Helium burning of22Ne

1989

The22Ne(α, γ)26Mg and22Ne(α, n)25Mg reactions were investigated forE α(lab) from 0.71 to 2.25 MeV. Neon gas enriched to 99% in22Ne was recirculated in a differentially pumped gas target system of the extended type. Theγ-ray transitions were observed with Ge(Li) detectors and the neutrons with3He ionization chambers. A previously known resonance at ER(lab)=2.05 MeV was verified and 15 new resonances were found in the energy range covered, with the lowest at ER(lab)=0.83 MeV. Information on resonance energies, widths, strengths,γ-ray branching ratios, as well asJ π assignments, is reported. The energy range investigated corresponds to the important temperature range ofT 9 from 0.3 to 1.4 (109…

Total cross sections of reactions induced by neutron-rich light nuclei

1989

Total nuclear reaction cross-sections are determined by means of a 4π-γ method. The results cover a wide span of targets for various stable beams. The validity of the method is shown in a combined systematics including also the results of transmission-type experiments. The data are very well described by the formula developed by Kox et al. The same method is applied to secondary fragment beams produced from a 44 MeV/u22Ne beam on a 332mg/cm2 181Ta target. Using the LISE spectrometer the fragments4, 6He,6–9, 11Li,7, 9–12, 14Be,10–15, 17B11–19C,13–19N,15–21O,18– 21F and20,21 Ne are analyzed and transported to interact with a 199.4 mg/cm2 Cu target surrounded by a 4π-γ counter. The measured to…

Some observations on the determination of the methyl parathion-parathion ratio in binary mixtures by infrared spectroscopy

1989

Abstract The determination of the methyl parathion/parathion ratio in binary mixtures has been carried out by infrared spectroscopy using a simple and easy model for the treatment of the spectra obtained from sample thin films using sodium chloride windows. The model is based on the use of two bands, one at 974 cm−1, characteristic of parathion, and other at 1348 cm−1, common to both compounds. From the spectra of pure parathion samples and mixtures of known composition of methyl parathion and parathion, two constants have been obtained. These constants relate the absorption of each compound at 1348 cm−1 to the absorption of parathion at 974 cm−1. Eighteen synthetic samples have been analyz…

Permutation properties and the fibonacci semigroup

1989

Calculation of beta-decay properties of neutron-rich nickel isotopes

1989

Gamow-Tellerβ-decay properties of neutron-rich Ni isotopes have been calculated in the RPA with Nilsson model wave functions. On the basis of the results for the known isotopes67–69Ni, half-lives and neutron-emission probabilities for70–82Ni are predicted and compared to earlier model estimates. Possible implications onr-process nucleosynthesis are discussed.

Lifetime of the metastable 6P 3/2 level of PbII

1989

Pb+-ions were stored in a r.f.-quadrupole trap. Short laser pulses at a 710-nm M1-transition excited the ions to the metastable 6P 3/2 level. Time-resolved registration of the subsequent decay photons at the same wavelength directly gives the lifetime of that state. No dependence of the decay rate on the density of different buffer gases up to 10−5 mbar pressure was observed and from this we deduced upper limits to the quenching cross section. We have observed, however, a small dependence on the stored ion number. The final result for the lifetime is 41.2 ± 0.7 ms in agreement with the result of a previous calculation.

Risk factors of female cancers in Ragusa population (Sicily). 2. Breast cancer.

1989

A case-control study on breast, cervix and corpus uteri cancer cases registered in Ragusa between January 1, 1983 and June 30, 1985 has been conducted. Information on risk factors has been obtained by means of a structured questionnaire. Risk factors for breast cancer were: few pregnancies (1-2 vs greater than 4 OR 2.14, 95% CL 1.13-4.04), few children (for postmenopausal only, chi trend 4.84), previous breast disease (OR 1.97, 95% CL 1.20-3.23), family history (OR 3.57, 95% CL 1.92-6.63), alcohol (OR 1.68, 95% CL 1.12-2.53), high socioeconomical status (1 vs 4 OR 2.93, 95% CL 1.22-70.03). A protective role was evident for: early age at first birth (for premenopausal only, less than 20 vs g…

Micro-albuminuria as a predictor of cardiovascular damage in essential hypertension

1989

Spectrophotometric determination of cystine by formation of an o-phthalaldehyde/N-acetyl-l-cysteine derivative

1989

Abstract Cystine reacts with o -phthalaldehyde (OPA) in the absence and presence of a thiol compound to yield different compounds. The use of N -acetyl- l -cysteine as thiol leads to the formation of two derivatives, likely simple and double isoindoles, where the disulfide bond remains unbroken. In contrast, mercaptoethanol gives rise to the reduction of the amino acid to form a cysteine derivative. Obtaining cystine isoindoles makes it possible to spectrophotometrically determine the amino acid after Chromatographic separation and is further evidence of the large stabilization effect produced by N -acetyl- l -cysteine in the formation of OPA-thiol derivatives.

