Preclinical Evaluation of [18F]FACH in Healthy Mice and Piglets: An 18F-Labeled Ligand for Imaging of Monocarboxylate Transporters with PET

The expression of monocarboxylate transporters (MCTs) is linked to pathophysiological changes in diseases, including cancer, such that MCTs could potentially serve as diagnostic markers or therapeutic targets. We recently developed [¹⁸F]FACH as a radiotracer for non-invasive molecular imaging of MCTs by positron emission tomography (PET). The aim of this study was to evaluate further the specificity, metabolic stability, and pharmacokinetics of [¹⁸F]FACH in healthy mice and piglets. We measured the [¹⁸F]FACH plasma protein binding fractions in mice and piglets and the specific binding in cryosections of murine kidney and lung. The biodistribution of [¹⁸F]FACH was evaluated by tissue sampling ex vivo and by dynamic PET/MRI in vivo, with and without pre-treatment by the MCT inhibitor α-CCA-Na or the reference compound, FACH-Na. Additionally, we performed compartmental modelling of the PET signal in kidney cortex and liver. Saturation binding studies in kidney cortex cryosections indicated a K_D of 118 ± 12 nM and B_max of 6.0 pmol/mg wet weight. The specificity of [¹⁸F]FACH uptake in the kidney cortex was confirmed in vivo by reductions in AUC_0–60min after pre-treatment with α-CCA-Na in mice (−47%) and in piglets (−66%). [¹⁸F]FACH was metabolically stable in mouse, but polar radio-metabolites were present in plasma and tissues of piglets. The [¹⁸F]FACH binding potential (BP_ND) in the kidney cortex was approximately 1.3 in mice. The MCT1 specificity of [¹⁸F]FACH uptake was confirmed by displacement studies in 4T1 cells. [¹⁸F]FACH has suitable properties for the detection of the MCTs in kidney, and thus has potential as a molecular imaging tool for MCT-related pathologies, which should next be assessed in relevant disease models.     

Facile and rapid synthesis of piperidinium-6-amino-4-aryl-3, 5-dicyano-1,4-dihydropyridine-2-thiolate

A fast and convenient protocol for the synthesis of a new class of piperidin-1-ium 6-amino-4-aryl-3,5-dicyano-1,4-dihydropyridine-2-thiolate (piperidinium salt) derivatives is developed by the one-pot, three-component reactions of cyanothioacetamide, aromatic aldehydes and piperidine in dichloromethane at room temperature. The features such as operational simplicity, mild conditions, absence of catalyst, high yields in short reaction times, simple purification process with no chromatographic technique make the protocol highly attractive.     

Influence of monovalent alkaline metal cations on binder-free nano-zeolite X in para-xylene separation

The adsorption process was studied for separating para-xylene from xylene mixture on modified nano-zeolite X in a breakthrough system. Nano-zeolitic adsorbent with different ratios of SiO2/Al2O3 was synthesized through hydrothermal process and ion-exchanged with alkaline metal cations like lithium, sodium and potassium. The product was characterized by X-ray diffraction, scanning electron microscopy (SEM), nitrogen adsorption, transform electron microscopy (TEM) and in situ Fourier transform infrared (FTIR) spectroscopy. The influence of nano-zeolite water content and desorbent type on the selectivity of para-xylene toward other C8 aromatic isomers was studied. The optimization of adsorption process was also investigated under variable operation conditions. The isotherm for each isomer of C8 aromatics and the desorbents possess the adsorption characteristics of Langmuir type. The selectivity factor of para-xylene relative to each of meta-xylene, ortho-xylene and ethylben-zene under the optimum conditions obtained to be 5.36, 2.43 and 3.22, in the order given.     

Techno‐Economic Comparison of a 7‐MWth Biomass Chemical Looping Gasification Unit with Conventional Systems

The chemical looping process is an alternative method to provide conventional gasification (CG) systems with the required oxygen. The syngas produced via chemical looping has a higher calorific value than that generated by a conventional process with air. For comparison, a conventional gasification unit with pure oxygen (CGPO) and a chemical looping gasification (CLG) system were simulated with Aspen Plus. The CGPO reactor consisted of a bubbling fluidized bed and sand as bed material with oxygen supplied via a pressure swing adsorption unit. The CLG comprised a bubbling fluidized‐bed gasifier working in parallel with a fast fluidized‐bed oxidizer. The total capital investment (TCI) of the CLG unit was higher than that of the CGPO unit but the annual operating cost of the former was less which repays the difference in TCI in less than six years.     

