalyst/carbon composite cathode degrades the cycling performance of the batteries

Immune microenvironment in ductal carcinoma in situ: a comparison with invasive carcinoma of the breast

Abstract Background The immune microenvironment in ductal carcinoma in situ (DCIS) and its significance are not well established. This study was conducted to evaluate the immune microenvironment of DCIS including the composition of tumor-infiltrating lymphocyte (TIL) subsets and PD-L1+ immune cells and to compare it with that of invasive breast cancer. Materials and methods A total of 671 cases including three different disease groups of pure DCIS, DCIS with microinvasion (DCIS-M), and invasive carcinoma were included in this study. CD4+, CD8+, and FOXP3+ TIL subsets and PD-L1+ immune cells were detected with immunohistochemistry using tissue microarrays and were analyzed in relation to clinicopathologic characteristics and different disease groups. Results In pure DCIS, high infiltrations of CD4+, CD8+, and FOXP3+ T cells and the presence of PD-L1+ immune cells were associated with high nuclear grade, comedo-type necrosis, hormone receptor (HR) negativity, and high Ki-67 proliferation index. All immune cell infiltrations were higher in invasive carcinoma than in pure DCIS regardless of the HR status. While CD4+ T cells were more abundant than CD8+ T cells in pure DCIS, CD8+ T cells were dominant in invasive carcinoma, especially in HR-negative tumors. Within individual cases of invasive carcinoma with DCIS component, all immune cell subset infiltration was higher in the invasive component than in the DCIS component; however, CD4+ TIL infiltration did not differ between the two components in HR-negative tumors. Comparing pure DCIS, DCIS-M, and DCIS associated with invasive carcinoma (DCIS-INV), CD4+ TIL infiltration revealed a gradual increase from pure DCIS to DCIS-M and DCIS-INV in the HR-negative group, whereas FOXP3+ TIL infiltration was significantly increased in DCIS-INV than in pure DCIS in the HR-positive group. The high infiltration of FOXP3+ TIL and the presence of PD-L1+ immune cells were associated with tumor recurrence in patients with pure DCIS. Conclusions Our study showed that the immune microenvironment differs significantly not only between DCIS and invasive carcinoma but also between pure DCIS, DCIS-M, and DCIS-INV depending on the HR status