UV-Laser Plasma Study of Elemental Distributions of Paper Coatings

1995

The potential of a laser-generated plasma method in the analysis of coating coverage, coatweight distribution, and 3D distribution of various pigments of paper coating is described. A XeCl-excimer laser (308 nm) was used to generate microscopic plasma from the paper coating, and delayed detection of silicon and calcium atomic emission line intensities was used as a measure of mass vaporized. Macroscopic areas typically 10 × 10 mm2 at a spatial resolution of 250 μm were studied. With a single laser pulse (0.2 mJ of energy), about 2 ng of coating from a volume of 30 μm in diameter and 2 μm in depth was vaporized. The method seems to be useful for characterization of multilayer coatings.

Indians at Hampton Institute, 1877-1923.

1995

Naphthothiete und ihre Anwendung in der Heterocyclen-Synthese

1995

Naphtothietes and Their Application to the Synthesis of Heterocycles The three isomeric naphthothietes 5, 11, and 16 were prepared according to the reaction sequences shown in Schemes 1–3. The final step was in each case a flash vacuum pyrolysis (FVP) of the corresponding mercaptonaphthalenemethanol 4, 9, and 15, respectively. The thiete rings in 5 and 11 can be opened by gentle heating; the ring opening of the isomer 16 possesses a much higher activation barrier. A MNDO calculation of the ΔHf values of 5, 11, and 16 and the open isomers 5′, 11′, and 16′ provides an explanation for the different behavior. Photochemical ring opening represents a useful alternative. The reaction Schemes 4, 6,…

Synthesis and structural studies of 2-stannyl-substituted ferrocenylmethylamine and -phosphine derivatives 2-Me2RSnFcCH2Y (RMe, Cl; YNMe2, PPh2, P(…

1995

Abstract 2-(Trimethylstannyl)ferrocenylmethyldiphenylphosphine, 2-Me3SnFcCH2PPh2 (2a), was synthesized from 2-Me3SnFcCH2NMe2 (1a) and Ph2PH. Compound 2a is oxidized with H2O2 to 2-Me3SnFcCH2P(O)Ph2 (3a). Halogenation of 1a and 2a with Me2SnCl2 and 3a with HCl-diethyl ether yields the organotin monochlorides 2-Me3(Cl)SnFcCH2Y ( 1b , Y = NMe 2 ; 2b , Y = PPh 2 3b , Y = P ( O ) Ph 2 ) . Both crystal structure determinations and multinuclear magnetic resonance studies in solution reveal for 1b–3b molecular structures in which the tin atom approaches a trigonal bipyramidal pentacoordination as a consequence of an intramolecular Y Sn interaction. The donor strength of Y increases in the order PPh2

First evidence for the 2+ level in the very neutron-rich nucleus102Sr

1995

Evidence for the 2+ level in102Sr is obtained from theβ-decay of102Rb, mass separated at the ISOLDE facility. The energy of 126 keV and the collectivity of the 2+→0+ transition indicate that102Sr is a strongly deformed rigid rotor. In addition, a sizeable lifetime is measured for the 94 keV transition in102Y.

Counterexamples to the Kneser conjecture in dimension four.

1995

We construct a connected closed orientable smooth four-manifold whose fundamental group is the free product of two non-trivial groups such that it is not homotopy equivalent toM 0#M 1 unlessM 0 orM 1 is homeomorphic toS 4. LetN be the nucleus of the minimal elliptic Enrique surfaceV 1(2, 2) and putM=N∪ ∂NN. The fundamental group ofM splits as ℤ/2 * ℤ/2. We prove thatM#k(S 2×S2) is diffeomorphic toM 0#M 1 for non-simply connected closed smooth four-manifoldsM 0 andM 1 if and only ifk≥8. On the other hand we show thatM is homeomorphic toM 0#M 1 for closed topological four-manifoldsM 0 andM 1 withπ 1(Mi)=ℤ/2.

