Théorie du capital humain et analyse des scolarisations : une application au cas du système éducatif français

1980

International audience; L’article cherche à expliquer la très grande variance qu’on observe en matière de scolarisation individuelle. Après avoir proposé des estimations des rendements de l’investissement éducatif aux différents niveaux et conclu à l’insuffisance de la théorie du capital humain sous sa forme initiale pour rendre compte des faits, une tentative est menée pour interpréter les décisions éducatives en essayant de séparer les effets cognitifs des effets sociaux. Des estimations opérées à partir de l’enquête longitudinale de l’INED indiquent que les effets cognitifs ont une part relativement faible (25 %) dans l'explication, alors que les conditions économiques familiales semblen…

Rapid continous radiochemical separations by thermochromatography in connection with a gas-jet recoil-transport system

1980

Abstract A combination of a gas-jet recoil-transport system with a thermochromatographic system has been studied as a technique for rapid, continuous radiochemical separations. Fission products were used as a model for complex mixtures of elements. A nitrogen gas-jet containing potassium chloride clusters was applied to transport nuclides produced in a reactor from the target area to the thermochromatographic column. Conversion of the reaction products carried by the gas-jet volatile species was achieved by stopping the clusters in a quartz-wool plug located in the column and kept at high temperatures and feeding a reactive gas into the column. Several reactive gases producing volatile chlo…

Untersuchungen zur thermodynamik und konformation von makromolekülen in polymermischungen in der nähe von entmischungspunkten durch neutronenbeugung

1980

Chlorophyll-Protein Complexes of Chlorella fusca

1980

Chlorophyll-protein complexes from thylakoids of the normal type and two mutants of Chlorella fusca were separated using sodium dodecyl sulfate acrylamide gel electrophoresis (PAGE). The properties of the chlorophyll-protein complexes of the three strains of Chlorella were compared. Standard curves were set up for the characterization of the chlorophyll-proteins. In every electrophoretic separation of chlorophyll-protein complexes, a certain amount of pigment is separated from the protein. We tried to keep that amount as low as possible by mild solubiliza­tion and by working in low temperature. Under these conditions, we obtained several new chlorophyll-proteins in addition to the P-700-chl…

The on-line isotope separation facility helios at the mainz reactor

1980

Abstract The on-line isotope separation facility HELIOS consisting of a helium-jet transport system coupled to a high transmission mass separator is described. The main characteristics of the system were determined from γ-ray measurements on neutron-rich nuclides. The transmission from the target to the skimmer is about 60%; the overall efficiency for typical fission product elements is 0.05–0.2% and the transit time for Cs is about 1.0 s.

A computer program suitable for analysis of choice of categories in biomedical data recognition problems.

1980

The optimum choice of categories in problems of medical data recognition is governed by the choice of categories, the selection of appropriate features, and by the choice of a loss function. Under these circumstances it is often difficult to find out the suitable classification scheme. The computer program described here serves for the design of the optimum recognition procedure. The Bayes rule is used as decision rule. A criterion for the comparison of different choice of categories is given. The program can be performed after estimation of the underlying prior probabilities and the conditional densities obtained from a training set, and before testing the decision rule with real data.

Determination of nuclear spins of short-lived isotopes by laser induced fluorescence

1980

Abstract The spins of several nuclear ground and isomeric states have been measured for a number of mercury isotopes. The fluorescent light from the 6s6p3P1 state is observed at 2537 A after excitation with the frequency doubled output of a pulse dye laser. Four different laser induced fluorescence techniques were tested for their applicability: double resonance, Hanle effect, time delayed integral Hanle beats, and time resolved quantum beats. The sensitivity and selectivity of these models are compared with emphasis on the determination of spins of nuclei far from beta-stability, where short half lives and low production yields restrict the number of available atoms. The experiments were c…

T-T cell interactions during in vitro cytotoxic T lymphocyte responses. III. Antigen-specific T helper cells release nonspecific mediator(s) able to …

