Showing papers by "Autonomous University of Barcelona published in 1985"
TL;DR: The anaerobic zones of Lakes Cis6 and Vilar had mass developments of purple sulfur bacteria during summer 1982 and these phenomena point to the crucial role of light in the development of layers of phototrophic bacteria in stratified lakes.
Abstract: The anaerobic zones of Lakes Cis6 and Vilar (Banyoles karstic area, NE Spain) had mass developments of purple sulfur bacteria during summer 1982. In Lake Vilar, Chromatium spp. was dominant (up to 92% of the microbial biovolume). In Lake Ciso, the predominant microorganisms were Chromatium spp. (up to 7 1%) and another purple sulfur bacterium forming aggregates (20%). The bacterial layer could be divided according to the physiological state of the cells into a top part of maximal specific activity, a peak of maximal abundance, and a bottom part of inactive cells. The bacteria in the peak were predominantly limited by light; sulfide, phosphate, and acetate were not limiting in the middle of the day. The light limitation started at the depth having the maximal concentration of cells; the top of the layer appeared to be sulfide-limited. Specific contents of photopigments, elemental sulfur, and reserve polymers decreased from the top to the bottom of the bacterial layer. These phenomena point to the crucial role of light in the development of layers of phototrophic bacteria in stratified lakes.
193 citations
TL;DR: In this article, the authors examined the frequency of new chromosomal rearrangements, that appeared only in the progeny of hybrid individuals, and found that 30 times higher mutation frequency was found in hybrid males than in hybrid females.
Abstract: Introgression of a chromosome segment from Drosophila serido into the genome of its sibling D. buzzatii brought about the release of mutator potential in the hybrids. Mutator activity was determined by examining the frequency of new chromosomal rearrangements, that appeared only in the progeny of hybrid individuals. Mutation frequency was 30 times greater in the progeny of hybrid males than in that of hybrid females. There was a remarkable influence of the D. buzzatii genetic background on the frequency of production of these new rearrangements. The appearance of a new rearrangement did not depend on the genotype of the larva that bore it, but only on that of its hybrid progenitor. Among the new rearrangements there were inversions, translocations, and duplications. The number of translocations was significantly lower than that of inversions or duplications; this last type was the most frequently recorded. The distribution of the aberrations among the four major autosomes seemed to be homogeneous, although the total number of breakpoints was significantly greater in chromosome 4 than in the others. No rearrangement was found on the X chromosome. Breakpoints within three of the four affected autosomes were not randomly distributed.
180 citations
TL;DR: In this paper, the authors considered the restricted three-body problem for values of the Jacobi constant C near the value C 2 associated to the Euler critical point L 2, and derived asymptotical expressions of the invariant manifolds for C ≲ C 2 and μ ≳ 0.
150 citations
TL;DR: A modification of the IFCC methods for AST and ALT that simplifies the procedure is studied, which can use commercially available reagent kits and can be easily mechanised.
115 citations
TL;DR: In this paper, the authors used perlite with a nutrient solution and 0, 1, 2.5 and 5 ppm levels of Na2CrO4 and showed a significant decrease of top growth and chlorosis in trifoliated leaves.
Abstract: Bush beans (Phaseolus vulgaris L. cv Contender) were grown on perlite with nutrient solution and 0, 1, 2.5 and 5 ppm levels of Na2CrO4 Significant decrease of top growth and chlorosis in trifoliated leaves were observed for 2.5 and 5 ppm Cr, with Cr concentrations (μg/g) in tops:≥ 12.1, in roots:≥ 509.9. Cr decreased K, Na, Mg and Fe concentrations, and increased P and Mn concentrations in roots. In tops decreased N, K, Na and Fe concentrations and increased Mn and Ca concentrations were observed, Translocation of P, Zn, Cu and Fe was inhibited; Ca and Mn translocation was generally enhanced. P/Fe ratio was increased up to 60% in chlorotic plants, indicating a shift from Fe2+ to Fe3+.
