4-Manifold topology I: Subexponential groups

1995

The technical lemma underlying the 5-dimensional topological s-cobordism conjecture and the 4-dimensional topological surgery conjecture is a purely smooth category statement about locating ~-null immersions of disks. These conjectures are theorems precisely for those fundamental groups ("good groups") where the ~l-null disk lemma (NDL) holds. We expand the class of known good groups to all groups of subexponential growth and those that can be formed from these by a finite number of application of two opera- tions: (1) extension and (2) direct limit. The finitely generated groups in this class are amenable and no amenable group is known to lie outside this class.

4-Manifold topology II: Dwyer's filtration and surgery kernels

1995

Even when the fundamental group is intractable (i.e. not "good") many interesting 4-dimensional surgery problems have topological solutions. We unify and extend the known examples and show how they compare to the (presumed) counterexamples by reference to Dwyer's filtration on second homology. The development brings together many basic results on the nilpotent theory of links. As a special case, a class of links only slightly smaller than "homotopically trivial links" is shown to have (free) slices on their Whitehead doubles.

Detection of primary DNA damage: applicability to biomonitoring of genotoxic occupational exposure and in clinical therapy

1995

The biological effect of putative genotoxic chemicals in the work place environment was monitored in peripheral mononuclear blood cells of exposed workers. DNA strand breaks, alkali-labile sites of DNA and DNA cross-links were measured using the alkaline filter elution method. A dose dependent increase in DNA damage was found in sterilization workers exposed to ethylene oxide and metal workers with exposure towards N-nitrosodiethanolamine. Two subpopulations with different response to the external exposure were found in nonsmoking sterilization workers. Nurses handling antineo-plastic agents without adequate safety provisions showed a statistically significantly higher rate of DNA strand br…

Treatment of recurrent and/or metastatic squamous cell head and neck carcinoma with a combination of vinorelbine, cisplatin, and 5-fluorouracil: a mu…

1995

Summary Purpose Vinorelbine has been demonstrated to be active against squamous cell carcinomas of the headneck (SCHNC) and lung. This multicenter phase II trial was carried out to evaluate the activity and tolerability of the combination of vinorelbine, cisplatin, and 5-fluorouracil given on an outpatient schedule in a series of 80 patients with recurrent SCHNC. Patients and methods Eighty patients with recurrent and/ or metastatic SCHNC were treated with a combination of CDDP 80 mg/m2 on day 1, 5-FU 600 mg/m2 as a 4-hour infusion on days 2-5, and vinorelbine 25 mg/m2 on days 2 + 8. This cycle was repeated every 28 days. Most patients had oral cavity, larynx, or oropharynx carcinoma (88%).…

Preparation, crystal structure, and infrared characterization of the first thiocyanato-oxy-antimonate(III) [(CH3)4N]2[Sb6O4(NCS)12]

1995

The salt [(CH3)4N]2[Sb6O4(NCS)12] is the first identified thiocyanato-oxy-antimonate(III) complex. Reported are details of the synthesis, relevant infrared data and its x-ray structure. The compound crystallizes in the triclinic space group P1 with Z = 2 (C10H12N7O2S6Sb3) and unit cell dimensions a = 11.314(6), b = 12.846(3), c = 8.679(2) A; α = 91.93(3)°, β = 90.31(3)° and γ = 99.13(3)°. It contains centrosymmetric [Sb6O4(NCS)12]2− anions packed with isolated tetramethyl-ammonium cations. The fundamental structural element of the anion is provided by the fusion of three SbOSbO rings forming a zig-zag portion of a ribbon, only slightly pleated. Peculiar is the unequivalence of the six thioc…

Ordering and demixing transitions in multicomponent Widom-Rowlinson models.

1995

We use Monte Carlo techniques and analytical methods to study the phase diagram of multicomponent Widom-Rowlinson models on a square lattice: there are M species all with the same fugacity z and a nearest neighbor hard core exclusion between unlike particles. Simulations show that for M between two and six there is a direct transition from the gas phase at z < z_d (M) to a demixed phase consisting mostly of one species at z > z_d (M) while for M \geq 7 there is an intermediate ``crystal phase'' for z lying between z_c(M) and z_d(M). In this phase, which is driven by entropy, particles, independent of species, preferentially occupy one of the sublattices, i.e. spatial symmetry but not …

Procedural learning and prefrontal cortex.

