showing 36 of ~574560 from 574555 documents
An ab initio CI study on the rotational barrier of the allyl anion
1986
All-electron and pseudopotential non-empirical calculations have been performed on C 2v and C s (syn, anti) allyl anion conformations. Using a double-zeta valence-shell basis set within the Epstein-Nesbet definition of the unperturbed Hamiltonian, a value about 19 kcal/mol is found for the barrier to rotation of the allyl anion. This value is the theoretical value obtained with greater accuracy, and the lowest one for the rotational barrier.
Electrofunctional features of the tilted disc syndrome.
1986
The ERG, EOG and VEPs of 15 patients with tilted disc syndrome were studied. The ERG showed abnormal amplitudes in about 1/4 of the eyes and the EOG values were pathological in 3 patients. It is probable that the abnormality of the inferior-nasal portion of the retina and retinal pigment epithelium seen in the tilted disc syndrome causes the changes in the ERG and EOG. Pattern VEPs latency was delayed in most patients. This finding is probably due to the poor focusing of the light in the retina.
Bias the estimates of the returns ot education in the Mincerian earnings functions as a result of cohort effects
1986
Sedimentation of dissolved macromolecules in the vicinity of the consolute point 1. Strictly binary systems and kinetic considerations
1986
This paper analyzes the effect of gravity on polymer solutions near the consolute point. Calculations are carried out for monodisperse polystyrene in cyclohexane using the Flory-Huggins expression with a concentration-dependent interaction parameter for the free energy of mixing. Depending on molecular weight and distance to the demixing temperature, the influence of gravity leads to non-negligible gradients of the volume fraction in the one-phase region as well as in the two-phase region. In particular, the effect of gravity on the measurement of the coexistence curve in a finite sample is calculated explicitly.
Inhibition of adenosine trephosphatase activity from a plasma membrane fraction of acer pseudoplatanus cells by 2,2,2-trichloroethyl 3,4-dichlorocarb…
1986
2,2,2-Trichloroethyl 3,4-dichlorocarbanilate (SW26) is toxic for Acer pseudoplatanus cell cultures. It inhibited the cellular proton extrusion and depolarized the plasmalemma. In vitro, it inhibited the plasma membrane ATPase. SW 26 was also inhibitory to membrane ATPases of other origins-plant (maize shoot), fungus (Schizosaccharomyces pombe), and animal (dog kidney)-with about the same efficiency (7.5 micromolar < I(50) < 22 micromolar). It did not inhibit the oligomycin-sensitive ATPase from purified plant mitochondria, nor molybdate-sensitive soluble phosphatases. SW26 was more specific for plasma membrane ATPases than diethylstilbestrol or vanadate. A Lineweaver-Burk plot analysis show…
Decay properties of very-high-spin states in transitional Er nuclei aroundA=154
1986
Theγ ray continuum structures of the transitional Er isotopes withA∼154 are studied using the reaction74Ge(84Kr,xn)158−xEr atElab=340 MeV. The measurements include energy spectra, total energies, multiplicities, angular distributions and lifetimes using the DSAM method. The analysis of data confirms the previously observed two-bump structure of the continuum radiation. A meticulous subtraction of discrete contributions proves the persistence of the low-energy bump even at high spins, i.e.I>40ħ. The angular-distribution measurements assign predominant dipole structure to the bump atEγ=0.65 MeV, whereas the bump atEγ=1.3 MeV is of almost pure quadrupole character at high spins. The lifetime m…
Influence of a continuous quenching procedure on the initial stages of spinodal decomposition
1986
Instead of the standard assumption in the theory of phase separation where an instantaneous quench from an initial equilibrium state to the final state in the two-phase region is assumed, we consider the more realistic situation that the change of the external control parameter (e.g. temperature) can only be performed with finite rates. During the initial stages of spinodal decomposition the system then has some “memory” of the states intermediate between the initial and the final one. This influence of the finite quench rate in continuous quenching procedures is studied within the linearized theory of spinodal decomposition, with the Langer-Baron-Miller decoupling, and with Monte Carlo sim…
Les dépenses d'éducation des familles en République de Guinée
1986
Radiative capture of protons by the deformed nuclide232Th
1986
The excitation function for the radiative capture232Th(p, γ)233Pa has been determined in the proton energy range 7 to 20 MeV by an activation method. The results are compared with a compound nucleus model prediction and earlier experimental data for another deformed nuclide176Yb. As in previous cases an enhancement over the CN-model prediction is observed and the excitation of the giant dipole resonance via the direct-semidirect reaction process is a likely explanation. Supplementary measurements of the232Th (p, f) excitation function in the proton energy range 11–20 MeV have been performed.