91 citations
TL;DR: 230 patients with occupational dermatitis in I ho metallurgic industry were studied with standard patch tests (GEIDC) and an oil series and responses to paraphenylenediamine, chrome, cobalt, and benzisothiazolone, triethanolamine, and Grotan BK® were the main positive results.
Abstract: 230 patients with occupational dermatitis in I ho metallurgic industry were studied with standard patch tests (GEIDC) and an oil series. An occupational and clinical questionnaire survey was carried out, Responses to paraphenylenediamine, chrome, cobalt in the standard series, and benzisothiazolone, triethanolamine, and Grotan BK® were the main positive results.
88 citations
TL;DR: Percoll is a more suitable medium than sucrose to measure the density of live bacterial cells because of the high osmolarity of sucrose which gives artificial results.
Abstract: Accumulation of poly-β-hydroxybutyrate (PHB) was studied in Alcaligenes eutrophus strain N9A. Under nitrogen limitation and heterotrophic conditions, the cells accumulated PHB at a rate of 50 fg cell-1 h-1. Volume increased from 1.208 to 3.808 μm3 and buoyant density from 1.110 to 1.145 pg μm-3 with an increase in PHB from 0 up to 1.699 pg cell-1. Volume was found to change linearly with PHB content. The changes were due to increases in cell width and not in cell length. PHB explained 93% of the changes in cellular volume. The relationship between density and PHB was hyperbolic. PHB explained 96% of the changes in density. When a mutant strain unable to accumulate PHB was analyzed together with the wild type, the PHB-less mutant and the wild type showed densities of 1.100 pg μm-3 and 1.120 pg μm-3, respectively, in gradients of 65% Percoll. In sucrose gradients, nevertheless, the results were reversed. This discrepancy was explained by the high osmolarity of sucrose which gives artificial results. Thus, we conclude that Percoll is a more suitable medium than sucrose to measure the density of live bacterial cells.
81 citations
TL;DR: The Cabo Ortegal eclogites are allochthonous as mentioned in this paper, which is similar to present-day MORB sources, and they have been thrust up on to the continent and thus they can be compared to other ECLogites which also show MORB-like characteristics.
Abstract: REE abundances and Nd isotopic compositions were determined on representative samples of eclogite from the Cabo Ortegal Complex of northern Spain. Zircons were also separated from a whole-rock eclogite and analysed by the UPb radiometric method. Results indicate that eclogite facies metamorphism occurred between 480 and 420 Ma ago, but no precise constraint can be placed on the protolith age. The REE patterns observed suggest that there has been no significant alteration of the protolith whole-rock systems and that high-grade metamorphism has had little effect on the more mobile LREE. The eclogite protoliths were probably derived from ancient mantle sources with geochemical characteristics very similar to present-day MORB sources. This implies that LREE-depleted (N-type) tholeiites have been erupted at constructive plate margins since at least the early Palaeozoic and possibly long before. The Cabo Ortegal eclogites are allochthonous. They have been thrust up on to the continent and thus they can be compared to other eclogites which also show MORB-like characteristics (e.g., 90% of the eclogites of Vendee area of western France).
81 citations
TL;DR: The Malpica-Tuy (MT) unit is a narrow band of basement in Galicia (northwest Spain) composed of mica schists, paragneisses and calc-alkaline to peralkaline orthogneisses with minor amounts of metamorphosed basic rocks as discussed by the authors.
76 citations
TL;DR: The production of sugars by the enzymatic hydrolysis of cellulose is a two‐step process that includes conversion of the intermediate cellobiose to glucose by β‐glucosidase, which showed maximum activity at pH 4.8.
