showing 36 of ~574560 from 574555 documents
Ab initio study of rotational isomerism and electronic structure of isomeric bipyrroles
1985
Abstract Ab initio calculations using STO-3G and 4-31G basis sets have been performed on the internal rotation barriers and conformational stabilities for 2,3′- and 3,3′-bipyrrole. The twofold rotation potential predicted for both isomers at minimal basis level becomes a more involved fourfold potential when the split-valence basis set is employed, because it takes into account more properly the nonbonded interannular interactions. A transoid-gauche minimum is predicted to have the minimal absolute conformational energy in both isomers. The electronic structure of the highest occupied MOs of 2,2′-, 2,3′- and 3,3′-bipyrrole are analyzed in terms of the single pyrrole MO pattern and a similar…
L'historiographie ouvrière en Finlande
1985
PULMONARY AND CARDIAC COMPLICATIONS OF STAPHYLOCOCCAL OSTEOMYELITIS
1985
Pulmonary complications of staph.osteomyelitis seem to be infrequent and are seldom related in wide reviews of this entity and in texts of infectious diseases.Cardiac complications are still more infrequently found.However our experience is far from this observation. We have found pneumonic interstitial infiltrates and/or asymptomatic pneumatoceles in about two thirds of children suffering from staph. osteomyelitis to whom we have taken a weekly chest radiograph while they were feverish.Severe forms are rare.Lately,however,we have treated 5 children with acute staph.osteomyelitis,aged 6 to 13,and whith severe pulmonary and cardiac complications.They had broad bone lesions which affected (1)…
A low repeat length in oligodendrocyte chromatin
1985
Abstract: The behavior of oligodendrocyte chromatin after micrococcal nuclease digestion of nuclei was assayed in brains of rats of four different ages. During oligodendrocyte differentiation, a decreasing sensitivity of the chromatin to enzymatic attack was observed. On the other hand, the nucleosomal repeat length showed a slight tendency to increase during development. It is worth noting that even the highest values reported here for “oligodendrocyte’ chromatin repeat lengths are significantly lower than 200 base pairs, the value previously reported by others for “non‐astrocytic glia.” Copyright © 1985, Wiley Blackwell. All rights reserved
Interest, Voluntary Associations and the Stability of the Political System
1985
In this article the adequacy of the sociological paradigm in voluntary associ ations' research is investigated by comparing it with its nval, the incor poration or system integration paradigm (types 1 and 2) and with two approaches that are their combinations: multi-dimensional theones of disper sion and cross-cutting of interests (type 3) and multi-dimensional theories of incorporation and system integration of interests (type 4). I express the view that by themselves both pluralism and incorporation paradigms are , unable to depict the complex system of political stability. An adequate theory must contain elements of two dimensions of maintaining stability: firstly, the idea of dispersion…
Das Hypnoseverbrechen. Eine Betrachtung zur Frage der Widerstandsf�higkeit im Sinne des � 179 StGB
1985
Nach der Erorterung verschiedener Hypnosetheorien wird unter Berucksichtigung der physiologischen, psychologischen und behavioristisch-soziologischen Theorie anhand von 5 Fallen die Frage der Willensunfahigkeit im Sinne des § 179 StGB diskutiert und die Widerstandsunfahigkeit verneint.
Neutralization of Syllable-final Voicing in German
1985
German is well known for its neutralization of the voicing contrast in word-final obstruents. However, acoustic analysis of ten pairs of German words produced by ten native speakers revealed that the distributions of acoustic parameters for underlying voiced and voiceless stops are significantly different, despite considerable overlap between the two categories. Furthermore, in a listening test, German listeners were able to distinguish the voiced and voiceless pairs with about 60% accuracy—significantly better than chance. Several mechanisms for such a “semicontrast” are considered, including the possibility that it is an experimental artifact. It is concluded that this is not an artifact,…
Larva-to-adult and pupa-to-adult mortality dynamics in crowded cultures ofDrosophila melanogaster
1985
Pupal mortality is shown here to bear the main responsibility for total mortality duringDrosophila melanogaster development in crowded conditions. The dynamics of the pupa-to-adult and larva-to-adult processes of mortality follows a S-shaped logistic model, like survival in density-dependent processes. Data given here confirm to some extent Wallace's suggestion that pupal mortality is a density-dependent process.
A Method for Accurate Measurements of Optimum Noise Parameters of Microwave Transistors
1985
A method for measuring losses of the tuner network used as noise source admittance transformer in transistor noise parameter test-set is presented. Since the method is based on noise figure measurements, tuner losses can be determined on-line while performing measurements for determining transistor noise parameters. As experimental verifications the optimum noise parameters of a GaAs FET in the 4 - 12 GHz frequency range, measured through a computer-assisted measuring system, are reported.
