Rickettsiae of the spotted fever group in dog fleas (Ctenocephalides spp.) in Western Sicily

1989

Effects of combined hand-arm vibration and cold on skin temperature

1989

Under laboratory conditions 14 healthy male subjects were exposed to hand-arm vibration (ahzw = 6.3 m/s2) at different air temperatures (5 degrees, 12 degrees, 18 degrees and 25 degrees C). Static load (grip force 15 N, push force 40 N) was kept constant. Finger tip temperature as an indirect criterion of the peripheral blood circulation was measured. As expected, low air temperatures (5 degrees, 12 degrees and 18 degrees C) cause a strong decrease of skin temperature. Under additional stress of vibration connected with static load, a further decrease of the mean skin temperature was noted. At this, static load proved to have a predominant influence on the acute diminution of skin temperatu…

Relativistic multipole operators for semileptonic weak and electromagnetic nuclear reactions.

1989

We discuss multipole operators that arise in a relativistic analysis ofsemileptonic weak and electromagnetic interactions with nuclei. Thesesingle-particle operators are evaluated between relativistic nucleon boundstates that are solutions to the Dirac equation with potentials of the formproduced by the sigma-..omega.. model. The reduced matrix elements aregiven in terms of easily programmable radial integrals and can be applied to anumber of reactions such as elastic and inelastic electron scattering, realphoton processes, ..beta.. decay, and charged lepton capture as well as moreexotic interactions such as charged and neutral current neutrino reactions. Asa specific example, we calculate …

Effects of cromakalim on acetylcholine release and smooth muscle contraction in guinea-pig small intestine

1989

The effects of the potassium channel opener cromakalim on smooth muscle contraction and 3H-acetyl-choline release were studied simultaneously in guinea-pig longitudinal muscle myenteric plexus preparations which had been preincubated with 3H-choline. Cromakalim (10 mumol/l) inhibited more markedly the smooth muscle contractions caused by the release of endogenous acetylcholine (via electrical stimulation or via activation of nicotine- and 5-HT3-receptors) than contractions induced by pilocarpine. Cromakalim (10 mumol/l) did not affect the release of 3H-acetylcholine evoked by electrical stimulation or by stimulation of nicotine- and 5-HT3-receptors. In contrast, the release of 3H-acetylchol…

Acquired C1 inhibitor (C1-INH) deficiency type II. Replacement therapy with C1-INH and analysis of patients' C1-INH and anti-C1-INH autoantibodies

1989

Abstract The response of two patients with autoantibody-mediated C1-inhibitor (C1-INH) deficiency to replacement therapy with C1-INH was studied over a period of 3 d. In patient 1 an acute attack of angioedema was successfully managed by infusion of 1,000 U of C1-INH concentrate. C1-INH function returned to normal levels within 30 min, while CH50 and C4 peaked after 6-7 h and C1 hemolytic activity reached 50-60% of normal after 3 d. Immediately after the injection an increase in C1-INH-anti-C1-INH complexes was observed. Based on NH2-terminal sequence analysis of the patients' Mr 96,000 C1-INH, it is concluded that this fragment is generated after cleavage of C1-INH in its active site by on…

An alternative simple approach to estimate atmospheric correction in multitemporal studies

1989

Abstract Studies that use multitemporal images require the conversion of original digital data into the corresponding physical magnitudes. Atmospheric correction is one of the most important steps in this process, which is usually undertaken using atmospheric radiative transfer models. The main difficulty in these models is the need of atmospheric input data which are not usually available. An alternative approach to atmospheric correction is proposed in this Letter. It is based on the idea that the atmospheric effects over two or more dates can be determined in a relative way, by using the apparent reflectance values of surfaces whose ground reflectance can be considered unchangeable with …

Helium isotopes and tectonics in southern Italy

1989

Geodynamic evolution of southern Italy can be understood within the framework of the Mediterranean-Alpine System. Subduction of a plate along the Sicily-Calabrian forearc under the Tyrrhenian Sea has been suggested by many geophysicists, although it is not yet confirmed and remains somewhat controversial. Helium isotope ratios provide useful information on the geotectonic structure of the region. The authors report here the {sup 3}H/{sup 4}He ratios of terrestrial gas samples from southern Italy. The observed {sup 3}He/{sup 4}He ratios are relatively high in the Eolian volcanic arc region and low in the other areas. Dichotomous explanations are presented. Firstly, volcanic arc-forearc hypot…

PETROLOGIA DOS RODINGITOS DO COMPLEXO MÁFICO-ULTRAMÁFICO DE CANA BRAVA, GOIÁS

1989

Effects of tumor necrosis factor-alpha on tumor blood flow and hyperthermic treatment.