Abstract: The production of sugars by the enzymatic hydrolysis of cellulose is a two-step process that includes conversion of the intermediate cellobiose to glucose by beta-glucosidase. The hydrolysis was followed by analyzing the two sugar products (cellobiose and glucose). The enzyme showed maximum activity at pH 4.8. Thermal deactivation was significant at temperatures above 45 degrees C. At 50 degrees C (optimum temperature) thermal deactivation was found to follow first-order kinetics. Several models were tested by modeling the kinetics of the reaction. Their parameter values were determined by numerical optimization, including temperature dependence. The best fitting model was a competitive product inhibition for the two reactions in the operational range.
65 citations
TL;DR: The majority of measured variables attained a stable level within 3 hr, exceptions being pH and lactate, however, it is argued that even after 24 hr post-operation the fish were in a “stressed” condition.
TL;DR: In this article, the radiative corrections to the one-loop order of the electroweak parameters in N = 1 supersymmetry were investigated and the general conclusion was that one always ends up by finding a few hundred MeV maximal effect on the weak boson mass shifts, i.e., much smaller than the corresponding effect obtained in the standard model.
TL;DR: During a bloom of purple sulfur bacteria in Lake Ciso (Spain) data were collected on diel changes in the concentrations of sulfide, sulfur, glycogen, and poly-β-hydroxybutyrate, the rates of CO2 fixation and H2S oxidation, and the viability of cells along the vertical profile.
Abstract: During a bloom of purple sulfur bacteria in Lake Ciso (Spain) data were collected on diel changes in the concentrations of sulfide, sulfur, glycogen, and poly-β-hydroxybutyrate (PHB), the rates of CO2 fixation and H2S oxidation, and the viability of cells along the vertical profile. During the day, sulfide oxidation resulted in the intracellular accumulation of sulfur and glycogen. At night, the concentrations of glycogen and sulfur decreased concomitant with the production of sulfide and PHB. Throughout the day, CO2 fixation and H2S oxidation were maximal in the zone of maximal population density (peak of the layer); however, in the top of the layer the specific rates were 2–6 times higher. The ratio of CO2 fixation to H2S oxidation, the sulfur content of the cells, and their specific density all indicated that sulfide was predominantly oxidized to sulfur. In the top and the peak of the layer cell viability was high but decreased rapidly with increasing depth. It was concluded that the existence of the bloom is the combined result of slow growth at the peak of the layer and a much faster rate of reproduction at the top of the layer. The cells at the top stored sulfur extensively and then sank to deeper layers where they could not oxidize the sulfur because of insufficient light.
TL;DR: There was a marked reduction in anxiety during opioid detoxification, although subjects' experiences differed according to the drug used, and on the day of discharge, subjects who had received methadone still had attenuated withdrawal symptoms, whereas there were no such symptoms in the clonidine group.
Abstract: The efficacy of a rapid detoxification schedule (8 to 10 days) with clonidine or methadone was evaluated in 30 patients addicted to heroin. The dose of study drug was preestablished according to the subject's weight and the amount of opioid consumption, and the total daily dose was reduced by approximately 15% during the study. All subjects completed the detoxification program and stayed in the hospital for at least 12 days. Clonidine and methadone therapies proved to be highly effective. There was a marked reduction in anxiety during opioid detoxification, although subjects' experiences differed according to the drug used. On the day of discharge, subjects who had received methadone still had attenuated withdrawal symptoms, whereas there were no such symptoms in the clonidine group. Muscular aching, flatulence, and daily drowsiness were more common among subjects in the methadone group, while subjects in the clonidine group had more sleep disturbances and weeping. Syncopal episodes and bradycardia occurred more frequently in the clonidine group.
Clinical Pharmacology and Therapeutics (1985) 38, 336–341; doi:10.1038/clpt.1985.182
TL;DR: The so-called exponential model for the memory function of the transverse-velocity correlation function is derived under the assumptions of extended irreversible thermodynamics only and it is shown how more complicated memory functions can be derived.
