Showing papers by "University of Perugia published in 1975"
TL;DR: In this article, a general discussion of the Cs+ or Rb+-ion exchange behavior on zirconium phosphate at various degree of crystallinity is made, and it is concluded that the low, apparent selectivity of crystalline zircanium phosphate towards large monovalent ions is due to steric hindrance and therefore enlarged phases of this exchanger, such as Zr(HPO4)2.8H2O (10·4 A), are expected to have a high selectivity towards Cs+, or even larger cations.
81 citations
TL;DR: In this paper, it was shown that algebraic geometry is equal to geometric logic on the basis of the fact that both are the studies of continuous maps between coherent topoi, and that logic should be regarded as including the formalism of closed categories whereas the form of the linear algebra calculations in geometry is that of (abelian and) closed categories.
Abstract: Publisher Summary The (elementary) theory of topoi is the basis for the study of continuously variable structures as classical set theory is the basis for the study of constant structures. Sheaves on a coherent topological space also occur in algebraic geometry. This chapter illustrates that algebraic geometry is equal to geometric logic. Each can be transformed into the other on the basis of the fact that both are the studies of continuous maps between coherent topoi. This claim metaphysically ignores the dominating aspect in algebraic geometry of calculations in linear algebra. Logic should be regarded as including the formalism of closed categories, whereas the form of the linear algebra calculations in geometry is that of (abelian and) closed categories.
71 citations
TL;DR: The rate of synthesis of phosphatidylcholine, choline plasmalogen and sphingomyelin (and their hydrosoluble precursors) in isolated neuronal and glial cells has been investigated and the injected radioactivity incorporated only into the base moiety of the choline lipids in both cell types.
Abstract: —
[Methyl-3H]choline has been injected intraventricularly into adult rabbits, and the rate of synthesis of phosphatidylcholine, choline plasmalogen and sphingomyelin (and their hydrosoluble precursors) in isolated neuronal and glial cells has been investigated. At all time intervals examined, the injected radioactivity was incorporated only into the base moiety of the choline lipids in both cell types. Maximum labelling of the two choline phosphoglycerides occurred in neurons 150 min after administration, whereas the highest specific radioactivity for glial phosphatidylcholine and choline plasmalogen was reached at 6 and 10 h, respectively. At any time interval examined, the neuronal and glial choline plasmalogen displayed a higher specific radioactivity than the corresponding diacyl-derivative. The two phosphoglycerides incorporated the base in both cell populations at a faster rate than did whole brain tissue. Sphingomyelin was labelled in both cells at a low rate and acquired measurable radioactivity levels only after 2 h from isotope administration.
Highest levels of radioactivity for phosphorylcholine and cytidine-5′-diphosphocholine were reached in both neurons and glia 1-2 h after administration, but these levels per unit protein were higher in glial than in neuronal cells.
36 citations
TL;DR: The analyses on separated primitive and definitive erythrocytes show that the first contain four hemoglobins different from the adult ones, while the second contains two hemoglOBins identical to the adult Ones but their ratios change gradually during development and approach that of the adult hemogloblins at hatching.
26 citations
TL;DR: Various kinetic properties of the 1-alkyl-2-acyl-sn-glycerophosphorylethanolamine synthesizing phosphotransferase activity were found to be similar both in neurons and glia.
Abstract: The transfer of radioactivity from cytidine-5′-diphosphate ethanolamine into 1-alkyl-2-acyl-sn-glycerophosphorylethanolamine of neuronal and glial cells from adult rabbit brain cortex has been investigated in vitro. The synthesis of 1-alkyl-2-acyl-sn-glycerophosphorylethanolamine in both cell populations was stimulated 23–25-fold by the addition of 6 mM alkylacylglycerol. The neuronal cell-enriched fraction was found to possess/unit protein a 1.7–1.8-fold ethanolaminephosphotransferase activity (EC 2.7.8.1), as compared to the glial fraction, when saturating concentrations (6 mM) of alkylacylglycerols were added in the incubation system. The neuronal/glial ratio was 2.6–2.8 in the absence of lipid acceptor or with low concentrations of alkylacylglycerol. Under most favorable conditions, 6.4 and 3.3. nmoles 1-alkyl-2-acyl-sn-glycerophosphorylethanol-amine/mg protein/30 min was obtained for neurons and glia, respectively. Various kinetic properties of the 1-alkyl-2-acyl-sn-glycerophosphorylethanolamine synthesizing phosphotransferase activity were found to be similar both in neurons and glia.
25 citations
TL;DR: It is shown that different degrees of displacement of the lipid-bound labelled ethanolamine are obtained by the exchange in vitro dependent on the mechanism of prelabelling the PE-containing rnicrosomes, pointing to the existence in brain of at least two biochemically different pools of microsomal PE.