1989

The impact of recombinant human tumor necrosis factor-alpha (rhTNF-alpha), given alone or in combination with local hyperthermia, on perfusion and growth of a moderately rhTNF-alpha-sensitive rat tumor (DS-carcinosarcoma) was investigated. DS-carcinosarcomas were implanted into the hind foot dorsum of Sprague-Dawley rats. Tumor blood flow (TBF) was measured with the krypton-85 clearance technique. Treatment with either tumor necrosis factor-alpha (0.1-1.0 mg/kg) or hyperthermia (43.3 and 44.3 degrees C, 40 min) can decrease the perfusion of malignant tumors. The TBF reduction was fully established 2 h after rhTNF-alpha injection and lasted for at least 4 h. The application of local hyperthe…

Quadrupole splitting of Fe(II) spin crossover compounds study of temperature and pressure dependence and the implication for the interaction mechanism

1989

The temperature and pressure dependence of the quadrupole splitting ΔE Q of the 3/2→1/2 nuclear Mossbauer transition of57Fe in the spin crossover compounds [Fe x Zn1−x (2-pic)3]Cl2⋆EtOH and the deuterated analog [Fe x Zn1−x (2-pic-ND2)3] Cl2⋆EtOD (2-pic=2-picolylamine) have been studied. The change of ΔE Q can be linearly related to the defomation of the lattice as observed by X-ray measurements. The dependence of ΔE Q on temperatureT, pressurep, and the fraction γ of molecules in the electronic high spin state in the pure iron (x=1) compounds is therefore interpreted as a result of the change of the lattice contribution to the electric field gradient (EFG) at the nucleus only. The intrinsi…

A Comparative Study of Blood Lactate Tests in Swimming*

1989

Three different modes of lactate tests were studied. Eleven male competitive swimmers performed the tests (n.100 m, n.300 m, 2.100m + 2.400 m) within 5 days. Swimming velocity (V) vs blood lactate (BLa) and V vs heart rate (HR) curves were averaged. In V vs BLa comparisons, the BLa values of 4 mmol.l-1 in 2.400 m, 3 mmol.l-1 in n.300 m, and 2 mmol.l-1 in n.100 m modes were found to correspond to the same V. Although the resting BLa values were similar before the testing occasions, the initial BLa value in very easy swimming was lower in the n.300 m than in the n.100 m mode. The elimination of lactate most probably caused this difference. The highest BLa value was measured in the n.100 m (14…

Reinfarction Related to PTCA-Induced Coronary Embolism after Successful Thrombolytic Therapy

1989

Coronary embolism originating from residual thrombotic material is one of the complications arising during acute percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction. This case report describes a symptomatic embolization of the right posterolateral and right posterior descending branch during success-ful PTCA of a subtotal stenosis of the midright coronary artery after acute inferior myocardial infarction. Typical ECG signs of reinfarction were recorded. We succeeded in recanalizing these branches by superselective thrombolysis and angioplasty.

Teacher stress during a school year: Covariance and mean structure analyses

1989

This study examined teacher stress over a school year. A total of 142 teachers made repeated assessments (12 in all) of the stress indicators by answering questionnaires during the school year of 1983–1984. Longitudinal quasi-simplex models and modifications of these were constructed for the analysis of the structural features of the teacher stress process over a school year. By using these models all the stress data could be analysed at the same time in a statistically efficient way. According to the constructed models, teacher stress was a stable process during terms, which meant that the variance in latent stress in the measurements was well explained by the previous measurement. The Chr…

Action of anticonvulsants on hippocampal slices in Mg-free medium

1989

The effects of six prototype anticonvulsant drugs were investigated on epileptiform field potential discharges evoked in hippocampal slices of rats by removing magnesium ions from the perfusion fluid in order to reveal a possible interaction with N-methyl-D-aspartate (NMDA) receptor activation. All drugs reduced the multiple discharges with the following order of potency: midazolam greater than carbamazepine = phenytoin = phenobarbital greater than ethosuximide = valproate. They had a stronger depressant effect on the later population spikes but none of them abolished the epileptiform discharge. These effects can be explained by known mechanisms of action of the anticonvulsants tested and l…

Gill ATPase activity in Procambarus clarkii as an indicator of heavy metal pollution.