1980

T helper cell induction and the specificity of T cell-mediated help as generated during alloreactive and H-2-restricted, virus- or hapten-specific cytotoxic T lymphocyte (CTL) responses have been compared. With the use of a double-chamber culture system, it was possible to dissect and separately analyze the induction phase of T helper cells from the T helper cell effector function. The data obtained revealed that during alloreactive as well as H-2-restricted T cell responses, antigen-specific T helper cells are induced. Upon specific restimulation of T helper cells, helper cell function is mediated across a cell-impermeable membrane via soluble products in an apparently nonspecific and nonr…

Activity of bulbar respiratory modulated neurons and restart of respiration after hypocapnic apnea in rabbits

1980

The activity of respiratory modulated neurons at the end of the apneic pause and during restart of respiration and the diaphragmatic mass activity were examined and both were compared to quiet respiration. Thresholds of mutual inhibition of neurons are unevenly distributed within various phase types of neurons.

Testing of a model for the non linear electric behavior of polymeric materials

1980

Some experimental results relative to a molten polymer (a commercial polyisobutylene) in d.c. and a.c. tests are presented.

Regional hypothermia of the kidney: surface or transarterial perfusion cooling? A functional study.

1980

Hypothermia reduces ischemic damage if prolonged occlusion of the renal artery is required during an in situ kidney operation. Hypothermia may be achieved by external cooling or by transarterial hypothermic perfusion. External cooling may lower intrarenal temperature heterogeneously. Perfusion techniques via intra-arterial catheters introduced percutaneously are associated with minimal technical difficulties. The 95 patients who underwent extensive hypothermic nephrolithotomy had differential 131iodine hippuran clearance studies preoperatively, and 2 weeks and 6 to 46 months postoperatively. Sixty-three kidneys were cooled by transarterial hypothermic perfusion and 39 were cooled with topic…

ARE AMORPHOUS ALLOYS SUITABLE AS A STORAGE MATRIX FOR FISSION PRODUCT KRYPTON ?

1980

Rheological characterization of polycaprolactam anionically synthesized in the presence of lithium chloride

1980

Melt viscosity and dynamic-mechanical data are reported for samples obtained by anionic polymerization of caprolactam, in the presence of LiCl. The full body of results is essentially in line with those previously reported relative to mixtures of inorganic salts and commercial nylon 6, In particular a drastic-decrease of the melting point and of the rate of crystallization is confirmed as well as an increase of the glass transition temperature and of the melt viscosity. Some quantitative differences exist, which may be attributed to the different molecular weight distribution in the polymers employed in the present work.

T cell-mediated cytotoxic immune responsiveness of chimeric mice bearing a thymus graft fully allogeneic to the graft of lymphoid stem cells

1980

Fully allogeneic, chimeric mice were established by adult thymectomy of (A × B) F1animals, grafting parental A-type thymus under the kidney capsula, followed by lethal (900 rd) irradiation and reconstitution with B parental-type bone marrow cells treated with xenogeneic anti-T cell antiserum plus complement. Following in vivo sensitization with inactivated Sendai virus (SV) suspensions, no virus-specific T cells could be detected within the spleen cells of the mice. Upon stimulation with third-party allogeneic cells in a primary mixed lymphocyte culture, spleen cells of all animals generated alloreactive cytotoxic T lymphocytes (CTL). More interestingly, upon secondary in vitro stimulation …

Cefotaxim bei Infektionen während einer Granulozytopenie im Rahmen von malignen Hämoblastosen und Knochenmarksinsuffizienz

1980

Die antibiotische Therapie mit Cefotaxim bei Patienten, die aufgrund einer Granulozytopenie im Rahmen einer malignen Hamoblastose oder einer Knochenmarksinsuffizienz eine verminderte Infektabwehr aufweisen, zeigte einen guten therapeutischen Effekt. Eine Heilung der Infektion konnte bei acht von siebzehn Patienten erzielt werden, eine Besserung bei drei Patienten; bei zwei Patienten trat ein Rezidiv auf, ein Patient sprach bei totaler Agranulozytose weder auf Cefotaxim noch auf andere Antibiotika an. Bei einem Patienten muste die Therapie wegen eines Exanthems abgebrochen werden. Zwei Patienten verstarben wahrend der Therapie an ihrem Grundleiden.