1995

A method for determining the position and size of optimal sequence regions for phylogenetic analysis.

1995

The availability of fast and accurate sequencing procedures along with the use of PCR has led to a proliferation of studies of variability at the molecular level in populations. Nevertheless, it is often impractical to examine long genomic stretches and a large number of individuals at the same time. In order to optimize this kind of study, we suggest a heuristic procedure for detection of the shortest region whose informational content can be considered sufficient for significant phylogenetic reconstruction. The method is based on the comparison of the pairwise genetic distances obtained from a set of sequences of reference to those obtained for different windows of variable size and posit…

Electron-gas clusters: the ultimate jellium model

1995

The local spin-density approximation is used to calculate ground- and isomeric-state geometries of jellium clusters with 2 to 22 electrons. The positive background charge of the model is completely deformable, both in shape and in density. The model has no input parameters. The resulting shapes of the clusters exhibit breaking of axial and inversion symmetries; in general the shapes are far from ellipsoidal. Those clusters which lack inversion symmetry are extremely soft against odd-multipole deformations. Some clusters can be interpreted as molecules built from magic clusters. The deformation produces a gap at the Fermi level. This results in a regular odd-even staggering of the total ener…

Does plasma endothelin during thrombolysis depend on infarct size? A pilot study

1995

Dear Sir, Endothelin is a recently discovered endotheliumderived vasoconstrictive peptide [1]. Endothelin's actions are altered in various models of cardiac injury [2]. Furthermore, it has been shown that endothelin is increased during reperfusion [2]. Studies have shown a significant increase in endothelin-1 (ET-1) in the early phases of acute myocardial infarction (AMI) and percutaneous transluminal coronary angioplasty (PTCA) [3-8]. In addition, a significant inverse relation between ventricular function and plasma ET-1 has been shown [6]. These data suggest that ET-1 may provide a marker of endothelial injury in the early phases of coronary ischemia or may even contribute to alterations…

Energy relaxation in a? 4 with long range interactions

1995

We investigate the influence of long range interactions on the relaxation behaviour of a lattice model with an on-site potential ofϕ 4-type and “infinite” range harmonic interactions. For finite number of particlesN, it is shown that the autocorrelation functions of the fluctuations of the one-particle energiesE n(t) decays exponentially. The corresponding relaxation time τ is proportional toN and is given by τ(T, N) =Nτ0(T). The temperature dependent time scale τ0 can explicitly be related to the dynamics of a one-particle correlator of the noninteracting system. The results are derived using Mori-Zwanzig projection formalism. The corresponding memory kernel is calculated within a mode cou…

Doppler free ?dark resonances? for hyperfine measurements and isotope shifts in Ca+ isotopes in a Paul trap

1995

We have observed “dark resonances” in theA-type level structure, formed by the 4S1/2 ground state, the 4P1/2 excited state and the low lying metastable 3D3/2 state in the Calcium ion, confined in a Paul radio-frequency trap. These Doppler-free and potentially very narrow resonances were used to determine the magnetic dipole hyperfine interaction constant A for the 4P1/2 and 3D3/2 state of43Ca+, giving −142(8) MHz and −48.3(1.6) MHz, respectively. From measurements of the P-D (E1) and S-D (E2) transition wavelength in a mixture of43Ca+ and40Ca+ we determined the isotope shifts of these lines.

Adiciones a la flora alicantina

1995

RESUMEN: Se dan a conocer algunas de las ultimas novedades de plantas encontradas en la provincia de Alicante, siendo muchas de ellas primera cita para este territorio. Biarum dispar (Schott) Talavera, Spergularia tangerina P. Monnier, Verbascum dentifolium Delile, Coleostephus myconis (L.) Reichenb. fil., Ononis laxiflora Desf., Vicia narbonensis L., Anthemis altissima L., destacan por su originalidad y rareza en la mitad oriental de la Peninsula Iberica.

Genome size and chromosomes in marine sponges [Suberites domuncula, Geodia cydonium]

1995

The genome size of the marine sponges Suberites domuncula and Geodia cydonium has been determined by flow cytofluorometric analysis using diamidino-phenylindole [DAPI]. Using human lymphocytes as reference the amount of DNA in cells from S. domuncula has been determined to be 3.7 pg and that of G. cydonium 3.3 pg. While no chromosomes could be identified in G. cydonium, the karyotype of the Suberites domuncula is 32 chromosomes in the diploid state. The size of the chromosomes was between 0.25 and 1.0 micron. No pronounced banding pattern was visible.