The transport of ions across monoolein bilayers mediated by synthetic macrocyclic carriers

1989

The efficiency as carriers for the alkali and the alkaline earth ions across monoolein bilayers of three macrocyclic compounds has been investigated by conductometric measurements. The results show that although the three compounds have the optimum cavity size for fitting potassium and barium cations, their efficiency in ionic transport is quite different. These discrepancies are rationalized on the basis of the overlap of the water-diazacrown and cation-ligand interactions on the carrier mechanism.

Ultracytochemical localization of Ca2(+)-ATPase activity in the middle ear mucosa of the guinea pig.

1989

Ca2(+)-ATPase activity was studied ultra-cytochemically in the middle ear mucosa of the guinea pig. On electron microscopic examination, the most intense reaction was found on the microvilli. Reaction products were also observed on the cilia and around and between the secretory granules on the apical side of the cells in their secretory phase. The basolateral membranes contained few reaction products, while very little or no activity was found on the basal membrane.

Experimental Determination of Weak Quark Mixing Angles in the Eight Quark Scheme

1989

Cycloaddition reactions of 1-tert-butyl-4-vinylpyrazole

1989

1-tert-Butyl-4-vinylpyrazole1 a reacts with dimethyl acetylenedicarboxylate (DMAD), methyl propiolate (MP) and N-phenylmaleimide (NPMI) affording the indazole derivatives2,3, and5 as a result of a Diels-Alder ([4 + 2]) cycloaddition. With diethylazodicarboxylate (DEAZD), tetracyanoethylene (TCNE) and 4-phenyl-1,2,4-triazole-3,5-dione (PTAD) the reaction takes place exclusively through the olefinic substituent and the adducts6,7, and9 were isolated. The alkenylpyrazoles1 b–d reacted withDMAD and N-phenylmaleimide to give polymers.

Fast volatilization of some lanthanide and actinide elements from titanium surfaces

1989

The ad- and desorption of trace quantities of the lanthanide elements lanthanum, praseodymium, neodymium, samarium, europium, gadolinium, dysprosium, and ytterbium and of the actinide elements americium and curium were investigated by thermochromatographic and isothermal measurements with hot titanium columns. The adsorption enthalpies deduced from the experimental data are in reasonable agreement with calculated values which indicate considerable variations in volatility under such conditions. More volatile elements can quickly be separated from less volatile elements by heating the mixture on titanium in high vacuum.

Duality for constrained multifacility location problems with mixed norms and applications

1989

A dual problem is developed for the constrained multifacility minisum location problems involving mixed norms. General optimality conditions are also obtained providing new algorithms based on the concept of partial inverse of a multifunction. These algorithms which are decomposition methods, generate sequences globally converging to a primal and a dual solution respectively. Numerical results are reported.

Nephro-broncho-cutaneous Fistula

1989

Polar relaxation mode in pure and iron-doped barium titanate

1989

A dielectric relaxation peak is reported in ${\mathrm{BaTiO}}_{3}$ and in ${\mathrm{BaTi}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Fe}}_{\mathrm{x}}$${\mathrm{O}}_{3}$. It is nearly monodispersive, centered in the ${10}^{8}$-Hz range, and slowest at the transition temperature ${T}_{c}$\ensuremath{\simeq}413 K from the cubic to the tetragonal phase. Iron doping lowers ${T}_{c}$ and slows down this relaxation mode.

UNA RARITA' ISTOLOGICA IN ONCOLOGIA PEDIATRICA: L'EMANGIOPERICITOMA MALIGNO CONGENITO.

1989

Gli Autori riportano un caso di Emangiopericitoma congenito a rarissima localizzazione retroperitoneale. Dopo revisione della letteratura e discussione del caso, si evidenziano le difficoltà diagnostiche nei confronti di altre masse retroperitoneali ed il ruolo preminente della chirurgia nella terapia di queste neoplasie.

Effect of different doses of ursodeoxycholic acid in chronic liver disease

1989

Recent clinical studies have indicated that ursodeoxycholic acid (ursodiol), administered at dosages ranging between 10 and 15 mg/kg/day, improves liver function indices in both cholestatic and inflammatory chronic liver diseases. These dosages would be considered high for the use of ursodiol in gallstone dissolution therapy. To investigate the dose-response relationship to ursodiol administration, we planned a few studies in patients with primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), and chronic hepatitis (CH). Patients with PBC were subdivided into two groups on the basis of their serum bilirubin values, with 2 mg/dl as the dividing line. Ursodiol was given at dos…

Expression of keratin 5 as a distinctive feature of epithelial and biphasic mesotheliomas. An immunohistochemical study using monoclonal antibody AE1…