Characteristics of haloethylene-induced acetonemia in rats.

1980

A series of halogenated ethylenes (vinyl chloride, vinylidene fluoride,cis- andtrans-1,2-dichloroethylene, perchloroethylene) induces increased acetone exhalation in rats. Exposures of differently pre-treated rats to vinylidene fluoride suggest that a metabolite of the haloethylene must be envolved in eliciting this formation of acetone. This conclusion is based on (a) dependence of acetone exhalation on the concentration of vinylidene fluoride, (b) effect of inducing agents, (c) effect of pyrazol, a metabolic inhibitor, (d) effect of cysteine, (e) effect of hypoxia and (f) the time course of acetone exhalation.

Neutral deoxyribonucleases of HeLa S3 cells: electrophoretic separation, characterization, substrate specificity and mode of action.

1980

Extracts of HeLa S3 cells were electrophoresed on polyacrylamide gels; gel slices were eluted and the eluates were assayed for DNase activities against native and denatured DNA substrates in the presence of MgCl2 or Na2EDTA. Aliquots of each eluate were also assayed for their ability to nick the circular supercoiled PM2 phage DNA to distinguish endonucleases from exonucleases. Peaks of endonuclease activities were characterized as forming 3′-phospho-oligonucleotides or 5′-phospho-oligonucleotides by the use of oligonucleotides produced by these enzymes as substrates for the 5′-phosphate-specific snake venom exonuclease. The total activity of DNases in gel eluates was much higher than that i…

Elevation of hepatic epoxide hydratase activity by ethoxyquin is due to increased synthesis of the enzyme.

1980

Abstract Feeding of the antioxidant ethoxyquin to rats leads to an increase of epoxide hydratase activity in liver microsomes. The apparent half life of the increase is 3–4 days. Elevation of epoxide hydratase activity is also obtained by intraperitoneal treatment of mice with ethoxyquin. This elevation is prevented by concomitant treatment with cycloheximide. When radiolabelled leucine is incorporated into microsomal protein by liver cell fractions from either ethoxyquin-fed or untreated rats, gel electrophoresis reveals that ethoxyquin feeding increases incorporation into epoxide hydratase. These results suggest that the elevation of epoxide hydratase activity by ethoxyquin is due to incr…

Breaststroke swimmer's knee

1980

The cause of the breaststroke swimmer's knee with medial pain of the knee joint has not been clearly identified. Breaststroke swimmers with knee pain were, therefore, examined arthros copically. None showed any other disorders of their knees than medial synovitis in seven of nine swimmers. Since structural abnormalities could be ruled out, biomechanical analyses utiliz ing cinematographic techniques were used to study patients swimming in a special flume with the speed set at 90% of their best competitive performance. The results indicate that the extension and flexion and also in some cases the hip abduction and adduction movements of the whip kick were performed with high peak angular ve…

Studies on the Intravesical Action of Topically Administered G 3 H-Doxorubicin Hydrochloride in Men: Plasma Uptake and Tumor Penetration

1980

AbstractDoxorubicin hydrochloride has been used for the treatment and prevention of recurrences of transitional cell carcinoma. Ideal indications for the drug and side effects have not been determined. In this regard the penetration of the drug into the bladder wall and the urothelium as a urinary blood barrier is of interest. Using a tritium label we have investigated tumor penetration and transmucosal plasma uptake of doxorubicin hydrochloride after intravesical application in 7 patients with stage A bladder tumors. Of the 7 patients 5 were free of tumor following transurethral resection and 2 had recurrent disease. The patients free of tumor received 40mg. doxorubicin hydrochloride per 3…

Inhibition of GABA and benzodiazepine receptor binding by penicillins.

1980

Penicillins are thought to be GABA receptor antagonists. In order to determine the affinities of various penicillin derivatives for the GABA receptor, their potencies as inhibitors of specific [3H]GABA binding to rat brain membranes were investigated. All investigated penicillins inhibit specific [3H]GABA binding, with IC50 values ranging from 2 to 60 mM. The results are consistent with the assumption that penicillins are weak GABA receptor antagonists.