Expansion of SN 1993J

1995

A sequence of images from very long baseline interferometry shows that the young radio supernova SN 1993J is expanding with circular symmetry. However, the circularly symmetric images show emission asymmetries. A scenario in which freely expanding supernova ejecta shock mostly isotropic circumstellar material is strongly favored. The sequence of images constitutes the first “movie” of a radio supernova.

QCD effects andb-tagging at LEP I

1995

We analyze the impact of usingb-tagged samples in studying non-Abelian effects due to QCD ine + e − → 4jet events at √s=M z 0, using angular variable analyses and comparisons withe + e − → 3jetγ events. We find that QCD effects are largely enhanced inb-quark samples with respect to ‘unflavoured’ ones, where energy-ordering is used to distinguish between gluon and quark jets. We show that theb-quark mass influences the angular distributions significantly and should not be neglected.

Insulin-dependent diabetes mellitus and glycosaminoglycans.

1995

The influence of diabetic nephropathy on urinary glycosaminoglycan distribution was assessed in 96 patients with insulin-dependent diabetes mellitus (IDDM, 49 female, age: 16 - 64 yrs, median 35; duration of IDDM: 0 - 43 yrs, median 13 yrs) in comparison to 103 healthy controls (57 female, 17 - 82 yrs, median 40 yrs). Glycosaminoglycan concentration of 24 h urine samples was determined by means of precipitation with cethylpyridinium chloride and potassium acetate in ethanol followed by a colorimetric test with carbazole. A marked difference (p = 0.0008) in urinary glycosaminoglycan excretion between patients (19.0, 12.4, 35.6 mg/24 h, median, 25th, 75th percentile) and controls (15.8, 10.4,…

Enhanced diffraction of light in GaAs microcavities

1995

We theoretically analyze the diffraction of light by gratings that are photogenerated in Fabry–Perot microcavities. The coupled-wave theory of volume gratings is combined with appropriate boundary conditions to yield expressions for the diffraction efficiency. Multiple round trips within the cavity are seen to increase the effective grating thickness and therefore the efficiency. Numerical calculations specific to GaAs microcavities show that the diffraction efficiency can be enhanced by more than 2 orders of magnitude at the resonant wavelengths.

Remark on linear forms

1995

Dizziness and vertigo in a department of emergency medicine.

1995

Dizziness is a common and vexing diagnostic problem in emergency departments. The term is rather undefinite and often misused, but can in practice be classified into four categories: fainting, disequilibrium, vertigo and miscellaneous syndromes. Vertigo is the most common category of dizziness. Classification of vertigo can be based either on chronological criteria (acute, recurrent or chronic vertigo) or on topographical criteria (peripheral or central vertigo). Physicians working in emergency departments must be able to rapidly identify patients with potentially serious forms of vertigo, which could cause death or disability, and patients with mild conditions, that can be effectively trea…

First International Merkel Cell Symposium, Heidelberg, Germany

1995

Interaction of 68–kDa TAR RNA-binding protein and other cellular proteins with rpion protein-RNA stem-loop

1995

The RNA stem-loop structure of the trans-activating region TAR sequence of human immunodeficiency virus-1 mRNA is the binding site for a number of host cell proteins. A virtually identical set of proteins from HeLa nuclear extracts was found to bind to the predicted RNA hairpin element of prion protein (PrP) mRNA, as demonstrated in UV cross-linking/RNase protection and Northwestern assays. We show that the cellular TAR loop-binding protein, p68, is among those proteins which associate with PrP RNA. Competition experiments with various TAR RNA mutants revealed that binding of partially purified p68 to PrP RNA stem-loop occurs sequence-specifically. The 100-kDa 2-5A synthetase which is invol…