Chromosomal nucleolar organizer region (NOR) phenotypes in nine species of the genus Ophryotrocha (Polychaeta: Dorvilleidae)

1995

Chromosomal nucleolar organizer region (NOR) phenotypes have been characterized in nine species of the genus Ophryotrocha (Polychaeta: Dorvilleidae), namely O. notoglandulata, O. sp. macrovifera, O. sp. labronica pacifica, O. labronica labronica, O. puerilis puerilis, O. diadema, O. sp. robusta, O. gracills and O. hartmanni. Irrespective of chromosome number and morphology, Ag positive regions were terminally located in all but one species, O. diadema, where the NORs were pericentromerical in a metacentric pair. The presence of a single chromosome pair bearing NOR in invertebrates is considered an ancestral trait. According to this assumption, O. sp. robusta, O. dialema, and perhaps O. p. p…

Epithelial markers and differentiation in adnexal neoplasms of the skin: an immunohistochemical study including individual cytokeratins

1995

Applying immunohistochemical procedures for the detection of eight different cytokeratin (CK) polypeptides and other differentiation markers, we compared the staining patterns of normal cutaneous structures with those of benign adnexal tumors (n = 65). Syringomas exhibited a marker pattern highly reminiscent of that seen in normal dermal eccrine ducts (EMA in peripheral cells, CK 10 in intermediate cells, and CK 6, CK 19, and CEA in luminal cells). Nodular hidradenomas exhibited complex patterns suggesting relationship between tumor cells, including clear cells, and normal secretory coil cells (CK 7, CK 8, CK 19, and EMA); however, dermal-duct and epidermoid differentiation were also detect…

On the pathogenesis of atherosclerosis: enzymatic transformation of human low density lipoprotein to an atherogenic moiety.

1995

Combined treatment with trypsin, cholesterol esterase, and neuraminidase transforms LDL, but not HDL or VLDL, to particles with properties akin to those of lipid extracted from atherosclerotic lesions. Single or double enzyme modifications, or treatment with phospholipase C, or simple vortexing are ineffective. Triple enzyme treatment disrupts the ordered and uniform structure of LDL particles, and gives rise to the formation of inhomogeneous lipid droplets 10-200 nm in diameter with a pronounced net negative charge, but lacking significant amounts of oxidized lipid. Enzymatically modified LDL (E-LDL), but not oxidatively modified LDL (ox-LDL), is endowed with potent complement-activating c…

Pregnancy in an azoospermic patient with markedly elevated serum follicle-stimulating hormone levels

1995

Objective To assess the possibility of achieving a pregnancy in an azoospermic patient with markedly elevated serum FSH level. Design A case report. Setting In vitro fertilization program at the Instituto Valenciano de Infertilidad. Patient An azoospermic patient with small testes and serum FSH level (38.7 mlU/mL) higher than three times normal. Testicular biopsy revealed Sertoli cell-only syndrome with focal spermatogenesis. Interventions Intracytoplasmic microinjection of testicular tissue-extracted spermatozoa. Main Outcome Measurements: Fertilization rate, cleavage rate, clinical pregnancy. Results Eight of 11 (73%) intact oocytes showed two pronuclei. All of them cleaved normally. Four…

Phonons in YBa2Cu3O7?x crystals with site-selective oxygen isotope substitution: Frequencies, normal vectors, non-linear properties

1995

Lattice vibrations of YBa2Cu3O7−x crystals with a site-selective isotope substitution18O→16O are investigated theoretically. It is shown that shifts of the frequencies of A1g oxygen vibrations due to this substitution are smaller than under complete one. However, phonon bands and normal vectors are changed much stronger, especially in the case when apical oxygens are substituted. On the basis of the presented analysis anharmonic properties and transition temperatures of the selectively substituted crystals are also briefly discussed.

Host-Plant Selection and Predation Risk for Offspring of the Parent Bug

1995

Herbivores, especially specialists, must adapt to characteristics of their host to survive and reproduce successfully (Hardin and Tallamy1992). If offspring survival among different hosts varies, natural selection should lead females to choose egg-laying sites where performance of the progeny will be highest. This is especially true when newly hatched larvae cannot move to another host (Singer 1986), or when searching for new hosts would cause heavy mortality (Singer and Mandracchia 1982). A number of studies have shown that females that search for oviposition sites respond to plant characteristics that are correlated with the nutritional quality of plants for their offspring (e.g., Myers 1…

Optical properties of Cr3+ and Ni2+ ions in MgO, LiNbO3 and LMA

1995

Abstract The electronic structures of Co2+ and Ni2+ ions are obtained by the molecular orbital LCGTO-LSD method. Electrostatic matrix calculations are performed for d3 and d8 configurations. Theoretical optical data are discussed in function of the impurity site location in the crystal cell.

