Restricted migration of reactive species limits chemical transformations within interstellar and cometary ices. We report the migration of CO2 from clathrate hydrate (CH) cages to amorphous solid water (ASW) in the presence of tetrahydrofuran (THF) under ultrahigh vacuum (UHV) and cryogenic conditions. Thermal annealing of sequentially deposited CO2 and H2O ice, CO2@H2O, to 90 K resulted in the partitioning of CO2 in 512 and 51262 CH cages (CO2@512, CO2@51262). However, upon preparing a composite ice film composed of CO2@512, CO2@51262 and THF distributed in the water matrix at 90 K, and annealing the mixture for 6 h at 130 K produced mixed CO2–THF CH, where THF occupied the 51264 cages (THF@51264) exclusively while CO2 in 51262 cages (CO2@51262) got transferred to the ASW matrix and CO2 in the 512 cages (CO2@512) remained as is. This cage–matrix exchange may create a more conducive environment for chemical transformations in interstellar environments.

◥Agents targeting metabolic pathways form the backbone of standard oncology treatments, though a better understanding of differential metabolic dependencies could instruct more rationale-based therapeutic approaches. We performed a chemical biology screen that revealed a strong enrichment in sensitivity to a novel dihydroorotate dehydrogenase (DHODH) inhibitor, AG-636, in cancer cell lines of hematologic versus solid tumor origin. Differential AG-636 activity translated to the in vivo setting, with complete tumor regression observed in a lymphoma model. Dissection of the relationship between uridine avail-ability and response to AG-636 revealed a divergent ability of lymphoma and solid tumor cell lines to survive and grow in the setting of depleted extracellular uridine and DHODH inhibition. Metabolic characterization paired with unbiased functional genomic and proteomic screens pointed to adaptive mechanisms to cope with nucleotide stress as contributing to response to AG-636. These findings support targeting of DHODH in lymphoma and other hematologic malignancies and suggest combination strategies aimed at interfering with DNAdamage response pathways.

Nowadays, a huge amount of digital data is frequently changed among different embedded devices over wireless communication technologies. Data security is considered an important parameter for avoiding information loss and preventing cyber-crimes. This research article details the low power high-speed hardware architectures for the efficient field programmable gate array (FPGA) implementation of the advanced encryption standard (AES) algorithm to provide data security. This work does not depend on the look up tables (LUTs) for the implementation the SubBytes and InvSubBytes stages of transformations of the AES encryption and decryption; this new architecture uses combinational logical circuits for implementing SubBytes and InvSubBytes transformation. Due to the elimination of LUTs, unwanted delays are eliminated in this architecture and a subpipelining structure is introduced for improving the speed of the AES algorithm. Here, modified positive polarity reed muller (MPPRM) architecture is inserted to reduce the total hardware requirements, and comparisons are made with different implementations. With MPPRM architecture introduced in SubBytes stages, an efficient mixcolumn and invmixcolumn architecture that is suited to subpipelined round units is added. The performances of the proposed AES-MPPRM architecture is analyzed in terms of number of slice registers, flip flops, number of slice LUTs, number of logical elements, slices, bonded IOB, operating frequency and delay. There are five different AES architectures including LAES, AES-CTR, AES-CFA, AES-BSRD, and AES-EMCBE. The LUT of the AES-MPPRM architecture designed in the Spartan 6 is reduced up to 15.45% when compared to the AES-BSRD.

No abstract

No abstract