Showing papers by "University of Palermo published in 1968"
TL;DR: The data suggest that DNA 5-methylcytosine is synthesized at the polymer level in developing sea urchin embryos as it is known to occur in other organisms.
190 citations
TL;DR: In this article, from fresh bulbs of many varieties of daffodils, two compounds have been extracted, which show no basic properties since the nitrogen is amidic in character.
77 citations
TL;DR: In this article, two new diterpenes, sideridiol C 20 H 32 O 2 and siderol C 22 H 34 O 3, were extracted from the corols of Sideritis sicula Ucria (Fam. Labiatae).
47 citations
26 citations
24 citations
TL;DR: The presumptive muscle territory isolated at the 8-cell stage and then cultured for the period of normal embryonic development undergoes little if any differentiation, and although the cells derived from this territory seem able to synthesize specific muscle proteins, they are not able to organize them into myofibrils.
17 citations
TL;DR: In this article, the behavior of the beam-soil system is examined within the scope of the bilateral schematization of ideal elastoplastic bodies, in the following work stages; the expression for the limit load is supplied for each stage: the elastic unloading of the material, and the successive propagation of plastification in the soil which, being related to the displacement of the hinges in the beam, leads to the identification of the collapse mechanism of the systme.
Abstract: The behavior of the beam-soil system is examined within the scope of the bilateral schematization of ideal elastoplastic bodies, in the following work stages; the expression for the limit load is supplied for each stage:
Two peculiar features of the problem are highlighted:1) the “plastic hinge migration” phenomenon, due to the elastic unloading of the material, and2) the successive propagation of plastification in the soil which, being related to the displacement of the hinges in the beam, leads to the identification of the collapse mechanism of the systme.
14 citations
TL;DR: Micromeres of sea urchin (Paracentrotus lividus) have been isolated and cultured and electron microscopic observations show that the cells give rise to syncythia thus exhibiting a behaviour similar to that of the cells of the primary mesenchyme.
11 citations
TL;DR: In this paper, the experimental distribution of C2H5HgBr at 25°C between Amberlite CG-400 and aqueous LiBr(10−3−8 M) was determined.
8 citations
TL;DR: Gli AA. hanno somministrato in 5 soggetti normali normosomici, in 5 obesi metabolicamente sani and in 5 diabetici obesi un carico intragastrico (mediante sondino) di 9 aminoacidi essenziali as discussed by the authors.
Abstract: Gli AA. hanno somministrato in 5 soggetti normali normosomici, in 5 obesi metabolicamente sani e in 5 diabetici obesi un carico intragastrico (mediante sondino) di 9 aminoacidi essenziali (arginina, fenil-alanina, valina, leucina, lisina, metionina, isoleucina, istidina, triptofano) per un totale di g 30 ed hanno valutato la risposta insulo-pancreatica. In tutti i casi di soggetti in esame si e messo in evidenza un significativo aumento dell'insulinemia, determinata con metodo radioimmunologico. Il picco insulinemico e stato di 45 ± 11 µU/ml nei normali normosomici, di 65 ± 6 µU/ml negli obesi e di 52 ± 8 nei diabetici obesi, rispettivamente a 75 mp, a 60 mp e a 105 mp. La caduta insulinemica e stata piu lenta nei diabetici rispetto agli altri gruppi, per cui alla terza h si ritrovano in circolo concentrazioni di ormone elevate.
7 citations
TL;DR: Recombination between pairs of mutations in a cluster of seven cistrons controlling histidine biosynthesis is highly polarized, where the polarity is opposite at the opposite ends of the region.
Abstract: Recombination between pairs of mutations in a cluster of seven cistrons controlling histidine biosynthesis is highly polarized. The polarity is opposite at the opposite ends of the region. In experiments involving three his mutations it has been shown that recombination is the result of the transfer, from one parent to the other, of a segment going from the distal selected his+ allele to the end of the region. The rate of transfer is inversely proportional to the distance of the transferred his+ allele from the end of the region, at its side. A model of the process of recombination is discussed.
TL;DR: The broad implications of the study are that, in forecasting the outcomes of the presidential elections, public-image analysis is likely to be confounded by the phenomenon of selective perception as it is related to party affiliation.
Abstract: A technique is presented for evaluating the degree of support a candidate for national public office is likely to have at the polls. The technique involves the use of an adjective check list, Activity Vector Analysis (AVA), for which forms are available in French, Spanish, German, and Italian. Data are presented and discussed relative to a study made by the authors using this technique of public-image analysis just prior to the 1964 presidential elections in the United States. The data are based on the personality profiles of Johnson and Goldwater obtained from the public images held of these two candidates by 672 adults drawn from a population of voters representing a wide geographical distribution in the United States. From comparisons of the Ss' perceptions of Johnson and Goldwater and of the public image of each with an “ideal” President's profile established in an earlier study, no wide discrepancies were found between the public perceptions of the two major Presidential candidates in the 1964 electi...
TL;DR: In this paper, a semi-empirical method for the n-and π-electrons was developed, with the eigenfunctions expressed as an antisymmetrized product of two-electron functions or geminals.
Abstract: An attempt has been made to develop a semiempirical method which considers only the n- and π-electrons, with the eigenfunctions expressed as an antisymmetrized product of two-electron functions or geminals. These geminals are expressed as a linear combination of products of Huckel-type MO's and the matrix elements are evaluated assuming the strong orthogonality condition to hold among the geminals, with an average effective Hamiltonian where the interaction between paired electrons is explicitly included.
