Search results for "trains"
showing 10 items of 600 documents
Technostress and social networking services: Explaining users' concentration, sleep, identity, and social relation problems
2018
It is common for users of social networking sites and services (SNS) to suffer from technostress and the various associated strains that hinder their well‐being. Despite prior SNS stress studies having provided valuable knowledge regarding SNS stressors and their use consequences, they have not examined the various strains related to well‐being that those stressors can create nor the underlying SNS characteristics. To address this gap in the research, we used a qualitative approach involving narrative interviews. As a contribution, our findings reveal four types of strains related to well‐being (concentration problems, sleep problems, identity problems, and social relation problems) as well…
Vibriosis in aquaculture. 16th EAFP Conference, Tampere, Finland, 4th September 2013
2014
Aquaculture in brackish and marine water is growing worldwide (FAO, 2014), including new cultured species. Various Vibrio infections occur, and cause significant problems, in fish, crustacean and shellfish (Austin & Austin, 2007. Vibrio anguillarum, V. salmonicida, V. ordalii and V. vulnificus are among the pathogens that lead to the biggest losses in aquaculture all over the world (Toranzo et al. 2005, Sandlund et al., 2010; Sitjà-Bobadilla et al. 2014).
On the fermentative behavior of auxotrophic strains of Saccharomyces cerevisiae
2014
Background: The selection of new yeast strains could lead to improvements in bioethanol production. Here, we have studied the fermentative capacity of different auxotrophic mutants of Saccharomyces cerevisiae, which are routinely used as hosts for the production of heterologous proteins. It has recently been found that these strains exhibit physiological alterations and peculiar sensitivities with respect to the parental prototrophic strains from which they derive. In this work the performance of auxotrophic S. cerevisiae CEN.PK strains was compared to the corresponding prototrophic strain, to S. cerevisiae T5bV, a strain isolated from grape must and to another auxotrophic strain, S. cerevi…
Absorption and intestinal catabolism of fatty acids in the rat: effect of chain length and unsaturation
1991
Simultaneous portal blood absorption and intestinal mucosal catabolism of labelled fatty acids were investigated. Anaesthetized adult Wistar rats were infused intraduodenally either with 90 mumol of capric (C10:0), oleic (C18:1), linoleic (C18:2) or arachidonic (C20:4) 1-14C acids or with 30 mumol of each labelled fatty acid in addition to 30 mumol of oleic acid and 30 mumol of monopalmitin. For mixed infusates, experiments were carried out with two additional long-chain fatty acids: palmitic (C16:0) and erucic (C22:1) 1-14C acids. Radioactivity was quantified in the lipids and in the catabolic products in portal blood recovered at 5 min intervals for 1 h after infusion. At the end of the e…
Effects of electrical stimulation pattern on quadriceps isometric force and fatigue in individuals with spinal cord injury
2015
Introduction Variable frequency trains (VFT) or train combinations have been suggested as useful strategies to offset the rapid fatigue induced by constant frequency trains (CFT) during electrical stimulation. However, most studies have been of short duration with limited functional application in those with spinal cord injury (SCI). We therefore tested force and fatigue in response to VFT, CFT, and combined patterns in strength training-like conditions (6-s contractions). Methods Ten SCI individuals underwent either CFT or VFT patterns until target torque was no longer produced and then switched immediately to the other pattern. Results Target torque was reached more times when VFT was use…
Tenascin gene expression in rat liver and in rat liver cells. In vivo and in vitro studies.
1991
Tenascin is a major glycoprotein constituent of the extracellular matrix with a strong affinity to fibronectin; its distribution is believed to be temporarily and spatially limited. Tenascin gene expression is increased during wound healing processes. As repair mechanisms in chronic liver diseases resemble wound healing we studied tenascin gene expression in rat liver and in isolated rat liver cells. In normal rat liver a tenascin specific antiserum stains sinusoidal cells with fiber-like prolongations, which at the same time are desmin-positive (ITO-cells). In the CCl4-acutely-damaged liver a strong tenascin staining is detected in cells located among the mononuclear cells of the inflammat…
Effects of LHRH, progesterone, estradiol-17 ? and dexamethasone in vitro on pineal synaptic ribbons and serotonin N-acetyltransferase activity in die…
1991
Pineal glands of regularly cycling Sprague Dawley rats (180-220 g) killed on the diestrous morning (between 0900-1000 h) were incubated in appropriate media for six hours with LHRH (8.5 microM), progesterone (3.2 microM), estradiol-17 beta (370 nM) or dexamethasone (250 nM). Pineals incubated in hormone-free medium and unincubated glands served as controls. Six rats were used in each group. After incubation the glands were divided into two parts. One part was used to estimate serotonin N-acetyltransferase (NAT) activity. The other part was processed for electron microscopy to quantify synaptic ribbons (SR). The SR numbers were computed to 20,000 microns 2 area of pineal tissue. The number a…
Effects of sulphonylureas on spontaneous motility and induced contractions in rat isolated uterus
1986
Abstract To clarify the action of sulphonylureas on calcium, the effect of tolbutamide and ghbenclamide has been investigated on a Ca-dependent process, the contractile activity of uterine smooth muscle. Both sulphonylureas antagonized the contractions evoked by CaCl2 in a non-competitive manner when the uterus was maintained in depolarizing solution and did not affect the spontaneous contractions of rat uterus. The capacity of tolbutamide and ghbenclamide to relax vanadate-induced contraction of rat uterus in Ca-free medium suggests that sulphonylureas may have an intracellular site of action related to cytosolic free Ca levels, or effect a reduction in Ca action.
In vitro synthesis of dopamine and noradrenaline in the isolated rat pineal gland: day-night variations and effects of electrical stimulation.
1989
: Isolated rat pineal glands were incubated in vitro in a medium containing [I4C]dopamine or [14C]tyrosine, and the tissue contents of l4C-labelled and total dopamine and noradrenaline were determined by HPLC followed by electrochemical detection and scintillation spectrometry. During incubation with [l4C]dopamine, the labelled amine accumulated in pineal glands and was partially converted into [l4C]noradrenaline. Nomifensine, a neuronal amine uptake blocker, largely inhibited the accumulation of [l4C]dopamine and the formation of [14C]noradrenaline. These experiments demonstrated dopamine β-hydroxylase activity in the sympathetic nerves of the pineal gland. During incubation with [14C]tyro…
Depressive effect of LHRH on the numbers of "synaptic" ribbons and spherules in the pineal gland of diestrous rats.
1983
Previous studies have shown that LHRH or LHRH-like substances are present in the pineal gland. In order to investigate whether exogenous LHRH may affect the pineal gland, in the present study the effects of a single dose of LHRH (1 microgram, i.p.) on pineal "synaptic" ribbons and spherules as well as serum melatonin levels were examined in diestrous Wistar rats. One hour after the injection both ribbons and spherules exhibited a statistically significant decrease in number. Serum melatonin levels were not affected. It is concluded that humoral feedback mechanisms may exist between the hypothalamus and the pineal gland.