Measurement ofD s + meson production inZ decays and of theB s 0 lifetime

1995

D + mesons produced inZ 0→bb events were separated from theZ 0→cc component using a lifetime tag. Using a sample of 1.5 million hadronicZ decays collected with theAleph detector theB 0 andD s + yields have been measured: $$\begin{gathered} \hfill B(b \to \bar B_s^0 )B(\bar B_s^0 \to D_s^ + ) = 0.088 \pm 0.020(stat.) \\ \hfill \pm 0.020(stat.) \\ \hfill B(c \to D_s^ + ) = 0.088 \pm 0.020(stat.)_{ - 0.016}^{ + 0.019} (syst.) \\ \end{gathered} $$ TheB 0 lifetime was measured in aB 0 enriched sample reconstructing the decay length from the vertex of theD + with a hadron from theB 0 decay. The result obtained is: $$\tau _{B_s } = 1.61_{ - 0.29}^{ + 0.30} (stat.)_{ - 0.016}^{ + 0.018} (syst.)$$ p…

The experimental observation of the potential barrier for self-trapped exciton decay into F-H pair in KCl-Na crystals

1995

Abstract The optical absorption induced by the electron pulse irradiation of Na+ doped KCl has been measured. Transient optical absorption band of FA centers was observed at 80 K (LNT). The temperature dependence of FA center formation was studied. It is proposed that the obtained activation energy originates from the potential barrier between the STE perturbed by the cation impurity and the nearest neighbour FA-H pair. The mechanism of the suppression of the defect formation by the monovalent cation impurity in alkali halide crystals is discussed.

A model for long-term potentiation and depression

1995

A computational model of long-term potentiation (LTP) and long-term depression (LTD) in the hippocampus is presented. The model assumes the existence of retrograde signals, is in good agreement with several experimental data on LTP, LTD, and their pharmacological manipulations, and shows how a simple kinetic scheme can capture the essential characteristics of the processes involved in LTP and LTD. We propose that LTP and LTD could be two different but conceptually similar processes, induced by the same class of retrograde signals, and maintained by two distinct mechanisms. An interpretation of a number of experiments in terms of the molecular processes involved in LTP and LTD induction and …

An electrochemical quartz crystal microbalance study of lithium insertion into thin films of tungsten trioxide II. Experimental results and compariso…

1995

Abstract Lithium insertion into amorphous thin films of tungsten trioxide (a-WO 3 ) prepared by thermal vacuum evaporation of WO 3 powder has been studied experimentally by chronoamperometry, cyclic voltammetry and ac impedance spectroscopy associated with electrochemical quartz crystal microbalance (EQCM). During cathodic polarization of the electrode and at short times two antagonistic processes occur. One is a non faradaic process and is associated with the expulsion of anions from the electrode surface under the effect of the electric field built in the electrolyte when a potential difference is imposed between the electrodes. The other one is the faradaic insertion of non-solvated lith…

Prevalence of myxomatous mitral valve prolapse in patients with lymphocytic thyroiditis

1995

Abstract In conclusion, given the cardiac (mitral regurgitation, endocarditis, thromboembolic complications, arrhythmic sudden death) and neurologic (cerebral embolic event) complications of the pathologic forms of MVP, 6,8 physicians should look carefully for myxomatous involvement of the mitral valve and prolapse in patients with autoimmune thyroid diseases. Patients should be monitored and prophylactic antibiotic treatment recommended when appropriate.

alpha-Bungarotoxin, kappa-bungarotoxin, alpha-cobratoxin and erabutoxin-b do not affect [3H]acetylcholine release from the rat isolated left hemidiap…

1995

Endplate preparations of the rat left hemidiaphragm were incubated with [3H]choline to label neuronal transmitter stores. Nerve evoked release of newly-synthesized [3H]acetylcholine was measured in the absence of cholinesterase inhibitors to investigate whether snake venom neurotoxins by blocking presynaptic nicotinic autoreceptors affect evoked transmitter release. Contractions of the indirectly stimulated hemidiaphragm were recorded to characterize the blocking effect of alpha-neurotoxins at the post-synaptic nicotinic receptors. Neither the long chain neurotoxins alpha-cobratoxin (1 microgram ml-1) and alpha-bungarotoxin (5 microgram ml-1) nor the short chain neurotoxin erabutoxin-b (0.1…

Depressive symptoms in late life : Results from a study in three Nordic urban localities.

