Measurement of the ratio using event shape variables

1993

Abstract The branching fraction of Z → b b relative to all hadronic decays of the Z has been measured using event shape variables to preferentially select Z → b b events. The method chosen applies a combination of shape discriminators and the selection of high transverse momentum leptons to event hemispheres. From a sample of 440 000 hadronic Z decays collected with the ALEPH detector at LEP, the ration Γ b b Γ had = 0.228±0.005( stat. )±0.005( syst. ) is measured.

The heavenly spheres regained

1993

Remission of severe rheumatoid arthritis following liver transplantation.

1993

We present the case of a 32-year-old male who suffered from severe RA from the age of 21 years. After 9 years of active disease and poor response to therapy the patient developed severe hepatitis induced by the NSAID pirprofen. He went into fulminant hepatic failure necessitating emergency liver transplantation. Liver transplantation was followed by clinical and laboratory remission of his RA and he has remained virtually asymptomatic for more than 3.5 years. The possibility that this favourable clinical course was due to the immunosuppressive effect of the liver transplant rather than the ensuing immunosuppressive therapy is discussed.

Solar angle and sky light effects on ground reflectance measurements in a citrus canopy

1993

Abstract Ground radiometry was used to gather spectral data from different targets of a citrus canopy, in order to analyze the effect of solar zenith angle and proportion of diffuse radiation on spectral reflectance. Results have shown that the variation in solar angle causes significant changes in nadirsensed reflectance from vegetation, which exhibits a marked diurnal pattern with a minimum slightly shifted from the solar noon. This fact is more noticeable in the near-infrared and middle-infrared regions of the spectrum. Furthermore, the visible part of the spectrum has resulted in being highly influenced by the diffuse radiation incident on the canopy, which has been quantified by two di…

Molecular structure of the compound [Rh2(O2CCH3)3{(C6H4)P(BrC6H4-1,2)(C6H5)} · (HO2CCH3)2].Kinetic study of the exchange reaction of acetate groups w…

1993

Abstract The compound [Rh 2 (O 2 CCH 3 ) 3 {(C 6 H 4 )P(BrC 6 H 4 -1,2) (C 6 H 5 )} · (HO 2 CCH 3 ) 2 ] has been isolated in high yield from the thermal reaction of dirhodium tetraacetate and the phosphine P(BrC 6 H 4 -1,2) (C 6 H 5 ) 2 in acetic acid. The structure of this compound has been determined by X-ray diffraction; it crystallizes in the P 1 (triclinic) space group and contains three acetate groups bridging a Rh 2 4+ unit the RhRh distance being 2.432(1)A; the fourth bridging ligand is an ortho -bromophenyldiphenylphosphine metallated at one of the ortho positions of the unsubstituted phenyl rings. Two molecules of acetic acid occupy the axial coordination positions. Stepwise exch…

Electrolytic preparation of actinide filaments for laser resonance ionization spectroscopy

1993

Abstract For the determination of trace amounts of actinide elements by resonance ionization mass spectroscopy, atomic beams of these elements are produced by evaporation from rhenium substrates. The actinides are deposited by electrolysis as hydroxides in a 2 mm spot on a rhenium foil and covered electrolytically with a thin layer of rhenium or platinum. During heating of such a sandwich reduction occurs to the metallic state while diffusing through the overplated layers and the actinides are evaporated as atoms from the surface. With lead-doped platinum, efficient release is observed already at 1700°C in contrast to rhenium where 2100°C is required and a higher background is produced.

