Isotopic Effects and Surface Absorption in $^{35-37}$Cl+$^{24}$Mg Interactions

1992

Abstract The few-nucleon transfer is found to play an important role in the isotopic effects observed in absorption. This conclusion is obtained by measuring elastic scattering and quasielastic reactions and by analysing elastic data with both phenomenological and microscopic models. The sensitivity domain is found to be different for imaginary and real potentials. The implication for the validity of the dispersion relation for phenomenological potentials at the real sensitivity radius, when transfers are important, is discussed.

Metal ion complexation by tetraester derivatives of bridged calix [4] arenes

1992

A series of bridged calix [4] arenes (5–10 methylene groups in the bridge) were synthesized and transformed into their tetraester derivatives by reaction with ethyl bromoacetate. The stability constants for complexes of the tetraester derivatives with sodium, potassium and silver cations, determined in methanol by spectroscopic or potentiometric techniques, show a drastic decrease (more than 105 for Na +) for the shorter methylene chains. 1H NMR studies demonstrate a conformational rearrangement of the calixarene part to fourfold symmetry to be necessary for the complexation of a cation, which is prevented by the shorter chains. This is further confirmed by the X-ray structure of a tetraest…

Modulation of IL-2, IFN-γ, TNF-α and IL-4 production in mice of different ages by thymopentin

1992

The effect of an immunomodulator drug thymopentin (TP5) on the production of various cytokines (IFN-gamma, IL-2, IL-4, TNF-alpha) in mice of different ages has been studied. TP5 enhanced IL-2, TNF-alpha and IFN-gamma production but reduced the IL-4 secretion by splenocytes from aged mice (greater than 120 week old) in vitro. However, it had no effect on the IL-2, IFN-gamma, TNF-alpha or IL-4 production by splenocytes from young and adult mice. TP5 injected subcutaneously was able to induce high levels of IL-2 production by splenocytes from all groups of mice. The TP5 effect on TNF-alpha and IFN-gamma was similar, even though it was significant only in old mice. Furthermore, TP5 was able to …

On the canonical structure of higher-derivative field theories. The gravitational WZW-model

1992

Abstract A general expression for the symplectic structure of a higher-derivative lagrangian field theory is given. General relativity and the gravitational WZW-model are considered in this framework. In the second case we work out explicitly the Poisson bracket for both chiral solutions giving rise, in two different ways, to the classical exchange algebra of the SL q (2) group.

Nucleon structure functions from deep inelastic muon scattering

1992

Abstract Recent experimental results from the CERN NA37 (NMC) experiment on deep inelastic muon scattering on hydrogen and deuterium are presented. Absolute structure functions have been measured at 90 and 280 GeV incident energy covering the kinematical range 0.006 2 2 . The new results help to resolve the severe discrepancies between the data of the previous experiments. In addition data on the structure function ratio F 2 n /F 2 p are reviewed. Evidence for a non-leading twist at × ⪆ 0.20 is extracted from the Q 2 dependence of the structure function ratio. Its effect on the determination of the Gottfried sum rule is discussed.

Chemical Constituents of Urospermum picroides

1992

Seven phenolic compounds were isolated from the aerial parts of U. picroides. They were identified by UV spectra, TLC and HPLC-DAD as luteolin, luteolin-7-glucoside, quercetin, quercetin-3-galactoside, kaempferol-3-galactoside, chlorogenic and isochlorogenic acids. Other phenolics were characterized by HPLC-DAD analysis: gallic, protocatechuic, caffeic, ferulic and isoferulic acids, quercetin-3-glucoside and luteolin-4′-glucoside.

The new CERN-ISOLDE on-line mass-separator facility at the PS-Booster

1992

The ISOLDE on-line isotope separators have been operated since 1967 at the CERN-SC. This 600 MeV proton synchro-cyclotron had to be shut down in December 1990 after 33 years of service and it was decided to move ISOLDE to a new experimental area. The new on-line mass-separator facility is now under construction at the CERN PS-Booster. This accelerator provides an average current of about 2-mu-A of 1 GeV protons in very short high intensity pulses at low repetition rate. The beam can hit either one of the two target stations, the general purpose separator (GPS), a reconstructed ISOLDE-2 type machine (which can deliver beams simultaneously into three beam lines), and the high resolution separ…

Step algebras of quantum sl(n)

