The oxidation states in organic compounds

Presented is a method of assessment of the oxidation states of atoms in organic compounds. The method is a simple extension of the  Pauling´s electronegativity concept and is applied in various types of reactions including the biochemical processes of vital importance like neutralization of free radicals, β-oxidation or functioning of the nucleotide reductases

Optimisation of a nano-positioning stage for a Transverse Dynamic Force Microscope

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.This paper describes the optimisation of a nano-positioning stage for a Transverse Dynamic Force Microscope (TDFM). The nano-precision stage is required to move a specimen dish within a horizontal region of 1 μm × 1 μm and with a resolution of 0.3 nm. The design objective was to maximise positional accuracy during high speed actuation. This was achieved by minimising out-of-plane distortions and vibrations during actuation. Optimal performance was achieved through maximising out-of-plane stiffness through shape and material selection as well optimisation of the anchoring system. Several shape parameters were optimised including the shape of flexural beams and the shape of the dish holder. Physical prototype testing was an essential part of the design process to confirm the accuracy of modelling and also to reveal issues with manufacturing tolerances. An overall resonant frequency of 6 kHz was achieved allowing for a closed loop-control frequency of 1.73 kHz for precise horizontal motion control. This resonance represented a 12-fold increase from the original 500 Hz of a commercially available positioning stage. Experimental maximum out-of-plane distortions below the first resonance frequency were reduced from 0.3 μm for the first prototype to less than 0.05 μm for the final practical prototype

Constraints on and facilitators of young people’s participation: The case of border regions of mainland Portugal

Highlights: Young people are involved in diverse types of participation, being engaged, disengaged or unpolitical. Young people perceive opportunities to organise initiatives but not to participate in local decisions. Constraints on participation and responses to promote it were identified. Context-specific barriers were mentioned by young people and policymakers. Municipalities and schools are priority contexts for fostering youth participation. Purpose: This article aims to assess constraints on and facilitators of youth participation in rural border regions. Knowledge about regional participation of young people is useful for developing territorialised policies. Methodology: Using a mixed method approach designed in line with theories of civic and political participation and youth studies, we analysed responses from young people to a questionnaire (n = 3968) and interviews with policymakers (n = 36) and young people (n = 20). Findings: Young people are involved in diverse types of civic and political participation and perceive more opportunities to organise initiatives than to participate in local decision-making. Constraints on participation relate to the distance between politics, governance institutions and young people, weak strategies of municipalities, lack of youth organisations and mobility. Facilitators of participation include supporting youth-led activities or involving young people in local decisions. Research implications: the study contributes to understanding youth participation in rural regions

Ruthenium(II)-arene complexes with monodentate aminopyridine ligands: insights into redox stability, electronic structures and biological activity

Sherpa Romeo green journal. Permission to archive accepted author manuscript.The synthesis and spectroscopic characterization of four ruthenium(II) arene complexes with monodentate pyridine derivatives ([( 6–p-cymene)RuCl2L]: L = 2-aminopyridine, 2-methylaminopyridine, 2-benzylaminopyridine, and pyridine) are reported. Full characterization was undertaken using 1H and 13C NMR spectroscopy, vibrational and electronic spectroscopies and crystallography (2-methylaminopyridine derivative). UB3LYP//(6-31+G(d),SPK-DZCD) density functional theory calculations determined the molecular and electronic structures. Cyclic voltammetry determined a large electrochemical stability window (>2.2 V) extending well beyond the physiological E°. Interactions with CT-DNA and BSA, and activity against four cell lines (HeLa, B16F10, HEp-2 and Vero) were evaluated. The 2-methylaminopyridine shows weak cytotoxicity (IC50 = 346 molL-1) towards HeLa cells. All the complexes interact with DNA at relatively high concentrations as determined by UV-vis spectroscopic titration. Results of circular dichroism spectroscopy, ethidium bromide competition, fluorescence spectroscopy and DNA viscosity measurements identify electrostatic interactions between partly hydrolyzed cationic complexes and the phosphate backbone of DNA as the most likely interaction mode. Slower rates of hydrolysis may be the origin of lower cytotoxicity for 1 these complexesYe

Measurement of the cross-section for b-jets produced in association with a Z boson at root s=7 TeV with the ATLAS detector ATLAS Collaboration

A measurement is presented of the inclusive cross-section for b-jet production in association with a Z boson in pp collisions at a centre-of-mass energy of root s = 7 TeV. The analysis uses the data sample collected by the ATLAS experiment in 2010, corresponding to an integrated luminosity of approximately 36 pb(-1). The event selection requires a Z boson decaying into high P-T electrons or muons, and at least one b-jet, identified by its displaced vertex, with transverse momentum p(T) > 25 GeV and rapidity vertical bar y vertical bar < 2.1. After subtraction of background processes, the yield is extracted from the vertex mass distribution of the candidate b-jets. The ratio of this cross-section to the inclusive Z cross-section (the average number of b-jets per Z event) is also measured. Both results are found to be in good agreement with perturbative QCD predictions at next-to-leading order