Correlation between clinical response and urinary interleukin levels using different doses and intravesical administration schedules of interferon-al…

1993

A total of 62 patients at high risk for recurrence of superficial bladder cancer were selected for a study designed to compare the prophylactic efficacy of different doses and schedules of sequential intravesical instillations of epirubicin and interferon-alpha-2b and to evaluate which sequence could enhance the release of cytokines in the urine. Our investigations showed a significant increase in urinary concentrations of interleukins in patients who received the sequential intravesical administration of epirubicin and interferon-alpha-2b. Higher urinary concentrations of interleukins and a lower recurrence rate were detected in patients who received interferon-alpha-2b 24 h after epirubic…

Selective bilateral blood sampling from the inferior petrosal sinus in Cushing's disease: effects of corticotropin-releasing factor and thyrotropin-r…

1993

We sought to enhance the sensitivity of selective bilateral blood sampling to determine adrenocorticotropin (ACTH) and prolactin levels in the inferior petrosal sinus (IPS) by administering two stimulatory agents--corticotropin-releasing factor (CRF) and thyrotropin-releasing hormone (TRH). We then determined the ACTH and prolactin levels in the IPS of 10 patients with Cushing's disease. After peripheral administration of both CRF and TRH, ACTH levels were significantly higher on the tumor side in all patients. The prolactin level was significantly higher on the tumor side when CRF or TRH was used to stimulate pituitary secretion. Postsurgical immunohistochemistry studies revealed productio…

Ni(II) and Zn(II) complexes with cinoxacin. Synthesis and characterization of M(Cx)2(DMSO)n(H2O)m (n=0, 2; m=2, 4). Crystal structures of [M(Cx)2(DMS…

1993

Abstract New metal complexes of cinoxacin (HCx=1-ethyl-l,4-dihydro-4-oxo(1,3)dioxolo(4,5-g)cinnoline-3-carboxylic acid) were synthesized, isolated as [Zn(Cx)2(DMSO)2]·4H2O, [Ni(Cx)2(DMSO)2]·4H2O, Zn(Cx)2·4H20 and Ni(Cx)2·2H2O, and characterized by elemental analysis, TG studies, IR and UVVis spectroscopic techniques. The crystal and molecular structures of the complexes [M(Cx)2(DMSO)2]·4H2O (M=Zn(II), Ni(II)) have been determined by X-ray structure analysis. The crystals of [Zn(Cx)2(DMSO)2]·4H2O are triclinic, space group P 1 with unit cell dimensions a=8.950(4), b=9.168(5), c=11.650(6) A, α=69.06(1), β=82.05(1), γ=75.63(1)°, V=863.6(8) A3; [Ni(Cx)2(DMSO)2]·4H20 is monoclinic, space group …

A study of spalling behaviour of PAN fibre-reinforced concrete by thermal analysis

1993

Comparisons are made between polypropylene (PP) fibres and polyacrylonitrile (PAN) fibres in order to relate the thermal properties of fibres with the respective fibre mortar behaviour under thermal exposure. Thermogravimetry (TG), differential scanning calorimetry (DSC) and thermochromatography (ThGC) are utilized. When a cementitious fibre mortar is being heated, several physical phenomena occur in the temperature range between 100°C and 200°C. There is a significant difference in the thermal behaviour between PP and PAN fibres. PP fibres melt at 160–170°C. The non‐melting behaviour of PAN fibre together with its rapid exothermic degradation reactions at around 300°C may add risk to the s…

Determination of the composition of isomeric mixtures of allylstannanes by means of 119Sn and 13C NMR measurements

1993

Abstract Allylstannanes of the type Bun3Sn(C3H3) ((C3H3 = allenyl and propargyl) Me3Sn(C4H7), Bun3Sn(C4H7), Ph3Sn(C4H7), Me3Sn(C4H7)2 and Bun3Sn(C4H7)2 [C4H7 = (E)-but-2-enyl, (Z-but-2-enyl, and but-1-en-3-yl] were prepared via Grignard reactions as isomeric mixtures whose compositions can be directly determined by 119Sn and 13C NMR spectrometry. The 119Sn and 13C δ-values of all possible isomers together with the isomeric compositions of freshly prepared compounds and after isomerization in dry methanol under reflux are reported. The course of isomerization of some compounds in anhydrous methanol at room temperature or in the presence of Bu3SnCl was followed by 119Sn NMR spectrometry.

