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On the stepwise change of activation energies in the hydrodechlorination of chlorobenzene over supported nickel

Kinetics of chlorobenzene hydrodechlorination have been measured over Ni on SiO2, Al2O3, MgO, activated carbon and graphite. A stepwise variation of E-a is analysed using the selective energy transfer model where E-a is identified as the vibrational energy associated with an excitation of the chlorobenzene out-of-plane C-H bending mode. Variation of E-a with vibrational quantum number yields a vib

Applying biochemical and physiological principles in the industrial freezing of vegetables: a case study on carrots

We review here the potential benefits of metabolic changes in carrots upon cold stress, a process known as cold acclimation, for the enhancement of quality upon freezing. The damaging action of a previous blanching operation is discussed and the alternative of using mild blanching treatments to minimise tissue damage is reviewed. Blanching treatments, aimed at inactivating enzymes near the surface

A proteomic method for the analysis of changes in protein concentrations in response to systemic perturbations using metabolic incorporation of stable isotopes and mass spectrometry

While several techniques exist for assessing quantitative differences among proteomes representing different cell states, methods for assessing how these differences are mediated are largely missing. We present a method that allows one to differentiate between cellular processes, such as protein synthesis, degradation and PTMs which affect protein concentrations. An induced systemic perturbation o

Endocytotic activity of mouse skeletal muscle fibres after long-term denervation

The endocytotic activity of skeletal muscle fibres and its relation to the denervated endplate region has been studied using horseradish peroxidase (HRP) as marker for endocytosis. In muscles denervated for a short time period (10-20 days) HRP-uptake occurred in small segments of the muscle fibres near the centre of the muscle (endplate region). After long-term denervation (6-12 months) similar se

Nitric oxide-dependent processing of heparan sulfate in recycling S-nitrosylated glypican-1 takes place in caveolin-1 containing endosomes.

We have previously demonstrated intracellular degradation of the heparan sulfate side-chains in recycling glypican-1 by heparanase and by deaminative cleavage at N-unsubstituted glucosamine with nitric oxide derived from intrinsic nitrosothiols [see Ding, K., Mani, K., Cheng, F., Belting, M. and Fransson, L.-. (2002) J. Biol. Chem., 277, xxx-xxx; prepub M203383200]. To determine where and in what

Lipopolysaccharide-induced gelatinase granule mobilization primes neutrophils for activation by galectin-3 and formylmethionyl-Leu-Phe

We have earlier shown that galectin-3, a lactose-binding mammalian lectin that is secreted from activated macrophages, basophils, and mast cells, induces activation of the NADPH oxidase in exudated but not in peripheral blood neutrophils (A. Karlsson, P. Follin, H. Leffler, and C. Dahlgren, Blood 91:3430-3438, 1998). The alteration in responsiveness occurring during extravasation correlated with m

Euro50

The Euro50 is a telescope for optical and infrared wavelengths. It has an aspherical primary mirror with a size of 50 meters and 618 segments. The optical configuration is of Gregorian type and the secondary mirror is deformable for adaptive optics. Observations can take place in prime focus, Gregorian foci, and Nasmyth foci using additional relay mirrors. The telescope provides seeing limited obs

The direct effects of UV-B radiation on Betula pubescens litter decomposing at four European field sites

A co-ordinated series of field experiments were conducted to consider the effects of elevated UV-B radiation applied directly to decomposing plant litter. Betula pubescens was decomposed under ambient and elevated UV-B (simulating a 15% ozone depletion) using outdoor irradiation facilities at Adventdalen, Norway (78° N), Abisko, Sweden (68° N), Amsterdam, The Netherlands (52° N,) and Patras, Greec

Improving the pathogenicity of a nematode-trapping fungus by genetic engineering of a subtilisin with nematotoxic activity.

Nematophagous fungi are soil-living fungi that are used as biological control agents of plant and animal parasitic nematodes. Their potential could be improved by genetic engineering, but the lack of information about the molecular background of the infection has precluded this development. In this paper we report that a subtilisin-like extracellular serine protease designated PII is an important

Does risk of intraspecific interactions induce shifts in prey-size preference in aquatic: predators?

Interactions between foragers may seriously affect individual foraging efficiency. In a laboratory study of handling time, prey value and prey-size prefer ence in northern pike and signal crayfish, we show that risk of intraspecific interactions between predators does not affect handling time or value of prey. However, the presence of agonistic intraspecific interactors shifts prey-size preference

An approach for on-line cutting edge stress estimation

Cutting edge deteriorations are attributed to higher mechanical and thermal stresses working on it during metal cutting. However, the stress estimation is a difficult task, especially when on-line estimation is desired. This paper presents a new approach for cutting edge mechanical stress estimation and load simulation. The approach can be applied in the implementation of on-line stress estimation

Stabilization of internal charges in a protein: Water penetration or conformational change?

The ionizable amino acid side chains of proteins are usually located at the surface. However, in some proteins an ionizable group is embedded in an apolar internal region. Such buried ionizable groups destabilize the protein and may trigger conformational changes in response to pH variations. Because of the prohibitive energetic cost of transferring a charged group from water to an apolar medium,

Circulating cell adhesion molecules in bronchial lavage and serum in COPD patients with chronic bronchitis

The initial phase of inflammation in bronchial asthma appears to be triggered by the expression of leucocyte-endothelial adhesion molecules on endothelial cell surfaces. Cell adhesion molecules (CAMs) cause adhesion of leucocytes to the endothelium prior to their subsequent extravasation into inflamed tissue. We wanted to determine whether circulating intercellular adhesion molecule-1 (cICAM-1) an

Effect of endurance flight on haematocrit in migrating birds

The effects of an endurance flight on the haematocrit, the percentage of packed red blood cells per blood volume, were examined within the framework of six possible factors explaining possible changes in the haematocrit. Two approaches were adopted: (1) the haematocrit was studied in four species of passerine birds which landed on an Italian island after having crossed the Mediterranean Sea on the