1989

Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues, including heavy metals, from the many urban and waste waters of this area. The American red crayfish, Procambarus clarkii have a high resistance to toxic effects of heavy metals. The sublethal effects of heavy metals on gills of fish and aquatic invertebrates have been extensively studied. Some metabolic disturbances and histologic damages have been reported, as well as osmoregulation alterations. However, little work has been done about the effect of heavy metals on Na,K and Mg-ATPases of freshwater invertebrate gills. Na,K-ATPase is the prime mediator of ion trans…

The effectiveness of combination chemotherapy with cisplatinum and etoposide in the treatment of advanced non-small cell lung cancer.

1989

Twenty-one patients with histologically proven advanced or disseminated non-small cell lung cancer were treated with cisplatinum 80 mg/m2 i.v. day 1 and etoposide (VP16) 80 mg/m2 i.v. day 1- greater than 3.15 patients were evaluable for response. One patient (6.6%) achieved a complete response, 4 (26.7%) a partial response and 6 (40.0%) a stabilization of disease. Four patients (26.7%) progressed. An improvement in performance status was obtained in more than 50% of cases. Responders had a mean survival of 345 + days, while non-responders 191.7 days. The treatment was generally well tolerated. In our opinion this combination regimen offers good palliation for patients affected by advanced a…

Chemical sympathectomy and clorgyline-induced stimulation of rat pineal melatonin synthesis

1989

The response to administration of the specific monoamine oxidase A (MAO-A) blocker clorgyline was investigated in adult male Sprague-Dawley rats which were sympathectomized by injection of the false neurotransmitter 6-hydroxydopamine as newborns. In intact animals which served as controls, the contents of pineal indoles melatonin, serotonin, 5-hydroxytryptophan were augmented, and the content of 5-hydroxyindoleacetic acid decreased 90 min following clorgyline injections when compared to saline receiving rats. Sympathectomized animals exhibited similar responses but these were less pronounced. It is suggested that blocking of the oxidation of both MAO-A substrates, noradrenaline and serotoni…

Scattering from concentration fluctuations in polymer blends: A monte carlo investigation

1989

The collective scattering function Scoll( $$\vec q$$ ), which describes light (neutron-, x-ray) scattering under wavevector $$\vec q$$ , is obtained from Monte Carlo simulations for a symmetrical polymer mixture. The polymers are modelled by self-avoiding walks ofN A=NB=N steps on a simple cubic lattice, where a fractionφ V of sites is left vacant, and an attractive energye occurs if two neighboring sites are taken by the same kind of monomer. Spinodal curves are estimated from linear extrapolation of S coll −1 (0) vs.e/k B T, whereT is the temperature. Also the single chain structure factor is obtained and the de Gennes random phase approximation (RPA) can thus be tested. Unexpectedly, str…

Immune status towards Epstein-Barr virus in a group of Sicilian children.

1989

The prevalence of antibodies to Epstein-Barr virus-determined antigens was studied in 17 children with acute infectious mononucleosis (IM) and in 263 children hospitalized for diseases unrelated to EBV infection. Antibodies against Epstein-Barr viral capsid antigens (VCA) were observed in 173 patients of the control group (66%), but 58 of them (33,5%) had not yet developed antibodies against Epstein-Barr virus-associated nuclear antigen (EBNA). IgM-specific antibodies were not found in any of the children of the control group but were present in all of the 17 patients with IM. The rates of positivity for IgA anti-VCA and IgG anti-early antigen (EA) were similar in all age groups. Anti-viral…

A Boundary Control Approach to an Optimal Shape Design Problem

1989

Abstract We consider the problem of controlling the coincidence set in connection with an obstacle problem. We shall transform the obtained optimal shape design problem into a boundary control problem with Dirichlet boundary conditions.