Predictive Dynamic Model of Air Separation by Pressure Swing Adsorption

A general dynamic model is developed for separation of air over a carbon molecular sieve and a zeolite adsorbent for production of nitrogen and oxygen. The proposed model is validated using experimental data from working laboratory scale N₂–PSA and laboratory scale O₂–PSA systems. Simulations studies are performed to investigate the effect of changing various process variables, such as the duration of PSA steps, bed length and feed inlet velocity.     

Effects of Defects on the Temperature‐Dependent Thermal Conductivity of Suspended Monolayer Molybdenum Disulfide Grown by Chemical Vapor Deposition

It is understood that defects of the atomic arrangement of the lattice in 2D molybdenum disulfide (MoS₂) grown by chemical vapor deposition (CVD) can have a profound effect on the electronic and optical properties. Beyond these it is a major prerequisite to also understand the fundamental effect of such defects on phonon transport, to guarantee the successful integration of MoS₂ into the solid‐state devices. A comprehensive joint experiment‐theory investigation to explore the effect of lattice defects on the thermal transport of the suspended MoS₂ monolayer grown by CVD is presented. The measured room temperature thermal conductivity values are 30 ± 3.3 and 35.5 ± 3 W m^?1 K^?1 for two samples, which are more than two times smaller than that of their exfoliated counterpart. High‐resolution transmission electron microscopy shows that these CVD‐grown samples are polycrystalline in nature with low angle grain boundaries, which is primarily responsible for their reduced thermal conductivity. Higher degree of polycrystallinity and aging effects also result in smoother temperature dependency of thermal conductivity (κ) at temperatures below 100 K. First‐principles lattice dynamics simulations are carried out to understand the role of defects such as isotopes, vacancies, and grain boundaries on the phonon scattering rates of our CVD‐grown samples.     

Investigating the optical NOR gate using plasmonic nanorods

In this paper, a coherent perfect absorption‐type NOR gate based on plasmonic nano particles is proposed. It consists of two plasmonic nanorod arrays on top of two serial arms with quartz substrate. The operation principle is based on the absorbable formation of a conductive path in the dielectric layer of a plasmonic nanoparticle waveguide. Because the coherent perfect absorption efficiency depends strongly on the number of plasmonic nanorods and the locations of nanorods, an efficient binary optimization method based the Particle Swarm Optimization algorithm is used to design an optimized array of the plasmonic nanorods in order to achieve the maximum absorption coefficient in the ‘off’ state and the minimum absorption coefficient in the ‘on’ state. In Binary Particle Swarm Optimization, a group of birds consists a matrix with binary entries, control the presence (‘1’) or the absence (‘0’) of nanorods in the array. Copyright © 2016 John Wiley & Sons, Ltd.     

Prediction of Surface Flow by Forcing of Climate Forecast System Reanalysis Data

Meteorological data are key variables for hydrologists to simulate the rainfall-runoff process using hydrological models. The collection of meteorological variables is sophisticated, especially in arid and semi-arid climates where observed time series are often scarce. Climate Forecast System Reanalysis (CFSR) Data have been used to validate and evaluate hydrological modeling throughout the world. This paper presents a comprehensive application of the Soil and Water Assessment Tool (SWAT) hydrologic simulator, incorporating CFSR daily rainfall-runoff data at the Roodan study site in southern Iran. The developed SWAT model including CFSR data (CFSR model) was calibrated using the Sequential Uncertainty Fitting 2 algorithm (SUFI-2). To validate the model, the calibrated SWAT model (CFSR model) was compared with the observed daily rainfall-runoff data. To have a better assessment, terrestrial meteorological gauge stations were incorporated with the SWAT model (Terrestrial model). Visualization of the simulated flows showed that both CFSR and terrestrial models have satisfactory correlations with the observed data. However, the CFSR model generated better estimates regarding the simulation of low flows (near zero). The results of the uncertainty analysis showed that the CFSR model predicted the validation period more efficiently. This might be related with better prediction of low flows and closer distribution to observed flows. The Nash-Sutcliffe (NS) coefficient provided good- and fair-quality modeling for calibration and validation periods for both models. Overall, it can be concluded that CFSR data might be promising for use in the development of hydrological simulations in arid climates, such as southern Iran, where there are shortages of data and a lack of accessibility to the data.