Histone Deacetylase 2 (HDAC2) Inhibitors Containing Boron

Histone deacetylase enzymes (HDACs) are responsible for the global silencing of tumour-suppressor genes. Treatment with a histone deacetylase inhibitor (HDACi) can reverse this process and restore normal cell function. Herein, we report a small series of boron-based (boronic acid, boronate ester and closo-1,2-carborane) HDAC2 inhibitors with IC₅₀ values in the nanomolar range. The boronate ester 4 b was the most potent compound assessed in this study (IC₅₀=40.6±1.5 nM), followed closely by the 1,2-closo-carborane (IC₅₀=42.9±1.5 nM). Compound 4 b exceeds the potency of the related gold-standard HDAC pan-inhibitor vorinostat ( 1 ) toward this particular HDAC isoform.     

Tuning Thermal Transport Through Atomically Thin Ti3C2Tz MXene by Current Annealing in Vacuum

Heat transport across vertical interfaces of heterogeneous 2D materials is usually governed by the weak Van der Waals interactions of the surface‐terminating atoms. Such interactions play a significant role in thermal transport across transition metal carbide and nitride (MXene) atomic layers due to their hydrophilic nature and variations in surface terminations. Here, the metallicity of atomically thin Ti₃C₂T_z MXene, which is also verified by scanning tunneling spectroscopy for the first time, is exploited to develop a self‐heating/self‐sensing platform to carry out direct‐current annealing experiments in high (<10^?8 bar) vacuum, while simultaneously evaluating the interfacial heat transport across a Ti₃C₂T_z/SiO₂ interface. At room temperature, the thermal boundary conductance (TBC) of this interface is found, on average, to increase from 10 to 27 MW m^?2 K^?1 upon current annealing up to the breakdown limit. In situ heating X‐ray diffraction and X‐ray photo‐electron spectroscopy reveal that the TBC values are mainly affected by interlayer and interface spacing due to the removal of absorbents, while the effect of surface termination is negligible. This study provides key insights into understanding energy transport in MXene nanostructures and other 2D material systems.     

Anharmonic analysis of defective crystals with many-body interactions using symmetry reduction

In this paper we first classify and formulate various types of defects with respect to their symmetries and then show that with this general formulation, one can study the structures and energetics of defects in different crystalline materials effectively. We present all the calculations for the embedded-atom-type potentials but the formulation can, in principle, be applied for any many-body interatomic potential. As examples of defects in crystals with many-body interactions, we study point defects, free surfaces and grain boundaries in fcc Cu and grain boundaries in NiAl. We discuss free surface modelling by relaxing both a semi-infinite lattice and a slab with increasing finite thickness. We demonstrate through several numerical examples that our general framework of anharmonic lattice statics can be used for comparing different interatomic potentials in terms of the structure and energy they predict for a given defect. In the case of fcc Cu, we show how both the structures and energetics of different defects can strongly depend on the choice of potentials.     

New Class of Electrocatalysts Based on 2D Transition Metal Dichalcogenides in Ionic Liquid

The optimization of traditional electrocatalysts has reached a point where progress is impeded by fundamental physical factors including inherent scaling relations among thermokinetic characteristics of different elementary reaction steps, non‐Nernstian behavior, and electronic structure of the catalyst. This indicates that the currently utilized classes of electrocatalysts may not be adequate for future needs. This study reports on synthesis and characterization of a new class of materials based on 2D transition metal dichalcogenides including sulfides, selenides, and tellurides of group V and VI transition metals that exhibit excellent catalytic performance for both oxygen reduction and evolution reactions in an aprotic medium with Li salts. The reaction rates are much higher for these materials than previously reported catalysts for these reactions. The reasons for the high activity are found to be the metal edges with adiabatic electron transfer capability and a cocatalyst effect involving an ionic‐liquid electrolyte. These new materials are expected to have high activity for other core electrocatalytic reactions and open the way for advances in energy storage and catalysis.     

A distributed recovery block approach to fault-tolerant executionof application tasks in hypercubes

An approach to fault-tolerant execution of real-time application tasks in hypercubes is proposed. The approach is based on the distributed recovery block (DRB) scheme and does not require special hardware mechanisms in support of fault tolerance. Each task is assigned to a pair of processors forming a DRB computing station for execution in a dual-redundant and self-checking mode. Assignment of all tasks in an application in such a form is called the full DRB mapping. The DRB scheme was developed as an approach to uniform treatment of hardware and software faults with the effect of fast forward recovery. However, if the system developer is concerned with hardware fault possibilities only, then forming DRB stations becomes a mechanical process not burdening the application software designer in any way. A procedure for converting an efficient nonredundant task-to-processor mapping into an efficient full DRB mapping is presented     

Finding circular shapes in an image on a pyramid architecture

The problem of finding circular shapes in an image using a pyramid architecture is considered. In this paper we have defined a new transformation that converts circles in an image to a family of straight lines allowing the problem to be converted to line detection which can be solved by Hough transform algorithms. Also, based on this new transformation we have developed two algorithms for circle detection using a pyramid architecture.     

Comparison of PERSIANN and V7 TRMM Multi-satellite Precipitation Analysis (TMPA) products with rain gauge data over Iran

The objective of this research is to evaluate daily rain rates derived from three widely used high-resolution satellite precipitation products (PERSIANN, TMPA-3B42V7, and TMPA-3B42RT) using rain gauge observations over the entire country of Iran. Evaluations are implemented for 47 comprehensive daily rainfall events during the winter and spring seasons from 2003 to 2006. These events are selected because each encompasses more than 50% of the country’s area. In this study, daily rainfall observations derived from 1180 rain gauges distributed throughout the country are employed as reference surface data. Six statistical indices: bias, multiplicative bias (MBias), relative bias (RBias), mean absolute error (MAE), root mean square error (RMSE), and linear correlation coefficient (CC), as well as a contingency table are applied to evaluate the satellite rainfall estimates qualitatively. The spatially averaged results over the entire country indicate that 3B42V7, with an average bias value of –1.47 mmd^?1, RBias of –13.6%, MAE of 4.5 mmd^?1, RMSE of 6.5 mmd^?1, and CC of 0.61, leads to better estimates of daily precipitation than those of PERSIANN and 3B42RT. Furthermore, PERSIANN with an average MBias value of 0.56 tends to underestimate precipitation, while 3B42V7 and 3B42RT with average MBias values of 0.86 and 1.02, respectively, demonstrate a reasonable agreement in regard to rainfall estimations with the rain gauge data. With respect to the categorical verification technique implemented in this study, PERSIANN exhibits better results associated with the probability of detection of rainfall events; however, its false alarm ratio is worse than that of 3B42V7 and 3B42RT.