Characterization of a proteinaceous extracellular coat synthesized by the ?slime? variant of Neurospora crassa

1989

Cells of the “slime” strain of Neurospora crassa synthesize a coherent extracellular material which remains attached to the cell surface, but is released into the liquid medium by shaking. The material was purified and studied by different criteria. By electron microscopy it appears as long wavy sheets which strongly bind concanavalin A, but not wheat germ agglutinin, and maintain their integrity in the absence of structural polysaccharides. Analysis of the purified material revealed that it was free of contaminating membranes; it contained more than 70% protein, 1% neutral sugars (glucose, mannose, fucose and galactose), less than 2% lipids and ca. 4% not-characterized hexosaminelike compo…

Titanium-aluminium catalysts with alkoxy ligands supported on aluminium oxide for ethylene polymerization

1989

Activity of a model titanium-aluminium catalyst system with n-BuO-ligands has been investigated in the polymerization of ethylene. The effect of the concentration of titanium compound on the support, the Al/Ti molar ratio, and catalyst concentration in the polymerization process on polyethylene yield has been determined. A mathematical optimation method has been used for the interpretation of results. The intervals of the optimum parameters of catalyst synthesis have been established, to obtain catalyst with a high activity in low-pressure ethylene polymerization. These specified optimum parameters have been applied in the subsequent synthesis of similar catalytic systems, differing in the …

Algebraic value of the electrooptic coefficients and nature of charge carriers in batio3single crystals

1989

Abstract Some monodomain pure and Fe doped barium titanate monocrystals are studied. The algebraic values of the electrooptic coefficients r 13 and r 33 are evaluated using an interferometric method. Then, from energy transfer results it is possible to conclude that majority carriers are positive charges in all the samples.

Some observations on the use of matrix modifiers in the determination of aluminum by electrothermal atomic absorption spectrophotometry

1989

Abstract Some evidence demonstrating that the use of matrix modifiers is necessary to obtain good calibration lines in the determination of aluminum by graphite furnace atomic absorption spectrophotometry is provided. It was found that the most sensitive results were obtained when Mg(NO 3 ) 2 was used instead of NH 4 H 2 PO 4 .

New neutron-rich isotopes of astatine and bismuth

1989

Neutron-rich isotopes of astatine have been produced through spallation reactions with 600 MeV protons on a232Th target and identified by spectroscopic techniques combined with one-line mass separation at the ISOLDE facility. The half-lives of218At and219At have been remeasured to be 1.5(3) s and 57(4) s, respectively. Four new isotopes of astatine,220−223At, have been observed for the first time, and their half-lives were found to be 3.73(13) min, 2.3(2) min, 54(10) s, and 50(7) s, respectively. Another nuclide,216Bi, has been observed for the first time as the daughter product of the220At alpha decay, and its half-life has been measured to be 6.6(21) min.

Volatile compounds produced by the ligninolytic fungus Phlebia radiata Fr. (Basidiomycetes) and influence of the strain specificity on the odorous pr…

1989

Abstract The odorous volatile compounds produced by 3 strains (out of 25 strains tested) of Phlebia radiata Fr. were investigated on six synthetic media and identified by GC-MS analysis. One of the 3 strains was odourless. Aromatic primary alcohols and a sesquiterpenic alcohol, α-bisabolol, were the most abundant metabolites for both of the other strains, which exhibited similar flavours and a similar gas chromatographic profile.

Partial purification and characterization of an NAD-dependent 3 beta-hydroxysteroid dehydrogenase from Clostridium innocuum

1989

In nine strains of Clostridium innocuum, 3 beta-hydroxysteroid-dehydrogenating activities were detected. 3 beta, 7 alpha, 12 alpha-Trihydroxy- and 3 beta-hydroxy-12-keto-5 beta-cholanoic acids were identified as reduction products of the respective 3-keto bile acids by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry. One strain was shown to contain a NAD-dependent 3 beta-hydroxysteroid dehydrogenase. Enzyme production was constitutive in the absence of added bile acids. The specific enzyme activity was significantly reduced by growth medium supplementation with 3-keto bile acids, with trisubstituted acids being more effective than disubstituted ones. A pH optimum o…

false

1989

Heat of crystallization significantly slows down polymer cooling and thus pressure drop increase during mould filling with thermoplastic crystalline polymers. If a correction of thermal diffusivity can account for such a cooling slow down at least as far as the effect on pressure drop is concerned, the use of nonisothermal crystallization kinetics may be avoided in the simulation of mould filling. A procedure to identify such a correction is outlined in this work. Pressure drop values during cavity filling calculated by using a corrected thermal diffusivity in the model proposed by Lord and Williams favourably compare with literature data taken with polypropylene and polyethylene resins. Be…

Abstracts from the CECAM workshop on computer simulations of cellular automata

1989

Causality and the Coulomb sum rule in nuclei.