1992

Phylogenetic analysis of the thiolase family. Implications for the evolutionary origin of peroxisomes

1992

The thiolase family is a widespread group of proteins present in prokaryotes and three cellular compartments of eukaryotes. This fact makes this family interesting in order to study the evolutionary process of eukaryotes. Using the sequence of peroxisomal thiolase from Saccharomyces cerevisiae recently obtained by us and the other known thiolase sequences, a phylogenetic analysis has been carried out. It shows that all these proteins derived from a primitive enzyme, present in the common ancestor of eubacteria and eukaryotes, which evolved into different specialized thiolases confined to various cell compartments. The evolutionary tree obtained is compatible with the endosymbiotic theory fo…

Applicability of a simple model for computing diffuse solar radiation to locations of the European, African, Asian and North American areas

1992

Abstract It is tested if the correlation type D = K(s/S)−0.25 (sin hn)1.55, 0.2 ⩽ s/S ⩽ 0.9 previously proposed by Coppolino for Italian locations using K = 7.0, allows a reliable estimation of the monthly mean daily diffuse solar radiation D (MJ m−2 day−1), from only the monthly mean daily relative sunshine s/S and the noon altitude of the sun on the 15th of the month hn (degrees) at locations of the European, African, Asian and North American areas. The test is performed at 14 stations in the above areas displaced at various latitudes L, elevations above sea level E and geographical situations, using K = 7.0 for the stations where 0.48 ⩽ (s/S)m, ⩽ 0.63, K = 8.5 for those where 0.40 ⩽ (s/S…

Oral 5-aminosalicylic acid (Asacol) in the maintenance treatment of Crohn's disease

1992

A randomized, placebo-controlled multicenter trial was conducted to evaluate the efficacy and safety of a delayed-release formulation of 5-aminosalicylic acid (5-ASA) (Asacol; GiulianiBracco, Milan, Italy) for prevention of clinical relapse in 125 patients with inactive Crohn's disease. Patients in remission [Crohn's Disease Activity Index (CDAI) less than 150] between 3 months and 2 years were randomly allocated to receive either 800 mg 5-ASA three times daily (n = 64) or placebo (n = 61) for up to 12 months or until relapse of symptoms. Relapse was defined by a CDAI greater than 150, with a minimum increase of 100 points over the baseline value. The cumulative relapse rates were 12% in th…

Measurement of the transition dipole moment of silane 28SiH4 by diode laser spectroscopy

1992

Abstract A tunable diode laser IR spectrometer which is being used in various molecular spectroscopy experiments is described. Absorption spectra observed in the ( ν 1 , ν 3 ) dyad of silane 28 SiH 4 yield estimates of two parameters of the dipole moment operator responsible for absorbance in this region.

Microstructural sensitivity of local porosity distributions

1992

The recently introduced concept of local porosity distributions for the geometric characterization of arbitrary porous media is scrutinized using computer generated pore space images. The paper presents the first direct determination of local porosity distributions from digital images. Pore space images with identical two point correlation functions are employed to analyse the geometrical sensitivity of the local porosity concept. The main finding is that local distributions can be used to discriminate between images which are indistinguishable using standard correlation functions. We also discuss the question of length scales associated with the local porosity concept.

Very high sensitivity in collinear laser spectroscopy: resonance detection by particle counting techniques

1992

Abstract Fast-beam collinear laser spectroscopy with resonance detection by counting of fluorescence photons provides a versatile tool for precise determinations of nuclear ground-state properties. The intrinsic high sensitivity of this method can be further increased by almost three orders of magnitude if measuring schemes based on ion or atom counting are introduced. The optical pumping from one atomic state to another at an appreciably different excitation energy is detected via state-selective collisional charge exchange processes and charge-state separated atom or ion counting. Applications of these techniques on alkaline earth, noble gas, mercury and thallium beams is examined.

Synthesis and structure verification of two previously uncharacterized pentachlorobiphenyls: PCB 108 and PCB 127

1992

Abstract The synthesis and structure verification of two previously uncharacterized polychlorinated biphenyl (PCB) congeners mono- ortho -substituted 2,3,3′,4,5′-pentachlorobiphenyl (PCB 108) and non- ortho -substituted 3,3′,4,5,5′-pentachlorobiphenyl (PCB 127) is described. The synthesis was done by the method of aromatic arylation in the presence of isopentyl nitrite. The purification and separation of the compounds was done by flash-chromatography on Al2O3- and charcoal columns. The structures were verified by 1H NMR, 13C NMR, IR and mass spectroscopy.