Environmental assessment in Latvia: Overview of past research and future perspectives

1993

Diagnosis of papillary muscle rupture after acute myocardial infarction by transthoracic and transesophageal echocardiography.

1993

The sensitivity of transthoracic echocardiography to visualize the structural abnormality of papillary muscle rupture (PMR) after acute myocardial infarction can be anticipated to average about 50%; therefore, we evaluated five patients exhibiting the condition with both transthoracic and transesophageal echocardiography. The use of the two imaging techniques resulted in the fact that no instance of PMR was missed. Using transthoracic echocardiography in two patients and transesophageal echocardiography in four, the ruptured papillary muscle was visualized directly. Mitral insufficiency as an indirect sign was observed in all patients. In one patient the papillary muscle rupture developed i…

A precise measurement of ΓZ→bb/ΓZ→hadrons

1993

A measurement of the partial width ratio Γbb/Γhad using a method which tags the Z --> bb decays through the lif etime of the produced heavy hadrons is presented. This method relies on the tracking precision afforded by a double-sided silicon vertex detector. The tag algorithm makes a probabilistic interpretation of three-dimensional track impact parameters, using the data to measure the resolution. By tagging the two b hadrons separately, both Γbb/Γhad and the tag efficiency can be determined from the data. For a 26% efficiency of tagging a single b hadron within the vertex detector solid angle coverage, a purity of 96% is achieved. A value of Γbb/Γhad = 0.2192+/-0.0026(stat.)+/-0.0016(Γcc/…

$$N\bar N$$ annihilation at rest into five pions

1993

\(N\bar N\) annihilation at rest into five pions was studied in the ASTERIX spectrometer by stopping antiprotrons from LEAR in a H2 or D2 gas target. In\(\bar pp\) annihilations in H2 leading to the π+π−π+π−π0 final state, the invariant mass spectra of two, three, and four pions show no evidence for any new narrow states. In\(\bar pn \to \pi ^ + \pi ^ - \pi ^ + \pi ^ - \pi ^ - \) the difference of the four pion mass spectra recoiling against a π− and those recoiling against a π+ shows a resonance-like structure (“ζ (1480)”), confirming a previous analysis with a smaller event sample. The ζ (1480) mass is shown to depend strongly on the momentum of the spectator proton. In H2, we searched fo…

Soot particle properties in the microwave range

1993

This paper outlines the study of Diesel soot particle properties in the frequency band 2.0-40.0 GHz. Using a transmission/reflection as well as a cavity perturbation method, the complex dielectric constant ?* = ?1 - j?2 was measured for multiple of samples (soot particles produced in a Diesel engine and deposited on paper filter). From the analysis of the experimental data the following conclusions appear: The complex dielectric constant - i.e. the HF electrical conductivity and the microwave power absorption efficiency - are dependent on the frequency and the soot particle thickness. Increasing the soot particle thickness causes the reflection to be stronger and results in less influence o…

SEMICLASSICAL DESCRIPTION OF SPIN EXCITATIONS OF THE PARTICLE-CORE INTERACTION SYSTEM

1993

A model Hamiltonian describing a nucleon moving in a shifted oscillator well and inter-acting with a harmonic core through a quadrupole-quadrupole term is semiclassically treated. The solutions of the linearised equations of motion are quantised by the Bohr-Sommerfeld procedure. Among the four RPA modes, there is one which corresponds to the harmonic vibration of the spin degree of freedom. This mode is analogous to the spin wave mode describing a system of interacting spins placed in a magnetic field. The state describes a harmonic wobbling motion around a stationary state belonging to the ground rotational band.