23 citations
19 citations
19 citations
TL;DR: The results showed that the amount of PAH in the fuels tested, increases with an increase in the concentration of C9-C10+ aromatics, but it was not possible to ascertain whether it was the PAH content of the Fuels or the C9−C10 and higher aromatic hydrocarbons content which was the more important factor as discussed by the authors.
18 citations
18 citations
TL;DR: The interaction of LDOPA decarboxylase from hog kidney with its substrates is studied by means of spectrophotometry, and it is able to provide evidence for at least three enzymesubstrate or enzyme-product complexes; a quite unusual absorbance spectrum has been observed for two of them.
TL;DR: In this article, Nitrogen position and internal heavy atom effects on the radiative and radiationless transitions from the lowest excited states of the isomeric azaphenanthrenes and some of their methyl, chlorine and bromine derivatives have been studied in EPA solutions at 77 K.
TL;DR: The reaction between π-(PhCHCHCOR)Fe(CO) 3 (R = H, CH 3, Ph) and L (L = PPh 3, AsPh 3, SbPh 3 ) in acetone occurs in two steps as discussed by the authors.
01 Sep 1975
TL;DR: Roscherite from Lavra da Ilha, Taquaral, Minas Gerais is a magnesian roscherite as discussed by the authors, which is a one-dimensional nonterminated structure of tetrahedra.
Abstract: Roscherite from Lavra da Ilha, Taquaral, Minas Gerais is a magnesian roscherite. Semiquantitative chemical analyses and crystal-structure investigation indicate its chemical formula to be
$$(Al_{{\raise0.7ex\hbox{$2$} \!\mathord{\left/ {\vphantom {2 3}}\right.\kern-
ulldelimiterspace}\!\lower0.7ex\hbox{$3$}}} \square _{{\raise0.7ex\hbox{$1$} \!\mathord{\left/ {\vphantom {1 3}}\right.\kern-
ulldelimiterspace}\!\lower0.7ex\hbox{$3$}}} )Ca(Mg_{0.7} Fe_{0.3}^{2 + } )_2 Be_2 (PO_4 )_3 (OH)_3 \cdot 2H_2 O.$$
The lattice parameters arc:a=15.874A,b=11.854 A,c=6.605 A, β=95.34°; space groupC 2/c,Z=4. The finalR value is 0.073 for the 2129 observed reflections collected on a four-circle diffractometer, with graphite monochromated MoKα radiation, up to 2 π=70°. The crystal structure is partially disordered around the site at the origin with aluminum ions in highly distorted octahedral coordination, and with Al−O bond values spread over a large range. Coordination around Ca, Mg, Be and P cations is regular. According to the classification for tetrahedral motifs proposed byZoltai, roscherite belongs to the one-dimensionally non-terminated structures of tetrahedra. Rings of four tetrahedra [two PO4 and two BeO3(OH) groups] alternate with single PO4 tetrahedra to form chains parallel to [101].
TL;DR: Atypical forms of retinal pigment dystrophy occurring during the course of ocular myopathy appear to be clinical expressions of a unique genetic defect confined to the pigment epithelial layer.
TL;DR: In this paper, the electric dipole moments of two series of molecules (CH 3 ) 3 MX with M C, Si, Ge, Sn and Pb, and X ǫ Cl and Br have been determined, and it is suggested that the extent of back-bonding decreases with an increase in the atomic number of M.
TL;DR: In this paper, the effect of solvent acidity on the reciprocal interconversion of ground state species in water glassy solutions was investigated and it was shown that their reciprocal inter-conversion depends on the environmental conditions.
TL;DR: The ultrastructure of the myoneural junctions in the body wall muscles has been studied in Branchiobdella pentodonta Whit and a single junctional type has been found.
Abstract: The ultrastructure of the myoneural junctions in the body wall muscles has been studied in Branchiobdella pentodonta Whit. A single junctional type has been found. Within the terminal axon there are two types of vesicles, which differ in number, size and electron opacity. The junctional gap contains the basement membrane. The post-junctional membrane displays concave patches on which slender projections arising from the outer lamina of the sarcolemma extend into the junctional gap. These concave patches overlie a cytoplasmic lamina made up of electron dense material.
TL;DR: The clinical features and cytogenetic Giemsa banding studies of a case of partial trisomy 4p showed an aberration resulted from a reciprocal translocation rcq(4p 21p; 4q 21q) found in the mother.
Abstract: The clinical features and cytogenetic Giemsa banding studies of a case of partial trisomy 4p [47,XX,+der(21), der(4), der(21), t(4p 21p;4q 21q) mat] are presented. This aberration resulted from a reciprocal translocation rcq(4p 21p; 4q 21q) found in the mother.