Pointwise resolutive significance of data and applications in experimental design and data treatment

1992

Abstract The concept of the resolutive significance of a point in a data set with regard to a number of addressed parameters is introduced, and two algorithms able to measure it are proposed. The algorithms are validated using simulated experiments. The sum of all the pointwise resolutive significances of a data set is also proposed as a measure of the resolution of the data set. This sum correlates well with the reciprocal of the standard deviation of the fitted parameters, indicating the precision that can be expected for each parameters. Applications in experimental design, and a method for establishing the weights in the least-quarters regression analysis are discussed.

A Vector Approach to Euler's Line of a Triangle

1992

Among the many interesting properties that triangles possess there is one that quickly attracts our curiosity and stays easily in our mind: The centroid, circumcentre and orthocentre all lie in a common line (Euler's Line). An elementary simple proof can be obtained using metric and affine properties of the points involved, [1]. Our aim here is to illustrate a proof using vectors. We identify points in the plane with their position vectors. It is easy to see that the centroid G of the triangle ABC is given by the identity

Thermal Lens Spectrometric Detection of Catecholamines after Oxidation to Aminochromes

1992

Abstract Experimental conditions for the spectrophotometric and thermal lens spectrometry (TLS) detection of catecholamines after oxidation to aminochromes with hexacyanoferrate (III) are optimized. At the low concentrations used in TLS, and in a 0.07 M citrate buffer, catecholamine oxidation can be performed at pH 7 and is immediate, whereas a lower pH value is required in spectrophotometry to avoid aminochrome polymerisation, the oxidation reactions being much slower. Similar TLS sensitivities are obtained for all catecholamines which facilitates HPLC evaluation. Sensitivity can be enhanced using a 50% ethanol-water medium. The linear dynamic range extends over two orders of magnitude, th…

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1992

Zwitterionic polymers [CH 2 CR(COOR')] n (R= H, Me; R'= (CH 2 ) 11 + NMe 2 (CH 2 ) 3 SO 3 - , (CH 2 ) 2 + N(CH 3 )([CH 2 ] 3 SO 3 - )C 10 H 21 ) are studied by X-ray scattering. The structural order both in the short-range and long-range scale is investigated. The influence of the polymer backbone, of different locations of the ionic groups in isomeric polymers, of bound water and of added inorganic salts on the bulk structures is studied, and the observed rearrangements are analysed

Chlorocymenes, cymenenes and other chlorohydrocarbons in pulp mill effluents, sludges and exposed biota

1992

Abstract Polychlorinated cymenes (PCYMS) and cymenenes (PCYMD) were analyzed by GC/LRMS/SIM in effluents and sludges of three different pulp mills and in fish and mussels exposed to pulp mill effluents. The levels of PCYMS+PCYMD were 0.3–4.8 μg/l in total effluents,

DiP223: Strongly temperature dependent electro-optic coefficients in BaTiO3

1992

Abstract By means of a Senarmont set up and a very sensitive method, electrooptic coefficients in BaTiO3 are accurately determined from the phase measurement of the retardation Γ due to the electric field induced birefringence of the crystal. Electro-optic properties are investigated as a function of temperature around room temperature. A very large value of the coefficient r42 is found, in agreement with previous investigations. In addition, this coefficient is shown to be very sensitive to the temperature even for a very small change. The importance of both the thermo-optic effect and the thermal variation of electro-optic properties is pointed out for device applications of BaTiO3.

A PARALLEL ALGORITHM FOR ANALYZING CONNECTED COMPONENTS IN BINARY IMAGES

1992

In this paper, a parallel algorithm for analyzing connected components in binary images is described. It is based on the extension of the Cylindrical Algebraic Decomposition (CAD) to a two-dimensional (2D) discrete space. This extension allows us to find the number of connected components, to determine their connectivity degree, and to solve the visibility problem. The parallel implementation of the algorithm is outlined and its time/space complexity is given.