TL;DR: This article investigated the stability of educational elementary school pupils through the use of standardized achievement batteries in the professional literature and found that the batteries were effective in predicting the future educational progress of elementary school students.
Abstract: Judgments and predictions are frequently made about the future educational progress of students on the basis of performances on standardized achievement batteries administered in elementary school. However, few studies attempting to investigate the stability of educational elementary school pupils through the use of standardized achievement batteries are to be found in the professional literature. Such an opportunity has arisen in connection with a major project (Jackson & Cleveland, 1966) in which both of the authors have been involved.
TL;DR: It has been found that the specific activity of all the three enzymes undergoes an early increase followed by a fast return to normal or subnormal values, which is consistent with the sequential pattern of early enzyme changes which occur in the peripheral nerve of mammals during Wallenrian degeneration.
TL;DR: The perilymph is absorbed in the loose connective tissue of the modio-lum, the endolymph is absorption in the planum limbi and the interstitial liquid of the organ of Corti in the inner spiral sulcus.
Abstract: The perilymph is absorbed in the loose connective tissue of the modio-lum, the endolymph is absorbed in the planum limbi and the interstitial liquid of the organ of Corti in the inner spiral sulcus. The basin of the vein of the aqueduct of the cochlea in a fetal phase transfers almost only perilymph. When fully developed, many veins of the above-said basin are obliterated and the remaining ones transfer more blood than perilymph. From the interstitial spaces of the limbus the endolymph flows into the capillaries towards the inner auditory veins and the interstitial liquid of the organ of Corti flows towards the same veins by means of short lymphatic vessels.
TL;DR: Gli AA.
Abstract: Gli AA. hanno studiato il comportamento della risposta insulinemica dopo stimolazione con tolbutamide endovenosa in un piccolo gruppo di soggetti normali normosomici, obesi non diabetici e diabetici obesi. In tutti i soggetti il massimo aumento dell'insulinemia (determinata con metodo radio-immunologico) compare a 5 mp ed e maggiore negli obesi rispetto ai normali e ai diabetici. La caduta percentuale del picco insulinemico dimostra un andamento parallelo nei normali e negli obesi, mentre e molto piu lenta nei diabetici obesi. Vengono discusse le cause di questo comportamento e la natura dell'iperinsulinismo presente nell'obesita con e senza diminuita tolleranza agli idrati di carbonio.
TL;DR: In this article, an iterative procedure by which, starting from an approximate value of a root,z0=x0+jy0, of an algebraic equationF(z)=0, a sequence of values {zn} is obtained, aproximating the corresponding exact root; under certain conditions
Abstract: The paper shows an iterative procedure by which, starting from an approximate value of a root,z0=x0+jy0, of an algebraic equationF(z)=0, a sequence of values {zn} is obtained, aproximating the corresponding exact root; under certain conditions
TL;DR: In this paper, a metodo for the calcolo degli zeri complessi di a polinomio with caratteristiche intermedie is presented, e a retta di inclinazione variabile passante per l'origine del piano complesso is defined.
Abstract: Si espone un metodo per il calcolo degli zeri complessi di un polinomio che si presenta con caratteristiche intermedie tra quelli tradizionali del tipo «paper and pencil» e quelli sviluppati per l’impiego sui grandi calcolatori automatici. Il metodo e fondato su un principio analogo a quello di Aparo, ma utilizza una retta di inclinazione variabile passante per l’origine del piano complesso. Il passaggio di questa retta per gli zeri del polinomio viene individnato ricorrendo ad una opportuna variante del criterio di Routh, adattato allo studio della stabilita condizionata dei sistemi lineari.
TL;DR: Commercial Ultra-High-Speed Cameras for framing rates over 50,000 f.p.s. are very expensive and yield a small number of frames per run, but the single-flash technique with increasing delays gives photographs at a high framing rate over a comparatively long time and, as described here, requires no special electronic equipment except a good flash unit and a general-purpose oscilloscope.
Abstract: Commercial Ultra-High-Speed Cameras for framing rates over 50,000 f.p.s. are very expensive and yield a small number of frames (8 to 24) per run. The single-flash technique with increasing delays gives photographs at a high framing rate over a comparatively long time and, as described here, requires no special electronic equipment except a good flash unit and a general-purpose oscilloscope.
TL;DR: In this article, the uniqueness of the rational field and the Burnside theorem on the commutant of an irreducible set of operators of a finite dimensional vector space over an algebraically closed field were studied.
Abstract: Within a framework of general algebra we firstly formulate a proposition on the group of the automorphisms of some irreducible algebrae (id est algebrae without proper non trivial subalgebrae). This proposition includes as particular cases the uniqueness of the automorphisms of the rational field and the Burnside theorem on the commutant of an irreducible set of operators of a finite dimensional vector space over an algebraically closed field. Afterwards we apply the general proposition to modules with irreducible sets of semilinear operators and we obtain a theorem which generalises from several points of view the Burnside theorem. Finally we derive as an application a proposition which specifies the set of the Hermitian operators that commute with an irreducible set of semilinear operators of a finite dimensional real, complex or quaternion scalar product space.