Glomerul�re Amyloidose des Menschen ? unter besonderer Ber�cksichtigung der Proteinurie und der Amyloidogenese

1980

Light and electron microscopic investigations were carried out on kidney biopsies in renal amyloidosis cases. Particular attention was paid to the relationships between glomerular amyloidosis and proteinuria.

Mononuclear heterocyclic rearrangements 5. Kinetic Investigation of the behaviour of (e)- and (z)-phenylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadia…

1980

The kinetic behaviour of the geometrical isomers I-E and I-Z of the title compound in the presence of piperidine in benzene has been investigated. The kinetic results suggest that I-Z rearranges directly into 2,5-diphenyl-4-benzoylamino-1,2,3-triazole (II), whereas I-E probably rearranges only through the intermediate I-Z formed by isomerization. All the reactions studied are piperidine-catalyzed.

Zinn—Chalkogen-heterocyclen

1980

Abstract The preparation of a new six-membered ring compound (CH 3 ) 8 Sn 4 Te 2 containing two SnSn bonds isolated by Te is described and its structure established by means of analytical vibrational and NMR spectroscopic data. The well crystallizing yellow compound undergoes light-induced disproportionation reactions showing the generation of dimethylstannylene, which can be trapped either by CH 3 I or by the parent compound itself. In the latter case the reaction leads to five-membered rings with Sn 3 Te 2 - and Sn 4 Te-skeletons, respectively.

Benzodiazepine receptor interactions may be involved in the neurotoxicity of various penicillin derivatives

1980

The interaction of seven penicillin derivatives with specific [3H]flunitrazepam binding to benzodiazepine receptors was investigated. The affinities of the penicillins for benzodiazepine receptor seemed to depend on the lipophilia of the derivatives. The concentrations of the penicillins which inhibit specific [3H]flunitrazepam binding are consistent with penicillin levels found in the central nervous system of patients developing penicillin induced convulsions. The results suggest that penicillins inhibit GABAergic transmission not only at the GABA receptor, but also at the benzodiazepine receptor, which is thought to be part of a neuronal system facilitating GABAergic transmission. Both m…

Hepatitis B virus in diabetic patients

1980

The presence of HBV markers was determined in 149 serum samples obtained from diabetic patients and was compared with a normal population. Diabetics have the same incidence of HBsAg but significantly higher anti-HBc antibodies. These differences were seen in the group of diabetics on oral hypoglycemic therapy. These results cannot yet be explained.

Hydrierende enthalogenierung von oligo[(hydroxyphenylen)-methylen]-verbindungen

1980

Über antimon-haltige heterocyclen

1980

Abstract p -Nitrophenyl- and p -tolyl-oxadithia- and trithiastibocanes have been synthesized from the respective aryldichlorostibane and dithiole. The compounds have been characterised by means of 13 C NMR and vibrational spectra (ν(SBS 2 ) 350–320 cm −1 ). The crystal structure of p -nitrophenyltrithiastibocane has been determined ( R = 0.042). The eight-membered ring exhibits a boat-chair conformation. Single-bond distances of SbC and SbS (219, 244 and 245 pm), a 1,5-transannular Sb⋯S interaction (319 pm), and Sb⋯S and Sb⋯O (339 and 353 pm) intermolecular contacts, result in a six-coordinated Sb III (ψ-monocapped octahedral) species. The two additional Sb⋯S distances are in accordance w…

Klinische Erfahrungen mit Cefotaxim in der inneren Medizin

1980

Es wurden 36 Patienten mit Cefotaxim behandelt, wovon wahrend der Therapie ein Patient im Leberausfallkoma verstarb, zwei Patienten verstarben an den Folgen einer Herzinsuffizienz mit Lungenembolie. Ein Patient erhielt Cefotaxim prophylaktisch vor Herzkatheteruntersuchung bei Verdacht auf Endokarditis. Sechzehn Patienten wurden von ihrer Infektion geheilt, sieben Patienten gebessert, bei drei Patienten war eine Besserung mit Rezidiv zu beobachten, wahrend bei sechs Patienten keine Heilung eintrat. Alle Patienten hatten nach klinischen Kriterien schwere bis lebensbedrohliche bakterielle Infektionen, deren Heilung durch ernste Grunderkrankungen prognostisch ungunstig erschien. Die bei einem P…

