Photocatalytic hydrogen evolution from aqueous solutions of organophosphorous compounds

Photocatalytic hydrogen production from water solutions of dimethyl methylphosphonate (DMMP), trimethyl phosphate (TMP), triethyl phosphate (TEP), and radiation protective amine WR 2721, that imitate nerve chemical warfare agents was studied for the first time. Platinized titianium dioxide Degussa P25 was used as catalyst. No significant hydrogen evolution was detected without organic electron donors – sacrificial agents.     

The nature of the photochromism arising in the nanosized MoO3 films

We carried out the experiments which show unambiguously that not one, as it was commonly accepted, but three optical absorption bands corresponding to different color centers arise in the nanosized MoO₃ films due to hydrogen atoms. Varying the conditions for the photoinjection of hydrogen into the MoO₃ films, it is possible to change drastically the correlation between the concentrations of different arising centers, which in turn yields the great difference in the optical absorption spectra. Our findings are crucial for understanding of the nature of electrochromism and photochromism not only in MoO₃ films but also in the series of the transition metal oxide films.     

On design sensitivities in the structural analysis and optimization of flexible multibody systems

Multibody System Dynamics - The structural analysis and optimization of flexible multibody systems become more and more popular due to the ability to efficiently compute gradients using...     

Optical Detection of Phase Transformations in Steels: An Innovative Method for Time-Efficient Material Characterization During Tailored Thermo-mechanical Processing of a Press Hardening Steel

Metallurgical and Materials Transactions A - With an innovative optical characterization method, using high-temperature digital image correlation in combination with thermal imaging, the local...     

Nanoporous Gold Catalyst for the Oxidative N-Dealkylation of Drug Molecules: A Method for Synthesis of N-Dealkylated Metabolites

A novel method for the selective catalytic N-dealkylation of drug molecules on a nanoporous gold (NPG) catalyst producing valuable N-dealkylated metabolites and intermediates is described. Drug metabolites are important chemical entities at every stage of drug discovery and development, from exploratory discovery to clinical development, providing the safety profiles and the ADME (adsorption, distribution, metabolism, and elimination) of new drug candidates. Synthesis was carried out in aqueous solution at 80 °C using air (oxygen source) as oxidant, in single step with good isolated yields. Different examples examined in this study showed that aerobic catalytic N-dealkylation of drug molecules on NPG has a broad scope supporting N-deethylation, N-deisopropylation and N-demethylation, converting either 3° amines to 2° amines, or 2° amines to 1° amines.     

A targeted review of bio-derived plasticizers with flame retardant functionality used in PVC

Journal of Materials Science - For decades, a wide variety of products have benefitted from the use of flexible PVC, ranging from healthcare to cable to packaging & household items. The...     

Presence of women on the editorial boards of the language and linguistics journals in Spain

Scientometrics - Many international studies have pointed out the under-representation of women on Editorial Boards of both Science and Social Science journals. Their presence as Editorial Board...     

Recommender systems in the healthcare domain: state-of-the-art and research issues

Journal of Intelligent Information Systems - Nowadays, a vast amount of clinical data scattered across different sites on the Internet hinders users from finding helpful information for their...     

Chemical Zymogens: Specificity and Steroidal Control of Reactivation

Activating and masking enzymatic activity on demand is of the highest importance in nature. It is achieved by chemical interconversion of enzymes and the corresponding zymogens through, for example, proteolytic processing or reversible phosphorylation, and affords on-demand activation of enzymes, controlled in space and/or time. In stark contrast, examples of chemical zymogens are very few, and in most cases these are based on disulfide chemistry, which is largely indiscriminate as to the nature of the activating thiol. In this work, we address an outstanding challenge of specificity of reactivation of chemical zymogens. We achieve this through engineering affinity between the chemical zymogen and the activator. Additional, higher-level control over zymogen reactivation is installed in a nature-mimicking approach using steroidal hormones. Taken together, the results of this study take a step towards establishing the specificity of reactivation of synthetic, chemical zymogens. We anticipate that the results of this study will contribute significantly to the development of chemical zymogens as tools for diverse use in chemical biology and biotechnology.     

Oligonucleotides Containing C5-Propynyl Modified Arabinonucleic Acids: Synthesis,Biophysical and Antisense Properties

The introduction of chemical modifications on the nucleic acid scaffold has allowed for the progress of antisense oligonucleotides (ASOs) in the clinic for the treatment of a variety of disorders. In contribution to the repertoire of gene-silencing nucleic acid modifications, herein we report the synthesis and incorporation of C5-propynyl arabinouridine ( araU^P ) and arabinocytidine ( araC^P ) into mixed-base ASOs containing a pyrimidine core. Substitution of the core with araU ^P and araC^P resulted in stabilization of the duplex formed with RNA but not with DNA. Similar results were obtained with ASOs bearing phosphorothioate linkages or methoxyethyl (MOE) wings in a gapmer design. All modified ASOs were compatible with E. coli RNase H mediated degradation of target RNA. Substitution of DNA for araU^P and araC^P in the central portion of a gapmer with MOE wings demonstrated improved nuclease resistance. These results suggest C5-modified arabinonucleic acids may serve as a potential chemical modification for therapeutic ASOs.