Measurement of the polarization of $$\Lambda ^0 , \overline \Lambda ^0 , \Sigma ^ + $$ and ?? produced in a ?? beam of 330 GeV/c

1995

The polarization of Lambda0 , AntiLambda0 , Sigma+ and Xi- inclusively produced in Sigma- induced interactions at 330 GeV has been measured in the experiment WA89 at CERN. This is the first measurement of polarization of baryons produced by a hyperon beam. No polarization of AntiLambda is observed, as was also the case in proton beam data. At transverse momenta of about 1~GeV/c Lambda0 and Sigma+ show little polarization, significantly lower than in the proton beam data, while Xi- have a polarization comparable to the polarization of Lambda0 produced in proton beams. The polarization of Lambda0, AntiLambda0, Sigma+ and Xi- inclusively produced in Sigma- induced interactions at 330 GeV has b…

Modelling of point defects in α-AL2O3

1995

Abstract The semiempirical method of the Intermediate Neglect of Differential Overlap (INDO), in the program SYMSYM, has been used for calculations on perfect and imperfect corundum crystals. For the perfect crystal the periodical Large Unit Cell (LUC) model was used while the Molecular Cluster (MC) model was used in defect calculations. By means of the MC model, we have investigated the optical properties of electronic centers (F+, F, F−, FMg, F− Mg) in corundum. Calculated optical properties of these defects are compared with experimental values and new bands are predicted to exist in the absorption spectrum of Mg-doped corundum. The energy levels of F-type and Mg-impurity related centers…

Classical growth of hard-sphere colloidal crystals.

1995

The classical theory of nucleation and growth of crystals is examined for concentrated suspensions of hard-sphere colloidal particles. The work of Russel is modified, extended, and evaluated, explicitly. Specifically, the Wilson-Frenkel growth law is modified to include the Gibbs-Thomson effect and is evaluated numerically. The results demonstrate that there is a critical nucleus radius below which crystal nuclei will not grow. A kinetic coefficient determines the maximum growth velocity possible. For large values of this coefficient, quenches to densities above the melting density show interface limited growth with the crystal radius increasing linearly with time. For quenches into the coe…

Student beliefs (or metacognitive knowledge) about SLA reconsidered

1995

In applied linguistics, interest in student beliefs (or metacognitive knowledge) about second language acquisition (SLA) is fairly recent, growing out of the emphasis on learner autonomy and on learner strategies in SLA. The purpose of this paper is to review those few studies that have been published so far, to give an outline of definitions of beliefs and research methodology, and finally to provide alternatives to these, based on recent developments in the social sciences. With a reconsideration of beliefs come reconsiderations of research data and methods.

Teaching strategies to create visual representations of key ideas in content area text materials: A longterm intervention inserted in school curricul…

1995

This paper describes a long-term research in which middle-grade school children were taught how to represent visually text key ideas through idea-mapping techniques. It consists of three studies, one for each year of our research. Children were at sixth grade when the instruction began, and they were at eighth grade when it finished. Another group of children from a different public school served as control group. Instruction was very close to the real school conditions: instructors were ordinary teachers, instruction was inserted in the content area curriculum, and ordinary textbooks were regularly employed, though combined with specially elaborated materials. Results were positive in the …

A measurement of the photon structure function F-2(gamma) at an average Q(2) of 12 GeV2/c(4)

1995

The hadronic photon structure function F_{2}^{gamma} has been measured in the Q^{2} range from 4 to 30~GeV^2/c^{4} and down to x values of order 0.001, using data taken with the DELPHI detector at LEP between 1991 and 1993. A comparison is made with several F_{2}^{gamma} parameterizations with special emphasis on their low x behaviour. A result on the Q^{2} evolution of F_{2}^{gamma} is presented.

ODEPR of indium colour centres in the X- irradiated storage phosphor KBr:In

1995

The results of measurements of the magnetic circular dichroism of the optical absorption (MCDA) and optically detected electron paramagnetic resonance (ODEPR) of X-irradiated KBr :In crystals are presented. The MCDA bands and ODEPR parameters of In°(1) centers and In 2+ centres have been measured. The mechanism of the energy storage in KBr :In crystals is found not to be simply the formation of correlated F centre-In 2+ centre pairs as was assumed previously. Considerable similarities to the storage phosphor BaFBr :Eu 2+ were found for the photostimulated emission and read-out properties.