PROMOTION OF INTRATHYMIC T-CELL DEVELOPMENT BY MHC-Ia-POSITIVE THYMIC MACROPHAGES (Ia + Mø)
1985
The generation of the peripheral T-cell pool is attributed to maturation and differentiation events occurring within the thymus. Three thymic compartments, thymic epithelial cells, thymic hormons and thymic Mo are considered to contribute to the intrathymic T-cell development. While, as we have shown earlier, murine as well as human MHC-Ia-negative-Mo (Ia−Mo) regulate thymocyte (TH) differentiation via suppressive effects (Thymus,6:295,1984) and MHC-Ia+-Mo are involved in intrathymic tolerance induction (Pediatr Res,15:800, 1984), now the contribution of Ia+Mo to intrathymic lymphopoiesis was investigated. An isolation method yielding cell suspensions highly enriched for Ia+ thymic Mo was p…
Analisis bayesiano de los contrastes de hipotesis parametricos
1985
Classical solutions to parametric hypothesis testing are shown to be particular instances of the Bayesian solution to a decision problem with two alternatives, in which the increase in utility for rejecting a false null is a linear function of the discrepancy between the accepted parametric model and the more likely model under the null.
Territorial localization of heat shock mRNA production in sea urchin gastrulae.
1985
In situ hybridization experiments with a labeled DNA probe indicate that the ability to respond to heat shock with the production of the mRNA for the 70 kd heat shock protein is segregated into the ectodermal cells already at the gastrula stage or earlier during the embryonic development of Paracentrotus lividus.
Vaccine production in China : assignment report : 4-22 mars 1985
1985
référence interne : 85055
Action collective et travail social
1985
Subsidization of higher education versus expansion of primary enrollments : what can a shift of resources achieve in Sub-Saharan Africa ?
1985
International audience; In many LDCs today, the distribution of public resources for education tends to be inefficient and inequitable in that subsidization often increases rather than decreases with the level of education. To improve efficiency and equity, a shift of resources from higher to primary education should therefore be considered. Such a shift would obviously imply an increase in the private cost of higher education, but its effect could be mitigated through a loan scheme. In this paper, our main purpose is to show what a cut in subsidies to higher education can achieve in terms of expanding primary enrollments. The results show that although the outcome differs from country to c…
Muon capture in a general class of weak models.
1985
We study muon capture by /sup 12/C in a general class of weak models. There is always a parameter characteristic of the weak model that can be extracted in a nuclear-model-independent way from the average polarization P/sub av/, the longitudinal polarization P/sub L//sup N/ and the asymmetry ..cap alpha.. in the angular distribution of recoils. For a less general class of models the asymmetry ..cap alpha.. is unnecessary. Using the experimental values of P/sub L//sup N/ and P/sub av/ we get a lower bound for the mass of the right-handed gauge boson of the left-right-symmetric model, M/sub W//sub R/> or =2.5ML, in a nuclear-model-independent way. The dependence of this bound on the experimen…
Patterns of Expression and Organization of Cytokeratin Intermediate Filaments
1985
Cytokeratins are a large multigene family comprising two polypeptide types, i.e. acidic (type I) and basic (type II) ones, which are distinguished on the basis of immunological, peptide mapping, mRNA hybridization, and primary amino acid sequence data. The acidic (type I) cytokeratins can be subdivided into at least two different subtypes on the basis of their carboxy-terminal sequences. Considerable interspecies conservation of sequences exists, even extending to the 3'-non-coding mRNA regions. Different pairs of type I and II cytokeratins show different resistance to dissociation in urea. Sequence differences of the type I cytokeratins containing functional domains may be an explanation o…
Study of a medium-size biological molecular association by means of a pair potential semiempirical approach: β-carboline-lumiflavin
1985
The molecular association between some substituted β-carbolines and a model flavin, lumiflavin, has been studied by means of a semiempirical approach proposed by Fraga based on a 1/R expansion of atom-atom pair potentials. Only stacked minima have been considered because of their possible biological interest. The calculations characterize 15 different minimum stacked conformations, most of them occurring in the complexes considered. The structural and energetic effects of 1–Me, 6–OH and 7–OH substituents of β-carboline are discussed. An equilibrium conformation involving geometric overlap between the pteridinic portion of flavin and the indole group of β-carboline is predicted to be the mos…
N-Acetylneuraminic acid storage disease
1985
Increased amounts of free sialic acid were found in body fluids, leukocytes, cultured fibroblasts, and liver tissue of a four-year-old boy with mental retardation, ataxia, and clinical and radiologic findings of a mild mucopolysaccharidosis. A diagnosis of Salla disease was made though in contrast to earlier reports, recurrent upper respiratory infections and hepatosplenomegaly were present already in infancy, and skeletal abnormalities of dysostosis multiplex were found in early childhood. Free sialic acid in the urine was identified as N-acetylneuraminic acid by 1H-NMR spectroscopy. Sialidase activities were normal. Increased amounts of bound sialic acid were found in liver and cultured f…
L'aide extérieure à l'éducation en Afrique sub-saharienne
1985
International audience; Sur la base d'une exploitation originale des rapports annuels sur l'assistance extérieure qu'établissent les représentants résidents du PNUD dans les pays d'Afrique sub-saharienne, cet article analyse la structure de l'aide que reçoivent ces pays pour l'éducation. Cette aide n'est pratiquement pas déterminée par des facteurs éducatifs, et sa répartition entre les niveaux d'enseignement s'avère cautionner de mauvais choix.