Interaction of diazepam with surfactants. Spectrophotometric and spectrofluorometric study
1986
Abstract The interaction of diazepam with non-ionic, anionic and cationic surfactants has been studied spectrophotometrically and fluorometrically. It has been verified that the absorption spectrum of diazepam is not modified in micellar medium. However, a dramatic five-fold increase in fluorescence sensitivity is observed in the presence of sodium lauryl sulphate (SDS). The experimental conditions, temperature, pH and surfactant concentration have been optimized to improve the fluorometric determination of diazepam and a detection limit of 0,04 ppmhas been obtained.
Aortic dissection detected by transoesophageal echocardiography
1986
The diagnostic value of transoesophageal echocardiography was evaluated in 24 patients with aortic dissection and compared to transthoracic two-dimensional echocardiography, computer tomography, aortography, surgery and autopsy. Using transoesophageal echocardiography we found in 5 patients a type I dissection, in 5 patients a type II and in 14 patients a type III dissection. Transthoracic two-dimensional echocardiography was positive in 3/5 type I, 2/5 in type II and 2/14 in type III dissections. Computer tomography was unable to demonstrate an intimal flap in 1/2 patients with type I, 2/3 type II and 1/11 type III dissections. Aortography was negative in 1/4 type I, 3/5 type II and 3/12 p…
Solid state polymerization of new polyesters containing diacetylenic groups
1986
Synthesis and properties of some new polyesters of 10, 12-docosadiyn-1, 22-diol are described. The diyn-polyesters as films became coloured polydiacetylenic films on exposure to UV radiation and their properties were studied.
Is the acidity of ascitic fluid a reliable index in making the presumptive diagnosis of spontaneous bacterial peritonitis?
1986
Ascitic fluid pH and arterial-ascitic fluid pH gradient were compared to ascitic fluid polymorphonuclear cell count in 84 patients with cirrhotic ascites and in 12 with malignant ascites to assess their role as diagnostic tests for spontaneous bacterial peritonitis and to clarify the relationship between ascitic fluid pH and lactate. Ascitic fluid pH was significantly lower (pH 7.30) in spontaneous bacterial peritonitis (n = 18) and probable spontaneous bacterial peritonitis (n = 12) than in sterileascites (pH 7.41; n = 54). Since blood pH levels were not different in the presence of infection, arterial-ascitic fluid pH gradient was significantly higher in spontaneous bacterial peritonitis …
?-constraint with respect to a Fitting class
1986
Estimations de la rentabilité des études dans les fonctions de gains : problèmes de spécification, effets de génération
1986
Quantitative Prediction of Concentration Effects in Steric Exclusion Chromatography
1986
Abstract A semiempirical model, based on a previous one quantitatively describing the dependence of the elution volume, V(cA), on the concentration of injected polymer, cA, in exclusion chromatography (SEC) at dilute solutions, has been developed. In the derived equation, concentration effects are mainly governed by the Huggins' coefficient, kA, and by the quadratic coefficient in the polynomial expansion of the reduced specific viscosity, kA. Because of the incertitudes on reliable kA and kA' values, these are respectively removed from the model through she Imai's equation and the empirical correlation kA' + 0.122=kA, here obtained. Thus, A predicted elution volumes besides polymer concent…
Social Class and Changes in Health-Related Habits in Finland in 1973–1983
1986
The aim of this project was to study social class differences with respect to various health-related habits and especially to note the changes in these habits after a 10-year follow-up period. From this study conclusions can be drawn as to whether health education efforts and increased interest in personal health has been more widely adopted by the more educated groups than the less educated groups, whose morbidity and mortality rates are higher. The sample consisted of 902 white-collar and blue-collar workers. Smoking was found to be more common among blue-collar workers in both years. Smoking rates had declined in all groups except female blue-collar workers. Occasions of drinking were m…
Italian registry of patients off therapy after childhood acute lymphoblastic leukemia. Results after first phase of data collection
1986