Horizontal contraction or horizontal extension? Heterogeneous Late Eocene and early Oligocene general shearing during blueschist and greenschist faci…

1995

Mylonitic structures related to two orogenic events are described from the upper and lower contacts of the Combin zone and the immediately overlying upper Austroalpine Dent Blanche nappe/Mont Mary klippe and the directly underlying lower Austroalpine Etirol-Levaz slice. The first event, Late Eocene in age, commenced during blueschist facies P-T conditions, but pre-dated the peak of subsequent greenschist facies overprint. The second event, Early Oligocene in age, took place during retrograde greenschist facies conditions. Most sense of shear indicators associated with the retrograde mylonites indicate top SE shearing, but subordinate top NW displacing shear sense indicators have also been m…

Circular dichroism in X-ray photoemission from Pd(111) and CO/Pd(111)

1995

It is shown experimentally that in the soft X-ray region a large circular dichroism in the photoelectron angular distribution (CDAD) exists for both valence orbitals and core levels of CO molecules adsorbed on Pd(111). From theoretical consideration it follows that in the case of a spherically symmetric ground state wave function, like the 1σ and 2σ orbitals of CO, CDAD appears due to the lack of spherical symmetry in the final state. For carbonK-shell experimental results are compared to model calculations. Investigations at the Pd core levels proved that CDAD does also arise in X-ray photo-emission from non-magnetic crystals.

White-coat hypertension and cardiovascular risk

1995

OBJECTIVE: To compare cardiovascular risk in white-coat hypertensives, normotensives and established hypertensives. METHODS: We studied 61 hypertensive individuals, 27 of whom were white-coat hypertensives, and 35 normotensives. All subjects underwent 24 h noninvasive blood pressure monitoring and Doppler echocardiographic examination of the heart; urine was tested for microalbuminuria and the fundi of the eyes examined for retinopathy. RESULTS: The 24 h as well as the day- and night-time mean systolic blood pressure (SBP) was slightly but significantly higher in white-coat hypertensives than in normotensives; no significant difference was observed in diastolic blood pressure (DBP) between …

Screening individual ability to perform descriptive analysis of food products : basic statements and application to a camembert cheese descriptive pa…

1995

A battery of sensory tests is proposed to select potential descriptive panelists. This set of tests is flavor specific. Several abilities are examined: odor and taste recognition, odor memory, discrimination and descriptive capacities. A detailed example of such a battery to select a Camembert cheese descriptive panel is given. The objectives of each test are discussed. Stimuli are chosen to be consistent with the sensory properties which can be perceived in cheese. Score distributions demonstrate the discrimination among candidates for each test. Globally, results show the difficulty to find 20 panelists amongst about a hundred with good scores on each test. The panel leader has to choose …

Deep Inelastic Lepton Scattering in Nuclei at x > 1 and the Nucleon Spectral Function

1995

The nuclear structure function F_2A(x) has been studied in the Bjorken limit for (l, l') scattering on nuclei in the region of x > 1 and was found to be very sensitive to the information contained in the nucleon spectral function in nuclei, particularly the correlations between momenta and energies in the region of large momenta. Calculations were done in a local density approximation using two different spectral functions for nuclear matter. Results are compared to those obtained for a spectral function which has been evaluated directly for the finite nucleus, ^{16}O, under consideration. For values of x around 1.5 and larger the quasiparticle contribution is negligible, thus stressing …

A neutrino apparatus with improved capabilities for a short baseline νμ(νe) ↔ ντ search

1995

Abstract We propose the conceptual design of a Neutrino ApparatUS with Improved CApAbilities (NAUSICAA). This detector could be used for a new, short-baseline, high sensitivity νμ(νe) ↔ ντ oscillation search experiment at the CERN-SPS neutrino beam, as well as at the future Fermilab Main Injector neutrino beam. The heart of the detector is a finely instrumented target, made of a sandwich of a light Z material and high resolution tracking detectors. Downstream of the target there are tracking detectors for momentum measurement, followed by a compensating calorimeter. All these systems are contained within magnet providing a magnetic field of about 1 T. Following the magnet there is a muon de…

Roper excitation in alpha-proton scattering

1995

We study the Roper excitation in the $(\alpha,\alpha')$ reaction. We consider all processes which may be relevant in the Roper excitation region, namely, Roper excitation in the target, Roper excitation in the projectile, and double $\Delta$ excitation processes. The theoretical investigation shows that the Roper excitation in the proton target mediated by an isoscalar exchange is the dominant mechanism in the process. We determine an effective isoscalar interaction by means of which the experimental cross section is well reproduced. This should be useful to make predictions in related reactions and is a first step to construct eventually a microscopic $NN \rightarrow NN^*$ transition poten…

Neural and mesenchymal differentiations in Ewing's sarcoma cell lines. Morphological, immunophenotypic, molecular biological and cytogenetic evidence