Ent-clerodane diterpenoids from six further species of Teucrium
1985
Abstract Fifteen further species of the genus Teucrium have been investigated. Six of them contain known ent -clerodane diterpenoids; the others did not yield any diterpenoid. The chemotaxonomic significance of these results is discussed.
Subharmonic phase-lock criteria for a class of weakly non-linear high-order oscillators
1985
Subharmonic frequency entrainment of high-order weakly non-linear oscillators is investigated. For the class of circuits considered, equations are first derived which provide the first approximation values for the amplitudes and phases of the two main spectral components of the steady-state waveform. Necessary and sufficient stability criteria are then derived in explicit from. The example worked out (a negative conductance double-tuned oscillator) shows the efficiency and ease of use of the proposed method.
The comparative spreading behavior of enantiomeric and racemic tyrosine amphiphiles
1985
Several derivatives of tyrosine or its methyl ester have been synthesized in which the para hydroxyl group on the aromatic side chain has been converted to a long chain alkyl ether or urethane. The surface behavior of these compounds is discussed. Enantiomeric discrimination, the ability of a chiral molecule to distinguish between mirror-image stereoisomers, has been investigated for the urethane derivates by comparing the surface pressure-area isotherms of the enantiomer with that of the racemic compound. Enantiomeric discrimination was demonstrated for the methyl ester analog, but was not conclusively observed for the zwitterionic compounds. Possible structural requirements for enantiomer…
Changes of energy metabolism, myosin light chain composition, lactate dehydrogenase isozyme pattern and fibre type distribution of denervated fast-tw…
1985
The influence of low frequency (8-10 Hz) electrical stimulation on denervated fast-twitch muscle from rabbit was investigated. Prolonged direct stimulation of denervated muscle resulted in higher oxidative enzyme activities. Furthermore, single fibre analyses for succinate dehydrogenase showed a more uniform distribution of activity in stimulated-denervated muscle when compared to normal muscle. As was also the case following stimulation of innervated muscle, glycolytic enzymes were decreased in activity and the LDH-isozyme pattern was also shifted towards heart type. No change of the myosin light chain pattern could be observed after 56 days of stimulation.
Tumor dedifferentiation: an important step in tumor invasion.
1985
Tumor invasion in vivo was studied by light and electron microscopy as well as by immunofluorescence microscopy. Special regard was paid to the grade of tumor differentiation. Dimethylhydrazine-induced murine colonic carcinomas comprising a differentiated and an undifferentiated tumor type with low and high invasiveness respectively, were used. At the invasion front of both tumor types a striking dissociation of the organized tumor cell complexes into isolated tumor cells was found together with a loss of most of the cytological features of differentiation. It is supposed that this process mobilizes the tumor cells from the main tumor bulk enabling them to invade the host tissue by active l…
Preliminary studies on reproduction of Puntazzo puntazzo (Gmelin 1789) (Pisces, Sparidae) under controlled conditions
1985
Abstract Experiments were carried out under controlled conditions in September 1983 on the reproduction of Puntazzo puntazzo (sheepshead bream). The techniques adopted to stimulate spawning, the egg characteristics, and the phases of embryonal development until the sixth day after hatching are described. The best spawning results were obtained with intramuscular injections of HCG at 1 I.U./g of body weight. Optimal fertilization and hatching were observed at 22°C, the mean temperature of the sea water during the natural period of reproduction of Puntazzo puntazzo .
L'enseignement agricole entre l'attraction de l'urbain et le retour à la ferme : une vue transversale
1985
International audience
L'influence des évènements familiaux dans la formation des revenus
1985
Référence interne : 85013; En décomposant l'expérience professionnelle des hommes et des femmes en fonction d'évènements familiaux marquants, l'objectif est de mesurer l'effet du mariage sur les gains, et de mettre en relation le bénéfice de l'union avec le niveau d'éducation de l'individu. L'approche suivie analyse également le role de la fécondité, en particularisant l'effet de l'espacement des naissances et de l'âge à la première naissance sur les profils de salaires.