The Italian Registry of Off-Therapy patients after childhood tumors now includes 760 subjects with acute lymphoblastic leukemia. These patients were all removed from treatment by December 31, 1981, and were followed in 35 different institutions. All the children have received multiple-drug treatment, combined, in 79.7% of the cases, with cranial irradiation. Thirty-nine (5%) experienced a relapse before treatment suspension. Total duration of antileukemic therapy ranges between 18 and 131 months (median, 38). At the last updating (December 31, 1981), 699 subjects were alive, 6 were lost to follow-up, and 55 had died. Life-table analysis shows that 90.8% were alive and 77% were alive in cont…
El sistema de transportes en España y Francia, 1750–1850. A proposito de dos libros recientes
1986
Tradicionalmente, la literatura sobre historia económica del transporte ha partido de la irrupción del ferrocarril como medio revolucionario en la economía decimonónica. Así, la atención preferente de los investigadores ha recaído sobre los procesos de construcción de la red ferroviaria en los diversos países y en el impacto para la economía del nuevo sistema de comunicaciones. Sin embargo, son menos numerosos los trabajos sobre los distintos modos de transporte en períodos anteriores al advenimiento de la época ferroviaria, y muchos menos los que han tenido en cuenta en sus análisis las vías de comunicación, su estado y organización en el espacio, en relación con las posibilidades de desar…
On-line measurements of body fat content by the caliper method
1986
Nuclear ground-state properties in a relativistic Meson-Field theory
1986
We investigate the ability of a relativistic Mean-Field theory to reproduce nuclear ground state properties by an exhaustive fit to experimental data. We find that the bulk properties of nuclei from16O to208Pb can be adjusted very well. There remain problems with level density and fluctuations in the charge density similar as in fits using the conventional Skyrme Hartree-Fock model.
Assessment of successful valve reconstruction by intraoperative transesophageal echocardiography (TEE)
1986
In 17 patients (10 patients with mitral insufficiency, 5 patients with tricuspid regurgitation, 2 patients with mitral stenosis) the result of valve reconstruction was evaluated by intraoperative two-dimensional transesophageal contrast-echocardiography (TEE). Therefore, 1–2 cc of an agitated contrast-medium (GelifundolR) were injected into the left or right ventricle. The result of reconstruction was assessed by the extent of regurgitant microbubbles into the left or right atrium. A successful valve repair could be demonstrated in 15 patients without or with only minimal regurgitation of contrast-fluid. In one patient residual severe mitral insufficiency after valve reconstruction could on…
Zur Einstellung Jugendlicher gegenüber ihrer kieferorthopädischen Behandlung
1986
In den Jahren 1980/81 wurden 2991 vorwiegend 16jahrige Schuler verschiedener Schultypen, einschlieslich der Berufsschule, mit einem Fragebogen befragt und im Anschlus daran klinisch untersucht. Die Jugendlichen, bei denen eine kieferorthopadische Behandlung durchgefuhrt worden war oder die noch in kieferorthopadischer Behandlung standen, hatten zudem zpezielle Fragen zu dieser Behandlung zu beantworten. In dieser Arbeit werden vorwiegend Fragen zur kieferorthopadischen Behandlung diskutiert: Wer gab den Anstos zu der kieferorthopadischen Behandlung? Wie lange dauerte sie, welche Anspruche bezuglich Tragezeiten wurden an den Patienten gestellt und wie wurden diese von ihm erfullt? Die Ursach…
Au Musée de la Résistance et de la Déportation de Besançon. Enquête par questionnaire
1986
International audience
Pentafulvene durch Aminomethinylierung des Cyclopentadiens
1986
Aus der Dreikomponentenreaktion von Cyclopentadien (1) mit s-Triazin (2) und einem sekundaren Amin 4 gehen die cyclisch N,N-disubstituierten Pentafulven-6-amine 5 und die cyclisch N1,N1-disubstituierten N2-(6-Pentafulvenyl)formamidine 7 hervor. Unter den biologischen Eigenschaften der neuen Verbindungen ist besonders die anthelminthische Wirkung von 5d interessant. Pentafulvenes by Aminomethynylation of Cyclopentadiene The three component reaction comprising the interaction of cyclopentadiene (1) with s-triazine (2) and a secondary amine 4 leads to the cyclic N,N-disubstituted pentafulven-6-amines 5 and the cyclic N1,N1-disubstituted N2-(6-pentafulvenyl)formamidines 7. Among the biological …
Role of the functional group in n-octydimethylsilanes in the synthesis of C8 reversed-phase silica packings for high-performance liquid chromatography
1986