1989

In previous biochemical analyses, keratin 5 (Mr 58,000) has been detected in most mesotheliomas with epithelial component but not in pulmonary adenocarcinomas (Blobel et al., Am J Pathol 121: 235-247, 1985). In the present study, we have characterized a monoclonal antibody, AE14, as being selectively specific for keratin 5 (apart from the reactivity with certain hair proteins) as shown by immunoblotting of gel-electrophoretically separated proteins from various tissues. Immunohistochemical screening of a variety of normal human tissues, using immunoperoxidase microscopy on cryostat sections, revealed the binding of this antibody to the basal, immature cells of stratified squamous epithelia,…

Structural variations of liquid crystalline polymers with phasmidic-type mesogens

1989

Abstract The fixation of phasmidic-type mesogens through spacer groups to polysiloxane backbones provided a method of obtaining liquid crystalline polymers with phasmidic mesogens as side groups. The polymer 6b showed a bilayer structure in the mesophase range. The tendency to form liquid-crystalline phase depends on the number and the length of alkoxy substituents.

Endoluminal sonography in follow-up of rectal carcinoma.

1989

Fourteen patients who had undergone local excision, anterior resection or low anterior resection for rectal carcinoma were examined by endoscopic ultrasonography. In two of three cases of local recurrent carcinomas, endoscopic sonography was superior to computed tomography in determining the depth of tumor infiltration. There were difficulties in differentiating scar tissue from local tumor formation when the mucosa appeared normal upon endoscopic examination. Only repeated follow-up examinations starting in the postoperative period, will allow a differentiation between scar tissue and local tumor recurrence.

Proliferating tricholemmal tumour with lymph node metastases

1989

SUMMARY A 42-year-old woman with a proliferating tricholemmal tumour (PTT) with regional lymph node metastases is reported. Histochemical studies showed evidence of tricholemmal keratinization. There was recurrence following excision and subsequently the patient developed lymph node metastases.

Immune blot analysis of viral surface proteins in serum and liver of patients with chronic hepatitis B virus infection

1989

The small and the middle surface proteins of hepatitis virus form either the virion or the 22 nm particle both of which are secreted. The large surface protein by itself remains cell bound in artificially transfected cell culture unless it is accompanied by an excess of the smaller protens. Its behavior in vivo is not yet well studied. Using specific monoclonal antibodies for immunoblotting, we found an abundance of small surface protein in the serum of chronic virus carriers and moderate amounts in the liver irrespective of viremia. The large surface protein was present in the serum and the liver of viremic carriers. In nonviremic carriers, the large protein was absent from serum, but in t…

Effects of Different Glucose Concentrations on Spinal Anaesthesia with Bupivacaine and Tetracaine

1989

The effects of 5% and 8% glucose in 0.5% tetracaine or bupivacaine on the anaesthetic spread were investigated in 80 urological patients requiring spinal anaesthesia for trans-urethral resection of the prostate. The local anaesthetic solutions were randomly administered, the patients being divided into four groups of 20, and the anaesthetic profile was then evaluated in a double-blind fashion by an independent observer. Maximum cephalad spread of analgesia was significantly greater with tetracaine in 8% glucose compared to the other three groups (tetracaine/5% glucose, bupivacaine/5 or 8% glucose) (P less than 0.05). Glucose concentration significantly influenced spreading characteristics o…

Crystal Data for Nickel Cimetidine Chloride: Ni (CM)2 CL2·2H2O

1989

AbstractNickel Cimetidine Chloride, Ni(C10H16SN6)2Cl2·2H2O has been investigated by means of X-ray powder diffraction. Unit cell dimensions were determined by indexing programs, from diffractometer data obtained with copper radiation. A primitive monoclinic cell was found: a = 11.836(3)Å, b = 13.322(5)Å, c = 10.487(2)Å, β = 113.08 (2)°, Z = 2, Dx = 1.462 g/cm3, M.W. = 670.32. These data are consistent with values reported in the literature for other cimetidine complexes.

Capital humano y formación de rentas

1989

International audience

Group analysis and similarity solutions of the compressible boundary layer equations

1989

In this paper the application of Lie's methods to the equations of the laminar boundary layer is discussed. The momentum and energy equations in Prandtl's form are considered for a steady, viscous, compressible laminar flow with non zero pressure gradient, variable viscosity and thermal conductivity. Group analysis yields similarity solutions for given pressure distributions and particular values of the invariance group parameters (group classification). Crocco's transformation is obtained for the infinite-dimensional group of the Lie's algebra admitted by the equations.

A comparative assay of epidemiological markers for Acinetobacter strains isolated in a hospital.