Use of electron microscopy to obtain quantitative information about the melting behavior of branched polyethylene

1980

The melting behavior of low-density polyethylene was studied by electron microscopy. The experimental techniques and method of evaluation chosen were such as to deliver quantitative numerical data. The values which could be derived from suitably prepared histograms were the minimum, maximum, average, and most probable values of the crystal thickness d and long-spacing L. All these values were in good agreement with small-angle x-ray scattering results. The histograms also show the distribution functions for d and L, so that effects leading to changes in the average values can be observed in detail. The results provide further support for a model of melting and crystallization proposed in a …

Über polygermane

1980

Abstract A complete series of 5-membered heterocycles (Ph 2 Ge) 4 X with X = O, S, Se and Te has been prepared and investigated by mass spectra, 13 C NMR spectra and vibrational spectra. The 13 C signals of the phenyl groups in the compounds (Ph 2 Ge) 4 X were compared with the related values in the homocycle (Ph 2 Ge) 5 . Frequency values for the symmetrical and asymmetrical stretching vibrations of the units GeGeGe and GeXGe are given. The crystal structure of the compound (Ph 2 Ge) 4 S has been determined and refined to a R of 0.051. The 5-membered ring Ge 4 S exhibits envelope conformation.

false

1980

A phenomenological theory of the Phase Distribution Chromatography (PDC)-separation effect is outlined and a theoretical equation for the measured PDC-calibration curves is given. Assuming a reversible-thermodynamical equilibrium in the polystyrene-PDC-column, only a relatively small part of the measured PDC-calibration curves could be explained: namely those running below their tangents. In order to explain the whole sigmoidal shape of the experimental curves, a theory of steady state in the system sol/gel was developed assuming deformation of the polymer coil near the gel front due to the stress related to the velocity gradient. The resulting dynamical flow-equilibrium differs highly from…

Energy-Linked Reactions Catalyzed by the Purified ATPase Complex (F0F1) from Rhodospirillum rubrum Chromatophores

1980

1. The isolation of the F0F1-ATPase complex from Rhodospirillum rubrum chromatophores by the use of taurodeoxycholate is described. 2. The enzyme preparation contains about 12 polypeptides; five are subunits of the F1 moiety. 3. The ATPase activity of the purified enzyme is dependent on the addition of phospholipids. 4. Km-vales for Mg2+-ATP and Ca2+-ATP are similar to the values obtained for the membrane-bound enzyme. 5. The F0F1-ATPase complex is more than 70% inhibited by oligomycin and N,N′-dicyclohexyl-carbodiimide. 6. The F0F1-ATPase complex was integrated into liposomes. The reconstituted proteoliposomes catalyzed energy transduction as shown by ATP-dependent quenching of acridine dy…

Eine präparative monohydroxymethylierung höhermolekularer, molekulareinheitlicher oligo[(5-alkyl-2-hydroxy-1,3-phenylen)methylen]e mit formaldehyd

1980

Double-blind cross-over study with oral alpha-ketoacids in patients with chronic renal failure.

1980

In 15 ambulatory patients with renal insufficiency (creatinine clearance, 9.9 +/- 3.0 ml/min) the effect of oral supplementation with alpha-ketoacids has been compared with that of placebo. The protein intake amounted to 0.55 g protein per kilogram body weight of high biological value, as estimated by dietary recordings. After a control period of 3 months the patients received, in a double-blind study, 1.05 g alpha-ketoacids/10 kg body weight per day or a placebo for 6 weeks with a subsequent cross-over. Fasting blood samples were analyzed at 3-week intervals for routine laboratory parameters and 17 proteins. Anthropometric and clinical data have been recorded every 3 weeks. While therapy w…

Time course of excitatory and inhibitory states of bulbar respiratory modulated neurons.

1980

In respiratory modulated neurons of rabbits, vagally mediated inhibition is not bound to resting membrane potential oscillations. Latency of spinally evoked antidromical spike invasion, however, is shorter and threshold voltage is lower during the shift of membrane potential towards depolarization accompanying burst discharge.