Abstract C8 reversed-phase packings have been sysnthesised by reaction of a 25-nm pore-size high-performance liquid chromatographic silica (10 μm, as(BET) = 297 m2 g-1) with 2,4-lutidine as base and dichloromethane and N,N-dimethylflormamide as solvents, or without solvents and with the following silanes: n-octyldimenthylchlorosilane (C8-Cl), n-octyldimethylhydroxysilane (C8-OH), n-octyldimethylmethoxysilane (C8-OCH3), n-octyldimethylethoxysilane (C8-OC2H5), n-octyldimethyl(dimethylamino) silane [C8-N(CH3)2], n-octyldimethyl(trifluoroacetoxy)silane (C8- OCOCF3), and bis-(n-octyldimethylsiloxane) (C8-O-C8). C8-Cl, C8-OH and C8-OCH3 each form a reactive intermediate with 2,4-lutidine, favouri…
Stomach signet-ring cancer cell line (MZ-STO-1), established in tissue culture: Morphological characterization and antigenic profile
1986
Anomalous pressure dependence of the Lamb-Mössbauer factor in a spin crossover system
1986
The dependence of the f-factor on temperature and on pressure up to 1500 bar has been measured in the spin crossover compound [Fe(2-pic-ND2)3]cl2·EtOD. In the transition region around Tc=146.7 K the pressure dependence of f shows an anomalous increase, which can be explained on the basis of a theoretical model for spin transitions developed by us.
Bourgogne : l'entrée des filles dans la vie active
1986
A Novel Histogram for Partial Discharge Signals in HV Insulating Systems
1986
A technique for relating measurable electrical quantities with energies dissipated inside a void in highly electrically stressed insulation is presented. It is based on measuring, for each apparent discharge level qe, the algebraic sum of the external energy pulses of all discharges having a value qe and occurring over some cycles of test voltage. Theoretical investigations show that the results of such external energy summations are equal to the energies dissipated in the void. A novel histogram is also suggested which relates the apparent discharge amplitudes with their respective energies in the void. Experimental tests were carried out under controlled conditions with samples of thermop…
The social phenomenon of education as the foundation of generational differences
1986
Partint de la concepcio de l'individu com a esser eminentment social, es passa a analitzar d'una banda a) la influencia que el medi social exerceix sobre el fenomen educatiu, estant aquesta influencia mediatitzada fonamentalment per la personalitat de l'individu, en la constitucio participen elements hereditaris o congenits i influxos ambientals, i per un altre, b) la influencia que l'educacio com a tal exerceix en el medi, podent ella propiciar un canvi social, en el si del qual apareixeria el conflicte generacional les arrels fonamentals del qual son: el xoc ontologic, el psicologic i el social.
Frenkel-Kontorova model with anharmonic interactions
1986
It is shown that consideration of more realistic interatomic potentials (with limited tensile strength) within the framework of the Frenkel-Kontorova model may lead to a breakdown of the soliton picture in systems with competing periodicities. Closed analytical expressions for the form of a single soliton in an anharmonic chain reveal discontinuities which indicate a disintegration of the entire system beyond some critical values of the misfit, and/or of the height of the periodic substrate potential. The length of anharmonic solitons depends essentially on both the sign and the magnitude of the misfit. The influence of misfit on the pinning-unpinning transition is also investigated.
Blood flow, oxygen consumption and substrate utilization of human tumors xenotransplanted into nude rats
1986
Comportement des entreprises et pratiques de l'administration en matière d'emploi obligatoire des travailleurs handicapés : le cas de la Côte d'Or
1986
Time-dependent monomerization of gramicidin A, enhanced by phosphatidylcholine in non-polar solvents
1986
Abstract The usefulness of size-exclusion high-performance liquid chromatography for the study of gramicidin A dimer—monomer conformational equilibrium in non
false
1986
The kinetics of polyamidation was investigated for the reaction of diphenyl terephthalate as activated diester with trimethylhexamethylenediamine (1 : 1 mixture of 2,2,4- and 2,4,4-trimethyl isomers) in dimethyl sulfoxide. The good solubility of the resulting polyamide (Trogamid®(poly(iminoterephthaloylimino-x,y,z-trimethylhexamethylene))) assured a reaction in which all reactants, especially the polyamide, were soluble. The conversion was followed by analysis of the phenol set free and by measuring the number-average degree of polymerization Pn of the polyamide. The reaction obeyed an overall second order with the principle of equal reactivity of functional groups fulfilled for Pn ≿ 16. De…