Abstract: The thermodynamic implications of the first deviations with respect to the classical hydrodynamic behavior in high-frequency, short-wavelength phenomena are examined. The constitutive equations arising from an extended irreversible-thermodynamic formalism taking into account spatial inhomogeneities in the space of state variables are compared with those used in generalized hydrodynamics. The so-called exponential model for the memory function of the transverse-velocity correlation function is derived under the assumptions of extended irreversible thermodynamics only. Furthermore, it is also shown how more complicated memory functions can be derived. The results are carefully analyzed and compared with some microscopic derivations.
TL;DR: In this article, a model of low-energy physics with two supersymmetries was constructed and several mechanisms for providing large mirror fermion masses were given in models with gauge groups.
TL;DR: In this paper, a correlational study in a student sample was carried out to test the relationship between sensation seeking, as measured by the Sensation Seeking Scale (SSS) Form V, and antisocial behaviour, evaluated by a Self-reported Delinquency (SRD) scale, and the results obtained show, as predicted, a positive relationship between either the SSS Total score or its subscales, (Experience Seeking and Disinhibition) with the SRD.
TL;DR: Serum insulin levels were sensitive to both physiological and psychological stresses, forced swimming caused more marked glucose and insulin responses than noise exposure, chronic intermittent noise did not alter pancreatic function, and no sign of adaptation was apparent after repeated exposure to noise.
TL;DR: In this paper, very low power irradiation of suitable narrow peaks in the proton frequency range generated NOE enhancement in neighbouring quaternary carbons, positioned two bonds from the irradiated protons.
Abstract: Very low power irradiation of suitable narrow peaks in the proton frequency range generated NOE enhancement in neighbouring quaternary carbons, positioned two bonds from the irradiated protons. Subsequent FID acquisition under normal broad band decoupling yielded the NOE-containing FID, which, after subtraction of the unperturbed broad band decoupled FID (devoid of NOE), gave the final NOE difference FID to which only the carbons undergoing NOE enhancement had contributed. Fourier transformation of the latter gave the NOE difference spectrum, usually a one- or two-peak spectrum. This technique proved particularly useful for polysubstituted aromatic rings.
TL;DR: The frequency of Enterobacteriaceae strains which produce plasmid-mediated beta-lactamases is reported and the different types of betalactamase types are specified, somewhat higher than reported in the literature.
Abstract: Sir, We report on the frequency of Enterobacteriaceae strains which produce plasmid-mediated beta-lactamases and specify the different types of betalactamases. Six hundred and eighty Enterobacteriaceae were consecutively isolated from human pathological specimens by three clinical bacteriological laboratories in 1981-1982. All strains were identified by standard procedures. The MICs of arnpiciUin, amoxiciUin plus clavulanic acid (ratio 2 : 1) and eephalothin were determined for these strains on Mueller-Hinton agar using an inoculum of about 10 s CFU. According to a procedure published elsewhere (1), nitroeephin was added to disrupted bacteria to detect the presence of enzyme. The hydrolysis spectrum of the strains' overall beta-lactamase activity provided a rough substrate profile. The isoelectric point of the beta-lactamases was studied on poly. acrylamide gels by isoelectrofocusing (2, 3) using sonieated extracts that had been purified by ultrafiltration and concentrated when necessary. The betalactamase types were identified by comparison with standard enzymes (2, 3). Beta.lactamase activity was detected in 588 of the 680 strains: 270 showed cephalosporinase activity, 315 broad-spectrum enzyme activity and three, penieillinase activity. The 92 strains without activity included Salmonella spp. (14) and Proteus mirabilis (73). Three hundred and seventeen strains were susceptible to arnpicfllin; those having cephalosporinase activity alone or none at all were presumed to have only chromosome-mediated beta-lactamase. Three hundred and sixty-three (53.38 % of the