Synthesis and electrochemical study of a new doubly-metallated compound with the ferrocene-labelled phosphine PPh2(C5H4)Fe(C5H5)

1993

Abstract Direct reaction of the metalled compound Rh 2 (μ 2 -O 2 CCH 3 ) 3 [μ 2 -(C 6 H 4 ) PPh 2 ]·(H 2 O) 2 with PPh 2 Fc [Fc = (C 5 H 4 )Fe(C 5 H 5 )] in chloroform solution yields the corresponding mono-adduct Rh 2 (O 2 CCH 3 ) 3 [(C 6 H 4 )PPh 2 ]·(PPh 2 Fc) ( 1 ), which has been characterized by 31 P NMR spectroscopy. Photochemical irradiation of 1 in chloroform gives the compound Rh 2 (μ-O 2 CCH 3 ) 2 (η 2 -O 2 CCH 3 )[μ 2 -(C 6 H 4 )PPh 2 ][PPh 2 Fc]·(H 2 O) ( 2 ) in practically quantitative yield. Compound 2 , by thermal treatment in chloroform solution, yields cleanly the doubly-metallated compound Rh 2 (μ 2 -O 2 CCH 3 ) 2 [μ 2 -(C 6 H 4 )PPhFc][μ 2 -(C 6 H 4 )PPh 2 ]·(H 2 O) 2 ( …

Magnetic resonance imaging in juvenile Canavan disease

1993

We present a 2-year-old boy and a 6-year-old girl with mild Canavan disease (CD). Aspartoacylase activity in skin fibroblasts was deficient. Magnetic resonance imaging (MRI) of the brain did not show the prominent leucodystrophy previously reported in CD, but there was a hyperintense signal from the lentiform nuclei and the heads of the caudate nuclei on the T2-weighted MR images. This suggests a specific vulnerability of the corpus striatum in these patients. In the older patient, the white matter became affected at the age of 6 years. Proton magnetic resonance spectroscopy (1H-MRS) of white matter revealed a normal concentration of N-acetyl-L-aspartate (NAA) and a markedly decreased conce…

Influence of blood sampling from venipunctures and catheter systems on serial determinations of prothrombin activation fragment 1 + 2 and thrombin-an…

1993

To evaluate the influence of different blood sampling techniques on test results of thrombin-antithrombin III complex (TAT) and prothrombin fragment 1 + 2 (F1 + 2) serial determinations were performed. In six groups of nonrandomized patients (ten patients each) the concentrations of the coagulation markers of blood samples from central catheters (internal jugular, caval, Shaldon, pulmonary artery) and peripheral cannulas (17G and 18G) were compared with those of blood samples obtained simultaneously from direct venipunctures of the contralateral arm. Medians and 25th-75th percentiles of TAT and F1 + 2 concentrations of plasmas obtained from central catheters were not different from those ta…

A pilot study demonstrating how inhaled furosemide enhances the bronchodilator effect of salbutamol

1993

Abstract To investigate whether inhaled furosemide can improve the bronchodilator effect of salbutamol, a single-blind crossover study in 10 subjects with stable asthma was designed. Each subject inhaled two puffs of salbutamol (200 μg) 1 hour after premedication with an aerosol preparation of either furosemide or placebo. Forced expiratory volume in 1 second (FEV 1 ) was measured before premedication, again before inhalation of salbutamol, and again 30, 60, and 90 minutes after, and 2, 3, 4, and 5 hours after inhalation of salbutamol. The FEV 1 at each time interval was greater on furosemide days but the difference was significant at 1, 4, and 5 hours after salbutamol inhalation. The areas…

On the Retention of Diuretics in Micellar Liquid Chromatography and Their Site of Action Within the Nephron

1993

Abstract The therapeutical action of diuretics has been attributed to their hydrophobic character, among other properties. Therapeutical and physiological classifications of diuretics are correlated. The site of action of high efficacay diuretics is the loop of Henle, that of intermediate efficacy diuretics is the distal tubule and that of low efficacy diuretics is the proximal and distal tubules, and the collecting duct. Partition coefficients between water and micelles offer a scale for hydrophobicity, which leads to a further correlation between retention in Micellar Liquid Chromatography (MLC), with a sodium dodecyl sulphate mobile phase and an ODS-C18 column, and the sites of action wi…

Oculovestibular interactions under microgravity.

