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(S)-Hydroxynitrile lyases from Hevea brasiliensis, Manihot esculenta, and Sorghum bicolor and (R)-hydroxynitrile lyase from Prunus amygdalus have been used as biocatalyst for the enantiospecific addition of hydrogen cyanide to aldehydes in organic solvents. The effects of the reaction parameters on the enzymatic reaction rate and product enantiomeric excess (e.e.) are presented. The reaction rate

A technique of continuous water activity control was used to examine the effects of water activity on enzyme catalysis in organic media. Esterification catalyzed by Rhizopus arrhizus lipase was preferably carried out at a water activity of 0.33, which resulted in both maximal initial reaction rate and a high yield. When Pseudomonas lipase was used as catalyst it was beneficial to start the reactio

Esterification of N-acetyl phenylalanine with ethanol catalyzed by immobilized αchymotrypsin (EC 3.4.21.1) was studied in various reaction media. The effect of reaction medium polarity on enzymatic activity as well as equilibrium yield was measured. The reaction rate increased with increasing amounts of added water, reaching an optimum corresponding to water saturation of the reaction medium. Furt

The ability of several electron acceptors to promote the Gluconobacter oxydans catalyzed oxidation of glycerol was investigated. p-Benzoquinone was the most effective electron acceptor. The reaction rate obtained with p-benzoquinone was higher than the maximal rate with the natural electron acceptor, oxygen, in all the oxidation reactions tested.

Models of baryon structure predict a small quadrupole deformation of the nucleon due to residual tensor forces between quarks or distortions from the pion cloud. Sensitivity to quark versus pion degrees of freedom occurs through the Q2 dependence of the magnetic (M1+), electric (E1+), and scalar (S1+) multipoles in the γ∗p→Δ+→pπ0 transition. We report new experimental values for the ratios E1+/M1+

We report the first results of the beam-spin asymmetry measured in the reaction →ep→epγ at a beam energy of 4.25 GeV. A large asymmetry with a sinφ modulation is observed, as predicted for the interference term of deeply virtual compton scattering (DVCS) and the Bethe-Heitler process. The amplitude of this modulation is α=0.202±0.028. In leading-order and leading-twist perturbative QCD, the α is d

Fundmental comprehension of light-induced processes in perovskites are still scarce. One active debate surrounds the influence of excess lead iodide (PbI2) on device performance, as well as optoelectronic properties, where both beneficial and detrimental traits have been reported. Here, we study its impact on charge carrier recombination kinetics by simultaneously acquiring the photoluminescence q

The last decade has seen an expansion in initiatives promoting the development of special sex services oriented to people with disabilities, which in Europe are increasingly labelled ‘sexual assistance’. These have become the object of political and media attention, and arguably call for a critical analysis incorporating both disability and sex workers’ rights perspectives. Based on an 18-month em

Summary: The longitudinal growth rates of the distal fibula were measured, using a roentgen stereophotogrammetric method, in 32 children treated for slipped capital femoral epiphysis and compared with growth rates in a series of normal children. The growth rates in patients were similar to the growth rates in normal children, in both boys and girls. However, at the time of slippage, 13 patients ha

The use of motor reactions including spinal motor mechanisms, such as tail-flick, hot plate test, and flexion reflexes, in research on pain and analgesia requires some precautions, and results should be interpreted with caution. Nocifensive specificity and analgesic selectivity cannot be established unequivocally by only comparing reflexes evoked by noxious stimuli with monosynaptic reflexes. Rath

Elasto plastic analysis was performed to determine the conditions at the root of a notch in a CERT specimen and the conditions at a crack growing in a CERT specimen. Furthermore. analysis of growth under small scale yielding was performed in order to facilitate analysis of compact tension specimen. By experiments it was shown how the stress strain conditions affect initiation of intergranular crac

Purpose: Low-risk prostate cancer is found in about half of newly diagnosed men subjected to PSA screening. Methods: To define the role of active surveillance and focal therapy in low- and intermediate-risk prostate cancers, an invited international panel of practicing physicians in the field of localized prostate cancer discussed the available literature in three consecutive meetings to come to a

The study was undertaken to prospectively evaluate a Streptococcus pneumoniae urinary antigen test for diagnosis of pneumococcal pneumonia among patient and control groups between 2004 and 2006. Microbiological analysis for these patients included Gram staining for sputum, sputum and blood culture. Nonconcentrated urine samples were tested using an immunochromatographic assay, the NOW S.pneumoniae

X-ray absorption spectroscopy is a powerful probe of molecular structure, but it has previously been too slow to track the earliest dynamics after photoexcitation. We investigated the ultrafast formation of the lowest quintet state of aqueous iron(II) tris(bipyridine) upon excitation of the singlet metal-to-ligand-charge-transfer ( 1