Die 2-(Triphenylphosphonio)isopropyloxycarbonyl-(Ppoc-)-Gruppe und am Phosphoniumzentrum modizifierte analoge Reste als Aminoschutzgruppen bei der Pe…
1985
Die Einfuhrung in Aminosauren, die Stabilitat bei Peptidsynthesen und die selektive Abspaltung der 2-(Triphenylphosphonio)isopropyloxycarbonyl-(Ppoc-)-Aminoschutzgruppe sowie ihrer Varianten mit (Methyl)(diphenyl)phosphonium- und (Dimethyl)(phenyl)phosphoniumkopfen werden beschrieben. Der Ppoc-Rest ist in etwa um den Faktor 4 basenstabiler als der entsprechende 2-(Triphenylphosphonio)ethoxycarbonyl-(Peoc-)Rest. Er kann dennoch bereits bei pH = 8 in wasrig-methanolischer Hydrogencarbonatlosung von der blockierten Aminofunktion abgelost werden. Im Gegensatz zur Peoc-Abspaltung treten dabei keine storenden Nebenreaktionen des entstehenden Propenylphosphoniumsalzes mit der freigesetzten Aminofu…
La formulation de l'evaporation sous forme d'une loi d'Ohm
1985
National audience
Mise a jour des definitions sur l'evapotranspiration et les besoins en eau des cultures
1985
National audience
ChemInform Abstract: SYNTHESIS OF THE GLYCOPEPTIDE PARTIAL SEQUENCE A80-A84 OF HUMAN FIBROBLAST INTERFERON
1985
The glycopentapeptide H-(GlcNAcβ1-)Asn-Glu-Thr-Ile-Val-OH (10) representing the partial sequence A80–A84 of human fibroblast interferon was synthesized using the newly developed allyl-ester protection of carboxy functions. The allyl esters, which are stable to acids and to bases, can be cleaved under very mild, neutral conditions using tris(triphenylphosphine)rhodium(I) chloride or tetrakis(triphenylphosphine)palladium(0) as a catalyst. This synthetic method opens up a preparative route to glycopeptide model structures of glycoproteins of high biological interest.
On the symbol homomorphism of a certain Frechet algebra of singular integral operators
1985
We prove the surjectivity of the symbol map of the Frechet algebra obtained by completing an algebra of convolution and multiplication operators in the topology generated by all L2-Sobolev norms. The proof is based on an ℝn of Egorov's theorem valid for non-homogeneous principal symbols, discussed in [5], [6]. We use the hyperbolic equation ∂u/∂t=i|D|ηu, 0<η<1, which has its characteristic flow constant at infinity, so that no differentiability of the symbol is required there.
Complexes of tetra(parasulphonatephenyl)porphyrinato ferrate(III), FeTPPs, with 1,10 phenanthroline and 2,2′ bipyridine ligands
1985
Abstract Iron(III) porphyrin, FeTPPS, gives high-spin 1:1 monomeric complexes with the ligands 1,10 phenanthroline, 2,9 dimethylphenanthroline and 2,2 bipyridine in aqueous solution. Absorption spectrum of the complexes is very different to the one of the monomer metalloporphyrin, but nearly identical to the visible spectrum of the μ-oxo dimer Fe2(TPPS)2O. A spectrophotometric study of the formation equilibria yields the following values of the stability constants: Me2phen 4.3 × 104, phen 1.1 × 104, bipy 2.0 × 102 (25 °C, 0.1 M NaNO3). Analysis of the experimental data strongly suggest that the ligands are hydrogen bonded to one coordinated water molecule (TPPS)FeOH2 → (LL). Although the …
Clinicopathological conference: an adolescent girl with severe mental impairment and mucopolysacchariduria.
1985
Effect of EDTA and citrate on the functional activity of the first component of complement, C1, and the C1q subcomponent.
1985
The first component of complement, C1, is a calcium-dependent complex of the three distinct subcomponents, C1q, C1r, and C1s. Earlier observations revealed that treatment of C1 with EDTA led to a loss of hemolytic C1 activity even after recalcification. Therefore, it was of interest to study whether EDTA has an additional effect on C1 and its subcomponents, beside its chelating capacity. The chelating effect of EDTA was compared to that of citrate. It was found that treatment of C1 or C1 with EDTA followed by addition of Ca++ led to a loss of hemolytic activity up to 90%, depending on EDTA concentration. Even pretreatment of EDTA with varying amounts of Ca++ did not prevent the inactivation…