1993

On a space mission in March 1992 a set of experiments were performed aimed at clarifying the interaction between visual, proprioceptive and vestibular inputs to the equilibrium system. Using the VESTA goggle facility from the European Space Agency we investigated the effect of pure neck receptor stimulation on eye position as measured by the flash afterimage method and on perception of a head-fixed luminous line in space. Space vestibular adaptation processes were measured by rotating pattern perception during prescribed head movements. It was found that static ocular counterrotation does not occur under micro gravity conditions. This result suggests that the neck receptors apparently do no…

Nomenclature et régulation médicalisée en médecine ambulatoire

1993

La récente négociation d'une nouvelle convention médicale pour la médecine libérale ne s'est pas effectuée sans difficulté. Le compromis qui a permis la signature de cette convention a retenu le principe d'une responsabilisation des médecins à travers un projet de maîtrise médicalisée. Ce projet conduit à réformer la nomenclature des actes en vigueur depuis 1972 et à définir de nouveaux référentiels de l'activité médicale qui serviraient de base à l'évaluation et à la maîtrise de cette activité. Toutefois; les objectifs d'un nouveau codage des actes ne sont pas clairement définis et l'efficacité d'une telle politique pour réduire les dépenses est loin d'être garantie.En effet, la réforme de…

Die Behandlung akuter gastrointestinaler Schmerzen

1993

Ein wichtiges und das haufigste Leitsymptom akuter gastrointestinaler Erkrankungen ist der Bauchschmerz, der vor dem Hintergrund der Lokalisation, assoziierter Symptome und durch die korperliche Untersuchung zu erhebender Befunde entscheidende diagnostische Impulse zu geben vermag. Als symptomatisches Therapiekonzept spricht die Schmerzbehandlung bei akuten gastrointestinalen Erkrankungen, beispielsweise dem akuten Abdomen, der akuten Pankreatitis, der Gallenkolik, dem Ulcus pepticum und der Divertikulitis eine wesentliche Rolle. Zur Schmerztherapie des peptischen Ulkus haben sich der H+-, K+-ATPase-Inhibitor Omeprazol und H2-Rezeptoren-Blocker als rasch wirksam und effektiv erwiesen. Wahre…

Calling behaviour of female Periplaneta americana: Behavioural analysis and identification of the pheromone source

1993

Abstract The site for the production of Periplanone B, one of the components of the female sex pheromone of Periplaneta americana , was localized in glands situated in the genital atrium, and we have called these structures atrial glands. While emitting the sex pheromone, females adopt a characteristic calling posture during which time the atrial glands are exposed. Behavioural assays of males utilizing pentane extracts of various female body parts revealed that atrial gland extracts are highly attractive, and induced more wing-raising behaviour, than any other female body part. GC-MS analyses support these results by revealing that Periplanone B is only present in the atrial glands. We est…

Eingeladener Kommentar: Der zerebelläre Infarkt-Klinik, Bildgebung und Indikation zur neurochirurgischen Intervention

1993

186 Early Defibrillation in a Two-Tier Emergency Medical System (EMS) with Physician Staffed Ambulances

1993

Der Sicherheitsgurt: Auswirkungen auf das Verletzungsmuster von Autoinsassen

1993

Since 1984 the law concerning safety belts has been implemented; this paper deals with the findings in 386 victims of motor accidents who were x-rayed between 1981 and 1989. Minor injuries have been ignored. The number of passengers wearing belts increased by 30% after 1984. The number of passenger injuries did not decrease. Injuries directly caused by the belts included a small number of fractures of clavicles, the sternum and ribs and one pelvic fracture, one serious abdominal injury with tearing of the mesenteric artery and one ruptured spleen. An indirect result of wearing seat belts was a marked increase in cervical whiplash injuries and some increase in thoracic vertebral fractures. N…

New tubular transition metal oxoanionic derivatives: a systematic approach to condensed phases of the dumortierite family