1989

Summary A comparative assay for epidemiological evaluation of three different Acinetobacter typing procedures, i.e. biotyping, phagetyping, and the analysis of the bacterial envelope protein profiles, was carried out using sixty-four multiresistant Acinetobacter strains isolated from clinical specimens. The antibiotic susceptibility of the strains was also considered. After genospecies identification, biotyping allowed the recognition of a relatively large and long-lasting presence, at an Intenive Therapy Unit, of two A. baumannii biotypes. Phage-typing and the analysis of the susceptibility to antibiotics allowed for the differentiation of strains belonging to different genospecies and bio…

Possible association of sudden infant death with partial complement C4 deficiency revealed by post-mortem DNA typing of HLA class II and III genes

1989

Based on evidence of an increased rate of respiratory infections in sudden infant death (SID) infants as well as the observation of familial occurrence, we analysed in a retrospective study class II and class II genes of the major histocompatibility complex in 40 cases of SID by Southern blot analysis of DNA obtained post mortem from tissue samples. In 24 cases, the parents were interviewed and confirmatory human lymphocyte antigen (HLA) and DNA typing was carried out. Using HLA-DR beta and -DQ beta probes, no evidence of an abnormal HLA-DR frequency distribution in SID infants was detected (P = 0.97). Using DNA probes for the tandemly arranged complement C4 and steroid 21-hydroxylase genes…

Electromagnetic properties of neutrinos in a background of electrons.

1989

Using covariant methods we calculate the neutrino electromagnetic vertex in a gas of electrons to lowest order in a loop expansion and to the lowest order in $\frac{1}{{M}_{W}^{2}}$. The new induced terms, while they are chirality preserving, yield additional contributions to the dipole moments in the nonrelativistic limit. These are identical for particles and antiparticles and so need not vanish for Majorana neutrinos. As applications of our formulas, the expression for the $\mathrm{plasmon}\ensuremath{\rightarrow}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ decay rate is rederived and the dispersion relation of a massless neutrino propagating in matter in the presence of an external magn…

Role of the gamma-glutamyl cycle in the regulation of amino acid translocation

1989

Amino acid translocation was studied in the mammary gland of lactating rats and in the placenta of pregnant rats. The uptake of amino acids by the mammary gland is maximal on days 10-14 of lactation and is minimal on days 19-21. However, on day 19 maximal uptake can be restored by injection of 1) small amounts of gamma-glutamyl amino acids, 2) 5-oxoproline, and 3) an inhibitor of 5-oxoprolinase. A severe decrease in uptake of amino acids at the peak of lactation is provoked by anthglutin, an inhibitor of gamma-glutamyltranspeptidase (GGT). Simultaneous injection of 5-oxoproline blocks these effects of anthglutin. In pregnant rats, inhibition (79%) of placental GGT activity by acivicin resul…

Active immunization of homosexual men using a recombinant hepatitis B vaccine

1989

Twenty homosexual men [13 anti-human immunodeficiency virus (HIV)-positive, seven anti-HIV negative] without HBsAg, anti-HBs, and anti-HBc were vaccinated with three 20 micrograms doses of a recombinant hepatitis B vaccine. All anti-HIV-positive homosexuals were nonresponders independent of the initial number of CD4-positive cells. Among seven anti-HIV-negative individuals, five responded. After three doses of the vaccine, CD4-positive cells fell in anti-HIV positive individuals by 22.4%. A similar fall in CD4-positive cells of an average 24.9% was noted in 17 matching, but nonvaccinated, anti-HIV-positive homosexuals. The study indicates that the efficacy of vaccination in anti-HIV-positiv…

Das Experiment: Trichromatische Theorie des Farbensehens

1989

Adsorptionsvoltammetrische Molybd�nbestimmung in biologischen Proben nach nassem Hochdruckaufschlu\

1989

The transfer of an (known from literature [141 and till now only applied to seawater) adsorption-voltammetric determination of molybdenum with oxine to biological samples, is described. The herewith accomplished changes of base solution resulted simultaneously in an optimization of the method with regard to interpretability and sensitivity. Special care was taken in the problem of decomposition. Best results are obtained with a high-pressure decomposition. Accuracy of analyses is confirmed with trials of recovery also in the biological matrix.

Cellular and Subcellular Localization of Peroxidase Isoenzymes in Plants and Cell Suspension Cultures from Lupinus polyphyllus

1989

Abstract , leaf protoplasts and cell suspension cultures of Lupinus polyphyllus and isolated vacuoles were studied for cellular and subcellular localization of peroxidase isoenzymes. Isoelectric focusing revealed 16 peroxidase isoenzymes. The basic peroxidase isoenzymes are predominantly localized in the vacuole and, to a minor degree, unbound in the intercellular space. The acidic isoenzymes are cell wall-bound in plants and not detectable in suspension-cultured cells. Large amounts (up to 11.0 U/ml) of a single basic isoenzyme are detectable in the spent medium of cell suspension cultures.