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Complex formation between Pd(H2O)(4)(2+) and maleic acid (H(2)A) has been studied at 25 degrees C and 2.00 M ionic strength in acidic aqueous solution. Reaction takes place with 1:1 stoichiometry. The kinetics has been followed by use of stopped-flow spectrophotometry under pseudo-first-order conditions with maleic acid in excess. In the concentration ranges 0.01 less than or equal to [H(2)A](tot)

SynopsisOn the basis of kinetic studies of the manganese-catalyzed autoxidation of sulfite and thermodynamic data for iron−manganese redox processes and manganese(II) and -(III) protolysis equilibria, the catalytically active species in the autoxidation is concluded to be a mixed-valence oxo-bridged manganese(II,III) complex. Iron−manganese synergism and triggering of the chain reaction by small c

Reduction of trans-[Pt(CN)(4)Cl-2](2-) by [Pt(NH3)(4)](2+) and [Pt(en)(2)](2+) was studied at 25 degrees C in the range 0 less than or equal to [Cl-] less than or equal to 0.4 M by use of stopped-flow spectrophotometry. The stoichiometry [Pt(IV)]:[Pt(II)] is 1:1. Rapid-scan spectra show clear-cut isosbestic points, indicating that no reaction intermediates are accumulated to a significant amount.

Reactions of 4-thio-2′-deoxyuridine d(s4U) and 4-thiouridine 5′-monophosphate s4UMP with trans-[AuY2Cl2]+/– (Y = CN– or NH3) have been investigated by conventional and high-pressure stopped-flow spectrophotometry in aqueous solution with 2.9 ⩽ pH ⩽ 7.0. For a given combination of metal complex and sulfur donor the observed second-order rate constants decreased with increasing pH. In the pH range 2

Deoxyribonucleoside kinases (dNKs) salvage deoxyribonucleosides (dNs) and catalyze the rate limiting step of this salvage pathway by converting dNs into corresponding monophosphate forms. These enzymes serve as an excellent model to study duplicated genes and their evolutionary history. So far, among vertebrates only four mammalian dNKs have been studied for their substrate specificity and kinetic

Objective Although depression among older people is an important public health problem worldwide, systematic studies evaluating its prevalence and determinants in low and middle income countries (LMICs) are sparse. The biopsychosocial model of depression and prevailing socioeconomic hardships for older people in LMICs have provided the impetus to determine the prevalence of geriatric depression; t

En kort text om James Hargreaves

Certain pesticides may affect children's neurodevelopment. We assessed whether pesticide exposure was associated with impaired neurobehavioral outcomes in children aged 6–9 years. We conducted a cross-sectional study in 140 children living near banana plantations and plantain farms in the Talamanca County, Costa Rica and assessed their neurobehavioral performance. Exposure was determined by analyz

Bacterial plasmids are extensively involved in the rapid global spread of antibiotic resistance. We here present an assay, based on optical DNA mapping of single plasmids in nanofluidic channels, which provides detailed information about the plasmids present in a bacterial isolate. In a single experiment, we obtain the number of different plasmids in the sample, the size of each plasmid, an optica

Context: The androgen receptor (AR) gene exon 1 CAG repeat length has been proposed to be a determinant of between-individual variations in androgen action in target tissues, which might regulate phenotypic differences of human ageing. However, findings on its phenotypic effects are inconclusive. Objective: To assess whether the AR CAG repeat length is associated with longitudinal changes in endpo

Background: The contribution of smoking to rheumatoid arthritis (RA) is hypothesized to be mediated through formation of anti-citrullinated protein antibodies (ACPA). In RA, however, autoantibodies such as ACPA, rheumatoid factor (RF), and anti-carbamylated protein antibodies (anti-CarP) often occur together, and it is thus unclear whether smoking is specifically associated with some autoantibodie

Flowing fluid electrical conductivity (FFEC) logging is a hydrogeologic testing method that is usually conducted in an existing borehole. However, for the 2,500-m deep COSC-1 borehole, drilled at Åre, central Sweden, it was done within the drilling period during a scheduled 1-day break, thus having a negligible impact on the drilling schedule, yet providing important information on depths of hydra