CT-Diagnostik von Blutungen in die Muskulatur des Abdomens im Rahmen therapeutischer Eingriffe in das Gerinnungssystem

1992

Eleven patients treated by anticoagulants or lytic therapy suffered bleeding into the abdominal muscles, resulting in neurological symptoms or those of an acute abdomen. By means of CT it was possible to demonstrate the bleeds and to clarify the differential diagnosis, thereby leading to correct treatment. The possibility of early diagnosis of haemorrhages makes CT a suitable and reliable method.

Battered child syndrome: cerebral ultrasound and CT findings after vigorous shaking.

1992

Child abuse by whiplash-shaking can lead to severe cerebral damage, neurological defects and mental retardation. Cerebral damage has been found with and without external evidence of head injury. We report the sonographic findings in two children after traumatization due to repetitive vigorous whiplash shaking. Cerebral sonography revealed cerebral edema at admission or within 48 hours thereafter. Follow-up studies demonstrated development of marked brain atrophy in both cases. The sonographic findings were confirmed by cranial computerized tomography. Doppler sonography was used to monitor cerebral perfusion by measuring intracranial blood flow. The clinical history of the patients demonstr…

Effect of gemfibrozil treatment on fibrinolysis system in patients with hypertriglyceridemia

1992

Abstract The effect of gemfibrozil on lipidic, coagulative, and fibrinolytic pattern was studied in 20 patients with primary type IV hyperlipoproteinemia. After a 4-week stabilization period during which administration of lipid-lowering drugs was stopped and an isocaloric diet (20% protein, 30% fat, and 50% carbohydrates) was prescribed, 20 patients (12 men and 8 women; mean age, 38 ± 4 years; body mass index, 23.4 ± 1.5) suffering from primary hypertriglyceridemia were included in this study and treated for a 12-week period with gemfibrozil (600 mg BID). Every 4 weeks the following parameters were checked: glycemia, triglycerides, total cholesterol, high density lipoprotein-cholesterol, to…

Chemotherapy in head and neck cancer (I): Management of recurrent or metastatic disease

1992

SummaryThis paper is an up-dated review of the role of systemic chemotherapy in the management of recurrent and/or metastatic head and neck carcinoma.

Electrophoretic analysis of heterogeneous lipopolysaccharides from various strains of Vibrio vulnificus biotypes 1 and 2 by silver staining and immun…

1992

Lipopolysaccharides (LPS) of 11 strains of Vibrio vulnificus biotypes 1 and 2, isolated from an eel farm, and of 10 reference strains, were examined by SDS-polyacrylamide gel electrophoresis coupled with silver staining and immunoblotting. LPS samples were obtained from whole-cell lysates, outer membrane fragments, and extracellular products. By silver staining, only a diffuse band of low-molecular weight could be visualized in all cases except for a biotype 1 strain isolated from water. However, immunoblotting with antisera obtained against strains of biotypes 1 and 2 from eels allowed visualization of multiple O-polysaccharide chains. All biotype 2 strains, independently of their origins,…

Collection, cooling and delivery of ISOL beams

1992

Abstract The collection of an ISOL beam in a Penning trap using implantation on a surface that is subsequently manipulated so as to become part of an end electrode of a Penning trap and reionization of the implanted material by heat has already been very productive for high-precision nuclear-mass measurements, even though it is limited to elements that are surface ionizable and the collection efficiencies are never better than about 0.1%. More recently, in 1990 a Paul trap system for electric collection of ions was installed at the ISOLDE-3 facility and collection was demonstrated for a 60 kV beam of 132 Xe ions. The purpose of this test setup was to determine the relationship between phase…

Column switching and high-performance liquid chromatography in the analysis of amitriptyline, nortriptyline and hydroxylated metabolites in human pla…

1992

A column-switching system for the direct injection of plasma or serum samples, followed by isocratic high-performance liquid chromatography and ultraviolet detection, is described for the simultaneous quantitation of the tricyclic antidepressant amitriptyline, its demethylated metabolite nortriptyline and the E- and Z-isomers of 10-hydroxyamitriptyline and 10-hydroxynortriptyline. The method included adsorption of amitriptyline and metabolites on a reversed-phase C8 clean-up column (10 microns; 20 mm x 4.6 mm I.D.), washing of unwanted material to waste and, after on-line column-switching, separation on a cyanopropyl analytical column (5 microns; 250 mm x 4.6 mm I.D.). The compounds of inte…

Quinone reduction and redox cycling catalysed by purified rat liver dihydrodiol/3 alpha-hydroxysteroid dehydrogenase.

