Showing papers by "University of Bologna published in 1968"
TL;DR: It is reported that an apparently similar activation is brought about by treatment of rat liver supernatant with proteolytic enzymes.
135 citations
TL;DR: In this paper, it was shown that there is a size below which a coherent spherical precipitate cannot maintain a dislocation loop at its interface, and a size above which the incoherent (i.e. dislocated) state is stable with respect to the coherent state.
Abstract: It is shown that there is a size below which a coherent spherical precipitate cannot maintain a dislocation loop at its interface. There is also a size above which the incoherent (i.e. dislocated) state is stable with respect to the coherent state. Experiments in the electron microscope show that there is indeed a size above which a transition to incoherency can occur but that the observed critical size is bigger than that predicted theoretically. Reasons for this discrepancy are considered.
109 citations
100 citations
TL;DR: In this article, the type of source evolution implied by the radio data can be fitted by a simple model, which links with the X-ray background and the intergalactic cosmic ray density.
Abstract: Large radio sources are influenced by the intergalactic medium and the cosmic black body radiation, both of which depend on red-shift in a predictable way. The type of source evolution implied by the radio data can be fitted by a simple model. This topic links with the X-ray background and the intergalactic cosmic ray density.
68 citations
55 citations
TL;DR: This review is concerned with the functional significance of forebrain structures in sleep by presenting sleep phenomenology as a dynamic sequence of interrelated functional events that results from the integrative action of the whole nervous system.
45 citations
TL;DR: In this paper, the intensities of polarized Raman bands of carbon tetrachloride, benzene, cyclohexane, carbon disulfide, chloroform, acetone, and acetonitrile have been measured in binary mixtures with a wide variety of solvents, at concentrations ranging from 20 to 80% in volume.
44 citations
40 citations
TL;DR: GLC separations and mass spectrometric determinations were carried out on the trimethylsilyl derivatives of HFA, which show excellent GLC characteristics and favorable cleavages to determine the position of OH groups on the aliphatic chain.
Abstract: A method has been developed for GLC determination of hydroxy fatty acids (HFA) from cerebrosides of the central nervous system
39 citations
TL;DR: Polyribosomal patterns obtained by sucrose-density-gradient centrifugation showed highest radioactivity in the regions of 259s and 280s aggregates in those embryos in which thepolyamine contents were enhanced, whereas a decrease in the radioactivity was observed when the polyamine concentrations were decreased.
Abstract: 1. An increase in polyamine concentration, caused by inhibiting the amine oxidase activities with iproniazid, increased the incorporation of [3H]orotic acid into chick-embryo RNA and DNA. On the other hand, a decrease in polyamine concentration, obtained by causing an increase in amine oxidase activities, decreased [3H]orotic acid incorporation into nucleic acids. This was particularly evident for nuclear DNA and ribosomal RNA. 2. Polyribosomal patterns obtained by sucrose-density-gradient centrifugation showed highest radioactivity in the regions of 259s and 280s aggregates in those embryos in which the polyamine contents were enhanced, whereas a decrease in the radioactivity was observed when the polyamine concentrations were decreased. 3. The activity of DNA-dependent RNA polymerase, assayed in the same experimental conditions, also varied in the same fashion with changes in polyamine concentration.
39 citations
TL;DR: The present available data indicate that the amount of albumen solids begins to diminish starting from 11 to 12 days of incubation, and the protein content of the amniotic fluid shows a marked increase after the seroamniotic connexion perforates.
Abstract: In birds albumen represents a substantial part of the reserve material for their embryological development (Romanoff & Romanoff, 1949). In Gallus gallus albumen proteins form 50 % of non-incubated egg protein content (Romanoff & Romanoff, 1949). During incubation such material is absorbed and utilized, to a great extent, for the synthesis of embryonal proteins (Fiske & Boyden, 1926; Rupe & Farmer, 1955). It is not yet well understood how these processes (albumen absorption and utilization for the energetic and nutritional needs of the embryo) take place. The present available data indicate that the amount of albumen solids begins to diminish starting from 11 to 12 days of incubation (Romanoff & Romanoff, 1933; Rupe & Farmer, 1955). From 13 to 14 days, after the seroamniotic connexion perforates, the protein content of the amniotic fluid shows a marked increase because of the passage of albumen (Needham, 1931; Romanoff, 1960).
TL;DR: In this paper, an experimental apparatus is described and experimental results are presented on the drift velocity of electrons and holes in silicon in the 2·5 −12 kV/cm electric field range and at several temperatures between 300° and 77°K.