TL;DR: In this paper, the electric dipole moments of the complexes π-LFe(CO)3, where L = trans-PhCHCHCHO, trans-phCH-CHCOMe, transPhCH-COPE, transphPH-CHCOPh, trans, transPHCH-CA, CH-CA and CH2-CHCHO were measured and a vectorial analysis of the moments leads to the conclusion that the complexes are π in type.
TL;DR: The place of evaluation in the several phases of training programs is presented as an on-going educational process and the sources and methodes of data collection on the improvement in trainee performance are specified.
Abstract: The place of evaluation in the several phases of training programs is presented as an on-going educational process. The framework specifies the sources and methodes of data collection on: (1) the improvement in trainee performance, (2) the relevance of the program to the community; (3) the involvement of appropriate groups in planning; (4) the planning process itself; (5) the utilization and diffusion of evaluative feedback; and (6) the consequences of the training activity for the sponsoring organization and consumer.
TL;DR: The combination of oxprenolol with dihydralazine and hydrochlorothiazide caused larger reductions in blood pressure, particularly with oxp Renolol 80 mg, which was well tolerated; major side effects occurred in three patients.
Abstract: In a multicentre, double-blind, between-patient study the hypotensive effect of oxprenolol was investigated in 329 patients with mild to moderate hypertension. A factorial experimental design with three factors was chosen: oxprenolol--none or daily doses of 20, 40, 60 and 80 mg; dihydralazine and hydrochlorothiazide, respectively, none or 30 mg daily. Each treatment was given for 4 weeks after an adequate period of withdrawal from any other possible hypotensive therapy and one week of placebo wash-out. Irresponsive of the association with dihydralazine and/or hydrochlorothiazide, oxprenolol had a hypotensive effect linearly related to dose for standing systolic (P less than 0.05) and diastolic (P less than 0.01) pressure, and for lying diastolic (P less than 0.05) pressure. The additional of dihydralazine enhanced the time-course of the hypotensive effect of oxprenolol, particularly the 80 mg dose level. In general, the combination of oxprenolol with dihydralazine and hydrochlorothiazide caused larger reductions in blood pressure, particularly with oxprenolol 80 mg. In the latter group, the eventual falls in blood pressure were 30.5 and 14.4 mmHg for lying systolic and diastolic, respectively; and 32.1 and 20.0 mmHg for the standing systolic and diastolic pressures. The drug was well tolerated; major side effects (heart failure and bronchospasm) occurred in three patients.
TL;DR: A case of acute lymphatic leukemia in a 7-month-pregnant Italian Friesian cow, aged about 6 years and belonging to a small dairy herd of 11 cows is described, where C-type particles were found in milk samples from 3 cows with persistent lymphocytosis.
Abstract: A case of acute lymphatic leukemia in a 7-month-pregnant Italian Friesian cow, aged about 6 years and belonging to a small dairy herd of 11 cows is described. Hematologic, histopatologic and ultras...
TL;DR: L'attività della 5′-nucleotidasi secreta dalle vescichette seminali sia, al pari di altre presenti in vari organi dei mammiferi, modulata da cationi bivalenti.
Abstract: La 5′-nucleotidasi del plasma seminale bovino e inibita competitivamente da nucleosidi di- e trifosfato. L'inibizione osservata in presenza di ADP o ATP e rimossa da ioni magnesio a concentrazioni fisiologiche. Questo risultato suggerisce che l'attivita della 5′-nucleotidasi secreta dalle vescichette seminali sia, al pari di altre presenti in vari organi dei mammiferi, modulata da cationi bivalenti.
TL;DR: The data suggest that DIC-treated tumor sublines and H -2-incompatible allogeneic lymphoma cells are subjected to comparable rejection processes in the peritoneal cavity of mice.
TL;DR: Three strains of bovid herpesvirus 2, viz.
TL;DR: In this article, the 13C NMR spectra of fusicoccin and its derivatives were studied using standard Fourier transform techniques, T1 relaxation time measurements and lanthanide shift reagents, the resonances of individual carbon-13 nuclei were assigned.
Abstract: The 13C NMR spectra of fusicoccin, some of its cometabolites and derivatives were studied. Using standard Fourier transform techniques, T1 relaxation time measurements and lanthanide shift reagents, the resonances of individual carbon-13 nuclei were assigned.
TL;DR: The ligand behaviour of polymethylenebis(phenylthiourea), L, compounds: PhNH·C-S·NH·CH2·CH(Me)·CS·NHPh (I); PhNH ·CS ·NH·(CH2)n·NH-CS·NPh (n = 2-10) (II)-(X) and triethylaminetris ((phenylTHiouera), N(C2H4NH·CS-NHPh)3 (XI), towards CoX2 (X