1992

A highly active preparation of rat liver dihydrodiol/3 alpha-hydroxysteroid dehydrogenase was obtained using a newly developed, rapid purification scheme involving affinity chromatography on Red Sepharose. Depending on the coenzyme present, the purified enzyme was found to catalyse the oxidation of dihydrodiols and steroids or the reduction of substrates with carbonyl or quinone moieties. Using a wide range of synthetic quinones derived from polycyclic aromatic hydrocarbons (PAHs), we observed a pronounced regioselectivity of the quinone reductase activity. Good substrates were the o-quinones of phenanthrene, benz(a)anthracene, chrysene and benzo(a)pyrene with the quinonoid moiety in the K-…

Characterization of cryopreserved rat liver parenchymal cells by metabolism of diagnostic substrates and activities of related enzymes

1992

The metabolism of testosterone and benzo(a)pyrene (BaP) which is mediated by diverse enzymes was determined in cryopreserved rat liver parenchymal cells and compared with that found in freshly isolated cells. In addition, the activities of single xenobiotic-metabolizing enzymes were measured by using specific substrates. The cytochrome P450 (P450)-mediated total metabolic conversion of testosterone was reduced to 55% in cryopreserved cells. The metabolite profile, i.e. the formation of single metabolites compared with total metabolic conversion, was however unchanged when compared with freshly isolated cells. A concomitant reduction in the activities of the involved P450 isoenzymes can ther…

ac conductivity inLa2CuO4

1992

Measurements of the complex ac conductivity are reported for a single crystal of ${\mathrm{La}}_{2}$${\mathrm{CuO}}_{4}$ for frequencies ${10}^{2}$\ensuremath{\le}\ensuremath{\nu}\ensuremath{\le}${10}^{9}$ Hz and temperatures 25\ensuremath{\le}T\ensuremath{\le}300 K. The conductivity follows a power-law behavior ${\mathrm{\ensuremath{\omega}}}^{\mathit{s}}$ with the frequency exponent s independent of temperature and independent of frequency. However, the hopping transport is strongly anisotropic, with s\ensuremath{\approxeq}0.75 within the ${\mathrm{CuO}}_{2}$ planes and s\ensuremath{\approxeq}0.25 perpendicular to the planes.

Relation entre la composition en acides aminés libres des graines de fenugrec et la qualité aromatique

1992

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Chromosomal abnormalities in Waldenström's macroglobulinemia

1992

We report the results of cytogenetic studies of direct bone marrow (BM) preparations and of short-term BM and peripheral blood (PB) cultures from 17 patients with Waldenström's macroglobulinemia. We noted clonal chromosome changes in 10 patients. Abnormalities affected chromosomes X, Y, 2, 4, 5, 15, 16, 18, 19, 20, 21, and 22; in particular, chromosomes 2, 4, and 5 were involved in structural changes: a homogeneously staining region [hsr(2)], a der(4)t(4;?)(q32;?), and a 5q+. The other chromosomes were involved in numerical abnormalities, such as pseudodiploidy (a 46,X,-X,+15 clone), loss of chromosome Y, and monosomy of chromosomes 16, 18, 19, 20, 21, and 22. Nonclonal chromosome rearrange…

Inhomogeneous space-times admitting isotropic radiation: Vorticity-free case

1992

The energy-momentum tensor of space-times admitting a vorticity-free and a shear-free timelike congruence is obtained. This result is used to write Einstein equations in a convenient way in order to get inhomogeneous space-times admitting an isotropic distribution of photons satisfying the Liouville equation. Two special cases with anisotropic pressures in the energy flow direction are considered.

Computer simulation of disordering and premelting of low-index faces of copper.

1992

Molecular dynamics and the effective-medium theory have been applied to investigate the structure and dynamics of (110), (100), and (111) faces of copper in the whole temperature range from 0 K up to the bulk melting point, which has been determined to be 1240\ifmmode\pm\else\textpm\fi{}25 K. The observed order in the surface stability follows the order in the packing density. (110) disorders first via anharmonic effects (up to 700 K), then by vacancy-adatom formation and finally by premelting of the surface at about 1200 K. The (110) solid-melt interface is anisotropic and broadened, having a tendency to form small fluctuating (111) facets in equilibrium, which is suggested to be the atomi…