Showing papers by "University of Barcelona published in 1974"
TL;DR: Hematological data were analysed in great flying birds, aquaticdiving birds and galliformes and the values with significant differences were lactic acid, erythrocyte number, hematocrit and the amount of hemoglobin.
70 citations
TL;DR: Using a new technique to stain and count planarian mitotic cells, a very rapid increase in neoblast mitotic activity has been found following feeding, suggesting that a substantial proportion of neoblasts in the intact worm must be in the G2 phase ready to enter mitosis.
Abstract: Using a new technique to stain and count planarian mitotic cells, a very rapid increase in neoblast mitotic activity has been found following feeding. The increase becomes visible 1 hour after feeding, reaches a maximum in 3–8 hours, and lasts for almost a week. These results suggest that a substantial proportion of neoblasts in the intact worm must be in the G2 phase ready to enter mitosis. The fact that the mitotic figures occur throughout the parenchyma also suggests that the stimulus may be of a neurohumoral kind.
56 citations
TL;DR: In this article, a review of the C 6 Cl 6 infrared spectrum is made and some combination bands observed in this spectrum are assigned and band assignments for some new compounds of the [MX (C 6 Cl 5 )(PPh 3 ) type (with M = Ni, Pd; X = C1, Br, I, NCS, NCO, N 3 ) are proposed.
52 citations
TL;DR: The amount of algal chlorophyll on the mud surface of a salt marsh was not affected directly by additions of urea or sewage sludge fertilizer but was proportional to light reaching the surface, and the quantity exceeded the amount found in other productive marine ecosystems.
45 citations
TL;DR: A variety of reasons support the conclusion that the polymorphism in the islands is a relict polymorphism, corresponding to a less evolved stage than the one present in the mainland.
Abstract: The level of chromosomal inversion polymorphism is much higher in three populations from South Morocco than in the nearby Canary and Madeira Islands. The composition of the chromosomal arrangements is also strikingly different in both areas. The similarity among the populations from the islands excludes drift or the founder principle as an explanation of these differences. A variety of reasons support the conclusion that the polymorphism in the islands is a relict polymorphism, corresponding to a less evolved stage than the one present in the mainland. The populations from South Morocco have a relatively low index of free recombination, like others from the southern range of the distribution ofD. subobscura. This contrasts with the high values found in the northern range. The populations from the North are relatively recently established ones, whereas those from the South are longer established and have become marginal only in relatively recent times. This difference in evolutionary history is sufficient to explain the differences in the index of free recombination.
39 citations
TL;DR: In this article, the quantum mechanics of the relativistic material point is discussed in the light of some recent ideas developed for the study of the interacting string model, and the interaction among the particles is introduced in a geometrical way, but also show how to interpret such an interaction as due to an external field.
Abstract: The quantum mechanics of the relativistic material point is discussed in the light of some recent ideas, developed for the study of the interacting string model. In accordance with these ideas the interaction among the particles is introduced in a geometrical way, but we also show how to interpret such an interaction as due to an external field. The same considerations are briefly applied to the string model.
38 citations
TL;DR: In this paper, the authors calculated the correction to the energy levels of the ion (μ4He)+ due to the two-phonon exchange mechanism and found that the hadronic contribution to the 2S-2P separation is ∼ 16A which is about three times larger than the expected experimental uncertainty.
34 citations
TL;DR: In this article, the authors show that the azide is the only stable polyazole in N-acetyl and N-H derivatives under neutral conditions, and that 3-azido-3 pyrazoles are the only polyazoles in which coupling with the n-H in NMR is observed.
31 citations
TL;DR: Azo derivatives prepared by coupling 2-diazoimidazole, 3(5))diazopyrazole, 4(5)diazotetrazole with β-naphthol have been cyclized to the corresponding naphthoazolo-as-triazines, an heterocyclic system related to azasteroids as mentioned in this paper.
22 citations
TL;DR: In this paper, high-energy collisions of hadrons on nuclei are studied by means of Glauber multiple scattering theory, using Jastrow correlated wave functions, and a cluster expansion is derived, and its convergence properties are studied.
12 citations
TL;DR: In this paper, the authors detected glutamate excretion by colonies of Citrobacter intermedium C3 by using the auxotrophic strain Leuconostoc mesenteroides P-60.
Abstract: Glutamate excretion by colonies of Citrobacter intermedium C3 was detected by using the auxotrophic strain Leuconostoc mesenteroides P-60. A constant ratio of strain C3 colonies did not excrete glutamate. These colonies were subcultured, and colonial analysis of their descendants established that the change from non-excretor to excretor (Sg− → Sg+) is a spontaneous and random process with occurs at a high rate, and that an equilibrium state results from the back-transition Sg+ → Sg− in large populations. Acridine orange, ethidium bromide, and shaking have a strong influence on Sg+-to-Sg− interconversion, which suggests that a genetic element like an episome is implicated (S factor). Various auxotrophic mutants of bacterial strain C3 have been cured of the S factor. Strains lacking the S factor (S− strains) do not excrete glutamate and lose their fermentative metabolism completely. Consequently, the S factor is different from other extrachromosomal genetic factors whose elimination does not modify central metabolism. The gain of the S factor by infectious transfer has been shown with different C3 auxotrophic mutant strains. Also, the S factor has been transferred to Paracolobactrum intermedium ATCC 11606. These findings suggest that phenotypic changes observed are a consequence of elimination or infectious gain of the S factor, with its autonomous or integrated multiplication.