1993

Abstract An unified synthetic approach has allowed us to isolate a wide set of highly condensed oxoanionic derivatives of transition metals by using solution chemistry procedures. New phases are described [Ni 12+ x H 6−2 x (AsO 4 ) 8 (OH) 6 . Ni 6 (SeO 3 ) 4 (OH) 4 ], and the preparation of other already known [Ni 12+ x H 6−2 x (PO 4 ) 8 (OH) 6 , Ni 3 Te 2 O 6 (OH) 2 ] is significantly simplifi ed. The structure of these derivatives, as well as that of other phases such as M 11 (HPO 3 ) 8 (OH) 6 (M=Zn, Co, Ni), previously characterized by us, can be related to that of the dumortierite mineral. The main features of the tubular channels that characterize this structure and the possibility to …

Photoaffinity labeling of Torpedo acetylcholine receptor by physostigmine.

1993

The plant alkaloid physostigmine, an established anti-cholinesterase agent of the carbamate type, has recently been shown to bind to the nicotinic acetylcholine receptor from Torpedo marmorata electrocytes [Okonjo, K. O., Kuhlmann, J.Maelicke, A. (1991) Eur. J. Biochem. 200, 671-677]. Pharmacological studies of physostigmine-induced ion flux into nicotinic-acetylcholine-receptor-rich membrane vesicles, indicated distinct binding sites for physostigmine and acetylcholine. As shown in this study by photoaffinity labeling with [phenyl-(n)-3H](-)physostigmine, the physostigmine-binding site is located within the same subunit (alpha polypeptide) of the receptor as the acetylcholine-binding site.…

Spatial multifractal properties of wave packets in the Anderson model of localization.

1993

The multifractal properties of electronic wave functions in disordered samples are investigated. In a given energy range all eigenstates are determined for the same disorder configuration in the Anderson model of localization. It is shown that the singularity spectrum and the generalized dimensions change only slowly with energy, aside from statistical fluctuations. More important, the wave packet constructed by linear combination of the eigenstates shows quantitatively the same multifractal properties. Consequences for the transport properties of electronic states in disordered systems are discussed.

Experimental ground stateg J-factor of Ba+ in a Penning ion trap

1993

We observed the Zeeman-splitting of the 6S1/2 – 6P1/2 resonance transition of Ba+-ions (493.4 nm) in a 6T magnetic field. The ions were stored in a Penning quadrupole trap. We polarized the ground state by optical pumping and in a microwave-optical double resonance experiment we measured the ground state Zeeman-splitting. From the resonance frequency and the cyclotron frequency of electrons stored in the same trap we derived theg-factor of the 6S1/2 state. The result isgJ(6S1/2)=2.002 490 6(11), in reasonable agreement with recent calculations.

Morbidity and mortality in Estonia, Latvia and Lithuania in the 1980's.

1993

The purpose of the present study was to examine the general morbidity and mortality rates in the three Baltic republics — Estonia, Latvia and Lithuania during a decade before the collapse of the Soviet Union. Official statistical data were used to compare morbidity and mortality rates. A method of standardization and life table functions were employed. Soviet morbidity statistics were predominantly descriptive, and based mainly on crude rates registered cases of illness during a year per 100 000 population. The death rates during the Soviet period are a better indicator of the health of the populations than more specific health indicators. A general deterioration of the ecological, social …

Supergaussian beams of continuous order as GRIN modes

1993

Abstract It is recognized that for certain planar waveguides, and for certain cylindrical GRIN fibers, some diffraction modes are supergaussian beams of continuous order.

Effect of irradiation temperature and dose rate on the mechanical tensile behaviour of low density polyethylene

1993

Abstract The effect of ageing due to gamma radiation, at various dose rates and temperatures, on the mechanical tensile behaviour of low density polyethylene is studied. In order to detect synergistic effects, tensile tests on samples subjected to thermal treatment corresponding to the same temperature for the same time as for the irradiation tests have also been performed. The results indicate a generalized decrease of the elongation at break, with brittleness of the material for the most severe ageing treatments. For modulus values, an increase is observed for particular experimental conditions. These results are related to morphological and structural modifications induced in the polymer…