1995

Three established Ewing's sarcoma (ES) cell lines (TC106, 6647, A4573), grown both in vitro and as xenograft tumors, were analyzed. In all 3 lines and tumors, the ES characteristic reciprocal translocation (11;22), as well as the presence of the ES-associated p30/32M1C2 antigen, were documented. However, these cell lines showed discrepancies in their neural and mesenchymal differentiation. The TC106 line was characterized by expression of the neuroendocrine marker secretogranin II (SgII) which was detectable by Northern blot and by radioimmunological detection (RIA) in the culture medium of secretoneurin, a proteolytic product of SgII. In contrast, TC106 cells were immunohistochemically and…

Efficient Peltier refrigeration by a pair of normal metal/ insulator/superconductor junctions

1995

We suggest and demonstrate in experiment that two normal metal /insulator/ superconductor (NIS) tunnel junctions combined in series to form a symmetric SINIS structure can operate as an efficient Peltier refrigerator. Specifically, it is shown that the SINIS structure with normal-state junction resistances 1.0 and 1.1 k$\Omega$ is capable of reaching a temperature of about 100 mK starting from 300 mK. We estimate the corresponding cooling power to be 1.5 pW per total junction area of 0.8 $\mu$m$^2$ at $T= 300$ mK.

Selectron Pair Production in e+e- Colliders and the Supergravity Spectrum

1995

Selectrons may be produced in pairs at LEPII if their mass is less than about 100 GeV. Preferably, they decay into the lightest neutralino plus an electron. In a scenario where selectrons are observed at LEPII, we show that: (i) in a first stage where experimental errors are large, the measurement of the total cross section of selectron pair production, the selectron mass, and the lightest neutralino mass, allow us to validate or rule out the Minimal Supergravity Model in its simplest form, and that (ii) in a second stage where precision measurements are available, the value of $\tan\beta$ can be determined together with the rest of the parameters that specify the Minimal Supergravity Model…

Les peines corporelles en Bourgogne au XVIIIe siècle

1995

Cohomology of Lie algebras

1995

This chapter is devoted to studying some concepts that will be extensively used in the last chapters, namely the cohomology of Lie algebras with values in a vector space, the Whitehead lemmas and Lie algebra extensions (which are related to second cohomology groups). The same three different cases of extensions of chapter 5 as well as the ℱ( M )-valued version of cohomology will be considered. In fact, the relation between Lie group and Lie algebra cohomology will be explored here, first with the simple example of central extensions of groups and algebras (governed by twococycles), and then in the higher order case, providing explicit formulae for obtaining Lie algebra cocycles from Lie gro…

Direct neutron capture for magic-shell nuclei.

1995

In neutron capture for magic--shell nuclei the direct reaction mechanism can be important and may even dominate. As an example we investigated the reaction $^{48}$Ca(n,$\gamma)^{49}$Ca for projectile energies below 250\,keV in a direct capture model using the folding procedure for optical and bound state potentials. The obtained theoretical cross sections are in agreement with the experimental data showing the dominance of the direct reaction mechanism in this case. The above method was also used to calculate the cross section for $^{50}$Ca(n,$\gamma)^{51}$Ca.

Multiple Time Scales in the Microwave Ionization of Rydberg Atoms

1995

We investigate the time dependence of the ionization probability of Rydberg atoms driven by microwave fields, both numerically and experimentally. Our exact quantum results provide evidence for an algebraic decay law on suitably chosen time scales, a phenomenon that is considered to be the signature of nonhyperbolic scattering in unbounded classically chaotic motion.

Reconstitution of bacteriorhodopsin and ATP synthase from Micrococcus luteus into liposomes of the purified main tetraether lipid from Thermoplasma a…

1995

The archaebacterium Thermoplasma acidophilum is cultivated at 59 degrees C in a medium containing sulfuric acid of pH 2. The purified bipolar membrane spanning main phospholipid (MPL) of this organism can be used to produce stable liposomes of 100-500 nm in diameter either using a French pressure cell detergent dialysis or sonication. Despite a potassium diffusion potential of 186 mV very low ionic permeability of sonicated MPL liposomes was measured using the potassium binding fluorescent indicator benzofuran isophthalate PBF1, which measures net K+ uptake. The latter also remained very low, in the presence of the K(+) ionophore valinomycin and palmitic acid. Addition of valinomycin and th…

Un modèle pour simuler l'impact d'un projet d'aménagement sur la dynamique urbaine

1995

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