Abstract: In the present work an experimental apparatus is described and experimental results are presented on the drift velocity of electrons and holes in silicon in the 2·5–12 kV/cm electric field range and at several temperatures between 300° and 77°K Moreover, at temperatures near 77°K, an anisotropy effect is shown for electrons by means of samples cut in the (111) and (100) planes After discussing the method of measurement, the experimental data are compared with the published data
TL;DR: In this article, a comparative study of conflit cognitif interpersonel in Europe occidentale and USA is presented, showing that the differences cognitives ne sont reduites en Europe alors qu'elles le sont, lentement, aux Etats-Unis; and les sujets europeens aboutissent moins souvent que les SUJets americains a des solutions de compromis.
Abstract: Etude comparative du conflit cognitif interpersonel en Europe occidentale et aux Etats-Unis,—La recherche a ete menee conjointement dans divers pays europeens (Grande-Bretagne, France, Italic, RFA) et aux Etats-Unis, selon la měme procedure. On induit des differences cognitives detetminees entre les 2 membres d'un groupe, en les entra[icaron]nant differemment (ce dont ils ne sont pas conscients) dans une t[acaron]che d'apprentissage portant sur des problěmes politiques; il s'ensuit un conflit quand on reunit les deux sujets et qu'on leur demande d'aboutir a des solutions communes. Les resultats montrent que—a) les differences cognitives ne sont pas reduites en Europe alors qu'elles le sont, lentement, aux Etats-Unis;—b) les sujets europeens aboutissent moins souvent que les sujets americains a des solutions de compromis;—c) les europeens reagissent differemment a l'idee de ≪ Controle de l'Etat ≫. Ce type de recherche peut ětre utilise pour etudier le conflit cognitif sur une base interculturelle;...
TL;DR: In this paper, the undistorted motion of light pulses in a resonant medium is studied and conditions for self-induced transparency (2π-pulse) are given.
TL;DR: In this article, an ideal time variant system has been synthetized for the analysis of a sequence of random pulses and its performance has been evaluated under the hypothesis of gaussian noise and taking as criterion for the evaluation of amplitude resolution the rms deviation.
TL;DR: The peribronchial lymph nodes of 150 dogs from the province of Bologna were cultured for human pathogenic fungi and Hosplasma capsulatum was recovered from 2 dogs, indicating that an endemic area for H. Capsulatum exists in northern Italy.
Abstract: The peribronchial lymph nodes of 150 dogs from the province of Bologna were cultured for human pathogenic fungi. Hosplasma capsulatum was recovered from 2 dogs. This finding, coupled with an earlier isolation of H. capsulatum from a chicken yard soil sample from the same region, indicates that an endemic area for H. capsulatum exists in northern Italy.
TL;DR: A study on spermine and spermidine distribution and their ratio was carried out on seeds of 57 species belonging to different families of higher plants in particular to Papilionaceae, where a greater than one ratio was found in three genera: Phaseolus, Dolichos and Erythrina.
Abstract: Spermine and spermidine in seeds. A study on spermine and spermidine distribution and their ratio was carried out on seeds of 57 species belonging to different families of higher plants in particular to Papilionaceae. These two polyamines were found in all the species examined and the mayority have a lower than one ratio (spermine/spermidine). In the tribe of Phaseoleae (Papilionaceae), however a greater than one ratio was found in three genera: Phaseolus, Dolichos and Erythrina. This modified ratio was not found in the other two genera examined of this tribe (Vigna and Glycine) neither in the nearest tribe of Vicieae. This could be a confirmation of the close relationship existing between these three genera which has already been established on a morphologic basis.
TL;DR: In this paper, the diffraction of a plane wave incident on an isolated breakwater is studied, and the exact solution of the problem is briefly reported and a general method involving energies is used to determine comparative importance of the terms of the series which appear in the solution, which becomes of much greater facility in use in practical problems.
Abstract: The diffraction of a plane wave incident on an isolated breakwater is here studied: the exact solution of the problem is briefly reported and a general method involving energies is used to determine comparative importance of the terms of the series which appear in the solution, which becomes of much greater facility in use in practical problems. Numerical calculations have been carried out for twelve different cases, with the wavelength of the incident wave comparable to the length of the breakwater. Results are graphically shown in a set of tables.
TL;DR: In this paper, the analysis of neutral ϱπ system from π + d interactions at 5.1 GeV/c is presented, and evidence for a new isoscalar resonance (ϱπ) is reported.
TL;DR: In this paper, a very fast amplitude-to-digital converter was realized connecting a sampling height-totime converter to a digital time sorter with very good differential linearity and encoding accuracy.
TL;DR: In this paper, the authors measured the electron and hole drift velocity at electric fields ⩾ 3 kV/cm in a sample of high resistivity silicon enclosed in a container immersed in liquid helium and obtained a saturation drift velocity of 1.2 10 7 cm/sec.