1995

The prevalence and correlates of depressive symptoms among 75-year-olds were examined in three Nordic urban localities: Gothenburg, Sweden (n=446), Jyvaskyla, Finland (n=382) and Glostrup, Denmark (n=541). Depressive symptomatology was assessed with the Center for Epidemiologic Studies Depression Scale (CES-D). Prevalence figures for depressiveness seemed to be somewhat higher in Jyvaskyla than in the two other localities. Women had more depressive symptoms than men in all three areas. The lowest mean score was recorded for Danish men and the highest level of symptoms in Finnish women. The associations discovered in this Nordic comparative study between demographic characteristics and depre…

Complex formation between the NS3 serine-type proteinase of the hepatitis C virus and NS4A and its importance for polyprotein maturation

1995

Processing of the hepatitis C virus polyprotein is mediated by host cell signalases and at least two virally encoded proteinases. Of these, the serine-type proteinase encompassing the amino-terminal one-third of NS3 is responsible for cleavage at the four sites carboxy terminal of NS3. The activity of this proteinase is modulated by NS4A, a 54-amino-acid polyprotein cleavage product essential for processing at the NS3/4A, NS4A/4B, and NS4B/5A sites and enhancing cleavage efficiency between NS5A and NS5B. Using the vaccinia virus-T7 hybrid system to express hepatitis C virus polypeptides in BHK-21 cells, we studied the role of NS4A in proteinase activation. We found that the NS3 proteinase a…

Radiochemical Studies of Complex Nuclear Reactions

1995

Quantification of ecdysteroids by immunoassay: comparison of enzyme immunoassay and radioimmunoassay.

1995

Abstract The performance of enzyme immunoassay (EIA) and radioimmunoassay (RIA) in the quantitative analysis of ecdysteroids was compared. The EIA was found to be at least equivalent to the RIA with respect to analytical range and sensitivity and to be more comfortable with respect to safety and time saving. When biological samples were analyzed by both assays a good correlation (r = 0.83) was found. Since the EIA has certain advantages over the RIA, we now recommend the use of the former assay for the quantification of ecdysteroids.

L 2-topological invariants of 3-manifolds

1995

We give results on theL2-Betti numbers and Novikov-Shubin invariants of compact manifolds, especially 3-manifolds. We first study the Betti numbers and Novikov-Shubin invariants of a chain complex of Hilbert modules over a finite von Neumann algebra. We establish inequalities among the Novikov-Shubin invariants of the terms in a short exact sequence of chain complexes. Our algebraic results, along with some analytic results on geometric 3-manifolds, are used to compute theL2-Betti numbers of compact 3-manifolds which satisfy a weak form of the geometrization conjecture, and to compute or estimate their Novikov-Shubin invariants.

Methods of controllable internal rupture in solids and liquids for obtaining atomically-clean surfaces and investigating their adhesion

1995

Controllable internal rupture (CIR) methods for obtaining atomically-clean solid surfaces and closed ultrahigh vacuum (UHV) space are described. A number of modifications of CIR methods have been developed. Their performance, characteristics and applications for investigation of adhesion are considered. CIR methods are based on the creation of virgin atomically-clean rupture surfaces in the bulk of solids during deformation of specially manufactured heterogeneous systems. For all modifications of the method, the samples have been manufactured in the form of vacuum-tight capsules and the investigation procedure has been carried out in atmospheric conditions. CIR methods, in addition to well-…

A NOTE ON THE ASYMPTOTIC PROBABILITIES OF EXISTENTIAL SECOND-ORDER MINIMAL GÖDEL SENTENCES WITH EQUALITY

1995

The minimal Gödel class is the class of first-order prenex sentences whose quantifier prefix consists of two universal quantifiers followed by just one existential quantifier. We prove that asymptotic probabilities of existential second-order sentences, whose first-order part is in the minimal Gödel class, form a dense subset of the unit interval.

Hypertension and peripheral arterial hemodynamics.

1995

Sixty uncomplicated hypertensive patients (30 stable and 30 borderline) were studied, by strain gauge plethysmography, in comparison with 25 normotensive subjects, in order to evaluate the arterial hemodynamics of the lower limbs in essential hypertension and to verify the different pattern in borderline and in stable hypertensives. Resting blood flow, even if slightly decreased in hypertensive groups, did not show significant differences in its mean values; peak flow, instead, was reduced proportionally to the severity of hypertension in all the hypertensive patients, but only in the stable hypertensives was it statistically significant. Minimal vascular resistance showed a similar behavi…