1989

The spectral function in the Jost-Lehmann-Dyson representation of causal commutators is determined for the nonrelativistic limit of inclusive lepton scattering from nuclei. From this an extrapolation of the Coulomb sum rule to higher-momentum transfers is performed which is consistent with the requirement of causality.

A note on Taskinen's counterexamples on the problem of topologies of Grothendieck

1989

By the work of Taskinen (see [4, 5]), we know that there is a Fréchet space E such that Lb(E, l2) is not a (DF)-space. Moreover there is a Fréchet–Montel space F such that is not (DF). In this second example, the duality theorem of Buchwalter (cf. [2, §45.3]) can be applied to obtain that and hence is a (gDF)-space (cf. [1, Ch. 12 or 3, Ch. 8]). The (gDF)-spaces were introduced by several authors to extend the (DF)-spaces of Grothendieck and to provide an adequate frame to consider strict topologies.

Über einige Vertreter der Eryopoidea (Amphibia: Temnospondyli) aus dem europäischen Rotliegend (?höchstes Oberkarbon — Perm)2. Acanthostomatops

1989

Die larvalen bis fruhadulten Entwicklungsstadien desAcanthostomatops vorax aus dem sachsischen Rotliegend werden neu beschrieben. Einzelne Merkmale (z. B. Stapes und Teile des Postkranialskelettes) werden zum erstenmal dargestellt. Ein auf 25 Merkmalen basierendes Verwandtschaftsschema der Familie Zatrachydidae wird vorgestellt und diskutiert.

IN TEMA DI LAPAROSCHISI: Ricerche Sperimentali sull'Embrione di Pollo.

1989

Gli Autori descrivono la loro esperienza microchirurgica sull'embrione di pollo, utilizzato come modello sperimentale per verificare alcuni aspetti embriopatogenetici della laparoschisi.

Cytogenetic manifestations associated with the reversion, by gene amplification, at the HGPRT locus in V79 Chinese hamster cells.

1989

SummarySome HGPRT spontaneous revertants were isolated from a mutant line (E2) of V79 Chinese hamster cells and phenotypically characterized. Dot–Blot hybridization with a32P-Iabelled HGPRT probe revealed an increase in the number of HGPRT sequences in some of these revertants, suggesting the occurrence of gene amplification. Cytogenetic analysis performed in three of these revertants showed a characteristic abnormally banding region (ABR) on the elongated p arm of theXchromosome.In Situhybridization in one revertant (RHE2) showed that the amplified sequences reside on the p+arm of theXchromsome in two different localizations. Because of the very probable clonal origin of the revertant, the…

Monte Carlo study of surface critical behavior in the XY model.

1989

We have used Monte Carlo simulations to study the behavior of $L\ifmmode\times\else\texttimes\fi{}L\ifmmode\times\else\texttimes\fi{}D$ slabs containing classical spins which interact via nearest-neighbor $\mathrm{XY}$ coupling. The coupling constant ${J}_{S}$ for spins in the surface layer is fixed at $0.5J$. Finite-size scaling is used to analyze data for $D=59$ and to extract estimates for the surface critical exponents. We find that ${\ensuremath{\beta}}_{1}$ is in good agreement with theoretical predictions.

Die Politisierung der Biologie zur Zeit des Nationalsozialismus [1]

1989

Betrachtet man die in der Zeit zwischen 1933 und 1945 in Deutschland erschienene Literatur, die sich mit biologischen Inhalten oder der Definition des Faches Biologie auseinandersetzt, lassen sich zwei Pole der Biologie unterscheiden. Zum einen bleibt die Biologie, d. h. sowohl ihre Inhalte als auch ihre Vertreter, mehr oder weniger unbeeinflust vom Nationalsozialismus. Zum anderen wird die Biologie zum Werkzeug des Nationalsozialismus; ihre Aufgabe ist es dann, seine Ideologie mit biologischen Kenntnissen zu stutzen und zu bestatigen. Naturlich last sich nicht in jedem Fall eine klare Grenze zwischen diesen beiden Tendenzen ziehen. Oft werden an sich rein wissenschaftliche Erkenntnisse an …