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Kinetic investigation of a PC(sp(3))P pincer palladium (II) complex in the Heck reaction

An investigation of the kinetics of the Heck reaction between 4-iodoanisole and styrene catalysed by {cis-1,3-bis[(di-tert-butylphosphino)methyl]-cyclohexane} palladium (11) iodide (1) has been performed in DMF-d(7) solution. Based on mercury poisoning experiments a heterogeneous palladium catalyst formed from the PCsp3P Pd(II) pre-catalyst is proposed. Saturation behaviour with respect to the ole

Blood redistribution in the fetal brain during chronic hypoxia

Background Studies on blood flow velocity in the fetal middle cerebral artery have revealed signs of brain sparing in chronic hypoxia. These signs of brain sparing can disappear in the terminal case, but whether this applies to the whole brain or only parts of it is unknown. Methods Velocity waveforms of the middle cerebral, anterior cerebral and posterior cerebral arteries were recorded in 221 pr

Role of stray light in the formation of high-resolution resonant photoelectron spectra: an experimental and theoretical study of N-2

We show that the undular stray light, diffusely scattered by the optical system of a synchrotron beamline, can play an important role in the formation of high-resolution resonant photoelectron (RPE) spectra. The influence of the stray light is mediated through the Stokes doubling effect, with the Lorentzian tail of the spectral function being replaced by a more complicated form. This effect is sho

Activation of Ca(2+)-dependent K(+) channels contributes to rhythmic firing of action potentials in mouse pancreatic beta cells

We have applied the perforated patch whole-cell technique to beta cells within intact pancreatic islets to identify the current underlying the glucose-induced rhythmic firing of action potentials. Trains of depolarizations (to simulate glucose-induced electrical activity) resulted in the gradual (time constant: 2.3 s) development of a small (60%) blocked by high (10-20 mM) concentrations of tetrae

Immune tolerance induction and the treatment of hemophilia. Malmo protocol update

The Malmo protocol for immune tolerance induction includes high doses of Factor VIII/IX, intravenous IgG and cyclophosphamide. If the inhibitor titer exceeds 10 Bethesda units at start, extracorporeal adsorption of IgG is performed using protein A. The protocol sometimes has to be repeated. A successful response may occur within a few weeks. In hemophilia A the success rate so far is 10/17 patient

Effects of Tolterodine on Afferent Neurotransmission in Normal and Resiniferatoxin Treated Conscious Rats.

Purpose: The beneficial effects of antimuscarinics on detrusor overactivity and overactive bladder syndrome are exerted during bladder filling, when there is no parasympathetic outflow from the spinal cord. We tested the hypothesis that, if tolterodine exerts some of its effects on afferent nerves, the functional elimination of C-fiber afferents should affect the actions of the drug on urodynamic

Performance analysis of general charge sampling

This brief focuses on the performance analysis of general charge-sampling circuits for signal capture. The theoretical analysis in the brief can be applied not only for weak signal capture, but also for the normal signal sampling. Based on a general charge-sampling model, the transfer function, the noise performance, and the clock jitter tolerance are analyzed and compared to conventional voltage

A model on the evolution of cryptobiosis

Cryptobiosis is an ametabolic state of life entered by some lower organisms (among metazoans mainly rotifers, tardigrades and nematodes) in response to adverse environmental conditions. Despite a long recognition of cryptobiotic organisms, the evolutionary origin and life history consequences of this biological phenomenon have remained unexplored. We present one of the first theoretical models on

An Integrated System-On-Chip Test Framework

In this paper we propose a framework for the testing of system-on-chip (SOC), which includes a set of design algorithms to deal with test scheduling, test access mechanism design, test sets selection, test parallelization, and test resource placement. The approach minimizes the test application time and the cost of the test access mechanism while considering constraints on tests, power consumption

Glaucoma detection by Stratus OCT

Purpose: To investigate the diagnostic accuracy of retinal nerve fiber layer thickness (RNFLT) summary report parameters from Stratus optical coherence tomography (OCT) in glaucoma patients. Patients and Methods: We obtained Stratus OCT measurements of peripapillary circle scans (average values) of the regular image resolution "FAST RNFLT" protocol, and of 1 circle scan of the high resolution "RNF

Carbon cycling in subarctic tundra; seasonal variation in ecosystem partitioning based on in situ 14C pulse-labelling

Carbon assimilation and allocation were studied in a tundra ecosystem in northern Scandinavia. Seasonal variation in the below-ground carbon allocation to dissolved organic carbon (DOC), coarse-, fine-, and hair roots was investigated using in situ C-14 pulse-labelling, adding 2-3 MBq (CO2)-C-14, dm(-2) to the above-ground vegetation. Combining the allocation data with regression models of the sea

Common variants in the ENPP1 gene are not reproducibly associated with diabetes or obesity

The common missense single nucleotide polymorphism (SNP) K121Q in the ectoenzyme nucleotide pyrophosphate phosphodiesterase (ENPP1) gene has recently been associated with type 2 diabetes in Italian, U.S., and South-Asian populations. A three-SNP haplotype, including K121Q, has also been associated with obesity and type 2 diabetes in French and Austrian populations. We set out to confirm these find

Interactions between Sulfide Minerals and Alkylxanthate Ions .1. A Vibrational Spectroscopic Study of the Interactions between Sphalerite and Synthetic Zinc(Ii) and Cadmium(Ii) Sulfides, and Ethylxanthate Ions in Aqueous and Acetone Solutions

The crystal structures of zinc(II) and cadmium(II) sulphides are not affected by the stoichiometry of metal and sulphide ions at the precipitation of the two compounds. The composition and structure of the ultimate surface layers, and thereby the chemical properties of the particles, are on the other hand sensitive to the stoichiometry at the preparation. Chemisorbed ethylxanthate complexes are fo