total) were ampieillin-resistant (MIC > 16/ag/rnl); this ineluded all strains with broad-spectrum beta-Iactamase activity except one (314), plus 37 with cephalosporinase activity, three with penieillinase and nine without enzymatic activity. The isoeleetric point of the beta4actamases of all ampicillin-resistant strains was determined, in addition to that of four susceptible strains (one Escherichia coli with broad-spectrum activity, one Serratia spp., one Otrobacter spp. and one indole-positive Proteus spp.). Values were obtained for 340 strains (92.64 %); 297 of these showed plasmid-mediated beta-lactamase types and 43 showed only chromosome-mediated enzymes. In agreement with other publications (4, 5), the plasmid-mediated beta-lactamase encountered most frequently was TEM-I (87.54 % of the total strains, including those having one or two enzymes). The second most frequent was SHV-1 (in 14.81% of the total); this frequency is somewhat higher than reported in the literature (4, 5). In 19 strains two different types were identified. Two hundred and twenty-nine strains of Escherichia coli, Salmonella spp., Shighella spp. and Proteus mirabilis showed broad-spectrum beta-lactamase activity and all but one were ampicillin-resistant; 17.8% were resistant (MIC>16/~g/ml) to the combination amoxicillin + clavulanic acid and 30% to cephalothin (MIC > 16/ag/ml). Plasmid-mediated beta-lactamases were identified in 40.83 % of the strains, 97.33 % of which were TEM-1 type. The 57 strains of Klebsiella spp. were resistant to ampicillin, 27.27 % were resistant to amoxicillin + clavulanic acid and 32.8 % to cephalothin; broadspectrum activity was detected in 44 strains. Plasmidmediated beta-lactamases were identified in 73.68 % of these strains, SHV-1 (95.23 %) being the most frequent followed by TEM-1 (30.95 %); two different types were identified in 28.57 % of the strains. The frequency of plasmid-mediated beta-lactamases differs within the genus; whereas only one of 11 Klebsiella oxytoca strains carried plasmid-mediated betalactamases, 41 were observed in 43 Klebsiella pneumoniae strains.
TL;DR: In this paper, the effect of anomalous magnetic dipole and electric quadrupole moments of the charged weak boson on the muon anomaly was investigated and the constraints on those quantities derived from the experimental data were discussed.
TL;DR: In this paper, a sous-ensemble compact de C tel que C-X a un nombre fini de composantes connexes is considered, and a sens faible peut etre uniformement approche sur X par des fonctions ψ satisfaisant ∂(∂ψ/∂g)=0 dans un voisinage de X who satisfait ∂g(z)¬=0 ∀z∈x.
TL;DR: The numerical solution of the Maxwell-Bloch equations describing the propagation of a plane monochromatic wave through a saturable absorber shows the appearance of a new kind of reflected wave generated inside the medium.
Abstract: The numerical solution of the Maxwell-Bloch equations describing the propagation of a plane monochromatic wave through a saturable absorber shows the appearance of a new kind of reflected wave generated inside the medium This new phenomenon is described and its physical origin, related to the saturation-induced refractive index changes, is discussed
TL;DR: It is concluded that the condensation of DNA mediated by histone H1 is mainly due to its C-terminal domain, which is characterized by a nonconservative circular dichroism spectrum which is currently attributed to ordered aggregation of the DNA molecules.
TL;DR: The results suggest that crowding would be suitable as a model for chronic continuous stress and a dissociation between pituitary-adrenal responsiveness and behavioral measures presumably related to emotional arousal is suggested.
TL;DR: In this article, 25 different brominated derivatives of 4-hydroxy-6-methyl-2-pyrone (triacetic acid lactone) and 3-acetyl-4-hydrox-6 -methyl 2 pyrone have been described.
TL;DR: In this article, the transformation of organic matter during the composting process of ground barley straw and pear-tree wood was studied, and several parameters, such as the diversity index and pyrolysis ratios, were used to study the changes in the pyrograms during the process.
TL;DR: A Cd-, Zn-, Cu-binding protein was isolated from the liver of dogfish subjected to environmental experimental contamination and found in liver from untreated fish, suggesting a mercaptide bond and a lack of aromatic amino acids.