TL;DR: The analytical properties of N-nitroso-N-cyclohexylhexylhydroxylamine (hexahydrocupferron) are described in this paper.
TL;DR: In this paper, the hexahydrocupferrates of 17 metals (Cu, Pb, Bi, Sb, Al, Ti, Fe, Co, Ni, Mn, W, Mo, V, Ca. Sr, Ba and Mg) with chloroform was studied in relation to pH values.
TL;DR: In this paper, three binuclear complexes of Chromium(III) with ligand μ-oxalato are described: [(NH3]5Cr(C2O4) Cr(NH3)5]-S2O6)2·4H2O; [(NH 3]4H 2 O(H 2O(C 2O 4)Cr (H 2
TL;DR: In this article, the authors used data from five earthquakes in the Azores Islands recorded in nine stations on the European and American coasts to determine Rayleigh wave group velocity dispersion curves.
Abstract: Summary
Data from five earthquakes in the Azores Islands recorded in nine stations on the European and American coasts have been used to determine Rayleigh wave group velocity dispersion curves. Analysis of these observations leads to certain conclusions about the nature of the crustal and upper mantle structure in the North Atlantic Ocean. The main results are the presence of lower velocities in the upper mantle for the Atlantic than for the Pacific and the absence of appreciable influence of the Mid-Atlantic Ridge on the dispersion of surface waves.
TL;DR: In this article, the effects of the center-of-mass motion spuriosity on the BHF wave function were estimated using the harmonic oscillator representation of the wave function. But the effects were not considered in this paper.
K. G. M. M. Alberti, J. Iversen, N. J. Christensen, Anders F. Andersson1 +283 more•Institutions (37)
TL;DR: Cervical and endometrial biopsies revealed adenomatous cervical polyps and mesonephric adenocarcinoma of the endometrium of theendometrium.
TL;DR: In this paper, Liouville equation and projection operator techniques were used to obtain a compact equation for the rate of change of then-particle momentum distribution function to any order in the density.
Abstract: Starting from the Liouville equation and making use of projection operator techniques we obtain a compact equation for the rate of change of then-particle momentum distribution function to any order in the density. This equation is exact in the thermodynamic limit. The terms up to second order in the density are studied and expressions are given for the errors committed when one makes the usual hypothesis to derive generalized Boltzmann equations. Finally the Choh-Uhlenbeck operator is obtained under additional assumptions.
TL;DR: In this article, the Cabibbo transformation properties for the weak Hamiltonian were used to obtain a value of ≈ 0.6 for the S-wave isospin zero scattering length, in accordance with K e4 results but in violent disagreement with Weinberg's calculation.
TL;DR: The method the authors use to correct balanitic hypospadias is based upon the reconstruction of the urethra by means of rotating the skin flap taken from the penis.
TL;DR: In this paper, the existence of the Boltzmann equation and its generalizations is studied by analysing the order of magnitude of their terms, and it is shown that the reduced distribution functions are not analytic in the density.
Abstract: The existence of the Boltzmann equation and its generalizations is studied by analysing the order of magnitude of their terms. As a consequence we conclude that the reduced distribution functions are not analytic in the density.
TL;DR: In this article, the longitudinal and perpendicular polarizations of the energetic proton of the process ν μ + d → μ − + p + p using the impulse approximation were studied and the sensitivity of the polarization parameters to the second class axial current and to variations in the parameter M A of the axial form factor was considered.
TL;DR: It is concluded that it should be possible to find about 5% of abnormalities of tryptophan metabolism (kynurenine pathway) in the population of mentally subnormal children, some of them with a good biochemical and clinical response to different oral doses of vitamin B 6.
TL;DR: The significance of the gland openings with a white ring, in the colposcopic transformation zone, is reviewed and its importance discussed.
Abstract: Summary: The significance of the gland openings with a white ring, in the colposcopic transformation zone, is reviewed and its importance discussed.
This picture was present in 9.8% of colposcopic examinations on 914 patients selected on cytological and/or clinical basis. In these 90 patients cytology suggested mild dysplasia in 22.4% and severe dysplasia, carcinoma in situ or invasive carcinoma in 14.4%. Histological study in 73 of the 90 patients showed mild dysplasia in 20.5%, severe dysplasia in 13.7%, carcinoma in situ in 9.6% and invasive carcinoma in 1.3%.
We were impressed by the fact that these carcinomas showed very striking, easily identifiable glandular openings. We believe that the colposcopic study of the white gland openings is important, since they can be the only site where lesions are detected.
TL;DR: A plasma protein component with an apparent mol wt of 700,000 increases angiotensin II binding by macromolecules in arterial wall extracts, which increases its activity in several types of hypertension.